#!/usr/bin/perl
use Getopt::Long;
GetOptions('help'   => \$opt{help},
           'tags'   => \$opt{tags},
	   'grep'   => sub{ $style = 'grep' },
	   'func'   => sub{ $style = 'func' });

help() if($opt{help} == 1);

if($opt{tags}){
    open(TAGS,$opt{tags});
    @tags = <TAGS>;
    close(TAGS);
}else{
    @tags = <>;
}

if($style eq 'func'){
    foreach(@tags){
	chomp;
	my($file,$line,$func) = split(/ +/,$_);
	$index{$file} ||= {};
	$index{$file}->{$line} = $func;
    }
}

foreach(@tags){
    chomp;
    my($file,$line,$func) = split(/ +/,$_);
    print "\n" if($continue);
    print "$func($file:$line) called:\n";
    open(GID,"gid $func |");
    @result = <GID>;
    close(GID);
    foreach(@result){
	if($style eq 'grep'){
	    print "  $_";
	}elsif($style eq 'func'){
	    my($file,$line) = split(/:/,$_,3);
	    my($result) = get_pos($file,$line);
	    print "  $file:$result\n" if($result);
	}
    }
    $continue = 1;
}

sub get_pos{
    my($file,$line) = @_;
    my($prev);
    foreach(sort {$a <=> $b} keys %{$index{$file}}){
	if($line > $_){
	    $prev = $index{$file}->{$_};
	}elsif($line == $_){
	    return;
	}else{
	    return $prev;
	}
    }
    
}

sub help{
    print "$0 [--help]\n";
    print "    --help      : Show this message\n";
    exit(0);
}