#28494 [Opn->Bgs]: Using utf8_decode with ereg breaks ereg

ID: 28494 Updated by: moriyoshi@php.net Reported By: david at collectfair dot co dot uk -Status: Open +Status: Bogus -Bug Type: *Regular Expressions +Bug Type: *Languages/Translation Operating System: Linux PHP Version: 4.3.6 New Comment: 1. You cannot use utf8_decode() for generic UTF-8 decoding. It was designed specifically to use with ISO -8859-1 characters. Consider using mb_convert_encoding() or iconv() instead. 2. ereg() neither supports UTF-8. Try using preg_match(). Previous Comments: ------------------------------------------------------------------------ [2004-05-23 14:40:08] david at collectfair dot co dot uk Further testing shows that failure only occurs when the %f0 is at the GET string Changing to this Perl based regular expression removes the problem completely. preg_match('/^\d{1,8}$/', utf8_decode($_GET['tt'])); ------------------------------------------------------------------------ [2004-05-23 01:59:20] david at collectfair dot co dot uk Description: ------------ ereg wrongly indicates that a GET string contains only integers if the string is first processed using utf8_decode. Example: The regular expression should return true only if the variable 'tt' in the GET string contains between 1 and 8 number characters. This behaves correctly: ereg('^[0-9]{1,8}$',$_GET['tt'])) This behaves wrongly: ereg('^[0-9]{1,8}$',utf8_decode($_GET['tt']))) --------------------------------------------------- PHP Configure line - './configure' '--with-apxs2=/usr/local/apache/bin/apxs' '--with-mysql=/usr/local/mysql/' '--with-mysql-sock=/tmp/mysql.sock' '--enable-exif' '--with-gd' '--with-jpeg-dir=/usr/lib' '--with-png-dir=/usr/lib' '--with-zlib-dir=/usr/lib' '--with-xpm-dir=/usr/lib' '--with-freetype-dir=/usr/lib' '--with-t1lib=/usr/lib' '--with-freetype-dir=/usr/lib' '--disable-debug' '--with-config-file-path=/etc/httpd' '--with-openssl=/usr/local/ssl' '--enable-memory-limit' ---------------------------------------------------- Apache 2.0.49 core mod_access mod_auth mod_include mod_log_config mod_env mod_headers mod_setenvif mod_ssl prefork http_core mod_mime mod_status mod_autoindex mod_asis mod_cgi mod_negotiation mod_dir mod_imap mod_actions mod_alias mod_so mod_expires mod_rewrite mod_deflate mod_logio sapi_apache2 mod_security Reproduce code: --------------- Call this script with the following line in the browser: http://localhost/test.php?tt=119%f0 <?php if(isset($_GET['tt']) && eregi('^[0-9]{1,8}$',utf8_decode($_GET['tt']))){ //Should only get here if 'tt' is an integer echo 'Integer'; }else{ echo 'Not an integer'; } ?> Expected result: ---------------- The script should return "Not an integer" in the browser. Actual result: -------------- The script returns "Integer" in the browser, even though the GET string contains other characters. ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=28494&edit=1