Implement monotonic timer using PHP 7.3's hrtime()

amphp · Dec 10, 2018 · 5622edb · 5622edb
1 parent 5889f4e
commit 5622edb
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Showing 4 changed files with 29 additions and 11 deletions.
diff --git a/lib/Internal/functions.php b/lib/Internal/functions.php
@@ -51,3 +51,18 @@ function createTypeError(array $expected, $given): \TypeError
 
     return new \TypeError("{$expectedType}; {$givenType} given");
 }
+
+/**
+ * Returns the current time relative to an arbitrary point in time.
+ *
+ * @return int Time in milliseconds.
+ */
+function getCurrentTime(): int
+{
+    if (\PHP_VERSION_ID >= 70300) {
+        list($seconds, $nanoseconds) = \hrtime(false);
+        return $seconds * 1000 + $nanoseconds / 1000000;
+    }
+
+    return (int) (\microtime(true) * 1000);
+}
diff --git a/lib/Loop/EvDriver.php b/lib/Loop/EvDriver.php
@@ -5,6 +5,7 @@
 use Amp\Coroutine;
 use Amp\Promise;
 use React\Promise\PromiseInterface as ReactPromise;
+use function Amp\Internal\getCurrentTime;
 use function Amp\Promise\rethrow;
 
 class EvDriver extends Driver
@@ -36,13 +37,13 @@ class EvDriver extends Driver
     /** @var bool */
     private $nowUpdateNeeded = false;
 
-    /** @var int Loop time offset from microtime() */
+    /** @var int Loop time offset */
     private $nowOffset;
 
     public function __construct()
     {
         $this->handle = new \EvLoop;
-        $this->nowOffset = (int) (\microtime(true) * self::MILLISEC_PER_SEC);
+        $this->nowOffset = getCurrentTime();
         $this->now = \random_int(0, $this->nowOffset);
         $this->nowOffset -= $this->now;
 
@@ -203,7 +204,7 @@ public function stop()
     public function now(): int
     {
         if ($this->nowUpdateNeeded) {
-            $this->now = (int) (\microtime(true) * self::MILLISEC_PER_SEC) - $this->nowOffset;
+            $this->now = getCurrentTime() - $this->nowOffset;
             $this->nowUpdateNeeded = false;
         }
 

diff --git a/lib/Loop/EventDriver.php b/lib/Loop/EventDriver.php
@@ -5,6 +5,7 @@
 use Amp\Coroutine;
 use Amp\Promise;
 use React\Promise\PromiseInterface as ReactPromise;
+use function Amp\Internal\getCurrentTime;
 use function Amp\Promise\rethrow;
 
 class EventDriver extends Driver
@@ -36,13 +37,13 @@ class EventDriver extends Driver
     /** @var int Internal timestamp for now. */
     private $now;
 
-    /** @var int Loop time offset from microtime() */
+    /** @var int Loop time offset */
     private $nowOffset;
 
     public function __construct()
     {
         $this->handle = new \EventBase;
-        $this->nowOffset = (int) (\microtime(true) * self::MILLISEC_PER_SEC);
+        $this->nowOffset = getCurrentTime();
         $this->now = \random_int(0, $this->nowOffset);
         $this->nowOffset -= $this->now;
 
@@ -205,7 +206,7 @@ public function stop()
     public function now(): int
     {
         if ($this->nowUpdateNeeded) {
-            $this->now = (int) (\microtime(true) * self::MILLISEC_PER_SEC) - $this->nowOffset;
+            $this->now = getCurrentTime() - $this->nowOffset;
             $this->nowUpdateNeeded = false;
         }
 
@@ -234,7 +235,7 @@ protected function dispatch(bool $blocking)
      */
     protected function activate(array $watchers)
     {
-        $now = (int) (\microtime(true) * self::MILLISEC_PER_SEC) - $this->nowOffset;
+        $now = getCurrentTime() - $this->nowOffset;
 
         foreach ($watchers as $watcher) {
             if (!isset($this->events[$id = $watcher->id])) {

diff --git a/lib/Loop/NativeDriver.php b/lib/Loop/NativeDriver.php
@@ -5,6 +5,7 @@
 use Amp\Coroutine;
 use Amp\Promise;
 use React\Promise\PromiseInterface as ReactPromise;
+use function Amp\Internal\getCurrentTime;
 use function Amp\Promise\rethrow;
 
 class NativeDriver extends Driver
@@ -36,7 +37,7 @@ class NativeDriver extends Driver
     /** @var int Internal timestamp for now. */
     private $now;
 
-    /** @var int Loop time offset from microtime() */
+    /** @var int Loop time offset */
     private $nowOffset;
 
     /** @var bool */
@@ -46,7 +47,7 @@ public function __construct()
     {
         $this->timerQueue = new \SplPriorityQueue();
         $this->signalHandling = \extension_loaded("pcntl");
-        $this->nowOffset = (int) (\microtime(true) * self::MILLISEC_PER_SEC);
+        $this->nowOffset = getCurrentTime();
         $this->now = \random_int(0, $this->nowOffset);
         $this->nowOffset -= $this->now;
     }
@@ -71,7 +72,7 @@ public function onSignal(int $signo, callable $callback, $data = null): string
     public function now(): int
     {
         if ($this->nowUpdateNeeded) {
-            $this->now = (int) (\microtime(true) * self::MILLISEC_PER_SEC) - $this->nowOffset;
+            $this->now = getCurrentTime() - $this->nowOffset;
             $this->nowUpdateNeeded = false;
         }
 
@@ -275,7 +276,7 @@ private function getTimeout()
                 continue;
             }
 
-            $expiration -= (int) (\microtime(true) * self::MILLISEC_PER_SEC);
+            $expiration -= getCurrentTime();
 
             if ($expiration < 0) {
                 return 0;