function _block_render_blocks

Render the content and subject for a set of blocks.

Parameters

$region_blocks: An array of block objects such as returned for one region by _block_load_blocks().

Return value

An array of visible blocks as expected by drupal_render().

File

drupal/modules/block/block.module, line 859

Controls the visual building blocks a page is constructed with.

Code

function _block_render_blocks($region_blocks) {
  $cacheable = TRUE;

  // We preserve the submission of forms in blocks, by fetching from cache only
  // if the request method is 'GET' (or 'HEAD').
  if ($_SERVER['REQUEST_METHOD'] != 'GET' && $_SERVER['REQUEST_METHOD'] != 'HEAD') {
    $cacheable = FALSE;
  }
  elseif (!variable_get('block_cache_bypass_node_grants', FALSE) && count(module_implements('node_grants'))) {
    $cacheable = FALSE;
  }

  // Proceed to loop over all blocks in order to compute their respective cache
  // identifiers; this allows us to do one single cache_get_multiple() call
  // instead of doing one cache_get() call per block.
  $cached_blocks = array();
  $cids = array();
  if ($cacheable) {
    foreach ($region_blocks as $key => $block) {
      if (!isset($block->content)) {
        if ($cid = _block_get_cache_id($block)) {
          $cids[$key] = $cid;
        }
      }
    }
    if ($cids) {

      // We cannot pass $cids in directly because cache_get_multiple() will
      // modify it, and we need to use it later on in this function.
      $cid_values = array_values($cids);
      $cached_blocks = cache_get_multiple($cid_values, 'cache_block');
    }
  }
  foreach ($region_blocks as $key => $block) {

    // Render the block content if it has not been created already.
    if (!isset($block->content)) {

      // Erase the block from the static array - we'll put it back if it has
      // content.
      unset($region_blocks[$key]);
      $cid = empty($cids[$key]) ? NULL : $cids[$key];

      // Try fetching the block from the previously loaded cache entries.
      if (isset($cached_blocks[$cid])) {
        $array = $cached_blocks[$cid]->data;
      }
      else {
        $array = module_invoke($block->module, 'block_view', $block->delta);

        // Valid PHP function names cannot contain hyphens.
        $delta = str_replace('-', '_', $block->delta);

        // Allow modules to modify the block before it is viewed, via either
        // hook_block_view_alter() or hook_block_view_MODULE_DELTA_alter().
        drupal_alter(array(
          'block_view',
          "block_view_{$block->module}_{$delta}",
        ), $array, $block);
        if (isset($cid)) {
          cache_set($cid, $array, 'cache_block', CACHE_TEMPORARY);
        }
      }
      if (isset($array) && is_array($array)) {
        foreach ($array as $k => $v) {
          $block->{$k} = $v;
        }
      }
      if (isset($block->content) && $block->content) {

        // Normalize to the drupal_render() structure.
        if (is_string($block->content)) {
          $block->content = array(
            '#markup' => $block->content,
          );
        }

        // Override default block title if a custom display title is present.
        if ($block->title) {

          // Check plain here to allow module generated titles to keep any
          // markup.
          $block->subject = $block->title == '<none>' ? '' : check_plain($block->title);
        }
        if (!isset($block->subject)) {
          $block->subject = '';
        }
        $region_blocks["{$block->module}_{$block->delta}"] = $block;
      }
    }
  }
  return $region_blocks;
}