web/lib/cachefuncs.inc.php

   1 <?php
   2
   3 if (!defined('CACHE_TYPE')) {
   4         define('CACHE_TYPE', 'NONE');
   5 }
   6
   7 # Check if APC extension is loaded, and set cache prefix if it is.
   8 if (CACHE_TYPE == 'APC' && !defined('EXTENSION_LOADED_APC')) {
   9         define('EXTENSION_LOADED_APC', extension_loaded('apc'));
  10         define('CACHE_PREFIX', 'aur:');
  11 }
  12
  13 # Check if memcache extension is loaded, and set cache prefix if it is.
  14 if (CACHE_TYPE == 'MEMCACHE' && !defined('EXTENSION_LOADED_MEMCACHE')) {
  15         define('EXTENSION_LOADED_MEMCACHE', extension_loaded('memcached'));
  16         define('CACHE_PREFIX', 'aur:');
  17         global $memcache;
  18         $memcache = new Memcached();
  19         $mcs = defined('MEMCACHE_SERVERS') ? MEMCACHE_SERVERS : '127.0.0.1:11211';
  20         foreach (explode(',', $mcs) as $elem) {
  21                 $telem = trim($elem);
  22                 $mcserver = explode(':', $telem);
  23                 $memcache->addServer($mcserver[0], intval($mcserver[1]));
  24         }
  25 }
  26
  27 # Set a value in the cache (currently APC) if cache is available for use. If
  28 # not available, this becomes effectively a no-op (return value is
  29 # false). Accepts an optional TTL (defaults to 600 seconds).
  30 function set_cache_value($key, $value, $ttl=600) {
  31         $status = false;
  32         if (defined('EXTENSION_LOADED_APC')) {
  33                 $status = apc_store(CACHE_PREFIX.$key, $value, $ttl);
  34         }
  35         if (defined('EXTENSION_LOADED_MEMCACHE')) {
  36                 global $memcache;
  37                 $status = $memcache->set(CACHE_PREFIX.$key, $value, $ttl);
  38         }
  39         return $status;
  40 }
  41
  42 # Get a value from the cache (currently APC) if cache is available for use. If
  43 # not available, this returns false (optionally sets passed in variable $status
  44 # to false, much like apc_fetch() behaves). This allows for testing the fetch
  45 # result appropriately even in the event that a 'false' value was the value in
  46 # the cache.
  47 function get_cache_value($key, &$status=false) {
  48         if(defined('EXTENSION_LOADED_APC')) {
  49                 $ret = apc_fetch(CACHE_PREFIX.$key, $status);
  50                 if ($status) {
  51                         return $ret;
  52                 }
  53         }
  54         if (defined('EXTENSION_LOADED_MEMCACHE')) {
  55                 global $memcache;
  56                 $ret = $memcache->get(CACHE_PREFIX.$key);
  57                 if (!$ret) {
  58                         $status = false;
  59                 }
  60                 else {
  61                         $status = true;
  62                 }
  63                 return $ret;
  64         }
  65         return $status;
  66 }
  67
  68 # Run a simple db query, retrieving and/or caching the value if APC is
  69 # available for use. Accepts an optional TTL value (defaults to 600 seconds).
  70 function db_cache_value($dbq, $key, $ttl=600) {
  71         $dbh = DB::connect();
  72         $status = false;
  73         $value = get_cache_value($key, $status);
  74         if (!$status) {
  75                 $result = $dbh->query($dbq);
  76                 $row = $result->fetch(PDO::FETCH_NUM);
  77                 $value = $row[0];
  78                 set_cache_value($key, $value, $ttl);
  79         }
  80         return $value;
  81 }
  82
  83 ?>