ms/segrenam.pl

   1 #!/usr/bin/env perl
   2
   3 my $quiet = 1;
   4
   5 unpack("L",pack("N",1))!=1 || die "only little-endian hosts are supported";
   6
   7 # first argument can specify custom suffix...
   8 $suffix=(@ARGV[0]=~/^\$/) ? shift(@ARGV) : "\$m";
   9 #################################################################
  10 # rename segments in COFF modules according to %map table below #
  11 %map=( ".text"  => "fipstx$suffix",                             #
  12        ".text\$"=> "fipstx$suffix",                             #
  13        ".rdata" => "fipsrd$suffix",                             #
  14        ".data"  => "fipsda$suffix" );                           #
  15 #################################################################
  16
  17 # collect file list
  18 foreach (@ARGV) {
  19     if (/\*/) { push(@files,glob($_)); }
  20     else      { push(@files,$_);       }
  21 }
  22
  23 use Fcntl;
  24 use Fcntl ":seek";
  25
  26 foreach (@files) {
  27     $file=$_;
  28     print "processing $file\n" unless $quiet;
  29
  30     sysopen(FD,$file,O_RDWR|O_BINARY) || die "sysopen($file): $!";
  31
  32     # read IMAGE_DOS_HEADER
  33     sysread(FD,$mz,64)==64 || die "$file is too short";
  34     @dos_header=unpack("a2C58I",$mz);
  35     if (@dos_header[0] eq "MZ") {
  36         $e_lfanew=pop(@dos_header);
  37         sysseek(FD,$e_lfanew,SEEK_SET) || die "$file is too short";
  38         sysread(FD,$Magic,4)==4        || die "$file is too short";
  39         unpack("I",$Magic)==0x4550     || die "$file is not COFF image";
  40     } elsif ($file =~ /\.obj$/i) {
  41         # .obj files have no IMAGE_DOS_HEADER
  42         sysseek(FD,0,SEEK_SET)         || die "unable to rewind $file";
  43     } else { next; }
  44
  45     # read IMAGE_FILE_HEADER
  46     sysread(FD,$coff,20)==20 || die "$file is too short";
  47     ($Machine,$NumberOfSections,$TimeDateStamp,
  48      $PointerToSymbolTable,$NumberOfSysmbols,
  49      $SizeOfOptionalHeader,$Characteristics)=unpack("SSIIISS",$coff);
  50
  51     # skip over IMAGE_OPTIONAL_HEADER
  52     sysseek(FD,$SizeOfOptionalHeader,SEEK_CUR) || die "$file is too short";
  53
  54     # traverse IMAGE_SECTION_HEADER table
  55     for($i=0;$i<$NumberOfSections;$i++) {
  56         sysread(FD,$SectionHeader,40)==40 || die "$file is too short";
  57         ($Name,@opaque)=unpack("Z8C*",$SectionHeader);
  58         if ($map{$Name}) {
  59             sysseek(FD,-40,SEEK_CUR) || die "unable to rewind $file";
  60             syswrite(FD,pack("a8C*",$map{$Name},@opaque))==40 || die "syswrite failed: $!";
  61             printf "    %-8s -> %.8s\n",$Name,$map{$Name} unless $quiet;
  62         }
  63     }
  64     close(FD);
  65 }