Using socket_connect with a reliable timeout in PHP

rich1.0phorkiehttps://p.cweiske.de/Using socket_connect with a reliable timeout in PHP · GitHubChristian Weiske86400900900 <link rel="stylesheet" href="https://p.cweiske.de/css/embed.css"/> <div class="phork" id="632"> <div class="phork-file"> <div class="phork-content"> <style type="text/css">/** * GeSHi (C) 2004 - 2007 Nigel McNie, 2007 - 2014 Benny Baumann * (http://qbnz.com/highlighter/ and http://geshi.org/) */ .php .de1, .php .de2 {font: normal normal 1em/1.2em monospace; margin:0; padding:0; background:none; vertical-align:top;} .php {font-family:monospace;} .php .imp {font-weight: bold; color: red;} .php li, .php .li1 {color: #DDD;} .php .ln {width:1px;text-align:right;margin:0;padding:0 2px;vertical-align:top;} .php .kw1 {color: #b1b100;} .php .kw2 {color: #000000; font-weight: bold;} .php .kw3 {color: #990000;} .php .kw4 {color: #009900; font-weight: bold;} .php .co1 {color: #666666; font-style: italic;} .php .co2 {color: #666666; font-style: italic;} .php .co3 {color: #0000cc; font-style: italic;} .php .co4 {color: #009933; font-style: italic;} .php .coMULTI {color: #666666; font-style: italic;} .php .es0 {color: #000099; font-weight: bold;} .php .es1 {color: #000099; font-weight: bold;} .php .es2 {color: #660099; font-weight: bold;} .php .es3 {color: #660099; font-weight: bold;} .php .es4 {color: #006699; font-weight: bold;} .php .es5 {color: #006699; font-weight: bold; font-style: italic;} .php .es6 {color: #009933; font-weight: bold;} .php .es_h {color: #000099; font-weight: bold;} .php .br0 {color: #009900;} .php .sy0 {color: #339933;} .php .sy1 {color: #000000; font-weight: bold;} .php .st0 {color: #0000ff;} .php .st_h {color: #0000ff;} .php .nu0 {color: #cc66cc;} .php .nu8 {color: #208080;} .php .nu12 {color: #208080;} .php .nu19 {color:#800080;} .php .me1 {color: #004000;} .php .me2 {color: #004000;} .php .re0 {color: #000088;} .php span.xtra { display:block; } </style><div class="code"><table class="php"><tbody><tr class="li1"><td class="ln"><pre class="de1">1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 </pre></td><td class="de1"><pre class="de1"><?php   /**  * I was having trouble with socket connections timing out reliably. Sometimes,  * my timeout would be reached. Other times, the connect would fail after three  * to six seconds. I finally figured out it had to do with trying to connect to  * a routable, non-localhost address. It seems the socket_connect call would  * not fail immediately for those connections. This function is what I finally  * ended up with that reliably connects to a working server, fails quickly for  * a server that has an address/port that is not reachable and will reach the  * timeout for routable addresses that are not up.  *  * Full Story: http://brian.moonspot.net/socket-connect-timeout  *  * Copyright (c) 2015, Brian Moon of DealNews.com, Inc.  * All rights reserved.  *  * Redistribution and use in source and binary forms, with or without  * modification, are permitted provided that the following conditions  * are met:  *  *  * Redistributions of source code must retain the above copyright  *    notice, this list of conditions and the following disclaimer.  *  * Redistributions in binary form must reproduce the above  *    copyright notice, this list of conditions and the following  *    disclaimer in the documentation and/or other materials provided  *    with the distribution.  *  * Neither the name of DealNews.com Inc. nor the names of its  *    contributors may be used to endorse or promote products derived  *    from this software without specific prior written permission.  *  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE  * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED  * OF THE POSSIBILITY OF SUCH DAMAGE.  *  */   /**  * Example:  *  * Assuming these hosts are valid for your setup, this example would produce  * something like this:  *  * Trying: Good host...  * resource(10) of type (Socket)  *  * Trying: Routable, but not up...  * Failed to connect to 10.1.2.30:4730. (timed out after 102.1051ms)  * NULL  *  * Trying: Up but not listening...  * Failed to connect to 127.0.0.1:7676. (111: Connection refused; after 0.051ms)  * NULL  *  * =====  *  * $timeout = 100;  *  * $hosts = array(  *     array(  *         "desc" => "Good host",  *         "host" => "127.0.0.1",  *         "port" => "4730"  *     ),  *     array(  *         "desc" => "Routable, but not up",  *         "host" => "10.1.2.30",  *         "port" => "4730"  *     ),  *     array(  *         "desc" => "Up but not listening",  *         "host" => "127.0.0.1",  *         "port" => "7676"  *     ),  * );  *  * foreach($hosts as $host){  *  *     echo "Trying: $host[desc]...\n";  *  *     try{  *         $socket = socket_connect_timeout($host["host"], $host["port"], $timeout);  *     } catch(Exception $e){  *         echo $e->getMessage()."\n";  *         $socket = null;  *     }  *  *     var_dump($socket);  *  *     echo "\n";  *  * }  *  */    function socket_connect_timeout($host, $port, $timeout=100){       $socket = <a href="http://www.php.net/socket_create">socket_create</a>(AF_INET, SOCK_STREAM, SOL_TCP);       /**      * Set the send and receive timeouts super low so that socket_connect      * will return to us quickly. We then loop and check the real timeout      * and check the socket error to decide if its conected yet or not.      */     $connect_timeval = <a href="http://www.php.net/array">array</a>(         "sec"=>0,         "usec" => 100     );     <a href="http://www.php.net/socket_set_option">socket_set_option</a>(         $socket,         SOL_SOCKET,         SO_SNDTIMEO,         $connect_timeval     );     <a href="http://www.php.net/socket_set_option">socket_set_option</a>(         $socket,         SOL_SOCKET,         SO_RCVTIMEO,         $connect_timeval     );       $now = <a href="http://www.php.net/microtime">microtime</a>(true);       /**      * Loop calling socket_connect. As long as the error is 115 (in progress)      * or 114 (already called) and our timeout has not been reached, keep      * trying.      */     $err = null;     $socket_connected = false;     do{         <a href="http://www.php.net/socket_clear_error">socket_clear_error</a>($socket);         $socket_connected = @<a href="http://www.php.net/socket_connect">socket_connect</a>($socket, $host, $port);         $err = <a href="http://www.php.net/socket_last_error">socket_last_error</a>($socket);         $elapsed = (<a href="http://www.php.net/microtime">microtime</a>(true) - $now) * 1000;     }     while (($err === 115 || $err === 114) && $elapsed < $timeout);       /**      * For some reason, socket_connect can return true even when it is      * not connected. Make sure it returned true the last error is zero      */     $socket_connected = $socket_connected && $err === 0;       if($socket_connected){           /**          * Set keep alive on so the other side does not drop us          */         <a href="http://www.php.net/socket_set_option">socket_set_option</a>($socket, SOL_SOCKET, SO_KEEPALIVE, 1);           /**          * set the real send/receive timeouts here now that we are connected          */         $timeval = <a href="http://www.php.net/array">array</a>(             "sec" => 0,             "usec" => 0         );         if($timeout >= 1000){             $ts_seconds = $timeout / 1000;             $timeval["sec"] = <a href="http://www.php.net/floor">floor</a>($ts_seconds);             $timeval["usec"] = ($ts_seconds - $timeval["sec"]) * 1000000;         } else {             $timeval["usec"] = $timeout * 1000;         }         <a href="http://www.php.net/socket_set_option">socket_set_option</a>(             $socket,             SOL_SOCKET,             SO_SNDTIMEO,             $timeval         );         <a href="http://www.php.net/socket_set_option">socket_set_option</a>(             $socket,             SOL_SOCKET,             SO_RCVTIMEO,             $timeval         );       } else {           $elapsed = <a href="http://www.php.net/round">round</a>($elapsed, 4);           if(!<a href="http://www.php.net/is_null">is_null</a>($err) && $err !== 0 && $err !== 114 && $err !== 115){             $message = "Failed to connect to $host:$port. ($err: ".<a href="http://www.php.net/socket_strerror">socket_strerror</a>($err)."; after {$elapsed}ms)";         } else {             $message = "Failed to connect to $host:$port. (timed out after {$elapsed}ms)";         }           throw new Exception($message);       }       return $socket;   }  </pre></td></tr></tbody></table></div> </div> <div class="phork-meta"> <a href="https://p.cweiske.de/632/rev-raw/b91da73dd7ccde3d7b93c1d698e94c66485567e9/socket_connect_timeout.php" style="float: right">view raw source</a> <a href="https://p.cweiske.de/632#socket_connect_timeout.php">socket_connect_timeout.php</a> </div> </div> </div>