gistfile1.php

<?php 

class Socket {
	private $_host = 'www.google.com.hk';
	private $_port = '80';
	private $_socket = null;
	private $_timeout = 30;
	private $_method = '';
	private $_protocol = 'tcp';
	
	public function __construct() {
	}

	public function connect() {
		//可以用stream_context_create的参数构造http请求
		$context = stream_context_create();
		
		$host = $this->_protocol.'://'.$this->_host;
		$this->_socket = stream_socket_client($host.':'.$this->_port, 
												$errno, 
												$errstr, 
												$this->_timeout, 
												STREAM_CLIENT_CONNECT || STREAM_CLIENT_PERSISTENT,
												$context
											);
		if (!$this->_socket) {
			echo 'connect '.$this->_socket.' error: '.$errno.' '.$errstr;
			return ;
		}

		if (!stream_set_timeout($this->_socket, (int)$this->_timeout)) {
			echo 'Unable to set the connection timeout';
			return ;
		}

	}

	public function write($method = 'GET', $headers = array(), $body = '') {
		$httpVersion = '1.1';
		
		//此处需要加上对url的处理	
		$path = '/';	
		$request = "{$method} {$path} HTTP/{$httpVersion}\r\n";
		
		foreach ($headers as $key => $value) {
			if (is_string($key)) {
				$header = ucfirst($key).": {$value}";
			} else {
				$header = $value;
			}
			
			$request .= "{$header}\r\n";
				
		}

		if (!empty($body)) {
			$request .= "\r\n{$body}";
		}
//var_dump($request);return ;
		if (!fwrite($this->_socket, $request)) {
			echo 'Error writing request to server';
			return ;
		}

		return $request;
	}
	

	public function read() {
		$response = '';
		while (($line = fgets($this->_socket)) !== false && !feof($this->_socket)) {
			if (strpos($line, 'HTTP') !== false) {
				$response .= $line;
				if (rtrim($line) === '') {
					break;
				}
			}
		}

		//首先处理http状态码
		$httpStatusCode = $this->_extractHttpStatusCode($response);
		
		//1**用于表示临时响应并需要请求者执行操作才能继续的状态码
		if ($httpStatusCode == 100 || $httpStatusCode == 101) {
			return $this->read();
		}
		
					

	}
	
	private function _extractHttpStatusCode($response) {
		$pattern = '/^HTTP\/[\d\.x]+ (\d+)/';
		preg_match($pattren, $response, $matches);

		if (isset($matches[1])) {
			return (int) $matches[1];
		} else {
			return null;
		}
	}
	
	private function _extractHttpResponseHeaders($response) {
		$headers = array();	
		$lastHeader = null;	

		$parts = preg_grep('/(?:\r?\n){2}/m', $response, 2);
		if ($parts[0]) {
			return $headers;
		}
		
		$lines = explode("\r\n", $parts[0]);
		
		foreach ($lines as $line) {
			$line = trim($line, "\r\n");
			if (empty($line)) {
				break;
			}

			if (preg_match("/^([\w-]+):\s+(.+)/", $line, $matches)) {
				$headerKey = strtolower($matcher[1]);
				$headerValue = $matcher[0];

				if (isset($headers[$headerKey])) {
					if (is_array($headers[$headerKey])) {
						$headers[$headerKey] = array($headerValue);
					}
				
					$headers[$headerKey][] = $headerValue;
				} else {
					$headers[$headerKey] = $headerValue;
				}

				$lastHeader = $headerKey;
			} elseif (preg_match('/^\s+(.+)$/', $line, $matches) && $lastHeader !== null) {
				if (is_array($headers[$lastHeader])) {
					end($headers[$lastHeader]);
					$lastHeaderKey = key($headers[$lastHeader]);
					$headers[$lastHeader][$lastHeaderKey] .= $matches[1];

				} else {
					$headers[$lastHeader] .= $matches[1];
				}
			}
		}
		
		return $headers;
	}

	public function close() {
		if (is_resource($this->_socket)) {
			fclose($this->_socket);
		}

		$this->_socket = null;
	}
}
?>