lib/perl5/5.6.1/CGI.pm

   1 package CGI;
   2 require 5.004;
   3 use Carp 'croak';
   4
   5 # See the bottom of this file for the POD documentation.  Search for the
   6 # string '=head'.
   7
   8 # You can run this file through either pod2man or pod2html to produce pretty
   9 # documentation in manual or html file format (these utilities are part of the
  10 # Perl 5 distribution).
  11
  12 # Copyright 1995-1998 Lincoln D. Stein.  All rights reserved.
  13 # It may be used and modified freely, but I do request that this copyright
  14 # notice remain attached to the file.  You may modify this module as you
  15 # wish, but if you redistribute a modified version, please attach a note
  16 # listing the modifications you have made.
  17
  18 # The most recent version and complete docs are available at:
  19 #   http://stein.cshl.org/WWW/software/CGI/
  20
  21 $CGI::revision = '$Id: CGI.pm,v 1.49 2001/02/04 23:08:39 lstein Exp $';
  22 $CGI::VERSION='2.752';
  23
  24 # HARD-CODED LOCATION FOR FILE UPLOAD TEMPORARY FILES.
  25 # UNCOMMENT THIS ONLY IF YOU KNOW WHAT YOU'RE DOING.
  26 # $TempFile::TMPDIRECTORY = '/usr/tmp';
  27 use CGI::Util qw(rearrange make_attributes unescape escape expires);
  28
  29 use constant XHTML_DTD => ['-//W3C//DTD XHTML Basic 1.0//EN',
  30                            'http://www.w3.org/TR/xhtml-basic/xhtml-basic10.dtd'];
  31
  32 # >>>>> Here are some globals that you might want to adjust <<<<<<
  33 sub initialize_globals {
  34     # Set this to 1 to enable copious autoloader debugging messages
  35     $AUTOLOAD_DEBUG = 0;
  36
  37     # Set this to 1 to generate XTML-compatible output
  38     $XHTML = 1;
  39
  40     # Change this to the preferred DTD to print in start_html()
  41     # or use default_dtd('text of DTD to use');
  42     $DEFAULT_DTD = [ '-//W3C//DTD HTML 4.01 Transitional//EN',
  43                      'http://www.w3.org/TR/html4/loose.dtd' ] ;
  44
  45     # Set this to 1 to enable NOSTICKY scripts
  46     # or:
  47     #    1) use CGI qw(-nosticky)
  48     #    2) $CGI::nosticky(1)
  49     $NOSTICKY = 0;
  50
  51     # Set this to 1 to enable NPH scripts
  52     # or:
  53     #    1) use CGI qw(-nph)
  54     #    2) CGI::nph(1)
  55     #    3) print header(-nph=>1)
  56     $NPH = 0;
  57
  58     # Set this to 1 to enable debugging from @ARGV
  59     # Set to 2 to enable debugging from STDIN
  60     $DEBUG = 1;
  61
  62     # Set this to 1 to make the temporary files created
  63     # during file uploads safe from prying eyes
  64     # or do...
  65     #    1) use CGI qw(:private_tempfiles)
  66     #    2) CGI::private_tempfiles(1);
  67     $PRIVATE_TEMPFILES = 0;
  68
  69     # Set this to a positive value to limit the size of a POSTing
  70     # to a certain number of bytes:
  71     $POST_MAX = -1;
  72
  73     # Change this to 1 to disable uploads entirely:
  74     $DISABLE_UPLOADS = 0;
  75
  76     # Automatically determined -- don't change
  77     $EBCDIC = 0;
  78
  79     # Change this to 1 to suppress redundant HTTP headers
  80     $HEADERS_ONCE = 0;
  81
  82     # separate the name=value pairs by semicolons rather than ampersands
  83     $USE_PARAM_SEMICOLONS = 1;
  84
  85     # Other globals that you shouldn't worry about.
  86     undef $Q;
  87     $BEEN_THERE = 0;
  88     undef @QUERY_PARAM;
  89     undef %EXPORT;
  90     undef $QUERY_CHARSET;
  91     undef %QUERY_FIELDNAMES;
  92
  93     # prevent complaints by mod_perl
  94     1;
  95 }
  96
  97 # ------------------ START OF THE LIBRARY ------------
  98
  99 # make mod_perlhappy
 100 initialize_globals();
 101
 102 # FIGURE OUT THE OS WE'RE RUNNING UNDER
 103 # Some systems support the $^O variable.  If not
 104 # available then require() the Config library
 105 unless ($OS) {
 106     unless ($OS = $^O) {
 107         require Config;
 108         $OS = $Config::Config{'osname'};
 109     }
 110 }
 111 if ($OS =~ /^MSWin/i) {
 112   $OS = 'WINDOWS';
 113 } elsif ($OS =~ /^VMS/i) {
 114   $OS = 'VMS';
 115 } elsif ($OS =~ /^dos/i) {
 116   $OS = 'DOS';
 117 } elsif ($OS =~ /^MacOS/i) {
 118     $OS = 'MACINTOSH';
 119 } elsif ($OS =~ /^os2/i) {
 120     $OS = 'OS2';
 121 } elsif ($OS =~ /^epoc/i) {
 122     $OS = 'EPOC';
 123 } else {
 124     $OS = 'UNIX';
 125 }
 126
 127 # Some OS logic.  Binary mode enabled on DOS, NT and VMS
 128 $needs_binmode = $OS=~/^(WINDOWS|DOS|OS2|MSWin)/;
 129
 130 # This is the default class for the CGI object to use when all else fails.
 131 $DefaultClass = 'CGI' unless defined $CGI::DefaultClass;
 132
 133 # This is where to look for autoloaded routines.
 134 $AutoloadClass = $DefaultClass unless defined $CGI::AutoloadClass;
 135
 136 # The path separator is a slash, backslash or semicolon, depending
 137 # on the paltform.
 138 $SL = {
 139     UNIX=>'/', OS2=>'\\', EPOC=>'/',
 140     WINDOWS=>'\\', DOS=>'\\', MACINTOSH=>':', VMS=>'/'
 141     }->{$OS};
 142
 143 # This no longer seems to be necessary
 144 # Turn on NPH scripts by default when running under IIS server!
 145 # $NPH++ if defined($ENV{'SERVER_SOFTWARE'}) && $ENV{'SERVER_SOFTWARE'}=~/IIS/;
 146 $IIS++ if defined($ENV{'SERVER_SOFTWARE'}) && $ENV{'SERVER_SOFTWARE'}=~/IIS/;
 147
 148 # Turn on special checking for Doug MacEachern's modperl
 149 if (exists $ENV{'GATEWAY_INTERFACE'}
 150     &&
 151     ($MOD_PERL = $ENV{'GATEWAY_INTERFACE'} =~ /^CGI-Perl\//))
 152 {
 153     $| = 1;
 154     require Apache;
 155 }
 156 # Turn on special checking for ActiveState's PerlEx
 157 $PERLEX++ if defined($ENV{'GATEWAY_INTERFACE'}) && $ENV{'GATEWAY_INTERFACE'} =~ /^CGI-PerlEx/;
 158
 159 # Define the CRLF sequence.  I can't use a simple "\r\n" because the meaning
 160 # of "\n" is different on different OS's (sometimes it generates CRLF, sometimes LF
 161 # and sometimes CR).  The most popular VMS web server
 162 # doesn't accept CRLF -- instead it wants a LR.  EBCDIC machines don't
 163 # use ASCII, so \015\012 means something different.  I find this all
 164 # really annoying.
 165 $EBCDIC = "\t" ne "\011";
 166 if ($OS eq 'VMS') {
 167   $CRLF = "\n";
 168 } elsif ($EBCDIC) {
 169   $CRLF= "\r\n";
 170 } else {
 171   $CRLF = "\015\012";
 172 }
 173
 174 if ($needs_binmode) {
 175     $CGI::DefaultClass->binmode(main::STDOUT);
 176     $CGI::DefaultClass->binmode(main::STDIN);
 177     $CGI::DefaultClass->binmode(main::STDERR);
 178 }
 179
 180 %EXPORT_TAGS = (
 181                 ':html2'=>['h1'..'h6',qw/p br hr ol ul li dl dt dd menu code var strong em
 182                            tt u i b blockquote pre img a address cite samp dfn html head
 183                            base body Link nextid title meta kbd start_html end_html
 184                            input Select option comment charset escapeHTML/],
 185                 ':html3'=>[qw/div table caption th td TR Tr sup Sub strike applet Param
 186                            embed basefont style span layer ilayer font frameset frame script small big/],
 187                 ':netscape'=>[qw/blink fontsize center/],
 188                 ':form'=>[qw/textfield textarea filefield password_field hidden checkbox checkbox_group
 189                           submit reset defaults radio_group popup_menu button autoEscape
 190                           scrolling_list image_button start_form end_form startform endform
 191                           start_multipart_form end_multipart_form isindex tmpFileName uploadInfo URL_ENCODED MULTIPART/],
 192                 ':cgi'=>[qw/param upload path_info path_translated url self_url script_name cookie Dump
 193                          raw_cookie request_method query_string Accept user_agent remote_host content_type
 194                          remote_addr referer server_name server_software server_port server_protocol
 195                          virtual_host remote_ident auth_type http
 196                          save_parameters restore_parameters param_fetch
 197                          remote_user user_name header redirect import_names put
 198                          Delete Delete_all url_param cgi_error/],
 199                 ':ssl' => [qw/https/],
 200                 ':imagemap' => [qw/Area Map/],
 201                 ':cgi-lib' => [qw/ReadParse PrintHeader HtmlTop HtmlBot SplitParam Vars/],
 202                 ':html' => [qw/:html2 :html3 :netscape/],
 203                 ':standard' => [qw/:html2 :html3 :form :cgi/],
 204                 ':push' => [qw/multipart_init multipart_start multipart_end multipart_final/],
 205                 ':all' => [qw/:html2 :html3 :netscape :form :cgi :internal/]
 206                 );
 207
 208 # to import symbols into caller
 209 sub import {
 210     my $self = shift;
 211
 212 # This causes modules to clash.
 213 #    undef %EXPORT_OK;
 214 #    undef %EXPORT;
 215
 216     $self->_setup_symbols(@_);
 217     my ($callpack, $callfile, $callline) = caller;
 218
 219     # To allow overriding, search through the packages
 220     # Till we find one in which the correct subroutine is defined.
 221     my @packages = ($self,@{"$self\:\:ISA"});
 222     foreach $sym (keys %EXPORT) {
 223         my $pck;
 224         my $def = ${"$self\:\:AutoloadClass"} || $DefaultClass;
 225         foreach $pck (@packages) {
 226             if (defined(&{"$pck\:\:$sym"})) {
 227                 $def = $pck;
 228                 last;
 229             }
 230         }
 231         *{"${callpack}::$sym"} = \&{"$def\:\:$sym"};
 232     }
 233 }
 234
 235 sub compile {
 236     my $pack = shift;
 237     $pack->_setup_symbols('-compile',@_);
 238 }
 239
 240 sub expand_tags {
 241     my($tag) = @_;
 242     return ("start_$1","end_$1") if $tag=~/^(?:\*|start_|end_)(.+)/;
 243     my(@r);
 244     return ($tag) unless $EXPORT_TAGS{$tag};
 245     foreach (@{$EXPORT_TAGS{$tag}}) {
 246         push(@r,&expand_tags($_));
 247     }
 248     return @r;
 249 }
 250
 251 #### Method: new
 252 # The new routine.  This will check the current environment
 253 # for an existing query string, and initialize itself, if so.
 254 ####
 255 sub new {
 256     my($class,$initializer) = @_;
 257     my $self = {};
 258     bless $self,ref $class || $class || $DefaultClass;
 259     if ($MOD_PERL && defined Apache->request) {
 260       Apache->request->register_cleanup(\&CGI::_reset_globals);
 261       undef $NPH;
 262     }
 263     $self->_reset_globals if $PERLEX;
 264     $self->init($initializer);
 265     return $self;
 266 }
 267
 268 # We provide a DESTROY method so that the autoloader
 269 # doesn't bother trying to find it.
 270 sub DESTROY { }
 271
 272 #### Method: param
 273 # Returns the value(s)of a named parameter.
 274 # If invoked in a list context, returns the
 275 # entire list.  Otherwise returns the first
 276 # member of the list.
 277 # If name is not provided, return a list of all
 278 # the known parameters names available.
 279 # If more than one argument is provided, the
 280 # second and subsequent arguments are used to
 281 # set the value of the parameter.
 282 ####
 283 sub param {
 284     my($self,@p) = self_or_default(@_);
 285     return $self->all_parameters unless @p;
 286     my($name,$value,@other);
 287
 288     # For compatibility between old calling style and use_named_parameters() style,
 289     # we have to special case for a single parameter present.
 290     if (@p > 1) {
 291         ($name,$value,@other) = rearrange([NAME,[DEFAULT,VALUE,VALUES]],@p);
 292         my(@values);
 293
 294         if (substr($p[0],0,1) eq '-') {
 295             @values = defined($value) ? (ref($value) && ref($value) eq 'ARRAY' ? @{$value} : $value) : ();
 296         } else {
 297             foreach ($value,@other) {
 298                 push(@values,$_) if defined($_);
 299             }
 300         }
 301         # If values is provided, then we set it.
 302         if (@values) {
 303             $self->add_parameter($name);
 304             $self->{$name}=[@values];
 305         }
 306     } else {
 307         $name = $p[0];
 308     }
 309
 310     return unless defined($name) && $self->{$name};
 311     return wantarray ? @{$self->{$name}} : $self->{$name}->[0];
 312 }
 313
 314 sub self_or_default {
 315     return @_ if defined($_[0]) && (!ref($_[0])) &&($_[0] eq 'CGI');
 316     unless (defined($_[0]) &&
 317             (ref($_[0]) eq 'CGI' || UNIVERSAL::isa($_[0],'CGI')) # slightly optimized for common case
 318             ) {
 319         $Q = $CGI::DefaultClass->new unless defined($Q);
 320         unshift(@_,$Q);
 321     }
 322     return wantarray ? @_ : $Q;
 323 }
 324
 325 sub self_or_CGI {
 326     local $^W=0;                # prevent a warning
 327     if (defined($_[0]) &&
 328         (substr(ref($_[0]),0,3) eq 'CGI'
 329          || UNIVERSAL::isa($_[0],'CGI'))) {
 330         return @_;
 331     } else {
 332         return ($DefaultClass,@_);
 333     }
 334 }
 335
 336 ########################################
 337 # THESE METHODS ARE MORE OR LESS PRIVATE
 338 # GO TO THE __DATA__ SECTION TO SEE MORE
 339 # PUBLIC METHODS
 340 ########################################
 341
 342 # Initialize the query object from the environment.
 343 # If a parameter list is found, this object will be set
 344 # to an associative array in which parameter names are keys
 345 # and the values are stored as lists
 346 # If a keyword list is found, this method creates a bogus
 347 # parameter list with the single parameter 'keywords'.
 348
 349 sub init {
 350     my($self,$initializer) = @_;
 351     my($query_string,$meth,$content_length,$fh,@lines) = ('','','','');
 352     local($/) = "\n";
 353
 354     # if we get called more than once, we want to initialize
 355     # ourselves from the original query (which may be gone
 356     # if it was read from STDIN originally.)
 357     if (defined(@QUERY_PARAM) && !defined($initializer)) {
 358         foreach (@QUERY_PARAM) {
 359             $self->param('-name'=>$_,'-value'=>$QUERY_PARAM{$_});
 360         }
 361         $self->charset($QUERY_CHARSET);
 362         $self->{'.fieldnames'} = {%QUERY_FIELDNAMES};
 363         return;
 364     }
 365
 366     $meth=$ENV{'REQUEST_METHOD'} if defined($ENV{'REQUEST_METHOD'});
 367     $content_length = defined($ENV{'CONTENT_LENGTH'}) ? $ENV{'CONTENT_LENGTH'} : 0;
 368
 369     $fh = to_filehandle($initializer) if $initializer;
 370
 371     # set charset to the safe ISO-8859-1
 372     $self->charset('ISO-8859-1');
 373
 374   METHOD: {
 375
 376       # avoid unreasonably large postings
 377       if (($POST_MAX > 0) && ($content_length > $POST_MAX)) {
 378           $self->cgi_error("413 Request entity too large");
 379           last METHOD;
 380       }
 381
 382       # Process multipart postings, but only if the initializer is
 383       # not defined.
 384       if ($meth eq 'POST'
 385           && defined($ENV{'CONTENT_TYPE'})
 386           && $ENV{'CONTENT_TYPE'}=~m|^multipart/form-data|
 387           && !defined($initializer)
 388           ) {
 389           my($boundary) = $ENV{'CONTENT_TYPE'} =~ /boundary=\"?([^\";,]+)\"?/;
 390           $self->read_multipart($boundary,$content_length);
 391           last METHOD;
 392       }
 393
 394       # If initializer is defined, then read parameters
 395       # from it.
 396       if (defined($initializer)) {
 397           if (UNIVERSAL::isa($initializer,'CGI')) {
 398               $query_string = $initializer->query_string;
 399               last METHOD;
 400           }
 401           if (ref($initializer) && ref($initializer) eq 'HASH') {
 402               foreach (keys %$initializer) {
 403                   $self->param('-name'=>$_,'-value'=>$initializer->{$_});
 404               }
 405               last METHOD;
 406           }
 407
 408           if (defined($fh) && ($fh ne '')) {
 409               while (<$fh>) {
 410                   chomp;
 411                   last if /^=/;
 412                   push(@lines,$_);
 413               }
 414               # massage back into standard format
 415               if ("@lines" =~ /=/) {
 416                   $query_string=join("&",@lines);
 417               } else {
 418                   $query_string=join("+",@lines);
 419               }
 420               last METHOD;
 421           }
 422
 423           # last chance -- treat it as a string
 424           $initializer = $$initializer if ref($initializer) eq 'SCALAR';
 425           $query_string = $initializer;
 426
 427           last METHOD;
 428       }
 429
 430       # If method is GET or HEAD, fetch the query from
 431       # the environment.
 432       if ($meth=~/^(GET|HEAD)$/) {
 433           if ($MOD_PERL) {
 434               $query_string = Apache->request->args;
 435           } else {
 436               $query_string = $ENV{'QUERY_STRING'} if defined $ENV{'QUERY_STRING'};
 437               $query_string ||= $ENV{'REDIRECT_QUERY_STRING'} if defined $ENV{'REDIRECT_QUERY_STRING'};
 438           }
 439           last METHOD;
 440       }
 441
 442       if ($meth eq 'POST') {
 443           $self->read_from_client(\*STDIN,\$query_string,$content_length,0)
 444               if $content_length > 0;
 445           # Some people want to have their cake and eat it too!
 446           # Uncomment this line to have the contents of the query string
 447           # APPENDED to the POST data.
 448           # $query_string .= (length($query_string) ? '&' : '') . $ENV{'QUERY_STRING'} if defined $ENV{'QUERY_STRING'};
 449           last METHOD;
 450       }
 451
 452       # If $meth is not of GET, POST or HEAD, assume we're being debugged offline.
 453       # Check the command line and then the standard input for data.
 454       # We use the shellwords package in order to behave the way that
 455       # UN*X programmers expect.
 456       $query_string = read_from_cmdline() if $DEBUG;
 457   }
 458
 459     # We now have the query string in hand.  We do slightly
 460     # different things for keyword lists and parameter lists.
 461     if (defined $query_string && length $query_string) {
 462         if ($query_string =~ /[&=;]/) {
 463             $self->parse_params($query_string);
 464         } else {
 465             $self->add_parameter('keywords');
 466             $self->{'keywords'} = [$self->parse_keywordlist($query_string)];
 467         }
 468     }
 469
 470     # Special case.  Erase everything if there is a field named
 471     # .defaults.
 472     if ($self->param('.defaults')) {
 473         undef %{$self};
 474     }
 475
 476     # Associative array containing our defined fieldnames
 477     $self->{'.fieldnames'} = {};
 478     foreach ($self->param('.cgifields')) {
 479         $self->{'.fieldnames'}->{$_}++;
 480     }
 481
 482     # Clear out our default submission button flag if present
 483     $self->delete('.submit');
 484     $self->delete('.cgifields');
 485
 486     $self->save_request unless $initializer;
 487 }
 488
 489 # FUNCTIONS TO OVERRIDE:
 490 # Turn a string into a filehandle
 491 sub to_filehandle {
 492     my $thingy = shift;
 493     return undef unless $thingy;
 494     return $thingy if UNIVERSAL::isa($thingy,'GLOB');
 495     return $thingy if UNIVERSAL::isa($thingy,'FileHandle');
 496     if (!ref($thingy)) {
 497         my $caller = 1;
 498         while (my $package = caller($caller++)) {
 499             my($tmp) = $thingy=~/[\':]/ ? $thingy : "$package\:\:$thingy";
 500             return $tmp if defined(fileno($tmp));
 501         }
 502     }
 503     return undef;
 504 }
 505
 506 # send output to the browser
 507 sub put {
 508     my($self,@p) = self_or_default(@_);
 509     $self->print(@p);
 510 }
 511
 512 # print to standard output (for overriding in mod_perl)
 513 sub print {
 514     shift;
 515     CORE::print(@_);
 516 }
 517
 518 # get/set last cgi_error
 519 sub cgi_error {
 520     my ($self,$err) = self_or_default(@_);
 521     $self->{'.cgi_error'} = $err if defined $err;
 522     return $self->{'.cgi_error'};
 523 }
 524
 525 sub save_request {
 526     my($self) = @_;
 527     # We're going to play with the package globals now so that if we get called
 528     # again, we initialize ourselves in exactly the same way.  This allows
 529     # us to have several of these objects.
 530     @QUERY_PARAM = $self->param; # save list of parameters
 531     foreach (@QUERY_PARAM) {
 532       next unless defined $_;
 533       $QUERY_PARAM{$_}=$self->{$_};
 534     }
 535     $QUERY_CHARSET = $self->charset;
 536     %QUERY_FIELDNAMES = %{$self->{'.fieldnames'}};
 537 }
 538
 539 sub parse_params {
 540     my($self,$tosplit) = @_;
 541     my(@pairs) = split(/[&;]/,$tosplit);
 542     my($param,$value);
 543     foreach (@pairs) {
 544         ($param,$value) = split('=',$_,2);
 545         $value = '' unless defined $value;
 546         $param = unescape($param);
 547         $value = unescape($value);
 548         $self->add_parameter($param);
 549         push (@{$self->{$param}},$value);
 550     }
 551 }
 552
 553 sub add_parameter {
 554     my($self,$param)=@_;
 555     return unless defined $param;
 556     push (@{$self->{'.parameters'}},$param)
 557         unless defined($self->{$param});
 558 }
 559
 560 sub all_parameters {
 561     my $self = shift;
 562     return () unless defined($self) && $self->{'.parameters'};
 563     return () unless @{$self->{'.parameters'}};
 564     return @{$self->{'.parameters'}};
 565 }
 566
 567 # put a filehandle into binary mode (DOS)
 568 sub binmode {
 569     CORE::binmode($_[1]);
 570 }
 571
 572 sub _make_tag_func {
 573     my ($self,$tagname) = @_;
 574     my $func = qq(
 575         sub $tagname {
 576             shift if \$_[0] &&
 577                     (ref(\$_[0]) &&
 578                      (substr(ref(\$_[0]),0,3) eq 'CGI' ||
 579                     UNIVERSAL::isa(\$_[0],'CGI')));
 580             my(\$attr) = '';
 581             if (ref(\$_[0]) && ref(\$_[0]) eq 'HASH') {
 582                 my(\@attr) = make_attributes(shift()||undef,1);
 583                 \$attr = " \@attr" if \@attr;
 584             }
 585         );
 586     if ($tagname=~/start_(\w+)/i) {
 587         $func .= qq! return "<\L$1\E\$attr>";} !;
 588     } elsif ($tagname=~/end_(\w+)/i) {
 589         $func .= qq! return "<\L/$1\E>"; } !;
 590     } else {
 591         $func .= qq#
 592             return \$XHTML ? "\L<$tagname\E\$attr />" : "\L<$tagname\E\$attr>" unless \@_;
 593             my(\$tag,\$untag) = ("\L<$tagname\E\$attr>","\L</$tagname>\E");
 594             my \@result = map { "\$tag\$_\$untag" }
 595                               (ref(\$_[0]) eq 'ARRAY') ? \@{\$_[0]} : "\@_";
 596             return "\@result";
 597             }#;
 598     }
 599 return $func;
 600 }
 601
 602 sub AUTOLOAD {
 603     print STDERR "CGI::AUTOLOAD for $AUTOLOAD\n" if $CGI::AUTOLOAD_DEBUG;
 604     my $func = &_compile;
 605     goto &$func;
 606 }
 607
 608 sub _compile {
 609     my($func) = $AUTOLOAD;
 610     my($pack,$func_name);
 611     {
 612         local($1,$2); # this fixes an obscure variable suicide problem.
 613         $func=~/(.+)::([^:]+)$/;
 614         ($pack,$func_name) = ($1,$2);
 615         $pack=~s/::SUPER$//;    # fix another obscure problem
 616         $pack = ${"$pack\:\:AutoloadClass"} || $CGI::DefaultClass
 617             unless defined(${"$pack\:\:AUTOLOADED_ROUTINES"});
 618
 619         my($sub) = \%{"$pack\:\:SUBS"};
 620         unless (%$sub) {
 621            my($auto) = \${"$pack\:\:AUTOLOADED_ROUTINES"};
 622            eval "package $pack; $$auto";
 623            croak("$AUTOLOAD: $@") if $@;
 624            $$auto = '';  # Free the unneeded storage (but don't undef it!!!)
 625        }
 626        my($code) = $sub->{$func_name};
 627
 628        $code = "sub $AUTOLOAD { }" if (!$code and $func_name eq 'DESTROY');
 629        if (!$code) {
 630            (my $base = $func_name) =~ s/^(start_|end_)//i;
 631            if ($EXPORT{':any'} ||
 632                $EXPORT{'-any'} ||
 633                $EXPORT{$base} ||
 634                (%EXPORT_OK || grep(++$EXPORT_OK{$_},&expand_tags(':html')))
 635                    && $EXPORT_OK{$base}) {
 636                $code = $CGI::DefaultClass->_make_tag_func($func_name);
 637            }
 638        }
 639        croak("Undefined subroutine $AUTOLOAD\n") unless $code;
 640        eval "package $pack; $code";
 641        if ($@) {
 642            $@ =~ s/ at .*\n//;
 643            croak("$AUTOLOAD: $@");
 644        }
 645     }
 646     CORE::delete($sub->{$func_name});  #free storage
 647     return "$pack\:\:$func_name";
 648 }
 649
 650 sub _reset_globals { initialize_globals(); }
 651
 652 sub _setup_symbols {
 653     my $self = shift;
 654     my $compile = 0;
 655     foreach (@_) {
 656         $HEADERS_ONCE++,         next if /^[:-]unique_headers$/;
 657         $NPH++,                  next if /^[:-]nph$/;
 658         $NOSTICKY++,             next if /^[:-]nosticky$/;
 659         $DEBUG=0,                next if /^[:-]no_?[Dd]ebug$/;
 660         $DEBUG=2,                next if /^[:-][Dd]ebug$/;
 661         $USE_PARAM_SEMICOLONS++, next if /^[:-]newstyle_urls$/;
 662         $XHTML++,                next if /^[:-]xhtml$/;
 663         $XHTML=0,                next if /^[:-]no_?xhtml$/;
 664         $USE_PARAM_SEMICOLONS=0, next if /^[:-]oldstyle_urls$/;
 665         $PRIVATE_TEMPFILES++,    next if /^[:-]private_tempfiles$/;
 666         $EXPORT{$_}++,           next if /^[:-]any$/;
 667         $compile++,              next if /^[:-]compile$/;
 668
 669         # This is probably extremely evil code -- to be deleted some day.
 670         if (/^[-]autoload$/) {
 671             my($pkg) = caller(1);
 672             *{"${pkg}::AUTOLOAD"} = sub {
 673                 my($routine) = $AUTOLOAD;
 674                 $routine =~ s/^.*::/CGI::/;
 675                 &$routine;
 676             };
 677             next;
 678         }
 679
 680         foreach (&expand_tags($_)) {
 681             tr/a-zA-Z0-9_//cd;  # don't allow weird function names
 682             $EXPORT{$_}++;
 683         }
 684     }
 685     _compile_all(keys %EXPORT) if $compile;
 686 }
 687
 688 sub charset {
 689   my ($self,$charset) = self_or_default(@_);
 690   $self->{'.charset'} = $charset if defined $charset;
 691   $self->{'.charset'};
 692 }
 693
 694 ###############################################################################
 695 ################# THESE FUNCTIONS ARE AUTOLOADED ON DEMAND ####################
 696 ###############################################################################
 697 $AUTOLOADED_ROUTINES = '';      # get rid of -w warning
 698 $AUTOLOADED_ROUTINES=<<'END_OF_AUTOLOAD';
 699
 700 %SUBS = (
 701
 702 'URL_ENCODED'=> <<'END_OF_FUNC',
 703 sub URL_ENCODED { 'application/x-www-form-urlencoded'; }
 704 END_OF_FUNC
 705
 706 'MULTIPART' => <<'END_OF_FUNC',
 707 sub MULTIPART {  'multipart/form-data'; }
 708 END_OF_FUNC
 709
 710 'SERVER_PUSH' => <<'END_OF_FUNC',
 711 sub SERVER_PUSH { 'multipart/x-mixed-replace;boundary="' . shift() . '"'; }
 712 END_OF_FUNC
 713
 714 'new_MultipartBuffer' => <<'END_OF_FUNC',
 715 # Create a new multipart buffer
 716 sub new_MultipartBuffer {
 717     my($self,$boundary,$length,$filehandle) = @_;
 718     return MultipartBuffer->new($self,$boundary,$length,$filehandle);
 719 }
 720 END_OF_FUNC
 721
 722 'read_from_client' => <<'END_OF_FUNC',
 723 # Read data from a file handle
 724 sub read_from_client {
 725     my($self, $fh, $buff, $len, $offset) = @_;
 726     local $^W=0;                # prevent a warning
 727     return undef unless defined($fh);
 728     return read($fh, $$buff, $len, $offset);
 729 }
 730 END_OF_FUNC
 731
 732 'delete' => <<'END_OF_FUNC',
 733 #### Method: delete
 734 # Deletes the named parameter entirely.
 735 ####
 736 sub delete {
 737     my($self,@p) = self_or_default(@_);
 738     my($name) = rearrange([NAME],@p);
 739     CORE::delete $self->{$name};
 740     CORE::delete $self->{'.fieldnames'}->{$name};
 741     @{$self->{'.parameters'}}=grep($_ ne $name,$self->param());
 742     return wantarray ? () : undef;
 743 }
 744 END_OF_FUNC
 745
 746 #### Method: import_names
 747 # Import all parameters into the given namespace.
 748 # Assumes namespace 'Q' if not specified
 749 ####
 750 'import_names' => <<'END_OF_FUNC',
 751 sub import_names {
 752     my($self,$namespace,$delete) = self_or_default(@_);
 753     $namespace = 'Q' unless defined($namespace);
 754     die "Can't import names into \"main\"\n" if \%{"${namespace}::"} == \%::;
 755     if ($delete || $MOD_PERL || exists $ENV{'FCGI_ROLE'}) {
 756         # can anyone find an easier way to do this?
 757         foreach (keys %{"${namespace}::"}) {
 758             local *symbol = "${namespace}::${_}";
 759             undef $symbol;
 760             undef @symbol;
 761             undef %symbol;
 762         }
 763     }
 764     my($param,@value,$var);
 765     foreach $param ($self->param) {
 766         # protect against silly names
 767         ($var = $param)=~tr/a-zA-Z0-9_/_/c;
 768         $var =~ s/^(?=\d)/_/;
 769         local *symbol = "${namespace}::$var";
 770         @value = $self->param($param);
 771         @symbol = @value;
 772         $symbol = $value[0];
 773     }
 774 }
 775 END_OF_FUNC
 776
 777 #### Method: keywords
 778 # Keywords acts a bit differently.  Calling it in a list context
 779 # returns the list of keywords.
 780 # Calling it in a scalar context gives you the size of the list.
 781 ####
 782 'keywords' => <<'END_OF_FUNC',
 783 sub keywords {
 784     my($self,@values) = self_or_default(@_);
 785     # If values is provided, then we set it.
 786     $self->{'keywords'}=[@values] if @values;
 787     my(@result) = defined($self->{'keywords'}) ? @{$self->{'keywords'}} : ();
 788     @result;
 789 }
 790 END_OF_FUNC
 791
 792 # These are some tie() interfaces for compatibility
 793 # with Steve Brenner's cgi-lib.pl routines
 794 'Vars' => <<'END_OF_FUNC',
 795 sub Vars {
 796     my $q = shift;
 797     my %in;
 798     tie(%in,CGI,$q);
 799     return %in if wantarray;
 800     return \%in;
 801 }
 802 END_OF_FUNC
 803
 804 # These are some tie() interfaces for compatibility
 805 # with Steve Brenner's cgi-lib.pl routines
 806 'ReadParse' => <<'END_OF_FUNC',
 807 sub ReadParse {
 808     local(*in);
 809     if (@_) {
 810         *in = $_[0];
 811     } else {
 812         my $pkg = caller();
 813         *in=*{"${pkg}::in"};
 814     }
 815     tie(%in,CGI);
 816     return scalar(keys %in);
 817 }
 818 END_OF_FUNC
 819
 820 'PrintHeader' => <<'END_OF_FUNC',
 821 sub PrintHeader {
 822     my($self) = self_or_default(@_);
 823     return $self->header();
 824 }
 825 END_OF_FUNC
 826
 827 'HtmlTop' => <<'END_OF_FUNC',
 828 sub HtmlTop {
 829     my($self,@p) = self_or_default(@_);
 830     return $self->start_html(@p);
 831 }
 832 END_OF_FUNC
 833
 834 'HtmlBot' => <<'END_OF_FUNC',
 835 sub HtmlBot {
 836     my($self,@p) = self_or_default(@_);
 837     return $self->end_html(@p);
 838 }
 839 END_OF_FUNC
 840
 841 'SplitParam' => <<'END_OF_FUNC',
 842 sub SplitParam {
 843     my ($param) = @_;
 844     my (@params) = split ("\0", $param);
 845     return (wantarray ? @params : $params[0]);
 846 }
 847 END_OF_FUNC
 848
 849 'MethGet' => <<'END_OF_FUNC',
 850 sub MethGet {
 851     return request_method() eq 'GET';
 852 }
 853 END_OF_FUNC
 854
 855 'MethPost' => <<'END_OF_FUNC',
 856 sub MethPost {
 857     return request_method() eq 'POST';
 858 }
 859 END_OF_FUNC
 860
 861 'TIEHASH' => <<'END_OF_FUNC',
 862 sub TIEHASH {
 863     return $_[1] if defined $_[1];
 864     return $Q ||= new shift;
 865 }
 866 END_OF_FUNC
 867
 868 'STORE' => <<'END_OF_FUNC',
 869 sub STORE {
 870     my $self = shift;
 871     my $tag  = shift;
 872     my $vals = shift;
 873     my @vals = index($vals,"\0")!=-1 ? split("\0",$vals) : $vals;
 874     $self->param(-name=>$tag,-value=>\@vals);
 875 }
 876 END_OF_FUNC
 877
 878 'FETCH' => <<'END_OF_FUNC',
 879 sub FETCH {
 880     return $_[0] if $_[1] eq 'CGI';
 881     return undef unless defined $_[0]->param($_[1]);
 882     return join("\0",$_[0]->param($_[1]));
 883 }
 884 END_OF_FUNC
 885
 886 'FIRSTKEY' => <<'END_OF_FUNC',
 887 sub FIRSTKEY {
 888     $_[0]->{'.iterator'}=0;
 889     $_[0]->{'.parameters'}->[$_[0]->{'.iterator'}++];
 890 }
 891 END_OF_FUNC
 892
 893 'NEXTKEY' => <<'END_OF_FUNC',
 894 sub NEXTKEY {
 895     $_[0]->{'.parameters'}->[$_[0]->{'.iterator'}++];
 896 }
 897 END_OF_FUNC
 898
 899 'EXISTS' => <<'END_OF_FUNC',
 900 sub EXISTS {
 901     exists $_[0]->{$_[1]};
 902 }
 903 END_OF_FUNC
 904
 905 'DELETE' => <<'END_OF_FUNC',
 906 sub DELETE {
 907     $_[0]->delete($_[1]);
 908 }
 909 END_OF_FUNC
 910
 911 'CLEAR' => <<'END_OF_FUNC',
 912 sub CLEAR {
 913     %{$_[0]}=();
 914 }
 915 ####
 916 END_OF_FUNC
 917
 918 ####
 919 # Append a new value to an existing query
 920 ####
 921 'append' => <<'EOF',
 922 sub append {
 923     my($self,@p) = @_;
 924     my($name,$value) = rearrange([NAME,[VALUE,VALUES]],@p);
 925     my(@values) = defined($value) ? (ref($value) ? @{$value} : $value) : ();
 926     if (@values) {
 927         $self->add_parameter($name);
 928         push(@{$self->{$name}},@values);
 929     }
 930     return $self->param($name);
 931 }
 932 EOF
 933
 934 #### Method: delete_all
 935 # Delete all parameters
 936 ####
 937 'delete_all' => <<'EOF',
 938 sub delete_all {
 939     my($self) = self_or_default(@_);
 940     undef %{$self};
 941 }
 942 EOF
 943
 944 'Delete' => <<'EOF',
 945 sub Delete {
 946     my($self,@p) = self_or_default(@_);
 947     $self->delete(@p);
 948 }
 949 EOF
 950
 951 'Delete_all' => <<'EOF',
 952 sub Delete_all {
 953     my($self,@p) = self_or_default(@_);
 954     $self->delete_all(@p);
 955 }
 956 EOF
 957
 958 #### Method: autoescape
 959 # If you want to turn off the autoescaping features,
 960 # call this method with undef as the argument
 961 'autoEscape' => <<'END_OF_FUNC',
 962 sub autoEscape {
 963     my($self,$escape) = self_or_default(@_);
 964     $self->{'dontescape'}=!$escape;
 965 }
 966 END_OF_FUNC
 967
 968
 969 #### Method: version
 970 # Return the current version
 971 ####
 972 'version' => <<'END_OF_FUNC',
 973 sub version {
 974     return $VERSION;
 975 }
 976 END_OF_FUNC
 977
 978 #### Method: url_param
 979 # Return a parameter in the QUERY_STRING, regardless of
 980 # whether this was a POST or a GET
 981 ####
 982 'url_param' => <<'END_OF_FUNC',
 983 sub url_param {
 984     my ($self,@p) = self_or_default(@_);
 985     my $name = shift(@p);
 986     return undef unless exists($ENV{QUERY_STRING});
 987     unless (exists($self->{'.url_param'})) {
 988         $self->{'.url_param'}={}; # empty hash
 989         if ($ENV{QUERY_STRING} =~ /=/) {
 990             my(@pairs) = split(/[&;]/,$ENV{QUERY_STRING});
 991             my($param,$value);
 992             foreach (@pairs) {
 993                 ($param,$value) = split('=',$_,2);
 994                 $param = unescape($param);
 995                 $value = unescape($value);
 996                 push(@{$self->{'.url_param'}->{$param}},$value);
 997             }
 998         } else {
 999             $self->{'.url_param'}->{'keywords'} = [$self->parse_keywordlist($ENV{QUERY_STRING})];
1000         }
1001     }
1002     return keys %{$self->{'.url_param'}} unless defined($name);
1003     return () unless $self->{'.url_param'}->{$name};
1004     return wantarray ? @{$self->{'.url_param'}->{$name}}
1005                      : $self->{'.url_param'}->{$name}->[0];
1006 }
1007 END_OF_FUNC
1008
1009 #### Method: Dump
1010 # Returns a string in which all the known parameter/value
1011 # pairs are represented as nested lists, mainly for the purposes
1012 # of debugging.
1013 ####
1014 'Dump' => <<'END_OF_FUNC',
1015 sub Dump {
1016     my($self) = self_or_default(@_);
1017     my($param,$value,@result);
1018     return '<UL></UL>' unless $self->param;
1019     push(@result,"<UL>");
1020     foreach $param ($self->param) {
1021         my($name)=$self->escapeHTML($param);
1022         push(@result,"<LI><STRONG>$param</STRONG>");
1023         push(@result,"<UL>");
1024         foreach $value ($self->param($param)) {
1025             $value = $self->escapeHTML($value);
1026             $value =~ s/\n/<BR>\n/g;
1027             push(@result,"<LI>$value");
1028         }
1029         push(@result,"</UL>");
1030     }
1031     push(@result,"</UL>\n");
1032     return join("\n",@result);
1033 }
1034 END_OF_FUNC
1035
1036 #### Method as_string
1037 #
1038 # synonym for "dump"
1039 ####
1040 'as_string' => <<'END_OF_FUNC',
1041 sub as_string {
1042     &Dump(@_);
1043 }
1044 END_OF_FUNC
1045
1046 #### Method: save
1047 # Write values out to a filehandle in such a way that they can
1048 # be reinitialized by the filehandle form of the new() method
1049 ####
1050 'save' => <<'END_OF_FUNC',
1051 sub save {
1052     my($self,$filehandle) = self_or_default(@_);
1053     $filehandle = to_filehandle($filehandle);
1054     my($param);
1055     local($,) = '';  # set print field separator back to a sane value
1056     local($\) = '';  # set output line separator to a sane value
1057     foreach $param ($self->param) {
1058         my($escaped_param) = escape($param);
1059         my($value);
1060         foreach $value ($self->param($param)) {
1061             print $filehandle "$escaped_param=",escape("$value"),"\n";
1062         }
1063     }
1064     foreach (keys %{$self->{'.fieldnames'}}) {
1065           print $filehandle ".cgifields=",escape("$_"),"\n";
1066     }
1067     print $filehandle "=\n";    # end of record
1068 }
1069 END_OF_FUNC
1070
1071
1072 #### Method: save_parameters
1073 # An alias for save() that is a better name for exportation.
1074 # Only intended to be used with the function (non-OO) interface.
1075 ####
1076 'save_parameters' => <<'END_OF_FUNC',
1077 sub save_parameters {
1078     my $fh = shift;
1079     return save(to_filehandle($fh));
1080 }
1081 END_OF_FUNC
1082
1083 #### Method: restore_parameters
1084 # A way to restore CGI parameters from an initializer.
1085 # Only intended to be used with the function (non-OO) interface.
1086 ####
1087 'restore_parameters' => <<'END_OF_FUNC',
1088 sub restore_parameters {
1089     $Q = $CGI::DefaultClass->new(@_);
1090 }
1091 END_OF_FUNC
1092
1093 #### Method: multipart_init
1094 # Return a Content-Type: style header for server-push
1095 # This has to be NPH on most web servers, and it is advisable to set $| = 1
1096 #
1097 # Many thanks to Ed Jordan <ed@fidalgo.net> for this
1098 # contribution, updated by Andrew Benham (adsb@bigfoot.com)
1099 ####
1100 'multipart_init' => <<'END_OF_FUNC',
1101 sub multipart_init {
1102     my($self,@p) = self_or_default(@_);
1103     my($boundary,@other) = rearrange([BOUNDARY],@p);
1104     $boundary = $boundary || '------- =_aaaaaaaaaa0';
1105     $self->{'separator'} = "$CRLF--$boundary$CRLF";
1106     $self->{'final_separator'} = "$CRLF--$boundary--$CRLF";
1107     $type = SERVER_PUSH($boundary);
1108     return $self->header(
1109         -nph => 1,
1110         -type => $type,
1111         (map { split "=", $_, 2 } @other),
1112     ) . "WARNING: YOUR BROWSER DOESN'T SUPPORT THIS SERVER-PUSH TECHNOLOGY." . $self->multipart_end;
1113 }
1114 END_OF_FUNC
1115
1116
1117 #### Method: multipart_start
1118 # Return a Content-Type: style header for server-push, start of section
1119 #
1120 # Many thanks to Ed Jordan <ed@fidalgo.net> for this
1121 # contribution, updated by Andrew Benham (adsb@bigfoot.com)
1122 ####
1123 'multipart_start' => <<'END_OF_FUNC',
1124 sub multipart_start {
1125     my(@header);
1126     my($self,@p) = self_or_default(@_);
1127     my($type,@other) = rearrange([TYPE],@p);
1128     $type = $type || 'text/html';
1129     push(@header,"Content-Type: $type");
1130
1131     # rearrange() was designed for the HTML portion, so we
1132     # need to fix it up a little.
1133     foreach (@other) {
1134         next unless my($header,$value) = /([^\s=]+)=\"?(.+?)\"?$/;
1135         ($_ = $header) =~ s/^(\w)(.*)/$1 . lc ($2) . ': '.$self->unescapeHTML($value)/e;
1136     }
1137     push(@header,@other);
1138     my $header = join($CRLF,@header)."${CRLF}${CRLF}";
1139     return $header;
1140 }
1141 END_OF_FUNC
1142
1143
1144 #### Method: multipart_end
1145 # Return a MIME boundary separator for server-push, end of section
1146 #
1147 # Many thanks to Ed Jordan <ed@fidalgo.net> for this
1148 # contribution
1149 ####
1150 'multipart_end' => <<'END_OF_FUNC',
1151 sub multipart_end {
1152     my($self,@p) = self_or_default(@_);
1153     return $self->{'separator'};
1154 }
1155 END_OF_FUNC
1156
1157
1158 #### Method: multipart_final
1159 # Return a MIME boundary separator for server-push, end of all sections
1160 #
1161 # Contributed by Andrew Benham (adsb@bigfoot.com)
1162 ####
1163 'multipart_final' => <<'END_OF_FUNC',
1164 sub multipart_final {
1165     my($self,@p) = self_or_default(@_);
1166     return $self->{'final_separator'} . "WARNING: YOUR BROWSER DOESN'T SUPPORT THIS SERVER-PUSH TECHNOLOGY." . $CRLF;
1167 }
1168 END_OF_FUNC
1169
1170
1171 #### Method: header
1172 # Return a Content-Type: style header
1173 #
1174 ####
1175 'header' => <<'END_OF_FUNC',
1176 sub header {
1177     my($self,@p) = self_or_default(@_);
1178     my(@header);
1179
1180     return undef if $self->{'.header_printed'}++ and $HEADERS_ONCE;
1181
1182     my($type,$status,$cookie,$target,$expires,$nph,$charset,$attachment,@other) =
1183         rearrange([['TYPE','CONTENT_TYPE','CONTENT-TYPE'],
1184                             'STATUS',['COOKIE','COOKIES'],'TARGET',
1185                             'EXPIRES','NPH','CHARSET',
1186                             'ATTACHMENT'],@p);
1187
1188     $nph     ||= $NPH;
1189     if (defined $charset) {
1190       $self->charset($charset);
1191     } else {
1192       $charset = $self->charset;
1193     }
1194
1195     # rearrange() was designed for the HTML portion, so we
1196     # need to fix it up a little.
1197     foreach (@other) {
1198         next unless my($header,$value) = /([^\s=]+)=\"?(.+?)\"?$/;
1199         ($_ = $header) =~ s/^(\w)(.*)/$1 . lc ($2) . ': '.$self->unescapeHTML($value)/e;
1200     }
1201
1202     $type ||= 'text/html' unless defined($type);
1203     $type .= "; charset=$charset" if $type ne '' and $type =~ m!^text/! and $type !~ /\bcharset\b/;
1204
1205     # Maybe future compatibility.  Maybe not.
1206     my $protocol = $ENV{SERVER_PROTOCOL} || 'HTTP/1.0';
1207     push(@header,$protocol . ' ' . ($status || '200 OK')) if $nph;
1208     push(@header,"Server: " . &server_software()) if $nph;
1209
1210     push(@header,"Status: $status") if $status;
1211     push(@header,"Window-Target: $target") if $target;
1212     # push all the cookies -- there may be several
1213     if ($cookie) {
1214         my(@cookie) = ref($cookie) && ref($cookie) eq 'ARRAY' ? @{$cookie} : $cookie;
1215         foreach (@cookie) {
1216             my $cs = UNIVERSAL::isa($_,'CGI::Cookie') ? $_->as_string : $_;
1217             push(@header,"Set-Cookie: $cs") if $cs ne '';
1218         }
1219     }
1220     # if the user indicates an expiration time, then we need
1221     # both an Expires and a Date header (so that the browser is
1222     # uses OUR clock)
1223     push(@header,"Expires: " . expires($expires,'http'))
1224         if $expires;
1225     push(@header,"Date: " . expires(0,'http')) if $expires || $cookie || $nph;
1226     push(@header,"Pragma: no-cache") if $self->cache();
1227     push(@header,"Content-Disposition: attachment; filename=\"$attachment\"") if $attachment;
1228     push(@header,@other);
1229     push(@header,"Content-Type: $type") if $type ne '';
1230
1231     my $header = join($CRLF,@header)."${CRLF}${CRLF}";
1232     if ($MOD_PERL and not $nph) {
1233         my $r = Apache->request;
1234         $r->send_cgi_header($header);
1235         return '';
1236     }
1237     return $header;
1238 }
1239 END_OF_FUNC
1240
1241
1242 #### Method: cache
1243 # Control whether header() will produce the no-cache
1244 # Pragma directive.
1245 ####
1246 'cache' => <<'END_OF_FUNC',
1247 sub cache {
1248     my($self,$new_value) = self_or_default(@_);
1249     $new_value = '' unless $new_value;
1250     if ($new_value ne '') {
1251         $self->{'cache'} = $new_value;
1252     }
1253     return $self->{'cache'};
1254 }
1255 END_OF_FUNC
1256
1257
1258 #### Method: redirect
1259 # Return a Location: style header
1260 #
1261 ####
1262 'redirect' => <<'END_OF_FUNC',
1263 sub redirect {
1264     my($self,@p) = self_or_default(@_);
1265     my($url,$target,$cookie,$nph,@other) = rearrange([[LOCATION,URI,URL],TARGET,COOKIE,NPH],@p);
1266     $url ||= $self->self_url;
1267     my(@o);
1268     foreach (@other) { tr/\"//d; push(@o,split("=",$_,2)); }
1269     unshift(@o,
1270          '-Status'=>'302 Moved',
1271          '-Location'=>$url,
1272          '-nph'=>$nph);
1273     unshift(@o,'-Target'=>$target) if $target;
1274     unshift(@o,'-Cookie'=>$cookie) if $cookie;
1275     unshift(@o,'-Type'=>'');
1276     return $self->header(@o);
1277 }
1278 END_OF_FUNC
1279
1280
1281 #### Method: start_html
1282 # Canned HTML header
1283 #
1284 # Parameters:
1285 # $title -> (optional) The title for this HTML document (-title)
1286 # $author -> (optional) e-mail address of the author (-author)
1287 # $base -> (optional) if set to true, will enter the BASE address of this document
1288 #          for resolving relative references (-base)
1289 # $xbase -> (optional) alternative base at some remote location (-xbase)
1290 # $target -> (optional) target window to load all links into (-target)
1291 # $script -> (option) Javascript code (-script)
1292 # $no_script -> (option) Javascript <noscript> tag (-noscript)
1293 # $meta -> (optional) Meta information tags
1294 # $head -> (optional) any other elements you'd like to incorporate into the <HEAD> tag
1295 #           (a scalar or array ref)
1296 # $style -> (optional) reference to an external style sheet
1297 # @other -> (optional) any other named parameters you'd like to incorporate into
1298 #           the <BODY> tag.
1299 ####
1300 'start_html' => <<'END_OF_FUNC',
1301 sub start_html {
1302     my($self,@p) = &self_or_default(@_);
1303     my($title,$author,$base,$xbase,$script,$noscript,$target,$meta,$head,$style,$dtd,$lang,@other) =
1304         rearrange([TITLE,AUTHOR,BASE,XBASE,SCRIPT,NOSCRIPT,TARGET,META,HEAD,STYLE,DTD,LANG],@p);
1305
1306     # strangely enough, the title needs to be escaped as HTML
1307     # while the author needs to be escaped as a URL
1308     $title = $self->escapeHTML($title || 'Untitled Document');
1309     $author = $self->escape($author);
1310     $lang ||= 'en-US';
1311     my(@result,$xml_dtd);
1312     if ($dtd) {
1313         if (defined(ref($dtd)) and (ref($dtd) eq 'ARRAY')) {
1314             $dtd = $DEFAULT_DTD unless $dtd->[0] =~ m|^-//|;
1315         } else {
1316             $dtd = $DEFAULT_DTD unless $dtd =~ m|^-//|;
1317         }
1318     } else {
1319         $dtd = $XHTML ? XHTML_DTD : $DEFAULT_DTD;
1320     }
1321
1322     $xml_dtd++ if ref($dtd) eq 'ARRAY' && $dtd->[0] =~ /\bXHTML\b/i;
1323     $xml_dtd++ if ref($dtd) eq '' && $dtd =~ /\bXHTML\b/i;
1324     push @result,q(<?xml version="1.0" encoding="utf-8"?>) if $xml_dtd;
1325
1326     if (ref($dtd) && ref($dtd) eq 'ARRAY') {
1327         push(@result,qq(<!DOCTYPE html\n\tPUBLIC "$dtd->[0]"\n\t"$dtd->[1]">));
1328     } else {
1329         push(@result,qq(<!DOCTYPE html\n\tPUBLIC "$dtd">));
1330     }
1331     push(@result,$XHTML ? qq(<html xmlns="http://www.w3.org/1999/xhtml" lang="$lang"><head><title>$title</title>)
1332                         : qq(<html lang="$lang"><head><title>$title</title>));
1333         if (defined $author) {
1334     push(@result,$XHTML ? "<link rev=\"made\" href=\"mailto:$author\" />"
1335                                                                 : "<link rev=\"made\" href=\"mailto:$author\">");
1336         }
1337
1338     if ($base || $xbase || $target) {
1339         my $href = $xbase || $self->url('-path'=>1);
1340         my $t = $target ? qq/ target="$target"/ : '';
1341         push(@result,$XHTML ? qq(<base href="$href"$t />) : qq(<base href="$href"$t>));
1342     }
1343
1344     if ($meta && ref($meta) && (ref($meta) eq 'HASH')) {
1345         foreach (keys %$meta) { push(@result,$XHTML ? qq(<meta name="$_" content="$meta->{$_}" />)
1346                         : qq(<meta name="$_" content="$meta->{$_}">)); }
1347     }
1348
1349     push(@result,ref($head) ? @$head : $head) if $head;
1350
1351     # handle the infrequently-used -style and -script parameters
1352     push(@result,$self->_style($style)) if defined $style;
1353     push(@result,$self->_script($script)) if defined $script;
1354
1355     # handle -noscript parameter
1356     push(@result,<<END) if $noscript;
1357 <noscript>
1358 $noscript
1359 </noscript>
1360 END
1361     ;
1362     my($other) = @other ? " @other" : '';
1363     push(@result,"</head><body$other>");
1364     return join("\n",@result);
1365 }
1366 END_OF_FUNC
1367
1368 ### Method: _style
1369 # internal method for generating a CSS style section
1370 ####
1371 '_style' => <<'END_OF_FUNC',
1372 sub _style {
1373     my ($self,$style) = @_;
1374     my (@result);
1375     my $type = 'text/css';
1376
1377     my $cdata_start = $XHTML ? "\n<!--/* <![CDATA[ */" : "\n<!-- ";
1378     my $cdata_end   = $XHTML ? "\n/* ]]> */-->\n" : " -->\n";
1379
1380     if (ref($style)) {
1381      my($src,$code,$stype,@other) =
1382          rearrange([SRC,CODE,TYPE],
1383                     '-foo'=>'bar', # a trick to allow the '-' to be omitted
1384                     ref($style) eq 'ARRAY' ? @$style : %$style);
1385      $type = $stype if $stype;
1386      if (ref($src) eq "ARRAY") # Check to see if the $src variable is an array reference
1387      { # If it is, push a LINK tag for each one.
1388        foreach $src (@$src)
1389        {
1390          push(@result,$XHTML ? qq(<link rel="stylesheet" type="$type" href="$src" />)
1391                              : qq(<link rel="stylesheet" type="$type" href="$src">/)) if $src;
1392        }
1393      }
1394      else
1395      { # Otherwise, push the single -src, if it exists.
1396        push(@result,$XHTML ? qq(<link rel="stylesheet" type="$type" href="$src" />)
1397                            : qq(<link rel="stylesheet" type="$type" href="$src">)
1398             ) if $src;
1399       }
1400      push(@result,style({'type'=>$type},"$cdata_start\n$code\n$cdata_end")) if $code;
1401     } else {
1402      push(@result,style({'type'=>$type},"$cdata_start\n$style\n$cdata_end"));
1403     }
1404     @result;
1405 }
1406 END_OF_FUNC
1407
1408 '_script' => <<'END_OF_FUNC',
1409 sub _script {
1410     my ($self,$script) = @_;
1411     my (@result);
1412
1413     my (@scripts) = ref($script) eq 'ARRAY' ? @$script : ($script);
1414     foreach $script (@scripts) {
1415         my($src,$code,$language);
1416         if (ref($script)) { # script is a hash
1417             ($src,$code,$language, $type) =
1418                 rearrange([SRC,CODE,LANGUAGE,TYPE],
1419                                  '-foo'=>'bar', # a trick to allow the '-' to be omitted
1420                                  ref($script) eq 'ARRAY' ? @$script : %$script);
1421             # User may not have specified language
1422             $language ||= 'JavaScript';
1423             unless (defined $type) {
1424                 $type = lc $language;
1425                 # strip '1.2' from 'javascript1.2'
1426                 $type =~ s/^(\D+).*$/text\/$1/;
1427             }
1428         } else {
1429             ($src,$code,$language, $type) = ('',$script,'JavaScript', 'text/javascript');
1430         }
1431
1432     my $comment = '//';  # javascript by default
1433     $comment = '#' if $type=~/perl|tcl/i;
1434     $comment = "'" if $type=~/vbscript/i;
1435
1436     my $cdata_start  =  "\n<!-- Hide script\n";
1437     $cdata_start    .= "$comment<![CDATA[\n"  if $XHTML;
1438     my $cdata_end    = $XHTML ? "\n$comment]]>" : $comment;
1439     $cdata_end      .= " End script hiding -->\n";
1440
1441         my(@satts);
1442         push(@satts,'src'=>$src) if $src;
1443         push(@satts,'language'=>$language);
1444         push(@satts,'type'=>$type);
1445         $code = "$cdata_start$code$cdata_end" if defined $code;
1446         push(@result,script({@satts},$code || ''));
1447     }
1448     @result;
1449 }
1450 END_OF_FUNC
1451
1452 #### Method: end_html
1453 # End an HTML document.
1454 # Trivial method for completeness.  Just returns "</BODY>"
1455 ####
1456 'end_html' => <<'END_OF_FUNC',
1457 sub end_html {
1458     return "</body></html>";
1459 }
1460 END_OF_FUNC
1461
1462
1463 ################################
1464 # METHODS USED IN BUILDING FORMS
1465 ################################
1466
1467 #### Method: isindex
1468 # Just prints out the isindex tag.
1469 # Parameters:
1470 #  $action -> optional URL of script to run
1471 # Returns:
1472 #   A string containing a <ISINDEX> tag
1473 'isindex' => <<'END_OF_FUNC',
1474 sub isindex {
1475     my($self,@p) = self_or_default(@_);
1476     my($action,@other) = rearrange([ACTION],@p);
1477     $action = qq/action="$action"/ if $action;
1478     my($other) = @other ? " @other" : '';
1479     return $XHTML ? "<isindex $action$other />" : "<isindex $action$other>";
1480 }
1481 END_OF_FUNC
1482
1483
1484 #### Method: startform
1485 # Start a form
1486 # Parameters:
1487 #   $method -> optional submission method to use (GET or POST)
1488 #   $action -> optional URL of script to run
1489 #   $enctype ->encoding to use (URL_ENCODED or MULTIPART)
1490 'startform' => <<'END_OF_FUNC',
1491 sub startform {
1492     my($self,@p) = self_or_default(@_);
1493
1494     my($method,$action,$enctype,@other) =
1495         rearrange([METHOD,ACTION,ENCTYPE],@p);
1496
1497     $method = lc($method) || 'post';
1498     $enctype = $enctype || &URL_ENCODED;
1499     unless (defined $action) {
1500        $action = $self->url(-absolute=>1,-path=>1);
1501        $action .= "?$ENV{QUERY_STRING}" if $ENV{QUERY_STRING};
1502     }
1503     $action = qq(action="$action");
1504     my($other) = @other ? " @other" : '';
1505     $self->{'.parametersToAdd'}={};
1506     return qq/<form method="$method" $action enctype="$enctype"$other>\n/;
1507 }
1508 END_OF_FUNC
1509
1510
1511 #### Method: start_form
1512 # synonym for startform
1513 'start_form' => <<'END_OF_FUNC',
1514 sub start_form {
1515     &startform;
1516 }
1517 END_OF_FUNC
1518
1519 'end_multipart_form' => <<'END_OF_FUNC',
1520 sub end_multipart_form {
1521     &endform;
1522 }
1523 END_OF_FUNC
1524
1525 #### Method: start_multipart_form
1526 # synonym for startform
1527 'start_multipart_form' => <<'END_OF_FUNC',
1528 sub start_multipart_form {
1529     my($self,@p) = self_or_default(@_);
1530     if (defined($param[0]) && substr($param[0],0,1) eq '-') {
1531         my(%p) = @p;
1532         $p{'-enctype'}=&MULTIPART;
1533         return $self->startform(%p);
1534     } else {
1535         my($method,$action,@other) =
1536             rearrange([METHOD,ACTION],@p);
1537         return $self->startform($method,$action,&MULTIPART,@other);
1538     }
1539 }
1540 END_OF_FUNC
1541
1542
1543 #### Method: endform
1544 # End a form
1545 'endform' => <<'END_OF_FUNC',
1546 sub endform {
1547     my($self,@p) = self_or_default(@_);
1548     if ( $NOSTICKY ) {
1549     return wantarray ? ("</form>") : "\n</form>";
1550     } else {
1551     return wantarray ? ($self->get_fields,"</form>") :
1552                         $self->get_fields ."\n</form>";
1553     }
1554 }
1555 END_OF_FUNC
1556
1557
1558 #### Method: end_form
1559 # synonym for endform
1560 'end_form' => <<'END_OF_FUNC',
1561 sub end_form {
1562     &endform;
1563 }
1564 END_OF_FUNC
1565
1566
1567 '_textfield' => <<'END_OF_FUNC',
1568 sub _textfield {
1569     my($self,$tag,@p) = self_or_default(@_);
1570     my($name,$default,$size,$maxlength,$override,@other) =
1571         rearrange([NAME,[DEFAULT,VALUE],SIZE,MAXLENGTH,[OVERRIDE,FORCE]],@p);
1572
1573     my $current = $override ? $default :
1574         (defined($self->param($name)) ? $self->param($name) : $default);
1575
1576     $current = defined($current) ? $self->escapeHTML($current,1) : '';
1577     $name = defined($name) ? $self->escapeHTML($name) : '';
1578     my($s) = defined($size) ? qq/ size="$size"/ : '';
1579     my($m) = defined($maxlength) ? qq/ maxlength="$maxlength"/ : '';
1580     my($other) = @other ? " @other" : '';
1581     # this entered at cristy's request to fix problems with file upload fields
1582     # and WebTV -- not sure it won't break stuff
1583     my($value) = $current ne '' ? qq(value="$current") : '';
1584     return $XHTML ? qq(<input type="$tag" name="$name" $value$s$m$other />)
1585                   : qq/<input type="$tag" name="$name" $value$s$m$other>/;
1586 }
1587 END_OF_FUNC
1588
1589 #### Method: textfield
1590 # Parameters:
1591 #   $name -> Name of the text field
1592 #   $default -> Optional default value of the field if not
1593 #                already defined.
1594 #   $size ->  Optional width of field in characaters.
1595 #   $maxlength -> Optional maximum number of characters.
1596 # Returns:
1597 #   A string containing a <INPUT TYPE="text"> field
1598 #
1599 'textfield' => <<'END_OF_FUNC',
1600 sub textfield {
1601     my($self,@p) = self_or_default(@_);
1602     $self->_textfield('text',@p);
1603 }
1604 END_OF_FUNC
1605
1606
1607 #### Method: filefield
1608 # Parameters:
1609 #   $name -> Name of the file upload field
1610 #   $size ->  Optional width of field in characaters.
1611 #   $maxlength -> Optional maximum number of characters.
1612 # Returns:
1613 #   A string containing a <INPUT TYPE="text"> field
1614 #
1615 'filefield' => <<'END_OF_FUNC',
1616 sub filefield {
1617     my($self,@p) = self_or_default(@_);
1618     $self->_textfield('file',@p);
1619 }
1620 END_OF_FUNC
1621
1622
1623 #### Method: password
1624 # Create a "secret password" entry field
1625 # Parameters:
1626 #   $name -> Name of the field
1627 #   $default -> Optional default value of the field if not
1628 #                already defined.
1629 #   $size ->  Optional width of field in characters.
1630 #   $maxlength -> Optional maximum characters that can be entered.
1631 # Returns:
1632 #   A string containing a <INPUT TYPE="password"> field
1633 #
1634 'password_field' => <<'END_OF_FUNC',
1635 sub password_field {
1636     my ($self,@p) = self_or_default(@_);
1637     $self->_textfield('password',@p);
1638 }
1639 END_OF_FUNC
1640
1641 #### Method: textarea
1642 # Parameters:
1643 #   $name -> Name of the text field
1644 #   $default -> Optional default value of the field if not
1645 #                already defined.
1646 #   $rows ->  Optional number of rows in text area
1647 #   $columns -> Optional number of columns in text area
1648 # Returns:
1649 #   A string containing a <TEXTAREA></TEXTAREA> tag
1650 #
1651 'textarea' => <<'END_OF_FUNC',
1652 sub textarea {
1653     my($self,@p) = self_or_default(@_);
1654
1655     my($name,$default,$rows,$cols,$override,@other) =
1656         rearrange([NAME,[DEFAULT,VALUE],ROWS,[COLS,COLUMNS],[OVERRIDE,FORCE]],@p);
1657
1658     my($current)= $override ? $default :
1659         (defined($self->param($name)) ? $self->param($name) : $default);
1660
1661     $name = defined($name) ? $self->escapeHTML($name) : '';
1662     $current = defined($current) ? $self->escapeHTML($current) : '';
1663     my($r) = $rows ? " rows=$rows" : '';
1664     my($c) = $cols ? " cols=$cols" : '';
1665     my($other) = @other ? " @other" : '';
1666     return qq{<textarea name="$name"$r$c$other>$current</textarea>};
1667 }
1668 END_OF_FUNC
1669
1670
1671 #### Method: button
1672 # Create a javascript button.
1673 # Parameters:
1674 #   $name ->  (optional) Name for the button. (-name)
1675 #   $value -> (optional) Value of the button when selected (and visible name) (-value)
1676 #   $onclick -> (optional) Text of the JavaScript to run when the button is
1677 #                clicked.
1678 # Returns:
1679 #   A string containing a <INPUT TYPE="button"> tag
1680 ####
1681 'button' => <<'END_OF_FUNC',
1682 sub button {
1683     my($self,@p) = self_or_default(@_);
1684
1685     my($label,$value,$script,@other) = rearrange([NAME,[VALUE,LABEL],
1686                                                          [ONCLICK,SCRIPT]],@p);
1687
1688     $label=$self->escapeHTML($label);
1689     $value=$self->escapeHTML($value,1);
1690     $script=$self->escapeHTML($script);
1691
1692     my($name) = '';
1693     $name = qq/ name="$label"/ if $label;
1694     $value = $value || $label;
1695     my($val) = '';
1696     $val = qq/ value="$value"/ if $value;
1697     $script = qq/ onclick="$script"/ if $script;
1698     my($other) = @other ? " @other" : '';
1699     return $XHTML ? qq(<input type="button"$name$val$script$other />)
1700                   : qq/<input type="button"$name$val$script$other>/;
1701 }
1702 END_OF_FUNC
1703
1704
1705 #### Method: submit
1706 # Create a "submit query" button.
1707 # Parameters:
1708 #   $name ->  (optional) Name for the button.
1709 #   $value -> (optional) Value of the button when selected (also doubles as label).
1710 #   $label -> (optional) Label printed on the button(also doubles as the value).
1711 # Returns:
1712 #   A string containing a <INPUT TYPE="submit"> tag
1713 ####
1714 'submit' => <<'END_OF_FUNC',
1715 sub submit {
1716     my($self,@p) = self_or_default(@_);
1717
1718     my($label,$value,@other) = rearrange([NAME,[VALUE,LABEL]],@p);
1719
1720     $label=$self->escapeHTML($label);
1721     $value=$self->escapeHTML($value,1);
1722
1723     my($name) = ' name=".submit"' unless $NOSTICKY;
1724     $name = qq/ name="$label"/ if defined($label);
1725     $value = defined($value) ? $value : $label;
1726     my($val) = '';
1727     $val = qq/ value="$value"/ if defined($value);
1728     my($other) = @other ? " @other" : '';
1729     return $XHTML ? qq(<input type="submit"$name$val$other />)
1730                   : qq/<input type="submit"$name$val$other>/;
1731 }
1732 END_OF_FUNC
1733
1734
1735 #### Method: reset
1736 # Create a "reset" button.
1737 # Parameters:
1738 #   $name -> (optional) Name for the button.
1739 # Returns:
1740 #   A string containing a <INPUT TYPE="reset"> tag
1741 ####
1742 'reset' => <<'END_OF_FUNC',
1743 sub reset {
1744     my($self,@p) = self_or_default(@_);
1745     my($label,@other) = rearrange([NAME],@p);
1746     $label=$self->escapeHTML($label);
1747     my($value) = defined($label) ? qq/ value="$label"/ : '';
1748     my($other) = @other ? " @other" : '';
1749     return $XHTML ? qq(<input type="reset"$value$other />)
1750                   : qq/<input type="reset"$value$other>/;
1751 }
1752 END_OF_FUNC
1753
1754
1755 #### Method: defaults
1756 # Create a "defaults" button.
1757 # Parameters:
1758 #   $name -> (optional) Name for the button.
1759 # Returns:
1760 #   A string containing a <INPUT TYPE="submit" NAME=".defaults"> tag
1761 #
1762 # Note: this button has a special meaning to the initialization script,
1763 # and tells it to ERASE the current query string so that your defaults
1764 # are used again!
1765 ####
1766 'defaults' => <<'END_OF_FUNC',
1767 sub defaults {
1768     my($self,@p) = self_or_default(@_);
1769
1770     my($label,@other) = rearrange([[NAME,VALUE]],@p);
1771
1772     $label=$self->escapeHTML($label,1);
1773     $label = $label || "Defaults";
1774     my($value) = qq/ value="$label"/;
1775     my($other) = @other ? " @other" : '';
1776     return $XHTML ? qq(<input type="submit" name=".defaults"$value$other />)
1777                   : qq/<input type="submit" NAME=".defaults"$value$other>/;
1778 }
1779 END_OF_FUNC
1780
1781
1782 #### Method: comment
1783 # Create an HTML <!-- comment -->
1784 # Parameters: a string
1785 'comment' => <<'END_OF_FUNC',
1786 sub comment {
1787     my($self,@p) = self_or_CGI(@_);
1788     return "<!-- @p -->";
1789 }
1790 END_OF_FUNC
1791
1792 #### Method: checkbox
1793 # Create a checkbox that is not logically linked to any others.
1794 # The field value is "on" when the button is checked.
1795 # Parameters:
1796 #   $name -> Name of the checkbox
1797 #   $checked -> (optional) turned on by default if true
1798 #   $value -> (optional) value of the checkbox, 'on' by default
1799 #   $label -> (optional) a user-readable label printed next to the box.
1800 #             Otherwise the checkbox name is used.
1801 # Returns:
1802 #   A string containing a <INPUT TYPE="checkbox"> field
1803 ####
1804 'checkbox' => <<'END_OF_FUNC',
1805 sub checkbox {
1806     my($self,@p) = self_or_default(@_);
1807
1808     my($name,$checked,$value,$label,$override,@other) =
1809         rearrange([NAME,[CHECKED,SELECTED,ON],VALUE,LABEL,[OVERRIDE,FORCE]],@p);
1810
1811     $value = defined $value ? $value : 'on';
1812
1813     if (!$override && ($self->{'.fieldnames'}->{$name} ||
1814                        defined $self->param($name))) {
1815         $checked = grep($_ eq $value,$self->param($name)) ? ' checked' : '';
1816     } else {
1817         $checked = $checked ? qq/ checked/ : '';
1818     }
1819     my($the_label) = defined $label ? $label : $name;
1820     $name = $self->escapeHTML($name);
1821     $value = $self->escapeHTML($value,1);
1822     $the_label = $self->escapeHTML($the_label);
1823     my($other) = @other ? " @other" : '';
1824     $self->register_parameter($name);
1825     return $XHTML ? qq{<input type="checkbox" name="$name" value="$value"$checked$other />$the_label}
1826                   : qq{<input type="checkbox" name="$name" value="$value"$checked$other>$the_label};
1827 }
1828 END_OF_FUNC
1829
1830
1831 #### Method: checkbox_group
1832 # Create a list of logically-linked checkboxes.
1833 # Parameters:
1834 #   $name -> Common name for all the check boxes
1835 #   $values -> A pointer to a regular array containing the
1836 #             values for each checkbox in the group.
1837 #   $defaults -> (optional)
1838 #             1. If a pointer to a regular array of checkbox values,
1839 #             then this will be used to decide which
1840 #             checkboxes to turn on by default.
1841 #             2. If a scalar, will be assumed to hold the
1842 #             value of a single checkbox in the group to turn on.
1843 #   $linebreak -> (optional) Set to true to place linebreaks
1844 #             between the buttons.
1845 #   $labels -> (optional)
1846 #             A pointer to an associative array of labels to print next to each checkbox
1847 #             in the form $label{'value'}="Long explanatory label".
1848 #             Otherwise the provided values are used as the labels.
1849 # Returns:
1850 #   An ARRAY containing a series of <INPUT TYPE="checkbox"> fields
1851 ####
1852 'checkbox_group' => <<'END_OF_FUNC',
1853 sub checkbox_group {
1854     my($self,@p) = self_or_default(@_);
1855
1856     my($name,$values,$defaults,$linebreak,$labels,$rows,$columns,
1857        $rowheaders,$colheaders,$override,$nolabels,@other) =
1858         rearrange([NAME,[VALUES,VALUE],[DEFAULTS,DEFAULT],
1859                           LINEBREAK,LABELS,ROWS,[COLUMNS,COLS],
1860                           ROWHEADERS,COLHEADERS,
1861                           [OVERRIDE,FORCE],NOLABELS],@p);
1862
1863     my($checked,$break,$result,$label);
1864
1865     my(%checked) = $self->previous_or_default($name,$defaults,$override);
1866
1867         if ($linebreak) {
1868     $break = $XHTML ? "<br />" : "<br>";
1869         }
1870         else {
1871         $break = '';
1872         }
1873     $name=$self->escapeHTML($name);
1874
1875     # Create the elements
1876     my(@elements,@values);
1877
1878     @values = $self->_set_values_and_labels($values,\$labels,$name);
1879
1880     my($other) = @other ? " @other" : '';
1881     foreach (@values) {
1882         $checked = $checked{$_} ? qq/ checked/ : '';
1883         $label = '';
1884         unless (defined($nolabels) && $nolabels) {
1885             $label = $_;
1886             $label = $labels->{$_} if defined($labels) && defined($labels->{$_});
1887             $label = $self->escapeHTML($label);
1888         }
1889         $_ = $self->escapeHTML($_,1);
1890         push(@elements,$XHTML ? qq(<input type="checkbox" name="$name" value="$_"$checked$other />${label}${break})
1891                               : qq/<input type="checkbox" name="$name" value="$_"$checked$other>${label}${break}/);
1892     }
1893     $self->register_parameter($name);
1894     return wantarray ? @elements : join(' ',@elements)
1895         unless defined($columns) || defined($rows);
1896     return _tableize($rows,$columns,$rowheaders,$colheaders,@elements);
1897 }
1898 END_OF_FUNC
1899
1900 # Escape HTML -- used internally
1901 'escapeHTML' => <<'END_OF_FUNC',
1902 sub escapeHTML {
1903          my ($self,$toencode,$newlinestoo) = CGI::self_or_default(@_);
1904          return undef unless defined($toencode);
1905          return $toencode if ref($self) && $self->{'dontescape'};
1906          $toencode =~ s{&}{&amp;}gso;
1907          $toencode =~ s{<}{&lt;}gso;
1908          $toencode =~ s{>}{&gt;}gso;
1909          $toencode =~ s{"}{&quot;}gso;
1910          my $latin = uc $self->{'.charset'} eq 'ISO-8859-1' ||
1911                      uc $self->{'.charset'} eq 'WINDOWS-1252';
1912          if ($latin) {  # bug in some browsers
1913                 $toencode =~ s{'}{&#39;}gso;
1914                 $toencode =~ s{\x8b}{&#139;}gso;
1915                 $toencode =~ s{\x9b}{&#155;}gso;
1916                 if (defined $newlinestoo && $newlinestoo) {
1917                      $toencode =~ s{\012}{&#10;}gso;
1918                      $toencode =~ s{\015}{&#13;}gso;
1919                 }
1920          }
1921          return $toencode;
1922 }
1923 END_OF_FUNC
1924
1925 # unescape HTML -- used internally
1926 'unescapeHTML' => <<'END_OF_FUNC',
1927 sub unescapeHTML {
1928     my ($self,$string) = CGI::self_or_default(@_);
1929     return undef unless defined($string);
1930     my $latin = defined $self->{'.charset'} ? $self->{'.charset'} =~ /^(ISO-8859-1|WINDOWS-1252)$/i
1931                                             : 1;
1932     # thanks to Randal Schwartz for the correct solution to this one
1933     $string=~ s[&(.*?);]{
1934         local $_ = $1;
1935         /^amp$/i        ? "&" :
1936         /^quot$/i       ? '"' :
1937         /^gt$/i         ? ">" :
1938         /^lt$/i         ? "<" :
1939         /^#(\d+)$/ && $latin         ? chr($1) :
1940         /^#x([0-9a-f]+)$/i && $latin ? chr(hex($1)) :
1941         $_
1942         }gex;
1943     return $string;
1944 }
1945 END_OF_FUNC
1946
1947 # Internal procedure - don't use
1948 '_tableize' => <<'END_OF_FUNC',
1949 sub _tableize {
1950     my($rows,$columns,$rowheaders,$colheaders,@elements) = @_;
1951     $rowheaders = [] unless defined $rowheaders;
1952     $colheaders = [] unless defined $colheaders;
1953     my($result);
1954
1955     if (defined($columns)) {
1956         $rows = int(0.99 + @elements/$columns) unless defined($rows);
1957     }
1958     if (defined($rows)) {
1959         $columns = int(0.99 + @elements/$rows) unless defined($columns);
1960     }
1961
1962     # rearrange into a pretty table
1963     $result = "<table>";
1964     my($row,$column);
1965     unshift(@$colheaders,'') if @$colheaders && @$rowheaders;
1966     $result .= "<tr>" if @{$colheaders};
1967     foreach (@{$colheaders}) {
1968         $result .= "<th>$_</th>";
1969     }
1970     for ($row=0;$row<$rows;$row++) {
1971         $result .= "<tr>";
1972         $result .= "<th>$rowheaders->[$row]</th>" if @$rowheaders;
1973         for ($column=0;$column<$columns;$column++) {
1974             $result .= "<td>" . $elements[$column*$rows + $row] . "</td>"
1975                 if defined($elements[$column*$rows + $row]);
1976         }
1977         $result .= "</tr>";
1978     }
1979     $result .= "</table>";
1980     return $result;
1981 }
1982 END_OF_FUNC
1983
1984
1985 #### Method: radio_group
1986 # Create a list of logically-linked radio buttons.
1987 # Parameters:
1988 #   $name -> Common name for all the buttons.
1989 #   $values -> A pointer to a regular array containing the
1990 #             values for each button in the group.
1991 #   $default -> (optional) Value of the button to turn on by default.  Pass '-'
1992 #               to turn _nothing_ on.
1993 #   $linebreak -> (optional) Set to true to place linebreaks
1994 #             between the buttons.
1995 #   $labels -> (optional)
1996 #             A pointer to an associative array of labels to print next to each checkbox
1997 #             in the form $label{'value'}="Long explanatory label".
1998 #             Otherwise the provided values are used as the labels.
1999 # Returns:
2000 #   An ARRAY containing a series of <INPUT TYPE="radio"> fields
2001 ####
2002 'radio_group' => <<'END_OF_FUNC',
2003 sub radio_group {
2004     my($self,@p) = self_or_default(@_);
2005
2006     my($name,$values,$default,$linebreak,$labels,
2007        $rows,$columns,$rowheaders,$colheaders,$override,$nolabels,@other) =
2008         rearrange([NAME,[VALUES,VALUE],DEFAULT,LINEBREAK,LABELS,
2009                           ROWS,[COLUMNS,COLS],
2010                           ROWHEADERS,COLHEADERS,
2011                           [OVERRIDE,FORCE],NOLABELS],@p);
2012     my($result,$checked);
2013
2014     if (!$override && defined($self->param($name))) {
2015         $checked = $self->param($name);
2016     } else {
2017         $checked = $default;
2018     }
2019     my(@elements,@values);
2020     @values = $self->_set_values_and_labels($values,\$labels,$name);
2021
2022     # If no check array is specified, check the first by default
2023     $checked = $values[0] unless defined($checked) && $checked ne '';
2024     $name=$self->escapeHTML($name);
2025
2026     my($other) = @other ? " @other" : '';
2027     foreach (@values) {
2028         my($checkit) = $checked eq $_ ? qq/ checked/ : '';
2029         my($break);
2030         if ($linebreak) {
2031           $break = $XHTML ? "<br />" : "<br>";
2032         }
2033         else {
2034           $break = '';
2035         }
2036         my($label)='';
2037         unless (defined($nolabels) && $nolabels) {
2038             $label = $_;
2039             $label = $labels->{$_} if defined($labels) && defined($labels->{$_});
2040             $label = $self->escapeHTML($label,1);
2041         }
2042         $_=$self->escapeHTML($_);
2043         push(@elements,$XHTML ? qq(<input type="radio" name="$name" value="$_"$checkit$other />${label}${break})
2044                               : qq/<input type="radio" name="$name" value="$_"$checkit$other>${label}${break}/);
2045     }
2046     $self->register_parameter($name);
2047     return wantarray ? @elements : join(' ',@elements)
2048            unless defined($columns) || defined($rows);
2049     return _tableize($rows,$columns,$rowheaders,$colheaders,@elements);
2050 }
2051 END_OF_FUNC
2052
2053
2054 #### Method: popup_menu
2055 # Create a popup menu.
2056 # Parameters:
2057 #   $name -> Name for all the menu
2058 #   $values -> A pointer to a regular array containing the
2059 #             text of each menu item.
2060 #   $default -> (optional) Default item to display
2061 #   $labels -> (optional)
2062 #             A pointer to an associative array of labels to print next to each checkbox
2063 #             in the form $label{'value'}="Long explanatory label".
2064 #             Otherwise the provided values are used as the labels.
2065 # Returns:
2066 #   A string containing the definition of a popup menu.
2067 ####
2068 'popup_menu' => <<'END_OF_FUNC',
2069 sub popup_menu {
2070     my($self,@p) = self_or_default(@_);
2071
2072     my($name,$values,$default,$labels,$override,@other) =
2073         rearrange([NAME,[VALUES,VALUE],[DEFAULT,DEFAULTS],LABELS,[OVERRIDE,FORCE]],@p);
2074     my($result,$selected);
2075
2076     if (!$override && defined($self->param($name))) {
2077         $selected = $self->param($name);
2078     } else {
2079         $selected = $default;
2080     }
2081     $name=$self->escapeHTML($name);
2082     my($other) = @other ? " @other" : '';
2083
2084     my(@values);
2085     @values = $self->_set_values_and_labels($values,\$labels,$name);
2086
2087     $result = qq/<select name="$name"$other>\n/;
2088     foreach (@values) {
2089         my($selectit) = defined($selected) ? ($selected eq $_ ? qq/selected/ : '' ) : '';
2090         my($label) = $_;
2091         $label = $labels->{$_} if defined($labels) && defined($labels->{$_});
2092         my($value) = $self->escapeHTML($_);
2093         $label=$self->escapeHTML($label,1);
2094         $result .= "<option $selectit value=\"$value\">$label</option>\n";
2095     }
2096
2097     $result .= "</select>\n";
2098     return $result;
2099 }
2100 END_OF_FUNC
2101
2102
2103 #### Method: scrolling_list
2104 # Create a scrolling list.
2105 # Parameters:
2106 #   $name -> name for the list
2107 #   $values -> A pointer to a regular array containing the
2108 #             values for each option line in the list.
2109 #   $defaults -> (optional)
2110 #             1. If a pointer to a regular array of options,
2111 #             then this will be used to decide which
2112 #             lines to turn on by default.
2113 #             2. Otherwise holds the value of the single line to turn on.
2114 #   $size -> (optional) Size of the list.
2115 #   $multiple -> (optional) If set, allow multiple selections.
2116 #   $labels -> (optional)
2117 #             A pointer to an associative array of labels to print next to each checkbox
2118 #             in the form $label{'value'}="Long explanatory label".
2119 #             Otherwise the provided values are used as the labels.
2120 # Returns:
2121 #   A string containing the definition of a scrolling list.
2122 ####
2123 'scrolling_list' => <<'END_OF_FUNC',
2124 sub scrolling_list {
2125     my($self,@p) = self_or_default(@_);
2126     my($name,$values,$defaults,$size,$multiple,$labels,$override,@other)
2127         = rearrange([NAME,[VALUES,VALUE],[DEFAULTS,DEFAULT],
2128                             SIZE,MULTIPLE,LABELS,[OVERRIDE,FORCE]],@p);
2129
2130     my($result,@values);
2131     @values = $self->_set_values_and_labels($values,\$labels,$name);
2132
2133     $size = $size || scalar(@values);
2134
2135     my(%selected) = $self->previous_or_default($name,$defaults,$override);
2136     my($is_multiple) = $multiple ? qq/ multiple/ : '';
2137     my($has_size) = $size ? qq/ size="$size"/: '';
2138     my($other) = @other ? " @other" : '';
2139
2140     $name=$self->escapeHTML($name);
2141     $result = qq/<select name="$name"$has_size$is_multiple$other>\n/;
2142     foreach (@values) {
2143         my($selectit) = $selected{$_} ? qq/selected/ : '';
2144         my($label) = $_;
2145         $label = $labels->{$_} if defined($labels) && defined($labels->{$_});
2146         $label=$self->escapeHTML($label);
2147         my($value)=$self->escapeHTML($_,1);
2148         $result .= "<option $selectit value=\"$value\">$label</option>\n";
2149     }
2150     $result .= "</select>\n";
2151     $self->register_parameter($name);
2152     return $result;
2153 }
2154 END_OF_FUNC
2155
2156
2157 #### Method: hidden
2158 # Parameters:
2159 #   $name -> Name of the hidden field
2160 #   @default -> (optional) Initial values of field (may be an array)
2161 #      or
2162 #   $default->[initial values of field]
2163 # Returns:
2164 #   A string containing a <INPUT TYPE="hidden" NAME="name" VALUE="value">
2165 ####
2166 'hidden' => <<'END_OF_FUNC',
2167 sub hidden {
2168     my($self,@p) = self_or_default(@_);
2169
2170     # this is the one place where we departed from our standard
2171     # calling scheme, so we have to special-case (darn)
2172     my(@result,@value);
2173     my($name,$default,$override,@other) =
2174         rearrange([NAME,[DEFAULT,VALUE,VALUES],[OVERRIDE,FORCE]],@p);
2175
2176     my $do_override = 0;
2177     if ( ref($p[0]) || substr($p[0],0,1) eq '-') {
2178         @value = ref($default) ? @{$default} : $default;
2179         $do_override = $override;
2180     } else {
2181         foreach ($default,$override,@other) {
2182             push(@value,$_) if defined($_);
2183         }
2184     }
2185
2186     # use previous values if override is not set
2187     my @prev = $self->param($name);
2188     @value = @prev if !$do_override && @prev;
2189
2190     $name=$self->escapeHTML($name);
2191     foreach (@value) {
2192         $_ = defined($_) ? $self->escapeHTML($_,1) : '';
2193         push @result,$XHTML ? qq(<input type="hidden" name="$name" value="$_" />)
2194                             : qq(<input type="hidden" name="$name" value="$_">);
2195     }
2196     return wantarray ? @result : join('',@result);
2197 }
2198 END_OF_FUNC
2199
2200
2201 #### Method: image_button
2202 # Parameters:
2203 #   $name -> Name of the button
2204 #   $src ->  URL of the image source
2205 #   $align -> Alignment style (TOP, BOTTOM or MIDDLE)
2206 # Returns:
2207 #   A string containing a <INPUT TYPE="image" NAME="name" SRC="url" ALIGN="alignment">
2208 ####
2209 'image_button' => <<'END_OF_FUNC',
2210 sub image_button {
2211     my($self,@p) = self_or_default(@_);
2212
2213     my($name,$src,$alignment,@other) =
2214         rearrange([NAME,SRC,ALIGN],@p);
2215
2216     my($align) = $alignment ? " align=\U$alignment" : '';
2217     my($other) = @other ? " @other" : '';
2218     $name=$self->escapeHTML($name);
2219     return $XHTML ? qq(<input type="image" name="$name" src="$src"$align$other />)
2220                   : qq/<input type="image" name="$name" src="$src"$align$other>/;
2221 }
2222 END_OF_FUNC
2223
2224
2225 #### Method: self_url
2226 # Returns a URL containing the current script and all its
2227 # param/value pairs arranged as a query.  You can use this
2228 # to create a link that, when selected, will reinvoke the
2229 # script with all its state information preserved.
2230 ####
2231 'self_url' => <<'END_OF_FUNC',
2232 sub self_url {
2233     my($self,@p) = self_or_default(@_);
2234     return $self->url('-path_info'=>1,'-query'=>1,'-full'=>1,@p);
2235 }
2236 END_OF_FUNC
2237
2238
2239 # This is provided as a synonym to self_url() for people unfortunate
2240 # enough to have incorporated it into their programs already!
2241 'state' => <<'END_OF_FUNC',
2242 sub state {
2243     &self_url;
2244 }
2245 END_OF_FUNC
2246
2247
2248 #### Method: url
2249 # Like self_url, but doesn't return the query string part of
2250 # the URL.
2251 ####
2252 'url' => <<'END_OF_FUNC',
2253 sub url {
2254     my($self,@p) = self_or_default(@_);
2255     my ($relative,$absolute,$full,$path_info,$query,$base) =
2256         rearrange(['RELATIVE','ABSOLUTE','FULL',['PATH','PATH_INFO'],['QUERY','QUERY_STRING'],'BASE'],@p);
2257     my $url;
2258     $full++ if $base || !($relative || $absolute);
2259
2260     my $path = $self->path_info;
2261     my $script_name = $self->script_name;
2262
2263 # If anybody knows why I ever wrote this please tell me!
2264 #    if (exists($ENV{REQUEST_URI})) {
2265 #        my $index;
2266 #       $script_name = $ENV{REQUEST_URI};
2267 #        # strip query string
2268 #        substr($script_name,$index) = '' if ($index = index($script_name,'?')) >= 0;
2269 #        # and path
2270 #        if (exists($ENV{PATH_INFO})) {
2271 #           (my $encoded_path = $ENV{PATH_INFO}) =~ s!([^a-zA-Z0-9_./-])!uc sprintf("%%%02x",ord($1))!eg;;
2272 #           substr($script_name,$index) = '' if ($index = rindex($script_name,$encoded_path)) >= 0;
2273 #         }
2274 #    } else {
2275 #       $script_name = $self->script_name;
2276 #    }
2277
2278     if ($full) {
2279         my $protocol = $self->protocol();
2280         $url = "$protocol://";
2281         my $vh = http('host');
2282         if ($vh) {
2283             $url .= $vh;
2284         } else {
2285             $url .= server_name();
2286             my $port = $self->server_port;
2287             $url .= ":" . $port
2288                 unless (lc($protocol) eq 'http' && $port == 80)
2289                     || (lc($protocol) eq 'https' && $port == 443);
2290         }
2291         return $url if $base;
2292         $url .= $script_name;
2293     } elsif ($relative) {
2294         ($url) = $script_name =~ m!([^/]+)$!;
2295     } elsif ($absolute) {
2296         $url = $script_name;
2297     }
2298
2299     $url .= $path if $path_info and defined $path;
2300     $url .= "?" . $self->query_string if $query and $self->query_string;
2301     $url = '' unless defined $url;
2302     $url =~ s/([^a-zA-Z0-9_.%;&?\/\\:+=~-])/uc sprintf("%%%02x",ord($1))/eg;
2303     return $url;
2304 }
2305
2306 END_OF_FUNC
2307
2308 #### Method: cookie
2309 # Set or read a cookie from the specified name.
2310 # Cookie can then be passed to header().
2311 # Usual rules apply to the stickiness of -value.
2312 #  Parameters:
2313 #   -name -> name for this cookie (optional)
2314 #   -value -> value of this cookie (scalar, array or hash)
2315 #   -path -> paths for which this cookie is valid (optional)
2316 #   -domain -> internet domain in which this cookie is valid (optional)
2317 #   -secure -> if true, cookie only passed through secure channel (optional)
2318 #   -expires -> expiry date in format Wdy, DD-Mon-YYYY HH:MM:SS GMT (optional)
2319 ####
2320 'cookie' => <<'END_OF_FUNC',
2321 sub cookie {
2322     my($self,@p) = self_or_default(@_);
2323     my($name,$value,$path,$domain,$secure,$expires) =
2324         rearrange([NAME,[VALUE,VALUES],PATH,DOMAIN,SECURE,EXPIRES],@p);
2325
2326     require CGI::Cookie;
2327
2328     # if no value is supplied, then we retrieve the
2329     # value of the cookie, if any.  For efficiency, we cache the parsed
2330     # cookies in our state variables.
2331     unless ( defined($value) ) {
2332         $self->{'.cookies'} = CGI::Cookie->fetch
2333             unless $self->{'.cookies'};
2334
2335         # If no name is supplied, then retrieve the names of all our cookies.
2336         return () unless $self->{'.cookies'};
2337         return keys %{$self->{'.cookies'}} unless $name;
2338         return () unless $self->{'.cookies'}->{$name};
2339         return $self->{'.cookies'}->{$name}->value if defined($name) && $name ne '';
2340     }
2341
2342     # If we get here, we're creating a new cookie
2343     return undef unless defined($name) && $name ne '';  # this is an error
2344
2345     my @param;
2346     push(@param,'-name'=>$name);
2347     push(@param,'-value'=>$value);
2348     push(@param,'-domain'=>$domain) if $domain;
2349     push(@param,'-path'=>$path) if $path;
2350     push(@param,'-expires'=>$expires) if $expires;
2351     push(@param,'-secure'=>$secure) if $secure;
2352
2353     return new CGI::Cookie(@param);
2354 }
2355 END_OF_FUNC
2356
2357 'parse_keywordlist' => <<'END_OF_FUNC',
2358 sub parse_keywordlist {
2359     my($self,$tosplit) = @_;
2360     $tosplit = unescape($tosplit); # unescape the keywords
2361     $tosplit=~tr/+/ /;          # pluses to spaces
2362     my(@keywords) = split(/\s+/,$tosplit);
2363     return @keywords;
2364 }
2365 END_OF_FUNC
2366
2367 'param_fetch' => <<'END_OF_FUNC',
2368 sub param_fetch {
2369     my($self,@p) = self_or_default(@_);
2370     my($name) = rearrange([NAME],@p);
2371     unless (exists($self->{$name})) {
2372         $self->add_parameter($name);
2373         $self->{$name} = [];
2374     }
2375
2376     return $self->{$name};
2377 }
2378 END_OF_FUNC
2379
2380 ###############################################
2381 # OTHER INFORMATION PROVIDED BY THE ENVIRONMENT
2382 ###############################################
2383
2384 #### Method: path_info
2385 # Return the extra virtual path information provided
2386 # after the URL (if any)
2387 ####
2388 'path_info' => <<'END_OF_FUNC',
2389 sub path_info {
2390     my ($self,$info) = self_or_default(@_);
2391     if (defined($info)) {
2392         $info = "/$info" if $info ne '' &&  substr($info,0,1) ne '/';
2393         $self->{'.path_info'} = $info;
2394     } elsif (! defined($self->{'.path_info'}) ) {
2395         $self->{'.path_info'} = defined($ENV{'PATH_INFO'}) ?
2396             $ENV{'PATH_INFO'} : '';
2397
2398         # hack to fix broken path info in IIS
2399         $self->{'.path_info'} =~ s/^\Q$ENV{'SCRIPT_NAME'}\E// if $IIS;
2400
2401     }
2402     return $self->{'.path_info'};
2403 }
2404 END_OF_FUNC
2405
2406
2407 #### Method: request_method
2408 # Returns 'POST', 'GET', 'PUT' or 'HEAD'
2409 ####
2410 'request_method' => <<'END_OF_FUNC',
2411 sub request_method {
2412     return $ENV{'REQUEST_METHOD'};
2413 }
2414 END_OF_FUNC
2415
2416 #### Method: content_type
2417 # Returns the content_type string
2418 ####
2419 'content_type' => <<'END_OF_FUNC',
2420 sub content_type {
2421     return $ENV{'CONTENT_TYPE'};
2422 }
2423 END_OF_FUNC
2424
2425 #### Method: path_translated
2426 # Return the physical path information provided
2427 # by the URL (if any)
2428 ####
2429 'path_translated' => <<'END_OF_FUNC',
2430 sub path_translated {
2431     return $ENV{'PATH_TRANSLATED'};
2432 }
2433 END_OF_FUNC
2434
2435
2436 #### Method: query_string
2437 # Synthesize a query string from our current
2438 # parameters
2439 ####
2440 'query_string' => <<'END_OF_FUNC',
2441 sub query_string {
2442     my($self) = self_or_default(@_);
2443     my($param,$value,@pairs);
2444     foreach $param ($self->param) {
2445         my($eparam) = escape($param);
2446         foreach $value ($self->param($param)) {
2447             $value = escape($value);
2448             next unless defined $value;
2449             push(@pairs,"$eparam=$value");
2450         }
2451     }
2452     foreach (keys %{$self->{'.fieldnames'}}) {
2453       push(@pairs,".cgifields=".escape("$_"));
2454     }
2455     return join($USE_PARAM_SEMICOLONS ? ';' : '&',@pairs);
2456 }
2457 END_OF_FUNC
2458
2459
2460 #### Method: accept
2461 # Without parameters, returns an array of the
2462 # MIME types the browser accepts.
2463 # With a single parameter equal to a MIME
2464 # type, will return undef if the browser won't
2465 # accept it, 1 if the browser accepts it but
2466 # doesn't give a preference, or a floating point
2467 # value between 0.0 and 1.0 if the browser
2468 # declares a quantitative score for it.
2469 # This handles MIME type globs correctly.
2470 ####
2471 'Accept' => <<'END_OF_FUNC',
2472 sub Accept {
2473     my($self,$search) = self_or_CGI(@_);
2474     my(%prefs,$type,$pref,$pat);
2475
2476     my(@accept) = split(',',$self->http('accept'));
2477
2478     foreach (@accept) {
2479         ($pref) = /q=(\d\.\d+|\d+)/;
2480         ($type) = m#(\S+/[^;]+)#;
2481         next unless $type;
2482         $prefs{$type}=$pref || 1;
2483     }
2484
2485     return keys %prefs unless $search;
2486
2487     # if a search type is provided, we may need to
2488     # perform a pattern matching operation.
2489     # The MIME types use a glob mechanism, which
2490     # is easily translated into a perl pattern match
2491
2492     # First return the preference for directly supported
2493     # types:
2494     return $prefs{$search} if $prefs{$search};
2495
2496     # Didn't get it, so try pattern matching.
2497     foreach (keys %prefs) {
2498         next unless /\*/;       # not a pattern match
2499         ($pat = $_) =~ s/([^\w*])/\\$1/g; # escape meta characters
2500         $pat =~ s/\*/.*/g; # turn it into a pattern
2501         return $prefs{$_} if $search=~/$pat/;
2502     }
2503 }
2504 END_OF_FUNC
2505
2506
2507 #### Method: user_agent
2508 # If called with no parameters, returns the user agent.
2509 # If called with one parameter, does a pattern match (case
2510 # insensitive) on the user agent.
2511 ####
2512 'user_agent' => <<'END_OF_FUNC',
2513 sub user_agent {
2514     my($self,$match)=self_or_CGI(@_);
2515     return $self->http('user_agent') unless $match;
2516     return $self->http('user_agent') =~ /$match/i;
2517 }
2518 END_OF_FUNC
2519
2520
2521 #### Method: raw_cookie
2522 # Returns the magic cookies for the session.
2523 # The cookies are not parsed or altered in any way, i.e.
2524 # cookies are returned exactly as given in the HTTP
2525 # headers.  If a cookie name is given, only that cookie's
2526 # value is returned, otherwise the entire raw cookie
2527 # is returned.
2528 ####
2529 'raw_cookie' => <<'END_OF_FUNC',
2530 sub raw_cookie {
2531     my($self,$key) = self_or_CGI(@_);
2532
2533     require CGI::Cookie;
2534
2535     if (defined($key)) {
2536         $self->{'.raw_cookies'} = CGI::Cookie->raw_fetch
2537             unless $self->{'.raw_cookies'};
2538
2539         return () unless $self->{'.raw_cookies'};
2540         return () unless $self->{'.raw_cookies'}->{$key};
2541         return $self->{'.raw_cookies'}->{$key};
2542     }
2543     return $self->http('cookie') || $ENV{'COOKIE'} || '';
2544 }
2545 END_OF_FUNC
2546
2547 #### Method: virtual_host
2548 # Return the name of the virtual_host, which
2549 # is not always the same as the server
2550 ######
2551 'virtual_host' => <<'END_OF_FUNC',
2552 sub virtual_host {
2553     my $vh = http('host') || server_name();
2554     $vh =~ s/:\d+$//;           # get rid of port number
2555     return $vh;
2556 }
2557 END_OF_FUNC
2558
2559 #### Method: remote_host
2560 # Return the name of the remote host, or its IP
2561 # address if unavailable.  If this variable isn't
2562 # defined, it returns "localhost" for debugging
2563 # purposes.
2564 ####
2565 'remote_host' => <<'END_OF_FUNC',
2566 sub remote_host {
2567     return $ENV{'REMOTE_HOST'} || $ENV{'REMOTE_ADDR'}
2568     || 'localhost';
2569 }
2570 END_OF_FUNC
2571
2572
2573 #### Method: remote_addr
2574 # Return the IP addr of the remote host.
2575 ####
2576 'remote_addr' => <<'END_OF_FUNC',
2577 sub remote_addr {
2578     return $ENV{'REMOTE_ADDR'} || '127.0.0.1';
2579 }
2580 END_OF_FUNC
2581
2582
2583 #### Method: script_name
2584 # Return the partial URL to this script for
2585 # self-referencing scripts.  Also see
2586 # self_url(), which returns a URL with all state information
2587 # preserved.
2588 ####
2589 'script_name' => <<'END_OF_FUNC',
2590 sub script_name {
2591     return $ENV{'SCRIPT_NAME'} if defined($ENV{'SCRIPT_NAME'});
2592     # These are for debugging
2593     return "/$0" unless $0=~/^\//;
2594     return $0;
2595 }
2596 END_OF_FUNC
2597
2598
2599 #### Method: referer
2600 # Return the HTTP_REFERER: useful for generating
2601 # a GO BACK button.
2602 ####
2603 'referer' => <<'END_OF_FUNC',
2604 sub referer {
2605     my($self) = self_or_CGI(@_);
2606     return $self->http('referer');
2607 }
2608 END_OF_FUNC
2609
2610
2611 #### Method: server_name
2612 # Return the name of the server
2613 ####
2614 'server_name' => <<'END_OF_FUNC',
2615 sub server_name {
2616     return $ENV{'SERVER_NAME'} || 'localhost';
2617 }
2618 END_OF_FUNC
2619
2620 #### Method: server_software
2621 # Return the name of the server software
2622 ####
2623 'server_software' => <<'END_OF_FUNC',
2624 sub server_software {
2625     return $ENV{'SERVER_SOFTWARE'} || 'cmdline';
2626 }
2627 END_OF_FUNC
2628
2629 #### Method: server_port
2630 # Return the tcp/ip port the server is running on
2631 ####
2632 'server_port' => <<'END_OF_FUNC',
2633 sub server_port {
2634     return $ENV{'SERVER_PORT'} || 80; # for debugging
2635 }
2636 END_OF_FUNC
2637
2638 #### Method: server_protocol
2639 # Return the protocol (usually HTTP/1.0)
2640 ####
2641 'server_protocol' => <<'END_OF_FUNC',
2642 sub server_protocol {
2643     return $ENV{'SERVER_PROTOCOL'} || 'HTTP/1.0'; # for debugging
2644 }
2645 END_OF_FUNC
2646
2647 #### Method: http
2648 # Return the value of an HTTP variable, or
2649 # the list of variables if none provided
2650 ####
2651 'http' => <<'END_OF_FUNC',
2652 sub http {
2653     my ($self,$parameter) = self_or_CGI(@_);
2654     return $ENV{$parameter} if $parameter=~/^HTTP/;
2655     $parameter =~ tr/-/_/;
2656     return $ENV{"HTTP_\U$parameter\E"} if $parameter;
2657     my(@p);
2658     foreach (keys %ENV) {
2659         push(@p,$_) if /^HTTP/;
2660     }
2661     return @p;
2662 }
2663 END_OF_FUNC
2664
2665 #### Method: https
2666 # Return the value of HTTPS
2667 ####
2668 'https' => <<'END_OF_FUNC',
2669 sub https {
2670     local($^W)=0;
2671     my ($self,$parameter) = self_or_CGI(@_);
2672     return $ENV{HTTPS} unless $parameter;
2673     return $ENV{$parameter} if $parameter=~/^HTTPS/;
2674     $parameter =~ tr/-/_/;
2675     return $ENV{"HTTPS_\U$parameter\E"} if $parameter;
2676     my(@p);
2677     foreach (keys %ENV) {
2678         push(@p,$_) if /^HTTPS/;
2679     }
2680     return @p;
2681 }
2682 END_OF_FUNC
2683
2684 #### Method: protocol
2685 # Return the protocol (http or https currently)
2686 ####
2687 'protocol' => <<'END_OF_FUNC',
2688 sub protocol {
2689     local($^W)=0;
2690     my $self = shift;
2691     return 'https' if uc($self->https()) eq 'ON';
2692     return 'https' if $self->server_port == 443;
2693     my $prot = $self->server_protocol;
2694     my($protocol,$version) = split('/',$prot);
2695     return "\L$protocol\E";
2696 }
2697 END_OF_FUNC
2698
2699 #### Method: remote_ident
2700 # Return the identity of the remote user
2701 # (but only if his host is running identd)
2702 ####
2703 'remote_ident' => <<'END_OF_FUNC',
2704 sub remote_ident {
2705     return $ENV{'REMOTE_IDENT'};
2706 }
2707 END_OF_FUNC
2708
2709
2710 #### Method: auth_type
2711 # Return the type of use verification/authorization in use, if any.
2712 ####
2713 'auth_type' => <<'END_OF_FUNC',
2714 sub auth_type {
2715     return $ENV{'AUTH_TYPE'};
2716 }
2717 END_OF_FUNC
2718
2719
2720 #### Method: remote_user
2721 # Return the authorization name used for user
2722 # verification.
2723 ####
2724 'remote_user' => <<'END_OF_FUNC',
2725 sub remote_user {
2726     return $ENV{'REMOTE_USER'};
2727 }
2728 END_OF_FUNC
2729
2730
2731 #### Method: user_name
2732 # Try to return the remote user's name by hook or by
2733 # crook
2734 ####
2735 'user_name' => <<'END_OF_FUNC',
2736 sub user_name {
2737     my ($self) = self_or_CGI(@_);
2738     return $self->http('from') || $ENV{'REMOTE_IDENT'} || $ENV{'REMOTE_USER'};
2739 }
2740 END_OF_FUNC
2741
2742 #### Method: nosticky
2743 # Set or return the NOSTICKY global flag
2744 ####
2745 'nosticky' => <<'END_OF_FUNC',
2746 sub nosticky {
2747     my ($self,$param) = self_or_CGI(@_);
2748     $CGI::NOSTICKY = $param if defined($param);
2749     return $CGI::NOSTICKY;
2750 }
2751 END_OF_FUNC
2752
2753 #### Method: nph
2754 # Set or return the NPH global flag
2755 ####
2756 'nph' => <<'END_OF_FUNC',
2757 sub nph {
2758     my ($self,$param) = self_or_CGI(@_);
2759     $CGI::NPH = $param if defined($param);
2760     return $CGI::NPH;
2761 }
2762 END_OF_FUNC
2763
2764 #### Method: private_tempfiles
2765 # Set or return the private_tempfiles global flag
2766 ####
2767 'private_tempfiles' => <<'END_OF_FUNC',
2768 sub private_tempfiles {
2769     my ($self,$param) = self_or_CGI(@_);
2770     $CGI::PRIVATE_TEMPFILES = $param if defined($param);
2771     return $CGI::PRIVATE_TEMPFILES;
2772 }
2773 END_OF_FUNC
2774
2775 #### Method: default_dtd
2776 # Set or return the default_dtd global
2777 ####
2778 'default_dtd' => <<'END_OF_FUNC',
2779 sub default_dtd {
2780     my ($self,$param,$param2) = self_or_CGI(@_);
2781     if (defined $param2 && defined $param) {
2782         $CGI::DEFAULT_DTD = [ $param, $param2 ];
2783     } elsif (defined $param) {
2784         $CGI::DEFAULT_DTD = $param;
2785     }
2786     return $CGI::DEFAULT_DTD;
2787 }
2788 END_OF_FUNC
2789
2790 # -------------- really private subroutines -----------------
2791 'previous_or_default' => <<'END_OF_FUNC',
2792 sub previous_or_default {
2793     my($self,$name,$defaults,$override) = @_;
2794     my(%selected);
2795
2796     if (!$override && ($self->{'.fieldnames'}->{$name} ||
2797                        defined($self->param($name)) ) ) {
2798         grep($selected{$_}++,$self->param($name));
2799     } elsif (defined($defaults) && ref($defaults) &&
2800              (ref($defaults) eq 'ARRAY')) {
2801         grep($selected{$_}++,@{$defaults});
2802     } else {
2803         $selected{$defaults}++ if defined($defaults);
2804     }
2805
2806     return %selected;
2807 }
2808 END_OF_FUNC
2809
2810 'register_parameter' => <<'END_OF_FUNC',
2811 sub register_parameter {
2812     my($self,$param) = @_;
2813     $self->{'.parametersToAdd'}->{$param}++;
2814 }
2815 END_OF_FUNC
2816
2817 'get_fields' => <<'END_OF_FUNC',
2818 sub get_fields {
2819     my($self) = @_;
2820     return $self->CGI::hidden('-name'=>'.cgifields',
2821                               '-values'=>[keys %{$self->{'.parametersToAdd'}}],
2822                               '-override'=>1);
2823 }
2824 END_OF_FUNC
2825
2826 'read_from_cmdline' => <<'END_OF_FUNC',
2827 sub read_from_cmdline {
2828     my($input,@words);
2829     my($query_string);
2830     if ($DEBUG && @ARGV) {
2831         @words = @ARGV;
2832     } elsif ($DEBUG > 1) {
2833         require "shellwords.pl";
2834         print STDERR "(offline mode: enter name=value pairs on standard input)\n";
2835         chomp(@lines = <STDIN>); # remove newlines
2836         $input = join(" ",@lines);
2837         @words = &shellwords($input);
2838     }
2839     foreach (@words) {
2840         s/\\=/%3D/g;
2841         s/\\&/%26/g;
2842     }
2843
2844     if ("@words"=~/=/) {
2845         $query_string = join('&',@words);
2846     } else {
2847         $query_string = join('+',@words);
2848     }
2849     return $query_string;
2850 }
2851 END_OF_FUNC
2852
2853 #####
2854 # subroutine: read_multipart
2855 #
2856 # Read multipart data and store it into our parameters.
2857 # An interesting feature is that if any of the parts is a file, we
2858 # create a temporary file and open up a filehandle on it so that the
2859 # caller can read from it if necessary.
2860 #####
2861 'read_multipart' => <<'END_OF_FUNC',
2862 sub read_multipart {
2863     my($self,$boundary,$length,$filehandle) = @_;
2864     my($buffer) = $self->new_MultipartBuffer($boundary,$length,$filehandle);
2865     return unless $buffer;
2866     my(%header,$body);
2867     my $filenumber = 0;
2868     while (!$buffer->eof) {
2869         %header = $buffer->readHeader;
2870
2871         unless (%header) {
2872             $self->cgi_error("400 Bad request (malformed multipart POST)");
2873             return;
2874         }
2875
2876         my($param)= $header{'Content-Disposition'}=~/ name="?([^\";]*)"?/;
2877
2878         # Bug:  Netscape doesn't escape quotation marks in file names!!!
2879         my($filename) = $header{'Content-Disposition'}=~/ filename="?([^\"]*)"?/;
2880
2881         # add this parameter to our list
2882         $self->add_parameter($param);
2883
2884         # If no filename specified, then just read the data and assign it
2885         # to our parameter list.
2886         if ( !defined($filename) || $filename eq '' ) {
2887             my($value) = $buffer->readBody;
2888             push(@{$self->{$param}},$value);
2889             next;
2890         }
2891
2892         my ($tmpfile,$tmp,$filehandle);
2893       UPLOADS: {
2894           # If we get here, then we are dealing with a potentially large
2895           # uploaded form.  Save the data to a temporary file, then open
2896           # the file for reading.
2897
2898           # skip the file if uploads disabled
2899           if ($DISABLE_UPLOADS) {
2900               while (defined($data = $buffer->read)) { }
2901               last UPLOADS;
2902           }
2903
2904           # choose a relatively unpredictable tmpfile sequence number
2905           my $seqno = unpack("%16C*",join('',localtime,values %ENV));
2906           for (my $cnt=10;$cnt>0;$cnt--) {
2907             next unless $tmpfile = new TempFile($seqno);
2908             $tmp = $tmpfile->as_string;
2909             last if defined($filehandle = Fh->new($filename,$tmp,$PRIVATE_TEMPFILES));
2910             $seqno += int rand(100);
2911           }
2912           die "CGI open of tmpfile: $!\n" unless $filehandle;
2913           $CGI::DefaultClass->binmode($filehandle) if $CGI::needs_binmode;
2914
2915           my ($data);
2916           local($\) = '';
2917           while (defined($data = $buffer->read)) {
2918               print $filehandle $data;
2919           }
2920
2921           # back up to beginning of file
2922           seek($filehandle,0,0);
2923           $CGI::DefaultClass->binmode($filehandle) if $CGI::needs_binmode;
2924
2925           # Save some information about the uploaded file where we can get
2926           # at it later.
2927           $self->{'.tmpfiles'}->{fileno($filehandle)}= {
2928               name => $tmpfile,
2929               info => {%header},
2930           };
2931           push(@{$self->{$param}},$filehandle);
2932       }
2933     }
2934 }
2935 END_OF_FUNC
2936
2937 'upload' =><<'END_OF_FUNC',
2938 sub upload {
2939     my($self,$param_name) = self_or_default(@_);
2940     my $param = $self->param($param_name);
2941     return unless $param;
2942     return unless ref($param) && fileno($param);
2943     return $param;
2944 }
2945 END_OF_FUNC
2946
2947 'tmpFileName' => <<'END_OF_FUNC',
2948 sub tmpFileName {
2949     my($self,$filename) = self_or_default(@_);
2950     return $self->{'.tmpfiles'}->{fileno($filename)}->{name} ?
2951         $self->{'.tmpfiles'}->{fileno($filename)}->{name}->as_string
2952             : '';
2953 }
2954 END_OF_FUNC
2955
2956 'uploadInfo' => <<'END_OF_FUNC',
2957 sub uploadInfo {
2958     my($self,$filename) = self_or_default(@_);
2959     return $self->{'.tmpfiles'}->{fileno($filename)}->{info};
2960 }
2961 END_OF_FUNC
2962
2963 # internal routine, don't use
2964 '_set_values_and_labels' => <<'END_OF_FUNC',
2965 sub _set_values_and_labels {
2966     my $self = shift;
2967     my ($v,$l,$n) = @_;
2968     $$l = $v if ref($v) eq 'HASH' && !ref($$l);
2969     return $self->param($n) if !defined($v);
2970     return $v if !ref($v);
2971     return ref($v) eq 'HASH' ? keys %$v : @$v;
2972 }
2973 END_OF_FUNC
2974
2975 '_compile_all' => <<'END_OF_FUNC',
2976 sub _compile_all {
2977     foreach (@_) {
2978         next if defined(&$_);
2979         $AUTOLOAD = "CGI::$_";
2980         _compile();
2981     }
2982 }
2983 END_OF_FUNC
2984
2985 );
2986 END_OF_AUTOLOAD
2987 ;
2988
2989 #########################################################
2990 # Globals and stubs for other packages that we use.
2991 #########################################################
2992
2993 ################### Fh -- lightweight filehandle ###############
2994 package Fh;
2995 use overload
2996     '""'  => \&asString,
2997     'cmp' => \&compare,
2998     'fallback'=>1;
2999
3000 $FH='fh00000';
3001
3002 *Fh::AUTOLOAD = \&CGI::AUTOLOAD;
3003
3004 $AUTOLOADED_ROUTINES = '';      # prevent -w error
3005 $AUTOLOADED_ROUTINES=<<'END_OF_AUTOLOAD';
3006 %SUBS =  (
3007 'asString' => <<'END_OF_FUNC',
3008 sub asString {
3009     my $self = shift;
3010     # get rid of package name
3011     (my $i = $$self) =~ s/^\*(\w+::fh\d{5})+//;
3012     $i =~ s/%(..)/ chr(hex($1)) /eg;
3013     return $i;
3014 # BEGIN DEAD CODE
3015 # This was an extremely clever patch that allowed "use strict refs".
3016 # Unfortunately it relied on another bug that caused leaky file descriptors.
3017 # The underlying bug has been fixed, so this no longer works.  However
3018 # "strict refs" still works for some reason.
3019 #    my $self = shift;
3020 #    return ${*{$self}{SCALAR}};
3021 # END DEAD CODE
3022 }
3023 END_OF_FUNC
3024
3025 'compare' => <<'END_OF_FUNC',
3026 sub compare {
3027     my $self = shift;
3028     my $value = shift;
3029     return "$self" cmp $value;
3030 }
3031 END_OF_FUNC
3032
3033 'new'  => <<'END_OF_FUNC',
3034 sub new {
3035     my($pack,$name,$file,$delete) = @_;
3036     require Fcntl unless defined &Fcntl::O_RDWR;
3037     (my $safename = $name) =~ s/([':%])/ sprintf '%%%02X', ord $1 /eg;
3038     my $fv = ++$FH . $safename;
3039     my $ref = \*{"Fh::$fv"};
3040     sysopen($ref,$file,Fcntl::O_RDWR()|Fcntl::O_CREAT()|Fcntl::O_EXCL(),0600) || return;
3041     unlink($file) if $delete;
3042     CORE::delete $Fh::{$fv};
3043     return bless $ref,$pack;
3044 }
3045 END_OF_FUNC
3046
3047 'DESTROY'  => <<'END_OF_FUNC',
3048 sub DESTROY {
3049     my $self = shift;
3050     close $self;
3051 }
3052 END_OF_FUNC
3053
3054 );
3055 END_OF_AUTOLOAD
3056
3057 ######################## MultipartBuffer ####################
3058 package MultipartBuffer;
3059
3060 # how many bytes to read at a time.  We use
3061 # a 4K buffer by default.
3062 $INITIAL_FILLUNIT = 1024 * 4;
3063 $TIMEOUT = 240*60;       # 4 hour timeout for big files
3064 $SPIN_LOOP_MAX = 2000;  # bug fix for some Netscape servers
3065 $CRLF=$CGI::CRLF;
3066
3067 #reuse the autoload function
3068 *MultipartBuffer::AUTOLOAD = \&CGI::AUTOLOAD;
3069
3070 # avoid autoloader warnings
3071 sub DESTROY {}
3072
3073 ###############################################################################
3074 ################# THESE FUNCTIONS ARE AUTOLOADED ON DEMAND ####################
3075 ###############################################################################
3076 $AUTOLOADED_ROUTINES = '';      # prevent -w error
3077 $AUTOLOADED_ROUTINES=<<'END_OF_AUTOLOAD';
3078 %SUBS =  (
3079
3080 'new' => <<'END_OF_FUNC',
3081 sub new {
3082     my($package,$interface,$boundary,$length,$filehandle) = @_;
3083     $FILLUNIT = $INITIAL_FILLUNIT;
3084     my $IN;
3085     if ($filehandle) {
3086         my($package) = caller;
3087         # force into caller's package if necessary
3088         $IN = $filehandle=~/[':]/ ? $filehandle : "$package\:\:$filehandle";
3089     }
3090     $IN = "main::STDIN" unless $IN;
3091
3092     $CGI::DefaultClass->binmode($IN) if $CGI::needs_binmode;
3093
3094     # If the user types garbage into the file upload field,
3095     # then Netscape passes NOTHING to the server (not good).
3096     # We may hang on this read in that case. So we implement
3097     # a read timeout.  If nothing is ready to read
3098     # by then, we return.
3099
3100     # Netscape seems to be a little bit unreliable
3101     # about providing boundary strings.
3102     my $boundary_read = 0;
3103     if ($boundary) {
3104
3105         # Under the MIME spec, the boundary consists of the
3106         # characters "--" PLUS the Boundary string
3107
3108         # BUG: IE 3.01 on the Macintosh uses just the boundary -- not
3109         # the two extra hyphens.  We do a special case here on the user-agent!!!!
3110         $boundary = "--$boundary" unless CGI::user_agent('MSIE\s+3\.0[12];\s*Mac');
3111
3112     } else { # otherwise we find it ourselves
3113         my($old);
3114         ($old,$/) = ($/,$CRLF); # read a CRLF-delimited line
3115         $boundary = <$IN>;      # BUG: This won't work correctly under mod_perl
3116         $length -= length($boundary);
3117         chomp($boundary);               # remove the CRLF
3118         $/ = $old;                      # restore old line separator
3119         $boundary_read++;
3120     }
3121
3122     my $self = {LENGTH=>$length,
3123                 BOUNDARY=>$boundary,
3124                 IN=>$IN,
3125                 INTERFACE=>$interface,
3126                 BUFFER=>'',
3127             };
3128
3129     $FILLUNIT = length($boundary)
3130         if length($boundary) > $FILLUNIT;
3131
3132     my $retval = bless $self,ref $package || $package;
3133
3134     # Read the preamble and the topmost (boundary) line plus the CRLF.
3135     unless ($boundary_read) {
3136       while ($self->read(0)) { }
3137     }
3138     die "Malformed multipart POST\n" if $self->eof;
3139
3140     return $retval;
3141 }
3142 END_OF_FUNC
3143
3144 'readHeader' => <<'END_OF_FUNC',
3145 sub readHeader {
3146     my($self) = @_;
3147     my($end);
3148     my($ok) = 0;
3149     my($bad) = 0;
3150
3151     local($CRLF) = "\015\012" if $CGI::OS eq 'VMS';
3152
3153     do {
3154         $self->fillBuffer($FILLUNIT);
3155         $ok++ if ($end = index($self->{BUFFER},"${CRLF}${CRLF}")) >= 0;
3156         $ok++ if $self->{BUFFER} eq '';
3157         $bad++ if !$ok && $self->{LENGTH} <= 0;
3158         # this was a bad idea
3159         # $FILLUNIT *= 2 if length($self->{BUFFER}) >= $FILLUNIT;
3160     } until $ok || $bad;
3161     return () if $bad;
3162
3163     my($header) = substr($self->{BUFFER},0,$end+2);
3164     substr($self->{BUFFER},0,$end+4) = '';
3165     my %return;
3166
3167
3168     # See RFC 2045 Appendix A and RFC 822 sections 3.4.8
3169     #   (Folding Long Header Fields), 3.4.3 (Comments)
3170     #   and 3.4.5 (Quoted-Strings).
3171
3172     my $token = '[-\w!\#$%&\'*+.^_\`|{}~]';
3173     $header=~s/$CRLF\s+/ /og;           # merge continuation lines
3174     while ($header=~/($token+):\s+([^$CRLF]*)/mgox) {
3175         my ($field_name,$field_value) = ($1,$2); # avoid taintedness
3176         $field_name =~ s/\b(\w)/uc($1)/eg; #canonicalize
3177         $return{$field_name}=$field_value;
3178     }
3179     return %return;
3180 }
3181 END_OF_FUNC
3182
3183 # This reads and returns the body as a single scalar value.
3184 'readBody' => <<'END_OF_FUNC',
3185 sub readBody {
3186     my($self) = @_;
3187     my($data);
3188     my($returnval)='';
3189     while (defined($data = $self->read)) {
3190         $returnval .= $data;
3191     }
3192     return $returnval;
3193 }
3194 END_OF_FUNC
3195
3196 # This will read $bytes or until the boundary is hit, whichever happens
3197 # first.  After the boundary is hit, we return undef.  The next read will
3198 # skip over the boundary and begin reading again;
3199 'read' => <<'END_OF_FUNC',
3200 sub read {
3201     my($self,$bytes) = @_;
3202
3203     # default number of bytes to read
3204     $bytes = $bytes || $FILLUNIT;
3205
3206     # Fill up our internal buffer in such a way that the boundary
3207     # is never split between reads.
3208     $self->fillBuffer($bytes);
3209
3210     # Find the boundary in the buffer (it may not be there).
3211     my $start = index($self->{BUFFER},$self->{BOUNDARY});
3212     # protect against malformed multipart POST operations
3213     die "Malformed multipart POST\n" unless ($start >= 0) || ($self->{LENGTH} > 0);
3214
3215     # If the boundary begins the data, then skip past it
3216     # and return undef.
3217     if ($start == 0) {
3218
3219         # clear us out completely if we've hit the last boundary.
3220         if (index($self->{BUFFER},"$self->{BOUNDARY}--")==0) {
3221             $self->{BUFFER}='';
3222             $self->{LENGTH}=0;
3223             return undef;
3224         }
3225
3226         # just remove the boundary.
3227         substr($self->{BUFFER},0,length($self->{BOUNDARY}))='';
3228         $self->{BUFFER} =~ s/^\012\015?//;
3229         return undef;
3230     }
3231
3232     my $bytesToReturn;
3233     if ($start > 0) {           # read up to the boundary
3234         $bytesToReturn = $start > $bytes ? $bytes : $start;
3235     } else {    # read the requested number of bytes
3236         # leave enough bytes in the buffer to allow us to read
3237         # the boundary.  Thanks to Kevin Hendrick for finding
3238         # this one.
3239         $bytesToReturn = $bytes - (length($self->{BOUNDARY})+1);
3240     }
3241
3242     my $returnval=substr($self->{BUFFER},0,$bytesToReturn);
3243     substr($self->{BUFFER},0,$bytesToReturn)='';
3244
3245     # If we hit the boundary, remove the CRLF from the end.
3246     return ($start > 0) ? substr($returnval,0,-2) : $returnval;
3247 }
3248 END_OF_FUNC
3249
3250
3251 # This fills up our internal buffer in such a way that the
3252 # boundary is never split between reads
3253 'fillBuffer' => <<'END_OF_FUNC',
3254 sub fillBuffer {
3255     my($self,$bytes) = @_;
3256     return unless $self->{LENGTH};
3257
3258     my($boundaryLength) = length($self->{BOUNDARY});
3259     my($bufferLength) = length($self->{BUFFER});
3260     my($bytesToRead) = $bytes - $bufferLength + $boundaryLength + 2;
3261     $bytesToRead = $self->{LENGTH} if $self->{LENGTH} < $bytesToRead;
3262
3263     # Try to read some data.  We may hang here if the browser is screwed up.
3264     my $bytesRead = $self->{INTERFACE}->read_from_client($self->{IN},
3265                                                          \$self->{BUFFER},
3266                                                          $bytesToRead,
3267                                                          $bufferLength);
3268     $self->{BUFFER} = '' unless defined $self->{BUFFER};
3269
3270     # An apparent bug in the Apache server causes the read()
3271     # to return zero bytes repeatedly without blocking if the
3272     # remote user aborts during a file transfer.  I don't know how
3273     # they manage this, but the workaround is to abort if we get
3274     # more than SPIN_LOOP_MAX consecutive zero reads.
3275     if ($bytesRead == 0) {
3276         die  "CGI.pm: Server closed socket during multipart read (client aborted?).\n"
3277             if ($self->{ZERO_LOOP_COUNTER}++ >= $SPIN_LOOP_MAX);
3278     } else {
3279         $self->{ZERO_LOOP_COUNTER}=0;
3280     }
3281
3282     $self->{LENGTH} -= $bytesRead;
3283 }
3284 END_OF_FUNC
3285
3286
3287 # Return true when we've finished reading
3288 'eof' => <<'END_OF_FUNC'
3289 sub eof {
3290     my($self) = @_;
3291     return 1 if (length($self->{BUFFER}) == 0)
3292                  && ($self->{LENGTH} <= 0);
3293     undef;
3294 }
3295 END_OF_FUNC
3296
3297 );
3298 END_OF_AUTOLOAD
3299
3300 ####################################################################################
3301 ################################## TEMPORARY FILES #################################
3302 ####################################################################################
3303 package TempFile;
3304
3305 $SL = $CGI::SL;
3306 $MAC = $CGI::OS eq 'MACINTOSH';
3307 my ($vol) = $MAC ? MacPerl::Volumes() =~ /:(.*)/ : "";
3308 unless ($TMPDIRECTORY) {
3309     @TEMP=("${SL}usr${SL}tmp","${SL}var${SL}tmp",
3310            "C:${SL}temp","${SL}tmp","${SL}temp",
3311            "${vol}${SL}Temporary Items",
3312            "${SL}WWW_ROOT", "${SL}SYS\$SCRATCH",
3313            "C:${SL}system${SL}temp");
3314     unshift(@TEMP,$ENV{'TMPDIR'}) if exists $ENV{'TMPDIR'};
3315
3316     # this feature was supposed to provide per-user tmpfiles, but
3317     # it is problematic.
3318     #    unshift(@TEMP,(getpwuid($<))[7].'/tmp') if $CGI::OS eq 'UNIX';
3319     # Rob: getpwuid() is unfortunately UNIX specific. On brain dead OS'es this
3320     #    : can generate a 'getpwuid() not implemented' exception, even though
3321     #    : it's never called.  Found under DOS/Win with the DJGPP perl port.
3322     #    : Refer to getpwuid() only at run-time if we're fortunate and have  UNIX.
3323     # unshift(@TEMP,(eval {(getpwuid($>))[7]}).'/tmp') if $CGI::OS eq 'UNIX' and $> != 0;
3324
3325     foreach (@TEMP) {
3326         do {$TMPDIRECTORY = $_; last} if -d $_ && -w _;
3327     }
3328 }
3329
3330 $TMPDIRECTORY  = $MAC ? "" : "." unless $TMPDIRECTORY;
3331 $MAXTRIES = 5000;
3332
3333 # cute feature, but overload implementation broke it
3334 # %OVERLOAD = ('""'=>'as_string');
3335 *TempFile::AUTOLOAD = \&CGI::AUTOLOAD;
3336
3337 ###############################################################################
3338 ################# THESE FUNCTIONS ARE AUTOLOADED ON DEMAND ####################
3339 ###############################################################################
3340 $AUTOLOADED_ROUTINES = '';      # prevent -w error
3341 $AUTOLOADED_ROUTINES=<<'END_OF_AUTOLOAD';
3342 %SUBS = (
3343
3344 'new' => <<'END_OF_FUNC',
3345 sub new {
3346     my($package,$sequence) = @_;
3347     my $filename;
3348     for (my $i = 0; $i < $MAXTRIES; $i++) {
3349         last if ! -f ($filename = sprintf("${TMPDIRECTORY}${SL}CGItemp%d",$sequence++));
3350     }
3351     # untaint the darn thing
3352     return unless $filename =~ m!^([a-zA-Z0-9_ '":/.\$\\-]+)$!;
3353     $filename = $1;
3354     return bless \$filename;
3355 }
3356 END_OF_FUNC
3357
3358 'DESTROY' => <<'END_OF_FUNC',
3359 sub DESTROY {
3360     my($self) = @_;
3361     unlink $$self;              # get rid of the file
3362 }
3363 END_OF_FUNC
3364
3365 'as_string' => <<'END_OF_FUNC'
3366 sub as_string {
3367     my($self) = @_;
3368     return $$self;
3369 }
3370 END_OF_FUNC
3371
3372 );
3373 END_OF_AUTOLOAD
3374
3375 package CGI;
3376
3377 # We get a whole bunch of warnings about "possibly uninitialized variables"
3378 # when running with the -w switch.  Touch them all once to get rid of the
3379 # warnings.  This is ugly and I hate it.
3380 if ($^W) {
3381     $CGI::CGI = '';
3382     $CGI::CGI=<<EOF;
3383     $CGI::VERSION;
3384     $MultipartBuffer::SPIN_LOOP_MAX;
3385     $MultipartBuffer::CRLF;
3386     $MultipartBuffer::TIMEOUT;
3387     $MultipartBuffer::INITIAL_FILLUNIT;
3388 EOF
3389     ;
3390 }
3391
3392 1;
3393
3394 __END__
3395
3396 =head1 NAME
3397
3398 CGI - Simple Common Gateway Interface Class
3399
3400 =head1 SYNOPSIS
3401
3402   # CGI script that creates a fill-out form
3403   # and echoes back its values.
3404
3405   use CGI qw/:standard/;
3406   print header,
3407         start_html('A Simple Example'),
3408         h1('A Simple Example'),
3409         start_form,
3410         "What's your name? ",textfield('name'),p,
3411         "What's the combination?", p,
3412         checkbox_group(-name=>'words',
3413                        -values=>['eenie','meenie','minie','moe'],
3414                        -defaults=>['eenie','minie']), p,
3415         "What's your favorite color? ",
3416         popup_menu(-name=>'color',
3417                    -values=>['red','green','blue','chartreuse']),p,
3418         submit,
3419         end_form,
3420         hr;
3421
3422    if (param()) {
3423        print "Your name is",em(param('name')),p,
3424              "The keywords are: ",em(join(", ",param('words'))),p,
3425              "Your favorite color is ",em(param('color')),
3426              hr;
3427    }
3428
3429 =head1 ABSTRACT
3430
3431 This perl library uses perl5 objects to make it easy to create Web
3432 fill-out forms and parse their contents.  This package defines CGI
3433 objects, entities that contain the values of the current query string
3434 and other state variables.  Using a CGI object's methods, you can
3435 examine keywords and parameters passed to your script, and create
3436 forms whose initial values are taken from the current query (thereby
3437 preserving state information).  The module provides shortcut functions
3438 that produce boilerplate HTML, reducing typing and coding errors. It
3439 also provides functionality for some of the more advanced features of
3440 CGI scripting, including support for file uploads, cookies, cascading
3441 style sheets, server push, and frames.
3442
3443 CGI.pm also provides a simple function-oriented programming style for
3444 those who don't need its object-oriented features.
3445
3446 The current version of CGI.pm is available at
3447
3448   http://www.genome.wi.mit.edu/ftp/pub/software/WWW/cgi_docs.html
3449   ftp://ftp-genome.wi.mit.edu/pub/software/WWW/
3450
3451 =head1 DESCRIPTION
3452
3453 =head2 PROGRAMMING STYLE
3454
3455 There are two styles of programming with CGI.pm, an object-oriented
3456 style and a function-oriented style.  In the object-oriented style you
3457 create one or more CGI objects and then use object methods to create
3458 the various elements of the page.  Each CGI object starts out with the
3459 list of named parameters that were passed to your CGI script by the
3460 server.  You can modify the objects, save them to a file or database
3461 and recreate them.  Because each object corresponds to the "state" of
3462 the CGI script, and because each object's parameter list is
3463 independent of the others, this allows you to save the state of the
3464 script and restore it later.
3465
3466 For example, using the object oriented style, here is how you create
3467 a simple "Hello World" HTML page:
3468
3469    #!/usr/local/bin/perl -w
3470    use CGI;                             # load CGI routines
3471    $q = new CGI;                        # create new CGI object
3472    print $q->header,                    # create the HTTP header
3473          $q->start_html('hello world'), # start the HTML
3474          $q->h1('hello world'),         # level 1 header
3475          $q->end_html;                  # end the HTML
3476
3477 In the function-oriented style, there is one default CGI object that
3478 you rarely deal with directly.  Instead you just call functions to
3479 retrieve CGI parameters, create HTML tags, manage cookies, and so
3480 on.  This provides you with a cleaner programming interface, but
3481 limits you to using one CGI object at a time.  The following example
3482 prints the same page, but uses the function-oriented interface.
3483 The main differences are that we now need to import a set of functions
3484 into our name space (usually the "standard" functions), and we don't
3485 need to create the CGI object.
3486
3487    #!/usr/local/bin/perl
3488    use CGI qw/:standard/;           # load standard CGI routines
3489    print header,                    # create the HTTP header
3490          start_html('hello world'), # start the HTML
3491          h1('hello world'),         # level 1 header
3492          end_html;                  # end the HTML
3493
3494 The examples in this document mainly use the object-oriented style.
3495 See HOW TO IMPORT FUNCTIONS for important information on
3496 function-oriented programming in CGI.pm
3497
3498 =head2 CALLING CGI.PM ROUTINES
3499
3500 Most CGI.pm routines accept several arguments, sometimes as many as 20
3501 optional ones!  To simplify this interface, all routines use a named
3502 argument calling style that looks like this:
3503
3504    print $q->header(-type=>'image/gif',-expires=>'+3d');
3505
3506 Each argument name is preceded by a dash.  Neither case nor order
3507 matters in the argument list.  -type, -Type, and -TYPE are all
3508 acceptable.  In fact, only the first argument needs to begin with a
3509 dash.  If a dash is present in the first argument, CGI.pm assumes
3510 dashes for the subsequent ones.
3511
3512 Several routines are commonly called with just one argument.  In the
3513 case of these routines you can provide the single argument without an
3514 argument name.  header() happens to be one of these routines.  In this
3515 case, the single argument is the document type.
3516
3517    print $q->header('text/html');
3518
3519 Other such routines are documented below.
3520
3521 Sometimes named arguments expect a scalar, sometimes a reference to an
3522 array, and sometimes a reference to a hash.  Often, you can pass any
3523 type of argument and the routine will do whatever is most appropriate.
3524 For example, the param() routine is used to set a CGI parameter to a
3525 single or a multi-valued value.  The two cases are shown below:
3526
3527    $q->param(-name=>'veggie',-value=>'tomato');
3528    $q->param(-name=>'veggie',-value=>['tomato','tomahto','potato','potahto']);
3529
3530 A large number of routines in CGI.pm actually aren't specifically
3531 defined in the module, but are generated automatically as needed.
3532 These are the "HTML shortcuts," routines that generate HTML tags for
3533 use in dynamically-generated pages.  HTML tags have both attributes
3534 (the attribute="value" pairs within the tag itself) and contents (the
3535 part between the opening and closing pairs.)  To distinguish between
3536 attributes and contents, CGI.pm uses the convention of passing HTML
3537 attributes as a hash reference as the first argument, and the
3538 contents, if any, as any subsequent arguments.  It works out like
3539 this:
3540
3541    Code                           Generated HTML
3542    ----                           --------------
3543    h1()                           <H1>
3544    h1('some','contents');         <H1>some contents</H1>
3545    h1({-align=>left});            <H1 ALIGN="LEFT">
3546    h1({-align=>left},'contents'); <H1 ALIGN="LEFT">contents</H1>
3547
3548 HTML tags are described in more detail later.
3549
3550 Many newcomers to CGI.pm are puzzled by the difference between the
3551 calling conventions for the HTML shortcuts, which require curly braces
3552 around the HTML tag attributes, and the calling conventions for other
3553 routines, which manage to generate attributes without the curly
3554 brackets.  Don't be confused.  As a convenience the curly braces are
3555 optional in all but the HTML shortcuts.  If you like, you can use
3556 curly braces when calling any routine that takes named arguments.  For
3557 example:
3558
3559    print $q->header( {-type=>'image/gif',-expires=>'+3d'} );
3560
3561 If you use the B<-w> switch, you will be warned that some CGI.pm argument
3562 names conflict with built-in Perl functions.  The most frequent of
3563 these is the -values argument, used to create multi-valued menus,
3564 radio button clusters and the like.  To get around this warning, you
3565 have several choices:
3566
3567 =over 4
3568
3569 =item 1.
3570
3571 Use another name for the argument, if one is available.
3572 For example, -value is an alias for -values.
3573
3574 =item 2.
3575
3576 Change the capitalization, e.g. -Values
3577
3578 =item 3.
3579
3580 Put quotes around the argument name, e.g. '-values'
3581
3582 =back
3583
3584 Many routines will do something useful with a named argument that it
3585 doesn't recognize.  For example, you can produce non-standard HTTP
3586 header fields by providing them as named arguments:
3587
3588   print $q->header(-type  =>  'text/html',
3589                    -cost  =>  'Three smackers',
3590                    -annoyance_level => 'high',
3591                    -complaints_to   => 'bit bucket');
3592
3593 This will produce the following nonstandard HTTP header:
3594
3595    HTTP/1.0 200 OK
3596    Cost: Three smackers
3597    Annoyance-level: high
3598    Complaints-to: bit bucket
3599    Content-type: text/html
3600
3601 Notice the way that underscores are translated automatically into
3602 hyphens.  HTML-generating routines perform a different type of
3603 translation.
3604
3605 This feature allows you to keep up with the rapidly changing HTTP and
3606 HTML "standards".
3607
3608 =head2 CREATING A NEW QUERY OBJECT (OBJECT-ORIENTED STYLE):
3609
3610      $query = new CGI;
3611
3612 This will parse the input (from both POST and GET methods) and store
3613 it into a perl5 object called $query.
3614
3615 =head2 CREATING A NEW QUERY OBJECT FROM AN INPUT FILE
3616
3617      $query = new CGI(INPUTFILE);
3618
3619 If you provide a file handle to the new() method, it will read
3620 parameters from the file (or STDIN, or whatever).  The file can be in
3621 any of the forms describing below under debugging (i.e. a series of
3622 newline delimited TAG=VALUE pairs will work).  Conveniently, this type
3623 of file is created by the save() method (see below).  Multiple records
3624 can be saved and restored.
3625
3626 Perl purists will be pleased to know that this syntax accepts
3627 references to file handles, or even references to filehandle globs,
3628 which is the "official" way to pass a filehandle:
3629
3630     $query = new CGI(\*STDIN);
3631
3632 You can also initialize the CGI object with a FileHandle or IO::File
3633 object.
3634
3635 If you are using the function-oriented interface and want to
3636 initialize CGI state from a file handle, the way to do this is with
3637 B<restore_parameters()>.  This will (re)initialize the
3638 default CGI object from the indicated file handle.
3639
3640     open (IN,"test.in") || die;
3641     restore_parameters(IN);
3642     close IN;
3643
3644 You can also initialize the query object from an associative array
3645 reference:
3646
3647     $query = new CGI( {'dinosaur'=>'barney',
3648                        'song'=>'I love you',
3649                        'friends'=>[qw/Jessica George Nancy/]}
3650                     );
3651
3652 or from a properly formatted, URL-escaped query string:
3653
3654     $query = new CGI('dinosaur=barney&color=purple');
3655
3656 or from a previously existing CGI object (currently this clones the
3657 parameter list, but none of the other object-specific fields, such as
3658 autoescaping):
3659
3660     $old_query = new CGI;
3661     $new_query = new CGI($old_query);
3662
3663 To create an empty query, initialize it from an empty string or hash:
3664
3665    $empty_query = new CGI("");
3666
3667        -or-
3668
3669    $empty_query = new CGI({});
3670
3671 =head2 FETCHING A LIST OF KEYWORDS FROM THE QUERY:
3672
3673      @keywords = $query->keywords
3674
3675 If the script was invoked as the result of an <ISINDEX> search, the
3676 parsed keywords can be obtained as an array using the keywords() method.
3677
3678 =head2 FETCHING THE NAMES OF ALL THE PARAMETERS PASSED TO YOUR SCRIPT:
3679
3680      @names = $query->param
3681
3682 If the script was invoked with a parameter list
3683 (e.g. "name1=value1&name2=value2&name3=value3"), the param() method
3684 will return the parameter names as a list.  If the script was invoked
3685 as an <ISINDEX> script and contains a string without ampersands
3686 (e.g. "value1+value2+value3") , there will be a single parameter named
3687 "keywords" containing the "+"-delimited keywords.
3688
3689 NOTE: As of version 1.5, the array of parameter names returned will
3690 be in the same order as they were submitted by the browser.
3691 Usually this order is the same as the order in which the
3692 parameters are defined in the form (however, this isn't part
3693 of the spec, and so isn't guaranteed).
3694
3695 =head2 FETCHING THE VALUE OR VALUES OF A SINGLE NAMED PARAMETER:
3696
3697     @values = $query->param('foo');
3698
3699               -or-
3700
3701     $value = $query->param('foo');
3702
3703 Pass the param() method a single argument to fetch the value of the
3704 named parameter. If the parameter is multivalued (e.g. from multiple
3705 selections in a scrolling list), you can ask to receive an array.  Otherwise
3706 the method will return a single value.
3707
3708 If a value is not given in the query string, as in the queries
3709 "name1=&name2=" or "name1&name2", it will be returned as an empty
3710 string.  This feature is new in 2.63.
3711
3712 =head2 SETTING THE VALUE(S) OF A NAMED PARAMETER:
3713
3714     $query->param('foo','an','array','of','values');
3715
3716 This sets the value for the named parameter 'foo' to an array of
3717 values.  This is one way to change the value of a field AFTER
3718 the script has been invoked once before.  (Another way is with
3719 the -override parameter accepted by all methods that generate
3720 form elements.)
3721
3722 param() also recognizes a named parameter style of calling described
3723 in more detail later:
3724
3725     $query->param(-name=>'foo',-values=>['an','array','of','values']);
3726
3727                               -or-
3728
3729     $query->param(-name=>'foo',-value=>'the value');
3730
3731 =head2 APPENDING ADDITIONAL VALUES TO A NAMED PARAMETER:
3732
3733    $query->append(-name=>'foo',-values=>['yet','more','values']);
3734
3735 This adds a value or list of values to the named parameter.  The
3736 values are appended to the end of the parameter if it already exists.
3737 Otherwise the parameter is created.  Note that this method only
3738 recognizes the named argument calling syntax.
3739
3740 =head2 IMPORTING ALL PARAMETERS INTO A NAMESPACE:
3741
3742    $query->import_names('R');
3743
3744 This creates a series of variables in the 'R' namespace.  For example,
3745 $R::foo, @R:foo.  For keyword lists, a variable @R::keywords will appear.
3746 If no namespace is given, this method will assume 'Q'.
3747 WARNING:  don't import anything into 'main'; this is a major security
3748 risk!!!!
3749
3750 In older versions, this method was called B<import()>.  As of version 2.20,
3751 this name has been removed completely to avoid conflict with the built-in
3752 Perl module B<import> operator.
3753
3754 =head2 DELETING A PARAMETER COMPLETELY:
3755
3756     $query->delete('foo');
3757
3758 This completely clears a parameter.  It sometimes useful for
3759 resetting parameters that you don't want passed down between
3760 script invocations.
3761
3762 If you are using the function call interface, use "Delete()" instead
3763 to avoid conflicts with Perl's built-in delete operator.
3764
3765 =head2 DELETING ALL PARAMETERS:
3766
3767    $query->delete_all();
3768
3769 This clears the CGI object completely.  It might be useful to ensure
3770 that all the defaults are taken when you create a fill-out form.
3771
3772 Use Delete_all() instead if you are using the function call interface.
3773
3774 =head2 DIRECT ACCESS TO THE PARAMETER LIST:
3775
3776    $q->param_fetch('address')->[1] = '1313 Mockingbird Lane';
3777    unshift @{$q->param_fetch(-name=>'address')},'George Munster';
3778
3779 If you need access to the parameter list in a way that isn't covered
3780 by the methods above, you can obtain a direct reference to it by
3781 calling the B<param_fetch()> method with the name of the .  This
3782 will return an array reference to the named parameters, which you then
3783 can manipulate in any way you like.
3784
3785 You can also use a named argument style using the B<-name> argument.
3786
3787 =head2 FETCHING THE PARAMETER LIST AS A HASH:
3788
3789     $params = $q->Vars;
3790     print $params->{'address'};
3791     @foo = split("\0",$params->{'foo'});
3792     %params = $q->Vars;
3793
3794     use CGI ':cgi-lib';
3795     $params = Vars;
3796
3797 Many people want to fetch the entire parameter list as a hash in which
3798 the keys are the names of the CGI parameters, and the values are the
3799 parameters' values.  The Vars() method does this.  Called in a scalar
3800 context, it returns the parameter list as a tied hash reference.
3801 Changing a key changes the value of the parameter in the underlying
3802 CGI parameter list.  Called in a list context, it returns the
3803 parameter list as an ordinary hash.  This allows you to read the
3804 contents of the parameter list, but not to change it.
3805
3806 When using this, the thing you must watch out for are multivalued CGI
3807 parameters.  Because a hash cannot distinguish between scalar and
3808 list context, multivalued parameters will be returned as a packed
3809 string, separated by the "\0" (null) character.  You must split this
3810 packed string in order to get at the individual values.  This is the
3811 convention introduced long ago by Steve Brenner in his cgi-lib.pl
3812 module for Perl version 4.
3813
3814 If you wish to use Vars() as a function, import the I<:cgi-lib> set of
3815 function calls (also see the section on CGI-LIB compatibility).
3816
3817 =head2 SAVING THE STATE OF THE SCRIPT TO A FILE:
3818
3819     $query->save(FILEHANDLE)
3820
3821 This will write the current state of the form to the provided
3822 filehandle.  You can read it back in by providing a filehandle
3823 to the new() method.  Note that the filehandle can be a file, a pipe,
3824 or whatever!
3825
3826 The format of the saved file is:
3827
3828         NAME1=VALUE1
3829         NAME1=VALUE1'
3830         NAME2=VALUE2
3831         NAME3=VALUE3
3832         =
3833
3834 Both name and value are URL escaped.  Multi-valued CGI parameters are
3835 represented as repeated names.  A session record is delimited by a
3836 single = symbol.  You can write out multiple records and read them
3837 back in with several calls to B<new>.  You can do this across several
3838 sessions by opening the file in append mode, allowing you to create
3839 primitive guest books, or to keep a history of users' queries.  Here's
3840 a short example of creating multiple session records:
3841
3842    use CGI;
3843
3844    open (OUT,">>test.out") || die;
3845    $records = 5;
3846    foreach (0..$records) {
3847        my $q = new CGI;
3848        $q->param(-name=>'counter',-value=>$_);
3849        $q->save(OUT);
3850    }
3851    close OUT;
3852
3853    # reopen for reading
3854    open (IN,"test.out") || die;
3855    while (!eof(IN)) {
3856        my $q = new CGI(IN);
3857        print $q->param('counter'),"\n";
3858    }
3859
3860 The file format used for save/restore is identical to that used by the
3861 Whitehead Genome Center's data exchange format "Boulderio", and can be
3862 manipulated and even databased using Boulderio utilities.  See
3863
3864   http://stein.cshl.org/boulder/
3865
3866 for further details.
3867
3868 If you wish to use this method from the function-oriented (non-OO)
3869 interface, the exported name for this method is B<save_parameters()>.
3870
3871 =head2 RETRIEVING CGI ERRORS
3872
3873 Errors can occur while processing user input, particularly when
3874 processing uploaded files.  When these errors occur, CGI will stop
3875 processing and return an empty parameter list.  You can test for
3876 the existence and nature of errors using the I<cgi_error()> function.
3877 The error messages are formatted as HTTP status codes. You can either
3878 incorporate the error text into an HTML page, or use it as the value
3879 of the HTTP status:
3880
3881     my $error = $q->cgi_error;
3882     if ($error) {
3883         print $q->header(-status=>$error),
3884               $q->start_html('Problems'),
3885               $q->h2('Request not processed'),
3886               $q->strong($error);
3887         exit 0;
3888     }
3889
3890 When using the function-oriented interface (see the next section),
3891 errors may only occur the first time you call I<param()>. Be ready
3892 for this!
3893
3894 =head2 USING THE FUNCTION-ORIENTED INTERFACE
3895
3896 To use the function-oriented interface, you must specify which CGI.pm
3897 routines or sets of routines to import into your script's namespace.
3898 There is a small overhead associated with this importation, but it
3899 isn't much.
3900
3901    use CGI <list of methods>;
3902
3903 The listed methods will be imported into the current package; you can
3904 call them directly without creating a CGI object first.  This example
3905 shows how to import the B<param()> and B<header()>
3906 methods, and then use them directly:
3907
3908    use CGI 'param','header';
3909    print header('text/plain');
3910    $zipcode = param('zipcode');
3911
3912 More frequently, you'll import common sets of functions by referring
3913 to the groups by name.  All function sets are preceded with a ":"
3914 character as in ":html3" (for tags defined in the HTML 3 standard).
3915
3916 Here is a list of the function sets you can import:
3917
3918 =over 4
3919
3920 =item B<:cgi>
3921
3922 Import all CGI-handling methods, such as B<param()>, B<path_info()>
3923 and the like.
3924
3925 =item B<:form>
3926
3927 Import all fill-out form generating methods, such as B<textfield()>.
3928
3929 =item B<:html2>
3930
3931 Import all methods that generate HTML 2.0 standard elements.
3932
3933 =item B<:html3>
3934
3935 Import all methods that generate HTML 3.0 proposed elements (such as
3936 <table>, <super> and <sub>).
3937
3938 =item B<:netscape>
3939
3940 Import all methods that generate Netscape-specific HTML extensions.
3941
3942 =item B<:html>
3943
3944 Import all HTML-generating shortcuts (i.e. 'html2' + 'html3' +
3945 'netscape')...
3946
3947 =item B<:standard>
3948
3949 Import "standard" features, 'html2', 'html3', 'form' and 'cgi'.
3950
3951 =item B<:all>
3952
3953 Import all the available methods.  For the full list, see the CGI.pm
3954 code, where the variable %EXPORT_TAGS is defined.
3955
3956 =back
3957
3958 If you import a function name that is not part of CGI.pm, the module
3959 will treat it as a new HTML tag and generate the appropriate
3960 subroutine.  You can then use it like any other HTML tag.  This is to
3961 provide for the rapidly-evolving HTML "standard."  For example, say
3962 Microsoft comes out with a new tag called <GRADIENT> (which causes the
3963 user's desktop to be flooded with a rotating gradient fill until his
3964 machine reboots).  You don't need to wait for a new version of CGI.pm
3965 to start using it immediately:
3966
3967    use CGI qw/:standard :html3 gradient/;
3968    print gradient({-start=>'red',-end=>'blue'});
3969
3970 Note that in the interests of execution speed CGI.pm does B<not> use
3971 the standard L<Exporter> syntax for specifying load symbols.  This may
3972 change in the future.
3973
3974 If you import any of the state-maintaining CGI or form-generating
3975 methods, a default CGI object will be created and initialized
3976 automatically the first time you use any of the methods that require
3977 one to be present.  This includes B<param()>, B<textfield()>,
3978 B<submit()> and the like.  (If you need direct access to the CGI
3979 object, you can find it in the global variable B<$CGI::Q>).  By
3980 importing CGI.pm methods, you can create visually elegant scripts:
3981
3982    use CGI qw/:standard/;
3983    print
3984        header,
3985        start_html('Simple Script'),
3986        h1('Simple Script'),
3987        start_form,
3988        "What's your name? ",textfield('name'),p,
3989        "What's the combination?",
3990        checkbox_group(-name=>'words',
3991                       -values=>['eenie','meenie','minie','moe'],
3992                       -defaults=>['eenie','moe']),p,
3993        "What's your favorite color?",
3994        popup_menu(-name=>'color',
3995                   -values=>['red','green','blue','chartreuse']),p,
3996        submit,
3997        end_form,
3998        hr,"\n";
3999
4000     if (param) {
4001        print
4002            "Your name is ",em(param('name')),p,
4003            "The keywords are: ",em(join(", ",param('words'))),p,
4004            "Your favorite color is ",em(param('color')),".\n";
4005     }
4006     print end_html;
4007
4008 =head2 PRAGMAS
4009
4010 In addition to the function sets, there are a number of pragmas that
4011 you can import.  Pragmas, which are always preceded by a hyphen,
4012 change the way that CGI.pm functions in various ways.  Pragmas,
4013 function sets, and individual functions can all be imported in the
4014 same use() line.  For example, the following use statement imports the
4015 standard set of functions and enables debugging mode (pragma
4016 -debug):
4017
4018    use CGI qw/:standard -debug/;
4019
4020 The current list of pragmas is as follows:
4021
4022 =over 4
4023
4024 =item -any
4025
4026 When you I<use CGI -any>, then any method that the query object
4027 doesn't recognize will be interpreted as a new HTML tag.  This allows
4028 you to support the next I<ad hoc> Netscape or Microsoft HTML
4029 extension.  This lets you go wild with new and unsupported tags:
4030
4031    use CGI qw(-any);
4032    $q=new CGI;
4033    print $q->gradient({speed=>'fast',start=>'red',end=>'blue'});
4034
4035 Since using <cite>any</cite> causes any mistyped method name
4036 to be interpreted as an HTML tag, use it with care or not at
4037 all.
4038
4039 =item -compile
4040
4041 This causes the indicated autoloaded methods to be compiled up front,
4042 rather than deferred to later.  This is useful for scripts that run
4043 for an extended period of time under FastCGI or mod_perl, and for
4044 those destined to be crunched by Malcom Beattie's Perl compiler.  Use
4045 it in conjunction with the methods or method families you plan to use.
4046
4047    use CGI qw(-compile :standard :html3);
4048
4049 or even
4050
4051    use CGI qw(-compile :all);
4052
4053 Note that using the -compile pragma in this way will always have
4054 the effect of importing the compiled functions into the current
4055 namespace.  If you want to compile without importing use the
4056 compile() method instead (see below).
4057
4058 =item -nosticky
4059
4060 This makes CGI.pm not generating the hidden fields .submit
4061 and .cgifields. It is very useful if you don't want to
4062 have the hidden fields appear in the querystring in a GET method.
4063 For example, a search script generated this way will have
4064 a very nice url with search parameters for bookmarking.
4065
4066 =item -no_xhtml
4067
4068 By default, CGI.pm versions 2.69 and higher emit XHTML
4069 (http://www.w3.org/TR/xhtml1/).  The -no_xhtml pragma disables this
4070 feature.  Thanks to Michalis Kabrianis <kabrianis@hellug.gr> for this
4071 feature.
4072
4073 =item -nph
4074
4075 This makes CGI.pm produce a header appropriate for an NPH (no
4076 parsed header) script.  You may need to do other things as well
4077 to tell the server that the script is NPH.  See the discussion
4078 of NPH scripts below.
4079
4080 =item -newstyle_urls
4081
4082 Separate the name=value pairs in CGI parameter query strings with
4083 semicolons rather than ampersands.  For example:
4084
4085    ?name=fred;age=24;favorite_color=3
4086
4087 Semicolon-delimited query strings are always accepted, but will not be
4088 emitted by self_url() and query_string() unless the -newstyle_urls
4089 pragma is specified.
4090
4091 This became the default in version 2.64.
4092
4093 =item -oldstyle_urls
4094
4095 Separate the name=value pairs in CGI parameter query strings with
4096 ampersands rather than semicolons.  This is no longer the default.
4097
4098 =item -autoload
4099
4100 This overrides the autoloader so that any function in your program
4101 that is not recognized is referred to CGI.pm for possible evaluation.
4102 This allows you to use all the CGI.pm functions without adding them to
4103 your symbol table, which is of concern for mod_perl users who are
4104 worried about memory consumption.  I<Warning:> when
4105 I<-autoload> is in effect, you cannot use "poetry mode"
4106 (functions without the parenthesis).  Use I<hr()> rather
4107 than I<hr>, or add something like I<use subs qw/hr p header/>
4108 to the top of your script.
4109
4110 =item -no_debug
4111
4112 This turns off the command-line processing features.  If you want to
4113 run a CGI.pm script from the command line to produce HTML, and you
4114 don't want it to read CGI parameters from the command line or STDIN,
4115 then use this pragma:
4116
4117    use CGI qw(-no_debug :standard);
4118
4119 =item -debug
4120
4121 This turns on full debugging.  In addition to reading CGI arguments
4122 from the command-line processing, CGI.pm will pause and try to read
4123 arguments from STDIN, producing the message "(offline mode: enter
4124 name=value pairs on standard input)" features.
4125
4126 See the section on debugging for more details.
4127
4128 =item -private_tempfiles
4129
4130 CGI.pm can process uploaded file. Ordinarily it spools the uploaded
4131 file to a temporary directory, then deletes the file when done.
4132 However, this opens the risk of eavesdropping as described in the file
4133 upload section.  Another CGI script author could peek at this data
4134 during the upload, even if it is confidential information. On Unix
4135 systems, the -private_tempfiles pragma will cause the temporary file
4136 to be unlinked as soon as it is opened and before any data is written
4137 into it, reducing, but not eliminating the risk of eavesdropping
4138 (there is still a potential race condition).  To make life harder for
4139 the attacker, the program chooses tempfile names by calculating a 32
4140 bit checksum of the incoming HTTP headers.
4141
4142 To ensure that the temporary file cannot be read by other CGI scripts,
4143 use suEXEC or a CGI wrapper program to run your script.  The temporary
4144 file is created with mode 0600 (neither world nor group readable).
4145
4146 The temporary directory is selected using the following algorithm:
4147
4148     1. if the current user (e.g. "nobody") has a directory named
4149     "tmp" in its home directory, use that (Unix systems only).
4150
4151     2. if the environment variable TMPDIR exists, use the location
4152     indicated.
4153
4154     3. Otherwise try the locations /usr/tmp, /var/tmp, C:\temp,
4155     /tmp, /temp, ::Temporary Items, and \WWW_ROOT.
4156
4157 Each of these locations is checked that it is a directory and is
4158 writable.  If not, the algorithm tries the next choice.
4159
4160 =back
4161
4162 =head2 SPECIAL FORMS FOR IMPORTING HTML-TAG FUNCTIONS
4163
4164 Many of the methods generate HTML tags.  As described below, tag
4165 functions automatically generate both the opening and closing tags.
4166 For example:
4167
4168   print h1('Level 1 Header');
4169
4170 produces
4171
4172   <H1>Level 1 Header</H1>
4173
4174 There will be some times when you want to produce the start and end
4175 tags yourself.  In this case, you can use the form start_I<tag_name>
4176 and end_I<tag_name>, as in:
4177
4178   print start_h1,'Level 1 Header',end_h1;
4179
4180 With a few exceptions (described below), start_I<tag_name> and
4181 end_I<tag_name> functions are not generated automatically when you
4182 I<use CGI>.  However, you can specify the tags you want to generate
4183 I<start/end> functions for by putting an asterisk in front of their
4184 name, or, alternatively, requesting either "start_I<tag_name>" or
4185 "end_I<tag_name>" in the import list.
4186
4187 Example:
4188
4189   use CGI qw/:standard *table start_ul/;
4190
4191 In this example, the following functions are generated in addition to
4192 the standard ones:
4193
4194 =over 4
4195
4196 =item 1. start_table() (generates a <TABLE> tag)
4197
4198 =item 2. end_table() (generates a </TABLE> tag)
4199
4200 =item 3. start_ul() (generates a <UL> tag)
4201
4202 =item 4. end_ul() (generates a </UL> tag)
4203
4204 =back
4205
4206 =head1 GENERATING DYNAMIC DOCUMENTS
4207
4208 Most of CGI.pm's functions deal with creating documents on the fly.
4209 Generally you will produce the HTTP header first, followed by the
4210 document itself.  CGI.pm provides functions for generating HTTP
4211 headers of various types as well as for generating HTML.  For creating
4212 GIF images, see the GD.pm module.
4213
4214 Each of these functions produces a fragment of HTML or HTTP which you
4215 can print out directly so that it displays in the browser window,
4216 append to a string, or save to a file for later use.
4217
4218 =head2 CREATING A STANDARD HTTP HEADER:
4219
4220 Normally the first thing you will do in any CGI script is print out an
4221 HTTP header.  This tells the browser what type of document to expect,
4222 and gives other optional information, such as the language, expiration
4223 date, and whether to cache the document.  The header can also be
4224 manipulated for special purposes, such as server push and pay per view
4225 pages.
4226
4227         print $query->header;
4228
4229              -or-
4230
4231         print $query->header('image/gif');
4232
4233              -or-
4234
4235         print $query->header('text/html','204 No response');
4236
4237              -or-
4238
4239         print $query->header(-type=>'image/gif',
4240                              -nph=>1,
4241                              -status=>'402 Payment required',
4242                              -expires=>'+3d',
4243                              -cookie=>$cookie,
4244                              -charset=>'utf-7',
4245                              -attachment=>'foo.gif',
4246                              -Cost=>'$2.00');
4247
4248 header() returns the Content-type: header.  You can provide your own
4249 MIME type if you choose, otherwise it defaults to text/html.  An
4250 optional second parameter specifies the status code and a human-readable
4251 message.  For example, you can specify 204, "No response" to create a
4252 script that tells the browser to do nothing at all.
4253
4254 The last example shows the named argument style for passing arguments
4255 to the CGI methods using named parameters.  Recognized parameters are
4256 B<-type>, B<-status>, B<-expires>, and B<-cookie>.  Any other named
4257 parameters will be stripped of their initial hyphens and turned into
4258 header fields, allowing you to specify any HTTP header you desire.
4259 Internal underscores will be turned into hyphens:
4260
4261     print $query->header(-Content_length=>3002);
4262
4263 Most browsers will not cache the output from CGI scripts.  Every time
4264 the browser reloads the page, the script is invoked anew.  You can
4265 change this behavior with the B<-expires> parameter.  When you specify
4266 an absolute or relative expiration interval with this parameter, some
4267 browsers and proxy servers will cache the script's output until the
4268 indicated expiration date.  The following forms are all valid for the
4269 -expires field:
4270
4271         +30s                              30 seconds from now
4272         +10m                              ten minutes from now
4273         +1h                               one hour from now
4274         -1d                               yesterday (i.e. "ASAP!")
4275         now                               immediately
4276         +3M                               in three months
4277         +10y                              in ten years time
4278         Thursday, 25-Apr-1999 00:40:33 GMT  at the indicated time & date
4279
4280 The B<-cookie> parameter generates a header that tells the browser to provide
4281 a "magic cookie" during all subsequent transactions with your script.
4282 Netscape cookies have a special format that includes interesting attributes
4283 such as expiration time.  Use the cookie() method to create and retrieve
4284 session cookies.
4285
4286 The B<-nph> parameter, if set to a true value, will issue the correct
4287 headers to work with a NPH (no-parse-header) script.  This is important
4288 to use with certain servers that expect all their scripts to be NPH.
4289
4290 The B<-charset> parameter can be used to control the character set
4291 sent to the browser.  If not provided, defaults to ISO-8859-1.  As a
4292 side effect, this sets the charset() method as well.
4293
4294 The B<-attachment> parameter can be used to turn the page into an
4295 attachment.  Instead of displaying the page, some browsers will prompt
4296 the user to save it to disk.  The value of the argument is the
4297 suggested name for the saved file.  In order for this to work, you may
4298 have to set the B<-type> to "application/octet-stream".
4299
4300 =head2 GENERATING A REDIRECTION HEADER
4301
4302    print $query->redirect('http://somewhere.else/in/movie/land');
4303
4304 Sometimes you don't want to produce a document yourself, but simply
4305 redirect the browser elsewhere, perhaps choosing a URL based on the
4306 time of day or the identity of the user.
4307
4308 The redirect() function redirects the browser to a different URL.  If
4309 you use redirection like this, you should B<not> print out a header as
4310 well.
4311
4312 One hint I can offer is that relative links may not work correctly
4313 when you generate a redirection to another document on your site.
4314 This is due to a well-intentioned optimization that some servers use.
4315 The solution to this is to use the full URL (including the http: part)
4316 of the document you are redirecting to.
4317
4318 You can also use named arguments:
4319
4320     print $query->redirect(-uri=>'http://somewhere.else/in/movie/land',
4321                            -nph=>1);
4322
4323 The B<-nph> parameter, if set to a true value, will issue the correct
4324 headers to work with a NPH (no-parse-header) script.  This is important
4325 to use with certain servers, such as Microsoft Internet Explorer, which
4326 expect all their scripts to be NPH.
4327
4328 =head2 CREATING THE HTML DOCUMENT HEADER
4329
4330    print $query->start_html(-title=>'Secrets of the Pyramids',
4331                             -author=>'fred@capricorn.org',
4332                             -base=>'true',
4333                             -target=>'_blank',
4334                             -meta=>{'keywords'=>'pharaoh secret mummy',
4335                                     'copyright'=>'copyright 1996 King Tut'},
4336                             -style=>{'src'=>'/styles/style1.css'},
4337                             -BGCOLOR=>'blue');
4338
4339 After creating the HTTP header, most CGI scripts will start writing
4340 out an HTML document.  The start_html() routine creates the top of the
4341 page, along with a lot of optional information that controls the
4342 page's appearance and behavior.
4343
4344 This method returns a canned HTML header and the opening <BODY> tag.
4345 All parameters are optional.  In the named parameter form, recognized
4346 parameters are -title, -author, -base, -xbase, -dtd, -lang and -target
4347 (see below for the explanation).  Any additional parameters you
4348 provide, such as the Netscape unofficial BGCOLOR attribute, are added
4349 to the <BODY> tag.  Additional parameters must be proceeded by a
4350 hyphen.
4351
4352 The argument B<-xbase> allows you to provide an HREF for the <BASE> tag
4353 different from the current location, as in
4354
4355     -xbase=>"http://home.mcom.com/"
4356
4357 All relative links will be interpreted relative to this tag.
4358
4359 The argument B<-target> allows you to provide a default target frame
4360 for all the links and fill-out forms on the page.  B<This is a
4361 non-standard HTTP feature which only works with Netscape browsers!>
4362 See the Netscape documentation on frames for details of how to
4363 manipulate this.
4364
4365     -target=>"answer_window"
4366
4367 All relative links will be interpreted relative to this tag.
4368 You add arbitrary meta information to the header with the B<-meta>
4369 argument.  This argument expects a reference to an associative array
4370 containing name/value pairs of meta information.  These will be turned
4371 into a series of header <META> tags that look something like this:
4372
4373     <META NAME="keywords" CONTENT="pharaoh secret mummy">
4374     <META NAME="description" CONTENT="copyright 1996 King Tut">
4375
4376 To create an HTTP-EQUIV type of <META> tag, use B<-head>, described
4377 below.
4378
4379 The B<-style> argument is used to incorporate cascading stylesheets
4380 into your code.  See the section on CASCADING STYLESHEETS for more
4381 information.
4382
4383 The B<-lang> argument is used to incorporate a language attribute into
4384 the <HTML> tag.  The default if not specified is "en-US" for US
4385 English.  For example:
4386
4387     print $q->start_html(-lang=>'fr-CA');
4388
4389 You can place other arbitrary HTML elements to the <HEAD> section with the
4390 B<-head> tag.  For example, to place the rarely-used <LINK> element in the
4391 head section, use this:
4392
4393     print start_html(-head=>Link({-rel=>'next',
4394                                   -href=>'http://www.capricorn.com/s2.html'}));
4395
4396 To incorporate multiple HTML elements into the <HEAD> section, just pass an
4397 array reference:
4398
4399     print start_html(-head=>[
4400                              Link({-rel=>'next',
4401                                    -href=>'http://www.capricorn.com/s2.html'}),
4402                              Link({-rel=>'previous',
4403                                    -href=>'http://www.capricorn.com/s1.html'})
4404                              ]
4405                      );
4406
4407 And here's how to create an HTTP-EQUIV <META> tag:
4408
4409       print start_html(-head=>meta({-http_equiv => 'Content-Type',
4410                                     -content    => 'text/html'}))
4411
4412
4413 JAVASCRIPTING: The B<-script>, B<-noScript>, B<-onLoad>,
4414 B<-onMouseOver>, B<-onMouseOut> and B<-onUnload> parameters are used
4415 to add Netscape JavaScript calls to your pages.  B<-script> should
4416 point to a block of text containing JavaScript function definitions.
4417 This block will be placed within a <SCRIPT> block inside the HTML (not
4418 HTTP) header.  The block is placed in the header in order to give your
4419 page a fighting chance of having all its JavaScript functions in place
4420 even if the user presses the stop button before the page has loaded
4421 completely.  CGI.pm attempts to format the script in such a way that
4422 JavaScript-naive browsers will not choke on the code: unfortunately
4423 there are some browsers, such as Chimera for Unix, that get confused
4424 by it nevertheless.
4425
4426 The B<-onLoad> and B<-onUnload> parameters point to fragments of JavaScript
4427 code to execute when the page is respectively opened and closed by the
4428 browser.  Usually these parameters are calls to functions defined in the
4429 B<-script> field:
4430
4431       $query = new CGI;
4432       print $query->header;
4433       $JSCRIPT=<<END;
4434       // Ask a silly question
4435       function riddle_me_this() {
4436          var r = prompt("What walks on four legs in the morning, " +
4437                        "two legs in the afternoon, " +
4438                        "and three legs in the evening?");
4439          response(r);
4440       }
4441       // Get a silly answer
4442       function response(answer) {
4443          if (answer == "man")
4444             alert("Right you are!");
4445          else
4446             alert("Wrong!  Guess again.");
4447       }
4448       END
4449       print $query->start_html(-title=>'The Riddle of the Sphinx',
4450                                -script=>$JSCRIPT);
4451
4452 Use the B<-noScript> parameter to pass some HTML text that will be displayed on
4453 browsers that do not have JavaScript (or browsers where JavaScript is turned
4454 off).
4455
4456 Netscape 3.0 recognizes several attributes of the <SCRIPT> tag,
4457 including LANGUAGE and SRC.  The latter is particularly interesting,
4458 as it allows you to keep the JavaScript code in a file or CGI script
4459 rather than cluttering up each page with the source.  To use these
4460 attributes pass a HASH reference in the B<-script> parameter containing
4461 one or more of -language, -src, or -code:
4462
4463     print $q->start_html(-title=>'The Riddle of the Sphinx',
4464                          -script=>{-language=>'JAVASCRIPT',
4465                                    -src=>'/javascript/sphinx.js'}
4466                          );
4467
4468     print $q->(-title=>'The Riddle of the Sphinx',
4469                -script=>{-language=>'PERLSCRIPT',
4470                          -code=>'print "hello world!\n;"'}
4471                );
4472
4473
4474 A final feature allows you to incorporate multiple <SCRIPT> sections into the
4475 header.  Just pass the list of script sections as an array reference.
4476 this allows you to specify different source files for different dialects
4477 of JavaScript.  Example:
4478
4479      print $q->start_html(-title=>'The Riddle of the Sphinx',
4480                           -script=>[
4481                                     { -language => 'JavaScript1.0',
4482                                       -src      => '/javascript/utilities10.js'
4483                                     },
4484                                     { -language => 'JavaScript1.1',
4485                                       -src      => '/javascript/utilities11.js'
4486                                     },
4487                                     { -language => 'JavaScript1.2',
4488                                       -src      => '/javascript/utilities12.js'
4489                                     },
4490                                     { -language => 'JavaScript28.2',
4491                                       -src      => '/javascript/utilities219.js'
4492                                     }
4493                                  ]
4494                              );
4495      </pre>
4496
4497 If this looks a bit extreme, take my advice and stick with straight CGI scripting.
4498
4499 See
4500
4501    http://home.netscape.com/eng/mozilla/2.0/handbook/javascript/
4502
4503 for more information about JavaScript.
4504
4505 The old-style positional parameters are as follows:
4506
4507 =over 4
4508
4509 =item B<Parameters:>
4510
4511 =item 1.
4512
4513 The title
4514
4515 =item 2.
4516
4517 The author's e-mail address (will create a <LINK REV="MADE"> tag if present
4518
4519 =item 3.
4520
4521 A 'true' flag if you want to include a <BASE> tag in the header.  This
4522 helps resolve relative addresses to absolute ones when the document is moved,
4523 but makes the document hierarchy non-portable.  Use with care!
4524
4525 =item 4, 5, 6...
4526
4527 Any other parameters you want to include in the <BODY> tag.  This is a good
4528 place to put Netscape extensions, such as colors and wallpaper patterns.
4529
4530 =back
4531
4532 =head2 ENDING THE HTML DOCUMENT:
4533
4534         print $query->end_html
4535
4536 This ends an HTML document by printing the </BODY></HTML> tags.
4537
4538 =head2 CREATING A SELF-REFERENCING URL THAT PRESERVES STATE INFORMATION:
4539
4540     $myself = $query->self_url;
4541     print q(<A HREF="$myself">I'm talking to myself.</A>);
4542
4543 self_url() will return a URL, that, when selected, will reinvoke
4544 this script with all its state information intact.  This is most
4545 useful when you want to jump around within the document using
4546 internal anchors but you don't want to disrupt the current contents
4547 of the form(s).  Something like this will do the trick.
4548
4549      $myself = $query->self_url;
4550      print "<A HREF=$myself#table1>See table 1</A>";
4551      print "<A HREF=$myself#table2>See table 2</A>";
4552      print "<A HREF=$myself#yourself>See for yourself</A>";
4553
4554 If you want more control over what's returned, using the B<url()>
4555 method instead.
4556
4557 You can also retrieve the unprocessed query string with query_string():
4558
4559     $the_string = $query->query_string;
4560
4561 =head2 OBTAINING THE SCRIPT'S URL
4562
4563     $full_url      = $query->url();
4564     $full_url      = $query->url(-full=>1);  #alternative syntax
4565     $relative_url  = $query->url(-relative=>1);
4566     $absolute_url  = $query->url(-absolute=>1);
4567     $url_with_path = $query->url(-path_info=>1);
4568     $url_with_path_and_query = $query->url(-path_info=>1,-query=>1);
4569     $netloc        = $query->url(-base => 1);
4570
4571 B<url()> returns the script's URL in a variety of formats.  Called
4572 without any arguments, it returns the full form of the URL, including
4573 host name and port number
4574
4575     http://your.host.com/path/to/script.cgi
4576
4577 You can modify this format with the following named arguments:
4578
4579 =over 4
4580
4581 =item B<-absolute>
4582
4583 If true, produce an absolute URL, e.g.
4584
4585     /path/to/script.cgi
4586
4587 =item B<-relative>
4588
4589 Produce a relative URL.  This is useful if you want to reinvoke your
4590 script with different parameters. For example:
4591
4592     script.cgi
4593
4594 =item B<-full>
4595
4596 Produce the full URL, exactly as if called without any arguments.
4597 This overrides the -relative and -absolute arguments.
4598
4599 =item B<-path> (B<-path_info>)
4600
4601 Append the additional path information to the URL.  This can be
4602 combined with B<-full>, B<-absolute> or B<-relative>.  B<-path_info>
4603 is provided as a synonym.
4604
4605 =item B<-query> (B<-query_string>)
4606
4607 Append the query string to the URL.  This can be combined with
4608 B<-full>, B<-absolute> or B<-relative>.  B<-query_string> is provided
4609 as a synonym.
4610
4611 =item B<-base>
4612
4613 Generate just the protocol and net location, as in http://www.foo.com:8000
4614
4615 =back
4616
4617 =head2 MIXING POST AND URL PARAMETERS
4618
4619    $color = $query-&gt;url_param('color');
4620
4621 It is possible for a script to receive CGI parameters in the URL as
4622 well as in the fill-out form by creating a form that POSTs to a URL
4623 containing a query string (a "?" mark followed by arguments).  The
4624 B<param()> method will always return the contents of the POSTed
4625 fill-out form, ignoring the URL's query string.  To retrieve URL
4626 parameters, call the B<url_param()> method.  Use it in the same way as
4627 B<param()>.  The main difference is that it allows you to read the
4628 parameters, but not set them.
4629
4630
4631 Under no circumstances will the contents of the URL query string
4632 interfere with similarly-named CGI parameters in POSTed forms.  If you
4633 try to mix a URL query string with a form submitted with the GET
4634 method, the results will not be what you expect.
4635
4636 =head1 CREATING STANDARD HTML ELEMENTS:
4637
4638 CGI.pm defines general HTML shortcut methods for most, if not all of
4639 the HTML 3 and HTML 4 tags.  HTML shortcuts are named after a single
4640 HTML element and return a fragment of HTML text that you can then
4641 print or manipulate as you like.  Each shortcut returns a fragment of
4642 HTML code that you can append to a string, save to a file, or, most
4643 commonly, print out so that it displays in the browser window.
4644
4645 This example shows how to use the HTML methods:
4646
4647    $q = new CGI;
4648    print $q->blockquote(
4649                      "Many years ago on the island of",
4650                      $q->a({href=>"http://crete.org/"},"Crete"),
4651                      "there lived a Minotaur named",
4652                      $q->strong("Fred."),
4653                     ),
4654        $q->hr;
4655
4656 This results in the following HTML code (extra newlines have been
4657 added for readability):
4658
4659    <blockquote>
4660    Many years ago on the island of
4661    <a HREF="http://crete.org/">Crete</a> there lived
4662    a minotaur named <strong>Fred.</strong>
4663    </blockquote>
4664    <hr>
4665
4666 If you find the syntax for calling the HTML shortcuts awkward, you can
4667 import them into your namespace and dispense with the object syntax
4668 completely (see the next section for more details):
4669
4670    use CGI ':standard';
4671    print blockquote(
4672       "Many years ago on the island of",
4673       a({href=>"http://crete.org/"},"Crete"),
4674       "there lived a minotaur named",
4675       strong("Fred."),
4676       ),
4677       hr;
4678
4679 =head2 PROVIDING ARGUMENTS TO HTML SHORTCUTS
4680
4681 The HTML methods will accept zero, one or multiple arguments.  If you
4682 provide no arguments, you get a single tag:
4683
4684    print hr;    #  <HR>
4685
4686 If you provide one or more string arguments, they are concatenated
4687 together with spaces and placed between opening and closing tags:
4688
4689    print h1("Chapter","1"); # <H1>Chapter 1</H1>"
4690
4691 If the first argument is an associative array reference, then the keys
4692 and values of the associative array become the HTML tag's attributes:
4693
4694    print a({-href=>'fred.html',-target=>'_new'},
4695       "Open a new frame");
4696
4697             <A HREF="fred.html",TARGET="_new">Open a new frame</A>
4698
4699 You may dispense with the dashes in front of the attribute names if
4700 you prefer:
4701
4702    print img {src=>'fred.gif',align=>'LEFT'};
4703
4704            <IMG ALIGN="LEFT" SRC="fred.gif">
4705
4706 Sometimes an HTML tag attribute has no argument.  For example, ordered
4707 lists can be marked as COMPACT.  The syntax for this is an argument that
4708 that points to an undef string:
4709
4710    print ol({compact=>undef},li('one'),li('two'),li('three'));
4711
4712 Prior to CGI.pm version 2.41, providing an empty ('') string as an
4713 attribute argument was the same as providing undef.  However, this has
4714 changed in order to accommodate those who want to create tags of the form
4715 <IMG ALT="">.  The difference is shown in these two pieces of code:
4716
4717    CODE                   RESULT
4718    img({alt=>undef})      <IMG ALT>
4719    img({alt=>''})         <IMT ALT="">
4720
4721 =head2 THE DISTRIBUTIVE PROPERTY OF HTML SHORTCUTS
4722
4723 One of the cool features of the HTML shortcuts is that they are
4724 distributive.  If you give them an argument consisting of a
4725 B<reference> to a list, the tag will be distributed across each
4726 element of the list.  For example, here's one way to make an ordered
4727 list:
4728
4729    print ul(
4730              li({-type=>'disc'},['Sneezy','Doc','Sleepy','Happy'])
4731            );
4732
4733 This example will result in HTML output that looks like this:
4734
4735    <UL>
4736      <LI TYPE="disc">Sneezy</LI>
4737      <LI TYPE="disc">Doc</LI>
4738      <LI TYPE="disc">Sleepy</LI>
4739      <LI TYPE="disc">Happy</LI>
4740    </UL>
4741
4742 This is extremely useful for creating tables.  For example:
4743
4744    print table({-border=>undef},
4745            caption('When Should You Eat Your Vegetables?'),
4746            Tr({-align=>CENTER,-valign=>TOP},
4747            [
4748               th(['Vegetable', 'Breakfast','Lunch','Dinner']),
4749               td(['Tomatoes' , 'no', 'yes', 'yes']),
4750               td(['Broccoli' , 'no', 'no',  'yes']),
4751               td(['Onions'   , 'yes','yes', 'yes'])
4752            ]
4753            )
4754         );
4755
4756 =head2 HTML SHORTCUTS AND LIST INTERPOLATION
4757
4758 Consider this bit of code:
4759
4760    print blockquote(em('Hi'),'mom!'));
4761
4762 It will ordinarily return the string that you probably expect, namely:
4763
4764    <BLOCKQUOTE><EM>Hi</EM> mom!</BLOCKQUOTE>
4765
4766 Note the space between the element "Hi" and the element "mom!".
4767 CGI.pm puts the extra space there using array interpolation, which is
4768 controlled by the magic $" variable.  Sometimes this extra space is
4769 not what you want, for example, when you are trying to align a series
4770 of images.  In this case, you can simply change the value of $" to an
4771 empty string.
4772
4773    {
4774       local($") = '';
4775       print blockquote(em('Hi'),'mom!'));
4776     }
4777
4778 I suggest you put the code in a block as shown here.  Otherwise the
4779 change to $" will affect all subsequent code until you explicitly
4780 reset it.
4781
4782 =head2 NON-STANDARD HTML SHORTCUTS
4783
4784 A few HTML tags don't follow the standard pattern for various
4785 reasons.
4786
4787 B<comment()> generates an HTML comment (<!-- comment -->).  Call it
4788 like
4789
4790     print comment('here is my comment');
4791
4792 Because of conflicts with built-in Perl functions, the following functions
4793 begin with initial caps:
4794
4795     Select
4796     Tr
4797     Link
4798     Delete
4799     Accept
4800     Sub
4801
4802 In addition, start_html(), end_html(), start_form(), end_form(),
4803 start_multipart_form() and all the fill-out form tags are special.
4804 See their respective sections.
4805
4806 =head2 AUTOESCAPING HTML
4807
4808 By default, all HTML that is emitted by the form-generating functions
4809 is passed through a function called escapeHTML():
4810
4811 =over 4
4812
4813 =item $escaped_string = escapeHTML("unescaped string");
4814
4815 Escape HTML formatting characters in a string.
4816
4817 =back
4818
4819 Provided that you have specified a character set of ISO-8859-1 (the
4820 default), the standard HTML escaping rules will be used.  The "<"
4821 character becomes "&lt;", ">" becomes "&gt;", "&" becomes "&amp;", and
4822 the quote character becomes "&quot;".  In addition, the hexadecimal
4823 0x8b and 0x9b characters, which many windows-based browsers interpret
4824 as the left and right angle-bracket characters, are replaced by their
4825 numeric HTML entities ("&#139" and "&#155;").  If you manually change
4826 the charset, either by calling the charset() method explicitly or by
4827 passing a -charset argument to header(), then B<all> characters will
4828 be replaced by their numeric entities, since CGI.pm has no lookup
4829 table for all the possible encodings.
4830
4831 The automatic escaping does not apply to other shortcuts, such as
4832 h1().  You should call escapeHTML() yourself on untrusted data in
4833 order to protect your pages against nasty tricks that people may enter
4834 into guestbooks, etc..  To change the character set, use charset().
4835 To turn autoescaping off completely, use autoescape():
4836
4837 =over 4
4838
4839 =item $charset = charset([$charset]);
4840
4841 Get or set the current character set.
4842
4843 =item $flag = autoEscape([$flag]);
4844
4845 Get or set the value of the autoescape flag.
4846
4847 =back
4848
4849 =head2 PRETTY-PRINTING HTML
4850
4851 By default, all the HTML produced by these functions comes out as one
4852 long line without carriage returns or indentation. This is yuck, but
4853 it does reduce the size of the documents by 10-20%.  To get
4854 pretty-printed output, please use L<CGI::Pretty>, a subclass
4855 contributed by Brian Paulsen.
4856
4857 =head1 CREATING FILL-OUT FORMS:
4858
4859 I<General note>  The various form-creating methods all return strings
4860 to the caller, containing the tag or tags that will create the requested
4861 form element.  You are responsible for actually printing out these strings.
4862 It's set up this way so that you can place formatting tags
4863 around the form elements.
4864
4865 I<Another note> The default values that you specify for the forms are only
4866 used the B<first> time the script is invoked (when there is no query
4867 string).  On subsequent invocations of the script (when there is a query
4868 string), the former values are used even if they are blank.
4869
4870 If you want to change the value of a field from its previous value, you have two
4871 choices:
4872
4873 (1) call the param() method to set it.
4874
4875 (2) use the -override (alias -force) parameter (a new feature in version 2.15).
4876 This forces the default value to be used, regardless of the previous value:
4877
4878    print $query->textfield(-name=>'field_name',
4879                            -default=>'starting value',
4880                            -override=>1,
4881                            -size=>50,
4882                            -maxlength=>80);
4883
4884 I<Yet another note> By default, the text and labels of form elements are
4885 escaped according to HTML rules.  This means that you can safely use
4886 "<CLICK ME>" as the label for a button.  However, it also interferes with
4887 your ability to incorporate special HTML character sequences, such as &Aacute;,
4888 into your fields.  If you wish to turn off automatic escaping, call the
4889 autoEscape() method with a false value immediately after creating the CGI object:
4890
4891    $query = new CGI;
4892    $query->autoEscape(undef);
4893
4894 =head2 CREATING AN ISINDEX TAG
4895
4896    print $query->isindex(-action=>$action);
4897
4898          -or-
4899
4900    print $query->isindex($action);
4901
4902 Prints out an <ISINDEX> tag.  Not very exciting.  The parameter
4903 -action specifies the URL of the script to process the query.  The
4904 default is to process the query with the current script.
4905
4906 =head2 STARTING AND ENDING A FORM
4907
4908     print $query->start_form(-method=>$method,
4909                             -action=>$action,
4910                             -enctype=>$encoding);
4911       <... various form stuff ...>
4912     print $query->endform;
4913
4914         -or-
4915
4916     print $query->start_form($method,$action,$encoding);
4917       <... various form stuff ...>
4918     print $query->endform;
4919
4920 start_form() will return a <FORM> tag with the optional method,
4921 action and form encoding that you specify.  The defaults are:
4922
4923     method: POST
4924     action: this script
4925     enctype: application/x-www-form-urlencoded
4926
4927 endform() returns the closing </FORM> tag.
4928
4929 Start_form()'s enctype argument tells the browser how to package the various
4930 fields of the form before sending the form to the server.  Two
4931 values are possible:
4932
4933 B<Note:> This method was previously named startform(), and startform()
4934 is still recognized as an alias.
4935
4936 =over 4
4937
4938 =item B<application/x-www-form-urlencoded>
4939
4940 This is the older type of encoding used by all browsers prior to
4941 Netscape 2.0.  It is compatible with many CGI scripts and is
4942 suitable for short fields containing text data.  For your
4943 convenience, CGI.pm stores the name of this encoding
4944 type in B<&CGI::URL_ENCODED>.
4945
4946 =item B<multipart/form-data>
4947
4948 This is the newer type of encoding introduced by Netscape 2.0.
4949 It is suitable for forms that contain very large fields or that
4950 are intended for transferring binary data.  Most importantly,
4951 it enables the "file upload" feature of Netscape 2.0 forms.  For
4952 your convenience, CGI.pm stores the name of this encoding type
4953 in B<&CGI::MULTIPART>
4954
4955 Forms that use this type of encoding are not easily interpreted
4956 by CGI scripts unless they use CGI.pm or another library designed
4957 to handle them.
4958
4959 =back
4960
4961 For compatibility, the start_form() method uses the older form of
4962 encoding by default.  If you want to use the newer form of encoding
4963 by default, you can call B<start_multipart_form()> instead of
4964 B<start_form()>.
4965
4966 JAVASCRIPTING: The B<-name> and B<-onSubmit> parameters are provided
4967 for use with JavaScript.  The -name parameter gives the
4968 form a name so that it can be identified and manipulated by
4969 JavaScript functions.  -onSubmit should point to a JavaScript
4970 function that will be executed just before the form is submitted to your
4971 server.  You can use this opportunity to check the contents of the form
4972 for consistency and completeness.  If you find something wrong, you
4973 can put up an alert box or maybe fix things up yourself.  You can
4974 abort the submission by returning false from this function.
4975
4976 Usually the bulk of JavaScript functions are defined in a <SCRIPT>
4977 block in the HTML header and -onSubmit points to one of these function
4978 call.  See start_html() for details.
4979
4980 =head2 CREATING A TEXT FIELD
4981
4982     print $query->textfield(-name=>'field_name',
4983                             -default=>'starting value',
4984                             -size=>50,
4985                             -maxlength=>80);
4986         -or-
4987
4988     print $query->textfield('field_name','starting value',50,80);
4989
4990 textfield() will return a text input field.
4991
4992 =over 4
4993
4994 =item B<Parameters>
4995
4996 =item 1.
4997
4998 The first parameter is the required name for the field (-name).
4999
5000 =item 2.
5001
5002 The optional second parameter is the default starting value for the field
5003 contents (-default).
5004
5005 =item 3.
5006
5007 The optional third parameter is the size of the field in
5008       characters (-size).
5009
5010 =item 4.
5011
5012 The optional fourth parameter is the maximum number of characters the
5013       field will accept (-maxlength).
5014
5015 =back
5016
5017 As with all these methods, the field will be initialized with its
5018 previous contents from earlier invocations of the script.
5019 When the form is processed, the value of the text field can be
5020 retrieved with:
5021
5022        $value = $query->param('foo');
5023
5024 If you want to reset it from its initial value after the script has been
5025 called once, you can do so like this:
5026
5027        $query->param('foo',"I'm taking over this value!");
5028
5029 NEW AS OF VERSION 2.15: If you don't want the field to take on its previous
5030 value, you can force its current value by using the -override (alias -force)
5031 parameter:
5032
5033     print $query->textfield(-name=>'field_name',
5034                             -default=>'starting value',
5035                             -override=>1,
5036                             -size=>50,
5037                             -maxlength=>80);
5038
5039 JAVASCRIPTING: You can also provide B<-onChange>, B<-onFocus>,
5040 B<-onBlur>, B<-onMouseOver>, B<-onMouseOut> and B<-onSelect>
5041 parameters to register JavaScript event handlers.  The onChange
5042 handler will be called whenever the user changes the contents of the
5043 text field.  You can do text validation if you like.  onFocus and
5044 onBlur are called respectively when the insertion point moves into and
5045 out of the text field.  onSelect is called when the user changes the
5046 portion of the text that is selected.
5047
5048 =head2 CREATING A BIG TEXT FIELD
5049
5050    print $query->textarea(-name=>'foo',
5051                           -default=>'starting value',
5052                           -rows=>10,
5053                           -columns=>50);
5054
5055         -or
5056
5057    print $query->textarea('foo','starting value',10,50);
5058
5059 textarea() is just like textfield, but it allows you to specify
5060 rows and columns for a multiline text entry box.  You can provide
5061 a starting value for the field, which can be long and contain
5062 multiple lines.
5063
5064 JAVASCRIPTING: The B<-onChange>, B<-onFocus>, B<-onBlur> ,
5065 B<-onMouseOver>, B<-onMouseOut>, and B<-onSelect> parameters are
5066 recognized.  See textfield().
5067
5068 =head2 CREATING A PASSWORD FIELD
5069
5070    print $query->password_field(-name=>'secret',
5071                                 -value=>'starting value',
5072                                 -size=>50,
5073                                 -maxlength=>80);
5074         -or-
5075
5076    print $query->password_field('secret','starting value',50,80);
5077
5078 password_field() is identical to textfield(), except that its contents
5079 will be starred out on the web page.
5080
5081 JAVASCRIPTING: The B<-onChange>, B<-onFocus>, B<-onBlur>,
5082 B<-onMouseOver>, B<-onMouseOut> and B<-onSelect> parameters are
5083 recognized.  See textfield().
5084
5085 =head2 CREATING A FILE UPLOAD FIELD
5086
5087     print $query->filefield(-name=>'uploaded_file',
5088                             -default=>'starting value',
5089                             -size=>50,
5090                             -maxlength=>80);
5091         -or-
5092
5093     print $query->filefield('uploaded_file','starting value',50,80);
5094
5095 filefield() will return a file upload field for Netscape 2.0 browsers.
5096 In order to take full advantage of this I<you must use the new
5097 multipart encoding scheme> for the form.  You can do this either
5098 by calling B<start_form()> with an encoding type of B<&CGI::MULTIPART>,
5099 or by calling the new method B<start_multipart_form()> instead of
5100 vanilla B<start_form()>.
5101
5102 =over 4
5103
5104 =item B<Parameters>
5105
5106 =item 1.
5107
5108 The first parameter is the required name for the field (-name).
5109
5110 =item 2.
5111
5112 The optional second parameter is the starting value for the field contents
5113 to be used as the default file name (-default).
5114
5115 For security reasons, browsers don't pay any attention to this field,
5116 and so the starting value will always be blank.  Worse, the field
5117 loses its "sticky" behavior and forgets its previous contents.  The
5118 starting value field is called for in the HTML specification, however,
5119 and possibly some browser will eventually provide support for it.
5120
5121 =item 3.
5122
5123 The optional third parameter is the size of the field in
5124 characters (-size).
5125
5126 =item 4.
5127
5128 The optional fourth parameter is the maximum number of characters the
5129 field will accept (-maxlength).
5130
5131 =back
5132
5133 When the form is processed, you can retrieve the entered filename
5134 by calling param():
5135
5136        $filename = $query->param('uploaded_file');
5137
5138 Different browsers will return slightly different things for the
5139 name.  Some browsers return the filename only.  Others return the full
5140 path to the file, using the path conventions of the user's machine.
5141 Regardless, the name returned is always the name of the file on the
5142 I<user's> machine, and is unrelated to the name of the temporary file
5143 that CGI.pm creates during upload spooling (see below).
5144
5145 The filename returned is also a file handle.  You can read the contents
5146 of the file using standard Perl file reading calls:
5147
5148         # Read a text file and print it out
5149         while (<$filename>) {
5150            print;
5151         }
5152
5153         # Copy a binary file to somewhere safe
5154         open (OUTFILE,">>/usr/local/web/users/feedback");
5155         while ($bytesread=read($filename,$buffer,1024)) {
5156            print OUTFILE $buffer;
5157         }
5158
5159 However, there are problems with the dual nature of the upload fields.
5160 If you C<use strict>, then Perl will complain when you try to use a
5161 string as a filehandle.  You can get around this by placing the file
5162 reading code in a block containing the C<no strict> pragma.  More
5163 seriously, it is possible for the remote user to type garbage into the
5164 upload field, in which case what you get from param() is not a
5165 filehandle at all, but a string.
5166
5167 To be safe, use the I<upload()> function (new in version 2.47).  When
5168 called with the name of an upload field, I<upload()> returns a
5169 filehandle, or undef if the parameter is not a valid filehandle.
5170
5171      $fh = $query->upload('uploaded_file');
5172      while (<$fh>) {
5173            print;
5174      }
5175
5176 This is the recommended idiom.
5177
5178 When a file is uploaded the browser usually sends along some
5179 information along with it in the format of headers.  The information
5180 usually includes the MIME content type.  Future browsers may send
5181 other information as well (such as modification date and size). To
5182 retrieve this information, call uploadInfo().  It returns a reference to
5183 an associative array containing all the document headers.
5184
5185        $filename = $query->param('uploaded_file');
5186        $type = $query->uploadInfo($filename)->{'Content-Type'};
5187        unless ($type eq 'text/html') {
5188           die "HTML FILES ONLY!";
5189        }
5190
5191 If you are using a machine that recognizes "text" and "binary" data
5192 modes, be sure to understand when and how to use them (see the Camel book).
5193 Otherwise you may find that binary files are corrupted during file
5194 uploads.
5195
5196 There are occasionally problems involving parsing the uploaded file.
5197 This usually happens when the user presses "Stop" before the upload is
5198 finished.  In this case, CGI.pm will return undef for the name of the
5199 uploaded file and set I<cgi_error()> to the string "400 Bad request
5200 (malformed multipart POST)".  This error message is designed so that
5201 you can incorporate it into a status code to be sent to the browser.
5202 Example:
5203
5204    $file = $query->upload('uploaded_file');
5205    if (!$file && $query->cgi_error) {
5206       print $query->header(-status=>$query->cgi_error);
5207       exit 0;
5208    }
5209
5210 You are free to create a custom HTML page to complain about the error,
5211 if you wish.
5212
5213 JAVASCRIPTING: The B<-onChange>, B<-onFocus>, B<-onBlur>,
5214 B<-onMouseOver>, B<-onMouseOut> and B<-onSelect> parameters are
5215 recognized.  See textfield() for details.
5216
5217 =head2 CREATING A POPUP MENU
5218
5219    print $query->popup_menu('menu_name',
5220                             ['eenie','meenie','minie'],
5221                             'meenie');
5222
5223       -or-
5224
5225    %labels = ('eenie'=>'your first choice',
5226               'meenie'=>'your second choice',
5227               'minie'=>'your third choice');
5228    print $query->popup_menu('menu_name',
5229                             ['eenie','meenie','minie'],
5230                             'meenie',\%labels);
5231
5232         -or (named parameter style)-
5233
5234    print $query->popup_menu(-name=>'menu_name',
5235                             -values=>['eenie','meenie','minie'],
5236                             -default=>'meenie',
5237                             -labels=>\%labels);
5238
5239 popup_menu() creates a menu.
5240
5241 =over 4
5242
5243 =item 1.
5244
5245 The required first argument is the menu's name (-name).
5246
5247 =item 2.
5248
5249 The required second argument (-values) is an array B<reference>
5250 containing the list of menu items in the menu.  You can pass the
5251 method an anonymous array, as shown in the example, or a reference to
5252 a named array, such as "\@foo".
5253
5254 =item 3.
5255
5256 The optional third parameter (-default) is the name of the default
5257 menu choice.  If not specified, the first item will be the default.
5258 The values of the previous choice will be maintained across queries.
5259
5260 =item 4.
5261
5262 The optional fourth parameter (-labels) is provided for people who
5263 want to use different values for the user-visible label inside the
5264 popup menu nd the value returned to your script.  It's a pointer to an
5265 associative array relating menu values to user-visible labels.  If you
5266 leave this parameter blank, the menu values will be displayed by
5267 default.  (You can also leave a label undefined if you want to).
5268
5269 =back
5270
5271 When the form is processed, the selected value of the popup menu can
5272 be retrieved using:
5273
5274       $popup_menu_value = $query->param('menu_name');
5275
5276 JAVASCRIPTING: popup_menu() recognizes the following event handlers:
5277 B<-onChange>, B<-onFocus>, B<-onMouseOver>, B<-onMouseOut>, and
5278 B<-onBlur>.  See the textfield() section for details on when these
5279 handlers are called.
5280
5281 =head2 CREATING A SCROLLING LIST
5282
5283    print $query->scrolling_list('list_name',
5284                                 ['eenie','meenie','minie','moe'],
5285                                 ['eenie','moe'],5,'true');
5286       -or-
5287
5288    print $query->scrolling_list('list_name',
5289                                 ['eenie','meenie','minie','moe'],
5290                                 ['eenie','moe'],5,'true',
5291                                 \%labels);
5292
5293         -or-
5294
5295    print $query->scrolling_list(-name=>'list_name',
5296                                 -values=>['eenie','meenie','minie','moe'],
5297                                 -default=>['eenie','moe'],
5298                                 -size=>5,
5299                                 -multiple=>'true',
5300                                 -labels=>\%labels);
5301
5302 scrolling_list() creates a scrolling list.
5303
5304 =over 4
5305
5306 =item B<Parameters:>
5307
5308 =item 1.
5309
5310 The first and second arguments are the list name (-name) and values
5311 (-values).  As in the popup menu, the second argument should be an
5312 array reference.
5313
5314 =item 2.
5315
5316 The optional third argument (-default) can be either a reference to a
5317 list containing the values to be selected by default, or can be a
5318 single value to select.  If this argument is missing or undefined,
5319 then nothing is selected when the list first appears.  In the named
5320 parameter version, you can use the synonym "-defaults" for this
5321 parameter.
5322
5323 =item 3.
5324
5325 The optional fourth argument is the size of the list (-size).
5326
5327 =item 4.
5328
5329 The optional fifth argument can be set to true to allow multiple
5330 simultaneous selections (-multiple).  Otherwise only one selection
5331 will be allowed at a time.
5332
5333 =item 5.
5334
5335 The optional sixth argument is a pointer to an associative array
5336 containing long user-visible labels for the list items (-labels).
5337 If not provided, the values will be displayed.
5338
5339 When this form is processed, all selected list items will be returned as
5340 a list under the parameter name 'list_name'.  The values of the
5341 selected items can be retrieved with:
5342
5343       @selected = $query->param('list_name');
5344
5345 =back
5346
5347 JAVASCRIPTING: scrolling_list() recognizes the following event
5348 handlers: B<-onChange>, B<-onFocus>, B<-onMouseOver>, B<-onMouseOut>
5349 and B<-onBlur>.  See textfield() for the description of when these
5350 handlers are called.
5351
5352 =head2 CREATING A GROUP OF RELATED CHECKBOXES
5353
5354    print $query->checkbox_group(-name=>'group_name',
5355                                 -values=>['eenie','meenie','minie','moe'],
5356                                 -default=>['eenie','moe'],
5357                                 -linebreak=>'true',
5358                                 -labels=>\%labels);
5359
5360    print $query->checkbox_group('group_name',
5361                                 ['eenie','meenie','minie','moe'],
5362                                 ['eenie','moe'],'true',\%labels);
5363
5364    HTML3-COMPATIBLE BROWSERS ONLY:
5365
5366    print $query->checkbox_group(-name=>'group_name',
5367                                 -values=>['eenie','meenie','minie','moe'],
5368                                 -rows=2,-columns=>2);
5369
5370
5371 checkbox_group() creates a list of checkboxes that are related
5372 by the same name.
5373
5374 =over 4
5375
5376 =item B<Parameters:>
5377
5378 =item 1.
5379
5380 The first and second arguments are the checkbox name and values,
5381 respectively (-name and -values).  As in the popup menu, the second
5382 argument should be an array reference.  These values are used for the
5383 user-readable labels printed next to the checkboxes as well as for the
5384 values passed to your script in the query string.
5385
5386 =item 2.
5387
5388 The optional third argument (-default) can be either a reference to a
5389 list containing the values to be checked by default, or can be a
5390 single value to checked.  If this argument is missing or undefined,
5391 then nothing is selected when the list first appears.
5392
5393 =item 3.
5394
5395 The optional fourth argument (-linebreak) can be set to true to place
5396 line breaks between the checkboxes so that they appear as a vertical
5397 list.  Otherwise, they will be strung together on a horizontal line.
5398
5399 =item 4.
5400
5401 The optional fifth argument is a pointer to an associative array
5402 relating the checkbox values to the user-visible labels that will
5403 be printed next to them (-labels).  If not provided, the values will
5404 be used as the default.
5405
5406 =item 5.
5407
5408 B<HTML3-compatible browsers> (such as Netscape) can take advantage of
5409 the optional parameters B<-rows>, and B<-columns>.  These parameters
5410 cause checkbox_group() to return an HTML3 compatible table containing
5411 the checkbox group formatted with the specified number of rows and
5412 columns.  You can provide just the -columns parameter if you wish;
5413 checkbox_group will calculate the correct number of rows for you.
5414
5415 To include row and column headings in the returned table, you
5416 can use the B<-rowheaders> and B<-colheaders> parameters.  Both
5417 of these accept a pointer to an array of headings to use.
5418 The headings are just decorative.  They don't reorganize the
5419 interpretation of the checkboxes -- they're still a single named
5420 unit.
5421
5422 =back
5423
5424 When the form is processed, all checked boxes will be returned as
5425 a list under the parameter name 'group_name'.  The values of the
5426 "on" checkboxes can be retrieved with:
5427
5428       @turned_on = $query->param('group_name');
5429
5430 The value returned by checkbox_group() is actually an array of button
5431 elements.  You can capture them and use them within tables, lists,
5432 or in other creative ways:
5433
5434     @h = $query->checkbox_group(-name=>'group_name',-values=>\@values);
5435     &use_in_creative_way(@h);
5436
5437 JAVASCRIPTING: checkbox_group() recognizes the B<-onClick>
5438 parameter.  This specifies a JavaScript code fragment or
5439 function call to be executed every time the user clicks on
5440 any of the buttons in the group.  You can retrieve the identity
5441 of the particular button clicked on using the "this" variable.
5442
5443 =head2 CREATING A STANDALONE CHECKBOX
5444
5445     print $query->checkbox(-name=>'checkbox_name',
5446                            -checked=>'checked',
5447                            -value=>'ON',
5448                            -label=>'CLICK ME');
5449
5450         -or-
5451
5452     print $query->checkbox('checkbox_name','checked','ON','CLICK ME');
5453
5454 checkbox() is used to create an isolated checkbox that isn't logically
5455 related to any others.
5456
5457 =over 4
5458
5459 =item B<Parameters:>
5460
5461 =item 1.
5462
5463 The first parameter is the required name for the checkbox (-name).  It
5464 will also be used for the user-readable label printed next to the
5465 checkbox.
5466
5467 =item 2.
5468
5469 The optional second parameter (-checked) specifies that the checkbox
5470 is turned on by default.  Synonyms are -selected and -on.
5471
5472 =item 3.
5473
5474 The optional third parameter (-value) specifies the value of the
5475 checkbox when it is checked.  If not provided, the word "on" is
5476 assumed.
5477
5478 =item 4.
5479
5480 The optional fourth parameter (-label) is the user-readable label to
5481 be attached to the checkbox.  If not provided, the checkbox name is
5482 used.
5483
5484 =back
5485
5486 The value of the checkbox can be retrieved using:
5487
5488     $turned_on = $query->param('checkbox_name');
5489
5490 JAVASCRIPTING: checkbox() recognizes the B<-onClick>
5491 parameter.  See checkbox_group() for further details.
5492
5493 =head2 CREATING A RADIO BUTTON GROUP
5494
5495    print $query->radio_group(-name=>'group_name',
5496                              -values=>['eenie','meenie','minie'],
5497                              -default=>'meenie',
5498                              -linebreak=>'true',
5499                              -labels=>\%labels);
5500
5501         -or-
5502
5503    print $query->radio_group('group_name',['eenie','meenie','minie'],
5504                                           'meenie','true',\%labels);
5505
5506
5507    HTML3-COMPATIBLE BROWSERS ONLY:
5508
5509    print $query->radio_group(-name=>'group_name',
5510                              -values=>['eenie','meenie','minie','moe'],
5511                              -rows=2,-columns=>2);
5512
5513 radio_group() creates a set of logically-related radio buttons
5514 (turning one member of the group on turns the others off)
5515
5516 =over 4
5517
5518 =item B<Parameters:>
5519
5520 =item 1.
5521
5522 The first argument is the name of the group and is required (-name).
5523
5524 =item 2.
5525
5526 The second argument (-values) is the list of values for the radio
5527 buttons.  The values and the labels that appear on the page are
5528 identical.  Pass an array I<reference> in the second argument, either
5529 using an anonymous array, as shown, or by referencing a named array as
5530 in "\@foo".
5531
5532 =item 3.
5533
5534 The optional third parameter (-default) is the name of the default
5535 button to turn on. If not specified, the first item will be the
5536 default.  You can provide a nonexistent button name, such as "-" to
5537 start up with no buttons selected.
5538
5539 =item 4.
5540
5541 The optional fourth parameter (-linebreak) can be set to 'true' to put
5542 line breaks between the buttons, creating a vertical list.
5543
5544 =item 5.
5545
5546 The optional fifth parameter (-labels) is a pointer to an associative
5547 array relating the radio button values to user-visible labels to be
5548 used in the display.  If not provided, the values themselves are
5549 displayed.
5550
5551 =item 6.
5552
5553 B<HTML3-compatible browsers> (such as Netscape) can take advantage
5554 of the optional
5555 parameters B<-rows>, and B<-columns>.  These parameters cause
5556 radio_group() to return an HTML3 compatible table containing
5557 the radio group formatted with the specified number of rows
5558 and columns.  You can provide just the -columns parameter if you
5559 wish; radio_group will calculate the correct number of rows
5560 for you.
5561
5562 To include row and column headings in the returned table, you
5563 can use the B<-rowheader> and B<-colheader> parameters.  Both
5564 of these accept a pointer to an array of headings to use.
5565 The headings are just decorative.  They don't reorganize the
5566 interpretation of the radio buttons -- they're still a single named
5567 unit.
5568
5569 =back
5570
5571 When the form is processed, the selected radio button can
5572 be retrieved using:
5573
5574       $which_radio_button = $query->param('group_name');
5575
5576 The value returned by radio_group() is actually an array of button
5577 elements.  You can capture them and use them within tables, lists,
5578 or in other creative ways:
5579
5580     @h = $query->radio_group(-name=>'group_name',-values=>\@values);
5581     &use_in_creative_way(@h);
5582
5583 =head2 CREATING A SUBMIT BUTTON
5584
5585    print $query->submit(-name=>'button_name',
5586                         -value=>'value');
5587
5588         -or-
5589
5590    print $query->submit('button_name','value');
5591
5592 submit() will create the query submission button.  Every form
5593 should have one of these.
5594
5595 =over 4
5596
5597 =item B<Parameters:>
5598
5599 =item 1.
5600
5601 The first argument (-name) is optional.  You can give the button a
5602 name if you have several submission buttons in your form and you want
5603 to distinguish between them.  The name will also be used as the
5604 user-visible label.  Be aware that a few older browsers don't deal with this correctly and
5605 B<never> send back a value from a button.
5606
5607 =item 2.
5608
5609 The second argument (-value) is also optional.  This gives the button
5610 a value that will be passed to your script in the query string.
5611
5612 =back
5613
5614 You can figure out which button was pressed by using different
5615 values for each one:
5616
5617      $which_one = $query->param('button_name');
5618
5619 JAVASCRIPTING: radio_group() recognizes the B<-onClick>
5620 parameter.  See checkbox_group() for further details.
5621
5622 =head2 CREATING A RESET BUTTON
5623
5624    print $query->reset
5625
5626 reset() creates the "reset" button.  Note that it restores the
5627 form to its value from the last time the script was called,
5628 NOT necessarily to the defaults.
5629
5630 Note that this conflicts with the Perl reset() built-in.  Use
5631 CORE::reset() to get the original reset function.
5632
5633 =head2 CREATING A DEFAULT BUTTON
5634
5635    print $query->defaults('button_label')
5636
5637 defaults() creates a button that, when invoked, will cause the
5638 form to be completely reset to its defaults, wiping out all the
5639 changes the user ever made.
5640
5641 =head2 CREATING A HIDDEN FIELD
5642
5643         print $query->hidden(-name=>'hidden_name',
5644                              -default=>['value1','value2'...]);
5645
5646                 -or-
5647
5648         print $query->hidden('hidden_name','value1','value2'...);
5649
5650 hidden() produces a text field that can't be seen by the user.  It
5651 is useful for passing state variable information from one invocation
5652 of the script to the next.
5653
5654 =over 4
5655
5656 =item B<Parameters:>
5657
5658 =item 1.
5659
5660 The first argument is required and specifies the name of this
5661 field (-name).
5662
5663 =item 2.
5664
5665 The second argument is also required and specifies its value
5666 (-default).  In the named parameter style of calling, you can provide
5667 a single value here or a reference to a whole list
5668
5669 =back
5670
5671 Fetch the value of a hidden field this way:
5672
5673      $hidden_value = $query->param('hidden_name');
5674
5675 Note, that just like all the other form elements, the value of a
5676 hidden field is "sticky".  If you want to replace a hidden field with
5677 some other values after the script has been called once you'll have to
5678 do it manually:
5679
5680      $query->param('hidden_name','new','values','here');
5681
5682 =head2 CREATING A CLICKABLE IMAGE BUTTON
5683
5684      print $query->image_button(-name=>'button_name',
5685                                 -src=>'/source/URL',
5686                                 -align=>'MIDDLE');
5687
5688         -or-
5689
5690      print $query->image_button('button_name','/source/URL','MIDDLE');
5691
5692 image_button() produces a clickable image.  When it's clicked on the
5693 position of the click is returned to your script as "button_name.x"
5694 and "button_name.y", where "button_name" is the name you've assigned
5695 to it.
5696
5697 JAVASCRIPTING: image_button() recognizes the B<-onClick>
5698 parameter.  See checkbox_group() for further details.
5699
5700 =over 4
5701
5702 =item B<Parameters:>
5703
5704 =item 1.
5705
5706 The first argument (-name) is required and specifies the name of this
5707 field.
5708
5709 =item 2.
5710
5711 The second argument (-src) is also required and specifies the URL
5712
5713 =item 3.
5714
5715 The third option (-align, optional) is an alignment type, and may be
5716 TOP, BOTTOM or MIDDLE
5717
5718 =back
5719
5720 Fetch the value of the button this way:
5721      $x = $query->param('button_name.x');
5722      $y = $query->param('button_name.y');
5723
5724 =head2 CREATING A JAVASCRIPT ACTION BUTTON
5725
5726      print $query->button(-name=>'button_name',
5727                           -value=>'user visible label',
5728                           -onClick=>"do_something()");
5729
5730         -or-
5731
5732      print $query->button('button_name',"do_something()");
5733
5734 button() produces a button that is compatible with Netscape 2.0's
5735 JavaScript.  When it's pressed the fragment of JavaScript code
5736 pointed to by the B<-onClick> parameter will be executed.  On
5737 non-Netscape browsers this form element will probably not even
5738 display.
5739
5740 =head1 HTTP COOKIES
5741
5742 Netscape browsers versions 1.1 and higher, and all versions of
5743 Internet Explorer, support a so-called "cookie" designed to help
5744 maintain state within a browser session.  CGI.pm has several methods
5745 that support cookies.
5746
5747 A cookie is a name=value pair much like the named parameters in a CGI
5748 query string.  CGI scripts create one or more cookies and send
5749 them to the browser in the HTTP header.  The browser maintains a list
5750 of cookies that belong to a particular Web server, and returns them
5751 to the CGI script during subsequent interactions.
5752
5753 In addition to the required name=value pair, each cookie has several
5754 optional attributes:
5755
5756 =over 4
5757
5758 =item 1. an expiration time
5759
5760 This is a time/date string (in a special GMT format) that indicates
5761 when a cookie expires.  The cookie will be saved and returned to your
5762 script until this expiration date is reached if the user exits
5763 the browser and restarts it.  If an expiration date isn't specified, the cookie
5764 will remain active until the user quits the browser.
5765
5766 =item 2. a domain
5767
5768 This is a partial or complete domain name for which the cookie is
5769 valid.  The browser will return the cookie to any host that matches
5770 the partial domain name.  For example, if you specify a domain name
5771 of ".capricorn.com", then the browser will return the cookie to
5772 Web servers running on any of the machines "www.capricorn.com",
5773 "www2.capricorn.com", "feckless.capricorn.com", etc.  Domain names
5774 must contain at least two periods to prevent attempts to match
5775 on top level domains like ".edu".  If no domain is specified, then
5776 the browser will only return the cookie to servers on the host the
5777 cookie originated from.
5778
5779 =item 3. a path
5780
5781 If you provide a cookie path attribute, the browser will check it
5782 against your script's URL before returning the cookie.  For example,
5783 if you specify the path "/cgi-bin", then the cookie will be returned
5784 to each of the scripts "/cgi-bin/tally.pl", "/cgi-bin/order.pl",
5785 and "/cgi-bin/customer_service/complain.pl", but not to the script
5786 "/cgi-private/site_admin.pl".  By default, path is set to "/", which
5787 causes the cookie to be sent to any CGI script on your site.
5788
5789 =item 4. a "secure" flag
5790
5791 If the "secure" attribute is set, the cookie will only be sent to your
5792 script if the CGI request is occurring on a secure channel, such as SSL.
5793
5794 =back
5795
5796 The interface to HTTP cookies is the B<cookie()> method:
5797
5798     $cookie = $query->cookie(-name=>'sessionID',
5799                              -value=>'xyzzy',
5800                              -expires=>'+1h',
5801                              -path=>'/cgi-bin/database',
5802                              -domain=>'.capricorn.org',
5803                              -secure=>1);
5804     print $query->header(-cookie=>$cookie);
5805
5806 B<cookie()> creates a new cookie.  Its parameters include:
5807
5808 =over 4
5809
5810 =item B<-name>
5811
5812 The name of the cookie (required).  This can be any string at all.
5813 Although browsers limit their cookie names to non-whitespace
5814 alphanumeric characters, CGI.pm removes this restriction by escaping
5815 and unescaping cookies behind the scenes.
5816
5817 =item B<-value>
5818
5819 The value of the cookie.  This can be any scalar value,
5820 array reference, or even associative array reference.  For example,
5821 you can store an entire associative array into a cookie this way:
5822
5823         $cookie=$query->cookie(-name=>'family information',
5824                                -value=>\%childrens_ages);
5825
5826 =item B<-path>
5827
5828 The optional partial path for which this cookie will be valid, as described
5829 above.
5830
5831 =item B<-domain>
5832
5833 The optional partial domain for which this cookie will be valid, as described
5834 above.
5835
5836 =item B<-expires>
5837
5838 The optional expiration date for this cookie.  The format is as described
5839 in the section on the B<header()> method:
5840
5841         "+1h"  one hour from now
5842
5843 =item B<-secure>
5844
5845 If set to true, this cookie will only be used within a secure
5846 SSL session.
5847
5848 =back
5849
5850 The cookie created by cookie() must be incorporated into the HTTP
5851 header within the string returned by the header() method:
5852
5853         print $query->header(-cookie=>$my_cookie);
5854
5855 To create multiple cookies, give header() an array reference:
5856
5857         $cookie1 = $query->cookie(-name=>'riddle_name',
5858                                   -value=>"The Sphynx's Question");
5859         $cookie2 = $query->cookie(-name=>'answers',
5860                                   -value=>\%answers);
5861         print $query->header(-cookie=>[$cookie1,$cookie2]);
5862
5863 To retrieve a cookie, request it by name by calling cookie() method
5864 without the B<-value> parameter:
5865
5866         use CGI;
5867         $query = new CGI;
5868         $riddle = $query->cookie('riddle_name');
5869         %answers = $query->cookie('answers');
5870
5871 Cookies created with a single scalar value, such as the "riddle_name"
5872 cookie, will be returned in that form.  Cookies with array and hash
5873 values can also be retrieved.
5874
5875 The cookie and CGI namespaces are separate.  If you have a parameter
5876 named 'answers' and a cookie named 'answers', the values retrieved by
5877 param() and cookie() are independent of each other.  However, it's
5878 simple to turn a CGI parameter into a cookie, and vice-versa:
5879
5880    # turn a CGI parameter into a cookie
5881    $c=$q->cookie(-name=>'answers',-value=>[$q->param('answers')]);
5882    # vice-versa
5883    $q->param(-name=>'answers',-value=>[$q->cookie('answers')]);
5884
5885 See the B<cookie.cgi> example script for some ideas on how to use
5886 cookies effectively.
5887
5888 =head1 WORKING WITH FRAMES
5889
5890 It's possible for CGI.pm scripts to write into several browser panels
5891 and windows using the HTML 4 frame mechanism.  There are three
5892 techniques for defining new frames programmatically:
5893
5894 =over 4
5895
5896 =item 1. Create a <Frameset> document
5897
5898 After writing out the HTTP header, instead of creating a standard
5899 HTML document using the start_html() call, create a <FRAMESET>
5900 document that defines the frames on the page.  Specify your script(s)
5901 (with appropriate parameters) as the SRC for each of the frames.
5902
5903 There is no specific support for creating <FRAMESET> sections
5904 in CGI.pm, but the HTML is very simple to write.  See the frame
5905 documentation in Netscape's home pages for details
5906
5907   http://home.netscape.com/assist/net_sites/frames.html
5908
5909 =item 2. Specify the destination for the document in the HTTP header
5910
5911 You may provide a B<-target> parameter to the header() method:
5912
5913     print $q->header(-target=>'ResultsWindow');
5914
5915 This will tell the browser to load the output of your script into the
5916 frame named "ResultsWindow".  If a frame of that name doesn't already
5917 exist, the browser will pop up a new window and load your script's
5918 document into that.  There are a number of magic names that you can
5919 use for targets.  See the frame documents on Netscape's home pages for
5920 details.
5921
5922 =item 3. Specify the destination for the document in the <FORM> tag
5923
5924 You can specify the frame to load in the FORM tag itself.  With
5925 CGI.pm it looks like this:
5926
5927     print $q->start_form(-target=>'ResultsWindow');
5928
5929 When your script is reinvoked by the form, its output will be loaded
5930 into the frame named "ResultsWindow".  If one doesn't already exist
5931 a new window will be created.
5932
5933 =back
5934
5935 The script "frameset.cgi" in the examples directory shows one way to
5936 create pages in which the fill-out form and the response live in
5937 side-by-side frames.
5938
5939 =head1 LIMITED SUPPORT FOR CASCADING STYLE SHEETS
5940
5941 CGI.pm has limited support for HTML3's cascading style sheets (css).
5942 To incorporate a stylesheet into your document, pass the
5943 start_html() method a B<-style> parameter.  The value of this
5944 parameter may be a scalar, in which case it is incorporated directly
5945 into a <STYLE> section, or it may be a hash reference.  In the latter
5946 case you should provide the hash with one or more of B<-src> or
5947 B<-code>.  B<-src> points to a URL where an externally-defined
5948 stylesheet can be found.  B<-code> points to a scalar value to be
5949 incorporated into a <STYLE> section.  Style definitions in B<-code>
5950 override similarly-named ones in B<-src>, hence the name "cascading."
5951
5952 You may also specify the type of the stylesheet by adding the optional
5953 B<-type> parameter to the hash pointed to by B<-style>.  If not
5954 specified, the style defaults to 'text/css'.
5955
5956 To refer to a style within the body of your document, add the
5957 B<-class> parameter to any HTML element:
5958
5959     print h1({-class=>'Fancy'},'Welcome to the Party');
5960
5961 Or define styles on the fly with the B<-style> parameter:
5962
5963     print h1({-style=>'Color: red;'},'Welcome to Hell');
5964
5965 You may also use the new B<span()> element to apply a style to a
5966 section of text:
5967
5968     print span({-style=>'Color: red;'},
5969                h1('Welcome to Hell'),
5970                "Where did that handbasket get to?"
5971                );
5972
5973 Note that you must import the ":html3" definitions to have the
5974 B<span()> method available.  Here's a quick and dirty example of using
5975 CSS's.  See the CSS specification at
5976 http://www.w3.org/pub/WWW/TR/Wd-css-1.html for more information.
5977
5978     use CGI qw/:standard :html3/;
5979
5980     #here's a stylesheet incorporated directly into the page
5981     $newStyle=<<END;
5982     <!--
5983     P.Tip {
5984         margin-right: 50pt;
5985         margin-left: 50pt;
5986         color: red;
5987     }
5988     P.Alert {
5989         font-size: 30pt;
5990         font-family: sans-serif;
5991       color: red;
5992     }
5993     -->
5994     END
5995     print header();
5996     print start_html( -title=>'CGI with Style',
5997                       -style=>{-src=>'http://www.capricorn.com/style/st1.css',
5998                                -code=>$newStyle}
5999                      );
6000     print h1('CGI with Style'),
6001           p({-class=>'Tip'},
6002             "Better read the cascading style sheet spec before playing with this!"),
6003           span({-style=>'color: magenta'},
6004                "Look Mom, no hands!",
6005                p(),
6006                "Whooo wee!"
6007                );
6008     print end_html;
6009
6010 Pass an array reference to B<-style> in order to incorporate multiple
6011 stylesheets into your document.
6012
6013 =head1 DEBUGGING
6014
6015 If you are running the script from the command line or in the perl
6016 debugger, you can pass the script a list of keywords or
6017 parameter=value pairs on the command line or from standard input (you
6018 don't have to worry about tricking your script into reading from
6019 environment variables).  You can pass keywords like this:
6020
6021     your_script.pl keyword1 keyword2 keyword3
6022
6023 or this:
6024
6025    your_script.pl keyword1+keyword2+keyword3
6026
6027 or this:
6028
6029     your_script.pl name1=value1 name2=value2
6030
6031 or this:
6032
6033     your_script.pl name1=value1&name2=value2
6034
6035 To turn off this feature, use the -no_debug pragma.
6036
6037 To test the POST method, you may enable full debugging with the -debug
6038 pragma.  This will allow you to feed newline-delimited name=value
6039 pairs to the script on standard input.
6040
6041 When debugging, you can use quotes and backslashes to escape
6042 characters in the familiar shell manner, letting you place
6043 spaces and other funny characters in your parameter=value
6044 pairs:
6045
6046    your_script.pl "name1='I am a long value'" "name2=two\ words"
6047
6048 =head2 DUMPING OUT ALL THE NAME/VALUE PAIRS
6049
6050 The Dump() method produces a string consisting of all the query's
6051 name/value pairs formatted nicely as a nested list.  This is useful
6052 for debugging purposes:
6053
6054     print $query->Dump
6055
6056
6057 Produces something that looks like:
6058
6059     <UL>
6060     <LI>name1
6061         <UL>
6062         <LI>value1
6063         <LI>value2
6064         </UL>
6065     <LI>name2
6066         <UL>
6067         <LI>value1
6068         </UL>
6069     </UL>
6070
6071 As a shortcut, you can interpolate the entire CGI object into a string
6072 and it will be replaced with the a nice HTML dump shown above:
6073
6074     $query=new CGI;
6075     print "<H2>Current Values</H2> $query\n";
6076
6077 =head1 FETCHING ENVIRONMENT VARIABLES
6078
6079 Some of the more useful environment variables can be fetched
6080 through this interface.  The methods are as follows:
6081
6082 =over 4
6083
6084 =item B<Accept()>
6085
6086 Return a list of MIME types that the remote browser accepts. If you
6087 give this method a single argument corresponding to a MIME type, as in
6088 $query->Accept('text/html'), it will return a floating point value
6089 corresponding to the browser's preference for this type from 0.0
6090 (don't want) to 1.0.  Glob types (e.g. text/*) in the browser's accept
6091 list are handled correctly.
6092
6093 Note that the capitalization changed between version 2.43 and 2.44 in
6094 order to avoid conflict with Perl's accept() function.
6095
6096 =item B<raw_cookie()>
6097
6098 Returns the HTTP_COOKIE variable, an HTTP extension implemented by
6099 Netscape browsers version 1.1 and higher, and all versions of Internet
6100 Explorer.  Cookies have a special format, and this method call just
6101 returns the raw form (?cookie dough).  See cookie() for ways of
6102 setting and retrieving cooked cookies.
6103
6104 Called with no parameters, raw_cookie() returns the packed cookie
6105 structure.  You can separate it into individual cookies by splitting
6106 on the character sequence "; ".  Called with the name of a cookie,
6107 retrieves the B<unescaped> form of the cookie.  You can use the
6108 regular cookie() method to get the names, or use the raw_fetch()
6109 method from the CGI::Cookie module.
6110
6111 =item B<user_agent()>
6112
6113 Returns the HTTP_USER_AGENT variable.  If you give
6114 this method a single argument, it will attempt to
6115 pattern match on it, allowing you to do something
6116 like $query->user_agent(netscape);
6117
6118 =item B<path_info()>
6119
6120 Returns additional path information from the script URL.
6121 E.G. fetching /cgi-bin/your_script/additional/stuff will result in
6122 $query->path_info() returning "/additional/stuff".
6123
6124 NOTE: The Microsoft Internet Information Server
6125 is broken with respect to additional path information.  If
6126 you use the Perl DLL library, the IIS server will attempt to
6127 execute the additional path information as a Perl script.
6128 If you use the ordinary file associations mapping, the
6129 path information will be present in the environment,
6130 but incorrect.  The best thing to do is to avoid using additional
6131 path information in CGI scripts destined for use with IIS.
6132
6133 =item B<path_translated()>
6134
6135 As per path_info() but returns the additional
6136 path information translated into a physical path, e.g.
6137 "/usr/local/etc/httpd/htdocs/additional/stuff".
6138
6139 The Microsoft IIS is broken with respect to the translated
6140 path as well.
6141
6142 =item B<remote_host()>
6143
6144 Returns either the remote host name or IP address.
6145 if the former is unavailable.
6146
6147 =item B<script_name()>
6148
6149 Return the script name as a partial URL, for self-refering
6150 scripts.
6151
6152 =item B<referer()>
6153
6154 Return the URL of the page the browser was viewing
6155 prior to fetching your script.  Not available for all
6156 browsers.
6157
6158 =item B<auth_type ()>
6159
6160 Return the authorization/verification method in use for this
6161 script, if any.
6162
6163 =item B<server_name ()>
6164
6165 Returns the name of the server, usually the machine's host
6166 name.
6167
6168 =item B<virtual_host ()>
6169
6170 When using virtual hosts, returns the name of the host that
6171 the browser attempted to contact
6172
6173 =item B<server_port ()>
6174
6175 Return the port that the server is listening on.
6176
6177 =item B<server_software ()>
6178
6179 Returns the server software and version number.
6180
6181 =item B<remote_user ()>
6182
6183 Return the authorization/verification name used for user
6184 verification, if this script is protected.
6185
6186 =item B<user_name ()>
6187
6188 Attempt to obtain the remote user's name, using a variety of different
6189 techniques.  This only works with older browsers such as Mosaic.
6190 Newer browsers do not report the user name for privacy reasons!
6191
6192 =item B<request_method()>
6193
6194 Returns the method used to access your script, usually
6195 one of 'POST', 'GET' or 'HEAD'.
6196
6197 =item B<content_type()>
6198
6199 Returns the content_type of data submitted in a POST, generally
6200 multipart/form-data or application/x-www-form-urlencoded
6201
6202 =item B<http()>
6203
6204 Called with no arguments returns the list of HTTP environment
6205 variables, including such things as HTTP_USER_AGENT,
6206 HTTP_ACCEPT_LANGUAGE, and HTTP_ACCEPT_CHARSET, corresponding to the
6207 like-named HTTP header fields in the request.  Called with the name of
6208 an HTTP header field, returns its value.  Capitalization and the use
6209 of hyphens versus underscores are not significant.
6210
6211 For example, all three of these examples are equivalent:
6212
6213    $requested_language = $q->http('Accept-language');
6214    $requested_language = $q->http('Accept_language');
6215    $requested_language = $q->http('HTTP_ACCEPT_LANGUAGE');
6216
6217 =item B<https()>
6218
6219 The same as I<http()>, but operates on the HTTPS environment variables
6220 present when the SSL protocol is in effect.  Can be used to determine
6221 whether SSL is turned on.
6222
6223 =back
6224
6225 =head1 USING NPH SCRIPTS
6226
6227 NPH, or "no-parsed-header", scripts bypass the server completely by
6228 sending the complete HTTP header directly to the browser.  This has
6229 slight performance benefits, but is of most use for taking advantage
6230 of HTTP extensions that are not directly supported by your server,
6231 such as server push and PICS headers.
6232
6233 Servers use a variety of conventions for designating CGI scripts as
6234 NPH.  Many Unix servers look at the beginning of the script's name for
6235 the prefix "nph-".  The Macintosh WebSTAR server and Microsoft's
6236 Internet Information Server, in contrast, try to decide whether a
6237 program is an NPH script by examining the first line of script output.
6238
6239
6240 CGI.pm supports NPH scripts with a special NPH mode.  When in this
6241 mode, CGI.pm will output the necessary extra header information when
6242 the header() and redirect() methods are
6243 called.
6244
6245 The Microsoft Internet Information Server requires NPH mode.  As of version
6246 2.30, CGI.pm will automatically detect when the script is running under IIS
6247 and put itself into this mode.  You do not need to do this manually, although
6248 it won't hurt anything if you do.
6249
6250 There are a number of ways to put CGI.pm into NPH mode:
6251
6252 =over 4
6253
6254 =item In the B<use> statement
6255
6256 Simply add the "-nph" pragmato the list of symbols to be imported into
6257 your script:
6258
6259       use CGI qw(:standard -nph)
6260
6261 =item By calling the B<nph()> method:
6262
6263 Call B<nph()> with a non-zero parameter at any point after using CGI.pm in your program.
6264
6265       CGI->nph(1)
6266
6267 =item By using B<-nph> parameters
6268
6269 in the B<header()> and B<redirect()>  statements:
6270
6271       print $q->header(-nph=>1);
6272
6273 =back
6274
6275 =head1 Server Push
6276
6277 CGI.pm provides four simple functions for producing multipart
6278 documents of the type needed to implement server push.  These
6279 functions were graciously provided by Ed Jordan <ed@fidalgo.net>.  To
6280 import these into your namespace, you must import the ":push" set.
6281 You are also advised to put the script into NPH mode and to set $| to
6282 1 to avoid buffering problems.
6283
6284 Here is a simple script that demonstrates server push:
6285
6286   #!/usr/local/bin/perl
6287   use CGI qw/:push -nph/;
6288   $| = 1;
6289   print multipart_init(-boundary=>'----here we go!');
6290   foreach (0 .. 4) {
6291       print multipart_start(-type=>'text/plain'),
6292             "The current time is ",scalar(localtime),"\n";
6293       if ($_ < 4) {
6294               print multipart_end;
6295       } else {
6296               print multipart_final;
6297       }
6298       sleep 1;
6299   }
6300
6301 This script initializes server push by calling B<multipart_init()>.
6302 It then enters a loop in which it begins a new multipart section by
6303 calling B<multipart_start()>, prints the current local time,
6304 and ends a multipart section with B<multipart_end()>.  It then sleeps
6305 a second, and begins again. On the final iteration, it ends the
6306 multipart section with B<multipart_final()> rather than with
6307 B<multipart_end()>.
6308
6309 =over 4
6310
6311 =item multipart_init()
6312
6313   multipart_init(-boundary=>$boundary);
6314
6315 Initialize the multipart system.  The -boundary argument specifies
6316 what MIME boundary string to use to separate parts of the document.
6317 If not provided, CGI.pm chooses a reasonable boundary for you.
6318
6319 =item multipart_start()
6320
6321   multipart_start(-type=>$type)
6322
6323 Start a new part of the multipart document using the specified MIME
6324 type.  If not specified, text/html is assumed.
6325
6326 =item multipart_end()
6327
6328   multipart_end()
6329
6330 End a part.  You must remember to call multipart_end() once for each
6331 multipart_start(), except at the end of the last part of the multipart
6332 document when multipart_final() should be called instead of multipart_end().
6333
6334 =item multipart_final()
6335
6336   multipart_final()
6337
6338 End all parts.  You should call multipart_final() rather than
6339 multipart_end() at the end of the last part of the multipart document.
6340
6341 =back
6342
6343 Users interested in server push applications should also have a look
6344 at the CGI::Push module.
6345
6346 Only Netscape Navigator supports server push.  Internet Explorer
6347 browsers do not.
6348
6349 =head1 Avoiding Denial of Service Attacks
6350
6351 A potential problem with CGI.pm is that, by default, it attempts to
6352 process form POSTings no matter how large they are.  A wily hacker
6353 could attack your site by sending a CGI script a huge POST of many
6354 megabytes.  CGI.pm will attempt to read the entire POST into a
6355 variable, growing hugely in size until it runs out of memory.  While
6356 the script attempts to allocate the memory the system may slow down
6357 dramatically.  This is a form of denial of service attack.
6358
6359 Another possible attack is for the remote user to force CGI.pm to
6360 accept a huge file upload.  CGI.pm will accept the upload and store it
6361 in a temporary directory even if your script doesn't expect to receive
6362 an uploaded file.  CGI.pm will delete the file automatically when it
6363 terminates, but in the meantime the remote user may have filled up the
6364 server's disk space, causing problems for other programs.
6365
6366 The best way to avoid denial of service attacks is to limit the amount
6367 of memory, CPU time and disk space that CGI scripts can use.  Some Web
6368 servers come with built-in facilities to accomplish this. In other
6369 cases, you can use the shell I<limit> or I<ulimit>
6370 commands to put ceilings on CGI resource usage.
6371
6372
6373 CGI.pm also has some simple built-in protections against denial of
6374 service attacks, but you must activate them before you can use them.
6375 These take the form of two global variables in the CGI name space:
6376
6377 =over 4
6378
6379 =item B<$CGI::POST_MAX>
6380
6381 If set to a non-negative integer, this variable puts a ceiling
6382 on the size of POSTings, in bytes.  If CGI.pm detects a POST
6383 that is greater than the ceiling, it will immediately exit with an error
6384 message.  This value will affect both ordinary POSTs and
6385 multipart POSTs, meaning that it limits the maximum size of file
6386 uploads as well.  You should set this to a reasonably high
6387 value, such as 1 megabyte.
6388
6389 =item B<$CGI::DISABLE_UPLOADS>
6390
6391 If set to a non-zero value, this will disable file uploads
6392 completely.  Other fill-out form values will work as usual.
6393
6394 =back
6395
6396 You can use these variables in either of two ways.
6397
6398 =over 4
6399
6400 =item B<1. On a script-by-script basis>
6401
6402 Set the variable at the top of the script, right after the "use" statement:
6403
6404     use CGI qw/:standard/;
6405     use CGI::Carp 'fatalsToBrowser';
6406     $CGI::POST_MAX=1024 * 100;  # max 100K posts
6407     $CGI::DISABLE_UPLOADS = 1;  # no uploads
6408
6409 =item B<2. Globally for all scripts>
6410
6411 Open up CGI.pm, find the definitions for $POST_MAX and
6412 $DISABLE_UPLOADS, and set them to the desired values.  You'll
6413 find them towards the top of the file in a subroutine named
6414 initialize_globals().
6415
6416 =back
6417
6418 An attempt to send a POST larger than $POST_MAX bytes will cause
6419 I<param()> to return an empty CGI parameter list.  You can test for
6420 this event by checking I<cgi_error()>, either after you create the CGI
6421 object or, if you are using the function-oriented interface, call
6422 <param()> for the first time.  If the POST was intercepted, then
6423 cgi_error() will return the message "413 POST too large".
6424
6425 This error message is actually defined by the HTTP protocol, and is
6426 designed to be returned to the browser as the CGI script's status
6427  code.  For example:
6428
6429    $uploaded_file = param('upload');
6430    if (!$uploaded_file && cgi_error()) {
6431       print header(-status=>cgi_error());
6432       exit 0;
6433    }
6434
6435 However it isn't clear that any browser currently knows what to do
6436 with this status code.  It might be better just to create an
6437 HTML page that warns the user of the problem.
6438
6439 =head1 COMPATIBILITY WITH CGI-LIB.PL
6440
6441 To make it easier to port existing programs that use cgi-lib.pl the
6442 compatibility routine "ReadParse" is provided.  Porting is simple:
6443
6444 OLD VERSION
6445     require "cgi-lib.pl";
6446     &ReadParse;
6447     print "The value of the antique is $in{antique}.\n";
6448
6449 NEW VERSION
6450     use CGI;
6451     CGI::ReadParse
6452     print "The value of the antique is $in{antique}.\n";
6453
6454 CGI.pm's ReadParse() routine creates a tied variable named %in,
6455 which can be accessed to obtain the query variables.  Like
6456 ReadParse, you can also provide your own variable.  Infrequently
6457 used features of ReadParse, such as the creation of @in and $in
6458 variables, are not supported.
6459
6460 Once you use ReadParse, you can retrieve the query object itself
6461 this way:
6462
6463     $q = $in{CGI};
6464     print $q->textfield(-name=>'wow',
6465                         -value=>'does this really work?');
6466
6467 This allows you to start using the more interesting features
6468 of CGI.pm without rewriting your old scripts from scratch.
6469
6470 =head1 AUTHOR INFORMATION
6471
6472 Copyright 1995-1998, Lincoln D. Stein.  All rights reserved.
6473
6474 This library is free software; you can redistribute it and/or modify
6475 it under the same terms as Perl itself.
6476
6477 Address bug reports and comments to: lstein@cshl.org.  When sending
6478 bug reports, please provide the version of CGI.pm, the version of
6479 Perl, the name and version of your Web server, and the name and
6480 version of the operating system you are using.  If the problem is even
6481 remotely browser dependent, please provide information about the
6482 affected browers as well.
6483
6484 =head1 CREDITS
6485
6486 Thanks very much to:
6487
6488 =over 4
6489
6490 =item Matt Heffron (heffron@falstaff.css.beckman.com)
6491
6492 =item James Taylor (james.taylor@srs.gov)
6493
6494 =item Scott Anguish <sanguish@digifix.com>
6495
6496 =item Mike Jewell (mlj3u@virginia.edu)
6497
6498 =item Timothy Shimmin (tes@kbs.citri.edu.au)
6499
6500 =item Joergen Haegg (jh@axis.se)
6501
6502 =item Laurent Delfosse (delfosse@delfosse.com)
6503
6504 =item Richard Resnick (applepi1@aol.com)
6505
6506 =item Craig Bishop (csb@barwonwater.vic.gov.au)
6507
6508 =item Tony Curtis (tc@vcpc.univie.ac.at)
6509
6510 =item Tim Bunce (Tim.Bunce@ig.co.uk)
6511
6512 =item Tom Christiansen (tchrist@convex.com)
6513
6514 =item Andreas Koenig (k@franz.ww.TU-Berlin.DE)
6515
6516 =item Tim MacKenzie (Tim.MacKenzie@fulcrum.com.au)
6517
6518 =item Kevin B. Hendricks (kbhend@dogwood.tyler.wm.edu)
6519
6520 =item Stephen Dahmen (joyfire@inxpress.net)
6521
6522 =item Ed Jordan (ed@fidalgo.net)
6523
6524 =item David Alan Pisoni (david@cnation.com)
6525
6526 =item Doug MacEachern (dougm@opengroup.org)
6527
6528 =item Robin Houston (robin@oneworld.org)
6529
6530 =item ...and many many more...
6531
6532 for suggestions and bug fixes.
6533
6534 =back
6535
6536 =head1 A COMPLETE EXAMPLE OF A SIMPLE FORM-BASED SCRIPT
6537
6538
6539         #!/usr/local/bin/perl
6540
6541         use CGI;
6542
6543         $query = new CGI;
6544
6545         print $query->header;
6546         print $query->start_html("Example CGI.pm Form");
6547         print "<H1> Example CGI.pm Form</H1>\n";
6548         &print_prompt($query);
6549         &do_work($query);
6550         &print_tail;
6551         print $query->end_html;
6552
6553         sub print_prompt {
6554            my($query) = @_;
6555
6556            print $query->start_form;
6557            print "<EM>What's your name?</EM><BR>";
6558            print $query->textfield('name');
6559            print $query->checkbox('Not my real name');
6560
6561            print "<P><EM>Where can you find English Sparrows?</EM><BR>";
6562            print $query->checkbox_group(
6563                                  -name=>'Sparrow locations',
6564                                  -values=>[England,France,Spain,Asia,Hoboken],
6565                                  -linebreak=>'yes',
6566                                  -defaults=>[England,Asia]);
6567
6568            print "<P><EM>How far can they fly?</EM><BR>",
6569                 $query->radio_group(
6570                         -name=>'how far',
6571                         -values=>['10 ft','1 mile','10 miles','real far'],
6572                         -default=>'1 mile');
6573
6574            print "<P><EM>What's your favorite color?</EM>  ";
6575            print $query->popup_menu(-name=>'Color',
6576                                     -values=>['black','brown','red','yellow'],
6577                                     -default=>'red');
6578
6579            print $query->hidden('Reference','Monty Python and the Holy Grail');
6580
6581            print "<P><EM>What have you got there?</EM><BR>";
6582            print $query->scrolling_list(
6583                          -name=>'possessions',
6584                          -values=>['A Coconut','A Grail','An Icon',
6585                                    'A Sword','A Ticket'],
6586                          -size=>5,
6587                          -multiple=>'true');
6588
6589            print "<P><EM>Any parting comments?</EM><BR>";
6590            print $query->textarea(-name=>'Comments',
6591                                   -rows=>10,
6592                                   -columns=>50);
6593
6594            print "<P>",$query->reset;
6595            print $query->submit('Action','Shout');
6596            print $query->submit('Action','Scream');
6597            print $query->endform;
6598            print "<HR>\n";
6599         }
6600
6601         sub do_work {
6602            my($query) = @_;
6603            my(@values,$key);
6604
6605            print "<H2>Here are the current settings in this form</H2>";
6606
6607            foreach $key ($query->param) {
6608               print "<STRONG>$key</STRONG> -> ";
6609               @values = $query->param($key);
6610               print join(", ",@values),"<BR>\n";
6611           }
6612         }
6613
6614         sub print_tail {
6615            print <<END;
6616         <HR>
6617         <ADDRESS>Lincoln D. Stein</ADDRESS><BR>
6618         <A HREF="/">Home Page</A>
6619         END
6620         }
6621
6622 =head1 BUGS
6623
6624 This module has grown large and monolithic.  Furthermore it's doing many
6625 things, such as handling URLs, parsing CGI input, writing HTML, etc., that
6626 are also done in the LWP modules. It should be discarded in favor of
6627 the CGI::* modules, but somehow I continue to work on it.
6628
6629 Note that the code is truly contorted in order to avoid spurious
6630 warnings when programs are run with the B<-w> switch.
6631
6632 =head1 SEE ALSO
6633
6634 L<CGI::Carp>, L<URI::URL>, L<CGI::Request>, L<CGI::MiniSvr>,
6635 L<CGI::Base>, L<CGI::Form>, L<CGI::Push>, L<CGI::Fast>,
6636 L<CGI::Pretty>
6637
6638 =cut
6639