[RFC] Improve compatibility with legacy versions

.travis.yml

@@ -1,6 +1,7 @@
 language: php
 
 php:
+# - 5.3 # requires old distro, see below
   - 5.4
   - 5.5
   - 5.6
@@ -13,6 +14,9 @@ php:
 dist: trusty
 
 matrix:
+  include:
+    - php: 5.3
+      dist: precise
   allow_failures:
     - php: hhvm
 

README.md

@@ -158,7 +158,7 @@ A `stream_select()` based event loop.
 This uses the [`stream_select()`](http://php.net/manual/en/function.stream-select.php)
 function and is the only implementation which works out of the box with PHP.
 
-This event loop works out of the box on PHP 5.4 through PHP 7+ and HHVM.
+This event loop works out of the box on PHP 5.3 through PHP 7+ and HHVM.
 This means that no installation is required and this library works on all
 platforms and supported PHP versions.
 Accordingly, the [`Factory`](#factory) will use this event loop by default if
@@ -574,7 +574,7 @@ $ composer require react/event-loop
 ```
 
 This project aims to run on any platform and thus does not require any PHP
-extensions and supports running on legacy PHP 5.4 through current PHP 7+ and
+extensions and supports running on legacy PHP 5.3 through current PHP 7+ and
 HHVM.
 It's *highly recommended to use PHP 7+* for this project.
 

composer.json

@@ -4,7 +4,7 @@
     "keywords": ["event-loop", "asynchronous"],
     "license": "MIT",
     "require": {
-        "php": ">=5.4.0"
+        "php": ">=5.3.0"
     },
     "require-dev": {
         "phpunit/phpunit": "~4.8.35 || ^5.7 || ^6.4"

src/ExtEventLoop.php

@@ -26,15 +26,15 @@ final class ExtEventLoop implements LoopInterface
     private $timerCallback;
     private $timerEvents;
     private $streamCallback;
-    private $readEvents = [];
-    private $writeEvents = [];
-    private $readListeners = [];
-    private $writeListeners = [];
-    private $readRefs = [];
-    private $writeRefs = [];
+    private $readEvents = array();
+    private $writeEvents = array();
+    private $readListeners = array();
+    private $writeListeners = array();
+    private $readRefs = array();
+    private $writeRefs = array();
     private $running;
     private $signals;
-    private $signalEvents = [];
+    private $signalEvents = array();
 
     public function __construct(EventBaseConfig $config = null)
     {
@@ -215,10 +215,11 @@ private function scheduleTimer(TimerInterface $timer)
      */
     private function createTimerCallback()
     {
-        $this->timerCallback = function ($_, $__, $timer) {
+        $timers = $this->timerEvents;
+        $this->timerCallback = function ($_, $__, $timer) use ($timers) {
             call_user_func($timer->getCallback(), $timer);
 
-            if (!$timer->isPeriodic() && $this->timerEvents->contains($timer)) {
+            if (!$timer->isPeriodic() && $timers->contains($timer)) {
                 $this->cancelTimer($timer);
             }
         };
@@ -233,15 +234,17 @@ private function createTimerCallback()
      */
     private function createStreamCallback()
     {
-        $this->streamCallback = function ($stream, $flags) {
+        $read =& $this->readListeners;
+        $write =& $this->writeListeners;
+        $this->streamCallback = function ($stream, $flags) use (&$read, &$write) {
             $key = (int) $stream;
 
-            if (Event::READ === (Event::READ & $flags) && isset($this->readListeners[$key])) {
-                call_user_func($this->readListeners[$key], $stream);
+            if (Event::READ === (Event::READ & $flags) && isset($read[$key])) {
+                call_user_func($read[$key], $stream);
             }
 
-            if (Event::WRITE === (Event::WRITE & $flags) && isset($this->writeListeners[$key])) {
-                call_user_func($this->writeListeners[$key], $stream);
+            if (Event::WRITE === (Event::WRITE & $flags) && isset($write[$key])) {
+                call_user_func($write[$key], $stream);
             }
         };
     }

src/ExtLibevLoop.php

@@ -28,11 +28,11 @@ final class ExtLibevLoop implements LoopInterface
     private $loop;
     private $futureTickQueue;
     private $timerEvents;
-    private $readEvents = [];
-    private $writeEvents = [];
+    private $readEvents = array();
+    private $writeEvents = array();
     private $running;
     private $signals;
-    private $signalEvents = [];
+    private $signalEvents = array();
 
     public function __construct()
     {
@@ -100,11 +100,13 @@ public function addTimer($interval, $callback)
     {
         $timer = new Timer( $interval, $callback, false);
 
-        $callback = function () use ($timer) {
+        $that = $this;
+        $timers = $this->timerEvents;
+        $callback = function () use ($timer, $timers, $that) {
             call_user_func($timer->getCallback(), $timer);
 
-            if ($this->timerEvents->contains($timer)) {
-                $this->cancelTimer($timer);
+            if ($timers->contains($timer)) {
+                $that->cancelTimer($timer);
             }
         };
 
@@ -148,8 +150,9 @@ public function addSignal($signal, $listener)
         $this->signals->add($signal, $listener);
 
         if (!isset($this->signalEvents[$signal])) {
-            $this->signalEvents[$signal] = new SignalEvent(function () use ($signal) {
-                $this->signals->call($signal);
+            $signals = $this->signals;
+            $this->signalEvents[$signal] = new SignalEvent(function () use ($signals, $signal) {
+                $signals->call($signal);
             }, $signal);
             $this->loop->add($this->signalEvents[$signal]);
         }

src/ExtLibeventLoop.php

@@ -42,13 +42,13 @@ final class ExtLibeventLoop implements LoopInterface
     private $timerCallback;
     private $timerEvents;
     private $streamCallback;
-    private $readEvents = [];
-    private $writeEvents = [];
-    private $readListeners = [];
-    private $writeListeners = [];
+    private $readEvents = array();
+    private $writeEvents = array();
+    private $readListeners = array();
+    private $writeListeners = array();
     private $running;
     private $signals;
-    private $signalEvents = [];
+    private $signalEvents = array();
 
     public function __construct()
     {
@@ -228,24 +228,26 @@ private function scheduleTimer(TimerInterface $timer)
      */
     private function createTimerCallback()
     {
-        $this->timerCallback = function ($_, $__, $timer) {
+        $that = $this;
+        $timers = $this->timerEvents;
+        $this->timerCallback = function ($_, $__, $timer) use ($timers, $that) {
             call_user_func($timer->getCallback(), $timer);
 
             // Timer already cancelled ...
-            if (!$this->timerEvents->contains($timer)) {
+            if (!$timers->contains($timer)) {
                 return;
             }
 
             // Reschedule periodic timers ...
             if ($timer->isPeriodic()) {
                 event_add(
-                    $this->timerEvents[$timer],
-                    $timer->getInterval() * self::MICROSECONDS_PER_SECOND
+                    $timers[$timer],
+                    $timer->getInterval() * ExtLibeventLoop::MICROSECONDS_PER_SECOND
                 );
 
             // Clean-up one shot timers ...
             } else {
-                $this->cancelTimer($timer);
+                $that->cancelTimer($timer);
             }
         };
     }
@@ -259,15 +261,17 @@ private function createTimerCallback()
      */
     private function createStreamCallback()
     {
-        $this->streamCallback = function ($stream, $flags) {
+        $read =& $this->readListeners;
+        $write =& $this->writeListeners;
+        $this->streamCallback = function ($stream, $flags) use (&$read, &$write) {
             $key = (int) $stream;
 
-            if (EV_READ === (EV_READ & $flags) && isset($this->readListeners[$key])) {
-                call_user_func($this->readListeners[$key], $stream);
+            if (EV_READ === (EV_READ & $flags) && isset($read[$key])) {
+                call_user_func($read[$key], $stream);
             }
 
-            if (EV_WRITE === (EV_WRITE & $flags) && isset($this->writeListeners[$key])) {
-                call_user_func($this->writeListeners[$key], $stream);
+            if (EV_WRITE === (EV_WRITE & $flags) && isset($write[$key])) {
+                call_user_func($write[$key], $stream);
             }
         };
     }

src/SignalsHandler.php

@@ -7,12 +7,12 @@
  */
 final class SignalsHandler
 {
-    private $signals = [];
+    private $signals = array();
 
     public function add($signal, $listener)
     {
         if (!isset($this->signals[$signal])) {
-            $this->signals[$signal] = [];
+            $this->signals[$signal] = array();
         }
 
         if (in_array($listener, $this->signals[$signal])) {

src/StreamSelectLoop.php

@@ -56,10 +56,10 @@ final class StreamSelectLoop implements LoopInterface
 
     private $futureTickQueue;
     private $timers;
-    private $readStreams = [];
-    private $readListeners = [];
-    private $writeStreams = [];
-    private $writeListeners = [];
+    private $readStreams = array();
+    private $readListeners = array();
+    private $writeStreams = array();
+    private $writeListeners = array();
     private $running;
     private $pcntl = false;
     private $signals;