hex2bin

#!/usr/bin/perl
use strict;
use warnings;
use autodie;

# Get any padding amount
my $numpad=0;
while (defined($ARGV[0]) && ($ARGV[0]=~ m{^-})) {
  if ($ARGV[0] eq "-pad") {
    shift(@ARGV); $numpad=int($ARGV[0]);
    shift(@ARGV); next;
  }
  die("Usage: $0 [-pad NNN] binfile hexfile [hexfile ...]\n");
}

# Print usage if we don't have two arguments
die("Usage: $0 [-pad NNN] binfile hexfile [hexfile ...]\n") if (@ARGV < 2);

# Open the output file
open(my $OUT, '>:raw', $ARGV[0]); shift(@ARGV);

# Process each input file
foreach my $file (@ARGV) {
  open(my $IN, '<', $file);

  while (<$IN>) {
    chomp;
    # Skip lines that have the word "raw" on them
    next if ($_=~ m{raw});

    # Split line into words, convert from hex, save as a byte
    foreach my $hexbyte(split(m{\s+}, $_)) {
      print($OUT pack("C1", hex($hexbyte)));
    }
  }

  close($IN);
}

# Now apply the padding
foreach my $count (1 .. $numpad) {
  print($OUT pack("C1", 0));
}
close($OUT);
exit(0);