frontend: caching added

git-svn-id: file:///home/jan/tmp/wetterstation/trunk@247 dd492736-c11a-0410-ad51-8c26713eaf7f
2026-06-19 23:07:59 +00:00 · 2008-03-29 11:11:47 +00:00
parent 3534adf03a
commit 25960c71aa
10 changed files with 254 additions and 63 deletions
@@ -0,0 +1,109 @@
+<?
+
+  /* copyright: Jan Losinski, 2006
+     
+     at the Moment this is no free software, look at the
+     COPYING-File in the Main-Directory for License-Terms
+  */
+
+include_once($path."php_inc/config.inc.php");
+
+/* Connection-Klasse..ist fuer die Datenbankverbindung zustaendig */
+class Cacher{
+
+  function _cacheFileName($identifier){
+    $tmp_dir = Config::getCachePath();
+    if(!file_exists($tmp_dir)){
+      mkdir(dirname($tmp_dir), 0700);
+      mkdir($tmp_dir, 0700);
+    }
+    return $tmp_dir.md5($identifier);
+  }
+  function _lockFileName($identifier){
+    return Cacher::_cacheFileName($identifier).".lock";
+  }
+
+  function _checkCache($identifier, $expire){
+    $file = Cacher::_cacheFileName($identifier);
+    if (file_exists($file)){
+      if (filemtime($file) > (time() - ($expire *60))){
+	return true;
+      }
+    }
+    return false;
+  }
+
+  function _lockRead($identifier){
+    $handle = fopen(Cacher::_lockFileName($identifier), "w");
+    $i = 0;
+    while (flock($handle, LOCK_SH) != true){
+      usleep(10);
+      if ($i > 10){
+	fclose($handle);
+    echo "bla1";
+	return false;
+      }
+      $i ++;
+    }
+    return $handle;
+  }
+
+
+  function _unlockRead($handle){
+    flock($handle, LOCK_UN);
+    fclose($handle);
+  }
+
+
+  function _lockWrite($identifier){
+    $handle = fopen(Cacher::_lockFileName($identifier), "a+");
+    $i = 0;
+    while (flock($handle, LOCK_EX) != true){
+      usleep(10);
+      if ($i > 10){
+	fclose($handle);
+    echo "bla";
+	return false;
+      }
+      $i++;
+    }
+    return $handle;
+  }
+
+
+  function _unlockWrite($handle){
+    flock($handle, LOCK_UN);
+    fclose($handle);
+  }
+
+  function getCache($identifier, $expire){
+    if(!Config::performCaching()){
+      return false;
+    }
+    $lock = null;
+    if (Cacher::_checkCache($identifier, $expire) && (($lock = Cacher::_lockRead($identifier)) != false)){
+      $file = Cacher::_cacheFileName($identifier);
+      $handle = fopen($file, "r");
+      $serialized = fread ($handle, filesize ($file));
+      Cacher::_unlockRead($lock);
+      return unserialize($serialized);
+    } else {
+      return false;
+    }
+  }
+  function setCache($identifier, $var){
+    if(!Config::performCaching()){
+      return false;
+    }
+    $lock = null;
+    if (($lock =  Cacher::_lockWrite($identifier)) != false){
+      $file = Cacher::_cacheFileName($identifier);
+      $handle = fopen($file, "w");
+      fwrite($handle, serialize($var));
+      fclose($handle);
+      Cacher::_unlockWrite($lock);
+    }
+  }
+
+
+}