configs/config.samples/S001

   1 This script patches an Exim binary in order to change the compiled-in
   2 configuration file name. See FAQ 0065 for a situation in which this might
   3 be a useful thing to do.
   4
   5 ============================================================
   6 #!/usr/local/bin/perl
   7 #
   8 # Patch the config file location in exim so as to avoid using
   9 # exim -C and thus having problems with vacation messages etc.
  10 #
  11 # Placed in the public domain.
  12
  13 # This is the default in exim RPMS.
  14 my $oldconf = "/etc/exim/exim4.conf";
  15
  16 die "Usage: $0 infile outfile configfile\n" unless (@ARGV == 3);
  17 my ($in, $out, $newconf) = @ARGV;
  18
  19 # We mustn't make our string longer than the original!
  20 die "configfile location must be ".length($oldconf)." chars long or less\n"
  21         if (length($newconf) > length($oldconf));
  22
  23 # Get original details.
  24 my @stat = (stat($in));
  25 die "stat($in): $!\n" if (@stat == 0);
  26
  27 # Get original binary.
  28 open(F, "<$in") || die "Can't read $in\n";
  29 read(F, $exim, $stat[7]) || die "Can't read $in\n";
  30 die "Didn't read full data\n" unless (length($exim) == $stat[7]);
  31 close(F);
  32
  33 # Find the old config location.
  34 my $pos = 0;
  35 my @positions = ();
  36 while (($pos = index($exim, $oldconf."\0", $pos)) >= 0)
  37 {
  38         print "Config file name found at byte offset $pos\n";
  39         push(@positions, $pos);
  40         $pos++;
  41 }
  42
  43 die "Old config location ($oldconf) not found\n" if (@positions == 0);
  44
  45 # We could be clever here and try to isolate the correct instance,
  46 # but for now I'm going to assume it's the only instance.
  47 die "Too many possible config locations found\n" if (@positions > 1);
  48
  49 # Patch in the new config location
  50 substr($exim, $positions[0], length($newconf)+1) = $newconf."\0";
  51
  52 # Write out the patched version.
  53 open(F, ">$out") || die "Can't write $out\n";
  54 print F $exim;
  55 close(F);
  56
  57 # Set permissions on new copy to match old.
  58 chmod($stat[2] & 07777, $out);
  59
  60 # Print the config file path.
  61 $out = "./".$out unless ($out =~ m#/#);
  62 print <<EOF;
  63
  64 Trying to run '$out -bP configure_file'. If it has worked
  65 either it will be printed below or you will get a LOG: MAIN PANIC
  66 about it (if the config file doesn't already exist)
  67
  68 EOF
  69 system($out, "-bP", "configure_file");
  70 ============================================================