includes/memcached-client.php

   1 <?php
   2 //
   3 // +---------------------------------------------------------------------------+
   4 // | memcached client, PHP                                                     |
   5 // +---------------------------------------------------------------------------+
   6 // | Copyright (c) 2003 Ryan T. Dean <rtdean@cytherianage.net>                 |
   7 // | All rights reserved.                                                      |
   8 // |                                                                           |
   9 // | Redistribution and use in source and binary forms, with or without        |
  10 // | modification, are permitted provided that the following conditions        |
  11 // | are met:                                                                  |
  12 // |                                                                           |
  13 // | 1. Redistributions of source code must retain the above copyright         |
  14 // |    notice, this list of conditions and the following disclaimer.          |
  15 // | 2. Redistributions in binary form must reproduce the above copyright      |
  16 // |    notice, this list of conditions and the following disclaimer in the    |
  17 // |    documentation and/or other materials provided with the distribution.   |
  18 // |                                                                           |
  19 // | THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR      |
  20 // | IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
  21 // | OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.   |
  22 // | IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,          |
  23 // | INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT  |
  24 // | NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
  25 // | DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY     |
  26 // | THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT       |
  27 // | (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF  |
  28 // | THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.         |
  29 // +---------------------------------------------------------------------------+
  30 // | Author: Ryan T. Dean <rtdean@cytherianage.net>                            |
  31 // | Heavily influenced by the Perl memcached client by Brad Fitzpatrick.      |
  32 // |   Permission granted by Brad Fitzpatrick for relicense of ported Perl     |
  33 // |   client logic under 2-clause BSD license.                                |
  34 // +---------------------------------------------------------------------------+
  35 //
  36 // $TCAnet$
  37 //
  38
  39 /**
  40  * This is the PHP client for memcached - a distributed memory cache daemon.
  41  * More information is available at http://www.danga.com/memcached/
  42  *
  43  * Usage example:
  44  *
  45  * require_once 'memcached.php';
  46  *
  47  * $mc = new memcached(array(
  48  *              'servers' => array('127.0.0.1:10000',
  49  *                                 array('192.0.0.1:10010', 2),
  50  *                                 '127.0.0.1:10020'),
  51  *              'debug'   => false,
  52  *              'compress_threshold' => 10240,
  53  *              'persistant' => true));
  54  *
  55  * $mc->add('key', array('some', 'array'));
  56  * $mc->replace('key', 'some random string');
  57  * $val = $mc->get('key');
  58  *
  59  * @author  Ryan T. Dean <rtdean@cytherianage.net>
  60  * @package memcached-client
  61  * @version 0.1.2
  62  */
  63
  64 // {{{ requirements
  65 // }}}
  66
  67 // {{{ constants
  68 // {{{ flags
  69
  70 /**
  71  * Flag: indicates data is serialized
  72  */
  73 define("MEMCACHE_SERIALIZED", 1<<0);
  74
  75 /**
  76  * Flag: indicates data is compressed
  77  */
  78 define("MEMCACHE_COMPRESSED", 1<<1);
  79
  80 // }}}
  81
  82 /**
  83  * Minimum savings to store data compressed
  84  */
  85 define("COMPRESSION_SAVINGS", 0.20);
  86
  87 // }}}
  88
  89 // {{{ class memcached
  90 /**
  91  * memcached client class implemented using (p)fsockopen()
  92  *
  93  * @author  Ryan T. Dean <rtdean@cytherianage.net>
  94  * @package memcached-client
  95  */
  96 class memcached
  97 {
  98    // {{{ properties
  99    // {{{ public
 100
 101    /**
 102     * Command statistics
 103     *
 104     * @var     array
 105     * @access  public
 106     */
 107    var $stats;
 108
 109    // }}}
 110    // {{{ private
 111
 112    /**
 113     * Cached Sockets that are connected
 114     *
 115     * @var     array
 116     * @access  private
 117     */
 118    var $_cache_sock;
 119
 120    /**
 121     * Current debug status; 0 - none to 9 - profiling
 122     *
 123     * @var     boolean
 124     * @access  private
 125     */
 126    var $_debug;
 127
 128    /**
 129     * Dead hosts, assoc array, 'host'=>'unixtime when ok to check again'
 130     *
 131     * @var     array
 132     * @access  private
 133     */
 134    var $_host_dead;
 135
 136    /**
 137     * Is compression available?
 138     *
 139     * @var     boolean
 140     * @access  private
 141     */
 142    var $_have_zlib;
 143
 144    /**
 145     * Do we want to use compression?
 146     *
 147     * @var     boolean
 148     * @access  private
 149     */
 150    var $_compress_enable;
 151
 152    /**
 153     * At how many bytes should we compress?
 154     *
 155     * @var     interger
 156     * @access  private
 157     */
 158    var $_compress_threshold;
 159
 160    /**
 161     * Are we using persistant links?
 162     *
 163     * @var     boolean
 164     * @access  private
 165     */
 166    var $_persistant;
 167
 168    /**
 169     * If only using one server; contains ip:port to connect to
 170     *
 171     * @var     string
 172     * @access  private
 173     */
 174    var $_single_sock;
 175
 176    /**
 177     * Array containing ip:port or array(ip:port, weight)
 178     *
 179     * @var     array
 180     * @access  private
 181     */
 182    var $_servers;
 183
 184    /**
 185     * Our bit buckets
 186     *
 187     * @var     array
 188     * @access  private
 189     */
 190    var $_buckets;
 191
 192    /**
 193     * Total # of bit buckets we have
 194     *
 195     * @var     interger
 196     * @access  private
 197     */
 198    var $_bucketcount;
 199
 200    /**
 201     * # of total servers we have
 202     *
 203     * @var     interger
 204     * @access  private
 205     */
 206    var $_active;
 207
 208    /**
 209     * Stream timeout in seconds. Applies for example to fread()
 210     *
 211     * @var     integer
 212     * @access  private
 213     */
 214    var $_timeout_seconds;
 215
 216    /**
 217     * Stream timeout in microseconds
 218     *
 219     * @var     integer
 220     * @access  private
 221     */
 222    var $_timeout_microseconds;
 223
 224    // }}}
 225    // }}}
 226    // {{{ methods
 227    // {{{ public functions
 228    // {{{ memcached()
 229
 230    /**
 231     * Memcache initializer
 232     *
 233     * @param   array    $args    Associative array of settings
 234     *
 235     * @return  mixed
 236     * @access  public
 237     */
 238    function memcached ($args)
 239    {
 240       $this->set_servers(@$args['servers']);
 241       $this->_debug = @$args['debug'];
 242       $this->stats = array();
 243       $this->_compress_threshold = @$args['compress_threshold'];
 244       $this->_persistant = array_key_exists('persistant', $args) ? (@$args['persistant']) : false;
 245       $this->_compress_enable = true;
 246       $this->_have_zlib = function_exists("gzcompress");
 247
 248       $this->_cache_sock = array();
 249       $this->_host_dead = array();
 250
 251       $this->_timeout_seconds = 1;
 252       $this->_timeout_microseconds = 0;
 253    }
 254
 255    // }}}
 256    // {{{ add()
 257
 258    /**
 259     * Adds a key/value to the memcache server if one isn't already set with
 260     * that key
 261     *
 262     * @param   string   $key     Key to set with data
 263     * @param   mixed    $val     Value to store
 264     * @param   interger $exp     (optional) Time to expire data at
 265     *
 266     * @return  boolean
 267     * @access  public
 268     */
 269    function add ($key, $val, $exp = 0)
 270    {
 271       return $this->_set('add', $key, $val, $exp);
 272    }
 273
 274    // }}}
 275    // {{{ decr()
 276
 277    /**
 278     * Decriment a value stored on the memcache server
 279     *
 280     * @param   string   $key     Key to decriment
 281     * @param   interger $amt     (optional) Amount to decriment
 282     *
 283     * @return  mixed    FALSE on failure, value on success
 284     * @access  public
 285     */
 286    function decr ($key, $amt=1)
 287    {
 288       return $this->_incrdecr('decr', $key, $amt);
 289    }
 290
 291    // }}}
 292    // {{{ delete()
 293
 294    /**
 295     * Deletes a key from the server, optionally after $time
 296     *
 297     * @param   string   $key     Key to delete
 298     * @param   interger $time    (optional) How long to wait before deleting
 299     *
 300     * @return  boolean  TRUE on success, FALSE on failure
 301     * @access  public
 302     */
 303    function delete ($key, $time = 0)
 304    {
 305       if (!$this->_active)
 306          return false;
 307
 308       $sock = $this->get_sock($key);
 309       if (!is_resource($sock))
 310          return false;
 311
 312       $key = is_array($key) ? $key[1] : $key;
 313
 314       @$this->stats['delete']++;
 315       $cmd = "delete $key $time\r\n";
 316       if(!fwrite($sock, $cmd, strlen($cmd)))
 317       {
 318          $this->_dead_sock($sock);
 319          return false;
 320       }
 321       $res = trim(fgets($sock));
 322
 323       if ($this->_debug)
 324          $this->_debugprint(sprintf("MemCache: delete %s (%s)\n", $key, $res));
 325
 326       if ($res == "DELETED")
 327          return true;
 328       return false;
 329    }
 330
 331    // }}}
 332    // {{{ disconnect_all()
 333
 334    /**
 335     * Disconnects all connected sockets
 336     *
 337     * @access  public
 338     */
 339    function disconnect_all ()
 340    {
 341       foreach ($this->_cache_sock as $sock)
 342          fclose($sock);
 343
 344       $this->_cache_sock = array();
 345    }
 346
 347    // }}}
 348    // {{{ enable_compress()
 349
 350    /**
 351     * Enable / Disable compression
 352     *
 353     * @param   boolean  $enable  TRUE to enable, FALSE to disable
 354     *
 355     * @access  public
 356     */
 357    function enable_compress ($enable)
 358    {
 359       $this->_compress_enable = $enable;
 360    }
 361
 362    // }}}
 363    // {{{ forget_dead_hosts()
 364
 365    /**
 366     * Forget about all of the dead hosts
 367     *
 368     * @access  public
 369     */
 370    function forget_dead_hosts ()
 371    {
 372       $this->_host_dead = array();
 373    }
 374
 375    // }}}
 376    // {{{ get()
 377
 378    /**
 379     * Retrieves the value associated with the key from the memcache server
 380     *
 381     * @param  string   $key     Key to retrieve
 382     *
 383     * @return  mixed
 384     * @access  public
 385     */
 386    function get ($key)
 387    {
 388       if (!$this->_active)
 389          return false;
 390
 391       $sock = $this->get_sock($key);
 392
 393       if (!is_resource($sock))
 394          return false;
 395
 396       @$this->stats['get']++;
 397
 398       $cmd = "get $key\r\n";
 399       if (!fwrite($sock, $cmd, strlen($cmd)))
 400       {
 401          $this->_dead_sock($sock);
 402          return false;
 403       }
 404
 405       $val = array();
 406       $this->_load_items($sock, $val);
 407
 408       if ($this->_debug)
 409          foreach ($val as $k => $v)
 410             $this->_debugprint(@sprintf("MemCache: sock %s got %s => %s\r\n", serialize($sock), $k, $v));
 411
 412       return @$val[$key];
 413    }
 414
 415    // }}}
 416    // {{{ get_multi()
 417
 418    /**
 419     * Get multiple keys from the server(s)
 420     *
 421     * @param   array    $keys    Keys to retrieve
 422     *
 423     * @return  array
 424     * @access  public
 425     */
 426    function get_multi ($keys)
 427    {
 428       if (!$this->_active)
 429          return false;
 430
 431       $this->stats['get_multi']++;
 432
 433       foreach ($keys as $key)
 434       {
 435          $sock = $this->get_sock($key);
 436          if (!is_resource($sock)) continue;
 437          $key = is_array($key) ? $key[1] : $key;
 438          if (!isset($sock_keys[$sock]))
 439          {
 440             $sock_keys[$sock] = array();
 441             $socks[] = $sock;
 442          }
 443          $sock_keys[$sock][] = $key;
 444       }
 445
 446       // Send out the requests
 447       foreach ($socks as $sock)
 448       {
 449          $cmd = "get";
 450          foreach ($sock_keys[$sock] as $key)
 451          {
 452             $cmd .= " ". $key;
 453          }
 454          $cmd .= "\r\n";
 455
 456          if (fwrite($sock, $cmd, strlen($cmd)))
 457          {
 458             $gather[] = $sock;
 459          } else
 460          {
 461             $this->_dead_sock($sock);
 462          }
 463       }
 464
 465       // Parse responses
 466       $val = array();
 467       foreach ($gather as $sock)
 468       {
 469          $this->_load_items($sock, $val);
 470       }
 471
 472       if ($this->_debug)
 473          foreach ($val as $k => $v)
 474             $this->_debugprint(sprintf("MemCache: got %s => %s\r\n", $k, $v));
 475
 476       return $val;
 477    }
 478
 479    // }}}
 480    // {{{ incr()
 481
 482    /**
 483     * Increments $key (optionally) by $amt
 484     *
 485     * @param   string   $key     Key to increment
 486     * @param   interger $amt     (optional) amount to increment
 487     *
 488     * @return  interger New key value?
 489     * @access  public
 490     */
 491    function incr ($key, $amt=1)
 492    {
 493       return $this->_incrdecr('incr', $key, $amt);
 494    }
 495
 496    // }}}
 497    // {{{ replace()
 498
 499    /**
 500     * Overwrites an existing value for key; only works if key is already set
 501     *
 502     * @param   string   $key     Key to set value as
 503     * @param   mixed    $value   Value to store
 504     * @param   interger $exp     (optional) Experiation time
 505     *
 506     * @return  boolean
 507     * @access  public
 508     */
 509    function replace ($key, $value, $exp=0)
 510    {
 511       return $this->_set('replace', $key, $value, $exp);
 512    }
 513
 514    // }}}
 515    // {{{ run_command()
 516
 517    /**
 518     * Passes through $cmd to the memcache server connected by $sock; returns
 519     * output as an array (null array if no output)
 520     *
 521     * NOTE: due to a possible bug in how PHP reads while using fgets(), each
 522     *       line may not be terminated by a \r\n.  More specifically, my testing
 523     *       has shown that, on FreeBSD at least, each line is terminated only
 524     *       with a \n.  This is with the PHP flag auto_detect_line_endings set
 525     *       to falase (the default).
 526     *
 527     * @param   resource $sock    Socket to send command on
 528     * @param   string   $cmd     Command to run
 529     *
 530     * @return  array    Output array
 531     * @access  public
 532     */
 533    function run_command ($sock, $cmd)
 534    {
 535       if (!is_resource($sock))
 536          return array();
 537
 538       if (!fwrite($sock, $cmd, strlen($cmd)))
 539          return array();
 540
 541       while (true)
 542       {
 543          $res = fgets($sock);
 544          $ret[] = $res;
 545          if (preg_match('/^END/', $res))
 546             break;
 547          if (strlen($res) == 0)
 548             break;
 549       }
 550       return $ret;
 551    }
 552
 553    // }}}
 554    // {{{ set()
 555
 556    /**
 557     * Unconditionally sets a key to a given value in the memcache.  Returns true
 558     * if set successfully.
 559     *
 560     * @param   string   $key     Key to set value as
 561     * @param   mixed    $value   Value to set
 562     * @param   interger $exp     (optional) Experiation time
 563     *
 564     * @return  boolean  TRUE on success
 565     * @access  public
 566     */
 567    function set ($key, $value, $exp=0)
 568    {
 569       return $this->_set('set', $key, $value, $exp);
 570    }
 571
 572    // }}}
 573    // {{{ set_compress_threshold()
 574
 575    /**
 576     * Sets the compression threshold
 577     *
 578     * @param   interger $thresh  Threshold to compress if larger than
 579     *
 580     * @access  public
 581     */
 582    function set_compress_threshold ($thresh)
 583    {
 584       $this->_compress_threshold = $thresh;
 585    }
 586
 587    // }}}
 588    // {{{ set_debug()
 589
 590    /**
 591     * Sets the debug flag
 592     *
 593     * @param   boolean  $dbg     TRUE for debugging, FALSE otherwise
 594     *
 595     * @access  public
 596     *
 597     * @see     memcahced::memcached
 598     */
 599    function set_debug ($dbg)
 600    {
 601       $this->_debug = $dbg;
 602    }
 603
 604    // }}}
 605    // {{{ set_servers()
 606
 607    /**
 608     * Sets the server list to distribute key gets and puts between
 609     *
 610     * @param   array    $list    Array of servers to connect to
 611     *
 612     * @access  public
 613     *
 614     * @see     memcached::memcached()
 615     */
 616    function set_servers ($list)
 617    {
 618       $this->_servers = $list;
 619       $this->_active = count($list);
 620       $this->_buckets = null;
 621       $this->_bucketcount = 0;
 622
 623       $this->_single_sock = null;
 624       if ($this->_active == 1)
 625          $this->_single_sock = $this->_servers[0];
 626    }
 627
 628    /**
 629     * Sets the timeout for new connections
 630     *
 631     * @param   integer  $seconds Number of seconds
 632     * @param   integer  $microseconds  Number of microseconds
 633     *
 634     * @access  public
 635     */
 636    function set_timeout ($seconds, $microseconds)
 637    {
 638       $this->_timeout_seconds = $seconds;
 639       $this->_timeout_microseconds = $microseconds;
 640    }
 641
 642    // }}}
 643    // }}}
 644    // {{{ private methods
 645    // {{{ _close_sock()
 646
 647    /**
 648     * Close the specified socket
 649     *
 650     * @param   string   $sock    Socket to close
 651     *
 652     * @access  private
 653     */
 654    function _close_sock ($sock)
 655    {
 656       $host = array_search($sock, $this->_cache_sock);
 657       fclose($this->_cache_sock[$host]);
 658       unset($this->_cache_sock[$host]);
 659    }
 660
 661    // }}}
 662    // {{{ _connect_sock()
 663
 664    /**
 665     * Connects $sock to $host, timing out after $timeout
 666     *
 667     * @param   interger $sock    Socket to connect
 668     * @param   string   $host    Host:IP to connect to
 669     * @param   float    $timeout (optional) Timeout value, defaults to 0.25s
 670     *
 671     * @return  boolean
 672     * @access  private
 673     */
 674    function _connect_sock (&$sock, $host, $timeout = 0.25)
 675    {
 676       list ($ip, $port) = explode(":", $host);
 677       if ($this->_persistant == 1)
 678       {
 679          $sock = @pfsockopen($ip, $port, $errno, $errstr, $timeout);
 680       } else
 681       {
 682          $sock = @fsockopen($ip, $port, $errno, $errstr, $timeout);
 683       }
 684
 685       if (!$sock) {
 686          if ($this->_debug)
 687             $this->_debugprint( "Error connecting to $host: $errstr\n" );
 688          return false;
 689       }
 690
 691       // Initialise timeout
 692       stream_set_timeout($sock, $this->_timeout_seconds, $this->_timeout_microseconds);
 693
 694       return true;
 695    }
 696
 697    // }}}
 698    // {{{ _dead_sock()
 699
 700    /**
 701     * Marks a host as dead until 30-40 seconds in the future
 702     *
 703     * @param   string   $sock    Socket to mark as dead
 704     *
 705     * @access  private
 706     */
 707    function _dead_sock ($sock)
 708    {
 709       $host = array_search($sock, $this->_cache_sock);
 710       @list ($ip, $port) = explode(":", $host);
 711       $this->_host_dead[$ip] = time() + 30 + intval(rand(0, 10));
 712       $this->_host_dead[$host] = $this->_host_dead[$ip];
 713       unset($this->_cache_sock[$host]);
 714    }
 715
 716    // }}}
 717    // {{{ get_sock()
 718
 719    /**
 720     * get_sock
 721     *
 722     * @param   string   $key     Key to retrieve value for;
 723     *
 724     * @return  mixed    resource on success, false on failure
 725     * @access  private
 726     */
 727    function get_sock ($key)
 728    {
 729       if (!$this->_active)
 730          return false;
 731
 732       if ($this->_single_sock !== null)
 733          return $this->sock_to_host($this->_single_sock);
 734
 735       $hv = is_array($key) ? intval($key[0]) : $this->_hashfunc($key);
 736
 737       if ($this->_buckets === null)
 738       {
 739          foreach ($this->_servers as $v)
 740          {
 741             if (is_array($v))
 742             {
 743                for ($i=0; $i<$v[1]; $i++)
 744                   $bu[] = $v[0];
 745             } else
 746             {
 747                $bu[] = $v;
 748             }
 749          }
 750          $this->_buckets = $bu;
 751          $this->_bucketcount = count($bu);
 752       }
 753
 754       $realkey = is_array($key) ? $key[1] : $key;
 755       for ($tries = 0; $tries<20; $tries++)
 756       {
 757          $host = $this->_buckets[$hv % $this->_bucketcount];
 758          $sock = $this->sock_to_host($host);
 759          if (is_resource($sock))
 760             return $sock;
 761          $hv += $this->_hashfunc($tries . $realkey);
 762       }
 763
 764       return false;
 765    }
 766
 767    // }}}
 768    // {{{ _hashfunc()
 769
 770    /**
 771     * Creates a hash interger based on the $key
 772     *
 773     * @param   string   $key     Key to hash
 774     *
 775     * @return  interger Hash value
 776     * @access  private
 777     */
 778    function _hashfunc ($key)
 779    {
 780       # Hash function must on [0,0x7ffffff]
 781       # We take the first 31 bits of the MD5 hash, which unlike the hash
 782       # function used in a previous version of this client, works
 783       return hexdec(substr(md5($key),0,8)) & 0x7fffffff;
 784    }
 785
 786    // }}}
 787    // {{{ _incrdecr()
 788
 789    /**
 790     * Perform increment/decriment on $key
 791     *
 792     * @param   string   $cmd     Command to perform
 793     * @param   string   $key     Key to perform it on
 794     * @param   interger $amt     Amount to adjust
 795     *
 796     * @return  interger    New value of $key
 797     * @access  private
 798     */
 799    function _incrdecr ($cmd, $key, $amt=1)
 800    {
 801       if (!$this->_active)
 802          return null;
 803
 804       $sock = $this->get_sock($key);
 805       if (!is_resource($sock))
 806          return null;
 807
 808       $key = is_array($key) ? $key[1] : $key;
 809       @$this->stats[$cmd]++;
 810       if (!fwrite($sock, "$cmd $key $amt\r\n"))
 811          return $this->_dead_sock($sock);
 812
 813       stream_set_timeout($sock, 1, 0);
 814       $line = fgets($sock);
 815       if (!preg_match('/^(\d+)/', $line, $match))
 816          return null;
 817       return $match[1];
 818    }
 819
 820    // }}}
 821    // {{{ _load_items()
 822
 823    /**
 824     * Load items into $ret from $sock
 825     *
 826     * @param   resource $sock    Socket to read from
 827     * @param   array    $ret     Returned values
 828     *
 829     * @access  private
 830     */
 831    function _load_items ($sock, &$ret)
 832    {
 833       while (1)
 834       {
 835          $decl = fgets($sock);
 836          if ($decl == "END\r\n")
 837          {
 838             return true;
 839          } elseif (preg_match('/^VALUE (\S+) (\d+) (\d+)\r\n$/', $decl, $match))
 840          {
 841             list($rkey, $flags, $len) = array($match[1], $match[2], $match[3]);
 842             $bneed = $len+2;
 843             $offset = 0;
 844
 845             while ($bneed > 0)
 846             {
 847                $data = fread($sock, $bneed);
 848                $n = strlen($data);
 849                if ($n == 0)
 850                   break;
 851                $offset += $n;
 852                $bneed -= $n;
 853                @$ret[$rkey] .= $data;
 854             }
 855
 856             if ($offset != $len+2)
 857             {
 858                // Something is borked!
 859                if ($this->_debug)
 860                   $this->_debugprint(sprintf("Something is borked!  key %s expecting %d got %d length\n", $rkey, $len+2, $offset));
 861
 862                unset($ret[$rkey]);
 863                $this->_close_sock($sock);
 864                return false;
 865             }
 866
 867             if ($this->_have_zlib && $flags & MEMCACHE_COMPRESSED)
 868                $ret[$rkey] = gzuncompress($ret[$rkey]);
 869
 870             $ret[$rkey] = rtrim($ret[$rkey]);
 871
 872             if ($flags & MEMCACHE_SERIALIZED)
 873                $ret[$rkey] = unserialize($ret[$rkey]);
 874
 875          } else
 876          {
 877             $this->_debugprint("Error parsing memcached response\n");
 878             return 0;
 879          }
 880       }
 881    }
 882
 883    // }}}
 884    // {{{ _set()
 885
 886    /**
 887     * Performs the requested storage operation to the memcache server
 888     *
 889     * @param   string   $cmd     Command to perform
 890     * @param   string   $key     Key to act on
 891     * @param   mixed    $val     What we need to store
 892     * @param   interger $exp     When it should expire
 893     *
 894     * @return  boolean
 895     * @access  private
 896     */
 897    function _set ($cmd, $key, $val, $exp)
 898    {
 899       if (!$this->_active)
 900          return false;
 901
 902       $sock = $this->get_sock($key);
 903       if (!is_resource($sock))
 904          return false;
 905
 906       @$this->stats[$cmd]++;
 907
 908       $flags = 0;
 909
 910       if (!is_scalar($val))
 911       {
 912          $val = serialize($val);
 913          $flags |= MEMCACHE_SERIALIZED;
 914          if ($this->_debug)
 915             $this->_debugprint(sprintf("client: serializing data as it is not scalar\n"));
 916       }
 917
 918       $len = strlen($val);
 919
 920       if ($this->_have_zlib && $this->_compress_enable &&
 921           $this->_compress_threshold && $len >= $this->_compress_threshold)
 922       {
 923          $c_val = gzcompress($val, 9);
 924          $c_len = strlen($c_val);
 925
 926          if ($c_len < $len*(1 - COMPRESSION_SAVINGS))
 927          {
 928             if ($this->_debug)
 929                $this->_debugprint(sprintf("client: compressing data; was %d bytes is now %d bytes\n", $len, $c_len));
 930             $val = $c_val;
 931             $len = $c_len;
 932             $flags |= MEMCACHE_COMPRESSED;
 933          }
 934       }
 935       if (!fwrite($sock, "$cmd $key $flags $exp $len\r\n$val\r\n"))
 936          return $this->_dead_sock($sock);
 937
 938       $line = trim(fgets($sock));
 939
 940       if ($this->_debug)
 941       {
 942          if ($flags & MEMCACHE_COMPRESSED)
 943             $val = 'compressed data';
 944          $this->_debugprint(sprintf("MemCache: %s %s => %s (%s)\n", $cmd, $key, $val, $line));
 945       }
 946       if ($line == "STORED")
 947          return true;
 948       return false;
 949    }
 950
 951    // }}}
 952    // {{{ sock_to_host()
 953
 954    /**
 955     * Returns the socket for the host
 956     *
 957     * @param   string   $host    Host:IP to get socket for
 958     *
 959     * @return  mixed    IO Stream or false
 960     * @access  private
 961     */
 962    function sock_to_host ($host)
 963    {
 964       if (isset($this->_cache_sock[$host]))
 965          return $this->_cache_sock[$host];
 966
 967       $now = time();
 968       list ($ip, $port) = explode (":", $host);
 969       if (isset($this->_host_dead[$host]) && $this->_host_dead[$host] > $now ||
 970           isset($this->_host_dead[$ip]) && $this->_host_dead[$ip] > $now)
 971          return null;
 972
 973       if (!$this->_connect_sock($sock, $host))
 974          return $this->_dead_sock($host);
 975
 976       // Do not buffer writes
 977       stream_set_write_buffer($sock, 0);
 978
 979       $this->_cache_sock[$host] = $sock;
 980
 981       return $this->_cache_sock[$host];
 982    }
 983
 984    function _debugprint($str){
 985       print($str);
 986    }
 987
 988    // }}}
 989    // }}}
 990    // }}}
 991 }
 992
 993 // }}}
 994 ?>