ID: 39344
Updated by: [EMAIL PROTECTED]
Reported By: wharmby at uk dot ibm dot com
-Status: Open
+Status: Assigned
Bug Type: Scripting Engine problem
Operating System: Windows XP
PHP Version: 5CVS-2006-11-02 (snap)
-Assigned To:
+Assigned To: dmitry
Previous Comments:
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[2006-11-03 09:03:38] wharmby at uk dot ibm dot com
Correcting version; behaviour was observed in V5 not V4
------------------------------------------------------------------------
[2006-11-02 11:10:56] wharmby at uk dot ibm dot com
Description:
------------
Unnecessary calls to OnModify callback routine for an
extension INI directives in ZTS enabled builds.
Please note the problem reported here only applies to ZTS
enabled builds.
I have tried the supplied testcase on the latest snap-shot
build for Windows (Nov 2, 2006 09:30 GMT)and the problem
persists. phpinfo() shows "PHP Version => 5.2.1-dev".
Problem also persists in latest checked in version of file
in CVS.
If I define a OnMOdify callback routine for an extension INI
directive the routine is called multiple times during
startup even though the directive is not being continually
modified. I expected one call as a result of modification to
the directive in php.ini but instead I got 3 calls.
I spotted this behaviour reviewing the engine code whilst
reading Sara Golemon's book "Extending and Embedding PHP"
and include a slightly modified version of sample code
from her book to illustrate the unnecessary calls.
The first problem is that in a ZTS enabled build
zend_ini_refresh_caches() is called twice for each new
thread. The method zend_new_thread_end_handler() calls it
directly as follows:
static void zend_new_thread_end_handler(THREAD_T thread_id TSRMLS_DC)
{
zend_copy_ini_directives(TSRMLS_C);
zend_ini_refresh_caches(ZEND_INI_STAGE_STARTUP TSRMLS_CC);
}
However, zend_copy_ini_directives() itself also calls
zend_ini_refresh_caches() so we end up calling any OnModifty callback
routines twice for each new thread.
I believe that:
(1) the call in zend_copy_ini_directives() can safely be
removed, and
(2) the call in zend_new_thread_end_handler() should
really be conditional on the success of the copy
operation, otherwise we could attempt to iterate
over a non-existent hash and die.
This will reduce the number of calls to 2 on ZTS emabled builds but any
OnModifycallback routine will still be called twice on the startup
thread in ZTS enabled builds; once by zend_register_ini_entries()
during MINIT processing when an extension registers its INI directives
and again on ZTS
builds during zend_post_startup() processing, i.e
zend_post_startup() -> zend_new_thread_end_handler() ->
zend_ini_refresh_caches()
Whilst the call to the OnModify callback routine from
zend_register_ini_entries() is required for non-ZTS builds
to work correctly I can see no need for a call from
zend_ini_refresh_caches() during zend_post-startup
processing. I believe this can easily be resolved by
modifying zend_post_startup() to call
zend_copy_ini_directives()
instead of
zend_new_thread_end_handler()
My patch for zend.c is here: http://pastebin.ca/234196
and for zend_ini.c here: http://pastebin.ca/234200
Reproduce code:
---------------
Reproduce code is here: http://pastebin.ca/234201
I tested by adding the following to php.ini:
sample4.greeting="Hello Andy"
or via command line as:
-dsample4.greeting="Hello Andy"
Expected result:
----------------
When running using CLI on Windows, i.e a ZTS enabled build, I
expected to see 1 call to my extensions "OnModify" callback
routine for each thread attached; so in this simple case I expected to
see just the 1 call as follows:
>> sample 4: thread 0xfbc minit
sample 4: thread 0xfbc greeting modified..new value is Hello Andy
<< sample 4: thread 0xfbc minit
Hello Andy
Actual result:
--------------
The OnModify call back routine is in fact called 3 times; once
during MINIT processing and twice further. These last 2 are during the
call to zend_new_thread-end_handler().
>> sample 4: thread 0x16f8 minit
sample 4: thread 0x16f8 greeting modified..new value is Hello Andy
<< sample 4: thread 0x16f8 minit
sample 4: thread 0x16f8 greeting modified..new value is Hello Andy
sample 4: thread 0x16f8 greeting modified..new value is Hello Andy
Hello Andy
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Edit this bug report at http://bugs.php.net/?id=39344&edit=1
