module.inc 13 KB
Newer Older
1
2
3
<?php
// $Id$

4
5
6
7
8
/**
 * @file
 * API for loading and interacting with Drupal modules.
 */

9
/**
10
 * Load all the modules that have been enabled in the system table.
11
 */
12
function module_load_all() {
13
14
15
  foreach (module_list(TRUE, FALSE) as $module) {
    drupal_load('module', $module);
  }
16
17
}

18
19
20
21
/**
 * Call a function repeatedly with each module in turn as an argument.
 */
function module_iterate($function, $argument = '') {
Kjartan's avatar
Kjartan committed
22
23
24
  foreach (module_list() as $name) {
    $function($name, $argument);
  }
25
26
}

27
/**
28
29
 * Collect a list of all loaded modules. During the bootstrap, return only
 * vital modules. See bootstrap.inc
30
31
32
33
34
 *
 * @param $refresh
 *   Whether to force the module list to be regenerated (such as after the
 *   administrator has changed the system settings).
 * @param $bootstrap
35
36
 *   Whether to return the reduced set of modules loaded in "bootstrap mode"
 *   for cached pages. See bootstrap.inc.
37
38
39
 * @param $sort
 *   By default, modules are ordered by weight and filename, settings this option
 *   to TRUE, module list will be ordered by module name.
40
41
42
 * @param $fixed_list
 *   (Optional) Override the module list with the given modules. Stays until the
 *   next call with $refresh = TRUE.
43
44
45
46
 * @return
 *   An associative array whose keys and values are the names of all loaded
 *   modules.
 */
47
function module_list($refresh = FALSE, $bootstrap = TRUE, $sort = FALSE, $fixed_list = NULL) {
48
  static $list, $sorted_list;
49

50
  if ($refresh || $fixed_list) {
51
    unset($sorted_list);
Dries's avatar
Dries committed
52
    $list = array();
53
54
55
56
57
    if ($fixed_list) {
      foreach ($fixed_list as $name => $module) {
        drupal_get_filename('module', $name, $module['filename']);
        $list[$name] = $name;
      }
58
59
    }
    else {
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
      if ($bootstrap) {
        $result = db_query("SELECT name, filename, throttle, bootstrap FROM {system} WHERE type = 'module' AND status = 1 AND bootstrap = 1 ORDER BY weight ASC, filename ASC");
      }
      else {
        $result = db_query("SELECT name, filename, throttle, bootstrap FROM {system} WHERE type = 'module' AND status = 1 ORDER BY weight ASC, filename ASC");
      }
      while ($module = db_fetch_object($result)) {
        if (file_exists($module->filename)) {
          // Determine the current throttle status and see if the module should be
          // loaded based on server load. We have to directly access the throttle
          // variables, since throttle.module may not be loaded yet.
          $throttle = ($module->throttle && variable_get('throttle_level', 0) > 0);
          if (!$throttle) {
            drupal_get_filename('module', $module->name, $module->filename);
            $list[$module->name] = $module->name;
          }
Dries's avatar
   
Dries committed
76
        }
77
      }
78
79
    }
  }
80
81
82
83
84
85
86
  if ($sort) {
    if (!isset($sorted_list)) {
      $sorted_list = $list;
      ksort($sorted_list);
    }
    return $sorted_list;
  }
87
88
89
  return $list;
}

Steven Wittens's avatar
Steven Wittens committed
90
91
/**
 * Rebuild the database cache of module files.
92
 *
Steven Wittens's avatar
Steven Wittens committed
93
94
95
96
97
 * @return
 *   The array of filesystem objects used to rebuild the cache.
 */
function module_rebuild_cache() {
  // Get current list of modules
98
  $files = drupal_system_listing('\.module$', 'modules', 'name', 0);
Steven Wittens's avatar
Steven Wittens committed
99
100
101
102
103
104
105

  // Extract current files from database.
  system_get_files_database($files, 'module');

  ksort($files);

  foreach ($files as $filename => $file) {
106
107
108
109
110
111
112
    $file->info = _module_parse_info_file(dirname($file->filename) .'/'. $file->name .'.info');
    // Skip modules that don't provide info.
    if (empty($file->info)) {
      unset($files[$filename]);
      continue;
    }
    $files[$filename]->info = $file->info;
Steven Wittens's avatar
Steven Wittens committed
113
114
115
116
117
118
119
120
121
122
123

    // log the critical hooks implemented by this module
    $bootstrap = 0;
    foreach (bootstrap_hooks() as $hook) {
      if (module_hook($file->name, $hook)) {
        $bootstrap = 1;
        break;
      }
    }

    // Update the contents of the system table:
124
    // TODO: We shouldn't actually need this description field anymore. Remove me next release.
Steven Wittens's avatar
Steven Wittens committed
125
    if (isset($file->status) || (isset($file->old_filename) && $file->old_filename != $file->filename)) {
126
      db_query("UPDATE {system} SET description = '%s', name = '%s', filename = '%s', bootstrap = %d WHERE filename = '%s'", $file->info['description'], $file->name, $file->filename, $bootstrap, $file->old_filename);
Steven Wittens's avatar
Steven Wittens committed
127
128
129
    }
    else {
      // This is a new module.
130
      db_query("INSERT INTO {system} (name, description, type, filename, status, throttle, bootstrap) VALUES ('%s', '%s', '%s', '%s', %d, %d, %d)", $file->name, $file->info['description'], 'module', $file->filename, $file->status, $file->throttle, $bootstrap);
Steven Wittens's avatar
Steven Wittens committed
131
132
    }
  }
133
134
135
  $files = _module_build_dependents($files);
  return $files;
}
Steven Wittens's avatar
Steven Wittens committed
136

137
138
139
140
141
142
143
144
145
/**
 * Find dependents; modules that are required by other modules.
 * Adds an array of dependents to the $file->info array.
 *
 * @return
 *   The list of files array with dependents added where applicable.
 */
function _module_build_dependents($files) {
  foreach ($files as $filename => $file) {
146
    if (isset($file->info['dependencies']) && is_array($file->info['dependencies'])) {
147
148
149
150
151
152
153
154
155
156
      foreach ($file->info['dependencies'] as $dependency) {
        if (!empty($files[$dependency]) && is_array($files[$dependency]->info)) {
          if (!isset($files[$dependency]->info['dependents'])) {
            $files[$dependency]->info['dependents'] = array();
          }
          $files[$dependency]->info['dependents'][] = $filename;
        }
      }
    }
  }
Steven Wittens's avatar
Steven Wittens committed
157
158
159
  return $files;
}

160
161
162
163
164
165
166
167
168
169
170
171
172
173
/**
 * Parse Drupal info file format.
 * Uses ini parser provided by php's parse_ini_file().
 *
 * Files should use the ini format to specify values.
 * e.g.
 * key = "value"
 * key2 = value2
 *
 * Some things to be aware of:
 * - This function is NOT for placing arbitrary module-specific settings. Use variable_get()
 *   and variable_set() for that.
 * - You may not use double-quotes in a value.
 *
174
175
176
177
 * Information stored in the module.info file:
 * name - The real name of the module for display purposes.
 * description - A brief description of the module.
 * dependencies - A space delimited list of the short names (shortname) of other modules this module depends on.
178
 * package - The name of the package of modules this module belongs to.
179
180
181
182
183
 *
 * Example of .info file:
 *   name = Forum
 *   description = Enables threaded discussions about general topics.
 *   dependencies = taxonomy comment
184
 *   package = Core - optional
185
 *
186
 * @param $filename
187
 *   The file we are parsing. Accepts file with relative or absolute path.
188
189
190
191
192
193
194
195
 * @return
 *   The info array.
 */
function _module_parse_info_file($filename) {
  $info = array();

  if (file_exists($filename)) {
    $info = parse_ini_file($filename);
196
197
198
199
200
201
202

    if (isset($info['dependencies'])) {
      $info['dependencies'] = explode(" ", $info['dependencies']);
    }
    else {
      $info['dependencies'] = NULL;
    }
203
  }
204
205
206
  return $info;
}

207
208
209
210
211
212
213
214
/**
 * Determine whether a given module exists.
 *
 * @param $module
 *   The name of the module (without the .module extension).
 * @return
 *   TRUE if the module is both installed and enabled.
 */
215
function module_exists($module) {
216
  $list = module_list();
217
  return array_key_exists($module, $list);
218
219
}

Steven Wittens's avatar
Steven Wittens committed
220
221
222
223
224
225
226
227
228
229
230
231
232
233
/**
 * Load a module's installation hooks.
 */
function module_load_install($module) {
  // Make sure the installation API is available
  include_once './includes/install.inc';

  $install_file = './'. drupal_get_path('module', $module) .'/'. $module .'.install';
  if (is_file($install_file)) {
    include_once $install_file;
  }
}

/**
234
 * Enable a given list of modules.
Steven Wittens's avatar
Steven Wittens committed
235
 *
236
237
 * @param $module_list
 *   An array of module names.
Steven Wittens's avatar
Steven Wittens committed
238
 */
239
240
241
242
243
244
245
246
247
248
function module_enable($module_list) {
  $invoke_modules = array();
  foreach ($module_list as $module) {
    $existing = db_fetch_object(db_query("SELECT name, status FROM {system} WHERE type = 'module' AND name = '%s'", $module));
    if ($existing->status === '0') {
      module_load_install($module);
      db_query("UPDATE {system} SET status = 1, throttle = 0 WHERE type = 'module' AND name = '%s'", $module);
      drupal_load('module', $module);
      $invoke_modules[] = $module;
    }
Steven Wittens's avatar
Steven Wittens committed
249
  }
250
251
252
253
254
255
256
257
258
259

  if (!empty($invoke_modules)) {
    // Refresh the module list to include the new enabled module.
    module_list(TRUE, FALSE);
    // Force to regenerate the stored list of hook implementations.
    module_implements('', FALSE, TRUE);
  }

  foreach ($invoke_modules as $module) {
    module_invoke($module, 'enable');
Steven Wittens's avatar
Steven Wittens committed
260
261
262
263
  }
}

/**
264
 * Disable a given set of modules.
Steven Wittens's avatar
Steven Wittens committed
265
 *
266
267
 * @param $module_list
 *   An array of module names.
Steven Wittens's avatar
Steven Wittens committed
268
 */
269
270
271
272
273
274
275
276
277
function module_disable($module_list) {
  $invoke_modules = array();
  foreach ($module_list as $module) {
    if (module_exists($module)) {
      module_load_install($module);
      module_invoke($module, 'disable');
      db_query("UPDATE {system} SET status = 0, throttle = 0 WHERE type = 'module' AND name = '%s'", $module);
      $invoke_modules[] = $module;
    }
Steven Wittens's avatar
Steven Wittens committed
278
  }
279
280
281
282
283
284

  if (!empty($invoke_modules)) {
    // Refresh the module list to exclude the disabled modules.
    module_list(TRUE, FALSE);
    // Force to regenerate the stored list of hook implementations.
    module_implements('', FALSE, TRUE);
Steven Wittens's avatar
Steven Wittens committed
285
286
287
  }
}

288
289
/**
 * @defgroup hooks Hooks
Dries's avatar
   
Dries committed
290
291
 * @{
 * Allow modules to interact with the Drupal core.
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
 *
 * Drupal's module system is based on the concept of "hooks". A hook is a PHP
 * function that is named foo_bar(), where "foo" is the name of the module (whose
 * filename is thus foo.module) and "bar" is the name of the hook. Each hook has
 * a defined set of parameters and a specified result type.
 *
 * To extend Drupal, a module need simply implement a hook. When Drupal wishes to
 * allow intervention from modules, it determines which modules implement a hook
 * and call that hook in all enabled modules that implement it.
 *
 * The available hooks to implement are explained here in the Hooks section of
 * the developer documentation. The string "hook" is used as a placeholder for
 * the module name is the hook definitions. For example, if the module file is
 * called example.module, then hook_help() as implemented by that module would be
 * defined as example_help().
 */

/**
 * Determine whether a module implements a hook.
 *
 * @param $module
 *   The name of the module (without the .module extension).
 * @param $hook
 *   The name of the hook (e.g. "help" or "menu").
 * @return
 *   TRUE if the module is both installed and enabled, and the hook is
 *   implemented in that module.
 */
function module_hook($module, $hook) {
  return function_exists($module .'_'. $hook);
322
323
}

Dries's avatar
   
Dries committed
324
325
326
327
328
/**
 * Determine which modules are implementing a hook.
 *
 * @param $hook
 *   The name of the hook (e.g. "help" or "menu").
329
330
331
 * @param $sort
 *   By default, modules are ordered by weight and filename, settings this option
 *   to TRUE, module list will be ordered by module name.
332
333
334
335
 * @param $refresh
 *   For internal use only: Whether to force the stored list of hook
 *   implementations to be regenerated (such as after enabling a new module,
 *   before processing hook_enable).
Dries's avatar
   
Dries committed
336
337
338
 * @return
 *   An array with the names of the modules which are implementing this hook.
 */
339
function module_implements($hook, $sort = FALSE, $refresh = FALSE) {
Dries's avatar
   
Dries committed
340
341
  static $implementations;

342
343
344
345
346
  if ($refresh) {
    unset($implementations);
    return;
  }

Dries's avatar
   
Dries committed
347
348
  if (!isset($implementations[$hook])) {
    $implementations[$hook] = array();
349
    $list = module_list(FALSE, TRUE, $sort);
Dries's avatar
   
Dries committed
350
351
352
353
354
355
356
    foreach ($list as $module) {
      if (module_hook($module, $hook)) {
        $implementations[$hook][] = $module;
      }
    }
  }

357
  // The explicit cast forces a copy to be made. This is needed because
358
359
360
361
362
363
  // $implementations[$hook] is only a reference to an element of
  // $implementations and if there are nested foreaches (due to nested node
  // API calls, for example), they would both manipulate the same array's
  // references, which causes some modules' hooks not to be called.
  // See also http://www.zend.com/zend/art/ref-count.php.
  return (array)$implementations[$hook];
Dries's avatar
   
Dries committed
364
365
}

366
367
368
369
370
371
372
373
374
375
376
377
/**
 * Invoke a hook in a particular module.
 *
 * @param $module
 *   The name of the module (without the .module extension).
 * @param $hook
 *   The name of the hook to invoke.
 * @param ...
 *   Arguments to pass to the hook implementation.
 * @return
 *   The return value of the hook implementation.
 */
378
379
380
381
function module_invoke() {
  $args = func_get_args();
  $module = array_shift($args);
  $hook = array_shift($args);
382
  $function = $module .'_'. $hook;
383
384
  if (module_hook($module, $hook)) {
    return call_user_func_array($function, $args);
385
386
387
388
389
390
391
392
393
394
395
396
397
  }
}
/**
 * Invoke a hook in all enabled modules that implement it.
 *
 * @param $hook
 *   The name of the hook to invoke.
 * @param ...
 *   Arguments to pass to the hook.
 * @return
 *   An array of return values of the hook implementations. If modules return
 *   arrays from their implementations, those are merged into one array.
 */
398
399
400
function module_invoke_all() {
  $args = func_get_args();
  $hook = array_shift($args);
401
  $return = array();
402
403
404
  foreach (module_implements($hook) as $module) {
    $function = $module .'_'. $hook;
    $result = call_user_func_array($function, $args);
405
    if (isset($result) && is_array($result)) {
406
407
      $return = array_merge($return, $result);
    }
408
409
410
    else if (isset($result)) {
      $return[] = $result;
    }
411
412
413
414
415
416
  }

  return $return;
}

/**
Dries's avatar
   
Dries committed
417
 * @} End of "defgroup hooks".
418
419
 */

420