Merge commit 'stable/20110609'

[gnulib.git] / m4 / getcwd-abort-bug.m4

diff --git a/m4/getcwd-abort-bug.m4 b/m4/getcwd-abort-bug.m4
index 07e2c18..fd6820d 100644 (file)
--- a/m4/getcwd-abort-bug.m4
+++ b/m4/getcwd-abort-bug.m4
@@ -1,9 +1,9 @@
-# serial 2
+# serial 4
 # Determine whether getcwd aborts when the length of the working directory
 # name is unusually large.  Any length between 4k and 16k trigger the bug
 # when using glibc-2.4.90-9 or older.
 
-# Copyright (C) 2006, 2009 Free Software Foundation, Inc.
+# Copyright (C) 2006, 2009-2011 Free Software Foundation, Inc.
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
 # with or without modifications, as long as this notice is preserved.
@@ -21,9 +21,10 @@ AC_DEFUN([gl_FUNC_GETCWD_ABORT_BUG],
      rm -rf confdir-14B---
      # Arrange for deletion of the temporary directory this test creates.
      ac_clean_files="$ac_clean_files confdir-14B---"
+     dnl Please keep this in sync with tests/test-getcwd.c.
      AC_RUN_IFELSE(
        [AC_LANG_SOURCE(
-         [[
+          [[
 #include <stdlib.h>
 #include <unistd.h>
 #include <limits.h>
@@ -58,25 +59,25 @@ main ()
   size_t d;
 
   /* The bug is triggered when PATH_MAX < getpagesize (), so skip
-     this relative expensive and invasive test if that's not true.  */
+     this relatively expensive and invasive test if that's not true.  */
   if (getpagesize () <= PATH_MAX)
     return 0;
 
   cwd = getcwd (NULL, 0);
   if (cwd == NULL)
-    return 0;
+    return 2;
 
   initial_cwd_len = strlen (cwd);
   free (cwd);
   desired_depth = ((TARGET_LEN - 1 - initial_cwd_len)
-                  / (1 + strlen (dir_name)));
+                   / (1 + strlen (dir_name)));
   for (d = 0; d < desired_depth; d++)
     {
       if (mkdir (dir_name, S_IRWXU) < 0 || chdir (dir_name) < 0)
-       {
-         fail = 3; /* Unable to construct deep hierarchy.  */
-         break;
-       }
+        {
+          fail = 3; /* Unable to construct deep hierarchy.  */
+          break;
+        }
     }
 
   /* If libc has the bug in question, this invocation of getcwd
@@ -91,15 +92,22 @@ main ()
   while (0 < d--)
     {
       if (chdir ("..") < 0)
-       break;
+        {
+          fail = 5;
+          break;
+        }
       rmdir (dir_name);
     }
 
-  return 0;
+  return fail;
 }
           ]])],
     [gl_cv_func_getcwd_abort_bug=no],
-    [gl_cv_func_getcwd_abort_bug=yes],
+    dnl A "regular" nonzero return does not indicate this bug.
+    dnl An abort will provoke an exit code of something like 134 (128 + 6).
+    [test $? -gt 128 \
+      && gl_cv_func_getcwd_abort_bug=yes \
+      || gl_cv_func_getcwd_abort_bug=no],
     [gl_cv_func_getcwd_abort_bug=yes])
   ])
   AS_IF([test $gl_cv_func_getcwd_abort_bug = yes], [$1], [$2])