X-Git-Url: https://code.delx.au/gnu-emacs/blobdiff_plain/1259009aa17da6dc038afff96963f6d9bbd3b8e1..7f8e742833e058fa41c273ff35351b02b6e8d42b:/m4/largefile.m4

diff --git a/m4/largefile.m4 b/m4/largefile.m4
index d83fea1233..8bbdfaac1d 100644
--- a/m4/largefile.m4
+++ b/m4/largefile.m4
@@ -1,13 +1,14 @@
 # Enable large files on systems where this is not the default.
 
-# Copyright 1992-1996, 1998-2011 Free Software Foundation, Inc.
+# Copyright 1992-1996, 1998-2016 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.
 
-# The following implementation works around a problem in autoconf <= 2.68;
-# AC_SYS_LARGEFILE does not configure for large inodes on Mac OS X 10.5.
-m4_version_prereq([2.69], [] ,[
+# The following implementation works around a problem in autoconf <= 2.69;
+# AC_SYS_LARGEFILE does not configure for large inodes on Mac OS X 10.5,
+# or configures them incorrectly in some cases.
+m4_version_prereq([2.70], [] ,[
 
 # _AC_SYS_LARGEFILE_TEST_INCLUDES
 # -------------------------------
@@ -25,9 +26,9 @@ m4_define([_AC_SYS_LARGEFILE_TEST_INCLUDES],
 
 
 # _AC_SYS_LARGEFILE_MACRO_VALUE(C-MACRO, VALUE,
-#				CACHE-VAR,
-#				DESCRIPTION,
-#				PROLOGUE, [FUNCTION-BODY])
+#                               CACHE-VAR,
+#                               DESCRIPTION,
+#                               PROLOGUE, [FUNCTION-BODY])
 # --------------------------------------------------------
 m4_define([_AC_SYS_LARGEFILE_MACRO_VALUE],
 [AC_CACHE_CHECK([for $1 value needed for large files], [$3],
@@ -93,12 +94,53 @@ if test "$enable_largefile" != no; then
       [_AC_SYS_LARGEFILE_TEST_INCLUDES])
   fi
 
-  AH_VERBATIM([_DARWIN_USE_64_BIT_INODE],
-[/* Enable large inode numbers on Mac OS X.  */
-#ifndef _DARWIN_USE_64_BIT_INODE
-# define _DARWIN_USE_64_BIT_INODE 1
-#endif])
+  AC_DEFINE([_DARWIN_USE_64_BIT_INODE], [1],
+    [Enable large inode numbers on Mac OS X 10.5.])
 fi
 ])# AC_SYS_LARGEFILE
+])# m4_version_prereq 2.70
 
-])# m4_version_prereq 2.69
+# Enable large files on systems where this is implemented by Gnulib, not by the
+# system headers.
+# Set the variables WINDOWS_64_BIT_OFF_T, WINDOWS_64_BIT_ST_SIZE if Gnulib
+# overrides ensure that off_t or 'struct size.st_size' are 64-bit, respectively.
+AC_DEFUN([gl_LARGEFILE],
+[
+  AC_REQUIRE([AC_CANONICAL_HOST])
+  case "$host_os" in
+    mingw*)
+      dnl Native Windows.
+      dnl mingw64 defines off_t to a 64-bit type already, if
+      dnl _FILE_OFFSET_BITS=64, which is ensured by AC_SYS_LARGEFILE.
+      AC_CACHE_CHECK([for 64-bit off_t], [gl_cv_type_off_t_64],
+        [AC_COMPILE_IFELSE(
+           [AC_LANG_PROGRAM(
+              [[#include <sys/types.h>
+                int verify_off_t_size[sizeof (off_t) >= 8 ? 1 : -1];
+              ]],
+              [[]])],
+           [gl_cv_type_off_t_64=yes], [gl_cv_type_off_t_64=no])
+        ])
+      if test $gl_cv_type_off_t_64 = no; then
+        WINDOWS_64_BIT_OFF_T=1
+      else
+        WINDOWS_64_BIT_OFF_T=0
+      fi
+      dnl But all native Windows platforms (including mingw64) have a 32-bit
+      dnl st_size member in 'struct stat'.
+      WINDOWS_64_BIT_ST_SIZE=1
+      ;;
+    *)
+      dnl Nothing to do on gnulib's side.
+      dnl A 64-bit off_t is
+      dnl   - already the default on Mac OS X, FreeBSD, NetBSD, OpenBSD, IRIX,
+      dnl     OSF/1, Cygwin,
+      dnl   - enabled by _FILE_OFFSET_BITS=64 (ensured by AC_SYS_LARGEFILE) on
+      dnl     glibc, HP-UX, Solaris,
+      dnl   - enabled by _LARGE_FILES=1 (ensured by AC_SYS_LARGEFILE) on AIX,
+      dnl   - impossible to achieve on Minix 3.1.8.
+      WINDOWS_64_BIT_OFF_T=0
+      WINDOWS_64_BIT_ST_SIZE=0
+      ;;
+  esac
+])