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Message-ID: <41238053.6000205@ujf-grenoble.fr>
Date: Wed, 18 Aug 2004 18:14:11 +0200
From: Maurice Lombardi <Maurice DOT Lombardi AT ujf-grenoble DOT fr>
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To: djgpp-workers AT delorie DOT com
Subject: bug in __solve_symlink()
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Reply-To: djgpp-workers AT delorie DOT com

In a previous post
http://www.delorie.com/djgpp/mail-archives/browse.cgi?p=djgpp/2004/05/06/10:32:18
(see also
http://www.delorie.com/djgpp/mail-archives/browse.cgi?p=djgpp-workers/2004/05/07/07:03:40

I have described a bug in __solve_symlinks() for version 2.04 and proposed a solution.

I found recently that the corresponding test suite is in djtst204.zip
As expected the case I described was not covered by the tests.
I thus added a new test modelled from the previous one in the suite with the following diff

--- tests\libc\compat\unistd\xsymlink.c.orig	2003-02-10 21:41:10.000000000 +0000
+++ tests\libc\compat\unistd\xsymlink.c	2004-08-18 17:40:58.000000000 +0000
@@ -17,8 +17,10 @@
   *
   * There are some tests based on the current-working directory:
   *   1. An absolute path using '..' to navigate through the directories.
- *   2. A relative path using a drive letter and '..'.
- *   3. A relative path using a drive letter and one too many '..' over 2.
+ *   2. An absolute path without drive letter using '..' to navigate and
+ *      not ending in current-working directory.
+ *   3. A relative path using a drive letter and '..'.
+ *   4. A relative path using a drive letter and one too many '..' over 3.
   *
   * And following are failure tests:
   *   1. Simple symlink loop.
@@ -151,6 +153,29 @@
       if (!ret)
         ok = 0;

+
+     /* Try tests_success[2] with an absolute path without drive letter
+      * and with '..'. */
+     j++;
+
+     strcpy(path, cwd_without_drive);
+     for (i = 0; i < n_slashes; i++)
+     {
+       strcat(path, "/..");
+     }
+     strcat(path, cwd_without_drive);
+     strcat(path, "/");
+     strcat(path, tests_success[2].src);
+
+     test.src    = path;
+     test.target = tests_success[2].target;
+
+     printf("Test %d: Solving %s\n", j, test.src);
+     ret = test_success(j, test.src, test.target);
+     if (!ret)
+       ok = 0;
+
+
       /* Try tests_success[0] with a drive-letter and relative path
        * with '..'. */
       j++;

---------------------------------------------------------------------------------

running the test with the current beta 1 gives

DJ204 C:\dj204\tests\libc\compat\unistd>xsymlink
Running __solve_symlinks() and readlink() testsuite:
Tests that check __solve_symlinks() works:
Test 1 passed
Test 2 passed
Test 3 passed
Test 4 passed
Test 5 passed
Test 6 passed
Test 7 passed
Test 8 passed
Test 9 passed
Test 10 passed
Test 11 passed
Test 12 passed
Test 13 passed
Tests that check __solve_symlinks() based on current directory:
Test 1: Solving c:/dj204/tests/libc/compat/unistd/../../../../../dj204/tests/lib
c/compat/unistd/test1
Test 1 passed
Test 2: Solving /dj204/tests/libc/compat/unistd/../../../../../dj204/tests/libc/
compat/unistd/dir1/test1
Test 2 failed - __solve_symlinks returns wrong resolved path
Returned path: c:/dj204/tests/libc/compat/unistd/file1
Expected path: c:/dj204/tests/libc/compat/unistd/dir1/file1
Test 3: Solving c:../../../../../dj204/tests/libc/compat/unistd/test1
Test 3 passed
Test 4: Solving c:../../../../../../dj204/tests/libc/compat/unistd/test1
Test 4 failed - __solve_symlinks returns wrong resolved path
Returned path: c:/dj204/tests/libc/compat/unistd/test1
Expected path: c:/dj204/tests/libc/compat/unistd/file1
Tests that check __solve_symlinks() failure cases:
Test 1 passed
Test 2 passed
FAIL

Test 2 in the second series is the new one and it fails as expected
---------------------------------------------------------------------------------
appling the proposed diff

--- src\libc\compat\unistd\xsymlink.c.orig	2003-02-06 20:42:38.000000000 +0000
+++ src\libc\compat\unistd\xsymlink.c	2004-08-02 15:57:42.000000000 +0000
@@ -74,7 +74,9 @@
      */
     start = __real_path;
     end = strpbrk(__real_path, "/\\");
-   if (!end || (start == end))
+   if (start == end)
+      end = strpbrk(__real_path + 1, "/\\");
+   if (!end)
        end = __real_path + strlen(__real_path);
     while (start && *start)
     {

---------------------------------------------------------------------------------------

recompiling src and running the same test gives

DJ204 C:\dj204\tests\libc\compat\unistd>xsymlink
Running __solve_symlinks() and readlink() testsuite:
Tests that check __solve_symlinks() works:
Test 1 passed
Test 2 passed
Test 3 passed
Test 4 passed
Test 5 passed
Test 6 passed
Test 7 passed
Test 8 passed
Test 9 passed
Test 10 passed
Test 11 passed
Test 12 passed
Test 13 passed
Tests that check __solve_symlinks() based on current directory:
Test 1: Solving c:/dj204/tests/libc/compat/unistd/../../../../../dj204/tests/lib
c/compat/unistd/test1
Test 1 passed
Test 2: Solving /dj204/tests/libc/compat/unistd/../../../../../dj204/tests/libc/
compat/unistd/dir1/test1
Test 2 passed
Test 3: Solving c:../../../../../dj204/tests/libc/compat/unistd/test1
Test 3 passed
Test 4: Solving c:../../../../../../dj204/tests/libc/compat/unistd/test1
Test 4 failed - __solve_symlinks returns wrong resolved path
Returned path: c:/dj204/tests/libc/compat/unistd/test1
Expected path: c:/dj204/tests/libc/compat/unistd/file1
Tests that check __solve_symlinks() failure cases:
Test 1 passed
Test 2 passed
FAIL

Test 2 of the second series now succeeds as expected.

Test 4 which fails in both cases was described in a thread on djgpp-workers
in 2003/02: it occurs with Win98se (I use), not with Win2k, and apparently
it remained as is since then.

Hope this helps

Maurice

-- 
        Maurice Lombardi
Laboratoire de  Spectrometrie Physique,
Universite Joseph Fourier de Grenoble, BP87
38402 Saint Martin d'Heres Cedex     FRANCE
Tel: 33 (0)4 76 51 47 51
Fax: 33 (0)4 76 63 54 95
mailto:Maurice DOT Lombardi AT ujf-grenoble DOT fr