Club Drupal

<?php

/**

 * @file

 * This is the main script for the Field Permissions module. It merely contains

 * the implementation of hooks invoked by Drupal core and CCK.

 * All common functions are externalized into several scripts that are included

 * on demand to save memory consumption during normal site operation.

 */

/**

 * Indicates that a field does not have any access control.

 */

define('FIELD_PERMISSIONS_PUBLIC', 0);

/**

 * Indicates that a field is private.

 *

 * Private fields are never displayed, and are only editable by the author (and

 * by site administrators with the 'access private fields' permission).

 */

define('FIELD_PERMISSIONS_PRIVATE', 1);

/**

 * Indicates that a field has custom permissions.

 */

define('FIELD_PERMISSIONS_CUSTOM', 2);

/**

 * Implements hook_help().

 */

function field_permissions_help($path, $arg) {

  switch ($path) {

    // Main module help for the Field Permissions module.

    case 'admin/help#field_permissions':

      return '<p>' . t('Set field-level permissions to edit or view CCK fields in any node, edit field during node creation, and edit or view permissions for nodes owned by the current user.') . '</p>';

    // Help for the Field Permissions overview page.

    case 'admin/reports/fields/permissions':

      return '<p>' . t('Report and troubleshoot field permissions.') . '</p>';

  }

}

/**

 * Implements hook_menu().

 */

function field_permissions_menu() {

  $items['admin/reports/fields/list'] = array(

    'title' => 'List',

    'type' => MENU_DEFAULT_LOCAL_TASK,

    'weight' => -10,

  );

  $items['admin/reports/fields/permissions'] = array(

    'title' => 'Permissions',

    'description' => 'Report and troubleshoot field permissions.',

    'page callback' => 'field_permissions_overview',

    'access arguments' => array('administer field permissions'),

    'file' => 'field_permissions.admin.inc',

    'type' => MENU_LOCAL_TASK,

    'weight' => 0,

  );

  return $items;

}

/**

 * Implementation of hook_permission().

 */

function field_permissions_permission() {

  module_load_include('inc', 'field_permissions', 'field_permissions.admin');

  return _field_permissions_permission();

}

/**

 * Implements of hook_form_FORM_ID_alter().

 */

function field_permissions_form_field_ui_field_edit_form_alter(&$form, &$form_state, $form_id) {

  // Injects the Field Permissions settings on the Edit field tab.

  form_load_include($form_state, 'inc', 'field_permissions', 'field_permissions.admin');

  return _field_permissions_field_settings_form_alter($form, $form_state, $form_id);

}

/**

 * Implementation of hook_field_access().

 *

 * @param $op

 *   The operation to be performed. Possible values:

 *   - 'edit'

 *   - 'view'

 * @param $field

 *   The field on which the operation is to be performed.

 * @param $entity_type

 *   The type of entity; e.g. 'node' or 'user'.

 * @param $entity

 *   The entity on which the operation is to be performed.

 * @param $account

 *   The account to check.

 *

 * @return

 *   FALSE if the operation is not allowed.

 *   Note when field_access() is invoked, access is granted unless one

 *   implementation of hook_field_access() explicitly returns FALSE.

 *

 * @see field_access()

 */

function field_permissions_field_access($op, $field, $entity_type, $entity, $account) {

  // Ignore the request if permissions have not been enabled for this field.

  if (!isset($field['field_permissions']['type']) || $field['field_permissions']['type'] == FIELD_PERMISSIONS_PUBLIC) {

    return;

  }

  // If the field is private, then only the author (and administrators with the

  // 'access private fields' permissions) can view and edit it.

  elseif ($field['field_permissions']['type'] == FIELD_PERMISSIONS_PRIVATE) {

    if (isset($entity)) {

      return _field_permissions_entity_is_owned_by_account($entity, $account) || user_access('access private fields', $account);

    }

    // If the entity does not exist, we must check if there is access to any

    // entity; see comments in field_permissions_empty_entity_access(). In this

    // case that will always be true, since private fields are always editable

    // by their authors and in theory any user account can be the author of

    // some entity on the site.

    else {

      return TRUE;

    }

  }

  // Otherwise, check access by permission.

  elseif ($field['field_permissions']['type'] == FIELD_PERMISSIONS_CUSTOM) {

    if (!isset($entity)) {

      return field_permissions_empty_entity_access($op, $field['field_name'], $account);

    }

    elseif ($op == 'view') {

      return _field_permissions_field_view_access($field['field_name'], $entity_type, $entity, $account);

    }

    elseif ($op == 'edit') {

      return _field_permissions_field_edit_access($field['field_name'], $entity_type, $entity, $account);

    }

  }

}

/**

 * Determines custom field permissions access when the entity is unknown.

 *

 * When a module calls field_access() without providing an entity (which the

 * API allows it to do), it is doing so in order to check generic access to the

 * field. Therefore, we should only deny access if we know that there is no

 * entity anywhere on the site for which the user has access to the provided

 * field.

 *

 * For example, Views calls field_access('view') without providing the entity,

 * in order to determine if the field can be included in the query itself. So

 * we only want to return FALSE if we know that there are no entities for which

 * access will be granted. Later on, Views will invoke field_access('view')

 * again, indirectly, when rendering the fields using field_view_field(), and

 * at that point the entity will be passed along so we can do our normal checks

 * on it.

 *

 * As another example, the FileField Sources module uses field_access('edit')

 * as a menu access callback for the IMCE file browser and does not pass along

 * the entity. So we must return TRUE here if there is any entity for which the

 * user is allowed to edit the field (otherwise the user would not have access

 * to the IMCE file browser interface when editing the fields they do have

 * permission to edit).

 *

 * @param $op

 *   The operation to be performed ('view' or 'edit').

 * @param $field_name

 *   The name of the field whose access is being checked.

 * @param $account

 *   The user account whose access is being checked.

 *

 * @return

 *   TRUE if access should be allowed, or FALSE if it shouln't.

 */

function field_permissions_empty_entity_access($op, $field_name, $account) {

  $all_permissions['view'] = array(

    'view ' . $field_name,

    'view own ' . $field_name,

  );

  $all_permissions['edit'] = array(

    'create ' . $field_name,

    'edit ' . $field_name,

    'edit own ' . $field_name,

  );

  // If there's any scenario where the user might have permission to perform

  // the operation on the field, return TRUE.

  if (isset($all_permissions[$op])) {

    foreach ($all_permissions[$op] as $permission) {

      if (user_access($permission, $account)) {

        return TRUE;

      }

    }

  }

  return FALSE;

}

/**

 * Implementation of hook_field_access('view').

 */

function _field_permissions_field_view_access($field_name, $entity_type, $entity, $account) {

  // Check if user has access to view this field in any entity.

  if (user_access('view ' . $field_name, $account)) {

    return TRUE;

  }

  // If the user has permission to view entities that they own, return TRUE if

  // they own this entity or FALSE if they don't.

  if (user_access('view own ' . $field_name, $account)) {

    return _field_permissions_entity_is_owned_by_account($entity, $account);

  }

  return FALSE;

}

/**

 * Implementation of hook_field_access('edit').

 */

function _field_permissions_field_edit_access($field_name, $entity_type, $entity, $account) {

  // If this is a new entity, check if the user has access to edit the field on

  // entity creation.

  if (isset($entity->is_new)) {

    // Some entities provide an "is_new" property. If that is present, respect

    // whatever it's set to.

    $is_new = $entity->is_new;

  }

  else {

    // Otherwise, try to find out if the entity is new by checking its ID. Note

    // that checking empty() rather than !isset() is important here, to deal

    // with the case of entities that store "0" as their ID while the final

    // entity is in the process of being created (user accounts are a good

    // example of this).

    list($id, $vid, $bundle) = entity_extract_ids($entity_type, $entity);

    $is_new = empty($id);

  }

  if ($is_new) {

    return user_access('create ' . $field_name, $account);

  }

  // Check if user has access to edit this field in any entity.

  if (user_access('edit ' . $field_name, $account)) {

    return TRUE;

  }

  // If the user has permission to edit entities that they own, return TRUE if

  // they own this entity or FALSE if they don't.

  if (user_access('edit own ' . $field_name, $account)) {

    return _field_permissions_entity_is_owned_by_account($entity, $account);

  }

  return FALSE;

}

/**

 * Returns TRUE if an entity is owned by a user account, FALSE otherwise.

 */

function _field_permissions_entity_is_owned_by_account($entity, $account) {

  // Try to get the uid of the entity owner from the entity itself. If it's not

  // set (for example, if the entity type does not store a uid or does not have

  // a concept of "ownership"), we need to assume that the provided user

  // account does not own it.

  return isset($entity->uid) && $entity->uid == $account->uid;

}