1 <?php

     2 

     3 /**

     4  * @file

     5  * Hooks for file module.

     6  */

     7 

     8 /**

     9  * Control download access to files.

    10  *

    11  * The hook is typically implemented to limit access based on the entity the

    12  * file is referenced, e.g., only users with access to a node should be allowed

    13  * to download files attached to that node.

    14  *

    15  * @param array $file_item

    16  *   The array of information about the file to check access for.

    17  * @param $entity_type

    18  *   The type of $entity; for example, 'node' or 'user'.

    19  * @param $entity

    20  *   The $entity to which $file is referenced.

    21  *

    22  * @return

    23  *   TRUE is access should be allowed by this entity or FALSE if denied. Note

    24  *   that denial may be overridden by another entity controller, making this

    25  *   grant permissive rather than restrictive.

    26  *

    27  * @see hook_field_access().

    28  */

    29 function hook_file_download_access($file_item, $entity_type, $entity) {

    30   if ($entity_type == 'node') {

    31     return node_access('view', $entity);

    32   }

    33 }

    34 

    35 /**

    36  * Alter the access rules applied to a file download.

    37  *

    38  * Entities that implement file management set the access rules for their

    39  * individual files. Module may use this hook to create custom access rules

    40  * for file downloads.

    41  *

    42  * @see hook_file_download_access().

    43  *

    44  * @param $grants

    45  *   An array of grants gathered by hook_file_download_access(). The array is

    46  *   keyed by the module that defines the entity type's access control; the

    47  *   values are Boolean grant responses for each module.

    48  * @param array $file_item

    49  *   The array of information about the file to alter access for.

    50  * @param $entity_type

    51  *   The type of $entity; for example, 'node' or 'user'.

    52  * @param $entity

    53  *   The $entity to which $file is referenced.

    54  */

    55 function hook_file_download_access_alter(&$grants, $file_item, $entity_type, $entity) {

    56   // For our example module, we always enforce the rules set by node module.

    57   if (isset($grants['node'])) {

    58     $grants = array('node' => $grants['node']);

    59   }

    60 }