tags that wrap ![]()
tags.
$pattern = "#((]*\s+)href\s*=\s*[\"|'])($url_prefix_regex)([^\"|^'|^\?]*)()(\?[^\"|^']*)?";
$pattern .= "("; // Capture everything after the path.
$pattern .= "([\"|'][^>]*)>"; // End of opening tag.
$pattern .= "((]*\s+)src\s*=\s*[\"|'])([^\"|^'|^\?]*)()(\?[^\"|^']*)?([\"|'])"; // Wrapped ![]()
tag.
$pattern .= ")#i";
_cdn_html_alter_file_url($html, $pattern, 0, 4, 6, 1, 7, 11);
// Image file URLs in ![]()
tags.
$pattern = "#((]*\s+)src\s*=\s*[\"|'])($url_prefix_regex)([^\"|^'|^\?]*)()(\?[^\"|^']*)?([\"|'])#i";
_cdn_html_alter_file_url($html, $pattern, 0, 4, 6, 1, 7);
}
/**
* Alter file download URLs.
*/
function cdn_html_alter_anchor_urls(&$html) {
$url_prefix_regex = _cdn_generate_url_prefix_regex();
$pattern = "#((]*\s+)href\s*=\s*[\"|'])($url_prefix_regex)([^\"|^'|^\?]*)()(\?[^\"|^']*)?([\"|'])#i";
_cdn_html_alter_file_url($html, $pattern, 0, 4, 6, 1, 7, FALSE, TRUE);
}
/**
* Generate the URL prefix regular expression, that supports all possible
* types of file URLs: root-relative, protocol-relative and absolute URLs.
*/
function _cdn_generate_url_prefix_regex() {
global $base_url;
static $url_prefix_regex;
if (!isset($url_prefix_regex)) {
$url_prefixes = array(
preg_quote(base_path()) . '(?!/)', // Root-relative URL.
// Note: root-relative URL that isn't a protocol-relative URL. The
// negative lookahead for a trailing slash is relaly only necessary
// when this site is installed in the document root (i.e. when the base
// path equals "/"), because this would otherwise match *all* protocol-
// relative URLs, also those that already point to the CDN.
preg_quote('//' . $_SERVER['HTTP_HOST'] . base_path()), // Protocol-relative URL.
preg_quote($base_url . '/'), // Absolute URL.
);
$regexes = array();
$farfuture = preg_quote('cdn/farfuture/');
foreach ($url_prefixes as $url_prefix) {
$regexes[] = $url_prefix . '(?!' . $farfuture . ')';
}
// The URL prefix regex that will match all URLs to the current site,
// except for those that already point to Far Future expiration URLs.
$url_prefix_regex = implode('|', $regexes);
}
return $url_prefix_regex;
}
/**
* Alter the file URLs in a piece of HTML given a regexp pattern and some
* additional parameters.
*
* @param &$html
* The HTML in which file URLs will be altered.
* @param $pattern
* A regular expression pattern to apply to the subject.
* @param $search_index
* The index of the search string in the array of regexp matches.
* @param $path_index
* The index of the file path in the array of regexp matches.
* @param $querystring_index
* The index of (an optional) query string in the array of regexp matches.
* @param $prefix
* $search_index will be replaced by $prefix, plus the altered file URL,
* plus the @suffix. If numeric, then it is assumed to be the index of the
* prefix in the array of regexp matches.
* @param $suffix
* See $prefix.
* @param $comparison_index
* The index of a comparison path whose file extension should match the file
* extension of the path located at $path_index.
* @param $require_extension_match
* Whether the extension must match a specific extension mapped to a CDN
* server. This is used when it is undesirable for a path matching only the
* '*' matcher in the CDN mapping, such as when converting miscellaneous
* anchor links.
*/
function _cdn_html_alter_file_url(&$html, $pattern, $search_index, $path_index, $querystring_index, $prefix, $suffix, $comparison_index = FALSE, $require_extension_match = FALSE) {
$mapping = &drupal_static(__FUNCTION__ . '$mapping');
// Find a match against the given pattern.
preg_match_all($pattern, $html, $matches);
// Generate replacements to alter file URLs.
$searches = array();
$replacements = array();
for ($i = 0; $i < count($matches[0]); $i++) {
$search = $matches[$search_index][$i];
$path = $matches[$path_index][$i];
$prefix_string = (is_numeric($prefix)) ? $matches[$prefix][$i] : $prefix;
$suffix_string = (is_numeric($suffix)) ? $matches[$suffix][$i] : $suffix;
// Compare the filename in the path with that of another index. The file
// URL only is rewritten if it matches.
if ($comparison_index) {
$comparison = $matches[$comparison_index][$i];
// Calculate length of extension.
$path_ext_pos = strrpos($path, '.');
$ext_length = -1 * (strlen($path) - $path_ext_pos);
if (substr($path, $ext_length) !== substr($comparison, $ext_length)) {
continue;
}
}
if ($require_extension_match) {
if (!isset($mapping)) {
cdn_load_include('basic');
$mapping = _cdn_basic_parse_raw_mapping(cdn_basic_get_mapping());
}
$file_extension = drupal_strtolower(pathinfo($path, PATHINFO_EXTENSION));
if (!array_key_exists($file_extension, $mapping)) {
continue;
}
}
// Store the current path as the old path, then let cdn_file_url_alter()
// do its magic by invoking all file_url_alter hooks. When the path hasn't
// changed and is not already root-relative or protocol-relative, then
// generate a file URL as Drupal core would: prepend the base path.
$old_path = $path;
drupal_alter('file_url', $path);
if ($path == $old_path && drupal_substr($path, 0, 1) != '/' && drupal_substr($path, 0, 2) != '//') {
$path = base_path() . $path;
}
$searches[] = $search;
$replacements[] = $prefix_string . $path . $matches[$querystring_index][$i] . $suffix_string;
}
// Apply the generated replacements ton the subject.
$html = str_replace($searches, $replacements, $html);
}