functions/plugin.php

   1 <?php
   2
   3 /**
   4  ** plugin.php
   5  **
   6  ** This file provides the framework for a plugin architecture.
   7  **
   8  ** Plugins will eventually be a way to provide added functionality
   9  ** without having to patch the SquirrelMail source code. Have some
  10  ** patience, though, as the these funtions might change in the near
  11  ** future.
  12  **
  13  ** Documentation on how to write plugins might show up some time.
  14  **
  15  ** $Id$
  16  **/
  17
  18
  19    $plugin_php = true;
  20    $plugin_general_debug = false;
  21
  22    // This function adds a plugin
  23    function use_plugin ($name) {
  24       global $plugin_general_debug;
  25
  26       if (file_exists('../plugins/'.$name.'/setup.php')) {
  27          if ($plugin_general_debug)
  28             echo "plugin:  --  Loading $name/setup.php<br>\n";
  29          include ('../plugins/'.$name.'/setup.php');
  30          $function = 'squirrelmail_plugin_init_'.$name;
  31          if (function_exists($function))
  32          {
  33             if ($plugin_general_debug)
  34                echo "plugin:  ---- Executing $function to init plugin<br>\n";
  35             $function();
  36          }
  37          elseif ($plugin_general_debug)
  38             echo "plugin:  -- Init function $function doesn't exist.<br>\n";
  39       }
  40       elseif ($plugin_general_debug)
  41          echo "plugin:  Couldn't find $name/setup.php<br>\n";
  42    }
  43
  44    // This function executes a hook
  45    function do_hook ($name) {
  46       global $squirrelmail_plugin_hooks;
  47       $Data = func_get_args();
  48       if (isset($squirrelmail_plugin_hooks[$name]) &&
  49           is_array($squirrelmail_plugin_hooks[$name])) {
  50          foreach ($squirrelmail_plugin_hooks[$name] as $id => $function) {
  51             // Add something to set correct gettext domain for plugin
  52             if (function_exists($function)) {
  53                 $function($Data);
  54             }
  55          }
  56       }
  57
  58       // Variable-length argument lists have a slight problem when
  59       // passing values by reference.  Pity.  This is a workaround.
  60       return $Data;
  61   }
  62
  63    // On startup, register all plugins configured for use
  64    if (isset($plugins) && is_array($plugins))
  65       foreach ($plugins as $id => $name)
  66       {
  67          if ($plugin_general_debug)
  68             echo "plugin:  Attempting load of plugin $name<br>\n";
  69          use_plugin($name);
  70       }
  71
  72 ?>