/**
* Determine the nature of the environment and how we will perform the
* mutex.
*
* @param mixed $lockParam
*/
public function __construct($lockParam)
{
if (self::$_useSysV === null) {
PFXUtils::validateSettings(self::$_SETTINGS, self::$_SETTING_TESTS);
if (MUTEX_DEBUG_LOG_FILE) {
self::$_log = fopen(MUTEX_DEBUG_LOG_FILE, 'w');
}
$osType = strtolower(substr(PHP_OS, 0, 3));
// Cygwin has the SysV functions but they don't actually work
if (!function_exists('sem_acquire') || $osType == 'cyg') {
self::$_useSysV = false;
self::$_lockFileBase = sys_get_temp_dir() . DIRECTORY_SEPARATOR . 'mutex.{LOCK_ID}.tmp';
} else {
self::$_useSysV = true;
}
self::$_activeResources = new SplQueue();
}
if (self::$_log) {
$this->_mutexID = uniqid();
$trace = debug_backtrace();
self::_log(sprintf('Mutex %s constructed in %s (%s)', $this->_mutexID, $trace[0]['file'], $trace[0]['line']));
}
// If we were passed an object instance, get its class name
if (is_object($lockParam)) {
$lockParam = get_class($lockParam);
}
if (filter_var($lockParam, FILTER_VALIDATE_INT) !== false) {
$lockMethod = self::LOCK_METHOD_MANUAL;
$lockID = (int) $lockParam;
} else {
$lockMethod = self::LOCK_METHOD_AUTO;
$lockID = crc32($lockParam);
}
if (isset(self::$_REGISTERED_KEY_LOCK_METHODS[$lockID]) && self::$_REGISTERED_KEY_LOCK_METHODS[$lockID] != $lockMethod) {
throw new MutexException('The mutex lock parameter "' . $lockParam . '" conflicts ' . 'with an existing mutex.');
}
self::$_REGISTERED_KEY_LOCK_METHODS[$lockID] = $lockMethod;
$this->_lockID = $lockID;
if (self::$_useSysV) {
$this->_lockResource = sem_get($this->_lockID, 1, 0666, 1);
} else {
$lockFile = str_replace('{LOCK_ID}', $this->_lockID, self::$_lockFileBase);
$this->_lockResource = fopen($lockFile, 'a+b');
// I'm not supporting the cleanup operation for real sempahores
self::$_activeResources->enqueue($this->_lockResource);
self::$_activeResources->enqueue($lockFile);
}
if (!$this->_lockResource) {
throw new MutexException('Failed to obtain lock resource for mutex.');
}
}
