1<?php 2 3class EventLoop 4{ 5 private string $nextId = 'a'; 6 private array $deferCallbacks = []; 7 private array $read = []; 8 private array $streamCallbacks = []; 9 10 public function run(): void 11 { 12 while (!empty($this->deferCallbacks) || !empty($this->read)) { 13 $defers = $this->deferCallbacks; 14 $this->deferCallbacks = []; 15 foreach ($defers as $id => $defer) { 16 $defer(); 17 } 18 19 $this->select($this->read); 20 } 21 } 22 23 private function select(array $read): void 24 { 25 $timeout = empty($this->deferCallbacks) ? null : 0; 26 if (!stream_select($read, $write, $except, $timeout, $timeout)) { 27 return; 28 } 29 30 foreach ($read as $id => $resource) { 31 $callback = $this->streamCallbacks[$id]; 32 unset($this->read[$id], $this->streamCallbacks[$id]); 33 $callback($resource); 34 } 35 } 36 public function defer(callable $callback): void 37 { 38 $id = $this->nextId++; 39 $this->deferCallbacks[$id] = $callback; 40 } 41 42 public function read($resource, callable $callback): void 43 { 44 $id = $this->nextId++; 45 $this->read[$id] = $resource; 46 $this->streamCallbacks[$id] = $callback; 47 } 48} 49 50[$read, $write] = stream_socket_pair( 51 stripos(PHP_OS, 'win') === 0 ? STREAM_PF_INET : STREAM_PF_UNIX, 52 STREAM_SOCK_STREAM, 53 STREAM_IPPROTO_IP 54); 55 56// Set streams to non-blocking mode. 57stream_set_blocking($read, false); 58stream_set_blocking($write, false); 59 60$loop = new EventLoop; 61 62// Read data in a separate fiber after checking if the stream is readable. 63$fiber = new Fiber(function () use ($loop, $read): void { 64 echo "Waiting for data...\n"; 65 66 $fiber = Fiber::getCurrent(); 67 $loop->read($read, fn() => $fiber->resume()); 68 Fiber::suspend(); 69 70 $data = fread($read, 8192); 71 72 echo "Received data: ", $data, "\n"; 73}); 74 75// Start the fiber, which will suspend while waiting for a read event. 76$loop->defer(fn() => $fiber->start()); 77 78// Defer writing data to an event loop callback. 79$loop->defer(fn() => fwrite($write, "Hello, world!")); 80 81// Run the event loop. 82$loop->run();
