diff --git a/lockfile.php b/lockfile.php
new file mode 100644
index 0000000..91d1154
--- /dev/null
+++ b/lockfile.php
@@ -0,0 +1,111 @@
+<?php
+/** DomFramework
+    @package domframework
+    @author Dominique Fournier <dominique@fournier38.fr> */
+
+/** The lock management of files */
+class lockfile
+{
+  /** The Exclusive lock file */
+  public $storagelock = "./data/lockfile.lock";
+  /** The Read-Only lock file */
+  private $storagelockRO = FALSE;
+
+  /** This function lock the storage file until all is written.
+      If an other processus want to lock, it hang until the lock is released */
+  public function lockRW ()
+  {
+    if (!is_dir (dirname ($this->storagelock)))
+      @mkdir (dirname ($this->storagelock));
+    if (!is_dir (dirname ($this->storagelock)))
+      throw new Exception ("Can't create '".dirname ($this->storagelock)."'",
+                           500);
+    $lockid = uniqid() . '_' . md5 (mt_rand());
+    $startTime = microtime (TRUE);
+    // Stale lock : 60s old min
+    if (file_exists ($this->storagelock) &&
+        filemtime ($this->storagelock) < time() - 60)
+    {
+      // TODO : Log the Stale lock removing
+      unlink ($this->storagelock);
+    }
+
+    // Wait RW Lock
+    while (1)
+    {
+      while (file_exists ($this->storagelock))
+      {
+        usleep (100000);
+        clearstatcache (TRUE, $this->storagelock);
+        if (microtime (TRUE) > $startTime + 10)
+          throw new Exception ("Can't have the authorization lock RW in 10s",
+                               500);
+      }
+
+      file_put_contents ($this->storagelock, $lockid, FILE_APPEND);
+      clearstatcache (TRUE, $this->storagelock);
+      $cnt = file_get_contents ($this->storagelock);
+      if (substr ($cnt, 0, strlen ($lockid)) === $lockid)
+        break;
+    }
+
+    // Wait all the RO lock to go away
+    $startTime = microtime (TRUE);
+    while (count (glob ($this->storagelock."-*")) > 0)
+    {
+      usleep (100000);
+      if (microtime (TRUE) > $startTime + 10)
+        throw new Exception ("Can't have the authorization lock RO in 10s",
+                             500);
+    }
+
+    // I have the lock and no RO lock !
+    return TRUE;
+  }
+
+  /** This function lock the storage in share mode (to read the file without
+      modification at the same time) */
+  public function lockRO ()
+  {
+    if (!is_dir (dirname ($this->storagelock)))
+      @mkdir (dirname ($this->storagelock));
+    if (!is_dir (dirname ($this->storagelock)))
+      throw new Exception ("Can't create '".dirname ($this->storagelock)."'",
+                           500);
+    $lockid = uniqid() . '_' . md5 (mt_rand());
+    // Stale lock : 60s old min
+    if (file_exists ($this->storagelock) &&
+        filemtime ($this->storagelock) < time() - 60)
+    {
+      // TODO : Log the Stale lock removing
+      unlink ($this->storagelock);
+    }
+
+    // wait the removing of lockRW
+    $startTime = microtime (TRUE);
+    while (file_exists ($this->storagelock))
+    {
+      usleep (100000);
+      clearstatcache (TRUE, $this->storagelock);
+      if (microtime (TRUE) > $startTime + 10)
+        throw new Exception ("Can't have the authorization lock in 10s", 500);
+    }
+
+    touch ($this->storagelock."-".$lockid);
+    $this->storagelockRO = $this->storagelock."-".$lockid;
+  }
+
+  /** This function unlock RW the storage file */
+  public function unlockRW ()
+  {
+    if (file_exists ($this->storagelock))
+      unlink ($this->storagelock);
+  }
+
+  /** This function unlock RO the storage file */
+  public function unlockRO ()
+  {
+    if ($this->storagelockRO !== FALSE && file_exists ($this->storagelockRO))
+      unlink ($this->storagelockRO);
+  }
+}