Newsgroups: php.internals
Path: news.php.net
Xref: news.php.net php.internals:28202
Mailing-List: contact internals-help@lists.php.net; run by ezmlm
Received-SPF: pass (pb1.pair.com: domain kromann.info designates 64.186.239.125 as permitted sender)
To: Andy Wharmby <andy.wharmby@googlemail.com>
Cc: Wez Furlong <kingwez@gmail.com>,
	PHP internals list <internals@lists.php.net>
Message-ID: <11728540521160000@9866357972520000.9866341568840000>
MIME-Version: 1.0
Reply-To: "Frank M. Kromann" <frank@kromann.info>
Date: Fri, 02 Mar 2007 08:47:32 -0800
Content-Type: text/plain;
	charset="us-ascii"
Content-Transfer-Encoding: 7bit
Subject: Re: COM extension defects: Patch for defect 35872
From: frank@kromann.info ("Frank M. Kromann")

Hi ANdy,

Looks good to me. Nice and clean.

- Frank

> Hi Internals,
>       Below are details of a suggested patch for COM extension defect 
> 35872 (http://bugs.php.net/bug.php?id=35872) for review/approval.
> All comments welcome; good or bad.
> 
> Regards
>    Andy
> 
> Andy Wharmby
> IBM United Kingdom Limited
> Winchester, England SO21 2JN
> E-mail: andy_wharmby@uk.ibm.com
> 
> Using supplied testcase the backtrace is as follows:
> 
>     php6ts_debug.dll!zend_object_store_get_object(_zval_struct * 
> zobject=0x009c19e8, void * * * tsrm_ls=0x009659a8)  Line 263 + 0x1b   
C
>      php6ts_debug.dll!zend_objects_get_address(_zval_struct * 
> zobject=0x009c19e8, void * * * tsrm_ls=0x009659a8)  Line 144 + 0xd    C
>      php6ts_debug.dll!zend_std_object_get_class(_zval_struct * 
> object=0x009c19e8, void * * * tsrm_ls=0x009659a8)  Line 1074 + 0xd    C
>      php6ts_debug.dll!zend_get_class_entry(_zval_struct * 
> zobject=0x009c19e8, void * * * tsrm_ls=0x009659a8)  Line 239 + 0x13   
C
>      php6ts_debug.dll!disp_destructor(php_dispatchex * disp=0x00194460) 

> Line 562 + 0x10    C
>      php6ts_debug.dll!dispatch_dtor(_zend_rsrc_list_entry * 
> rsrc=0x009c3230, void * * * tsrm_ls=0x009659a8)  Line 60 + 0x9    C
>      php6ts_debug.dll!list_entry_destructor(void * ptr=0x009c3230)  Line

> 184 + 0x10    C
>      php6ts_debug.dll!zend_hash_apply_deleter(_hashtable * 
> ht=0x00968290, bucket * p=0x009c31d8)  Line 836 + 0xf    C
>      php6ts_debug.dll!zend_hash_graceful_reverse_destroy(_hashtable * 
> ht=0x00968290)  Line 871 + 0xd    C
>      php6ts_debug.dll!zend_destroy_rsrc_list(_hashtable * ht=0x00968290,

> void * * * tsrm_ls=0x009659a8)  Line 240 + 0x9    C
>      php6ts_debug.dll!zend_deactivate(void * * * tsrm_ls=0x009659a8)  
> Line 1358 + 0x1e    C
>      php6ts_debug.dll!php_request_shutdown(void * dummy=0x00000000)  
> Line 1429 + 0x9    C
>      php.exe!main(int argc=0x00000003, char * * argv=0x009658f8)  Line 
> 1306 + 0xa    C
>      php.exe!mainCRTStartup()  Line 398 + 0x11    C
> 
> We fail in zend_object_store_get_object() after the objects store has 
> been destroyed earlier in request shutdown by
zend_objects_store_destroy().
> Which is very similar to defect 34617 
> (http://bugs.php.net/bug.php?id=34617).
> 
> The reference to the object store is caused by the trace()  call in 
> disp_destructor(). This call to trace() should probably be a NOOP in a 
> non-debug build
>  but we still need to fix reported problem so DEBUG builds don't hit the

> problem. I will raise a separate defect to disable the trace calls in 
> non-DEBUG builds.
> 
> I have resolved the problem reported under defect 35872 by defining a 
> new boolean flag "rshutdown_started" in COMG which is set to false by 
> COM RINIT
> routine and true by  the COM RSHUTDOWN routine. This allows the COM code

> to avoid reference to the object store if invoked during request
shutdown.
> The trace calls themselves have been modified to add the object address

> to allow entries referring to the same object to be correlated  even if

> the object name is not
> available.
> 
> Fixing code in disp_destructor revealed a similar issue in FETCH_DISP 
> macro which is fixed in a same  way.
> 
> The full patch; built against CVS HEAD is attached. 
> 
>