mtWeb > Download > HTTP Keep-Alive Connections in PHP

<?php
    /* $Id: socket.php,v 1.3 2002/09/08 19:25:02 shaggy Exp $ */

/*
Copyright (c) 2001, 2002 by Martin Tsachev. All rights reserved.
mailto:martin@f2o.org
http://martin.f2o.org

Redistribution and use in source and binary forms,
with or without modification, are permitted provided
that the conditions available at
http://www.opensource.org/licenses/bsd-license.html
are met.
*/

Class Socket {
    var $fp = null;
    var $host;
    var $timeout = 30;
    var $maxlen = 4096;

    var $accept = 'text/html'; // MIME types to accept
    var $lang = 'en'; // Language to accept

    var $headers; // response headers
    var $body; // response body

    var $status; // HTTP status
    var $connection; // Connection type: close/keep-alive
    var $te; // Transfer encoding
    var $type; // returned MIME type


    function Socket($host) {
        $this->host = $host;
    }


    function setAccept($types) {
        $this->accept = $types;
    }


    function connect() {
        $this->fp = fsockopen($this->host, 80, $errno, $errstr, $this->timeout);

        if (!$this->fp) {
            return "Network error: $errstr ($errno)";
        }

        return 0;
    }


    function disconnect() {
        fclose($this->fp);
    }


    function get($uri) {
        $request =
            "GET $uri HTTP/1.1\r\n" .
            "Host: $this->host\r\n" .
            "Connection: Keep-Alive\r\n" .
            "Accept: $this->accept\r\n" .
            "Accept-Language: $this->lang\r\n" .
            "Accept-Encoding: chunked\r\n" .
            "User-Agent: PHP/4.2.1\r\n" .
            "\r\n";

        fputs($this->fp, $request);

        $this->headers = fgets($this->fp, $this->maxlen);
        if (!$this->headers) { // if disconnected meanwhile
            $this->connect();
            fputs($this->fp, $request);
            $this->headers = fgets($this->fp, $this->maxlen);
        }

        preg_match('|^HTTP.+ (.+) |', $this->headers, $matches);
        $this->status = $matches[1];

        $this->type = '';
        $this->connection = '';
        $this->te = '';
        
        while ($line = fgets($this->fp, $this->maxlen)) {
            if ($line == "\r\n") { break; }

            if (preg_match('/^Content-Length: (.+)/', $line, $matches)) {
                $length = (int) trim($matches[1]);
            }

            if (preg_match('/^Content-Type: (.+)/', $line, $matches)) {
                $this->type = strtolower(trim($matches[1]));
            }

            if (preg_match('/^Connection: (.+)/', $line, $matches)) {
                $this->connection = strtolower(trim($matches[1]));
            }

            if (preg_match('/^Transfer-Encoding: (.+)/', $line, $matches)) {
                $this->te = strtolower(trim($matches[1]));
            }

            $this->headers .= $line;
        }

        $this->body = '';

        if ($this->connection == 'close') {
            while (!feof($this->fp)) {
                $this->body .= fread($this->fp, $this->maxlen);
            }
            return ;
        }

        if (isset($length) and strpos($this->te, 'chunked') === false) {
            $this->body = fread($this->fp, $length);
            return ;
        }

        // chunked encoding
        $length = fgets($this->fp, $this->maxlen);
        $length = hexdec($length);

        while (true) {
            if ($length == 0) { break; }
            $this->body .= fread($this->fp, $length);

            fgets($this->fp, $this->maxlen);
            $length = fgets($this->fp, $this->maxlen);
            $length = hexdec($length);
        }

        fgets($this->fp, $this->maxlen);
    }

} // class Socket
?>