drupal/modules/blog/blog.module

<?php
// $Id$

/**
 * @file
 * Enables keeping an easily and regularly updated web page or a blog.
 */

/**
 * Implementation of hook_node_info().
 */
function blog_node_info() {
  return array(
    'blog' => array(
      'name' => t('Blog entry'),
      'module' => 'blog',
      'description' => t('A blog is a regularly updated journal or diary made up of individual posts shown in reversed chronological order. Each member of the site may create and maintain a blog.'),
    )
  );
}

/**
 * Implementation of hook_perm().
 */
function blog_perm() {
  return array('edit own blog');
}

/**
 * Implementation of hook_access().
 */
function blog_access($op, $node) {
  global $user;

  if ($op == 'create') {
    return user_access('edit own blog') && $user->uid;
  }

  if ($op == 'update' || $op == 'delete') {
    if (user_access('edit own blog') && ($user->uid == $node->uid)) {
      return TRUE;
    }
  }
}

/**
 * Implementation of hook_user().
 */
function blog_user($type, &$edit, &$user) {
  if ($type == 'view' && user_access('edit own blog', $user)) {
    $user->content['summary']['blog'] =  array(
      '#type' => 'user_profile_item',
      '#title' => t('Blog'),
      '#value' => l(t('View recent blog entries'), "blog/$user->uid", array('title' => t("Read @username's latest blog entries.", array('@username' => $user->name)))),
      '#attributes' => array('class' => 'blog'),
    );
  }
}

/**
 * Implementation of hook_help().
 */
function blog_help($path, $arg) {
  switch ($path) {
    case 'admin/help#blog':
      $output = '<p>'. t('The blog module allows registered users to maintain an online weblog (commonly known as a blog), often referred to as an online journal or diary. Blogs are made up of individual posts that are time stamped and are typically viewed by date as you would a diary. Blogs often contain links to web pages users have read and/or agree/disagree with.') .'</p>';
      $output .= '<p>'. t('The blog module adds a <em>user blogs</em> navigation link to the site, which takes any visitor to a page that displays the most recent blog entries from all the users on the site. The navigation menu has a <em>create a blog entry</em> link (which takes you to a submission form) and a <em>view personal blog</em> link (which displays your blog entries as other people will see them). The blog module also creates a <em>recent blog posts</em> block that can be enabled.') .'</p>';
      $output .= '<p>'. t('If a user has the ability to post blogs, then the import module (news aggregator) will display a blog-it link next to each news item in its lists. Clicking on this takes the user to the blog submission form, with the title, a link to the item, and a link to the source into the body text already in the text box, ready for the user to add a comment or explanation. This actively encourages people to add blog entries about things they see and hear elsewhere in the website and from your syndicated partner sites.') .'</p>';
      $output .= '<p>'. t('For more information please read the configuration and customization handbook <a href="@blog">Blog page</a>.', array('@blog' => 'http://drupal.org/handbook/modules/blog/')) .'</p>';
      return $output;
  }
}

/**
 * Implementation of hook_form().
 */
function blog_form(&$node) {
  global $nid;
  $iid = isset($_GET['iid']) ? (int)$_GET['iid'] : 0;
  $type = node_get_types('type', $node);


  if (empty($node->body)) {
    /*
    ** If the user clicked a "blog it" link, we load the data from the
    ** database and quote it in the blog:
    */

    if ($nid && $blog = node_load($nid)) {
      $node->body = '<em>'. $blog->body .'</em> ['. l($blog->name, "node/$nid") .']';
    }

    if ($iid && $item = db_fetch_object(db_query('SELECT i.*, f.title as ftitle, f.link as flink FROM {aggregator_item} i, {aggregator_feed} f WHERE i.iid = %d AND i.fid = f.fid', $iid))) {
      $node->title = $item->title;
      // Note: $item->description has been validated on aggregation.
      $node->body = '<a href="'. check_url($item->link) .'">'. check_plain($item->title) .'</a> - <em>'. $item->description .'</em> [<a href="'. check_url($item->flink) .'">'. check_plain($item->ftitle) ."</a>]\n";
    }

  }

  $form['title'] = array('#type' => 'textfield', '#title' => check_plain($type->title_label), '#required' => TRUE, '#default_value' => !empty($node->title) ? $node->title : NULL, '#weight' => -5);
  $form['body_field'] = node_body_field($node, $type->body_label, $type->min_word_count);
  return $form;
}

/**
 * Implementation of hook_view().
 */
function blog_view($node, $teaser = FALSE, $page = FALSE) {
  if ($page) {
    // Breadcrumb navigation
    $breadcrumb[] = array('path' => 'blog', 'title' => t('Blogs'));
    $breadcrumb[] = array('path' => 'blog/'. $node->uid, 'title' => t("@name's blog", array('@name' => $node->name)));
    $breadcrumb[] = array('path' => 'node/'. $node->nid);
    menu_set_location($breadcrumb);
  }
  return node_prepare($node, $teaser);
}

/**
 * Implementation of hook_link().
 */
function blog_link($type, $node = NULL, $teaser = FALSE) {
  $links = array();

  if ($type == 'node' && $node->type == 'blog') {
    if (arg(0) != 'blog' || arg(1) != $node->uid) {
      $links['blog_usernames_blog'] = array(
        'title' => t("@username's blog", array('@username' => $node->name)),
        'href' => "blog/$node->uid",
        'attributes' => array('title' => t("Read @username's latest blog entries.", array('@username' => $node->name)))
      );
    }
  }

  return $links;
}

/**
 * Implementation of hook_menu().
 */
function blog_menu() {
  $items['blog'] = array(
    'title' => 'Blogs',
    'page callback' => 'blog_page_last',
    'access arguments' => array('access content'),
    'type' => MENU_SUGGESTED_ITEM,
    'file' => 'blog.pages.inc',
  );
  $items['blog/%user/view'] = array(
    'title' => 'Blogs',
    'page callback' => 'blog_page_user',
    'access arguments' => array('access content'),
    'type' => MENU_CALLBACK,
    'file' => 'blog.pages.inc',
  );
  $items['blog/%user_current'] = array(
    'title' => 'My blog',
    'page arguments' => array(1),
    'access arguments' => array('edit own blog'),
    'file' => 'blog.pages.inc',
  );
  $items['blog/%user/feed'] = array(
    'title' => 'Blogs',
    'page callback' => 'blog_feed_user',
    'access arguments' => array('access content'),
    'type' => MENU_CALLBACK,
    'file' => 'blog.pages.inc',
  );
  $items['blog/feed'] = array(
    'title' => 'Blogs',
    'page callback' => 'blog_feed_last',
    'access arguments' => array('access content'),
    'type' => MENU_CALLBACK,
    'file' => 'blog.pages.inc',
  );

  return $items;
}

/**
 * Implementation of hook_block().
 *
 * Displays the most recent 10 blog titles.
 */
function blog_block($op = 'list', $delta = 0) {
  global $user;
  if ($op == 'list') {
    $block[0]['info'] = t('Recent blog posts');
    return $block;
  }
  else if ($op == 'view') {
    if (user_access('access content')) {
      $result = db_query_range(db_rewrite_sql("SELECT n.nid, n.title, n.created FROM {node} n WHERE n.type = 'blog' AND n.status = 1 ORDER BY n.created DESC"), 0, 10);
      if ($node_title_list = node_title_list($result)) {
        $block['content'] = $node_title_list;
        $block['content'] .= '<div class="more-link">'. l(t('more'), 'blog', array('title' => t('Read the latest blog entries.'))) .'</div>';
        $block['subject'] = t('Recent blog posts');
        return $block;
      }
    }
  }
}