From:
Operating system: AIX64
PHP version: 5.3.2
Package: Strings related
Bug Type: Bug
Bug description:unpack('I', $x) on 64 bit big endian unreliable
Description:
------------
Testing unpack 'I' format on a 64bit big-endian architecture.
The result depends on the sign bit in the *next* integer in the packed
buffer
or a out of buffer byte if it is not that long.
A patch which resolves this is below.
I think the code ends up producing identical results for the I and i
format which may be the most desirable thing but the code looks like it
was
intended to behave differently. Maybe it can be simplified.
Similar to bug #40894 but a different format (I).
patch:
*** pack.c Thu Mar 11 15:05:11 2010
--- pack.c.orig Thu Mar 11 15:03:20 2010
***************
*** 752,758 ****
if (type == 'i') {
issigned =
input[inputpos + (machine_little_endian ? (sizeof(int) - 1) : 0)] & 0x80;
! } else if (sizeof(long) > 4
&& input[inputpos + (machine_little_endian ? (sizeof(int) - 1) : 0)] & 0x80
== 0x80) {
v = ~INT_MAX;
}
--- 752,758 ----
if (type == 'i') {
issigned =
input[inputpos + (machine_little_endian ? (sizeof(int) - 1) : 0)] & 0x80;
! } else if (sizeof(long) > 4
&& (input[inputpos + machine_endian_long_map[3]] & 0x80) == 0x80) {
v = ~INT_MAX;
}
Test script:
---------------
<?php
echo PHP_INT_MAX."\n";
print_r(unpack('I', pack('I', -10000) . pack('I', 10000)));
print_r(unpack('I', pack('I', -10000) . pack('I', -10000)));
?>
Expected result:
----------------
9223372036854775807
Array
(
[1] => -10000
)
Array
(
[1] => -10000
)
Actual result:
--------------
9223372036854775807
Array
(
[1] => 4294957296
)
Array
(
[1] => -10000
)
--
Edit bug report at http://bugs.php.net/bug.php?id=51275&edit=1
--
Try a snapshot (PHP 5.2):
http://bugs.php.net/fix.php?id=51275&r=trysnapshot52
Try a snapshot (PHP 5.3):
http://bugs.php.net/fix.php?id=51275&r=trysnapshot53
Try a snapshot (PHP 6.0):
http://bugs.php.net/fix.php?id=51275&r=trysnapshot60
Fixed in SVN:
http://bugs.php.net/fix.php?id=51275&r=fixed
Fixed in SVN and need be documented:
http://bugs.php.net/fix.php?id=51275&r=needdocs
Fixed in release:
http://bugs.php.net/fix.php?id=51275&r=alreadyfixed
Need backtrace:
http://bugs.php.net/fix.php?id=51275&r=needtrace
Need Reproduce Script:
http://bugs.php.net/fix.php?id=51275&r=needscript
Try newer version:
http://bugs.php.net/fix.php?id=51275&r=oldversion
Not developer issue:
http://bugs.php.net/fix.php?id=51275&r=support
Expected behavior:
http://bugs.php.net/fix.php?id=51275&r=notwrong
Not enough info:
http://bugs.php.net/fix.php?id=51275&r=notenoughinfo
Submitted twice:
http://bugs.php.net/fix.php?id=51275&r=submittedtwice
register_globals:
http://bugs.php.net/fix.php?id=51275&r=globals
PHP 4 support discontinued: http://bugs.php.net/fix.php?id=51275&r=php4
Daylight Savings: http://bugs.php.net/fix.php?id=51275&r=dst
IIS Stability:
http://bugs.php.net/fix.php?id=51275&r=isapi
Install GNU Sed:
http://bugs.php.net/fix.php?id=51275&r=gnused
Floating point limitations:
http://bugs.php.net/fix.php?id=51275&r=float
No Zend Extensions:
http://bugs.php.net/fix.php?id=51275&r=nozend
MySQL Configuration Error:
http://bugs.php.net/fix.php?id=51275&r=mysqlcfg
