/usr/local/lp/apps/malre/scripts/ Current File: //usr/local/lp/apps/malre/scripts/json_io.pm
use warnings;
use strict;
use JSON;

my $f_json;
my $fh_json;

sub fn_read_json {
### Opens a file containing .json data and converts it into a reference document
### $_[0] is the name of the .json file that we're reading from
	if ( ! defined $_[0] ) {
		return;
	}
	$f_json = $_[0];
	my $ref_json;
	$fh_json = fn_get_lock($f_json);
	seek( $fh_json, 0, 0 );
	my @temp = <$fh_json>;
	my $v_json = join( '', @temp );
	if ( ! $v_json ) {
		return;
	}

	### Test if the contents are json; if so, return them
	do { 
		eval {
			decode_json( $v_json );
			1;
		} and do {
			$ref_json = decode_json( $v_json );
			return $ref_json;
		}

	### Otherwise just return
	} or do {
		print STDERR "File \"$f_json\" exists, but does not contain syntactically correct json data.\n";
	}
}

sub fn_write_json {
### converts a reference object to json and writes it to an already open file
### $_[0] is the data object
	if ( ! defined $_[0] ) {
		return;
	}
	my $ref_json = $_[0];
	if ( $ref_json ) {
		my $v_json = encode_json( $ref_json );
		open( my $fh, '>', $f_json) or die "Cannot open " . $f_json . ": $!";
		close( $fh );
		seek( $fh_json, 0, 0 );
		print $fh_json $v_json;
	}
	fn_release_lock($f_json);
	undef $fh_json;
	return;
}

1;