/wp-includes/formatting.php

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<?php
/**
 * Main WordPress Formatting API.
 *
 * Handles many functions for formatting output.
 *
 * @package WordPress
 **/

/**
 * Replaces common plain text characters into formatted entities
 *
 * As an example,
 * <code>
 * 'cause today's effort makes it worth tomorrow's "holiday"...
 * </code>
 * Becomes:
 * <code>
 * &#8217;cause today&#8217;s effort makes it worth tomorrow&#8217;s &#8220;holiday&#8221;&#8230;
 * </code>
 * Code within certain html blocks are skipped.
 *
 * @since 0.71
 * @uses $wp_cockneyreplace Array of formatted entities for certain common phrases
 *
 * @param string $text The text to be formatted
 * @return string The string replaced with html entities
 */
function wptexturize($text) {
	global $wp_cockneyreplace;
	static $opening_quote, $closing_quote, $default_no_texturize_tags, $default_no_texturize_shortcodes, $static_characters, $static_replacements, $dynamic_characters, $dynamic_replacements;

	// No need to set up these static variables more than once
	if ( empty( $opening_quote ) ) {
		/* translators: opening curly quote */
		$opening_quote = _x('&#8220;', 'opening curly quote');
		/* translators: closing curly quote */
		$closing_quote = _x('&#8221;', 'closing curly quote');

		$default_no_texturize_tags = array('pre', 'code', 'kbd', 'style', 'script', 'tt');
		$default_no_texturize_shortcodes = array('code');

		// if a plugin has provided an autocorrect array, use it
		if ( isset($wp_cockneyreplace) ) {
			$cockney = array_keys($wp_cockneyreplace);
			$cockneyreplace = array_values($wp_cockneyreplace);
		} else {
			$cockney = array("'tain't","'twere","'twas","'tis","'twill","'til","'bout","'nuff","'round","'cause");
			$cockneyreplace = array("&#8217;tain&#8217;t","&#8217;twere","&#8217;twas","&#8217;tis","&#8217;twill","&#8217;til","&#8217;bout","&#8217;nuff","&#8217;round","&#8217;cause");
		}

		$static_characters = array_merge(array('---', ' -- ', '--', ' - ', 'xn&#8211;', '...', '``', '\'\'', ' (tm)'), $cockney);
		$static_replacements = array_merge(array('&#8212;', ' &#8212; ', '&#8211;', ' &#8211; ', 'xn--', '&#8230;', $opening_quote, $closing_quote, ' &#8482;'), $cockneyreplace);

		$dynamic_characters = array('/\'(\d\d(?:&#8217;|\')?s)/', '/\'(\d)/', '/(\s|\A|[([{<]|")\'/', '/(\d)"/', '/(\d)\'/', '/(\S)\'([^\'\s])/', '/(\s|\A|[([{<])"(?!\s)/', '/"(\s|\S|\Z)/', '/\'([\s.]|\Z)/', '/\b(\d+)x(\d+)\b/');
		$dynamic_replacements = array('&#8217;$1','&#8217;$1', '$1&#8216;', '$1&#8243;', '$1&#8242;', '$1&#8217;$2', '$1' . $opening_quote . '$2', $closing_quote . '$1', '&#8217;$1', '$1&#215;$2');
	}

	// Transform into regexp sub-expression used in _wptexturize_pushpop_element
	// Must do this everytime in case plugins use these filters in a context sensitive manner
	$no_texturize_tags = '(' . implode('|', apply_filters('no_texturize_tags', $default_no_texturize_tags) ) . ')';
	$no_texturize_shortcodes = '(' . implode('|', apply_filters('no_texturize_shortcodes', $default_no_texturize_shortcodes) ) . ')';

	$no_texturize_tags_stack = array();
	$no_texturize_shortcodes_stack = array();

	$textarr = preg_split('/(<.*>|\[.*\])/Us', $text, -1, PREG_SPLIT_DELIM_CAPTURE);

	foreach ( $textarr as &$curl ) {
		if ( empty( $curl ) )
			continue;

		// Only call _wptexturize_pushpop_element if first char is correct tag opening
		$first = $curl[0];
		if ( '<' === $first ) {
			_wptexturize_pushpop_element($curl, $no_texturize_tags_stack, $no_texturize_tags, '<', '>');
		} elseif ( '[' === $first ) {
			_wptexturize_pushpop_element($curl, $no_texturize_shortcodes_stack, $no_texturize_shortcodes, '[', ']');
		} elseif ( empty($no_texturize_shortcodes_stack) && empty($no_texturize_tags_stack) ) {
			// This is not a tag, nor is the texturization disabled static strings
			$curl = str_replace($static_characters, $static_replacements, $curl);
			// regular expressions
			$curl = preg_replace($dynamic_characters, $dynamic_replacements, $curl);
		}
		$curl = preg_replace('/&([^#])(?![a-zA-Z1-4]{1,8};)/', '&#038;$1', $curl);
	}
	return implode( '', $textarr );
}

/**
 * Search for disabled element tags. Push element to stack on tag open and pop
 * on tag close. Assumes first character of $text is tag opening.
 *
 * @access private
 * @since 2.9.0
 *
 * @param string $text Text to check. First character is assumed to be $opening
 * @param array $stack Array used as stack of opened tag elements
 * @param string $disabled_elements Tags to match against formatted as regexp sub-expression
 * @param string $opening Tag opening character, assumed to be 1 character long
 * @param string $opening Tag closing  character
 * @return object
 */
function _wptexturize_pushpop_element($text, &$stack, $disabled_elements, $opening = '<', $closing = '>') {
	// Check if it is a closing tag -- otherwise assume opening tag
	if (strncmp($opening . '/', $text, 2)) {
		// Opening? Check $text+1 against disabled elements
		if (preg_match('/^' . $disabled_elements . '\b/', substr($text, 1), $matches)) {
			/*
			 * This disables texturize until we find a closing tag of our type
			 * (e.g. <pre>) even if there was invalid nesting before that
			 *
			 * Example: in the case <pre>sadsadasd</code>"baba"</pre>
			 *          "baba" won't be texturize
			 */

			array_push($stack, $matches[1]);
		}
	} else {
		// Closing? Check $text+2 against disabled elements
		$c = preg_quote($closing, '/');
		if (preg_match('/^' . $disabled_elements . $c . '/', substr($text, 2), $matches)) {
			$last = array_pop($stack);

			// Make sure it matches the opening tag
			if ($last != $matches[1])
				array_push($stack, $last);
		}
	}
}

/**
 * Accepts matches array from preg_replace_callback in wpautop() or a string.
 *
 * Ensures that the contents of a <<pre>>...<</pre>> HTML block are not
 * converted into paragraphs or line-breaks.
 *
 * @since 1.2.0
 *
 * @param array|string $matches The array or string
 * @return string The pre block without paragraph/line-break conversion.
 */
function clean_pre($matches) {
	if ( is_array($matches) )
		$text = $matches[1] . $matches[2] . "</pre>";
	else
		$text = $matches;

	$text = str_replace('<br />', '', $text);
	$text = str_replace('<p>', "\n", $text);
	$text = str_replace('</p>', '', $text);

	return $text;
}

/**
 * Replaces double line-breaks with paragraph elements.
 *
 * A group of regex replaces used to identify text formatted with newlines and
 * replace double line-breaks with HTML paragraph tags. The remaining
 * line-breaks after conversion become <<br />> tags, unless $br is set to '0'
 * or 'false'.
 *
 * @since 0.71
 *
 * @param string $pee The text which has to be formatted.
 * @param int|bool $br Optional. If set, this will convert all remaining line-breaks after paragraphing. Default true.
 * @return string Text which has been converted into correct paragraph tags.
 */
function wpautop($pee, $br = 1) {

	if ( trim($pee) === '' )
		return '';
	$pee = $pee . "\n"; // just to make things a little easier, pad the end
	$pee = preg_replace('|<br />\s*<br />|', "\n\n", $pee);
	// Space things out a little
	$allblocks = '(?:table|thead|tfoot|caption|col|colgroup|tbody|tr|td|th|div|dl|dd|dt|ul|ol|li|pre|select|option|form|map|area|blockquote|address|math|style|input|p|h[1-6]|hr|fieldset|legend|section|article|aside|hgroup|header|footer|nav|figure|figcaption|details|menu|summary)';
	$pee = preg_replace('!(<' . $allblocks . '[^>]*>)!', "\n$1", $pee);
	$pee = preg_replace('!(</' . $allblocks . '>)!', "$1\n\n", $pee);
	$pee = str_replace(array("\r\n", "\r"), "\n", $pee); // cross-platform newlines
	if ( strpos($pee, '<object') !== false ) {
		$pee = preg_replace('|\s*<param([^>]*)>\s*|', "<param$1>", $pee); // no pee inside object/embed
		$pee = preg_replace('|\s*</embed>\s*|', '</embed>', $pee);
	}
	$pee = preg_replace("/\n\n+/", "\n\n", $pee); // take care of duplicates
	// make paragraphs, including one at the end
	$pees = preg_split('/\n\s*\n/', $pee, -1, PREG_SPLIT_NO_EMPTY);
	$pee = '';
	foreach ( $pees as $tinkle )
		$pee .= '<p>' . trim($tinkle, "\n") . "</p>\n";
	$pee = preg_replace('|<p>\s*</p>|', '', $pee); // under certain strange conditions it could create a P of entirely whitespace
	$pee = preg_replace('!<p>([^<]+)</(div|address|form)>!', "<p>$1</p></$2>", $pee);
	$pee = preg_replace('!<p>\s*(</?' . $allblocks . '[^>]*>)\s*</p>!', "$1", $pee); // don't pee all over a tag
	$pee = preg_replace("|<p>(<li.+?)</p>|", "$1", $pee); // problem with nested lists
	$pee = preg_replace('|<p><blockquote([^>]*)>|i', "<blockquote$1><p>", $pee);
	$pee = str_replace('</blockquote></p>', '</p></blockquote>', $pee);
	$pee = preg_replace('!<p>\s*(</?' . $allblocks . '[^>]*>)!', "$1", $pee);
	$pee = preg_replace('!(</?' . $allblocks . '[^>]*>)\s*</p>!', "$1", $pee);
	if ($br) {
		$pee = preg_replace_callback('/<(script|style).*?<\/\\1>/s', '_autop_newline_preservation_helper', $pee);
		$pee = preg_replace('|(?<!<br />)\s*\n|', "<br />\n", $pee); // optionally make line breaks
		$pee = str_replace('<WPPreserveNewline />', "\n", $pee);
	}
	$pee = preg_replace('!(</?' . $allblocks . '[^>]*>)\s*<br />!', "$1", $pee);
	$pee = preg_replace('!<br />(\s*</?(?:p|li|div|dl|dd|dt|th|pre|td|ul|ol)[^>]*>)!', '$1', $pee);
	if (strpos($pee, '<pre') !== false)
		$pee = preg_replace_callback('!(<pre[^>]*>)(.*?)</pre>!is', 'clean_pre', $pee );
	$pee = preg_replace( "|\n</p>$|", '</p>', $pee );

	return $pee;
}

/**
 * Newline preservation help function for wpautop
 *
 * @since 3.1.0
 * @access private
 * @param array $matches preg_replace_callback matches array
 * @returns string
 */
function _autop_newline_preservation_helper( $matches ) {
	return str_replace("\n", "<WPPreserveNewline />", $matches[0]);
}

/**
 * Don't auto-p wrap shortcodes that stand alone
 *
 * Ensures that shortcodes are not wrapped in <<p>>...<</p>>.
 *
 * @since 2.9.0
 *
 * @param string $pee The content.
 * @return string The filtered content.
 */
function shortcode_unautop($pee) {
	global $shortcode_tags;

	if ( !empty($shortcode_tags) && is_array($shortcode_tags) ) {
		$tagnames = array_keys($shortcode_tags);
		$tagregexp = join( '|', array_map('preg_quote', $tagnames) );
		$pee = preg_replace('/<p>\\s*?(\\[(' . $tagregexp . ')\\b.*?\\/?\\](?:.+?\\[\\/\\2\\])?)\\s*<\\/p>/s', '$1', $pee);
	}

	return $pee;
}

/**
 * Checks to see if a string is utf8 encoded.
 *
 * NOTE: This function checks for 5-Byte sequences, UTF8
 *       has Bytes Sequences with a maximum length of 4.
 *
 * @author bmorel at ssi dot fr (modified)
 * @since 1.2.1
 *
 * @param string $str The string to be checked
 * @return bool True if $str fits a UTF-8 model, false otherwise.
 */
function seems_utf8($str) {
	$length = strlen($str);
	for ($i=0; $i < $length; $i++) {
		$c = ord($str[$i]);
		if ($c < 0x80) $n = 0; # 0bbbbbbb
		elseif (($c & 0xE0) == 0xC0) $n=1; # 110bbbbb
		elseif (($c & 0xF0) == 0xE0) $n=2; # 1110bbbb
		elseif (($c & 0xF8) == 0xF0) $n=3; # 11110bbb
		elseif (($c & 0xFC) == 0xF8) $n=4; # 111110bb
		elseif (($c & 0xFE) == 0xFC) $n=5; # 1111110b
		else return false; # Does not match any model
		for ($j=0; $j<$n; $j++) { # n bytes matching 10bbbbbb follow ?
			if ((++$i == $length) || ((ord($str[$i]) & 0xC0) != 0x80))
				return false;
		}
	}
	return true;
}

/**
 * Converts a number of special characters into their HTML entities.
 *
 * Specifically deals with: &, <, >, ", and '.
 *
 * $quote_style can be set to ENT_COMPAT to encode " to
 * &quot;, or ENT_QUOTES to do both. Default is ENT_NOQUOTES where no quotes are encoded.
 *
 * @since 1.2.2
 *
 * @param string $string The text which is to be encoded.
 * @param mixed $quote_style Optional. Converts double quotes if set to ENT_COMPAT, both single and double if set to ENT_QUOTES or none if set to ENT_NOQUOTES. Also compatible with old values; converting single quotes if set to 'single', double if set to 'double' or both if otherwise set. Default is ENT_NOQUOTES.
 * @param string $charset Optional. The character encoding of the string. Default is false.
 * @param boolean $double_encode Optional. Whether to encode existing html entities. Default is false.
 * @return string The encoded text with HTML entities.
 */
function _wp_specialchars( $string, $quote_style = ENT_NOQUOTES, $charset = false, $double_encode = false ) {
	$string = (string) $string;

	if ( 0 === strlen( $string ) ) {
		return '';
	}

	// Don't bother if there are no specialchars - saves some processing
	if ( !preg_match( '/[&<>"\']/', $string ) ) {
		return $string;
	}

	// Account for the previous behaviour of the function when the $quote_style is not an accepted value
	if ( empty( $quote_style ) ) {
		$quote_style = ENT_NOQUOTES;
	} elseif ( !in_array( $quote_style, array( 0, 2, 3, 'single', 'double' ), true ) ) {
		$quote_style = ENT_QUOTES;
	}

	// Store the site charset as a static to avoid multiple calls to wp_load_alloptions()
	if ( !$charset ) {
		static $_charset;
		if ( !isset( $_charset ) ) {
			$alloptions = wp_load_alloptions();
			$_charset = isset( $alloptions['blog_charset'] ) ? $alloptions['blog_charset'] : '';
		}
		$charset = $_charset;
	}
	if ( in_array( $charset, array( 'utf8', 'utf-8', 'UTF8' ) ) ) {
		$charset = 'UTF-8';
	}

	$_quote_style = $quote_style;

	if ( $quote_style === 'double' ) {
		$quote_style = ENT_COMPAT;
		$_quote_style = ENT_COMPAT;
	} elseif ( $quote_style === 'single' ) {
		$quote_style = ENT_NOQUOTES;
	}

	// Handle double encoding ourselves
	if ( !$double_encode ) {
		$string = wp_specialchars_decode( $string, $_quote_style );

		/* Critical */
		// The previous line decodes &amp;phrase; into &phrase;  We must guarantee that &phrase; is valid before proceeding.
		$string = wp_kses_normalize_entities($string);

		// Now proceed with custom double-encoding silliness
		$string = preg_replace( '/&(#?x?[0-9a-z]+);/i', '|wp_entity|$1|/wp_entity|', $string );
	}

	$string = @htmlspecialchars( $string, $quote_style, $charset );

	// Handle double encoding ourselves
	if ( !$double_encode ) {
		$string = str_replace( array( '|wp_entity|', '|/wp_entity|' ), array( '&', ';' ), $string );
	}

	// Backwards compatibility
	if ( 'single' === $_quote_style ) {
		$string = str_replace( "'", '&#039;', $string );
	}

	return $string;
}

/**
 * Converts a number of HTML entities into their special characters.
 *
 * Specifically deals with: &, <, >, ", and '.
 *
 * $quote_style can be set to ENT_COMPAT to decode " entities,
 * or ENT_QUOTES to do both " and '. Default is ENT_NOQUOTES where no quotes are decoded.
 *
 * @since 2.8
 *
 * @param string $string The text which is to be decoded.
 * @param mixed $quote_style Optional. Converts double quotes if set to ENT_COMPAT, both single and double if set to ENT_QUOTES or none if set to ENT_NOQUOTES. Also compatible with old _wp_specialchars() values; converting single quotes if set to 'single', double if set to 'double' or both if otherwise set. Default is ENT_NOQUOTES.
 * @return string The decoded text without HTML entities.
 */
function wp_specialchars_decode( $string, $quote_style = ENT_NOQUOTES ) {
	$string = (string) $string;

	if ( 0 === strlen( $string ) ) {
		return '';
	}

	// Don't bother if there are no entities - saves a lot of processing
	if ( strpos( $string, '&' ) === false ) {
		return $string;
	}

	// Match the previous behaviour of _wp_specialchars() when the $quote_style is not an accepted value
	if ( empty( $quote_style ) ) {
		$quote_style = ENT_NOQUOTES;
	} elseif ( !in_array( $quote_style, array( 0, 2, 3, 'single', 'double' ), true ) ) {
		$quote_style = ENT_QUOTES;
	}

	// More complete than get_html_translation_table( HTML_SPECIALCHARS )
	$single = array( '&#039;'  => '\'', '&#x27;' => '\'' );
	$single_preg = array( '/&#0*39;/'  => '&#039;', '/&#x0*27;/i' => '&#x27;' );
	$double = array( '&quot;' => '"', '&#034;'  => '"', '&#x22;' => '"' );
	$double_preg = array( '/&#0*34;/'  => '&#034;', '/&#x0*22;/i' => '&#x22;' );
	$others = array( '&lt;'   => '<', '&#060;'  => '<', '&gt;'   => '>', '&#062;'  => '>', '&amp;'  => '&', '&#038;'  => '&', '&#x26;' => '&' );
	$others_preg = array( '/&#0*60;/'  => '&#060;', '/&#0*62;/'  => '&#062;', '/&#0*38;/'  => '&#038;', '/&#x0*26;/i' => '&#x26;' );

	if ( $quote_style === ENT_QUOTES ) {
		$translation = array_merge( $single, $double, $others );
		$translation_preg = array_merge( $single_preg, $double_preg, $others_preg );
	} elseif ( $quote_style === ENT_COMPAT || $quote_style === 'double' ) {
		$translation = array_merge( $double, $others );
		$translation_preg = array_merge( $double_preg, $others_preg );
	} elseif ( $quote_style === 'single' ) {
		$translation = array_merge( $single, $others );
		$translation_preg = array_merge( $single_preg, $others_preg );
	} elseif ( $quote_style === ENT_NOQUOTES ) {
		$translation = $others;
		$translation_preg = $others_preg;
	}

	// Remove zero padding on numeric entities
	$string = preg_replace( array_keys( $translation_preg ), array_values( $translation_preg ), $string );

	// Replace characters according to translation table
	return strtr( $string, $translation );
}

/**
 * Checks for invalid UTF8 in a string.
 *
 * @since 2.8
 *
 * @param string $string The text which is to be checked.
 * @param boolean $strip Optional. Whether to attempt to strip out invalid UTF8. Default is false.
 * @return string The checked text.
 */
function wp_check_invalid_utf8( $string, $strip = false ) {
	$string = (string) $string;

	if ( 0 === strlen( $string ) ) {
		return '';
	}

	// Store the site charset as a static to avoid multiple calls to get_option()
	static $is_utf8;
	if ( !isset( $is_utf8 ) ) {
		$is_utf8 = in_array( get_option( 'blog_charset' ), array( 'utf8', 'utf-8', 'UTF8', 'UTF-8' ) );
	}
	if ( !$is_utf8 ) {
		return $string;
	}

	// Check for support for utf8 in the installed PCRE library once and store the result in a static
	static $utf8_pcre;
	if ( !isset( $utf8_pcre ) ) {
		$utf8_pcre = @preg_match( '/^./u', 'a' );
	}
	// We can't demand utf8 in the PCRE installation, so just return the string in those cases
	if ( !$utf8_pcre ) {
		return $string;
	}

	// preg_match fails when it encounters invalid UTF8 in $string
	if ( 1 === @preg_match( '/^./us', $string ) ) {
		return $string;
	}

	// Attempt to strip the bad chars if requested (not recommended)
	if ( $strip && function_exists( 'iconv' ) ) {
		return iconv( 'utf-8', 'utf-8', $string );
	}

	return '';
}

/**
 * Encode the Unicode values to be used in the URI.
 *
 * @since 1.5.0
 *
 * @param string $utf8_string
 * @param int $length Max length of the string
 * @return string String with Unicode encoded for URI.
 */
function utf8_uri_encode( $utf8_string, $length = 0 ) {
	$unicode = '';
	$values = array();
	$num_octets = 1;
	$unicode_length = 0;

	$string_length = strlen( $utf8_string );
	for ($i = 0; $i < $string_length; $i++ ) {

		$value = ord( $utf8_string[ $i ] );

		if ( $value < 128 ) {
			if ( $length && ( $unicode_length >= $length ) )
				break;
			$unicode .= chr($value);
			$unicode_length++;
		} else {
			if ( count( $values ) == 0 ) $num_octets = ( $value < 224 ) ? 2 : 3;

			$values[] = $value;

			if ( $length && ( $unicode_length + ($num_octets * 3) ) > $length )
				break;
			if ( count( $values ) == $num_octets ) {
				if ($num_octets == 3) {
					$unicode .= '%' . dechex($values[0]) . '%' . dechex($values[1]) . '%' . dechex($values[2]);
					$unicode_length += 9;
				} else {
					$unicode .= '%' . dechex($values[0]) . '%' . dechex($values[1]);
					$unicode_length += 6;
				}

				$values = array();
				$num_octets = 1;
			}
		}
	}

	return $unicode;
}

/**
 * Converts all accent characters to ASCII characters.
 *
 * If there are no accent characters, then the string given is just returned.
 *
 * @since 1.2.1
 *
 * @param string $string Text that might have accent characters
 * @return string Filtered string with replaced "nice" characters.
 */
function remove_accents($string) {
	if ( !preg_match('/[\x80-\xff]/', $string) )
		return $string;

	if (seems_utf8($string)) {
		$chars = array(
		// Decompositions for Latin-1 Supplement
		chr(195).chr(128) => 'A', chr(195).chr(129) => 'A',
		chr(195).chr(130) => 'A', chr(195).chr(131) => 'A',
		chr(195).chr(132) => 'A', chr(195).chr(133) => 'A',
		chr(195).chr(134) => 'AE',chr(195).chr(135) => 'C',
		chr(195).chr(136) => 'E', chr(195).chr(137) => 'E',
		chr(195).chr(138) => 'E', chr(195).chr(139) => 'E',
		chr(195).chr(140) => 'I', chr(195).chr(141) => 'I',
		chr(195).chr(142) => 'I', chr(195).chr(143) => 'I',
		chr(195).chr(144) => 'D', chr(195).chr(145) => 'N',
		chr(195).chr(146) => 'O', chr(195).chr(147) => 'O',
		chr(195).chr(148) => 'O', chr(195).chr(149) => 'O',
		chr(195).chr(150) => 'O', chr(195).chr(153) => 'U',
		chr(195).chr(154) => 'U', chr(195).chr(155) => 'U',
		chr(195).chr(156) => 'U', chr(195).chr(157) => 'Y',
		chr(195).chr(158) => 'TH',chr(195).chr(159) => 's',
		chr(195).chr(160) => 'a', chr(195).chr(161) => 'a',
		chr(195).chr(162) => 'a', chr(195).chr(163) => 'a',
		chr(195).chr(164) => 'a', chr(195).chr(165) => 'a',
		chr(195).chr(166) => 'ae',chr(195).chr(167) => 'c',
		chr(195).chr(168) => 'e', chr(195).chr(169) => 'e',
		chr(195).chr(170) => 'e', chr(195).chr(171) => 'e',
		chr(195).chr(172) => 'i', chr(195).chr(173) => 'i',
		chr(195).chr(174) => 'i', chr(195).chr(175) => 'i',
		chr(195).chr(176) => 'd', chr(195).chr(177) => 'n',
		chr(195).chr(178) => 'o', chr(195).chr(179) => 'o',
		chr(195).chr(180) => 'o', chr(195).chr(181) => 'o',
		chr(195).chr(182) => 'o', chr(195).chr(184) => 'o',
		chr(195).chr(185) => 'u', chr(195).chr(186) => 'u',
		chr(195).chr(187) => 'u', chr(195).chr(188) => 'u',
		chr(195).chr(189) => 'y', chr(195).chr(190) => 'th',
		chr(195).chr(191) => 'y',
		// Decompositions for Latin Extended-A
		chr(196).chr(128) => 'A', chr(196).chr(129) => 'a',
		chr(196).chr(130) => 'A', chr(196).chr(131) => 'a',
		chr(196).chr(132) => 'A', chr(196).chr(133) => 'a',
		chr(196).chr(134) => 'C', chr(196).chr(135) => 'c',
		chr(196).chr(136) => 'C', chr(196).chr(137) => 'c',
		chr(196).chr(138) => 'C', chr(196).chr(139) => 'c',
		chr(196).chr(140) => 'C', chr(196).chr(141) => 'c',
		chr(196).chr(142) => 'D', chr(196).chr(143) => 'd',
		chr(196).chr(144) => 'D', chr(196).chr(145) => 'd',
		chr(196).chr(146) => 'E', chr(196).chr(147) => 'e',
		chr(196).chr(148) => 'E', chr(196).chr(149) => 'e',
		chr(196).chr(150) => 'E', chr(196).chr(151) => 'e',
		chr(196).chr(152) => 'E', chr(196).chr(153) => 'e',
		chr(196).chr(154) => 'E', chr(196).chr(155) => 'e',
		chr(196).chr(156) => 'G', chr(196).chr(157) => 'g',
		chr(196).chr(158) => 'G', chr(196).chr(159) => 'g',
		chr(196).chr(160) => 'G', chr(196).chr(161) => 'g',
		chr(196).chr(162) => 'G', chr(196).chr(163) => 'g',
		chr(196).chr(164) => 'H', chr(196).chr(165) => 'h',
		chr(196).chr(166) => 'H', chr(196).chr(167) => 'h',
		chr(196).chr(168) => 'I', chr(196).chr(169) => 'i',
		chr(196).chr(170) => 'I', chr(196).chr(171) => 'i',
		chr(196).chr(172) => 'I', chr(196).chr(173) => 'i',
		chr(196).chr(174) => 'I', chr(196).chr(175) => 'i',
		chr(196).chr(176) => 'I', chr(196).chr(177) => 'i',
		chr(196).chr(178) => 'IJ',chr(196).chr(179) => 'ij',
		chr(196).chr(180) => 'J', chr(196).chr(181) => 'j',
		chr(196).chr(182) => 'K', chr(196).chr(183) => 'k',
		chr(196).chr(184) => 'k', chr(196).chr(185) => 'L',
		chr(196).chr(186) => 'l', chr(196).chr(187) => 'L',
		chr(196).chr(188) => 'l', chr(196).chr(189) => 'L',
		chr(196).chr(190) => 'l', chr(196).chr(191) => 'L',
		chr(197).chr(128) => 'l', chr(197).chr(129) => 'L',
		chr(197).chr(130) => 'l', chr(197).chr(131) => 'N',
		chr(197).chr(132) => 'n', chr(197).chr(133) => 'N',
		chr(197).chr(134) => 'n', chr(197).chr(135) => 'N',
		chr(197).chr(136) => 'n', chr(197).chr(137) => 'N',
		chr(197).chr(138) => 'n', chr(197).chr(139) => 'N',
		chr(197).chr(140) => 'O', chr(197).chr(141) => 'o',
		chr(197).chr(142) => 'O', chr(197).chr(143) => 'o',
		chr(197).chr(144) => 'O', chr(197).chr(145) => 'o',
		chr(197).chr(146) => 'OE',chr(197).chr(147) => 'oe',
		chr(197).chr(148) => 'R',chr(197).chr(149) => 'r',
		chr(197).chr(150) => 'R',chr(197).chr(151) => 'r',
		chr(197).chr(152) => 'R',chr(197).chr(153) => 'r',
		chr(197).chr(154) => 'S',chr(197).chr(155) => 's',
		chr(197).chr(156) => 'S',chr(197).chr(157) => 's',
		chr(197).chr(158) => 'S',chr(197).chr(159) => 's',
		chr(197).chr(160) => 'S', chr(197).chr(161) => 's',
		chr(197).chr(162) => 'T', chr(197).chr(163) => 't',
		chr(197).chr(164) => 'T', chr(197).chr(165) => 't',
		chr(197).chr(166) => 'T', chr(197).chr(167) => 't',
		chr(197).chr(168) => 'U', chr(197).chr(169) => 'u',
		chr(197).chr(170) => 'U', chr(197).chr(171) => 'u',
		chr(197).chr(172) => 'U', chr(197).chr(173) => 'u',
		chr(197).chr(174) => 'U', chr(197).chr(175) => 'u',
		chr(197).chr(176) => 'U', chr(197).chr(177) => 'u',
		chr(197).chr(178) => 'U', chr(197).chr(179) => 'u',
		chr(197).chr(180) => 'W', chr(197).chr(181) => 'w',
		chr(197).chr(182) => 'Y', chr(197).chr(183) => 'y',
		chr(197).chr(184) => 'Y', chr(197).chr(185) => 'Z',
		chr(197).chr(186) => 'z', chr(197).chr(187) => 'Z',
		chr(197).chr(188) => 'z', chr(197).chr(189) => 'Z',
		chr(197).chr(190) => 'z', chr(197).chr(191) => 's',
		// Decompositions for Latin Extended-B
		chr(200).chr(152) => 'S', chr(200).chr(153) => 's',
		chr(200).chr(154) => 'T', chr(200).chr(155) => 't',
		// Euro Sign
		chr(226).chr(130).chr(172) => 'E',
		// GBP (Pound) Sign
		chr(194).chr(163) => '');

		$string = strtr($string, $chars);
	} else {
		// Assume ISO-8859-1 if not UTF-8
		$chars['in'] = chr(128).chr(131).chr(138).chr(142).chr(154).chr(158)
			.chr(159).chr(162).chr(165).chr(181).chr(192).chr(193).chr(194)
			.chr(195).chr(196).chr(197).chr(199).chr(200).chr(201).chr(202)
			.chr(203).chr(204).chr(205).chr(206).chr(207).chr(209).chr(210)
			.chr(211).chr(212).chr(213).chr(214).chr(216).chr(217).chr(218)
			.chr(219).chr(220).chr(221).chr(224).chr(225).chr(226).chr(227)
			.chr(228).chr(229).chr(231).chr(232).chr(233).chr(234).chr(235)
			.chr(236).chr(237).chr(238).chr(239).chr(241).chr(242).chr(243)
			.chr(244).chr(245).chr(246).chr(248).chr(249).chr(250).chr(251)
			.chr(252).chr(253).chr(255);

		$chars['out'] = "EfSZszYcYuAAAAAACEEEEIIIINOOOOOOUUUUYaaaaaaceeeeiiiinoooooouuuuyy";

		$string = strtr($string, $chars['in'], $chars['out']);
		$double_chars['in'] = array(chr(140), chr(156), chr(198), chr(208), chr(222), chr(223), chr(230), chr(240), chr(254));
		$double_chars['out'] = array('OE', 'oe', 'AE', 'DH', 'TH', 'ss', 'ae', 'dh', 'th');
		$string = str_replace($double_chars['in'], $double_chars['out'], $string);
	}

	return $string;
}

/**
 * Sanitizes a filename replacing whitespace with dashes
 *
 * Removes special characters that are illegal in filenames on certain
 * operating systems and special characters requiring special escaping
 * to manipulate at the command line. Replaces spaces and consecutive
 * dashes with a single dash. Trim period, dash and underscore from beginning
 * and end of filename.
 *
 * @since 2.1.0
 *
 * @param string $filename The filename to be sanitized
 * @return string The sanitized filename
 */
function sanitize_file_name( $filename ) {
	$filename_raw = $filename;
	$special_chars = array("?", "[", "]", "/", "\\", "=", "<", ">", ":", ";", ",", "'", "\"", "&", "$", "#", "*", "(", ")", "|", "~", "`", "!", "{", "}", chr(0));
	$special_chars = apply_filters('sanitize_file_name_chars', $special_chars, $filename_raw);
	$filename = str_replace($special_chars, '', $filename);
	$filename = preg_replace('/[\s-]+/', '-', $filename);
	$filename = trim($filename, '.-_');

	// Split the filename into a base and extension[s]
	$parts = explode('.', $filename);

	// Return if only one extension
	if ( count($parts) <= 2 )
		return apply_filters('sanitize_file_name', $filename, $filename_raw);

	// Process multiple extensions
	$filename = array_shift($parts);
	$extension = array_pop($parts);
	$mimes = get_allowed_mime_types();

	// Loop over any intermediate extensions.  Munge them with a trailing underscore if they are a 2 - 5 character
	// long alpha string not in the extension whitelist.
	foreach ( (array) $parts as $part) {
		$filename .= '.' . $part;

		if ( preg_match("/^[a-zA-Z]{2,5}\d?$/", $part) ) {
			$allowed = false;
			foreach ( $mimes as $ext_preg => $mime_match ) {
				$ext_preg = '!^(' . $ext_preg . ')$!i';
				if ( preg_match( $ext_preg, $part ) ) {
					$allowed = true;
					break;
				}
			}
			if ( !$allowed )
				$filename .= '_';
		}
	}
	$filename .= '.' . $extension;

	return apply_filters('sanitize_file_name', $filename, $filename_raw);
}

/**
 * Sanitize username stripping out unsafe characters.
 *
 * Removes tags, octets, entities, and if strict is enabled, will only keep
 * alphanumeric, _, space, ., -, @. After sanitizing, it passes the username,
 * raw username (the username in the parameter), and the value of $strict as
 * parameters for the 'sanitize_user' filter.
 *
 * @since 2.0.0
 * @uses apply_filters() Calls 'sanitize_user' hook on username, raw username,
 *		and $strict parameter.
 *
 * @param string $username The username to be sanitized.
 * @param bool $strict If set limits $username to specific characters. Default false.
 * @return string The sanitized username, after passing through filters.
 */
function sanitize_user( $username, $strict = false ) {
	$raw_username = $username;
	$username = wp_strip_all_tags( $username );
	$username = remove_accents( $username );
	// Kill octets
	$username = preg_replace( '|%([a-fA-F0-9][a-fA-F0-9])|', '', $username );
	$username = preg_replace( '/&.+?;/', '', $username ); // Kill entities

	// If strict, reduce to ASCII for max portability.
	if ( $strict )
		$username = preg_replace( '|[^a-z0-9 _.\-@]|i', '', $username );

	$username = trim( $username );
	// Consolidate contiguous whitespace
	$username = preg_replace( '|\s+|', ' ', $username );

	return apply_filters( 'sanitize_user', $username, $raw_username, $strict );
}

/**
 * Sanitize a string key.
 *
 * Keys are used as internal identifiers. Lowercase alphanumeric characters, dashes and underscores are allowed.
 *
 * @since 3.0.0
 *
 * @param string $key String key
 * @return string Sanitized key
 */
function sanitize_key( $key ) {
	$raw_key = $key;
	$key = strtolower( $key );
	$key = preg_replace( '/[^a-z0-9_\-]/', '', $key );
	return apply_filters( 'sanitize_key', $key, $raw_key );
}

/**
 * Sanitizes title or use fallback title.
 *
 * Specifically, HTML and PHP tags are stripped. Further actions can be added
 * via the plugin API. If $title is empty and $fallback_title is set, the latter
 * will be used.
 *
 * @since 1.0.0
 *
 * @param string $title The string to be sanitized.
 * @param string $fallback_title Optional. A title to use if $title is empty.
 * @param string $context Optional. The operation for which the string is sanitized
 * @return string The sanitized string.
 */
function sanitize_title($title, $fallback_title = '', $context = 'save') {
	$raw_title = $title;

	if ( 'save' == $context )
		$title = remove_accents($title);

	$title = apply_filters('sanitize_title', $title, $raw_title, $context);

	if ( '' === $title || false === $title )
		$title = $fallback_title;

	return $title;
}

function sanitize_title_for_query($title) {
	return sanitize_title($title, '', 'query');
}

/**
 * Sanitizes title, replacing whitespace with dashes.
 *
 * Limits the output to alphanumeric characters, underscore (_) and dash (-).
 * Whitespace becomes a dash.
 *
 * @since 1.2.0
 *
 * @param string $title The title to be sanitized.
 * @return string The sanitized title.
 */
function sanitize_title_with_dashes($title) {
	$title = strip_tags($title);
	// Preserve escaped octets.
	$title = preg_replace('|%([a-fA-F0-9][a-fA-F0-9])|', '---$1---', $title);
	// Remove percent signs that are not part of an octet.
	$title = str_replace('%', '', $title);
	// Restore octets.
	$title = preg_replace('|---([a-fA-F0-9][a-fA-F0-9])---|', '%$1', $title);

	if (seems_utf8($title)) {
		if (function_exists('mb_strtolower')) {
			$title = mb_strtolower($title, 'UTF-8');
		}
		$title = utf8_uri_encode($title, 200);
	}

	$title = strtolower($title);
	$title = preg_replace('/&.+?;/', '', $title); // kill entities
	$title = str_replace('.', '-', $title);
	$title = preg_replace('/[^%a-z0-9 _-]/', '', $title);
	$title = preg_replace('/\s+/', '-', $title);
	$title = preg_replace('|-+|', '-', $title);
	$title = trim($title, '-');

	return $title;
}

/**
 * Ensures a string is a valid SQL order by clause.
 *
 * Accepts one or more columns, with or without ASC/DESC, and also accepts
 * RAND().
 *
 * @since 2.5.1
 *
 * @param string $orderby Order by string to be checked.
 * @return string|false Returns the order by clause if it is a match, false otherwise.
 */
function sanitize_sql_orderby( $orderby ){
	preg_match('/^\s*([a-z0-9_]+(\s+(ASC|DESC))?(\s*,\s*|\s*$))+|^\s*RAND\(\s*\)\s*$/i', $orderby, $obmatches);
	if ( !$obmatches )
		return false;
	return $orderby;
}

/**
 * Santizes a html classname to ensure it only contains valid characters
 *
 * Strips the string down to A-Z,a-z,0-9,_,-. If this results in an empty
 * string then it will return the alternative value supplied.
 *
 * @todo Expand to support the full range of CDATA that a class attribute can contain.
 *
 * @since 2.8.0
 *
 * @param string $class The classname to be sanitized
 * @param string $fallback Optional. The value to return if the sanitization end's up as an empty string.
 * 	Defaults to an empty string.
 * @return string The sanitized value
 */
function sanitize_html_class( $class, $fallback = '' ) {
	//Strip out any % encoded octets
	$sanitized = preg_replace( '|%[a-fA-F0-9][a-fA-F0-9]|', '', $class );

	//Limit to A-Z,a-z,0-9,_,-
	$sanitized = preg_replace( '/[^A-Za-z0-9_-]/', '', $sanitized );

	if ( '' == $sanitized )
		$sanitized = $fallback;

	return apply_filters( 'sanitize_html_class', $sanitized, $class, $fallback );
}

/**
 * Converts a number of characters from a string.
 *
 * Metadata tags <<title>> and <<category>> are removed, <<br>> and <<hr>> are
 * converted into correct XHTML and Unicode characters are converted to the
 * valid range.
 *
 * @since 0.71
 *
 * @param string $content String of characters to be converted.
 * @param string $deprecated Not used.
 * @return string Converted string.
 */
function convert_chars($content, $deprecated = '') {
	if ( !empty( $deprecated ) )
		_deprecated_argument( __FUNCTION__, '0.71' );

	// Translation of invalid Unicode references range to valid range
	$wp_htmltranswinuni = array(
	'&#128;' => '&#8364;', // the Euro sign
	'&#129;' => '',
	'&#130;' => '&#8218;', // these are Windows CP1252 specific characters
	'&#131;' => '&#402;',  // they would look weird on non-Windows browsers
	'&#132;' => '&#8222;',
	'&#133;' => '&#8230;',
	'&#134;' => '&#8224;',
	'&#135;' => '&#8225;',
	'&#136;' => '&#710;',
	'&#137;' => '&#8240;',
	'&#138;' => '&#352;',
	'&#139;' => '&#8249;',
	'&#140;' => '&#338;',
	'&#141;' => '',
	'&#142;' => '&#382;',
	'&#143;' => '',
	'&#144;' => '',
	'&#145;' => '&#8216;',
	'&#146;' => '&#8217;',
	'&#147;' => '&#8220;',
	'&#148;' => '&#8221;',
	'&#149;' => '&#8226;',
	'&#150;' => '&#8211;',
	'&#151;' => '&#8212;',
	'&#152;' => '&#732;',
	'&#153;' => '&#8482;',
	'&#154;' => '&#353;',
	'&#155;' => '&#8250;',
	'&#156;' => '&#339;',
	'&#157;' => '',
	'&#158;' => '',
	'&#159;' => '&#376;'
	);

	// Remove metadata tags
	$content = preg_replace('/<title>(.+?)<\/title>/','',$content);
	$content = preg_replace('/<category>(.+?)<\/category>/','',$content);

	// Converts lone & characters into &#38; (a.k.a. &amp;)
	$content = preg_replace('/&([^#])(?![a-z1-4]{1,8};)/i', '&#038;$1', $content);

	// Fix Word pasting
	$content = strtr($content, $wp_htmltranswinuni);

	// Just a little XHTML help
	$content = str_replace('<br>', '<br />', $content);
	$content = str_replace('<hr>', '<hr />', $content);

	return $content;
}

/**
 * Will only balance the tags if forced to and the option is set to balance tags.
 *
 * The option 'use_balanceTags' is used for whether the tags will be balanced.
 * Both the $force parameter and 'use_balanceTags' option will have to be true
 * before the tags will be balanced.
 *
 * @since 0.71
 *
 * @param string $text Text to be balanced
 * @param bool $force Forces balancing, ignoring the value of the option. Default false.
 * @return string Balanced text
 */
function balanceTags( $text, $force = false ) {
	if ( !$force && get_option('use_balanceTags') == 0 )
		return $text;
	return force_balance_tags( $text );
}

/**
 * Balances tags of string using a modified stack.
 *
 * @since 2.0.4
 *
 * @author Leonard Lin <leonard@acm.org>
 * @license GPL
 * @copyright November 4, 2001
 * @version 1.1
 * @todo Make better - change loop condition to $text in 1.2
 * @internal Modified by Scott Reilly (coffee2code) 02 Aug 2004
 *		1.1  Fixed handling of append/stack pop order of end text
 *			 Added Cleaning Hooks
 *		1.0  First Version
 *
 * @param string $text Text to be balanced.
 * @return string Balanced text.
 */
function force_balance_tags( $text ) {
	$tagstack = array();
	$stacksize = 0;
	$tagqueue = '';
	$newtext = '';
	$single_tags = array('br', 'hr', 'img', 'input'); // Known single-entity/self-closing tags
	$nestable_tags = array('blockquote', 'div', 'span'); // Tags that can be immediately nested within themselves

	// WP bug fix for comments - in case you REALLY meant to type '< !--'
	$text = str_replace('< !--', '<    !--', $text);
	// WP bug fix for LOVE <3 (and other situations with '<' before a number)
	$text = preg_replace('#<([0-9]{1})#', '&lt;$1', $text);

	while ( preg_match("/<(\/?[\w:]*)\s*([^>]*)>/", $text, $regex) ) {
		$newtext .= $tagqueue;

		$i = strpos($text, $regex[0]);
		$l = strlen($regex[0]);

		// clear the shifter
		$tagqueue = '';
		// Pop or Push
		if ( isset($regex[1][0]) && '/' == $regex[1][0] ) { // End Tag
			$tag = strtolower(substr($regex[1],1));
			// if too many closing tags
			if( $stacksize <= 0 ) {
				$tag = '';
				// or close to be safe $tag = '/' . $tag;
			}
			// if stacktop value = tag close value then pop
			else if ( $tagstack[$stacksize - 1] == $tag ) { // found closing tag
				$tag = '</' . $tag . '>'; // Close Tag
				// Pop
				array_pop( $tagstack );
				$stacksize--;
			} else { // closing tag not at top, search for it
				for ( $j = $stacksize-1; $j >= 0; $j-- ) {
					if ( $tagstack[$j] == $tag ) {
					// add tag to tagqueue
						for ( $k = $stacksize-1; $k >= $j; $k--) {
							$tagqueue .= '</' . array_pop( $tagstack ) . '>';
							$stacksize--;
						}
						break;
					}
				}
				$tag = '';
			}
		} else { // Begin Tag
			$tag = strtolower($regex[1]);

			// Tag Cleaning

			// If self-closing or '', don't do anything.
			if ( substr($regex[2],-1) == '/' || $tag == '' ) {
				// do nothing
			}
			// ElseIf it's a known single-entity tag but it doesn't close itself, do so
			elseif ( in_array($tag, $single_tags) ) {
				$regex[2] .= '/';
			} else {	// Push the tag onto the stack
				// If the top of the stack is the same as the tag we want to push, close previous tag
				if ( $stacksize > 0 && !in_array($tag, $nestable_tags) && $tagstack[$stacksize - 1] == $tag ) {
					$tagqueue = '</' . array_pop ($tagstack) . '>';
					$stacksize--;
				}
				$stacksize = array_push ($tagstack, $tag);
			}

			// Attributes
			$attributes = $regex[2];
			if( !empty($attributes) )
				$attributes = ' '.$attributes;

			$tag = '<' . $tag . $attributes . '>';
			//If already queuing a close tag, then put this tag on, too
			if ( !empty($tagqueue) ) {
				$tagqueue .= $tag;
				$tag = '';
			}
		}
		$newtext .= substr($text, 0, $i) . $tag;
		$text = substr($text, $i + $l);
	}

	// Clear Tag Queue
	$newtext .= $tagqueue;

	// Add Remaining text
	$newtext .= $text;

	// Empty Stack
	while( $x = array_pop($tagstack) )
		$newtext .= '</' . $x . '>'; // Add remaining tags to close

	// WP fix for the bug with HTML comments
	$newtext = str_replace("< !--","<!--",$newtext);
	$newtext = str_replace("<    !--","< !--",$newtext);

	return $newtext;
}

/**
 * Acts on text which is about to be edited.
 *
 * Unless $richedit is set, it is simply a holder for the 'format_to_edit'
 * filter. If $richedit is set true htmlspecialchars(), through esc_textarea(),
 * will be run on the content, converting special characters to HTML entities.
 *
 * @since 0.71
 *
 * @param string $content The text about to be edited.
 * @param bool $richedit Whether the $content should pass through htmlspecialchars(). Default false.
 * @return string The text after the filter (and possibly htmlspecialchars()) has been run.
 */
function format_to_edit( $content, $richedit = false ) {
	$content = apply_filters( 'format_to_edit', $content );
	if ( ! $richedit )
		$content = esc_textarea( $content );
	return $content;
}

/**
 * Holder for the 'format_to_post' filter.
 *
 * @since 0.71
 *
 * @param string $content The text to pass through the filter.
 * @return string Text returned from the 'format_to_post' filter.
 */
function format_to_post($content) {
	$content = apply_filters('format_to_post', $content);
	return $content;
}

/**
 * Add leading zeros when necessary.
 *
 * If you set the threshold to '4' and the number is '10', then you will get
 * back '0010'. If you set the number to '4' and the number is '5000', then you
 * will get back '5000'.
 *
 * Uses sprintf to append the amount of zeros based on the $threshold parameter
 * and the size of the number. If the number is large enough, then no zeros will
 * be appended.
 *
 * @since 0.71
 *
 * @param mixed $number Number to append zeros to if not greater than threshold.
 * @param int $threshold Digit places number needs to be to not have zeros added.
 * @return string Adds leading zeros to number if needed.
 */
function zeroise($number, $threshold) {
	return sprintf('%0'.$threshold.'s', $number);
}

/**
 * Adds backslashes before letters and before a number at the start of a string.
 *
 * @since 0.71
 *
 * @param string $string Value to which backslashes will be added.
 * @return string String with backslashes inserted.
 */
function backslashit($string) {
	$string = preg_replace('/^([0-9])/', '\\\\\\\\\1', $string);
	$string = preg_replace('/([a-z])/i', '\\\\\1', $string);
	return $string;
}

/**
 * Appends a trailing slash.
 *
 * Will remove trailing slash if it exists already before adding a trailing
 * slash. This prevents double slashing a string or path.
 *
 * The primary use of this is for paths and thus should be used for paths. It is
 * not restricted to paths and offers no specific path support.
 *
 * @since 1.2.0
 * @uses untrailingslashit() Unslashes string if it was slashed already.
 *
 * @param string $string What to add the trailing slash to.
 * @return string String with trailing slash added.
 */
function trailingslashit($string) {
	return untrailingslashit($string) . '/';
}

/**
 * Removes trailing slash if it exists.
 *
 * The primary use of this is for paths and thus should be used for paths. It is
 * not restricted to paths and offers no specific path support.
 *
 * @since 2.2.0
 *
 * @param string $string What to remove the trailing slash from.
 * @return string String without the trailing slash.
 */
function untrailingslashit($string) {
	return rtrim($string, '/');
}

/**
 * Adds slashes to escape strings.
 *
 * Slashes will first be removed if magic_quotes_gpc is set, see {@link
 * http://www.php.net/magic_quotes} for more details.
 *
 * @since 0.71
 *
 * @param string $gpc The string returned from HTTP request data.
 * @return string Returns a string escaped with slashes.
 */
function addslashes_gpc($gpc) {
	if ( get_magic_quotes_gpc() )
		$gpc = stripslashes($gpc);

	return esc_sql($gpc);
}

/**
 * Navigates through an array and removes slashes from the values.
 *
 * If an array is passed, the array_map() function causes a callback to pass the
 * value back to the function. The slashes from this value will removed.
 *
 * @since 2.0.0
 *
 * @param array|string $value The array or string to be stripped.
 * @return array|string Stripped array (or string in the callback).
 */
function stripslashes_deep($value) {
	if ( is_array($value) ) {
		$value = array_map('stripslashes_deep', $value);
	} elseif ( is_object($value) ) {
		$vars = get_object_vars( $value );
		foreach ($vars as $key=>$data) {
			$value->{$key} = stripslashes_deep( $data );
		}
	} else {
		$value = stripslashes($value);
	}

	return $value;
}

/**
 * Navigates through an array and encodes the values to be used in a URL.
 *
 * Uses a callback to pass the value of the array back to the function as a
 * string.
 *
 * @since 2.2.0
 *
 * @param array|string $value The array or string to be encoded.
 * @return array|string $value The encoded array (or string from the callback).
 */
function urlencode_deep($value) {
	$value = is_array($value) ? array_map('urlencode_deep', $value) : urlencode($value);
	return $value;
}

/**
 * Converts email addresses characters to HTML entities to block spam bots.
 *
 * @since 0.71
 *
 * @param string $emailaddy Email address.
 * @param int $mailto Optional. Range from 0 to 1. Used for encoding.
 * @return string Converted email address.
 */
function antispambot($emailaddy, $mailto=0) {
	$emailNOSPAMaddy = '';
	srand ((float) microtime() * 1000000);
	for ($i = 0; $i < strlen($emailaddy); $i = $i + 1) {
		$j = floor(rand(0, 1+$mailto));
		if ($j==0) {
			$emailNOSPAMaddy .= '&#'.ord(substr($emailaddy,$i,1)).';';
		} elseif ($j==1) {
			$emailNOSPAMaddy .= substr($emailaddy,$i,1);
		} elseif ($j==2) {
			$emailNOSPAMaddy .= '%'.zeroise(dechex(ord(substr($emailaddy, $i, 1))), 2);
		}
	}
	$emailNOSPAMaddy = str_replace('@','&#64;',$emailNOSPAMaddy);
	return $emailNOSPAMaddy;
}

/**
 * Callback to convert URI match to HTML A element.
 *
 * This function was backported from 2.5.0 to 2.3.2. Regex callback for {@link
 * make_clickable()}.
 *
 * @since 2.3.2
 * @access private
 *
 * @param array $matches Single Regex Match.
 * @return string HTML A element with URI address.
 */
function _make_url_clickable_cb($matches) {
	$url = $matches[2];
	$suffix = '';

	/** Include parentheses in the URL only if paired **/
	while ( substr_count( $url, '(' ) < substr_count( $url, ')' ) ) {
		$suffix = strrchr( $url, ')' ) . $suffix;
		$url = substr( $url, 0, strrpos( $url, ')' ) );
	}

	$url = esc_url($url);
	if ( empty($url) )
		return $matches[0];

	return $matches[1] . "<a href=\"$url\" rel=\"nofollow\">$url</a>" . $suffix;
}

/**
 * Callback to convert URL match to HTML A element.
 *
 * This function was backported from 2.5.0 to 2.3.2. Regex callback for {@link
 * make_clickable()}.
 *
 * @since 2.3.2
 * @access private
 *
 * @param array $matches Single Regex Match.
 * @return string HTML A element with URL address.
 */
function _make_web_ftp_clickable_cb($matches) {
	$ret = '';
	$dest = $matches[2];
	$dest = 'http://' . $dest;
	$dest = esc_url($dest);
	if ( empty($dest) )
		return $matches[0];

	// removed trailing [.,;:)] from URL
	if ( in_array( substr($dest, -1), array('.', ',', ';', ':', ')') ) === true ) {
		$ret = substr($dest, -1);
		$dest = substr($dest, 0, strlen($dest)-1);
	}
	return $matches[1] . "<a href=\"$dest\" rel=\"nofollow\">$dest</a>$ret";
}

/**
 * Callback to convert email address match to HTML A element.
 *
 * This function was backported from 2.5.0 to 2.3.2. Regex callback for {@link
 * make_clickable()}.
 *
 * @since 2.3.2
 * @access private
 *
 * @param array $matches Single Regex Match.
 * @return string HTML A element with email address.
 */
function _make_email_clickable_cb($matches) {
	$email = $matches[2] . '@' . $matches[3];
	return $matches[1] . "<a href=\"mailto:$email\">$email</a>";
}

/**
 * Convert plaintext URI to HTML links.
 *
 * Converts URI, www and ftp, and email addresses. Finishes by fixing links
 * within links.
 *
 * @since 0.71
 *
 * @param string $ret Content to convert URIs.
 * @return string Content with converted URIs.
 */
function make_clickable($ret) {
	$ret = ' ' . $ret;
	// in testing, using arrays here was found to be faster
	$save = @ini_set('pcre.recursion_limit', 10000);
	$retval = preg_replace_callback('#(?<!=[\'"])(?<=[*\')+.,;:!&$\s>])(\()?([\w]+?://(?:[\w\\x80-\\xff\#%~/?@\[\]-]{1,2000}|[\'*(+.,;:!=&$](?![\b\)]|(\))?([\s]|$))|(?(1)\)(?![\s<.,;:]|$)|\)))+)#is', '_make_url_clickable_cb', $ret);
	if (null !== $retval )
		$ret = $retval;
	@ini_set('pcre.recursion_limit', $save);
	$ret = preg_replace_callback('#([\s>])((www|ftp)\.[\w\\x80-\\xff\#$%&~/.\-;:=,?@\[\]+]+)#is', '_make_web_ftp_clickable_cb', $ret);
	$ret = preg_replace_callback('#([\s>])([.0-9a-z_+-]+)@(([0-9a-z-]+\.)+[0-9a-z]{2,})#i', '_make_email_clickable_cb', $ret);
	// this one is not in an array because we need it to run last, for cleanup of accidental links within links
	$ret = preg_replace("#(<a( [^>]+?>|>))<a [^>]+?>([^>]+?)</a></a>#i", "$1$3</a>", $ret);
	$ret = trim($ret);
	return $ret;
}

/**
 * Adds rel nofollow string to all HTML A elements in content.
 *
 * @since 1.5.0
 *
 * @param string $text Content that may contain HTML A elements.
 * @return string Converted content.
 */
function wp_rel_nofollow( $text ) {
	// This is a pre save filter, so text is already escaped.
	$text = stripslashes($text);
	$text = preg_replace_callback('|<a (.+?)>|i', 'wp_rel_nofollow_callback', $text);
	$text = esc_sql($text);
	return $text;
}

/**
 * Callback to used to add rel=nofollow string to HTML A element.
 *
 * Will remove already existing rel="nofollow" and rel='nofollow' from the
 * string to prevent from invalidating (X)HTML.
 *
 * @since 2.3.0
 *
 * @param array $matches Single Match
 * @return string HTML A Element with rel nofollow.
 */
function wp_rel_nofollow_callback( $matches ) {
	$text = $matches[1];
	$text = str_replace(array(' rel="nofollow"', " rel='nofollow'"), '', $text);
	return "<a $text rel=\"nofollow\">";
}

/**
 * Convert one smiley code to the icon graphic file equivalent.
 *
 * Looks up one smiley code in the $wpsmiliest…