hex2carray

#!/bin/perl

use strict;
use warnings;
use diagnostics;

##
# Script to parse an Intel Hex file and convert it to an array of bytes
# (plus some other variables).
#
# !!!!! BIG FAT WARNING !!!!!
#
# This will not work on noncontiguous data. It doesn't even check. It assumes
# the first data address is the start and then stuffs all the data into an array,
# in order, keeping count of how many bytes there are. That's it.
#
# !!!!! END BIG FAT WARNING !!!!!

##
# Parse a hex line and return the string to be written to the file.
#
# @param lineno line number
# @param line line to be parsed
# @param length_total the current total length
#
# @return the current length
# @return a string to be printed to the output file.
sub parse_line($$$)
{
    my ($lineno, $line, $length_total) = @_;
    my $output;

    my @chars = split('', $line);

    if ($chars[0] ne ":") {
        print("Error: Line ${lineno} does not start with :\n");
    }
    else {
        # We need the length as a number to correctly parse the data.
        my $length = hex("0x${chars[1]}${chars[2]}");
        $length_total += $length;

        # Only print address on for first line, and we declare our data array.
        if ($lineno == 1) {
            $output .= "const uint16_t firmwareStartAddress = 0x${chars[3]}${chars[4]}${chars[5]}${chars[6]};\n";
            $output .= "const byte firmwareData[] = {\n";
        }

        # We skip the next 2 characters (type)

        if ($length > 0) {
            # proper indenting.
            $output .= "        ";
            for (my $data_index = 0; $data_index < $length; ++$data_index) {
                $output .= "0x${chars[$data_index*2+9]}${chars[$data_index*2+10]},";
            }
        }
        else {
            # last line, end the array.
            $output .= "    };";
        }
        # add a newline at the end.
        $output .= "\n";
    }

    return ($length_total, $output);
}

##
# Print usage
#
sub print_usage()
{
    print("Usage:\n");
    print("    ${0} <input> <output>\n");
}

##
# C programmer writing perl compatibility shim
sub main($@)
{
    my ($argc, @argv) = @_;

    if ($argc != 2) {
        print("Error - incorrect number of arguments.\n");
        print_usage();
    }
    else {
        my $infile = shift(@ARGV);
        my $outfile = shift(@ARGV);

        if (!defined(open(INFH, "<", $infile))) {
            printf("Error opening file ${infile}: $!\n");
        }
        else {
            if (!defined(open(OUTFH, ">", $outfile))) {
                printf("Error opening file ${outfile}: $!\n");
                close(INFH);
            }
            else {
                my $lineno = 0;
                my $length_total = 0;
                my $print_lines;
                while(my $line = <INFH>) {
                    ++$lineno;
                    ($length_total, $print_lines) = parse_line($lineno, $line, $length_total);
                    print(OUTFH $print_lines); 
                }
                print(OUTFH "const size_t firmwareLengthBytes = ${length_total};\n");

                close(OUTFH);
                close(INFH);
            }
        }
    }
}

main(scalar(@ARGV), @ARGV);