ID: 35791
Updated by: [EMAIL PROTECTED]
Reported By: jgmtfia at gmail dot com
-Status: Open
+Status: Feedback
Bug Type: Filesystem function related
Operating System: Linux
PHP Version: 5CVS-2006-01-03 (snap)
New Comment:
Configure PHP with this configure line:
# rm config.cache ; ./configure --disable-all --disable-cgi
--enable-debug
# make
Then test, if it fails -> send your main/php_config.h to me.
Previous Comments:
------------------------------------------------------------------------
[2006-01-03 17:19:45] jgmtfia at gmail dot com
I want to ensure that I have made my point clear. I have made a
simplier example, and have included an edited strace of PHP built from
yesterdays source.
The test:
<?php
`touch A; ln -s A C`;
echo "Checking A.\n";
if(!file_exists('A')){
echo "A does not exist.\n";
exit;
}
echo "Checking C.\n";
if(!file_exists('C')){
echo "C does not exist.\n";
exit;
}
echo "Unlinking C.\n";
unlink('C');
clearstatcache();
echo "Checking C: ";
if(file_exists('C'))
echo "(FAIL) exists\n";
?>
The ouput:
Checking A.
Checking C.
Unlinking C.
Checking C: (FAIL) exists
The edited strace:
write(1, "Checking A.\n", 12)
lstat64("/home", ...) = 0
lstat64("/home/user", ...) = 0
lstat64("/home/user/x", ...) = 0
lstat64("/home/user/x/A", ...) = 0
access("/home/user/x/A", F_OK) = 0
write(1, "Checking C.\n", 12)
lstat64("/home", ...) = 0
lstat64("/home/user", = 0
lstat64("/home/user/x", = 0
lstat64("/home/user/x/C", = 0
readlink("/home/user/x/C", "A", 4096) = 1
lstat64("/home/user/x/A", ...) = 0
access("/home/user/x/A", F_OK) = 0
write(1, "Unlinking C.\n", 13) = 13
unlink("/home/user/x/C") = 0
write(1, "Checking C: ", 12) = 12
***ERROR SHOULD BE "/home/user/x/C" BELOW ***
access("/home/user/x/A", F_OK) = 0
***END***
write(1, "(FAIL) exists\n", 14) = 14
So the question is why is PHP calling access("/home/user/x/A") when the
code calls file_exists('C')?
Also note that if the file_exists('C') call is removed from the start
code, the code then executes correctly.
<?php
`touch A; ln -s A C`;
echo "Unlinking C.\n";
unlink('C');
clearstatcache();
echo "Checking C: ";
if(file_exists('C'))
echo "(FAIL) exists\n";
?>
I don't know if it would be the operating system that would cause PHP
to access("/home/user/x/A") when I call file_exists('C').
debain php4.3.10-15 does pass the test and there are no lstat64 or
readlink calls.
write(1, "Checking A.\n", 12) = 12
access("A", F_OK) = 0
write(1, "Checking C.\n", 12) = 12
access("C", F_OK) = 0
write(1, "Unlinking C.\n", 13) = 13
unlink("C") = 0
write(1, "Checking C: ", 12) = 12
access("C", F_OK) = -1 ENOENT (No such file or directory)
------------------------------------------------------------------------
[2006-01-02 20:23:03] [EMAIL PROTECTED]
Works fine with working OS. Debian "stable" apparently isn't one of
these. (tested with RHEL4 and FC4)
------------------------------------------------------------------------
[2006-01-02 18:02:08] jgmtfia at gmail dot com
I have trimmed the strace output, but I can provide full output if
necessary.
It works in with PHP 4.3.10-15 on debian stable:
access("C", F_OK) = 0
pipe([3, 7]) = 0
vfork() = 10336
--- SIGCHLD (Child exited) @ 0 (0) ---
close(7) = 0
fstat64(3, {st_mode=S_IFIFO|0600, st_size=0, ...}) = 0
mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1,
0) = 0xb79d8000
read(3, "lrwxr-xr-x 1 1 Jan 2 09:48 C -"..., 4096) = 36
read(3, "", 4096) = 0
read(3, "", 4096) = 0
close(3) = 0
waitpid(10336, [{WIFEXITED(s) && WEXITSTATUS(s) == 0}], 0) = 10336
munmap(0xb79d8000, 4096) = 0
fstat64(1, {st_mode=S_IFREG|0644, st_size=0, ...}) = 0
mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1,
0) = 0xb79d8000
write(1, "File \'C\' exists:\n\t\tlrwxr-xr-x 1"..., 56) = 56
unlink("C") = 0
pipe([3, 7]) = 0
vfork() = 10338
close(7) = 0
fstat64(3, {st_mode=S_IFIFO|0600, st_size=0, ...}) = 0
mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1,
0) = 0xb79d7000
read(3, "ls: ", 4096) = 4
--- SIGCHLD (Child exited) @ 0 (0) ---
read(3, "C: No such file or directory\n", 4096) = 29
read(3, "", 4096) = 0
read(3, "", 4096) = 0
close(3) = 0
waitpid(10338, [{WIFEXITED(s) && WEXITSTATUS(s) == 1}], 0) = 10338
munmap(0xb79d7000, 4096) = 0
write(1, "Deleted \'C\'\n\t\tls: C: No such fil"..., 48) = 48
access("C", F_OK) = -1 ENOENT (No such file or
directory)
write(1, "(PASS) PHP sees the file as dele"..., 37) = 37
With php5.1-200601021330:
The link /home/user/C gets translated to /home/user/x/A and what should
be accesses to /home/user/C are accesses to /home/user/A as seen in the
second last line of the following strace.
lstat64("/home", {st_mode=S_IFDIR|S_ISGID|0775, st_size=4096, ...}) =
0
lstat64("/home/user", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
lstat64("/home/user/x", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
lstat64("/home/user/x/C", {st_mode=S_IFLNK|0755, st_size=1, ...}) = 0
readlink("/home/user/x/C", "A", 4096) = 1
lstat64("/home/user/x/A", {st_mode=S_IFREG|0644, st_size=0, ...}) = 0
access("/home/user/x/A", F_OK) = 0
pipe([3, 4]) = 0
vfork() = 10221
close(4) = 0
fstat64(3, {st_mode=S_IFIFO|0600, st_size=0, ...}) = 0
mmap2(NULL, 0, PROT_READ, MAP_SHARED, 3, 0) = -1 ENODEV (No such
device)
fstat64(3, {st_mode=S_IFIFO|0600, st_size=0, ...}) = 0
read(3, "lrwxr-xr-x 1 1 Jan 2 09:23 C -"..., 8192) = 36
read(3, "", 8192) = 0
close(3) = 0
waitpid(10221, [{WIFEXITED(s) && WEXITSTATUS(s) == 0}], 0) = 10221
--- SIGCHLD (Child exited) @ 0 (0) ---
fstat64(1, {st_mode=S_IFREG|0644, st_size=0, ...}) = 0
mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1,
0) = 0xb7fe8000
write(1, "File \'C\' exists:\n\t\tlrwxr-xr-x 1"..., 56) = 56
unlink("/home/user/x/C") = 0
pipe([3, 4]) = 0
vfork() = 10223
close(4) = 0
fstat64(3, {st_mode=S_IFIFO|0600, st_size=0, ...}) = 0
mmap2(NULL, 0, PROT_READ, MAP_SHARED, 3, 0) = -1 ENODEV (No such
device)
fstat64(3, {st_mode=S_IFIFO|0600, st_size=0, ...}) = 0
read(3, "ls: ", 8192) = 4
read(3, "C", 8192) = 1
read(3, ": No such file or directory", 8192) = 27
read(3, "\n", 8192) = 1
read(3, "", 8192) = 0
close(3) = 0
waitpid(10223, [{WIFEXITED(s) && WEXITSTATUS(s) == 1}], 0) = 10223
--- SIGCHLD (Child exited) @ 0 (0) ---
write(1, "Deleted \'C\'\n\t\tls: C: No such fil"..., 48) = 48
time(NULL) = 1136219020
access("/home/user/x/A", F_OK) = 0
write(1, "(FAIL) File \'C\' deleted as seen "..., 40) = 40
------------------------------------------------------------------------
[2006-01-02 17:15:11] [EMAIL PROTECTED]
You can strace the script and see what files are actually being
accessed.
------------------------------------------------------------------------
[2006-01-02 17:10:27] jgmtfia at gmail dot com
I tested the "lastest" version (php5.1-200601021330) on debian stable
and it failed. Over the holidays I tried 5.1.1 with debian testing and
it passed.
A summary of results:
4.3.10 - debian stable - pass
5.1.0b3 - debian stable - fail
5.1.0 - debian stable - fail
5.1.1 - debian stable - fail
5.1.1 - debian testing - pass
php5.1-200601021330 - debian stable - fail
5.1.2RC2-dev - SUSE Linux 10 x86_64 - pass
Common to all failures is Debian stable. Do you have any suggestions
on how to approach finding what is causing the fault?
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The remainder of the comments for this report are too long. To view
the rest of the comments, please view the bug report online at
http://bugs.php.net/35791
--
Edit this bug report at http://bugs.php.net/?id=35791&edit=1
