package Utils;

use strict;

use IPC::Open2;

use POSIX ":sys_wait_h";

##

# checkCommand(file)

# file: an command's filename.

# Returns: the full path to $file, or undef if $file is not a valid command.

#

# Checks whether $file is an executable which is in $PATH or the working directory.

#

# Example:

# checkCommand('gcc'); # Returns "/usr/bin/gcc"

sub checkCommand {

my ($file, $file2) = split / /, $_[0];

$file = $file2 if ($file =~ /ccache/);

return abs_path($file) if (-x $file);

foreach my $dir (split /:+/, $ENV{PATH}) {

if (-x "$dir/$file") {

return "$dir/$file";

}

}

return undef;

}

sub pipeCommand {

my $input = shift;

my ($r, $w);

my $pid = open2($r, $w, @_);

if (!defined $pid) {

return undef;

}

print $w $input;

close $w;

local($/);

my $output = <$r>;

close $r;

waitpid($pid, 0);

return $output;

}

sub syntaxHighlight {

my ($code) = @_;

our $hasSourceHighlight;

if (!defined $hasSourceHighlight) {

$hasSourceHighlight = checkCommand('highlight');

if (!$hasSourceHighlight) {

print STDERR "WARNING: you don't have 'highlight' (http://www.andre-simon.de/) " .

"installed, so syntax highlighting will be disabled.\n";

}

}

if (!$hasSourceHighlight) {

return $code;

} else {

return pipeCommand($code, qw/highlight -S perl -f/);

}

}

1;