1# Enable large files on systems where this is not the default.
2
3# Copyright 1992-1996, 1998-2012 Free Software Foundation, Inc.
4# This file is free software; the Free Software Foundation
5# gives unlimited permission to copy and/or distribute it,
6# with or without modifications, as long as this notice is preserved.
7
8# The following implementation works around a problem in autoconf <= 2.68;
9# AC_SYS_LARGEFILE does not configure for large inodes on Mac OS X 10.5.
10m4_version_prereq([2.69], [] ,[
11
12# _AC_SYS_LARGEFILE_TEST_INCLUDES
13# -------------------------------
14m4_define([_AC_SYS_LARGEFILE_TEST_INCLUDES],
15[@%:@include <sys/types.h>
16 /* Check that off_t can represent 2**63 - 1 correctly.
17    We can't simply define LARGE_OFF_T to be 9223372036854775807,
18    since some C++ compilers masquerading as C compilers
19    incorrectly reject 9223372036854775807.  */
20@%:@define LARGE_OFF_T (((off_t) 1 << 62) - 1 + ((off_t) 1 << 62))
21  int off_t_is_large[[(LARGE_OFF_T % 2147483629 == 721
22                       && LARGE_OFF_T % 2147483647 == 1)
23                      ? 1 : -1]];[]dnl
24])
25
26
27# _AC_SYS_LARGEFILE_MACRO_VALUE(C-MACRO, VALUE,
28#				CACHE-VAR,
29#				DESCRIPTION,
30#				PROLOGUE, [FUNCTION-BODY])
31# --------------------------------------------------------
32m4_define([_AC_SYS_LARGEFILE_MACRO_VALUE],
33[AC_CACHE_CHECK([for $1 value needed for large files], [$3],
34[while :; do
35  m4_ifval([$6], [AC_LINK_IFELSE], [AC_COMPILE_IFELSE])(
36    [AC_LANG_PROGRAM([$5], [$6])],
37    [$3=no; break])
38  m4_ifval([$6], [AC_LINK_IFELSE], [AC_COMPILE_IFELSE])(
39    [AC_LANG_PROGRAM([@%:@define $1 $2
40$5], [$6])],
41    [$3=$2; break])
42  $3=unknown
43  break
44done])
45case $$3 in #(
46  no | unknown) ;;
47  *) AC_DEFINE_UNQUOTED([$1], [$$3], [$4]);;
48esac
49rm -rf conftest*[]dnl
50])# _AC_SYS_LARGEFILE_MACRO_VALUE
51
52
53# AC_SYS_LARGEFILE
54# ----------------
55# By default, many hosts won't let programs access large files;
56# one must use special compiler options to get large-file access to work.
57# For more details about this brain damage please see:
58# http://www.unix-systems.org/version2/whatsnew/lfs20mar.html
59AC_DEFUN([AC_SYS_LARGEFILE],
60[AC_ARG_ENABLE(largefile,
61               [  --disable-largefile     omit support for large files])
62if test "$enable_largefile" != no; then
63
64  AC_CACHE_CHECK([for special C compiler options needed for large files],
65    ac_cv_sys_largefile_CC,
66    [ac_cv_sys_largefile_CC=no
67     if test "$GCC" != yes; then
68       ac_save_CC=$CC
69       while :; do
70         # IRIX 6.2 and later do not support large files by default,
71         # so use the C compiler's -n32 option if that helps.
72         AC_LANG_CONFTEST([AC_LANG_PROGRAM([_AC_SYS_LARGEFILE_TEST_INCLUDES])])
73         AC_COMPILE_IFELSE([], [break])
74         CC="$CC -n32"
75         AC_COMPILE_IFELSE([], [ac_cv_sys_largefile_CC=' -n32'; break])
76         break
77       done
78       CC=$ac_save_CC
79       rm -f conftest.$ac_ext
80    fi])
81  if test "$ac_cv_sys_largefile_CC" != no; then
82    CC=$CC$ac_cv_sys_largefile_CC
83  fi
84
85  _AC_SYS_LARGEFILE_MACRO_VALUE(_FILE_OFFSET_BITS, 64,
86    ac_cv_sys_file_offset_bits,
87    [Number of bits in a file offset, on hosts where this is settable.],
88    [_AC_SYS_LARGEFILE_TEST_INCLUDES])
89  if test $ac_cv_sys_file_offset_bits = unknown; then
90    _AC_SYS_LARGEFILE_MACRO_VALUE(_LARGE_FILES, 1,
91      ac_cv_sys_large_files,
92      [Define for large files, on AIX-style hosts.],
93      [_AC_SYS_LARGEFILE_TEST_INCLUDES])
94  fi
95
96  AH_VERBATIM([_DARWIN_USE_64_BIT_INODE],
97[/* Enable large inode numbers on Mac OS X.  */
98#ifndef _DARWIN_USE_64_BIT_INODE
99# define _DARWIN_USE_64_BIT_INODE 1
100#endif])
101fi
102])# AC_SYS_LARGEFILE
103
104])# m4_version_prereq 2.69
105
106# Enable large files on systems where this is implemented by Gnulib, not by the
107# system headers.
108# Set the variables WINDOWS_64_BIT_OFF_T, WINDOWS_64_BIT_ST_SIZE if Gnulib
109# overrides ensure that off_t or 'struct size.st_size' are 64-bit, respectively.
110AC_DEFUN([gl_LARGEFILE],
111[
112  AC_REQUIRE([AC_CANONICAL_HOST])
113  case "$host_os" in
114    mingw*)
115      dnl Native Windows.
116      dnl mingw64 defines off_t to a 64-bit type already, if
117      dnl _FILE_OFFSET_BITS=64, which is ensured by AC_SYS_LARGEFILE.
118      AC_CACHE_CHECK([for 64-bit off_t], [gl_cv_type_off_t_64],
119        [AC_COMPILE_IFELSE(
120           [AC_LANG_PROGRAM(
121              [[#include <sys/types.h>
122                int verify_off_t_size[sizeof (off_t) >= 8 ? 1 : -1];
123              ]],
124              [[]])],
125           [gl_cv_type_off_t_64=yes], [gl_cv_type_off_t_64=no])
126        ])
127      if test $gl_cv_type_off_t_64 = no; then
128        WINDOWS_64_BIT_OFF_T=1
129      else
130        WINDOWS_64_BIT_OFF_T=0
131      fi
132      dnl But all native Windows platforms (including mingw64) have a 32-bit
133      dnl st_size member in 'struct stat'.
134      WINDOWS_64_BIT_ST_SIZE=1
135      ;;
136    *)
137      dnl Nothing to do on gnulib's side.
138      dnl A 64-bit off_t is
139      dnl   - already the default on Mac OS X, FreeBSD, NetBSD, OpenBSD, IRIX,
140      dnl     OSF/1, Cygwin,
141      dnl   - enabled by _FILE_OFFSET_BITS=64 (ensured by AC_SYS_LARGEFILE) on
142      dnl     glibc, HP-UX, Solaris,
143      dnl   - enabled by _LARGE_FILES=1 (ensured by AC_SYS_LARGEFILE) on AIX,
144      dnl   - impossible to achieve on Minix 3.1.8.
145      WINDOWS_64_BIT_OFF_T=0
146      WINDOWS_64_BIT_ST_SIZE=0
147      ;;
148  esac
149])
150