note 73070 added to function.preg-replace

A bug exists in the REGEX engine, preventing preg_replace from outputting NULL characters. (They end up as a literal '\0' instead.) As a workaround, you can use str_replace() to handle NULLs. Here are some examples of 4 functions for URL validation and HTML encoding using preg_replace(), with the str_replace() workaround, making them binary-safe and able to handle NULLs: <?php /* **BINARY-SAFE** URL-validator and various HTML-encoders by Justin Frim Feel free to use in your own code. */ function url_validate($uncertainURL){ //URL validator return preg_replace('/([\\x01-\\x20"<>`\\x7F-\\xFF])/e', "'%'.sprintf('%02X',ord('\\1'))", str_replace("\0",'%00',$uncertainURL)); } function ASCII_htmlspecialchars($literaldata){ //HTML encoder //Only outputs printable ASCII. return preg_replace('/([\\x01-\\x19\\x7F-\\xFF])/e', "'&#'.ord('\\1').';'", str_replace("\0",'&#0;',htmlspecialchars($literaldata)); } function ASCII_CRLF_htmlspecialchars($literaldata){ //HTML encoder //Only outputs printable ASCII, CRs, and LFs. return preg_replace('/([\\x01-\\x09\\x0B\\x0C\\x0E-\\x1F \\x7F-\\xFF])/e', "'&#'.ord('\\1').';'", str_replace("\0",'&#0;',htmlspecialchars($literaldata))); } function ASCII_nl2br_htmlspecialchars($literaldata){ //HTML encoder w. newline translation //Only outputs printable ASCII, CRs, and LFs. return nl2br(preg_replace( '/([\\x01-\\x09\\x0B\\x0C\\x0E-\\x1F \\x7F-\\xFF])/e', "'&#'.ord('\\1').';'", str_replace("\0",'&#0;',htmlspecialchars($literaldata)))); } ?> Typical uses: url_validate(): Ensure a string (assumed to be a URL) is URL-compliant. Only encodes any unsafe characters found in the string. (Reserved characters are left as-is.) ASCII_htmlspecialchars(): Replacement for htmlspecialchars(), ensuring all control characters and high 8-bit characters are represented with printable ASCII HTML codes. Ideal for outputting text or binary data as HTML tag parameters. ASCII_CRLF_htmlspecialchars(): Same as above, but allowing CRs and LFs to pass through unencoded. Use for outputting non-display text to an HTML document where newlines must be retained in the HTML source, or display text if newlines are to appear simply as spaces. ASCII_nl2br_htmlspecialchars(): Same as above, but adding <br \> before any CRs, LFs, CRLFs, and LFCRs. Use for outputting display text to an HTML document, keeping the appearance of newlines intact. (Note that it can NOT be used for tag parameters!) ---- Server IP: 216.235.15.211 Probable Submitter: 64.7.136.101 ---- Manual Page -- http://www.php.net/manual/en/function.preg-replace.php Edit -- https://master.php.net/note/edit/73070 Del: integrated -- https://master.php.net/note/delete/73070/integrated Del: useless -- https://master.php.net/note/delete/73070/useless Del: bad code -- https://master.php.net/note/delete/73070/bad+code Del: spam -- https://master.php.net/note/delete/73070/spam Del: non-english -- https://master.php.net/note/delete/73070/non-english Del: in docs -- https://master.php.net/note/delete/73070/in+docs Del: other reasons-- https://master.php.net/note/delete/73070 Reject -- https://master.php.net/note/reject/73070 Search -- https://master.php.net/manage/user-notes.php