/**
* Constructor
*/
function __construct($name, $timeoutms = 5000)
{
if (!function_exists('shm_has_var')) {
throw new BaseException("No mutex support on this platform");
}
$this->_lockname = $name;
// Block until lock can be acquired
if (Mutex::$instance == 0) {
Console::debug("Creating mutex manager");
Mutex::$resource = shm_attach(Mutex::SHM_KEY);
if (!shm_has_var(Mutex::$resource, Mutex::SHM_LOCKS)) {
shm_put_var(Mutex::$resource, Mutex::SHM_LOCKS, array());
}
}
$this->enterCriticalSection();
Console::debug("Waiting for lock %s", $this->_lockname);
$t = new timer(true);
while (true) {
$ls = shm_get_var(Mutex::$resource, Mutex::SHM_LOCKS);
if (!isset($ls[$name])) {
break;
}
usleep(100000);
if ($t->getElapsed() > $timeoutms / 1000) {
$this->exitCriticalSection();
throw new MutexException("Timed out waiting for lock");
}
}
Console::debug("Acquiring lock %s", $this->_lockname);
$ls = shm_get_var(Mutex::$resource, Mutex::SHM_LOCKS);
$ls[$name] = true;
shm_put_var(Mutex::$resource, Mutex::SHM_LOCKS, $ls);
Mutex::$instance++;
$this->_lockstate = true;
$this->exitCriticalSection();
}