cms/drupal/includes/mail.inc
changeset 541 e756a8c72c3d
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540:07239de796bb 541:e756a8c72c3d
       
     1 <?php
       
     2 
       
     3 /**
       
     4  * @file
       
     5  * API functions for processing and sending e-mail.
       
     6  */
       
     7 
       
     8 /**
       
     9  * Auto-detect appropriate line endings for e-mails.
       
    10  *
       
    11  * $conf['mail_line_endings'] will override this setting.
       
    12  */
       
    13 define('MAIL_LINE_ENDINGS', isset($_SERVER['WINDIR']) || (isset($_SERVER['SERVER_SOFTWARE']) && strpos($_SERVER['SERVER_SOFTWARE'], 'Win32') !== FALSE) ? "\r\n" : "\n");
       
    14 
       
    15 /**
       
    16  * Composes and optionally sends an e-mail message.
       
    17  *
       
    18  * Sending an e-mail works with defining an e-mail template (subject, text
       
    19  * and possibly e-mail headers) and the replacement values to use in the
       
    20  * appropriate places in the template. Processed e-mail templates are
       
    21  * requested from hook_mail() from the module sending the e-mail. Any module
       
    22  * can modify the composed e-mail message array using hook_mail_alter().
       
    23  * Finally drupal_mail_system()->mail() sends the e-mail, which can
       
    24  * be reused if the exact same composed e-mail is to be sent to multiple
       
    25  * recipients.
       
    26  *
       
    27  * Finding out what language to send the e-mail with needs some consideration.
       
    28  * If you send e-mail to a user, her preferred language should be fine, so
       
    29  * use user_preferred_language(). If you send email based on form values
       
    30  * filled on the page, there are two additional choices if you are not
       
    31  * sending the e-mail to a user on the site. You can either use the language
       
    32  * used to generate the page ($language global variable) or the site default
       
    33  * language. See language_default(). The former is good if sending e-mail to
       
    34  * the person filling the form, the later is good if you send e-mail to an
       
    35  * address previously set up (like contact addresses in a contact form).
       
    36  *
       
    37  * Taking care of always using the proper language is even more important
       
    38  * when sending e-mails in a row to multiple users. Hook_mail() abstracts
       
    39  * whether the mail text comes from an administrator setting or is
       
    40  * static in the source code. It should also deal with common mail tokens,
       
    41  * only receiving $params which are unique to the actual e-mail at hand.
       
    42  *
       
    43  * An example:
       
    44  *
       
    45  * @code
       
    46  *   function example_notify($accounts) {
       
    47  *     foreach ($accounts as $account) {
       
    48  *       $params['account'] = $account;
       
    49  *       // example_mail() will be called based on the first drupal_mail() parameter.
       
    50  *       drupal_mail('example', 'notice', $account->mail, user_preferred_language($account), $params);
       
    51  *     }
       
    52  *   }
       
    53  *
       
    54  *   function example_mail($key, &$message, $params) {
       
    55  *     $data['user'] = $params['account'];
       
    56  *     $options['language'] = $message['language'];
       
    57  *     user_mail_tokens($variables, $data, $options);
       
    58  *     switch($key) {
       
    59  *       case 'notice':
       
    60  *         // If the recipient can receive such notices by instant-message, do
       
    61  *         // not send by email.
       
    62  *         if (example_im_send($key, $message, $params)) {
       
    63  *           $message['send'] = FALSE;
       
    64  *           break;
       
    65  *         }
       
    66  *         $langcode = $message['language']->language;
       
    67  *         $message['subject'] = t('Notification from !site', $variables, array('langcode' => $langcode));
       
    68  *         $message['body'][] = t("Dear !username\n\nThere is new content available on the site.", $variables, array('langcode' => $langcode));
       
    69  *         break;
       
    70  *     }
       
    71  *   }
       
    72  * @endcode
       
    73  *
       
    74  * Another example, which uses drupal_mail() to format a message for sending
       
    75  * later:
       
    76  *
       
    77  * @code
       
    78  *   $params = array('current_conditions' => $data);
       
    79  *   $to = 'user@example.com';
       
    80  *   $message = drupal_mail('example', 'notice', $to, $language, $params, FALSE);
       
    81  *   // Only add to the spool if sending was not canceled.
       
    82  *   if ($message['send']) {
       
    83  *     example_spool_message($message);
       
    84  *   }
       
    85  * @endcode
       
    86  *
       
    87  * @param $module
       
    88  *   A module name to invoke hook_mail() on. The {$module}_mail() hook will be
       
    89  *   called to complete the $message structure which will already contain common
       
    90  *   defaults.
       
    91  * @param $key
       
    92  *   A key to identify the e-mail sent. The final e-mail id for e-mail altering
       
    93  *   will be {$module}_{$key}.
       
    94  * @param $to
       
    95  *   The e-mail address or addresses where the message will be sent to. The
       
    96  *   formatting of this string will be validated with the
       
    97  *   @link http://php.net/manual/filter.filters.validate.php PHP e-mail validation filter. @endlink
       
    98  *   Some examples are:
       
    99  *   - user@example.com
       
   100  *   - user@example.com, anotheruser@example.com
       
   101  *   - User <user@example.com>
       
   102  *   - User <user@example.com>, Another User <anotheruser@example.com>
       
   103  * @param $language
       
   104  *   Language object to use to compose the e-mail.
       
   105  * @param $params
       
   106  *   Optional parameters to build the e-mail.
       
   107  * @param $from
       
   108  *   Sets From to this value, if given.
       
   109  * @param $send
       
   110  *   If TRUE, drupal_mail() will call drupal_mail_system()->mail() to deliver
       
   111  *   the message, and store the result in $message['result']. Modules
       
   112  *   implementing hook_mail_alter() may cancel sending by setting
       
   113  *   $message['send'] to FALSE.
       
   114  *
       
   115  * @return
       
   116  *   The $message array structure containing all details of the
       
   117  *   message. If already sent ($send = TRUE), then the 'result' element
       
   118  *   will contain the success indicator of the e-mail, failure being already
       
   119  *   written to the watchdog. (Success means nothing more than the message being
       
   120  *   accepted at php-level, which still doesn't guarantee it to be delivered.)
       
   121  */
       
   122 function drupal_mail($module, $key, $to, $language, $params = array(), $from = NULL, $send = TRUE) {
       
   123   $default_from = variable_get('site_mail', ini_get('sendmail_from'));
       
   124 
       
   125   // Bundle up the variables into a structured array for altering.
       
   126   $message = array(
       
   127     'id'       => $module . '_' . $key,
       
   128     'module'   => $module,
       
   129     'key'      => $key,
       
   130     'to'       => $to,
       
   131     'from'     => isset($from) ? $from : $default_from,
       
   132     'language' => $language,
       
   133     'params'   => $params,
       
   134     'send'     => TRUE,
       
   135     'subject'  => '',
       
   136     'body'     => array()
       
   137   );
       
   138 
       
   139   // Build the default headers
       
   140   $headers = array(
       
   141     'MIME-Version'              => '1.0',
       
   142     'Content-Type'              => 'text/plain; charset=UTF-8; format=flowed; delsp=yes',
       
   143     'Content-Transfer-Encoding' => '8Bit',
       
   144     'X-Mailer'                  => 'Drupal'
       
   145   );
       
   146   if ($default_from) {
       
   147     // To prevent e-mail from looking like spam, the addresses in the Sender and
       
   148     // Return-Path headers should have a domain authorized to use the originating
       
   149     // SMTP server.
       
   150     $headers['From'] = $headers['Sender'] = $headers['Return-Path'] = $default_from;
       
   151   }
       
   152   if ($from) {
       
   153     $headers['From'] = $from;
       
   154   }
       
   155   $message['headers'] = $headers;
       
   156 
       
   157   // Build the e-mail (get subject and body, allow additional headers) by
       
   158   // invoking hook_mail() on this module. We cannot use module_invoke() as
       
   159   // we need to have $message by reference in hook_mail().
       
   160   if (function_exists($function = $module . '_mail')) {
       
   161     $function($key, $message, $params);
       
   162   }
       
   163 
       
   164   // Invoke hook_mail_alter() to allow all modules to alter the resulting e-mail.
       
   165   drupal_alter('mail', $message);
       
   166 
       
   167   // Retrieve the responsible implementation for this message.
       
   168   $system = drupal_mail_system($module, $key);
       
   169 
       
   170   // Format the message body.
       
   171   $message = $system->format($message);
       
   172 
       
   173   // Optionally send e-mail.
       
   174   if ($send) {
       
   175     // The original caller requested sending. Sending was canceled by one or
       
   176     // more hook_mail_alter() implementations. We set 'result' to NULL, because
       
   177     // FALSE indicates an error in sending.
       
   178     if (empty($message['send'])) {
       
   179       $message['result'] = NULL;
       
   180     }
       
   181     // Sending was originally requested and was not canceled.
       
   182     else {
       
   183       $message['result'] = $system->mail($message);
       
   184       // Log errors.
       
   185       if (!$message['result']) {
       
   186         watchdog('mail', 'Error sending e-mail (from %from to %to).', array('%from' => $message['from'], '%to' => $message['to']), WATCHDOG_ERROR);
       
   187         drupal_set_message(t('Unable to send e-mail. Contact the site administrator if the problem persists.'), 'error');
       
   188       }
       
   189     }
       
   190   }
       
   191 
       
   192   return $message;
       
   193 }
       
   194 
       
   195 /**
       
   196  * Returns an object that implements the MailSystemInterface interface.
       
   197  *
       
   198  * Allows for one or more custom mail backends to format and send mail messages
       
   199  * composed using drupal_mail().
       
   200  *
       
   201  * An implementation needs to implement the following methods:
       
   202  * - format: Allows to preprocess, format, and postprocess a mail
       
   203  *   message before it is passed to the sending system. By default, all messages
       
   204  *   may contain HTML and are converted to plain-text by the DefaultMailSystem
       
   205  *   implementation. For example, an alternative implementation could override
       
   206  *   the default implementation and additionally sanitize the HTML for usage in
       
   207  *   a MIME-encoded e-mail, but still invoking the DefaultMailSystem
       
   208  *   implementation to generate an alternate plain-text version for sending.
       
   209  * - mail: Sends a message through a custom mail sending engine.
       
   210  *   By default, all messages are sent via PHP's mail() function by the
       
   211  *   DefaultMailSystem implementation.
       
   212  *
       
   213  * The selection of a particular implementation is controlled via the variable
       
   214  * 'mail_system', which is a keyed array.  The default implementation
       
   215  * is the class whose name is the value of 'default-system' key. A more specific
       
   216  * match first to key and then to module will be used in preference to the
       
   217  * default. To specify a different class for all mail sent by one module, set
       
   218  * the class name as the value for the key corresponding to the module name. To
       
   219  * specify a class for a particular message sent by one module, set the class
       
   220  * name as the value for the array key that is the message id, which is
       
   221  * "${module}_${key}".
       
   222  *
       
   223  * For example to debug all mail sent by the user module by logging it to a
       
   224  * file, you might set the variable as something like:
       
   225  *
       
   226  * @code
       
   227  * array(
       
   228  *   'default-system' => 'DefaultMailSystem',
       
   229  *   'user' => 'DevelMailLog',
       
   230  * );
       
   231  * @endcode
       
   232  *
       
   233  * Finally, a different system can be specified for a specific e-mail ID (see
       
   234  * the $key param), such as one of the keys used by the contact module:
       
   235  *
       
   236  * @code
       
   237  * array(
       
   238  *   'default-system' => 'DefaultMailSystem',
       
   239  *   'user' => 'DevelMailLog',
       
   240  *   'contact_page_autoreply' => 'DrupalDevNullMailSend',
       
   241  * );
       
   242  * @endcode
       
   243  *
       
   244  * Other possible uses for system include a mail-sending class that actually
       
   245  * sends (or duplicates) each message to SMS, Twitter, instant message, etc, or
       
   246  * a class that queues up a large number of messages for more efficient bulk
       
   247  * sending or for sending via a remote gateway so as to reduce the load
       
   248  * on the local server.
       
   249  *
       
   250  * @param $module
       
   251  *   The module name which was used by drupal_mail() to invoke hook_mail().
       
   252  * @param $key
       
   253  *   A key to identify the e-mail sent. The final e-mail ID for the e-mail
       
   254  *   alter hook in drupal_mail() would have been {$module}_{$key}.
       
   255  *
       
   256  * @return MailSystemInterface
       
   257  */
       
   258 function drupal_mail_system($module, $key) {
       
   259   $instances = &drupal_static(__FUNCTION__, array());
       
   260 
       
   261   $id = $module . '_' . $key;
       
   262 
       
   263   $configuration = variable_get('mail_system', array('default-system' => 'DefaultMailSystem'));
       
   264 
       
   265   // Look for overrides for the default class, starting from the most specific
       
   266   // id, and falling back to the module name.
       
   267   if (isset($configuration[$id])) {
       
   268     $class = $configuration[$id];
       
   269   }
       
   270   elseif (isset($configuration[$module])) {
       
   271     $class = $configuration[$module];
       
   272   }
       
   273   else {
       
   274     $class = $configuration['default-system'];
       
   275   }
       
   276 
       
   277   if (empty($instances[$class])) {
       
   278     $interfaces = class_implements($class);
       
   279     if (isset($interfaces['MailSystemInterface'])) {
       
   280       $instances[$class] = new $class();
       
   281     }
       
   282     else {
       
   283       throw new Exception(t('Class %class does not implement interface %interface', array('%class' => $class, '%interface' => 'MailSystemInterface')));
       
   284     }
       
   285   }
       
   286   return $instances[$class];
       
   287 }
       
   288 
       
   289 /**
       
   290  * An interface for pluggable mail back-ends.
       
   291  */
       
   292 interface MailSystemInterface {
       
   293   /**
       
   294    * Format a message composed by drupal_mail() prior sending.
       
   295    *
       
   296    * @param $message
       
   297    *   A message array, as described in hook_mail_alter().
       
   298    *
       
   299    * @return
       
   300    *   The formatted $message.
       
   301    */
       
   302    public function format(array $message);
       
   303 
       
   304   /**
       
   305    * Send a message composed by drupal_mail().
       
   306    *
       
   307    * @param $message
       
   308    *   Message array with at least the following elements:
       
   309    *   - id: A unique identifier of the e-mail type. Examples: 'contact_user_copy',
       
   310    *     'user_password_reset'.
       
   311    *   - to: The mail address or addresses where the message will be sent to.
       
   312    *     The formatting of this string will be validated with the
       
   313    *     @link http://php.net/manual/filter.filters.validate.php PHP e-mail validation filter. @endlink
       
   314    *     Some examples are:
       
   315    *     - user@example.com
       
   316    *     - user@example.com, anotheruser@example.com
       
   317    *     - User <user@example.com>
       
   318    *     - User <user@example.com>, Another User <anotheruser@example.com>
       
   319    *   - subject: Subject of the e-mail to be sent. This must not contain any
       
   320    *     newline characters, or the mail may not be sent properly.
       
   321    *   - body: Message to be sent. Accepts both CRLF and LF line-endings.
       
   322    *     E-mail bodies must be wrapped. You can use drupal_wrap_mail() for
       
   323    *     smart plain text wrapping.
       
   324    *   - headers: Associative array containing all additional mail headers not
       
   325    *     defined by one of the other parameters.  PHP's mail() looks for Cc and
       
   326    *     Bcc headers and sends the mail to addresses in these headers too.
       
   327    *
       
   328    * @return
       
   329    *   TRUE if the mail was successfully accepted for delivery, otherwise FALSE.
       
   330    */
       
   331    public function mail(array $message);
       
   332 }
       
   333 
       
   334 /**
       
   335  * Performs format=flowed soft wrapping for mail (RFC 3676).
       
   336  *
       
   337  * We use delsp=yes wrapping, but only break non-spaced languages when
       
   338  * absolutely necessary to avoid compatibility issues.
       
   339  *
       
   340  * We deliberately use LF rather than CRLF, see drupal_mail().
       
   341  *
       
   342  * @param string $text
       
   343  *   The plain text to process.
       
   344  * @param string $indent (optional)
       
   345  *   A string to indent the text with. Only '>' characters are repeated on
       
   346  *   subsequent wrapped lines. Others are replaced by spaces.
       
   347  *
       
   348  * @return string
       
   349  *   The content of the email as a string with formatting applied.
       
   350  */
       
   351 function drupal_wrap_mail($text, $indent = '') {
       
   352   // Convert CRLF into LF.
       
   353   $text = str_replace("\r", '', $text);
       
   354   // See if soft-wrapping is allowed.
       
   355   $clean_indent = _drupal_html_to_text_clean($indent);
       
   356   $soft = strpos($clean_indent, ' ') === FALSE;
       
   357   // Check if the string has line breaks.
       
   358   if (strpos($text, "\n") !== FALSE) {
       
   359     // Remove trailing spaces to make existing breaks hard, but leave signature
       
   360     // marker untouched (RFC 3676, Section 4.3).
       
   361     $text = preg_replace('/(?(?<!^--) +\n|  +\n)/m', "\n", $text);
       
   362     // Wrap each line at the needed width.
       
   363     $lines = explode("\n", $text);
       
   364     array_walk($lines, '_drupal_wrap_mail_line', array('soft' => $soft, 'length' => strlen($indent)));
       
   365     $text = implode("\n", $lines);
       
   366   }
       
   367   else {
       
   368     // Wrap this line.
       
   369     _drupal_wrap_mail_line($text, 0, array('soft' => $soft, 'length' => strlen($indent)));
       
   370   }
       
   371   // Empty lines with nothing but spaces.
       
   372   $text = preg_replace('/^ +\n/m', "\n", $text);
       
   373   // Space-stuff special lines.
       
   374   $text = preg_replace('/^(>| |From)/m', ' $1', $text);
       
   375   // Apply indentation. We only include non-'>' indentation on the first line.
       
   376   $text = $indent . substr(preg_replace('/^/m', $clean_indent, $text), strlen($indent));
       
   377 
       
   378   return $text;
       
   379 }
       
   380 
       
   381 /**
       
   382  * Transforms an HTML string into plain text, preserving its structure.
       
   383  *
       
   384  * The output will be suitable for use as 'format=flowed; delsp=yes' text
       
   385  * (RFC 3676) and can be passed directly to drupal_mail() for sending.
       
   386  *
       
   387  * We deliberately use LF rather than CRLF, see drupal_mail().
       
   388  *
       
   389  * This function provides suitable alternatives for the following tags:
       
   390  * <a> <em> <i> <strong> <b> <br> <p> <blockquote> <ul> <ol> <li> <dl> <dt>
       
   391  * <dd> <h1> <h2> <h3> <h4> <h5> <h6> <hr>
       
   392  *
       
   393  * @param $string
       
   394  *   The string to be transformed.
       
   395  * @param $allowed_tags (optional)
       
   396  *   If supplied, a list of tags that will be transformed. If omitted, all
       
   397  *   all supported tags are transformed.
       
   398  *
       
   399  * @return
       
   400  *   The transformed string.
       
   401  */
       
   402 function drupal_html_to_text($string, $allowed_tags = NULL) {
       
   403   // Cache list of supported tags.
       
   404   static $supported_tags;
       
   405   if (empty($supported_tags)) {
       
   406     $supported_tags = array('a', 'em', 'i', 'strong', 'b', 'br', 'p', 'blockquote', 'ul', 'ol', 'li', 'dl', 'dt', 'dd', 'h1', 'h2', 'h3', 'h4', 'h5', 'h6', 'hr');
       
   407   }
       
   408 
       
   409   // Make sure only supported tags are kept.
       
   410   $allowed_tags = isset($allowed_tags) ? array_intersect($supported_tags, $allowed_tags) : $supported_tags;
       
   411 
       
   412   // Make sure tags, entities and attributes are well-formed and properly nested.
       
   413   $string = _filter_htmlcorrector(filter_xss($string, $allowed_tags));
       
   414 
       
   415   // Apply inline styles.
       
   416   $string = preg_replace('!</?(em|i)((?> +)[^>]*)?>!i', '/', $string);
       
   417   $string = preg_replace('!</?(strong|b)((?> +)[^>]*)?>!i', '*', $string);
       
   418 
       
   419   // Replace inline <a> tags with the text of link and a footnote.
       
   420   // 'See <a href="http://drupal.org">the Drupal site</a>' becomes
       
   421   // 'See the Drupal site [1]' with the URL included as a footnote.
       
   422   _drupal_html_to_mail_urls(NULL, TRUE);
       
   423   $pattern = '@(<a[^>]+?href="([^"]*)"[^>]*?>(.+?)</a>)@i';
       
   424   $string = preg_replace_callback($pattern, '_drupal_html_to_mail_urls', $string);
       
   425   $urls = _drupal_html_to_mail_urls();
       
   426   $footnotes = '';
       
   427   if (count($urls)) {
       
   428     $footnotes .= "\n";
       
   429     for ($i = 0, $max = count($urls); $i < $max; $i++) {
       
   430       $footnotes .= '[' . ($i + 1) . '] ' . $urls[$i] . "\n";
       
   431     }
       
   432   }
       
   433 
       
   434   // Split tags from text.
       
   435   $split = preg_split('/<([^>]+?)>/', $string, -1, PREG_SPLIT_DELIM_CAPTURE);
       
   436   // Note: PHP ensures the array consists of alternating delimiters and literals
       
   437   // and begins and ends with a literal (inserting $null as required).
       
   438 
       
   439   $tag = FALSE; // Odd/even counter (tag or no tag)
       
   440   $casing = NULL; // Case conversion function
       
   441   $output = '';
       
   442   $indent = array(); // All current indentation string chunks
       
   443   $lists = array(); // Array of counters for opened lists
       
   444   foreach ($split as $value) {
       
   445     $chunk = NULL; // Holds a string ready to be formatted and output.
       
   446 
       
   447     // Process HTML tags (but don't output any literally).
       
   448     if ($tag) {
       
   449       list($tagname) = explode(' ', strtolower($value), 2);
       
   450       switch ($tagname) {
       
   451         // List counters
       
   452         case 'ul':
       
   453           array_unshift($lists, '*');
       
   454           break;
       
   455         case 'ol':
       
   456           array_unshift($lists, 1);
       
   457           break;
       
   458         case '/ul':
       
   459         case '/ol':
       
   460           array_shift($lists);
       
   461           $chunk = ''; // Ensure blank new-line.
       
   462           break;
       
   463 
       
   464         // Quotation/list markers, non-fancy headers
       
   465         case 'blockquote':
       
   466           // Format=flowed indentation cannot be mixed with lists.
       
   467           $indent[] = count($lists) ? ' "' : '>';
       
   468           break;
       
   469         case 'li':
       
   470           $indent[] = isset($lists[0]) && is_numeric($lists[0]) ? ' ' . $lists[0]++ . ') ' : ' * ';
       
   471           break;
       
   472         case 'dd':
       
   473           $indent[] = '    ';
       
   474           break;
       
   475         case 'h3':
       
   476           $indent[] = '.... ';
       
   477           break;
       
   478         case 'h4':
       
   479           $indent[] = '.. ';
       
   480           break;
       
   481         case '/blockquote':
       
   482           if (count($lists)) {
       
   483             // Append closing quote for inline quotes (immediately).
       
   484             $output = rtrim($output, "> \n") . "\"\n";
       
   485             $chunk = ''; // Ensure blank new-line.
       
   486           }
       
   487           // Fall-through
       
   488         case '/li':
       
   489         case '/dd':
       
   490           array_pop($indent);
       
   491           break;
       
   492         case '/h3':
       
   493         case '/h4':
       
   494           array_pop($indent);
       
   495         case '/h5':
       
   496         case '/h6':
       
   497           $chunk = ''; // Ensure blank new-line.
       
   498           break;
       
   499 
       
   500         // Fancy headers
       
   501         case 'h1':
       
   502           $indent[] = '======== ';
       
   503           $casing = 'drupal_strtoupper';
       
   504           break;
       
   505         case 'h2':
       
   506           $indent[] = '-------- ';
       
   507           $casing = 'drupal_strtoupper';
       
   508           break;
       
   509         case '/h1':
       
   510         case '/h2':
       
   511           $casing = NULL;
       
   512           // Pad the line with dashes.
       
   513           $output = _drupal_html_to_text_pad($output, ($tagname == '/h1') ? '=' : '-', ' ');
       
   514           array_pop($indent);
       
   515           $chunk = ''; // Ensure blank new-line.
       
   516           break;
       
   517 
       
   518         // Horizontal rulers
       
   519         case 'hr':
       
   520           // Insert immediately.
       
   521           $output .= drupal_wrap_mail('', implode('', $indent)) . "\n";
       
   522           $output = _drupal_html_to_text_pad($output, '-');
       
   523           break;
       
   524 
       
   525         // Paragraphs and definition lists
       
   526         case '/p':
       
   527         case '/dl':
       
   528           $chunk = ''; // Ensure blank new-line.
       
   529           break;
       
   530       }
       
   531     }
       
   532     // Process blocks of text.
       
   533     else {
       
   534       // Convert inline HTML text to plain text; not removing line-breaks or
       
   535       // white-space, since that breaks newlines when sanitizing plain-text.
       
   536       $value = trim(decode_entities($value));
       
   537       if (drupal_strlen($value)) {
       
   538         $chunk = $value;
       
   539       }
       
   540     }
       
   541 
       
   542     // See if there is something waiting to be output.
       
   543     if (isset($chunk)) {
       
   544       // Apply any necessary case conversion.
       
   545       if (isset($casing)) {
       
   546         $chunk = $casing($chunk);
       
   547       }
       
   548       // Format it and apply the current indentation.
       
   549       $output .= drupal_wrap_mail($chunk, implode('', $indent)) . MAIL_LINE_ENDINGS;
       
   550       // Remove non-quotation markers from indentation.
       
   551       $indent = array_map('_drupal_html_to_text_clean', $indent);
       
   552     }
       
   553 
       
   554     $tag = !$tag;
       
   555   }
       
   556 
       
   557   return $output . $footnotes;
       
   558 }
       
   559 
       
   560 /**
       
   561  * Wraps words on a single line.
       
   562  *
       
   563  * Callback for array_walk() winthin drupal_wrap_mail().
       
   564  */
       
   565 function _drupal_wrap_mail_line(&$line, $key, $values) {
       
   566   // Use soft-breaks only for purely quoted or unindented text.
       
   567   $line = wordwrap($line, 77 - $values['length'], $values['soft'] ? " \n" : "\n");
       
   568   // Break really long words at the maximum width allowed.
       
   569   $line = wordwrap($line, 996 - $values['length'], $values['soft'] ? " \n" : "\n", TRUE);
       
   570 }
       
   571 
       
   572 /**
       
   573  * Keeps track of URLs and replaces them with placeholder tokens.
       
   574  *
       
   575  * Callback for preg_replace_callback() within drupal_html_to_text().
       
   576  */
       
   577 function _drupal_html_to_mail_urls($match = NULL, $reset = FALSE) {
       
   578   global $base_url, $base_path;
       
   579   static $urls = array(), $regexp;
       
   580 
       
   581   if ($reset) {
       
   582     // Reset internal URL list.
       
   583     $urls = array();
       
   584   }
       
   585   else {
       
   586     if (empty($regexp)) {
       
   587       $regexp = '@^' . preg_quote($base_path, '@') . '@';
       
   588     }
       
   589     if ($match) {
       
   590       list(, , $url, $label) = $match;
       
   591       // Ensure all URLs are absolute.
       
   592       $urls[] = strpos($url, '://') ? $url : preg_replace($regexp, $base_url . '/', $url);
       
   593       return $label . ' [' . count($urls) . ']';
       
   594     }
       
   595   }
       
   596   return $urls;
       
   597 }
       
   598 
       
   599 /**
       
   600  * Replaces non-quotation markers from a given piece of indentation with spaces.
       
   601  *
       
   602  * Callback for array_map() within drupal_html_to_text().
       
   603  */
       
   604 function _drupal_html_to_text_clean($indent) {
       
   605   return preg_replace('/[^>]/', ' ', $indent);
       
   606 }
       
   607 
       
   608 /**
       
   609  * Pads the last line with the given character.
       
   610  *
       
   611  * @see drupal_html_to_text()
       
   612  */
       
   613 function _drupal_html_to_text_pad($text, $pad, $prefix = '') {
       
   614   // Remove last line break.
       
   615   $text = substr($text, 0, -1);
       
   616   // Calculate needed padding space and add it.
       
   617   if (($p = strrpos($text, "\n")) === FALSE) {
       
   618     $p = -1;
       
   619   }
       
   620   $n = max(0, 79 - (strlen($text) - $p) - strlen($prefix));
       
   621   // Add prefix and padding, and restore linebreak.
       
   622   return $text . $prefix . str_repeat($pad, $n) . "\n";
       
   623 }