X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=m4%2Fopenat.m4;h=affb11455586a8c834c72ce11db1bc4518bea828;hb=d5bdbf8fefafcbcc1e64c207f8af9109633ba668;hp=42df3ee72d90df2b317a402d29ce8ebe35e2e7e3;hpb=4c45e93c58de6532275c22a9153ecdfe516928ff;p=gnulib.git

diff --git a/m4/openat.m4 b/m4/openat.m4
index 42df3ee72..affb11455 100644
--- a/m4/openat.m4
+++ b/m4/openat.m4
@@ -1,7 +1,7 @@
-# serial 24
+# serial 33
 # See if we need to use our replacement for Solaris' openat et al functions.
 
-dnl Copyright (C) 2004-2009 Free Software Foundation, Inc.
+dnl Copyright (C) 2004-2011 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
 dnl with or without modifications, as long as this notice is preserved.
@@ -22,21 +22,22 @@ AC_DEFUN([gl_FUNC_OPENAT],
   GNULIB_FCHOWNAT=1
   GNULIB_UNLINKAT=1
 
-  AC_LIBOBJ([openat-proc])
   AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
   AC_CHECK_FUNCS_ONCE([lchmod])
-  AC_REPLACE_FUNCS([fchmodat fstatat mkdirat openat unlinkat])
-  AC_REQUIRE([AC_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK])
-  case $ac_cv_func_openat+$ac_cv_func_lstat_dereferences_slashed_symlink in
-  yes+yes) ;;
+  AC_CHECK_FUNCS([fchmodat fstatat mkdirat openat unlinkat])
+  AC_REQUIRE([gl_FUNC_LSTAT_FOLLOWS_SLASHED_SYMLINK])
+  AC_REQUIRE([gl_FUNC_UNLINK])
+  case $ac_cv_func_openat+$gl_cv_func_lstat_dereferences_slashed_symlink in
+  yes+yes)
+    # GNU/Hurd has unlinkat, but it has the same bug as unlink.
+    if test $REPLACE_UNLINK = 1; then
+      REPLACE_UNLINKAT=1
+    fi ;;
   yes+*)
     # Solaris 9 has *at functions, but uniformly mishandles trailing
     # slash in all of them.
-    AC_LIBOBJ([openat])
     REPLACE_OPENAT=1
-    AC_LIBOBJ([fstatat])
     REPLACE_FSTATAT=1
-    AC_LIBOBJ([unlinkat])
     REPLACE_UNLINKAT=1
     ;;
   *)
@@ -57,6 +58,9 @@ AC_DEFUN([gl_FUNC_OPENAT],
 # gl_FUNC_FCHOWNAT_DEREF_BUG([ACTION-IF-BUGGY[, ACTION-IF-NOT_BUGGY]])
 AC_DEFUN([gl_FUNC_FCHOWNAT_DEREF_BUG],
 [
+  dnl Persuade glibc's <unistd.h> to declare fchownat().
+  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
+
   AC_CACHE_CHECK([whether fchownat works with AT_SYMLINK_NOFOLLOW],
     gl_cv_func_fchownat_nofollow_works,
     [
@@ -68,7 +72,7 @@ AC_DEFUN([gl_FUNC_FCHOWNAT_DEREF_BUG],
      ln -s conftest.no-such $gl_dangle
      AC_RUN_IFELSE(
        [AC_LANG_SOURCE(
-	  [[
+          [[
 #include <fcntl.h>
 #include <unistd.h>
 #include <stdlib.h>
@@ -78,10 +82,10 @@ int
 main ()
 {
   return (fchownat (AT_FDCWD, "$gl_dangle", -1, getgid (),
-		    AT_SYMLINK_NOFOLLOW) != 0
-	  && errno == ENOENT);
+                    AT_SYMLINK_NOFOLLOW) != 0
+          && errno == ENOENT);
 }
-	  ]])],
+          ]])],
     [gl_cv_func_fchownat_nofollow_works=yes],
     [gl_cv_func_fchownat_nofollow_works=no],
     [gl_cv_func_fchownat_nofollow_works=no],
@@ -90,22 +94,70 @@ main ()
   AS_IF([test $gl_cv_func_fchownat_nofollow_works = no], [$1], [$2])
 ])
 
+# gl_FUNC_FCHOWNAT_EMPTY_FILENAME_BUG([ACTION-IF-BUGGY[, ACTION-IF-NOT_BUGGY]])
+AC_DEFUN([gl_FUNC_FCHOWNAT_EMPTY_FILENAME_BUG],
+[
+  dnl Persuade glibc's <unistd.h> to declare fchownat().
+  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
+
+  AC_CACHE_CHECK([whether fchownat works with an empty file name],
+    [gl_cv_func_fchownat_empty_filename_works],
+    [AC_RUN_IFELSE(
+       [AC_LANG_PROGRAM(
+          [[#include <unistd.h>
+            #include <fcntl.h>
+          ]],
+          [[int fd;
+            int ret;
+            if (mkdir ("conftestdir", 0700) < 0)
+              return 2;
+            fd = open ("conftestdir", O_RDONLY);
+            if (fd < 0)
+              return 3;
+            ret = fchownat (fd, "", -1, -1, 0);
+            close (fd);
+            rmdir ("conftestdir");
+            return ret == 0;
+          ]])],
+       [gl_cv_func_fchownat_empty_filename_works=yes],
+       [gl_cv_func_fchownat_empty_filename_works=no],
+       [gl_cv_func_fchownat_empty_filename_works="guessing no"])
+    ])
+  AS_IF([test "$gl_cv_func_fchownat_empty_filename_works" != yes], [$1], [$2])
+])
+
 # If we have the fchownat function, and it has the bug (in glibc-2.4)
 # that it dereferences symlinks even with AT_SYMLINK_NOFOLLOW, then
 # use the replacement function.
+# Also if the fchownat function, like chown, has the trailing slash bug,
+# use the replacement function.
 # Also use the replacement function if fchownat is simply not available.
 AC_DEFUN([gl_FUNC_FCHOWNAT],
 [
+  AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
+  AC_REQUIRE([gl_FUNC_CHOWN])
   AC_CHECK_FUNC([fchownat],
-    [gl_FUNC_FCHOWNAT_DEREF_BUG([REPLACE_FCHOWNAT=1])],
+    [gl_FUNC_FCHOWNAT_DEREF_BUG(
+       [REPLACE_FCHOWNAT=1
+        AC_DEFINE([FCHOWNAT_NOFOLLOW_BUG], [1],
+                  [Define to 1 if your platform has fchownat, but it cannot
+                   perform lchown tasks.])
+       ])
+     gl_FUNC_FCHOWNAT_EMPTY_FILENAME_BUG(
+       [REPLACE_FCHOWNAT=1
+        AC_DEFINE([FCHOWNAT_EMPTY_FILENAME_BUG], [1],
+                  [Define to 1 if your platform has fchownat, but it does
+                   not reject an empty file name.])
+       ])
+     if test $REPLACE_CHOWN = 1; then
+       REPLACE_FCHOWNAT=1
+     fi],
     [HAVE_FCHOWNAT=0])
-  if test $HAVE_FCHOWNAT = 0 || test $REPLACE_FCHOWNAT = 1; then
-    AC_LIBOBJ([fchownat])
-  fi
 ])
 
 AC_DEFUN([gl_PREREQ_OPENAT],
 [
+  AC_REQUIRE([AC_C_INLINE])
   AC_REQUIRE([gl_PROMOTED_TYPE_MODE_T])
   :
 ])