#!/usr/bin/perl
#
# vlog: little utility to watch the logs written by sbuild
# Copyright (C) 1999 Roman Hodek <Roman.Hodek@informatik.uni-erlangen.de>
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License as
# published by the Free Software Foundation; either version 2 of the
# License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
#
# $Id$
#

use POSIX;

($main::HOME = $ENV{'HOME'})
	or die "HOME not defined in environment!\n";
$logpath = "$main::HOME/logs";

while( 1 ) {
	
	my $curr_pkg = read_progress();
	if (!$curr_pkg) {
		print "No build-progress -- waiting\n";
		do {
			sleep 5;
		} while (!($curr_pkg = read_progress()));
	}

	my $logf = newest_log( "$logpath/${curr_pkg}_*" );
	print "\n\n", "="x78, "\n$logf:\n\n";

	tail( $logf );
}

sub read_progress {
	my $f = "$main::HOME/build/build-progress";
	my $p = "";
	
	open( F, "<$f" ) || return "";
	while( <F> ) {
		$p = $1 if /^(\S+): currently building/;
	}
	close( F );
	return $p;
}

sub newest_log {
	my $pattern = shift;

	my @f = glob( $pattern );
	my $maxtime = 0;
	my $f = "";
	my @s;
	
	foreach (@f) {
		@s = stat( $_ );
		warn "Cannot stat $_: $!", next if !@s;
		if ($s[9] > $maxtime) {
			$maxtime = $s[9];
			$f = $_;
		}
	}
	return $f;
}

sub tail {
	my $f = shift;

	my @s = stat( $f );
	if (!@s) {
		warn "Cannot stat $f: $!\n";
		return;
	}
	my $size = $s[7];
	
	if (!open( F, "<$f" )) {
		warn "Cannot open $f: $!\n";
		return;
	}
	if ($size > 3*1024) {
		seek( F, -3*1024, SEEK_END );
		my $junk = <F>; # throw away first incomplete line
		print $size+3*1024, " bytes skipped...\n";
	}

	while( 1 ) {
		while( <F> ) {
			print $_;
			if (/^Build needed \d\d:\d\d:\d\d/) {
				close( F );
				return;
			}
		}
		sleep( 2 );
	}
}