module.inc 16.1 KB
Newer Older
1
2
3
<?php
// $Id$

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

9
10
11
12
13
14
15
16
17
18
19
/**
 * Pass this to module_implements when its cache needs to be written.
 */
define('MODULE_IMPLEMENTS_WRITE_CACHE', -1);

/**
 * Pass this to module_implements when its cache needs to be cleared.
 */
define('MODULE_IMPLEMENTS_CLEAR_CACHE', -2);


20
/**
21
 * Load all the modules that have been enabled in the system table.
22
 */
23
function module_load_all() {
24
  foreach (module_list(TRUE) as $module) {
25
26
    drupal_load('module', $module);
  }
27
28
}

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

49
  if (empty($list) || $refresh || $fixed_list) {
Dries's avatar
Dries committed
50
    $list = array();
51
    $sorted_list = NULL;
52
53
54
55
56
    if ($fixed_list) {
      foreach ($fixed_list as $name => $module) {
        drupal_get_filename('module', $name, $module['filename']);
        $list[$name] = $name;
      }
57
58
    }
    else {
59
60
61
62
63
64
      // The module name (rather than the filename) is used as the fallback
      // weighting in order to guarantee consistent behavior across different
      // Drupal installations, which might have modules installed in different
      // locations in the file system. The ordering here must also be
      // consistent with the one used in module_implements().
      $result = db_query("SELECT name, filename FROM {system} WHERE type = 'module' AND status = 1 ORDER BY weight ASC, name ASC");
65
      foreach ($result as $module) {
66
        if (file_exists($module->filename)) {
67
68
          drupal_get_filename('module', $module->name, $module->filename);
          $list[$module->name] = $module->name;
Dries's avatar
   
Dries committed
69
        }
70
      }
71
72
    }
  }
73
74
75
76
77
78
79
  if ($sort) {
    if (!isset($sorted_list)) {
      $sorted_list = $list;
      ksort($sorted_list);
    }
    return $sorted_list;
  }
80
81
82
  return $list;
}

83
/**
84
 * Find dependencies any level deep and fill in required by information too.
85
86
87
 *
 * @param $files
 *   The array of filesystem objects used to rebuild the cache.
88
 * @return
89
90
91
92
93
 *   The same array with the new keys for each module:
 *   - requires: An array with the keys being the modules that this module
 *     requires.
 *   - required_by: An array with the keys being the modules that will not work
 *     without this module.
94
 */
95
function _module_build_dependencies($files) {
96
  require_once DRUPAL_ROOT . '/includes/graph.inc';
97
98
99
100
101
102
103
  $roots = $files;
  foreach ($files as $filename => $file) {
    $graph[$file->name]['edges'] = array();
    if (isset($file->info['dependencies']) && is_array($file->info['dependencies'])) {
      foreach ($file->info['dependencies'] as $dependency_name) {
        $graph[$file->name]['edges'][$dependency_name] = 1;
        unset($roots[$dependency_name]);
104
105
      }
    }
106
107
108
  }
  drupal_depth_first_search($graph, array_keys($roots));
  foreach ($graph as $module => $data) {
109
    $files[$module]->required_by = isset($data['reverse_paths']) ? $data['reverse_paths'] : array();
110
111
112
    $files[$module]->requires = isset($data['paths']) ? $data['paths'] : array();
    $files[$module]->sort = $data['weight'];
  }
Steven Wittens's avatar
Steven Wittens committed
113
114
115
  return $files;
}

116
117
118
119
120
121
122
123
/**
 * Determine whether a given module exists.
 *
 * @param $module
 *   The name of the module (without the .module extension).
 * @return
 *   TRUE if the module is both installed and enabled.
 */
124
function module_exists($module) {
125
  $list = module_list();
126
  return isset($list[$module]);
127
128
}

Steven Wittens's avatar
Steven Wittens committed
129
130
131
132
133
/**
 * Load a module's installation hooks.
 */
function module_load_install($module) {
  // Make sure the installation API is available
134
  include_once DRUPAL_ROOT . '/includes/install.inc';
Steven Wittens's avatar
Steven Wittens committed
135

136
  module_load_include('install', $module);
137
138
139
140
}

/**
 * Load a module include file.
141
142
143
144
145
146
147
148
 * 
 * Examples:
 * @code
 *   // Load node.admin.inc from the node module
 *   module_load_include('inc', 'node', 'node.admin');
 *   // Load node.install from the node module
 *   module_load_include('install', 'node'); 
 * @endcode
149
150
151
152
153
154
 *
 * @param $type
 *   The include file's type (file extension).
 * @param $module
 *   The module to which the include file belongs.
 * @param $name
155
156
 *   Optionally, specify the base file name (without the $type extension). 
 *   If not set, $module is used.
157
158
159
160
161
162
 */
function module_load_include($type, $module, $name = NULL) {
  if (empty($name)) {
    $name = $module;
  }

163
  if (drupal_function_exists('drupal_get_path')) {
164
165
166
167
168
    $file = DRUPAL_ROOT . '/' . drupal_get_path('module', $module) . "/$name.$type";
    if (is_file($file)) {
      require_once $file;
      return $file;
    }
169
  }
170
  return FALSE;
171
172
173
174
175
176
177
178
179
180
}

/**
 * Load an include file for each of the modules that have been enabled in
 * the system table.
 */
function module_load_all_includes($type, $name = NULL) {
  $modules = module_list();
  foreach ($modules as $module) {
    module_load_include($type, $module, $name);
Steven Wittens's avatar
Steven Wittens committed
181
182
183
184
  }
}

/**
185
 * Enable a given list of modules.
Steven Wittens's avatar
Steven Wittens committed
186
 *
187
188
 * @param $module_list
 *   An array of module names.
189
190
 * @param $disable_modules_installed_hook
 *   Normally just testing wants to set this to TRUE.
Steven Wittens's avatar
Steven Wittens committed
191
 */
192
function module_enable($module_list, $disable_modules_installed_hook = FALSE) {
193
  $invoke_modules = array();
194
195
196
197
  
  // Try to install the enabled modules and collect which were installed.
  // $module_list is not changed and already installed modules are ignored.
  $modules_installed = array_filter($module_list, '_drupal_install_module');
198
  foreach ($module_list as $module) {
199
200
201
202
    $existing = db_query("SELECT status FROM {system} WHERE type = :type AND name = :name", array(
      ':type' => 'module',
      ':name' => $module))
      ->fetchObject();
203
    if ($existing->status == 0) {
204
      module_load_install($module);
205
206
207
208
209
      db_update('system')
        ->fields(array('status' => 1))
        ->condition('type', 'module')
        ->condition('name', $module)
        ->execute();
210
211
      drupal_load('module', $module);
      $invoke_modules[] = $module;
212
      watchdog('system', '%module module enabled.', array('%module' => $module), WATCHDOG_INFO);
213
    }
Steven Wittens's avatar
Steven Wittens committed
214
  }
215
216
217

  if (!empty($invoke_modules)) {
    // Refresh the module list to include the new enabled module.
218
    module_list(TRUE);
219
    // Force to regenerate the stored list of hook implementations.
220
    registry_rebuild();
221
222
223
224
225

    // If any modules were newly installed, execute the hook for them.
    if (!$disable_modules_installed_hook && !empty($modules_installed)) {
      module_invoke_all('modules_installed', $modules_installed);
    }
226
227
228
229
  }

  foreach ($invoke_modules as $module) {
    module_invoke($module, 'enable');
230
    // Check if node_access table needs rebuilding.
231
232
233
    // We check for the existence of node_access_needs_rebuild() since
    // at install time, module_enable() could be called while node.module
    // is not enabled yet.
234
    if (drupal_function_exists('node_access_needs_rebuild') && !node_access_needs_rebuild() && module_hook($module, 'node_grants')) {
235
236
      node_access_needs_rebuild(TRUE);
    }
Steven Wittens's avatar
Steven Wittens committed
237
  }
238
239
240
241
242
243

  if (!empty($invoke_modules)) {
    // Invoke the hook_module_enable after all the modules have been
    // enabled.
    module_invoke_all('modules_enabled', $invoke_modules);
  }
Steven Wittens's avatar
Steven Wittens committed
244
245
246
}

/**
247
 * Disable a given set of modules.
Steven Wittens's avatar
Steven Wittens committed
248
 *
249
250
 * @param $module_list
 *   An array of module names.
Steven Wittens's avatar
Steven Wittens committed
251
 */
252
253
254
255
function module_disable($module_list) {
  $invoke_modules = array();
  foreach ($module_list as $module) {
    if (module_exists($module)) {
256
257
258
259
260
      // Check if node_access table needs rebuilding.
      if (!node_access_needs_rebuild() && module_hook($module, 'node_grants')) {
        node_access_needs_rebuild(TRUE);
      }

261
262
      module_load_install($module);
      module_invoke($module, 'disable');
263
264
265
266
267
      db_update('system')
        ->fields(array('status' => 0))
        ->condition('type', 'module')
        ->condition('name', $module)
        ->execute();
268
      $invoke_modules[] = $module;
269
      watchdog('system', '%module module disabled.', array('%module' => $module), WATCHDOG_INFO);
270
    }
Steven Wittens's avatar
Steven Wittens committed
271
  }
272
273

  if (!empty($invoke_modules)) {
274
275
276
    // Invoke hook_module_disable before disabling modules,
    // so we can still call module hooks to get information.
    module_invoke_all('modules_disabled', $invoke_modules);
277
    // Refresh the module list to exclude the disabled modules.
278
    module_list(TRUE);
279
    // Force to regenerate the stored list of hook implementations.
280
    registry_rebuild();
Steven Wittens's avatar
Steven Wittens committed
281
  }
282

283
  // If there remains no more node_access module, rebuilding will be
284
285
286
287
  // straightforward, we can do it right now.
  if (node_access_needs_rebuild() && count(module_implements('node_grants')) == 0) {
    node_access_rebuild();
  }
Steven Wittens's avatar
Steven Wittens committed
288
289
}

290
291
/**
 * @defgroup hooks Hooks
Dries's avatar
   
Dries committed
292
293
 * @{
 * Allow modules to interact with the Drupal core.
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
322
 *
 * 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) {
323
324
325
326
327
328
329
  $function = $module . '_' . $hook;
  if (defined('MAINTENANCE_MODE')) {
    return function_exists($function);
  }
  else {
    return drupal_function_exists($function);
  }
330
331
}

Dries's avatar
   
Dries committed
332
333
334
335
/**
 * Determine which modules are implementing a hook.
 *
 * @param $hook
336
337
 *   The name of the hook (e.g. "help" or "menu"). Special cases:
 *     MODULE_IMPLEMENTS_CLEAR_CACHE: Force the stored list of hook
338
 *   implementations to be regenerated (such as after enabling a new module,
339
340
341
342
 *     before processing hook_enable).
 *     MODULE_IMPLEMENTS_WRITE_CACHE: Write the stored list of hook
 *     implementations into the cache_registry table.
 * @param $sort
343
 *   By default, modules are ordered by weight and module name. By setting this
344
 *   option to TRUE, modules will be ordered by module name.
Dries's avatar
   
Dries committed
345
346
 * @return
 *   An array with the names of the modules which are implementing this hook.
347
348
 *   All enabled modules are taken into consideration and the files containing
 *   the implementations are loaded as necessary.
Dries's avatar
   
Dries committed
349
 */
350
351
function module_implements($hook, $sort = FALSE) {
  static $implementations = array(), $sorted_implementations = array(), $loaded = array(), $cached_hooks = 0;
Dries's avatar
   
Dries committed
352

353
354
  if (defined('MAINTENANCE_MODE')) {
    return _module_implements_maintenance($hook, $sort);
355
  }
356
  if ($hook === MODULE_IMPLEMENTS_CLEAR_CACHE) {
357
    $implementations = array();
358
359
360
361
362
    $sorted_implementations = array();
    $loaded = array();
    $cached_hooks = 0;
    cache_clear_all('hooks', 'cache_registry');
    return;
363
  }
364
365
366
367
368
369
  if ($hook === MODULE_IMPLEMENTS_WRITE_CACHE) {
    // Only write this to cache if we loaded new implementations.
    if (count($implementations) > $cached_hooks) {
      cache_set('hooks', $implementations, 'cache_registry');
    }
    return;
370
371
  }

372
373
374
375
376
  if (!isset($loaded[$hook])) {
    if (empty($implementations) && ($cache = cache_get('hooks', 'cache_registry'))) {
      $implementations = $cache->data;
      $cached_hooks = count($implementations);
    }
377
    if (!isset($implementations[$hook])) {
378
379
380
381
382
      // The module name (rather than the filename) is used as the fallback
      // weighting in order to guarantee consistent behavior across different
      // Drupal installations, which might have modules installed in different
      // locations in the file system. The ordering here must also be
      // consistent with the one used in module_list().
383
384
385
386
387
388
      $implementations[$hook] = db_query("SELECT module FROM {registry} WHERE type = 'function' AND suffix = :hook ORDER BY weight, module", array(':hook' => $hook))->fetchCol();
    }
    foreach ($implementations[$hook] as $module) {
      $function = $module . '_' . $hook;
      if (!function_exists($function)) {
        drupal_function_exists($function);
Dries's avatar
   
Dries committed
389
390
      }
    }
391
392
    $loaded[$hook] = TRUE;
  }
Dries's avatar
   
Dries committed
393

394
395
396
397
398
399
400
401
  if ($sort) {
    if (!isset($sorted_implementations[$hook])) {
      $sorted_implementations[$hook] = $implementations[$hook];
      sort($sorted_implementations[$hook]);
    }
    return $sorted_implementations[$hook];
  }
  else {
402
403
    return $implementations[$hook];
  }
Dries's avatar
   
Dries committed
404
405
}

406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
/**
 * This is the maintenance version of module_implements for internal use only.
 *
 * This function is called whenever MAINTENANCE_MODE is defined and is a
 * safe code path for Drupal installation or upgrade because it does not use
 * the database, instead it uses module_list. @see module_list $fixed_list on
 * how to make module_list also DB independent.
 *
 * @param $hook
 *   The name of the hook (e.g. "help" or "menu").
 * @param $sort
 *   By default, modules are ordered by weight and filename, settings this
 *   option to TRUE, module list will be ordered by module name.
 * @return
 *   An array with the names of the modules which are implementing this hook.
 *   Only enabled and already loaded modules are taken into consideration.
 */
function _module_implements_maintenance($hook, $sort = FALSE) {
  $implementations = array();
  foreach (module_list() as $module) {
    $function = $module . '_' . $hook;
    if (function_exists($function)) {
      $implementations[] = $module;
    }
    if ($sort) {
      sort($implementations);
    }
  }
  return $implementations;
}

437
438
439
440
441
442
443
444
445
446
447
448
/**
 * 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.
 */
449
450
function module_invoke() {
  $args = func_get_args();
451
452
453
  $module = $args[0];
  $hook = $args[1];
  unset($args[0], $args[1]);
454
  if (module_hook($module, $hook)) {
455
    return call_user_func_array($module . '_' . $hook, $args);
456
457
458
459
460
461
462
463
464
465
466
467
468
  }
}
/**
 * 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.
 */
469
470
function module_invoke_all() {
  $args = func_get_args();
471
472
  $hook = $args[0];
  unset($args[0]);
473
  $return = array();
474
  foreach (module_implements($hook) as $module) {
475
    $function = $module . '_' . $hook;
476
477
478
479
480
    if (drupal_function_exists($function)) {
      $result = call_user_func_array($function, $args);
      if (isset($result) && is_array($result)) {
        $return = array_merge_recursive($return, $result);
      }
481
      elseif (isset($result)) {
482
483
        $return[] = $result;
      }
484
    }
485
486
487
488
489
490
  }

  return $return;
}

/**
Dries's avatar
   
Dries committed
491
 * @} End of "defgroup hooks".
492
493
 */

494
495
496
497
/**
 * Array of modules required by core.
 */
function drupal_required_modules() {
498
499
500
  $files = drupal_system_listing('/\.info$/', 'modules', 'name', 0);
  $required = array();
  foreach ($files as $name => $file) {
501
    $info = drupal_parse_info_file($file->filepath);
502
503
504
505
506
    if (!empty($info) && !empty($info['required']) && $info['required']) {
      $required[] = $name;
    }
  }
  return $required;
507
}