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Date: Fri, 10 Mar 2006 07:58:48 -0800
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To: "Brian J. France" <list@firehawksystems.com>
CC: Andi Gutmans <andi@zend.com>, internals@lists.php.net
References: <0FF5C589-6436-45E0-8626-F0B9944046ED@firehawksystems.com> <7.0.1.0.2.20060309222503.08a04930@zend.com> <44111D29.8030407@lerdorf.com> <44112364.7070607@lerdorf.com> <E7EAE063-8228-4F43-9669-383BFB2253B5@firehawksystems.com>
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Subject: Re: [PHP-DEV] primary file realpath change
From: rasmus@lerdorf.com (Rasmus Lerdorf)

After poking this a bit more, it looks like this whole block of code in 
main.c is redundant.  Here is the story:

We start our journey on a dark and stormy night in June 2002 with this 
bug:  http://bugs.php.net/17720

This led to this fix: 
http://cvs.php.net/viewcvs.cgi/php-src/main/main.c?r1=1.461&r2=1.462
which had this commit message:
Main script should not be parsed when (include|require)_once()'ed, #17720
# Derick, MFH?

Now, at the time this was the correct fix.  However, fast forward to 
March 2005 and we have a patch from Stas to zend_execute_scripts:
http://cvs.php.net/viewcvs.cgi/ZendEngine2/zend.c?view=diff&r1=1.297&r2=1.298
which adds the opened file to the included_files list.  This means that 
we are now trying to add the main script to the included_file list twice 
which in itself is bad.

We'll test this a bit more, but it looks safe to remove that block of 
code.  The test case in bug 17720 works fine without that block of code 
in main.c and I see no other reason to have it there.

-Rasmus

Brian J. France wrote:
> 
> On Mar 10, 2006, at 1:57 AM, Rasmus Lerdorf wrote:
> 
>> Rasmus Lerdorf wrote:
>>> Andi Gutmans wrote:
>>>> Are you sure VCWD_REALPATH doesn't use the realpath cache? It did 
>>>> last time I checked and I think is still the right method to use 
>>>> there...
>>> quite
>>> #define VCWD_REALPATH(path, real_path) realpath(path, real_path)
>>
>> By the way, I agree that expand_filepath() is not the right fix here 
>> since the first thing it does is a getcwd.  We have just done a chdir 
>> and haven't executed any script yet so we know the cwd.  Feed that 
>> directly to virtual_file_ex() there perhaps?  I haven't really dug 
>> into it.
> 
> Were you seeing two getcwd calls?  I can remove one, but I don't see 
> away around the second one.  I changed to virtual_realpath which does 
> remove the getcwd in php_execute_script function, but it seems that is 
> shows up a little later when it uses the stream open which called 
> expand_filepath:
> 
> #0  0x203ab410 in __getcwd () from /usr/lib/libc.so.4
> #1  0x203b2ab6 in getcwd () from /usr/lib/libc.so.4
> #2  0x2060de86 in expand_filepath (filepath=0x2cbc08 
> "<path>/bench_main.php", real_path=0x0)
>     at main/fopen_wrappers.c:521
> #3  0x2061c1bd in _php_stream_fopen (filename=0x2cbc08 
> "<path>/bench_main.php", mode=0x206f1fe3 "rb",
>     opened_path=0x9fbff7cc, options=133)
>     at /main/streams/plain_wrapper.c:855
> #4  0x2061c974 in _php_stream_fopen_with_path (filename=0x2cbc08 
> "<path>/bench_main.php",
>     mode=0x206f1fe3 "rb", path=0x12b640 ".:/<path>/pear", 
> opened_path=0x9fbff7cc, options=133)
>     at /main/streams/plain_wrapper.c:1238
> #5  0x2061c338 in php_plain_files_stream_opener (wrapper=0x2077c008, 
> path=0x2cbc08
>     "<path>/bench_main.php", mode=0x206f1fe3 "rb", options=133, 
> opened_path=0x9fbff7cc, context=0x0)
>     at/main/streams/plain_wrapper.c:931
> #6  0x2061962e in _php_stream_open_wrapper_ex (path=0x2cbc08 
> "<path>bench_main.php",
>     mode=0x206f1fe3 "rb", options=141, opened_path=0x9fbff7cc, context=0x0)
>     at main/streams/streams.c:1771
> #7  0x2060943b in php_stream_open_for_zend (filename=0x2cbc08 
> "<path>/bench_main.php",
>     handle=0x9fbff7c4) at main/main.c:901
> #8  0x2064a866 in zend_stream_open (filename=0x2cbc08 
> "<path>/bench_main.php",
>     handle=0x9fbff7c4) at Zend/zend_stream.c:47
> #9  0x2064a8dc in zend_stream_fixup (file_handle=0x9fbff7c4) at 
> Zend/zend_stream.c:62
> #10 0x20623ee7 in open_file_for_scanning (file_handle=0x9fbff7c4) at 
> Zend/zend_language_scanner.c:2982
> #11 0x20623fce in compile_file (file_handle=0x9fbff7c4, type=2) at 
> Zend/zend_language_scanner.c:3068
> #12 0x2063cd1c in zend_execute_scripts (type=8, retval=0x0, 
> file_count=3) at Zend/zend.c:1093
> #13 0x2060a653 in php_execute_script (primary_file=0x9fbff7c4) at 
> main/main.c:1724
> 
> Brian