#!/usr/bin/env perl
#
# xxdi.pl - perl implementation of 'xxd -i' mode
#
# Copyright 2013 Greg Kroah-Hartman <gregkh@linuxfoundation.org>
# Copyright 2013 Linux Foundation
#
# Released under the GPLv2.
#
# Implements the "basic" functionality of 'xxd -i' in perl to keep build
# systems from having to build/install/rely on vim-core, which not all
# distros want to do.  But everyone has perl, so use it instead.

use strict;
use warnings;

my $indata              = slurp( @ARGV ? $ARGV[0] : \*STDIN );
my $len_data            = length($indata);
my $num_digits_per_line = 12;
my $var_name;
my $outdata;

# Use the variable name of the file we read from, converting '/' and '.
# to '_', or, if this is stdin, just use "stdin" as the name.
if (@ARGV)
{
    $var_name = $ARGV[0];
    $var_name =~ s/\//_/g;
    $var_name =~ s/\./_/g;
}
else
{
    $var_name = "stdin";
}

$outdata .= "unsigned char $var_name\[] = {";

# trailing ',' is acceptable, so instead of duplicating the logic for
# just the last character, live with the extra ','.
for ( my $key = 0 ; $key < $len_data ; $key++ )
{
    if ( $key % $num_digits_per_line == 0 )
    {
        $outdata .= "\n\t";
    }
    $outdata .= sprintf( "0x%.2x, ", ord( substr( $indata, $key, 1 ) ) );
}

$outdata .= sprintf( "0x00, ");
$outdata .= "\n};\nunsigned int $var_name\_len = $len_data;\n";

binmode STDOUT;
print { *STDOUT } $outdata;


sub slurp
{
    my ($file) = (@_);

    my $txt = "";

    open( my $handle, "<", $file ) or
      die "Failed to open $file - $!";

    while ( my $line = <$handle> )
    {
        $txt .= $line;
    }
    close($handle);
    return ($txt);
}
