lib/perl5/5.6.1/syslog.pl

   1 #
   2 # syslog.pl
   3 #
   4 # $Log: syslog.pl,v $
   5 #
   6 # tom christiansen <tchrist@convex.com>
   7 # modified to use sockets by Larry Wall <lwall@jpl-devvax.jpl.nasa.gov>
   8 # NOTE: openlog now takes three arguments, just like openlog(3)
   9 #
  10 # call syslog() with a string priority and a list of printf() args
  11 # like syslog(3)
  12 #
  13 #  usage: require 'syslog.pl';
  14 #
  15 #  then (put these all in a script to test function)
  16 #
  17 #
  18 #       do openlog($program,'cons,pid','user');
  19 #       do syslog('info','this is another test');
  20 #       do syslog('mail|warning','this is a better test: %d', time);
  21 #       do closelog();
  22 #
  23 #       do syslog('debug','this is the last test');
  24 #       do openlog("$program $$",'ndelay','user');
  25 #       do syslog('notice','fooprogram: this is really done');
  26 #
  27 #       $! = 55;
  28 #       do syslog('info','problem was %m'); # %m == $! in syslog(3)
  29
  30 package syslog;
  31
  32 use warnings::register;
  33
  34 $host = 'localhost' unless $host;       # set $syslog'host to change
  35
  36 if ($] >= 5 && warnings::enabled()) {
  37     warnings::warn("You should 'use Sys::Syslog' instead; continuing");
  38 }
  39
  40 require 'syslog.ph';
  41
  42  eval 'use Socket; 1'                   ||
  43      eval { require "socket.ph" }       ||
  44      require "sys/socket.ph";
  45
  46 $maskpri = &LOG_UPTO(&LOG_DEBUG);
  47
  48 sub main'openlog {
  49     ($ident, $logopt, $facility) = @_;  # package vars
  50     $lo_pid = $logopt =~ /\bpid\b/;
  51     $lo_ndelay = $logopt =~ /\bndelay\b/;
  52     $lo_cons = $logopt =~ /\bcons\b/;
  53     $lo_nowait = $logopt =~ /\bnowait\b/;
  54     &connect if $lo_ndelay;
  55 }
  56
  57 sub main'closelog {
  58     $facility = $ident = '';
  59     &disconnect;
  60 }
  61
  62 sub main'setlogmask {
  63     local($oldmask) = $maskpri;
  64     $maskpri = shift;
  65     $oldmask;
  66 }
  67
  68 sub main'syslog {
  69     local($priority) = shift;
  70     local($mask) = shift;
  71     local($message, $whoami);
  72     local(@words, $num, $numpri, $numfac, $sum);
  73     local($facility) = $facility;       # may need to change temporarily.
  74
  75     die "syslog: expected both priority and mask" unless $mask && $priority;
  76
  77     @words = split(/\W+/, $priority, 2);# Allow "level" or "level|facility".
  78     undef $numpri;
  79     undef $numfac;
  80     foreach (@words) {
  81         $num = &xlate($_);              # Translate word to number.
  82         if (/^kern$/ || $num < 0) {
  83             die "syslog: invalid level/facility: $_\n";
  84         }
  85         elsif ($num <= &LOG_PRIMASK) {
  86             die "syslog: too many levels given: $_\n" if defined($numpri);
  87             $numpri = $num;
  88             return 0 unless &LOG_MASK($numpri) & $maskpri;
  89         }
  90         else {
  91             die "syslog: too many facilities given: $_\n" if defined($numfac);
  92             $facility = $_;
  93             $numfac = $num;
  94         }
  95     }
  96
  97     die "syslog: level must be given\n" unless defined($numpri);
  98
  99     if (!defined($numfac)) {    # Facility not specified in this call.
 100         $facility = 'user' unless $facility;
 101         $numfac = &xlate($facility);
 102     }
 103
 104     &connect unless $connected;
 105
 106     $whoami = $ident;
 107
 108     if (!$ident && $mask =~ /^(\S.*):\s?(.*)/) {
 109         $whoami = $1;
 110         $mask = $2;
 111     }
 112
 113     unless ($whoami) {
 114         ($whoami = getlogin) ||
 115             ($whoami = getpwuid($<)) ||
 116                 ($whoami = 'syslog');
 117     }
 118
 119     $whoami .= "[$$]" if $lo_pid;
 120
 121     $mask =~ s/%m/$!/g;
 122     $mask .= "\n" unless $mask =~ /\n$/;
 123     $message = sprintf ($mask, @_);
 124
 125     $sum = $numpri + $numfac;
 126     unless (send(SYSLOG,"<$sum>$whoami: $message",0)) {
 127         if ($lo_cons) {
 128             if ($pid = fork) {
 129                 unless ($lo_nowait) {
 130                     do {$died = wait;} until $died == $pid || $died < 0;
 131                 }
 132             }
 133             else {
 134                 open(CONS,">/dev/console");
 135                 print CONS "<$facility.$priority>$whoami: $message\r";
 136                 exit if defined $pid;           # if fork failed, we're parent
 137                 close CONS;
 138             }
 139         }
 140     }
 141 }
 142
 143 sub xlate {
 144     local($name) = @_;
 145     $name = uc $name;
 146     $name = "LOG_$name" unless $name =~ /^LOG_/;
 147     $name = "syslog'$name";
 148     defined &$name ? &$name : -1;
 149 }
 150
 151 sub connect {
 152     $pat = 'S n C4 x8';
 153
 154     $af_unix = &AF_UNIX;
 155     $af_inet = &AF_INET;
 156
 157     $stream = &SOCK_STREAM;
 158     $datagram = &SOCK_DGRAM;
 159
 160     ($name,$aliases,$proto) = getprotobyname('udp');
 161     $udp = $proto;
 162
 163     ($name,$aliases,$port,$proto) = getservbyname('syslog','udp');
 164     $syslog = $port;
 165
 166     if (chop($myname = `hostname`)) {
 167         ($name,$aliases,$addrtype,$length,@addrs) = gethostbyname($myname);
 168         die "Can't lookup $myname\n" unless $name;
 169         @bytes = unpack("C4",$addrs[0]);
 170     }
 171     else {
 172         @bytes = (0,0,0,0);
 173     }
 174     $this = pack($pat, $af_inet, 0, @bytes);
 175
 176     if ($host =~ /^\d+\./) {
 177         @bytes = split(/\./,$host);
 178     }
 179     else {
 180         ($name,$aliases,$addrtype,$length,@addrs) = gethostbyname($host);
 181         die "Can't lookup $host\n" unless $name;
 182         @bytes = unpack("C4",$addrs[0]);
 183     }
 184     $that = pack($pat,$af_inet,$syslog,@bytes);
 185
 186     socket(SYSLOG,$af_inet,$datagram,$udp) || die "socket: $!\n";
 187     bind(SYSLOG,$this) || die "bind: $!\n";
 188     connect(SYSLOG,$that) || die "connect: $!\n";
 189
 190     local($old) = select(SYSLOG); $| = 1; select($old);
 191     $connected = 1;
 192 }
 193
 194 sub disconnect {
 195     close SYSLOG;
 196     $connected = 0;
 197 }
 198
 199 1;