+ * // [footag foo="bar"]
+ * function footag_func($atts) {
+ * return "foo = {$atts[foo]}";
+ * }
+ * add_shortcode('footag', 'footag_func');
+ *
+ *
+ * Example with nice attribute defaults:
+ *
+ *
+ * // [bartag foo="bar"]
+ * function bartag_func($atts) {
+ * extract(shortcode_atts(array(
+ * 'foo' => 'no foo',
+ * 'baz' => 'default baz',
+ * ), $atts));
+ *
+ * return "foo = {$foo}";
+ * }
+ * add_shortcode('bartag', 'bartag_func');
+ *
+ *
+ * Example with enclosed content:
+ *
+ *
+ * // [baztag]content[/baztag]
+ * function baztag_func($atts, $content='') {
+ * return "content = $content";
+ * }
+ * add_shortcode('baztag', 'baztag_func');
+ *
+ *
+ * @since 2.5
+ * @uses $shortcode_tags
+ *
+ * @param string $tag Shortcode tag to be searched in post content.
+ * @param callable $func Hook to run when shortcode is found.
+ */
+function add_shortcode($tag, $func) {
+ global $shortcode_tags;
+
+ if ( is_callable($func) )
+ $shortcode_tags[$tag] = $func;
+}
+
+/**
+ * Search content for shortcodes and filter shortcodes through their hooks.
+ *
+ * If there are no shortcode tags defined, then the content will be returned
+ * without any filtering. This might cause issues when plugins are disabled but
+ * the shortcode will still show up in the post or content.
+ *
+ * @since 2.5
+ * @uses $shortcode_tags
+ * @uses get_shortcode_regex() Gets the search pattern for searching shortcodes.
+ *
+ * @param string $content Content to search for shortcodes
+ * @return string Content with shortcodes filtered out.
+ */
+function do_shortcode($content) {
+ global $shortcode_tags;
+
+ if (empty($shortcode_tags) || !is_array($shortcode_tags))
+ return $content;
+
+ $pattern = get_shortcode_regex();
+ return preg_replace_callback('/'.$pattern.'/s', 'do_shortcode_tag', $content);
+}
+
+/**
+ * Retrieve the shortcode regular expression for searching.
+ *
+ * The regular expression combines the shortcode tags in the regular expression
+ * in a regex class.
+ *
+ * The regular expresion contains 6 different sub matches to help with parsing.
+ *
+ * 1/6 - An extra [ or ] to allow for escaping shortcodes with double [[]]
+ * 2 - The shortcode name
+ * 3 - The shortcode argument list
+ * 4 - The self closing /
+ * 5 - The content of a shortcode when it wraps some content.
+ *
+ * @since 2.5
+ * @uses $shortcode_tags
+ *
+ * @return string The shortcode search regular expression
+ */
+function get_shortcode_regex() {
+ global $shortcode_tags;
+ $tagnames = array_keys($shortcode_tags);
+ $tagregexp = join( '|', array_map('preg_quote', $tagnames) );
+
+ // WARNING! Do not change this regex without changing do_shortcode_tag() and strip_shortcodes()
+ return '(.?)\[('.$tagregexp.')\b(.*?)(?:(\/))?\](?:(.+?)\[\/\2\])?(.?)';
+}
+
+/**
+ * Regular Expression callable for do_shortcode() for calling shortcode hook.
+ * @see get_shortcode_regex for details of the match array contents.
+ *
+ * @since 2.5
+ * @access private
+ * @uses $shortcode_tags
+ *
+ * @param array $m Regular expression match array
+ * @return mixed False on failure.
+ */
+function do_shortcode_tag( $m ) {
+ global $shortcode_tags;
+
+ // allow [[foo]] syntax for escaping a tag
+ if ( $m[1] == '[' && $m[6] == ']' ) {
+ return substr($m[0], 1, -1);
+ }
+
+ $tag = $m[2];
+ $attr = shortcode_parse_atts( $m[3] );
+
+ if ( isset( $m[5] ) ) {
+ // enclosing tag - extra parameter
+ return $m[1] . call_user_func( $shortcode_tags[$tag], $attr, $m[5], $tag ) . $m[6];
+ } else {
+ // self-closing tag
+ return $m[1] . call_user_func( $shortcode_tags[$tag], $attr, NULL, $tag ) . $m[6];
+ }
+}
+
+/**
+ * Retrieve all attributes from the shortcodes tag.
+ *
+ * The attributes list has the attribute name as the key and the value of the
+ * attribute as the value in the key/value pair. This allows for easier
+ * retrieval of the attributes, since all attributes have to be known.
+ *
+ * @since 2.5
+ *
+ * @param string $text
+ * @return array List of attributes and their value.
+ */
+function shortcode_parse_atts($text) {
+ $atts = array();
+ $pattern = '/(\w+)\s*=\s*"([^"]*)"(?:\s|$)|(\w+)\s*=\s*\'([^\']*)\'(?:\s|$)|(\w+)\s*=\s*([^\s\'"]+)(?:\s|$)|"([^"]*)"(?:\s|$)|(\S+)(?:\s|$)/';
+ $text = preg_replace("/[\x{00a0}\x{200b}]+/u", " ", $text);
+ if ( preg_match_all($pattern, $text, $match, PREG_SET_ORDER) ) {
+ foreach ($match as $m) {
+ if (!empty($m[1]))
+ $atts[strtolower($m[1])] = stripcslashes($m[2]);
+ elseif (!empty($m[3]))
+ $atts[strtolower($m[3])] = stripcslashes($m[4]);
+ elseif (!empty($m[5]))
+ $atts[strtolower($m[5])] = stripcslashes($m[6]);
+ elseif (isset($m[7]) and strlen($m[7]))
+ $atts[] = stripcslashes($m[7]);
+ elseif (isset($m[8]))
+ $atts[] = stripcslashes($m[8]);
+ }
+ } else {
+ $atts = ltrim($text);
+ }
+ return $atts;
+}