onGeneratorError = function($e, $r) { if ($e) { throw $e; } }; } /** * Start the event reactor and assume program flow control * * @param callable $onStart Optional callback to invoke immediately upon reactor start * @throws \Exception Will throw if code executed during the event loop throws * @return void */ public function run(callable $onStart = null) { if ($this->isRunning) { return; } $this->isRunning = true; if ($onStart) { $this->immediately($onStart); } $this->enableAlarms(); while ($this->isRunning || $this->immediates) { $this->tick(); } } private function enableAlarms() { $now = microtime(true); $enabled = 0; foreach ($this->alarms as $watcherId => $alarmStruct) { $nextExecution = $alarmStruct[1]; if (!$nextExecution) { $enabled++; $delay = $alarmStruct[2]; $nextExecution = $now + $delay; $alarmStruct[1] = $nextExecution; $this->alarms[$watcherId] = $alarmStruct; $this->alarmOrder[$watcherId] = $nextExecution; } } } /** * Stop the event reactor * * @return void */ public function stop() { $this->isRunning = false; } /** * Execute a single event loop iteration * * @throws \Exception will throw any uncaught exception encountered during the loop iteration * @return void */ public function tick() { if (!$this->isRunning) { $this->enableAlarms(); } if ($immediates = $this->immediates) { $this->immediates = []; foreach ($immediates as $watcherId => $callback) { $result = $callback($this, $watcherId); if ($result instanceof \Generator) { resolve($this, $result)->when($this->onGeneratorError); } } } if ($this->immediates) { $timeToNextAlarm = 0; } elseif ($this->alarmOrder) { $timeToNextAlarm = round(min($this->alarmOrder) - microtime(true), 4); } else { $timeToNextAlarm = 1; } if ($this->readStreams || $this->writeStreams) { $this->selectActionableStreams($timeToNextAlarm); } elseif (!$this->alarmOrder) { $this->stop(); } elseif ($timeToNextAlarm > 0) { usleep($timeToNextAlarm * self::$MICROSECOND); } if ($this->alarmOrder) { $this->executeAlarms(); } } private function selectActionableStreams($timeout) { $r = $this->readStreams; $w = $this->writeStreams; $e = null; if ($timeout <= 0) { $sec = 0; $usec = 0; } else { $sec = floor($timeout); $usec = ($timeout - $sec) * self::$MICROSECOND; } if (@stream_select($r, $w, $e, $sec, $usec)) { foreach ($r as $readableStream) { $streamId = (int) $readableStream; foreach ($this->readCallbacks[$streamId] as $watcherId => $callback) { $result = $callback($this, $watcherId, $readableStream); if ($result instanceof \Generator) { resolve($this, $result)->when($this->onGeneratorError); } } } foreach ($w as $writableStream) { $streamId = (int) $writableStream; foreach ($this->writeCallbacks[$streamId] as $watcherId => $callback) { $result = $callback($this, $watcherId, $writableStream); if ($result instanceof \Generator) { resolve($this, $result)->when($this->onGeneratorError); } } } } } private function executeAlarms() { $now = microtime(true); asort($this->alarmOrder); foreach ($this->alarmOrder as $watcherId => $executionCutoff) { if ($executionCutoff > $now) { break; } list($callback, $nextExecution, $interval, $isRepeating) = $this->alarms[$watcherId]; if ($isRepeating) { $nextExecution += $interval; $this->alarms[$watcherId] = [$callback, $nextExecution, $interval, $isRepeating]; $this->alarmOrder[$watcherId] = $nextExecution; } else { unset( $this->alarms[$watcherId], $this->alarmOrder[$watcherId] ); } $result = $callback($this, $watcherId); if ($result instanceof \Generator) { resolve($this, $result)->when($this->onGeneratorError); } } } /** * Schedule an event to trigger once at the specified time * * @param callable $callback Any valid PHP callable * @param mixed[int|string] $unixTimeOrStr A future unix timestamp or string parsable by strtotime() * @throws \InvalidArgumentException On invalid future time * @return string Returns a unique watcher ID */ public function at(callable $callback, $unixTimeOrStr) { $now = time(); if (is_int($unixTimeOrStr) && $unixTimeOrStr > $now) { $secondsUntil = ($unixTimeOrStr - $now); } elseif (($executeAt = @strtotime($unixTimeOrStr)) && $executeAt > $now) { $secondsUntil = ($executeAt - $now); } else { throw new \InvalidArgumentException( 'Unix timestamp or future time string (parsable by strtotime()) required' ); } $msDelay = $secondsUntil * $this->resolution; return $this->once($callback, $msDelay); } /** * Schedule a callback for immediate invocation in the next event loop iteration * * @param callable $callback Any valid PHP callable * @return string Returns a unique watcher ID */ public function immediately(callable $callback) { $watcherId = (string) $this->lastWatcherId++; $this->immediates[$watcherId] = $callback; return $watcherId; } /** * Schedule a callback to execute once * * @param callable $callback Any valid PHP callable * @param int $msDelay The delay in milliseconds before the callback will trigger (may be zero) * @return string Returns a unique watcher ID */ public function once(callable $callback, $msDelay) { return $this->scheduleAlarm($callback, $msDelay, $isRepeating = false); } /** * Schedule a recurring callback to execute every $interval seconds until cancelled * * @param callable $callback Any valid PHP callable * @param int $msDelay The interval in milliseconds between callback invocations * @return string Returns a unique watcher ID */ public function repeat(callable $callback, $msDelay) { return $this->scheduleAlarm($callback, $msDelay, $isRepeating = true); } private function scheduleAlarm($callback, $msDelay, $isRepeating) { $watcherId = (string) $this->lastWatcherId++; $msDelay = round(($msDelay / $this->resolution), 3); if ($this->isRunning) { $nextExecution = (microtime(true) + $msDelay); $this->alarmOrder[$watcherId] = $nextExecution; } else { $nextExecution = null; } $alarmStruct = [$callback, $nextExecution, $msDelay, $isRepeating]; $this->alarms[$watcherId] = $alarmStruct; return $watcherId; } /** * Watch a stream resource for IO readable data and trigger the callback when actionable * * @param resource $stream A stream resource to watch for readable data * @param callable $callback Any valid PHP callable * @param bool $enableNow Should the watcher be enabled now or held for later use? * @return string Returns a unique watcher ID */ public function onReadable($stream, callable $callback, $enableNow = true) { $watcherId = (string) $this->lastWatcherId++; if ($enableNow) { $streamId = (int) $stream; $this->readStreams[$streamId] = $stream; $this->readCallbacks[$streamId][$watcherId] = $callback; $this->watcherIdReadStreamIdMap[$watcherId] = $streamId; } else { $this->disabledWatchers[$watcherId] = [self::$DISABLED_READ, [$stream, $callback]]; } return $watcherId; } /** * Watch a stream resource to become writable and trigger the callback when actionable * * @param resource $stream A stream resource to watch for writability * @param callable $callback Any valid PHP callable * @param bool $enableNow Should the watcher be enabled now or held for later use? * @return string Returns a unique watcher ID */ public function onWritable($stream, callable $callback, $enableNow = true) { $watcherId = (string) $this->lastWatcherId++; if ($enableNow) { $streamId = (int) $stream; $this->writeStreams[$streamId] = $stream; $this->writeCallbacks[$streamId][$watcherId] = $callback; $this->watcherIdWriteStreamIdMap[$watcherId] = $streamId; } else { $this->disabledWatchers[$watcherId] = [self::$DISABLED_WRITE, [$stream, $callback]]; } return $watcherId; } /** * Cancel an existing watcher * * @param string $watcherId * @return void */ public function cancel($watcherId) { if (isset($this->alarms[$watcherId])) { unset( $this->alarms[$watcherId], $this->alarmOrder[$watcherId] ); } elseif (isset($this->watcherIdReadStreamIdMap[$watcherId])) { $this->cancelReadWatcher($watcherId); } elseif (isset($this->watcherIdWriteStreamIdMap[$watcherId])) { $this->cancelWriteWatcher($watcherId); } elseif (isset($this->disabledWatchers[$watcherId])) { unset($this->disabledWatchers[$watcherId]); } elseif (isset($this->immediates[$watcherId])) { unset($this->immediates[$watcherId]); } } private function cancelReadWatcher($watcherId) { $streamId = $this->watcherIdReadStreamIdMap[$watcherId]; unset( $this->readCallbacks[$streamId][$watcherId], $this->watcherIdReadStreamIdMap[$watcherId], $this->disabledWatchers[$watcherId] ); if (empty($this->readCallbacks[$streamId])) { unset($this->readStreams[$streamId]); } } private function cancelWriteWatcher($watcherId) { $streamId = $this->watcherIdWriteStreamIdMap[$watcherId]; unset( $this->writeCallbacks[$streamId][$watcherId], $this->watcherIdWriteStreamIdMap[$watcherId], $this->disabledWatchers[$watcherId] ); if (empty($this->writeCallbacks[$streamId])) { unset($this->writeStreams[$streamId]); } } /** * Enable a disabled timer/stream watcher * * @param string $watcherId * @return void */ public function enable($watcherId) { if (!isset($this->disabledWatchers[$watcherId])) { return; } list($type, $watcherStruct) = $this->disabledWatchers[$watcherId]; unset($this->disabledWatchers[$watcherId]); switch ($type) { case self::$DISABLED_ALARM: if (!$nextExecution = $watcherStruct[1]) { $nextExecution = microtime(true) + $watcherStruct[2]; $watcherStruct[1] = $nextExecution; } $this->alarms[$watcherId] = $watcherStruct; $this->alarmOrder[$watcherId] = $nextExecution; break; case self::$DISABLED_READ: list($stream, $callback) = $watcherStruct; $streamId = (int) $stream; $this->readCallbacks[$streamId][$watcherId] = $callback; $this->watcherIdReadStreamIdMap[$watcherId] = $streamId; $this->readStreams[$streamId] = $stream; break; case self::$DISABLED_WRITE: list($stream, $callback) = $watcherStruct; $streamId = (int) $stream; $this->writeCallbacks[$streamId][$watcherId] = $callback; $this->watcherIdWriteStreamIdMap[$watcherId] = $streamId; $this->writeStreams[$streamId] = $stream; break; case self::$DISABLED_IMMEDIATE: $this->immediates[$watcherId] = $watcherStruct; break; } } /** * Temporarily disable (but don't cancel) an existing timer/stream watcher * * @param string $watcherId * @return void */ public function disable($watcherId) { if (isset($this->alarms[$watcherId])) { $alarmStruct = $this->alarms[$watcherId]; $this->disabledWatchers[$watcherId] = [self::$DISABLED_ALARM, $alarmStruct]; unset( $this->alarms[$watcherId], $this->alarmOrder[$watcherId] ); } elseif (isset($this->watcherIdReadStreamIdMap[$watcherId])) { $streamId = $this->watcherIdReadStreamIdMap[$watcherId]; $stream = $this->readStreams[$streamId]; $callback = $this->readCallbacks[$streamId][$watcherId]; unset( $this->readCallbacks[$streamId][$watcherId], $this->watcherIdReadStreamIdMap[$watcherId] ); if (empty($this->readCallbacks[$streamId])) { unset($this->readStreams[$streamId]); } $this->disabledWatchers[$watcherId] = [self::$DISABLED_READ, [$stream, $callback]]; } elseif (isset($this->watcherIdWriteStreamIdMap[$watcherId])) { $streamId = $this->watcherIdWriteStreamIdMap[$watcherId]; $stream = $this->writeStreams[$streamId]; $callback = $this->writeCallbacks[$streamId][$watcherId]; unset( $this->writeCallbacks[$streamId][$watcherId], $this->watcherIdWriteStreamIdMap[$watcherId] ); if (empty($this->writeCallbacks[$streamId])) { unset($this->writeStreams[$streamId]); } $this->disabledWatchers[$watcherId] = [self::$DISABLED_WRITE, [$stream, $callback]]; } elseif (isset($this->immediates[$watcherId])) { $this->disabledWatchers[$watcherId] = [self::$DISABLED_IMMEDIATE, $this->immediates[$watcherId]]; unset($this->immediates[$watcherId]); } } }