Bug #66777 [NEW]: strftime returns empty string when input fmt string exceeds 1024

From: csyangchen at hotmail dot com Operating system: PHP version: Irrelevant Package: Date/time related Bug Type: Bug Bug description:strftime returns empty string when input fmt string exceeds 1024 Description: ------------ strftime returns empty string when input fmt string exceeds 1024 due to the undocumented code logic in 'ext/date/php_date.c' php_strftime ... int max_reallocs = 5; size_t buf_len = 256, real_len; ... buf = (char *) emalloc(buf_len); while ((real_len=strftime(buf, buf_len, format, &ta))==buf_len || real_len==0) { buf_len *= 2; buf = (char *) erealloc(buf, buf_len); if (!--max_reallocs) { break; } } ... the logic to abort reallocation after 5 times is undocumented. thus we can have at most 256 * 5 = 1024 size string. Test script: --------------- echo strftime(str_repeat('x', 1024)); Expected result: ---------------- should output 1024 occurrences of 'x' Actual result: -------------- empty string -- Edit bug report at https://bugs.php.net/bug.php?id=66777&edit=1 -- Try a snapshot (PHP 5.4): https://bugs.php.net/fix.php?id=66777&r=trysnapshot54 Try a snapshot (PHP 5.5): https://bugs.php.net/fix.php?id=66777&r=trysnapshot55 Try a snapshot (trunk): https://bugs.php.net/fix.php?id=66777&r=trysnapshottrunk Fixed in SVN: https://bugs.php.net/fix.php?id=66777&r=fixed Fixed in release: https://bugs.php.net/fix.php?id=66777&r=alreadyfixed Need backtrace: https://bugs.php.net/fix.php?id=66777&r=needtrace Need Reproduce Script: https://bugs.php.net/fix.php?id=66777&r=needscript Try newer version: https://bugs.php.net/fix.php?id=66777&r=oldversion Not developer issue: https://bugs.php.net/fix.php?id=66777&r=support Expected behavior: https://bugs.php.net/fix.php?id=66777&r=notwrong Not enough info: https://bugs.php.net/fix.php?id=66777&r=notenoughinfo Submitted twice: https://bugs.php.net/fix.php?id=66777&r=submittedtwice register_globals: https://bugs.php.net/fix.php?id=66777&r=globals PHP 4 support discontinued: https://bugs.php.net/fix.php?id=66777&r=php4 Daylight Savings: https://bugs.php.net/fix.php?id=66777&r=dst IIS Stability: https://bugs.php.net/fix.php?id=66777&r=isapi Install GNU Sed: https://bugs.php.net/fix.php?id=66777&r=gnused Floating point limitations: https://bugs.php.net/fix.php?id=66777&r=float No Zend Extensions: https://bugs.php.net/fix.php?id=66777&r=nozend MySQL Configuration Error: https://bugs.php.net/fix.php?id=66777&r=mysqlcfg