etc/texi2pod.pl

   1 #! /usr/bin/perl -w
   2
   3 #   Copyright (C) 1999-2019 Free Software Foundation, Inc.
   4
   5 # This file is part of GCC.
   6
   7 # GCC is free software; you can redistribute it and/or modify
   8 # it under the terms of the GNU General Public License as published by
   9 # the Free Software Foundation; either version 2, or (at your option)
  10 # any later version.
  11
  12 # GCC is distributed in the hope that it will be useful,
  13 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 # GNU General Public License for more details.
  16
  17 # You should have received a copy of the GNU General Public License
  18 # along with GCC; see the file COPYING.  If not, write to
  19 # the Free Software Foundation, 51 Franklin Street, Fifth Floor,
  20 # Boston MA 02110-1301, USA.
  21
  22 # This does trivial (and I mean _trivial_) conversion of Texinfo
  23 # markup to Perl POD format.  It's intended to be used to extract
  24 # something suitable for a manpage from a Texinfo document.
  25
  26 $output = 0;
  27 $skipping = 0;
  28 %sects = ();
  29 $section = "";
  30 @icstack = ();
  31 @endwstack = ();
  32 @skstack = ();
  33 @instack = ();
  34 $shift = "";
  35 %defs = ();
  36 $fnno = 1;
  37 $inf = "";
  38 $ibase = "";
  39 @ipath = ();
  40
  41 while ($_ = shift) {
  42     if (/^-D(.*)$/) {
  43         if ($1 ne "") {
  44             $flag = $1;
  45         } else {
  46             $flag = shift;
  47         }
  48         $value = "";
  49         ($flag, $value) = ($flag =~ /^([^=]+)(?:=(.+))?/);
  50         die "no flag specified for -D\n"
  51             unless $flag ne "";
  52         die "flags may only contain letters, digits, hyphens, dashes and underscores\n"
  53             unless $flag =~ /^[a-zA-Z0-9_-]+$/;
  54         $defs{$flag} = $value;
  55     } elsif (/^-I(.*)$/) {
  56         if ($1 ne "") {
  57             $flag = $1;
  58         } else {
  59             $flag = shift;
  60         }
  61         push (@ipath, $flag);
  62     } elsif (/^-/) {
  63         usage();
  64     } else {
  65         $in = $_, next unless defined $in;
  66         $out = $_, next unless defined $out;
  67         usage();
  68     }
  69 }
  70
  71 if (defined $in) {
  72     $inf = gensym();
  73     open($inf, "<$in") or die "opening \"$in\": $!\n";
  74     $ibase = $1 if $in =~ m|^(.+)/[^/]+$|;
  75 } else {
  76     $inf = \*STDIN;
  77 }
  78
  79 if (defined $out) {
  80     open(STDOUT, ">$out") or die "opening \"$out\": $!\n";
  81 }
  82
  83 while(defined $inf) {
  84 while(<$inf>) {
  85     # Certain commands are discarded without further processing.
  86     /^\@(?:
  87          [a-z]+index            # @*index: useful only in complete manual
  88          |need                  # @need: useful only in printed manual
  89          |(?:end\s+)?group      # @group .. @end group: ditto
  90          |page                  # @page: ditto
  91          |node                  # @node: useful only in .info file
  92          |(?:end\s+)?ifnottex   # @ifnottex .. @end ifnottex: use contents
  93         )\b/x and next;
  94
  95     chomp;
  96
  97     # Look for filename and title markers.
  98     /^\@setfilename\s+([^.]+)/ and $fn = $1, next;
  99     /^\@settitle\s+([^.]+)/ and $tl = postprocess($1), next;
 100
 101     # Identify a man title but keep only the one we are interested in.
 102     /^\@c\s+man\s+title\s+([A-Za-z0-9-]+)\s+(.+)/ and do {
 103         if (exists $defs{$1}) {
 104             $fn = $1;
 105             $tl = postprocess($2);
 106         }
 107         next;
 108     };
 109
 110     # Look for blocks surrounded by @c man begin SECTION ... @c man end.
 111     # This really oughta be @ifman ... @end ifman and the like, but such
 112     # would require rev'ing all other Texinfo translators.
 113     /^\@c\s+man\s+begin\s+([A-Z]+)\s+([A-Za-z0-9-]+)/ and do {
 114         $output = 1 if exists $defs{$2};
 115         $sect = $1;
 116         next;
 117     };
 118     /^\@c\s+man\s+begin\s+([A-Z]+)/ and $sect = $1, $output = 1, next;
 119     /^\@c\s+man\s+end/ and do {
 120         $sects{$sect} = "" unless exists $sects{$sect};
 121         $sects{$sect} .= postprocess($section);
 122         $section = "";
 123         $output = 0;
 124         next;
 125     };
 126
 127     # handle variables
 128     /^\@set\s+([a-zA-Z0-9_-]+)\s*(.*)$/ and do {
 129         $defs{$1} = $2;
 130         next;
 131     };
 132     /^\@clear\s+([a-zA-Z0-9_-]+)/ and do {
 133         delete $defs{$1};
 134         next;
 135     };
 136
 137     next unless $output;
 138
 139     # Discard comments.  (Can't do it above, because then we'd never see
 140     # @c man lines.)
 141     /^\@c\b/ and next;
 142
 143     # End-block handler goes up here because it needs to operate even
 144     # if we are skipping.
 145     /^\@end\s+([a-z]+)/ and do {
 146         # Ignore @end foo, where foo is not an operation which may
 147         # cause us to skip, if we are presently skipping.
 148         my $ended = $1;
 149         next if $skipping && $ended !~ /^(?:ifset|ifclear|ignore|menu|iftex|copying)$/;
 150
 151         die "\@end $ended without \@$ended at line $.\n" unless defined $endw;
 152         die "\@$endw ended by \@end $ended at line $.\n" unless $ended eq $endw;
 153
 154         $endw = pop @endwstack;
 155
 156         if ($ended =~ /^(?:ifset|ifclear|ignore|menu|iftex)$/) {
 157             $skipping = pop @skstack;
 158             next;
 159         } elsif ($ended =~ /^(?:example|smallexample|display)$/) {
 160             $shift = "";
 161             $_ = "";    # need a paragraph break
 162         } elsif ($ended =~ /^(?:itemize|enumerate|[fv]?table)$/) {
 163             $_ = "\n=back\n";
 164             $ic = pop @icstack;
 165         } elsif ($ended eq "multitable") {
 166             $_ = "\n=back\n";
 167         } else {
 168             die "unknown command \@end $ended at line $.\n";
 169         }
 170     };
 171
 172     # We must handle commands which can cause skipping even while we
 173     # are skipping, otherwise we will not process nested conditionals
 174     # correctly.
 175     /^\@ifset\s+([a-zA-Z0-9_-]+)/ and do {
 176         push @endwstack, $endw;
 177         push @skstack, $skipping;
 178         $endw = "ifset";
 179         $skipping = 1 unless exists $defs{$1};
 180         next;
 181     };
 182
 183     /^\@ifclear\s+([a-zA-Z0-9_-]+)/ and do {
 184         push @endwstack, $endw;
 185         push @skstack, $skipping;
 186         $endw = "ifclear";
 187         $skipping = 1 if exists $defs{$1};
 188         next;
 189     };
 190
 191     /^\@(ignore|menu|iftex|copying)\b/ and do {
 192         push @endwstack, $endw;
 193         push @skstack, $skipping;
 194         $endw = $1;
 195         $skipping = 1;
 196         next;
 197     };
 198
 199     next if $skipping;
 200
 201     # Character entities.  First the ones that can be replaced by raw text
 202     # or discarded outright:
 203     s/\@copyright\{\}/(c)/g;
 204     s/\@dots\{\}/.../g;
 205     s/\@enddots\{\}/..../g;
 206     s/\@([.!? ])/$1/g;
 207     s/\@[:-]//g;
 208     s/\@bullet(?:\{\})?/*/g;
 209     s/\@TeX\{\}/TeX/g;
 210     s/\@pounds\{\}/\#/g;
 211     s/\@minus(?:\{\})?/-/g;
 212     s/\\,/,/g;
 213
 214     # Now the ones that have to be replaced by special escapes
 215     # (which will be turned back into text by unmunge())
 216     s/&/&amp;/g;
 217     s/\@\{/&lbrace;/g;
 218     s/\@\}/&rbrace;/g;
 219     s/\@\@/&at;/g;
 220
 221     # Inside a verbatim block, handle @var specially.
 222     if ($shift ne "") {
 223         s/\@var\{([^\}]*)\}/<$1>/g;
 224     }
 225
 226     # POD doesn't interpret E<> inside a verbatim block.
 227     if ($shift eq "") {
 228         s/</&lt;/g;
 229         s/>/&gt;/g;
 230     } else {
 231         s/</&LT;/g;
 232         s/>/&GT;/g;
 233     }
 234
 235     # Single line command handlers.
 236
 237     /^\@include\s+(.+)$/ and do {
 238         push @instack, $inf;
 239         $inf = gensym();
 240         $file = postprocess($1);
 241
 242         # Try cwd and $ibase, then explicit -I paths.
 243         $done = 0;
 244         foreach $path ("", $ibase, @ipath) {
 245             $mypath = $file;
 246             $mypath = $path . "/" . $mypath if ($path ne "");
 247             open($inf, "<" . $mypath) and ($done = 1, last);
 248         }
 249         die "cannot find $file" if !$done;
 250         next;
 251     };
 252
 253     /^\@(?:section|unnumbered|unnumberedsec|center)\s+(.+)$/
 254         and $_ = "\n=head2 $1\n";
 255     /^\@subsection\s+(.+)$/
 256         and $_ = "\n=head3 $1\n";
 257     /^\@subsubsection\s+(.+)$/
 258         and $_ = "\n=head4 $1\n";
 259
 260     # Block command handlers:
 261     /^\@itemize(?:\s+(\@[a-z]+|\*|-))?/ and do {
 262         push @endwstack, $endw;
 263         push @icstack, $ic;
 264         if (defined $1) {
 265             $ic = $1;
 266         } else {
 267             $ic = '*';
 268         }
 269         $_ = "\n=over 4\n";
 270         $endw = "itemize";
 271     };
 272
 273     /^\@enumerate(?:\s+([a-zA-Z0-9]+))?/ and do {
 274         push @endwstack, $endw;
 275         push @icstack, $ic;
 276         if (defined $1) {
 277             $ic = $1 . ".";
 278         } else {
 279             $ic = "1.";
 280         }
 281         $_ = "\n=over 4\n";
 282         $endw = "enumerate";
 283     };
 284
 285     /^\@multitable\s.*/ and do {
 286         push @endwstack, $endw;
 287         $endw = "multitable";
 288         $_ = "\n=over 4\n";
 289     };
 290
 291     /^\@([fv]?table)\s+(\@[a-z]+)/ and do {
 292         push @endwstack, $endw;
 293         push @icstack, $ic;
 294         $endw = $1;
 295         $ic = $2;
 296         $ic =~ s/\@(?:samp|strong|key|gcctabopt|env)/B/;
 297         $ic =~ s/\@(?:code|kbd)/C/;
 298         $ic =~ s/\@(?:dfn|var|emph|cite|i)/I/;
 299         $ic =~ s/\@(?:file)/F/;
 300         $_ = "\n=over 4\n";
 301     };
 302
 303     /^\@((?:small)?example|display)/ and do {
 304         push @endwstack, $endw;
 305         $endw = $1;
 306         $shift = "\t";
 307         $_ = "";        # need a paragraph break
 308     };
 309
 310     /^\@item\s+(.*\S)\s*$/ and $endw eq "multitable" and do {
 311         @columns = ();
 312         for $column (split (/\s*\@tab\s*/, $1)) {
 313             # @strong{...} is used a @headitem work-alike
 314             $column =~ s/^\@strong\{(.*)\}$/$1/;
 315             push @columns, $column;
 316         }
 317         $_ = "\n=item ".join (" : ", @columns)."\n";
 318     };
 319
 320     /^\@itemx?\s*(.+)?$/ and do {
 321         if (defined $1) {
 322             # Entity escapes prevent munging by the <> processing below.
 323             $_ = "\n=item $ic\&LT;$1\&GT;\n";
 324         } else {
 325             $_ = "\n=item $ic\n";
 326             $ic =~ y/A-Ya-y/B-Zb-z/;
 327             $ic =~ s/(\d+)/$1 + 1/eg;
 328         }
 329     };
 330
 331     $section .= $shift.$_."\n";
 332 }
 333 # End of current file.
 334 close($inf);
 335 $inf = pop @instack;
 336 }
 337
 338 die "No filename or title\n" unless defined $fn && defined $tl;
 339
 340 $sects{NAME} = "$fn \- $tl\n";
 341 $sects{FOOTNOTES} .= "=back\n" if exists $sects{FOOTNOTES};
 342
 343 for $sect (qw(NAME SYNOPSIS TARGET DESCRIPTION OPTIONS ENVIRONMENT FILES
 344               BUGS NOTES FOOTNOTES SEEALSO AUTHOR COPYRIGHT)) {
 345     if(exists $sects{$sect}) {
 346         $head = $sect;
 347         $head =~ s/SEEALSO/SEE ALSO/;
 348         print "=head1 $head\n\n";
 349         print scalar unmunge ($sects{$sect});
 350         print "\n";
 351     }
 352 }
 353
 354 sub usage
 355 {
 356     die "usage: $0 [-D toggle...] [infile [outfile]]\n";
 357 }
 358
 359 sub postprocess
 360 {
 361     local $_ = $_[0];
 362
 363     # @value{foo} is replaced by whatever 'foo' is defined as.
 364     while (m/(\@value\{([a-zA-Z0-9_-]+)\})/g) {
 365         if (! exists $defs{$2}) {
 366             print STDERR "Option $2 not defined\n";
 367             s/\Q$1\E//;
 368         } else {
 369             $value = $defs{$2};
 370             s/\Q$1\E/$value/;
 371         }
 372     }
 373
 374     # Formatting commands.
 375     # Temporary escape for @r.
 376     s/\@r\{([^\}]*)\}/R<$1>/g;
 377     s/\@(?:dfn|var|emph|cite|i)\{([^\}]*)\}/I<$1>/g;
 378     s/\@(?:code|kbd)\{([^\}]*)\}/C<$1>/g;
 379     s/\@(?:gccoptlist|samp|strong|key|option|env|command|b)\{([^\}]*)\}/B<$1>/g;
 380     s/\@sc\{([^\}]*)\}/\U$1/g;
 381     s/\@file\{([^\}]*)\}/F<$1>/g;
 382     s/\@w\{([^\}]*)\}/S<$1>/g;
 383     s/\@(?:dmn|math)\{([^\}]*)\}/$1/g;
 384
 385     # keep references of the form @ref{...}, print them bold
 386     s/\@(?:ref)\{([^\}]*)\}/B<$1>/g;
 387
 388     # Change double single quotes to double quotes.
 389     s/''/"/g;
 390     s/``/"/g;
 391
 392     # Cross references are thrown away, as are @noindent and @refill.
 393     # (@noindent is impossible in .pod, and @refill is unnecessary.)
 394     # @* is also impossible in .pod; we discard it and any newline that
 395     # follows it.  Similarly, our macro @gol must be discarded.
 396
 397     s/\(?\@xref\{(?:[^\}]*)\}(?:[^.<]|(?:<[^<>]*>))*\.\)?//g;
 398     s/\s+\(\@pxref\{(?:[^\}]*)\}\)//g;
 399     s/;\s+\@pxref\{(?:[^\}]*)\}//g;
 400     s/\@noindent\s*//g;
 401     s/\@refill//g;
 402     s/\@gol//g;
 403     s/\@\*\s*\n?//g;
 404
 405     # Anchors are thrown away
 406     s/\@anchor\{(?:[^\}]*)\}//g;
 407
 408     # @uref can take one, two, or three arguments, with different
 409     # semantics each time.  @url and @email are just like @uref with
 410     # one argument, for our purposes.
 411     s/\@(?:uref|url|email)\{([^\},]*)\}/&lt;B<$1>&gt;/g;
 412     s/\@uref\{([^\},]*),([^\},]*)\}/$2 (C<$1>)/g;
 413     s/\@uref\{([^\},]*),([^\},]*),([^\},]*)\}/$3/g;
 414
 415     # Un-escape <> at this point.
 416     s/&LT;/</g;
 417     s/&GT;/>/g;
 418
 419     # Now un-nest all B<>, I<>, R<>.  Theoretically we could have
 420     # indefinitely deep nesting; in practice, one level suffices.
 421     1 while s/([BIR])<([^<>]*)([BIR])<([^<>]*)>/$1<$2>$3<$4>$1</g;
 422
 423     # Replace R<...> with bare ...; eliminate empty markup, B<>;
 424     # shift white space at the ends of [BI]<...> expressions outside
 425     # the expression.
 426     s/R<([^<>]*)>/$1/g;
 427     s/[BI]<>//g;
 428     s/([BI])<(\s+)([^>]+)>/$2$1<$3>/g;
 429     s/([BI])<([^>]+?)(\s+)>/$1<$2>$3/g;
 430
 431     # Extract footnotes.  This has to be done after all other
 432     # processing because otherwise the regexp will choke on formatting
 433     # inside @footnote.
 434     while (/\@footnote/g) {
 435         s/\@footnote\{([^\}]+)\}/[$fnno]/;
 436         add_footnote($1, $fnno);
 437         $fnno++;
 438     }
 439
 440     return $_;
 441 }
 442
 443 sub unmunge
 444 {
 445     # Replace escaped symbols with their equivalents.
 446     local $_ = $_[0];
 447
 448     s/&lt;/E<lt>/g;
 449     s/&gt;/E<gt>/g;
 450     s/&lbrace;/\{/g;
 451     s/&rbrace;/\}/g;
 452     s/&at;/\@/g;
 453     s/&amp;/&/g;
 454     return $_;
 455 }
 456
 457 sub add_footnote
 458 {
 459     unless (exists $sects{FOOTNOTES}) {
 460         $sects{FOOTNOTES} = "\n=over 4\n\n";
 461     }
 462
 463     $sects{FOOTNOTES} .= "=item $fnno.\n\n"; $fnno++;
 464     $sects{FOOTNOTES} .= $_[0];
 465     $sects{FOOTNOTES} .= "\n\n";
 466 }
 467
 468 # stolen from Symbol.pm
 469 {
 470     my $genseq = 0;
 471     sub gensym
 472     {
 473         my $name = "GEN" . $genseq++;
 474         my $ref = \*{$name};
 475         delete $::{$name};
 476         return $ref;
 477     }
 478 }