Use spaces for indentation, not tabs.
[gnulib.git] / m4 / fcntl_h.m4
index f2b09f3..40a1803 100644 (file)
@@ -1,3 +1,4 @@
+# serial 6
 # Configure fcntl.h.
 dnl Copyright (C) 2006, 2007, 2009 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
@@ -8,57 +9,70 @@ dnl Written by Paul Eggert.
 
 AC_DEFUN([gl_FCNTL_H],
 [
-  AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
   AC_REQUIRE([gl_FCNTL_H_DEFAULTS])
+  AC_REQUIRE([gl_FCNTL_O_FLAGS])
+  gl_CHECK_NEXT_HEADERS([fcntl.h])
+  FCNTL_H='fcntl.h'
+  AC_SUBST([FCNTL_H])
+])
+
+# Test whether the flags O_NOATIME and O_NOFOLLOW actually work.
+# Define HAVE_WORKING_O_NOATIME to 1 if O_NOATIME works, or to 0 otherwise.
+# Define HAVE_WORKING_O_NOFOLLOW to 1 if O_NOFOLLOW works, or to 0 otherwise.
+AC_DEFUN([gl_FCNTL_O_FLAGS],
+[
+  dnl Persuade glibc <fcntl.h> to define O_NOATIME and O_NOFOLLOW.
+  AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
   AC_CACHE_CHECK([for working fcntl.h], [gl_cv_header_working_fcntl_h],
     [AC_RUN_IFELSE(
        [AC_LANG_PROGRAM(
-         [[#include <sys/types.h>
-          #include <sys/stat.h>
-          #include <unistd.h>
-          #include <fcntl.h>
-          #ifndef O_NOATIME
-           #define O_NOATIME 0
-          #endif
-          #ifndef O_NOFOLLOW
-           #define O_NOFOLLOW 0
-          #endif
-          static int const constants[] =
-           {
-             O_CREAT, O_EXCL, O_NOCTTY, O_TRUNC, O_APPEND,
-             O_NONBLOCK, O_SYNC, O_ACCMODE, O_RDONLY, O_RDWR, O_WRONLY
-           };
-         ]],
-         [[
-           int status = !constants;
-           {
-             static char const sym[] = "conftest.sym";
-             if (symlink (".", sym) != 0
-                 || close (open (sym, O_RDONLY | O_NOFOLLOW)) == 0)
-               status |= 32;
-           }
-           {
-             static char const file[] = "confdefs.h";
-             int fd = open (file, O_RDONLY | O_NOATIME);
-             char c;
-             struct stat st0, st1;
-             if (fd < 0
-                 || fstat (fd, &st0) != 0
-                 || sleep (1) != 0
-                 || read (fd, &c, 1) != 1
-                 || close (fd) != 0
-                 || stat (file, &st1) != 0
-                 || st0.st_atime != st1.st_atime)
-               status |= 64;
-           }
-           return status;]])],
+          [[#include <sys/types.h>
+           #include <sys/stat.h>
+           #include <unistd.h>
+           #include <fcntl.h>
+           #ifndef O_NOATIME
+            #define O_NOATIME 0
+           #endif
+           #ifndef O_NOFOLLOW
+            #define O_NOFOLLOW 0
+           #endif
+           static int const constants[] =
+            {
+              O_CREAT, O_EXCL, O_NOCTTY, O_TRUNC, O_APPEND,
+              O_NONBLOCK, O_SYNC, O_ACCMODE, O_RDONLY, O_RDWR, O_WRONLY
+            };
+          ]],
+          [[
+            int status = !constants;
+            {
+              static char const sym[] = "conftest.sym";
+              if (symlink (".", sym) != 0
+                  || close (open (sym, O_RDONLY | O_NOFOLLOW)) == 0)
+                status |= 32;
+              unlink (sym);
+            }
+            {
+              static char const file[] = "confdefs.h";
+              int fd = open (file, O_RDONLY | O_NOATIME);
+              char c;
+              struct stat st0, st1;
+              if (fd < 0
+                  || fstat (fd, &st0) != 0
+                  || sleep (1) != 0
+                  || read (fd, &c, 1) != 1
+                  || close (fd) != 0
+                  || stat (file, &st1) != 0
+                  || st0.st_atime != st1.st_atime)
+                status |= 64;
+            }
+            return status;]])],
        [gl_cv_header_working_fcntl_h=yes],
        [case $? in #(
-       32) gl_cv_header_working_fcntl_h='no (bad O_NOFOLLOW)';; #(
-       64) gl_cv_header_working_fcntl_h='no (bad O_NOATIME)';; #(
-       96) gl_cv_header_working_fcntl_h='no (bad O_NOATIME, O_NOFOLLOW)';; #(
-        *) gl_cv_header_working_fcntl_h='no';;
-       esac],
+        32) gl_cv_header_working_fcntl_h='no (bad O_NOFOLLOW)';; #(
+        64) gl_cv_header_working_fcntl_h='no (bad O_NOATIME)';; #(
+        96) gl_cv_header_working_fcntl_h='no (bad O_NOATIME, O_NOFOLLOW)';; #(
+         *) gl_cv_header_working_fcntl_h='no';;
+        esac],
        [gl_cv_header_working_fcntl_h=cross-compiling])])
 
   case $gl_cv_header_working_fcntl_h in #(
@@ -74,10 +88,6 @@ AC_DEFUN([gl_FCNTL_H],
   esac
   AC_DEFINE_UNQUOTED([HAVE_WORKING_O_NOFOLLOW], [$ac_val],
     [Define to 1 if O_NOFOLLOW works.])
-
-  gl_CHECK_NEXT_HEADERS([fcntl.h])
-  FCNTL_H='fcntl.h'
-  AC_SUBST([FCNTL_H])
 ])
 
 AC_DEFUN([gl_FCNTL_MODULE_INDICATOR],
@@ -89,7 +99,10 @@ AC_DEFUN([gl_FCNTL_MODULE_INDICATOR],
 
 AC_DEFUN([gl_FCNTL_H_DEFAULTS],
 [
-  GNULIB_OPEN=0;  AC_SUBST([GNULIB_OPEN])
+  GNULIB_OPEN=0;    AC_SUBST([GNULIB_OPEN])
+  GNULIB_OPENAT=0;  AC_SUBST([GNULIB_OPENAT])
   dnl Assume proper GNU behavior unless another module says otherwise.
-  REPLACE_OPEN=0; AC_SUBST([REPLACE_OPEN])
+  HAVE_OPENAT=1;    AC_SUBST([HAVE_OPENAT])
+  REPLACE_OPEN=0;   AC_SUBST([REPLACE_OPEN])
+  REPLACE_OPENAT=0; AC_SUBST([REPLACE_OPENAT])
 ])