Home Original page

preg_split() swallows part of the string

Bug #42945 preg_split() swallows part of the string
Submitted: 2007-10-12 12:04 UTC Modified: 2008-01-13 14:44 UTC
Votes:2
Avg. Score:4.0 ± 1.0
Reproduced:2 of 2 (100.0%)
Same Version:1 (50.0%)
Same OS:1 (50.0%)
From: Arne dot Heizmann at csr dot com Assigned:
Status: Closed Package: PCRE related
PHP Version: 5CVS-2007-10-22 OS: *
Private report: No CVE-ID: None

 [2007-10-12 12:04 UTC] Arne dot Heizmann at csr dot com

Description:
------------
The following example code shows how preg_split() - when used with PREG_SPLIT_NO_EMPTY - omits pieces which aren't empty. The returned array SHOULD contain ALL of the characters from the original string minus the characters that match the separator. In my example, the separator is a zero-width match.

I notice that this problem was reported as Bug #15413 before and marked "Bogus". My example shows that the bug is real.

Reproduce code:
---------------
<?
    header ('Content-type: text/plain');
    var_export (preg_split ('/\b/', 'a\'', -1, PREG_SPLIT_NO_EMPTY));
?>


Expected result:
----------------
array (
  0 => 'a',
  1 => '\'',
)

Actual result:
--------------
array (
  0 => 'a',
)

Patches

Pull Requests

History

AllCommentsChangesGit/SVN commitsRelated reports

 [2007-10-22 08:52 UTC] jani@php.net

Verified using latest CVS snapshot.

 [2008-01-12 02:16 UTC] felipe@php.net

I tested in PHP 5.3


Index: php_pcre.c
===================================================================
RCS file: /repository/php-src/ext/pcre/php_pcre.c,v
retrieving revision 1.168.2.9.2.21.2.8
diff -u -r1.168.2.9.2.21.2.8 php_pcre.c
--- php_pcre.c  31 Dec 2007 07:17:11 -0000      1.168.2.9.2.21.2.8
+++ php_pcre.c  12 Jan 2008 02:14:13 -0000
@@ -1562,7 +1562,7 @@
        }
 
 
-       if (!no_empty || start_offset != subject_len)
+       if (!no_empty || last_match[0] != '\0')
        {
                if (offset_capture) {
                        /* Add the last (match, offset) pair to the return value */

 [2008-01-13 14:44 UTC] nlopess@php.net

This bug has been fixed in CVS.

Snapshots of the sources are packaged every three hours; this change
will be in the next snapshot. You can grab the snapshot at
http://snaps.php.net/.
 
Thank you for the report, and for helping us make PHP better.