#! /usr/local/bin/perl

eval "exec /usr/local/bin/perl -S $0 $*"
    if $running_under_some_shell;

################################################################################
#
# File:         cleanLinks <source tree>
# RCS:          $XConsortium: cleanLinks /main/3 1995/10/30 13:43:35 rswiston $
# Author:       Marc Ayotte Hewlett-Packard, OSSD-CV
# Created:      Sun Jul  4 17:57:13 PDT 1993
# Language:     perl
# Package:      N/A
# Status:       CDE distributed
#
# (c) Copyright 1993, Hewlett-Packard Company, all rights reserved.
#
# Usage:        cleanLinks <directory>
#
# Description:  This script removes symbolic links to nowhere in
#               <directory>. It does not remove anything with RCS
#               in its path.
#
################################################################################
if ($ARGV[0]) {
	$TREE = $ARGV[0];
}
else {
	die "	USAGE CleanLinks <source directory>\n";
}

if (! chdir("$TREE")) {
	die "	ERROR -> Couldn't change directory to $TREE.\n";
}

#######################################################
# define local subroutines
#######################################################
sub dokill {
	die "\n	left on INTR \n";
	exit 1;
}
########################################################
# Catch signals
########################################################
$SIG{'INT'} = 'dokill';


##############################
# get the symlinks in the tree
##############################
if (! open(FIND,"find . -type d ! -type l -print|")) {
	print STDERR "	ERROR failure in open used for find.\n";
	die "You may have to contact your build administrator\n";
}
#
# don't buffer find output
#
$| = 1;

print "************ List of symlinks to nowhere removed **********\n";


##################################################################
# go through the directories and examine each symlink.
# resolve  the symlink and, if the file at the end doesn't exist,
# remove the original symlink. Don't do anything that ends in RCS.
##################################################################
FILE:
while ($new = <FIND>) {
	chop $new;
	if (! opendir(THISDIR,"$new")) {
		print STDERR "	WARNING -> could not process directory $new\n";
		next FILE;
	}
	else {
		if (! chdir("$new")) {
			print STDERR "	WARNING -> could not change directory to $new\n";
			next FILE;
		}
	}
	# remove . from $new path for cuteness of output
	$new =~ s%^\.%%;

	@allfiles = grep(!/^\.\.?$/, readdir(THISDIR));
	foreach $file (@allfiles) {
		if (( -l $file) && ($file !~ m%RCS$%) && (! -d $file)) {
			#
			# resolve the link
			#
			$tmp1file = $file;
			$counter = 0;
			while (defined($tmp2file = readlink($tmp1file))) {
				$tmp1file = $tmp2file;
				# 
				# watch for cyclic symlinks
				#
				if ($counter++ == 10) {
					last;
				}
			}
			#
			# if last piece in resolved chain is not a file
			# it is a symlink to nowhere -> remove
			#
			if ( ! -e $tmp1file) { # remove link to nowhere
				if (unlink("$file")) {
					print "removing ${TREE}${new}/${file}\n";
				}
				else {
					print STDERR "	WARNING -> ${TREE}${new}/${file} -> could not remove\n";
					print "$!\n";
				}
			}
		}
	}
	closedir(THISDIR);
	if (! chdir("$TREE")) {
		die "	ERROR -> Couldn't change directory to $TREE.\n";
	}
}