package Ksplice;
use Cwd qw(abs_path getcwd);
use Getopt::Long qw(:config bundling);
use File::Basename;
use File::Copy;
use File::Path;
use File::Spec::Functions qw(tmpdir);
use File::Temp qw(tempfile tempdir);
use Fatal qw(:void copy rename move chdir mkdir rmdir unlink rmtree);
use IPC::Open2;
use IPC::Open3;
use Pod::Usage;
use Text::ParseWords;
use strict;
use warnings;
use Verbose qw(:2 copy rename move utime chdir mkdir mkpath unlink rmtree tempfile tempdir);
require Exporter;
our @ISA = qw(Exporter);
our @EXPORT = qw(
	Verbose GetOptions pod2usage shellwords
	$datadir $libexecdir @common_options $help $raw_errors
	child_error runval runval_raw runval_stderr runstr runstr_err runval_in runval_infile runval_outfile
	unpack_update
	get_stage set_stage set_debug_level set_partial get_abort_cause get_partial get_patch update_loaded
	get_debug_output get_conflicts get_raw_conflicts get_short_description
	read_file write_file
	abs_path getcwd basename dirname tmpdir
	copy rename move utime chdir mkdir mkpath unlink rmtree tempfile tempdir
	print_abort_error print_abort_code refcount
);

our ($datadir, $libexecdir) = qw(/usr/lib/uptrack /usr/lib/uptrack);

our $help = 0;
our $raw_errors = 0;
our $printed_abort_code;

our @common_options = (
	"help|?" => \$help,
	"raw-errors" => \$raw_errors,
	"version" => sub { print "Ksplice version 0.9.9\n"; exit(0); },
	"api-version" => sub { print "2\n"; exit(0); },
	"verbose|v:+" => \$Verbose::level,
	"quiet|q:+" => sub { $Verbose::level -= $_[1]; },
);

$SIG{__DIE__} = sub {
	die @_ if $^S || !$raw_errors;
	my ($msg) = @_;
	if(!$printed_abort_code) {
		print STDERR "OTHER\n$msg";
	}
	exit(-1);
};

sub child_error {
	if($raw_errors) {
		return ($? != 0);
	}
	if($? == -1) {
		print STDERR "Failed to exec child\n";
	} elsif(($? & 127) != 0) {
		print STDERR "Child exited with signal ", ($? & 127), ($? & 128) ? " (core dumped)\n" : "\n";
	} elsif($? >> 8 != 0) {
		print STDERR "Child exited with status ", $? >> 8, "\n";
	} else {
		return 0;
	}
	return 1;
}

sub runval {
	my (@cmd) = @_;
	if(runval_raw(@cmd) != 0) {
		child_error();
		die "Failed during: @cmd\n";
	}
}

sub runval_stderr {
	my (@cmd) = @_;
	my ($out, $err);
	print "+ @cmd\n" if($Verbose::level >= 1);
	my $pid = open3(fileno STDIN, ">&STDOUT", \*CMD_ERR, @cmd);
	my $stderr = do { local $/; <CMD_ERR> } || "";

	waitpid($pid, 0);
	print STDERR $stderr unless $raw_errors;
	return ($?, $stderr);
}

sub runval_raw {
	my (@cmd) = @_;
	my ($out, $err);
	print "+ @cmd\n" if($Verbose::level >= 1);
	if($raw_errors) {
		my $pid = open3(fileno STDIN, ">&STDOUT", ">/dev/null", @cmd);
		waitpid($pid, 0);
		return $?;
	} else {
		return system(@cmd);
	}
}

sub runstr {
	my @cmd = @_;
	print "+ @cmd\n" if($Verbose::level >= 1);
	local $/;
	local (*PIPE);
	if($raw_errors) {
		open3(fileno STDIN, \*PIPE, ">/dev/null", @cmd);
	} else {
		open PIPE, '-|', @cmd or die "Can't run @cmd: $!";
	}
	my $output = <PIPE>;
	close PIPE or $! == 0 or die "Can't run @cmd: $!";
	return $output;
}

sub runstr_err {
	my @cmd = @_;
	print "+ @cmd\n" if($Verbose::level >= 1);
	local (*ERROR);
	my $pid = open3(fileno STDIN, '>&STDOUT', \*ERROR, @cmd);
	local $/;
	my $error = <ERROR>;
	waitpid($pid, 0);
	print STDERR $error unless $raw_errors;
	return $error;
}

sub runval_in {
	my ($in, @cmd) = @_;
	print "+ @cmd <<'EOF'\n${in}EOF\n" if($Verbose::level >= 1);
	local (*WRITE);
	if($raw_errors) {
		open3(\*WRITE, ">&STDOUT", ">/dev/null", @cmd);
	} else {
		open(WRITE, '|-', @cmd) or die "Can't run @cmd: $!";
	}
	print WRITE $in;
	close(WRITE) or $! == 0 or die "Can't run @cmd: $!";
	if(child_error()) {
		die "Failed during: @cmd";
	}
}

sub runval_infile {
	my ($infile, @cmd) = @_;
	print "+ @cmd < $infile\n" if($Verbose::level >= 1);
	local (*INFILE);
	open(INFILE, '<', $infile) or die "Can't open $infile: $!";
	my $pid;
	if($raw_errors) {
		$pid = open3('<&INFILE', '>&STDOUT', ">/dev/null", @cmd);
	} else {
		$pid = open2('>&STDOUT', '<&INFILE', @cmd);
	}
	waitpid($pid, 0);
	if(child_error()) {
		die "Failed during: @cmd";
	}
}

sub runval_outfile {
	my ($outfile, @cmd) = @_;
	print "+ @cmd > $outfile\n" if($Verbose::level >= 1);
	local (*OUTFILE);
	open(OUTFILE, '>', $outfile) or die "Can't open $outfile: $!";
	my $pid;
	if($raw_errors) {
		$pid = open3('</dev/null', '>&OUTFILE', ">/dev/null", @cmd);
	} else {
		$pid = open2('>&OUTFILE', '</dev/null', @cmd);
	}
	waitpid($pid, 0);
	if(child_error()) {
		die "Failed during: @cmd";
	}
}

sub unpack_update {
	my ($file) = @_;
	if (-d $file) {
		return $file;
	}
	my $tmpdir = tempdir('ksplice-tmp-XXXXXX', TMPDIR => 1, CLEANUP => 1);
	runval("tar", "-C", $tmpdir, "--force-local", "-zxf", $file);
	my ($ksplice) = glob("$tmpdir/*/");
	chop($ksplice); # remove the trailing slash
	return $ksplice;
}

sub get_sysfs {
	my ($kid) = @_;
	if(! -d "/sys/module") {
		die "/sys not mounted?\n";
	}
	my $update = "ksplice_$kid";
	if (-d "/sys/kernel/ksplice/$kid") {
		return "/sys/kernel/ksplice/$kid";
	}
	if (-d "/sys/module/$update/ksplice") {
		return "/sys/module/$update/ksplice";
	}
	return undef;
}

sub update_loaded {
	my ($kid) = @_;
	return defined(get_sysfs($kid));
}

sub read_file {
	my ($file) = @_;
	local (*INPUT, $/);
	open(INPUT, "<", $file) or die $!;
	return <INPUT>;
}

sub write_file {
	my ($file, $string) = @_;
	local *INPUT;
	open(INPUT, ">", $file) or die $!;
	print INPUT $string;
}

sub read_sysfs {
	my ($kid, $attr) = @_;
	my $sysfs = get_sysfs($kid);
	return undef if (!defined($sysfs));
	return read_file("$sysfs/$attr");
}

sub write_sysfs {
	my ($kid, $attr, $string) = @_;
	my $sysfs = get_sysfs($kid);
	return undef if (!defined($sysfs));
	write_file("$sysfs/$attr", $string);
}

sub get_debug_output {
	my ($kid, $debugfs_out) = @_;
	my $update = "ksplice_$kid";
	if (!$debugfs_out) {
		(undef, $debugfs_out) = tempfile('ksplice-debug-XXXXXX', DIR => tmpdir());
	}
	if (runval_raw("grep", "-qFx", "nodev\tdebugfs", "/proc/filesystems") == 0) {
		my $debugfsdir = tempdir('ksplice-debugfs-XXXXXX', TMPDIR => 1);
		runval(qw(mount -t debugfs debugfs), $debugfsdir);
		if (-e "$debugfsdir/$update") {
			copy("$debugfsdir/$update", $debugfs_out);
		}
		runval(qw(umount), $debugfsdir);
		rmdir($debugfsdir);
		if (!$raw_errors) {
			print STDERR "Debugging output saved to $debugfs_out\n";
		}
		return $debugfs_out;
	} elsif ($? >> 8 == 1) {
		if (!$raw_errors) {
			print STDERR "Debugging output can be found with `dmesg`.\n";
		}
		return ();
	} else {
		child_error();
		exit(-1);
	}
}

sub get_stage {
	my ($kid) = @_;
	chomp(my $result = read_sysfs($kid, "stage"));
	return $result;
}

sub get_abort_cause {
	my ($kid) = @_;
	chomp(my $result = read_sysfs($kid, "abort_cause"));
	return $result;
}

sub get_partial {
	my ($kid) = @_;
	chomp(my $result = read_sysfs($kid, "partial"));
	return $result;
}

sub get_conflicts {
	my ($kid) = @_;
	chomp(my $conflicts = read_sysfs($kid, "conflicts"));
	my @conflicts = split('\n', $conflicts);
	my $out = '';
	foreach my $conflict (@conflicts) {
		my ($name, $pid, $symbols) = $conflict =~ /^(.*) (\d+)(?: (.*))?$/;
		next if (!$symbols);
		$out .= "Process $name(pid $pid) is using the following symbols changed by update $kid:\n";
		foreach my $symbol (split ' ', $symbols) {
			$out .= "  $symbol\n";
		}
	}
	return $out;
}

sub get_raw_conflicts {
	my ($kid) = @_;
	my $conflicts = read_sysfs($kid, "conflicts");
	return $conflicts;
}

sub get_patch {
	my ($kid) = @_;
	my $result = read_file("/var/run/ksplice/updates/$kid/patch");
	return $result;
}

sub get_short_description {
	my ($kid) = @_;
	open(INPUT, "<", "/var/run/ksplice/updates/$kid/description") or return undef;
	my $result = <INPUT>;
	close(INPUT);
	return $result;
}

sub set_stage {
	my ($kid, $string) = @_;
	write_sysfs($kid, "stage", "$string\n");
}

sub set_debug_level {
	my ($kid, $string) = @_;
	write_sysfs($kid, "debug", "$string\n");
}

sub set_partial {
	my ($kid, $string) = @_;
	write_sysfs($kid, "partial", "$string\n");
}

sub print_abort_error {
	my ($kid, %errors) = @_;
	my $error = get_abort_cause($kid);

	print_abort_code($error, %errors);
	if ($error eq 'code_busy') {
		if($raw_errors) {
			print STDERR get_raw_conflicts($kid);
		} else {
			print STDERR get_conflicts($kid);
		}
	}
	$printed_abort_code = 1;
}

sub print_abort_code {
	my ($error, %errors) = @_;
	if($raw_errors) {
		print STDERR "$error\n";
	} else {
		$error = "UNKNOWN" if (!exists $errors{$error});
		print STDERR "\n$errors{$error}\n";
	}
	$printed_abort_code = 1;
}

sub refcount {
	my ($module) = @_;
	$module =~ s/-/_/g;
	foreach(split(/\n/, runstr("cat /proc/modules"))) {
		if (m/^(\S+)\s+[0-9]+\s+([0-9])+\s/) {
			return $2 if ($1 eq $module);
		}
	}
	return -1;
}

END {
	$Verbose::level = 0;
	chdir("/");
}

1;