finalise NEWS.stable

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

diff --git a/m4/getcwd-abort-bug.m4 b/m4/getcwd-abort-bug.m4
index fd6820d..057cc47 100644 (file)
--- a/m4/getcwd-abort-bug.m4
+++ b/m4/getcwd-abort-bug.m4
@@ -1,4 +1,4 @@
-# serial 4
+# serial 7
 # 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.
@@ -14,6 +14,8 @@
 AC_DEFUN([gl_FUNC_GETCWD_ABORT_BUG],
 [
   AC_CHECK_DECLS_ONCE([getcwd])
+  AC_CHECK_HEADERS_ONCE([unistd.h])
+  AC_REQUIRE([gl_PATHMAX_SNIPPET_PREREQ])
   AC_CHECK_FUNCS([getpagesize])
   AC_CACHE_CHECK([whether getcwd aborts when 4k < cwd_length < 16k],
     gl_cv_func_getcwd_abort_bug,
@@ -26,11 +28,16 @@ AC_DEFUN([gl_FUNC_GETCWD_ABORT_BUG],
        [AC_LANG_SOURCE(
           [[
 #include <stdlib.h>
-#include <unistd.h>
-#include <limits.h>
+#if HAVE_UNISTD_H
+# include <unistd.h>
+#else /* on Windows with MSVC */
+# include <direct.h>
+#endif
 #include <string.h>
 #include <sys/stat.h>
 
+]gl_PATHMAX_SNIPPET[
+
 /* Don't get link errors because mkdir is redefined to rpl_mkdir.  */
 #undef mkdir
 
@@ -84,7 +91,8 @@ main ()
      results in a failed assertion.  */
   cwd = getcwd (NULL, 0);
   if (cwd == NULL)
-    fail = 4; /* getcwd failed.  This is ok, and expected.  */
+    fail = 4; /* getcwd failed: it refuses to return a string longer
+                 than PATH_MAX.  */
   free (cwd);
 
   /* Call rmdir first, in case the above chdir failed.  */
@@ -103,11 +111,18 @@ main ()
 }
           ]])],
     [gl_cv_func_getcwd_abort_bug=no],
-    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 $? -gt 128 \
-      && gl_cv_func_getcwd_abort_bug=yes \
-      || gl_cv_func_getcwd_abort_bug=no],
+    [dnl An abort will provoke an exit code of something like 134 (128 + 6).
+     dnl An exit code of 4 can also occur (in OpenBSD 4.9, NetBSD 5.1 for
+     dnl example): getcwd (NULL, 0) fails rather than returning a string
+     dnl longer than PATH_MAX.  This may be POSIX compliant (in some
+     dnl interpretations of POSIX).  But gnulib's getcwd module wants to
+     dnl provide a non-NULL value in this case.
+     ret=$?
+     if test $ret -ge 128 || test $ret = 4; then
+       gl_cv_func_getcwd_abort_bug=yes
+     else
+       gl_cv_func_getcwd_abort_bug=no
+     fi],
     [gl_cv_func_getcwd_abort_bug=yes])
   ])
   AS_IF([test $gl_cv_func_getcwd_abort_bug = yes], [$1], [$2])