#47171 [NEW]: Incorrect tell values when trying to seek beyond file range

From: d_kelsey at uk dot ibm dot com Operating system: Windows PHP version: 5.2.8 PHP Bug Type: Zlib Related Bug description: Incorrect tell values when trying to seek beyond file range Description: ------------ When attempting to seek a zlib stream outside the range of the file eg -50 or 2000 (and the uncompressed length is < 2000) in either read or write mode, after the seek operation a gztell call returns false. In most cases the file pointer doesn't move so I can perform further reads or writes but the tell value returns now an invalid value. If a attempt to seek forward in read mode beyond the end of the uncompressed stream it looks like the file pointer remains at the end of the stream as a subsequent read returns nothing. In all cases I would expect - seek & gzseek to return -1 - the file pointer to remain where it was - the tell to return the same value as before the seek In other words the operation fails and nothing changes. Reproduce code: --------------- <?php $f = dirname(__FILE__)."/004.txt.gz"; $h = gzopen($f, 'r'); echo "move to the 40th byte\n"; echo "seek="; var_dump(gzseek( $h, 40 ) ); echo "tell=".gztell($h)."\n"; echo "try to move beyond the file\n"; echo "seek="; var_dump(gzseek( $h, 1000 ) ); echo "tell="; var_dump(gztell($h)); var_dump(gzread($h, 10)); echo "tell="; var_dump(gztell($h)); echo "\nrewinding and try to move to before the start\n"; gzrewind($h); echo "tell=".gztell($h)."\n"; echo "gzseek="; var_dump(gzseek( $h, -5 ) ); echo "tell="; var_dump(gztell($h)); var_dump(gzread($h, 10)); echo "tell="; var_dump(gztell($h)); gzclose($h); ?> Expected result: ---------------- move to the 40th byte seek=int(0) tell=40 try to move beyond the file seek=int(-1) tell=int(40) string(10) "iny flying" tell=int(50) rewinding and try to move to before the start tell=0 gzseek=int(-1) tell=int(0) string(10) "When you'r" tell=int(10) Actual result: -------------- move to the 40th byte seek=int(0) tell=40 try to move beyond the file seek=int(-1) tell=bool(false) string(0) "" tell=bool(false) rewinding and try to move to before the start tell=0 gzseek=int(-1) tell=bool(false) string(10) "When you'r" tell=int(9) -- Edit bug report at http://bugs.php.net/?id=47171&edit=1 -- Try a CVS snapshot (PHP 5.2): http://bugs.php.net/fix.php?id=47171&r=trysnapshot52 Try a CVS snapshot (PHP 5.3): http://bugs.php.net/fix.php?id=47171&r=trysnapshot53 Try a CVS snapshot (PHP 6.0): http://bugs.php.net/fix.php?id=47171&r=trysnapshot60 Fixed in CVS: http://bugs.php.net/fix.php?id=47171&r=fixedcvs Fixed in CVS and need be documented: http://bugs.php.net/fix.php?id=47171&r=needdocs Fixed in release: http://bugs.php.net/fix.php?id=47171&r=alreadyfixed Need backtrace: http://bugs.php.net/fix.php?id=47171&r=needtrace Need Reproduce Script: http://bugs.php.net/fix.php?id=47171&r=needscript Try newer version: http://bugs.php.net/fix.php?id=47171&r=oldversion Not developer issue: http://bugs.php.net/fix.php?id=47171&r=support Expected behavior: http://bugs.php.net/fix.php?id=47171&r=notwrong Not enough info: http://bugs.php.net/fix.php?id=47171&r=notenoughinfo Submitted twice: http://bugs.php.net/fix.php?id=47171&r=submittedtwice register_globals: http://bugs.php.net/fix.php?id=47171&r=globals PHP 4 support discontinued: http://bugs.php.net/fix.php?id=47171&r=php4 Daylight Savings: http://bugs.php.net/fix.php?id=47171&r=dst IIS Stability: http://bugs.php.net/fix.php?id=47171&r=isapi Install GNU Sed: http://bugs.php.net/fix.php?id=47171&r=gnused Floating point limitations: http://bugs.php.net/fix.php?id=47171&r=float No Zend Extensions: http://bugs.php.net/fix.php?id=47171&r=nozend MySQL Configuration Error: http://bugs.php.net/fix.php?id=47171&r=mysqlcfg