openat: test for fstatat (AT_FDCWD, ..., 0) bug

[gnulib.git] / m4 / fsusage.m4

diff --git a/m4/fsusage.m4 b/m4/fsusage.m4
index 41c06bc..8e9e2cb 100644 (file)
--- a/m4/fsusage.m4
+++ b/m4/fsusage.m4
@@ -1,4 +1,4 @@
-# serial 28
+# serial 29
 # Obtaining file system usage information.
 
 # Copyright (C) 1997-1998, 2000-2001, 2003-2011 Free Software Foundation, Inc.
@@ -29,6 +29,12 @@ AC_DEFUN([gl_FSUSAGE],
 
 AC_DEFUN([gl_FILE_SYSTEM_USAGE],
 [
+dnl Enable large-file support. This has the effect of changing the size
+dnl of field f_blocks in 'struct statvfs' from 32 bit to 64 bit on
+dnl glibc/Hurd, HP-UX 11, Solaris (32-bit mode). It also changes the size
+dnl of field f_blocks in 'struct statfs' from 32 bit to 64 bit on
+dnl MacOS X >= 10.5 (32-bit mode).
+AC_REQUIRE([AC_SYS_LARGEFILE])
 
 AC_MSG_NOTICE([checking how to get file system space usage])
 ac_fsusage_space=no
@@ -56,22 +62,51 @@ a system call.
 "Do not use Tru64's statvfs implementation"
 #endif
 
-#include <limits.h>
 #include <sys/statvfs.h>
 
-/* Reject implementations, such as MacOS X 10.7, where f_blocks is a
-   32-bit quantity; that commonly limits file systems to 4 TiB, a
-   ridiculously small limit these days.  */
 struct statvfs fsd;
+
+#if defined __APPLE__ && defined __MACH__
+#include <limits.h>
+/* On MacOS X >= 10.5, f_blocks in 'struct statvfs' is a 32-bit quantity;
+   that commonly limits file systems to 4 TiB.  Whereas f_blocks in
+   'struct statfs' is a 64-bit type, thanks to the large-file support
+   that was enabled above.  In this case, don't use statvfs(); use statfs()
+   instead.  */
 int check_f_blocks_size[sizeof fsd.f_blocks * CHAR_BIT <= 32 ? -1 : 1];
+#endif
 ]],
                                     [[statvfs (0, &fsd);]])],
                                  [fu_cv_sys_stat_statvfs=yes],
                                  [fu_cv_sys_stat_statvfs=no])])
   if test $fu_cv_sys_stat_statvfs = yes; then
     ac_fsusage_space=yes
-    AC_DEFINE([STAT_STATVFS], [1],
-              [  Define if there is a function named statvfs.  (SVR4)])
+    # AIX >= 5.2 has statvfs64 that has a wider f_blocks field than statvfs.
+    # glibc, HP-UX, IRIX, Solaris have statvfs64 as well, but on these systems
+    # statvfs with large-file support is already equivalent to statvfs64.
+    AC_CACHE_CHECK([whether to use statvfs64],
+      [fu_cv_sys_stat_statvfs64],
+      [AC_LINK_IFELSE(
+         [AC_LANG_PROGRAM(
+            [[#include <sys/types.h>
+              #include <sys/statvfs.h>
+              struct statvfs64 fsd;
+              int check_f_blocks_larger_in_statvfs64
+                [sizeof (((struct statvfs64 *) 0)->f_blocks)
+                 > sizeof (((struct statvfs *) 0)->f_blocks)
+                 ? 1 : -1];
+            ]],
+            [[statvfs64 (0, &fsd);]])],
+         [fu_cv_sys_stat_statvfs64=yes],
+         [fu_cv_sys_stat_statvfs64=no])
+      ])
+    if test $fu_cv_sys_stat_statvfs64 = yes; then
+      AC_DEFINE([STAT_STATVFS64], [1],
+                [  Define if statvfs64 should be preferred over statvfs.])
+    else
+      AC_DEFINE([STAT_STATVFS], [1],
+                [  Define if there is a function named statvfs.  (SVR4)])
+    fi
   fi
 fi