gnugk_wrapper.pl

H.323网守实现

# output: none
sub killGnugk
{
	my $pid = shift;
	return if ($pid <= 0);
		
	print "  Killing gnugk... " if ($debug);
	my $nKilledProc = kill ('KILL', $pid);
	print "  killed $nKilledProc process(es)\n" if ($debug);
};



# adds leading zeros
# input: (int) number, (int) necessary length
# output: (string) number with leading zeros
sub addLeadingZeros
{
	my ($number, $length) = @_;
	my $ret;

	return $number if (length($number) >= $length);
	my $zeros = "0" x $length;

	return substr($zeros.$number, -$length);
};



# check directory if it exists, is a directory and is writeable
# create new directory if neccessary or die
# die if file exists and is not a directory or writeable
# input: (string) directory path
# output: (int) 1 - is ok; 0 - failure
sub checkDir
{
	my $dirName = shift;
	return 0 if ($dirName eq '');
	
	# check if exists, create if not exist
	if (!(-e $dirName))
	{
		print "$dirName direcotory doesn't exist. Creating...\n";
		if (system ("mkdir -p '$dirName'") != 0)
		{
			print "Can not make directory $dirName\n  $!";
			return 0;
		};
	};
	# check if it is directory, writeable and executeable
	if (!(-w $dirName) || !(-d $dirName) || !(-x $dirName))
	{
		print "$dirName not writeable, executeable or is not directory at all";
		return 0;
	};
	return 1;
};




### main ###

# check global variables
if ($gnugk eq '')
{
	die "No path to gnugk executeable set. Exiting...";
};
if (!(-x $gnugk))
{
	die "Gnugk executeable $gnugk not found or not executeable. Exiting";
};
if ($statusPortCheckInterval <= 0)
{
	print "Status port check interval ivalid: $statusPortCheckInterval\n";
	print "  Setting to default: 60 sec.\n";
	$statusPortCheckInterval = 60;
};
if ($socketTimeout <= 0)
{
	print "Socket timeout value invalid: $socketTimeout\n";
	print "  Setting to default: 10 sec.\n";
	$socketTimeout = 10;
};

# check directories
die "Directory $pidFileDir check unsuccessful" unless checkDir($pidFileDir);
die "Directory $gnugkPidFileDir check unsuccessful" unless checkDir($gnugkPidFileDir);
if ($copyCore)
{
	die "Directory $coreFileDirectory check unsuccessful" unless checkDir($coreFileDirectory);
};
if ($logGnugkRestarts)
{	
	die "Directory $logFileDir check unsuccessful" unless checkDir($logFileDir);
	if (-e $logFile && !(-w $logFile))
	{
		die "Log file $logFile not writeable";
	};
};


# get config values from cmd line
my %conf = getConfStdin(\@ARGV); #get configuration from STDIN
# get home IP address and port (needed for checking if gnugk is frozen)
my ($homeIpAddress, $statusPort) = getConfFromFile(
		$conf{'path_to_gnugk_conf_file'}, $conf{'home_ip_address'}, $conf{'main_section_name'}
	);

# check gnugk home IP address and port
if ((!$homeIpAddress || !$statusPort) && $checkStatusPort)
{
	die "Can not detect gnugk home IP address and port\n";
};


### FORK ###
# create child process and exit from parent process
# run in background as a daemon
my $mainProcId = 0;
if ($runInBackground)
{
	print "Daemonizing...\n";
	exit if ($mainProcId = fork());
}
else
{
	$mainProcId = $$;
};

#print "Main process pid after forking: $mainProcId\n";

# create pid file, clear old one if exists
my $pidFile = "$pidFileDir/gnugk_wrapper_$homeIpAddress.pid";
if (!writePidFile($pidFile, ""))
{
	# set $pidFile to empty string to avoid trying to write to the file if
	#   this attempt failed
	$pidFile = "";
};

# set path to gnugk pid file
my $gnugkPidFile = "$gnugkPidFileDir/gnugk_$homeIpAddress.pid";

# get gnugk execution string (command that executes gnugk)
# concatenate all script arguments into one string
my $argvStr = "";
foreach (@ARGV)
{
	$argvStr .= "$_ ";
};
# cut trailing space
$argvStr =~ s/ $//;
my $gnugkExecStr = "$gnugk $argvStr --pid $gnugkPidFile > /dev/null 2>&1";


### FORK ###
# create child process which will have to run gnugk
# the other one will check if gnugk is ok
my $secondaryProcId = 0;
$secondaryProcId = fork();

# secondary proccess		
# run gnugk in child process
if ($secondaryProcId == 0)
{	
	# write current process pid to pid file
	writePidFile($pidFile, $$);
	
	# neverending loop for executing gnugk
	my $i = 0;
	my $gnugkExitCode = 0;
	while(1)
	{
		$i++;
		print "---\n\n" if ($debug);
		print "Executing gnugk (attempt: $i):\n" if ($debug);
		print "  $gnugkExecStr\n" if ($debug);
		$gnugkExitCode = system("$gnugkExecStr");
		print "  gnugk exited with code $gnugkExitCode\n. Restarting gnugk process\n" if($debug);
		
		# prepare current time
		my $timeNow = localtime->year+1900;
		$timeNow .= addLeadingZeros(localtime->mon, 2);
		$timeNow .= addLeadingZeros(localtime->mday, 2);
		$timeNow .= "_";
		$timeNow .= addLeadingZeros(localtime->hour, 2);
		$timeNow .= addLeadingZeros(localtime->min, 2);
		$timeNow .= addLeadingZeros(localtime->sec, 2);
		
		# copy gnugk core to core file directory
		if ($copyCore && -e './gnugk.core')
		{
			
			my $coreName = "gnugk_$timeNow.core";
			print "  Copying ./gnugk.core to $coreFileDirectory/$coreName\n";
			system ("cp ./gnugk.core $coreFileDirectory/$coreName");
		};
		
		# log restarting event to log file
		if ($logGnugkRestarts)
		{
			# open file
			eval
			{
				open (LOGFILE, ">>$logFile") or die "Error: can not open log file $logFile\n  $!";
			};
			# print error
			if ($@)
			{
				print $@ if ($debug);
			}
			# print message to log file
			else
			{
				print LOGFILE "[$timeNow] $homeIpAddress gnugk exited with code $gnugkExitCode\n";
				close (LOGFILE);
			};
		};
	};
	
}
# primary process
# check gnugk if it is ok
# kill gnugk proccess if needed
else
{	
	# write current process pid to pid file
	writePidFile($pidFile, $$);
	
	# Exit if status port checking disabled
	if (!$checkStatusPort)
	{
		print "Status port checking disabled\n" if ($debug);
		exit(0);
	};
	
	# neverending loop for checking status port
	my $sockMsg = ""; # output from socket
	my $sock = undef; # socket
	my $goodChars = 'A-Za-z0-9_;'; # character that are allowed to appear as normal status port output
	while (1)
	{
		# set variables to defaults
		$sock = undef;
		$sockMsg = "";
		
		sleep ($statusPortCheckInterval);
		print "---\n\n" if ($debug);
		print "Checking gnugk status port\n" if($debug);
		
		# open socket
		$sock = new Net::Telnet (
					Timeout		=> $socketTimeout,
					Host		=> $homeIpAddress,
					Port		=> $statusPort,
#					Prompt		=> '',
					Errmode		=> 'return',
					Telnetmode	=> 0,
				);
		$sock->open();
		
		# check socket
		if ($sock && !$sock->errmsg())
		{	
			print "  Socket opened successfully...\n" if ($debug);
			
			#read data from sock
			$sockMsg = "";
			my $blankLines = 0;
			# read from socket until buffer is empty, timeout occured or there is semicolon only in the line
			while (!$sock->eof() && !$sock->timed_out)
			{
				my $msg = $sock->getline(); # get one line
				$msg =~ s/^[^$goodChars]+|[^$goodChars]+$//; # cut out all non-good characters
				$sockMsg .= $msg;
				$blankLines++ if ($msg eq '' &&  $sockCheckMaxBlankLines); # increase number of blank lines if line from status port is blank
				last if ($blankLines >= $sockMaxBlankLines &&  $sockCheckMaxBlankLines); # break loop if max number of blank lines received
				last if ($msg eq ';'); # consider that message is received if there is semicolon only in current line
			};
			print "  Got from socket:\n" if ($debug);
			print "    $sockMsg\n"	if ($debug);
			
			# If socked timed out kill gnugk and skip all other checks
			if ($sock->timed_out)
			{
				print "  Socket timed out\n" if ($debug);
				$sock->close();
				killGnugk(getGnugkPid($gnugkPidFile));
				next;
			};
			# If access forbidden kill gnugk and skip all other checks
			if ($sockMsg =~ m/Access forbidden/i)
			{
				print "  Access forbidden to gnugk status port\n" if ($debug);
				$sock->close();
				killGnugk(getGnugkPid($gnugkPidFile));
				next;
			};
			# If no data received from gnugk kill gnugk and skip all other checks
			if ($sockMsg eq '')
			{
				print "  No message received from gnugk status port\n" if ($debug);
				$sock->close();
				killGnugk(getGnugkPid($gnugkPidFile));
				next;
			};
			# If max numbewr of blank lines received kill gnugk and skip all other checks
			if ($blankLines >= $sockMaxBlankLines &&  $sockCheckMaxBlankLines)
			{
				print "  Maximum number of blank lines from status port received\n" if ($debug);
				$sock->close();
				killGnugk(getGnugkPid($gnugkPidFile));
				next;
			};
			
			# set gnugk status port trace level to 0 to enable only direct responses to commands
			print "  Setting status port trace level to 0...\n" if ($debug);
			if(!$sock->put("trace 0\r\n"))
			{
				print "  Trace level adjusting unsuccessful\n" if ($debug);
				$sock->close();
				killGnugk(getGnugkPid($gnugkPidFile));
				next;
			};
			print "    Trace level set: ".$sock->getline() if ($debug);
			
			# clear sockets input buffer to be sure that no unwanted input is stored in it
			$sock->buffer_empty;
			
			# try to get version string from gnugk
			# kill gnugk if unsuccessful
			print "  Trying to get gnugk version from status port...\n" if($debug);
			if (!$sock->put("Version\r\n"))
			{
				print "  Sending \"Version\" request unsuccessful\n" if ($debug);
				$sock->close();
				killGnugk(getGnugkPid($gnugkPidFile));
				next;
			};
			
			#read data from sock
			$sockMsg = "";
			$blankLines = 0;
			# read from socket until buffer is empty, timeout occured or there is semicolon only in the line
			while (!$sock->eof() && !$sock->timed_out)
			{
				my $msg = $sock->getline(); # get one line
				$msg =~ s/^[^$goodChars]+|[^$goodChars]+$//; # cut out all non-good characters
				$sockMsg .= $msg;
				$blankLines++ if ($msg eq '' &&  $sockCheckMaxBlankLines); # increase number of blank lines if line from status port is blank
				last if ($blankLines >= $sockMaxBlankLines &&  $sockCheckMaxBlankLines); # break loop if max number of blank lines received
				last if ($msg eq ';'); # consider that message is received if there is semicolon only in current line
			};	
			
			print "  Got from socket:\n" if ($debug);
			print "    $sockMsg\n"	if ($debug);
			
			# If socked timed out kill gnugk and skip all other checks
			if ($sock->timed_out)
			{
				print "  Socket timed out\n" if ($debug);
				$sock->close();
				killGnugk(getGnugkPid($gnugkPidFile));
				next;
			};
			# If no data received from gnugk kill gnugk and skip all other checks
			if ($sockMsg eq '')
			{
				print "  No message received from gnugk status port\n" if ($debug);
				$sock->close();
				killGnugk(getGnugkPid($gnugkPidFile));
				next;
			};
			# If max numbewr of blank lines received kill gnugk and skip all other checks
			if ($blankLines >= $sockMaxBlankLines &&  $sockCheckMaxBlankLines)
			{
				print "  Maximum number of blank lines from status port received\n" if ($debug);
				$sock->close();
				killGnugk(getGnugkPid($gnugkPidFile));
				next;
			};
			
			$sock->close();
		}
		# report error and killgnugk
		else
		{
			print "  Could not create socket\n    $!\n" if ($debug);
			killGnugk(getGnugkPid($gnugkPidFile));
		};
	};
};