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   1  <?php
   2  // $Id: block.module,v 1.299.2.4 2009/10/06 12:13:01 goba Exp $
   3  
   4  /**
   5   * @file
   6   * Controls the boxes that are displayed around the main content.
   7   */
   8  
   9  /**
  10   * Denotes that a block is not enabled in any region and should not
  11   * be shown.
  12   */
  13  define('BLOCK_REGION_NONE', -1);
  14  
  15  /**
  16   * Constants defining cache granularity for blocks.
  17   *
  18   * Modules specify the caching patterns for their blocks using binary
  19   * combinations of these constants in their hook_block(op 'list'):
  20   *   $block[delta]['cache'] = BLOCK_CACHE_PER_ROLE | BLOCK_CACHE_PER_PAGE;
  21   * BLOCK_CACHE_PER_ROLE is used as a default when no caching pattern is
  22   * specified.
  23   *
  24   * The block cache is cleared in cache_clear_all(), and uses the same clearing
  25   * policy than page cache (node, comment, user, taxonomy added or updated...).
  26   * Blocks requiring more fine-grained clearing might consider disabling the
  27   * built-in block cache (BLOCK_NO_CACHE) and roll their own.
  28   *
  29   * Note that user 1 is excluded from block caching.
  30   */
  31  
  32  /**
  33   * The block should not get cached. This setting should be used:
  34   * - for simple blocks (notably those that do not perform any db query),
  35   * where querying the db cache would be more expensive than directly generating
  36   * the content.
  37   * - for blocks that change too frequently.
  38   */
  39  define('BLOCK_NO_CACHE', -1);
  40  
  41  /**
  42   * The block can change depending on the roles the user viewing the page belongs to.
  43   * This is the default setting, used when the block does not specify anything.
  44   */
  45  define('BLOCK_CACHE_PER_ROLE', 0x0001);
  46  
  47  /**
  48   * The block can change depending on the user viewing the page.
  49   * This setting can be resource-consuming for sites with large number of users,
  50   * and thus should only be used when BLOCK_CACHE_PER_ROLE is not sufficient.
  51   */
  52  define('BLOCK_CACHE_PER_USER', 0x0002);
  53  
  54  /**
  55   * The block can change depending on the page being viewed.
  56   */
  57  define('BLOCK_CACHE_PER_PAGE', 0x0004);
  58  
  59  /**
  60   * The block is the same for every user on every page where it is visible.
  61   */
  62  define('BLOCK_CACHE_GLOBAL', 0x0008);
  63  
  64  /**
  65   * Implementation of hook_help().
  66   */
  67  function block_help($path, $arg) {
  68    switch ($path) {
  69      case 'admin/help#block':
  70        $output = '<p>'. t('Blocks are boxes of content rendered into an area, or region, of a web page. The default theme Garland, for example, implements the regions "left sidebar", "right sidebar", "content", "header", and "footer", and a block may appear in any one of these areas. The <a href="@blocks">blocks administration page</a> provides a drag-and-drop interface for assigning a block to a region, and for controlling the order of blocks within regions.', array('@blocks' => url('admin/build/block'))) .'</p>';
  71        $output .= '<p>'. t('Although blocks are usually generated automatically by modules (like the <em>User login</em> block, for example), administrators can also define custom blocks. Custom blocks have a title, description, and body. The body of the block can be as long as necessary, and can contain content supported by any available <a href="@input-format">input format</a>.', array('@input-format' => url('admin/settings/filters'))) .'</p>';
  72        $output .= '<p>'. t('When working with blocks, remember that:') .'</p>';
  73        $output .= '<ul><li>'. t('since not all themes implement the same regions, or display regions in the same way, blocks are positioned on a per-theme basis.') .'</li>';
  74        $output .= '<li>'. t('disabled blocks, or blocks not in a region, are never shown.') .'</li>';
  75        $output .= '<li>'. t('when throttle module is enabled, throttled blocks (blocks with the <em>Throttle</em> checkbox selected) are hidden during high server loads.') .'</li>';
  76        $output .= '<li>'. t('blocks can be configured to be visible only on certain pages.') .'</li>';
  77        $output .= '<li>'. t('blocks can be configured to be visible only when specific conditions are true.') .'</li>';
  78        $output .= '<li>'. t('blocks can be configured to be visible only for certain user roles.') .'</li>';
  79        $output .= '<li>'. t('when allowed by an administrator, specific blocks may be enabled or disabled on a per-user basis using the <em>My account</em> page.') .'</li>';
  80        $output .= '<li>'. t('some dynamic blocks, such as those generated by modules, will be displayed only on certain pages.') .'</li></ul>';
  81        $output .= '<p>'. t('For more information, see the online handbook entry for <a href="@block">Block module</a>.', array('@block' => 'http://drupal.org/handbook/modules/block/')) .'</p>';
  82        return $output;
  83      case 'admin/build/block':
  84        $throttle = module_exists('throttle');
  85        $output = '<p>'. t('This page provides a drag-and-drop interface for assigning a block to a region, and for controlling the order of blocks within regions. To change the region or order of a block, grab a drag-and-drop handle under the <em>Block</em> column and drag the block to a new location in the list. (Grab a handle by clicking and holding the mouse while hovering over a handle icon.) Since not all themes implement the same regions, or display regions in the same way, blocks are positioned on a per-theme basis. Remember that your changes will not be saved until you click the <em>Save blocks</em> button at the bottom of the page.') .'</p>';
  86        if ($throttle) {
  87          $output .= '<p>'. t('To reduce CPU usage, database traffic or bandwidth, blocks may be automatically disabled during high server loads by selecting their <em>Throttle</em> checkbox. Adjust throttle thresholds on the <a href="@throttleconfig">throttle configuration page</a>.', array('@throttleconfig' => url('admin/settings/throttle'))) .'</p>';
  88        }
  89        $output .= '<p>'. t('Click the <em>configure</em> link next to each block to configure its specific title and visibility settings. Use the <a href="@add-block">add block page</a> to create a custom block.', array('@add-block' => url('admin/build/block/add'))) .'</p>';
  90        return $output;
  91      case 'admin/build/block/add':
  92        return '<p>'. t('Use this page to create a new custom block. New blocks are disabled by default, and must be moved to a region on the <a href="@blocks">blocks administration page</a> to be visible.', array('@blocks' => url('admin/build/block'))) .'</p>';
  93    }
  94  }
  95  
  96  /**
  97   * Implementation of hook_theme()
  98   */
  99  function block_theme() {
 100    return array(
 101      'block_admin_display_form' => array(
 102        'template' => 'block-admin-display-form',
 103        'file' => 'block.admin.inc',
 104        'arguments' => array('form' => NULL),
 105      ),
 106    );
 107  }
 108  
 109  /**
 110   * Implementation of hook_perm().
 111   */
 112  function block_perm() {
 113    return array('administer blocks', 'use PHP for block visibility');
 114  }
 115  
 116  /**
 117   * Implementation of hook_menu().
 118   */
 119  function block_menu() {
 120    $items['admin/build/block'] = array(
 121      'title' => 'Blocks',
 122      'description' => 'Configure what block content appears in your site\'s sidebars and other regions.',
 123      'page callback' => 'block_admin_display',
 124      'access arguments' => array('administer blocks'),
 125      'file' => 'block.admin.inc',
 126    );
 127    $items['admin/build/block/list'] = array(
 128      'title' => 'List',
 129      'type' => MENU_DEFAULT_LOCAL_TASK,
 130      'weight' => -10,
 131    );
 132    $items['admin/build/block/list/js'] = array(
 133      'title' => 'JavaScript List Form',
 134      'page callback' => 'block_admin_display_js',
 135      'access arguments' => array('administer blocks'),
 136      'type' => MENU_CALLBACK,
 137      'file' => 'block.admin.inc',
 138    );
 139    $items['admin/build/block/configure'] = array(
 140      'title' => 'Configure block',
 141      'page callback' => 'drupal_get_form',
 142      'page arguments' => array('block_admin_configure'),
 143      'access arguments' => array('administer blocks'),
 144      'type' => MENU_CALLBACK,
 145      'file' => 'block.admin.inc',
 146    );
 147    $items['admin/build/block/delete'] = array(
 148      'title' => 'Delete block',
 149      'page callback' => 'drupal_get_form',
 150      'page arguments' => array('block_box_delete'),
 151      'access arguments' => array('administer blocks'),
 152      'type' => MENU_CALLBACK,
 153      'file' => 'block.admin.inc',
 154    );
 155    $items['admin/build/block/add'] = array(
 156      'title' => 'Add block',
 157      'page callback' => 'drupal_get_form',
 158      'page arguments' => array('block_add_block_form'),
 159      'access arguments' => array('administer blocks'),
 160      'type' => MENU_LOCAL_TASK,
 161      'file' => 'block.admin.inc',
 162    );
 163    $default = variable_get('theme_default', 'garland');
 164    foreach (list_themes() as $key => $theme) {
 165      $items['admin/build/block/list/'. $key] = array(
 166        'title' => check_plain($theme->info['name']),
 167        'page arguments' => array($key),
 168        'type' => $key == $default ? MENU_DEFAULT_LOCAL_TASK : MENU_LOCAL_TASK,
 169        'weight' => $key == $default ? -10 : 0,
 170        'file' => 'block.admin.inc',
 171        'access callback' => '_block_themes_access',
 172        'access arguments' => array($theme),
 173      );
 174    }
 175    return $items;
 176  }
 177  
 178  /**
 179   * Menu item access callback - only admin or enabled themes can be accessed
 180   */
 181  function _block_themes_access($theme) {
 182    return user_access('administer blocks') && ($theme->status || $theme->name == variable_get('admin_theme', '0'));
 183  }
 184  
 185  /**
 186   * Implementation of hook_block().
 187   *
 188   * Generates the administrator-defined blocks for display.
 189   */
 190  function block_block($op = 'list', $delta = 0, $edit = array()) {
 191    switch ($op) {
 192      case 'list':
 193        $blocks = array();
 194  
 195        $result = db_query('SELECT bid, info FROM {boxes} ORDER BY info');
 196        while ($block = db_fetch_object($result)) {
 197          $blocks[$block->bid]['info'] = $block->info;
 198          // Not worth caching.
 199          $blocks[$block->bid]['cache'] = BLOCK_NO_CACHE;
 200        }
 201        return $blocks;
 202  
 203      case 'configure':
 204        $box = array('format' => FILTER_FORMAT_DEFAULT);
 205        if ($delta) {
 206          $box = block_box_get($delta);
 207        }
 208        if (filter_access($box['format'])) {
 209          return block_box_form($box);
 210        }
 211        break;
 212  
 213      case 'save':
 214        block_box_save($edit, $delta);
 215        break;
 216  
 217      case 'view':
 218        $block = db_fetch_object(db_query('SELECT body, format FROM {boxes} WHERE bid = %d', $delta));
 219        $data['content'] = check_markup($block->body, $block->format, FALSE);
 220        return $data;
 221    }
 222  }
 223  
 224  /**
 225   * Update the 'blocks' DB table with the blocks currently exported by modules.
 226   *
 227   * @return
 228   *   Blocks currently exported by modules.
 229   */
 230  function _block_rehash() {
 231    global $theme_key;
 232  
 233    init_theme();
 234  
 235    $result = db_query("SELECT * FROM {blocks} WHERE theme = '%s'", $theme_key);
 236    $old_blocks = array();
 237    while ($old_block = db_fetch_array($result)) {
 238      $old_blocks[$old_block['module']][$old_block['delta']] = $old_block;
 239    }
 240  
 241    $blocks = array();
 242    // Valid region names for the theme.
 243    $regions = system_region_list($theme_key);
 244  
 245    foreach (module_list() as $module) {
 246      $module_blocks = module_invoke($module, 'block', 'list');
 247      if ($module_blocks) {
 248        foreach ($module_blocks as $delta => $block) {
 249          if (empty($old_blocks[$module][$delta])) {
 250            // If it's a new block, add identifiers.
 251            $block['module'] = $module;
 252            $block['delta']  = $delta;
 253            $block['theme']  = $theme_key;
 254            if (!isset($block['pages'])) {
 255              // {block}.pages is type 'text', so it cannot have a
 256              // default value, and not null, so we need to provide
 257              // value if the module did not.
 258              $block['pages']  = '';
 259            }
 260            // Add defaults and save it into the database.
 261            drupal_write_record('blocks', $block);
 262            // Set region to none if not enabled.
 263            $block['region'] = $block['status'] ? $block['region'] : BLOCK_REGION_NONE;
 264            // Add to the list of blocks we return.
 265            $blocks[] = $block;
 266          }
 267          else {
 268            // If it's an existing block, database settings should overwrite
 269            // the code. But aside from 'info' everything that's definable in
 270            // code is stored in the database and we do not store 'info', so we
 271            // do not need to update the database here.
 272            // Add 'info' to this block.
 273            $old_blocks[$module][$delta]['info'] = $block['info'];
 274            // If the region name does not exist, disable the block and assign it to none.
 275            if (!empty($old_blocks[$module][$delta]['region']) && !isset($regions[$old_blocks[$module][$delta]['region']])) {
 276              drupal_set_message(t('The block %info was assigned to the invalid region %region and has been disabled.', array('%info' => $old_blocks[$module][$delta]['info'], '%region' => $old_blocks[$module][$delta]['region'])), 'warning');
 277              $old_blocks[$module][$delta]['status'] = 0;
 278              $old_blocks[$module][$delta]['region'] = BLOCK_REGION_NONE;
 279            }
 280            else {
 281              $old_blocks[$module][$delta]['region'] = $old_blocks[$module][$delta]['status'] ? $old_blocks[$module][$delta]['region'] : BLOCK_REGION_NONE;
 282            }
 283            // Add this block to the list of blocks we return.
 284            $blocks[] = $old_blocks[$module][$delta];
 285            // Remove this block from the list of blocks to be deleted.
 286            unset($old_blocks[$module][$delta]);
 287          }
 288        }
 289      }
 290    }
 291  
 292    // Remove blocks that are no longer defined by the code from the database.
 293    foreach ($old_blocks as $module => $old_module_blocks) {
 294      foreach ($old_module_blocks as $delta => $block) {
 295        db_query("DELETE FROM {blocks} WHERE module = '%s' AND delta = '%s' AND theme = '%s'", $module, $delta, $theme_key);
 296      }
 297    }
 298    return $blocks;
 299  }
 300  
 301  /**
 302   * Returns information from database about a user-created (custom) block.
 303   *
 304   * @param $bid
 305   *   ID of the block to get information for.
 306   * @return
 307   *   Associative array of information stored in the database for this block.
 308   *   Array keys:
 309   *   - bid: Block ID.
 310   *   - info: Block description.
 311   *   - body: Block contents.
 312   *   - format: Filter ID of the filter format for the body.
 313   */
 314  function block_box_get($bid) {
 315    return db_fetch_array(db_query("SELECT * FROM {boxes} WHERE bid = %d", $bid));
 316  }
 317  
 318  /**
 319   * Define the custom block form.
 320   */
 321  function block_box_form($edit = array()) {
 322    $edit += array(
 323      'info' => '',
 324      'body' => '',
 325    );
 326    $form['info'] = array(
 327      '#type' => 'textfield',
 328      '#title' => t('Block description'),
 329      '#default_value' => $edit['info'],
 330      '#maxlength' => 64,
 331      '#description' => t('A brief description of your block. Used on the <a href="@overview">block overview page</a>.', array('@overview' => url('admin/build/block'))),
 332      '#required' => TRUE,
 333      '#weight' => -19,
 334    );
 335    $form['body_field']['#weight'] = -17;
 336    $form['body_field']['body'] = array(
 337      '#type' => 'textarea',
 338      '#title' => t('Block body'),
 339      '#default_value' => $edit['body'],
 340      '#rows' => 15,
 341      '#description' => t('The content of the block as shown to the user.'),
 342      '#weight' => -17,
 343    );
 344    if (!isset($edit['format'])) {
 345      $edit['format'] = FILTER_FORMAT_DEFAULT;
 346    }
 347    $form['body_field']['format'] = filter_form($edit['format'], -16);
 348  
 349    return $form;
 350  }
 351  
 352  /**
 353   * Saves a user-created block in the database.
 354   *
 355   * @param $edit
 356   *   Associative array of fields to save. Array keys:
 357   *   - info: Block description.
 358   *   - body: Block contents.
 359   *   - format: Filter ID of the filter format for the body.
 360   * @param $delta
 361   *   Block ID of the block to save.
 362   * @return
 363   *   Always returns TRUE.
 364   */
 365  function block_box_save($edit, $delta) {
 366    if (!filter_access($edit['format'])) {
 367      $edit['format'] = FILTER_FORMAT_DEFAULT;
 368    }
 369  
 370    db_query("UPDATE {boxes} SET body = '%s', info = '%s', format = %d WHERE bid = %d", $edit['body'], $edit['info'], $edit['format'], $delta);
 371  
 372    return TRUE;
 373  }
 374  
 375  /**
 376   * Implementation of hook_user().
 377   *
 378   * Allow users to decide which custom blocks to display when they visit
 379   * the site.
 380   */
 381  function block_user($type, $edit, &$account, $category = NULL) {
 382    switch ($type) {
 383      case 'form':
 384        if ($category == 'account') {
 385          $rids = array_keys($account->roles);
 386          $result = db_query("SELECT DISTINCT b.* FROM {blocks} b LEFT JOIN {blocks_roles} r ON b.module = r.module AND b.delta = r.delta WHERE b.status = 1 AND b.custom != 0 AND (r.rid IN (". db_placeholders($rids) .") OR r.rid IS NULL) ORDER BY b.weight, b.module", $rids);
 387          $form['block'] = array('#type' => 'fieldset', '#title' => t('Block configuration'), '#weight' => 3, '#collapsible' => TRUE, '#tree' => TRUE);
 388          while ($block = db_fetch_object($result)) {
 389            $data = module_invoke($block->module, 'block', 'list');
 390            if ($data[$block->delta]['info']) {
 391              $return = TRUE;
 392              $form['block'][$block->module][$block->delta] = array('#type' => 'checkbox', '#title' => check_plain($data[$block->delta]['info']), '#default_value' => isset($account->block[$block->module][$block->delta]) ? $account->block[$block->module][$block->delta] : ($block->custom == 1));
 393            }
 394          }
 395  
 396          if (!empty($return)) {
 397            return $form;
 398          }
 399        }
 400  
 401        break;
 402      case 'validate':
 403        if (empty($edit['block'])) {
 404          $edit['block'] = array();
 405        }
 406        return $edit;
 407    }
 408  }
 409  
 410  /**
 411   * Return all blocks in the specified region for the current user.
 412   *
 413   * @param $region
 414   *   The name of a region.
 415   *
 416   * @return
 417   *   An array of block objects, indexed with <i>module</i>_<i>delta</i>.
 418   *   If you are displaying your blocks in one or two sidebars, you may check
 419   *   whether this array is empty to see how many columns are going to be
 420   *   displayed.
 421   *
 422   * @todo
 423   *   Now that the blocks table has a primary key, we should use that as the
 424   *   array key instead of <i>module</i>_<i>delta</i>.
 425   */
 426  function block_list($region) {
 427    global $user, $theme_key;
 428  
 429    static $blocks = array();
 430  
 431    if (!count($blocks)) {
 432      $rids = array_keys($user->roles);
 433      $result = db_query(db_rewrite_sql("SELECT DISTINCT b.* FROM {blocks} b LEFT JOIN {blocks_roles} r ON b.module = r.module AND b.delta = r.delta WHERE b.theme = '%s' AND b.status = 1 AND (r.rid IN (". db_placeholders($rids) .") OR r.rid IS NULL) ORDER BY b.region, b.weight, b.module", 'b', 'bid'), array_merge(array($theme_key), $rids));
 434      while ($block = db_fetch_object($result)) {
 435        if (!isset($blocks[$block->region])) {
 436          $blocks[$block->region] = array();
 437        }
 438        // Use the user's block visibility setting, if necessary
 439        if ($block->custom != 0) {
 440          if ($user->uid && isset($user->block[$block->module][$block->delta])) {
 441            $enabled = $user->block[$block->module][$block->delta];
 442          }
 443          else {
 444            $enabled = ($block->custom == 1);
 445          }
 446        }
 447        else {
 448          $enabled = TRUE;
 449        }
 450  
 451        // Match path if necessary
 452        if ($block->pages) {
 453          if ($block->visibility < 2) {
 454            $path = drupal_get_path_alias($_GET['q']);
 455            // Compare with the internal and path alias (if any).
 456            $page_match = drupal_match_path($path, $block->pages);
 457            if ($path != $_GET['q']) {
 458              $page_match = $page_match || drupal_match_path($_GET['q'], $block->pages);
 459            }
 460            // When $block->visibility has a value of 0, the block is displayed on
 461            // all pages except those listed in $block->pages. When set to 1, it
 462            // is displayed only on those pages listed in $block->pages.
 463            $page_match = !($block->visibility xor $page_match);
 464          }
 465          else {
 466            $page_match = drupal_eval($block->pages);
 467          }
 468        }
 469        else {
 470          $page_match = TRUE;
 471        }
 472        $block->enabled = $enabled;
 473        $block->page_match = $page_match;
 474        $blocks[$block->region]["{$block->module}_{$block->delta}"] = $block;
 475      }
 476    }
 477  
 478    // Create an empty array if there were no entries
 479    if (!isset($blocks[$region])) {
 480      $blocks[$region] = array();
 481    }
 482  
 483    foreach ($blocks[$region] as $key => $block) {
 484      // Render the block content if it has not been created already.
 485      if (!isset($block->content)) {
 486        // Erase the block from the static array - we'll put it back if it has content.
 487        unset($blocks[$region][$key]);
 488        if ($block->enabled && $block->page_match) {
 489          // Check the current throttle status and see if block should be displayed
 490          // based on server load.
 491          if (!($block->throttle && (module_invoke('throttle', 'status') > 0))) {
 492            // Try fetching the block from cache. Block caching is not compatible with
 493            // node_access modules. We also preserve the submission of forms in blocks,
 494            // by fetching from cache only if the request method is 'GET'.
 495            if (!count(module_implements('node_grants')) && $_SERVER['REQUEST_METHOD'] == 'GET' && ($cid = _block_get_cache_id($block)) && ($cache = cache_get($cid, 'cache_block'))) {
 496              $array = $cache->data;
 497            }
 498            else {
 499              $array = module_invoke($block->module, 'block', 'view', $block->delta);
 500              if (isset($cid)) {
 501                cache_set($cid, $array, 'cache_block', CACHE_TEMPORARY);
 502              }
 503            }
 504  
 505            if (isset($array) && is_array($array)) {
 506              foreach ($array as $k => $v) {
 507                $block->$k = $v;
 508              }
 509            }
 510          }
 511          if (isset($block->content) && $block->content) {
 512            // Override default block title if a custom display title is present.
 513            if ($block->title) {
 514              // Check plain here to allow module generated titles to keep any markup.
 515              $block->subject = $block->title == '<none>' ? '' : check_plain($block->title);
 516            }
 517            if (!isset($block->subject)) {
 518              $block->subject = '';
 519            }
 520            $blocks[$block->region]["{$block->module}_{$block->delta}"] = $block;
 521          }
 522        }
 523      }
 524    }
 525    return $blocks[$region];
 526  }
 527  
 528  /**
 529   * Assemble the cache_id to use for a given block.
 530   *
 531   * The cache_id string reflects the viewing context for the current block
 532   * instance, obtained by concatenating the relevant context information
 533   * (user, page, ...) according to the block's cache settings (BLOCK_CACHE_*
 534   * constants). Two block instances can use the same cached content when
 535   * they share the same cache_id.
 536   *
 537   * Theme and language contexts are automatically differenciated.
 538   *
 539   * @param $block
 540   * @return
 541   *   The string used as cache_id for the block.
 542   */
 543  function _block_get_cache_id($block) {
 544    global $theme, $base_root, $user;
 545  
 546    // User 1 being out of the regular 'roles define permissions' schema,
 547    // it brings too many chances of having unwanted output get in the cache
 548    // and later be served to other users. We therefore exclude user 1 from
 549    // block caching.
 550    if (variable_get('block_cache', 0) && $block->cache != BLOCK_NO_CACHE && $user->uid != 1) {
 551      $cid_parts = array();
 552  
 553      // Start with common sub-patterns: block identification, theme, language.
 554      $cid_parts[] = $block->module;
 555      $cid_parts[] = $block->delta;
 556      $cid_parts[] = $theme;
 557      if (module_exists('locale')) {
 558        global $language;
 559        $cid_parts[] = $language->language;
 560      }
 561  
 562      // 'PER_ROLE' and 'PER_USER' are mutually exclusive. 'PER_USER' can be a
 563      // resource drag for sites with many users, so when a module is being
 564      // equivocal, we favor the less expensive 'PER_ROLE' pattern.
 565      if ($block->cache & BLOCK_CACHE_PER_ROLE) {
 566        $cid_parts[] = 'r.'. implode(',', array_keys($user->roles));
 567      }
 568      elseif ($block->cache & BLOCK_CACHE_PER_USER) {
 569        $cid_parts[] = "u.$user->uid";
 570      }
 571  
 572      if ($block->cache & BLOCK_CACHE_PER_PAGE) {
 573        $cid_parts[] = $base_root . request_uri();
 574      }
 575  
 576      return implode(':', $cid_parts);
 577    }
 578  }