From: axelluttgens at swing dot be
Operating system: Mac OS 10.4.7
PHP version: 4.4.2
PHP Bug Type: PCNTL related
Bug description: Incorrect return address after the execution of a signal
handler?
Description:
------------
It seems there is a problem with the construction of the return address to
be used after an interrupt handler.
Now, I'm not sure whether the problem is a general one, or more precisely
located in the socket_xxx() family of functions.
I used the socket_select() function for building the example, as I needed
a function whose execution is liable to be suspended until the occurence
of an interrupt.
But the "workaround" described hereafter anyway seems to reveal some
misbehavior.
Reproduce code:
---------------
Create an executable file, say "sigtest.php", with following contents:
#!/usr/local/bin/php
<?php
declare(ticks = 1);
$gotINT = FALSE;
function SaveINT()
{
$GLOBALS['gotINT'] = TRUE;
echo "Received SIGINT\n";
}
function HandleINT()
{
echo "Handling SIGINT\n";
}
function PollSigs()
{
if ($GLOBALS['gotINT'])
HandleINT();
}
pcntl_signal(SIGINT, 'SaveINT');
$endpoint = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
socket_bind($endpoint, '127.0.0.1', 12345);
socket_listen($endpoint, 10);
while (!socket_select($r = array($endpoint), $w = NULL, $e = NULL, NULL))
if (($err = socket_last_error()) === SOCKET_EINTR)
{
# $err = $err;
PollSigs();
}
else
{
echo "socket_select() failed with $err\n";
exit(1);
}
?>
Expected result:
----------------
During execution of above file on the terminal, a break (^C) should result
in:
1. the capture of SIGINT, and thus the execution of SaveINT(),
2. the continuation of execution after socket_select(), and thus the
execution of HandleINT() consecutively to the call of PollSigs().
Actual result:
--------------
[1] With above code, launching the executable yields:
$ /Volumes/Data/Sources/sigtest.php
^C
Warning: socket_select() unable to select [4]: Interrupted system call in
/Volumes/Data/Sources/sigtest.php on line 31
Received SIGINT
^C
Warning: socket_select() unable to select [4]: Interrupted system call in
/Volumes/Data/Sources/sigtest.php on line 31
Handling SIGINT
Received SIGINT
[2] Now, uncomment the
# $err = $err;
line in the source and launch the executable again:
$ /Volumes/Data/Sources/sigtest.php
^C
Warning: socket_select() unable to select [4]: Interrupted system call in
/Volumes/Data/Sources/sigtest.php on line 31
Received SIGINT
Handling SIGINT
^C
Warning: socket_select() unable to select [4]: Interrupted system call in
/Volumes/Data/Sources/sigtest.php on line 31
Received SIGINT
Handling SIGINT
The dummy instruction (ie, $err = $err;) thus allows to restore exepected
behavior.
--
Edit bug report at http://bugs.php.net/?id=38273&edit=1
--
Try a CVS snapshot (PHP 4.4):
http://bugs.php.net/fix.php?id=38273&r=trysnapshot44
Try a CVS snapshot (PHP 5.2):
http://bugs.php.net/fix.php?id=38273&r=trysnapshot52
Try a CVS snapshot (PHP 6.0):
http://bugs.php.net/fix.php?id=38273&r=trysnapshot60
Fixed in CVS: http://bugs.php.net/fix.php?id=38273&r=fixedcvs
Fixed in release:
http://bugs.php.net/fix.php?id=38273&r=alreadyfixed
Need backtrace: http://bugs.php.net/fix.php?id=38273&r=needtrace
Need Reproduce Script: http://bugs.php.net/fix.php?id=38273&r=needscript
Try newer version: http://bugs.php.net/fix.php?id=38273&r=oldversion
Not developer issue: http://bugs.php.net/fix.php?id=38273&r=support
Expected behavior: http://bugs.php.net/fix.php?id=38273&r=notwrong
Not enough info:
http://bugs.php.net/fix.php?id=38273&r=notenoughinfo
Submitted twice:
http://bugs.php.net/fix.php?id=38273&r=submittedtwice
register_globals: http://bugs.php.net/fix.php?id=38273&r=globals
PHP 3 support discontinued: http://bugs.php.net/fix.php?id=38273&r=php3
Daylight Savings: http://bugs.php.net/fix.php?id=38273&r=dst
IIS Stability: http://bugs.php.net/fix.php?id=38273&r=isapi
Install GNU Sed: http://bugs.php.net/fix.php?id=38273&r=gnused
Floating point limitations: http://bugs.php.net/fix.php?id=38273&r=float
No Zend Extensions: http://bugs.php.net/fix.php?id=38273&r=nozend
MySQL Configuration Error: http://bugs.php.net/fix.php?id=38273&r=mysqlcfg
