1# Enable large files on systems where this is not the default.
2
3# Copyright 1992-1996, 1998-2013 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 <= 2.69;
9# AC_SYS_LARGEFILE does not configure for large inodes on Mac OS X 10.5,
10# or configures them incorrectly in some cases.
11m4_version_prereq([2.70], [] ,[
12
13# _AC_SYS_LARGEFILE_TEST_INCLUDES
14# -------------------------------
15m4_define([_AC_SYS_LARGEFILE_TEST_INCLUDES],
16[@%:@include <sys/types.h>
17 /* Check that off_t can represent 2**63 - 1 correctly.
18    We can't simply define LARGE_OFF_T to be 9223372036854775807,
19    since some C++ compilers masquerading as C compilers
20    incorrectly reject 9223372036854775807.  */
21@%:@define LARGE_OFF_T (((off_t) 1 << 62) - 1 + ((off_t) 1 << 62))
22  int off_t_is_large[[(LARGE_OFF_T % 2147483629 == 721
23                       && LARGE_OFF_T % 2147483647 == 1)
24                      ? 1 : -1]];[]dnl
25])
26
27
28# _AC_SYS_LARGEFILE_MACRO_VALUE(C-MACRO, VALUE,
29#                               CACHE-VAR,
30#                               DESCRIPTION,
31#                               PROLOGUE, [FUNCTION-BODY])
32# --------------------------------------------------------
33m4_define([_AC_SYS_LARGEFILE_MACRO_VALUE],
34[AC_CACHE_CHECK([for $1 value needed for large files], [$3],
35[while :; do
36  m4_ifval([$6], [AC_LINK_IFELSE], [AC_COMPILE_IFELSE])(
37    [AC_LANG_PROGRAM([$5], [$6])],
38    [$3=no; break])
39  m4_ifval([$6], [AC_LINK_IFELSE], [AC_COMPILE_IFELSE])(
40    [AC_LANG_PROGRAM([@%:@define $1 $2
41$5], [$6])],
42    [$3=$2; break])
43  $3=unknown
44  break
45done])
46case $$3 in #(
47  no | unknown) ;;
48  *) AC_DEFINE_UNQUOTED([$1], [$$3], [$4]);;
49esac
50rm -rf conftest*[]dnl
51])# _AC_SYS_LARGEFILE_MACRO_VALUE
52
53
54# AC_SYS_LARGEFILE
55# ----------------
56# By default, many hosts won't let programs access large files;
57# one must use special compiler options to get large-file access to work.
58# For more details about this brain damage please see:
59# http://www.unix-systems.org/version2/whatsnew/lfs20mar.html
60AC_DEFUN([AC_SYS_LARGEFILE],
61[AC_ARG_ENABLE(largefile,
62               [  --disable-largefile     omit support for large files])
63if test "$enable_largefile" != no; then
64
65  AC_CACHE_CHECK([for special C compiler options needed for large files],
66    ac_cv_sys_largefile_CC,
67    [ac_cv_sys_largefile_CC=no
68     if test "$GCC" != yes; then
69       ac_save_CC=$CC
70       while :; do
71         # IRIX 6.2 and later do not support large files by default,
72         # so use the C compiler's -n32 option if that helps.
73         AC_LANG_CONFTEST([AC_LANG_PROGRAM([_AC_SYS_LARGEFILE_TEST_INCLUDES])])
74         AC_COMPILE_IFELSE([], [break])
75         CC="$CC -n32"
76         AC_COMPILE_IFELSE([], [ac_cv_sys_largefile_CC=' -n32'; break])
77         break
78       done
79       CC=$ac_save_CC
80       rm -f conftest.$ac_ext
81    fi])
82  if test "$ac_cv_sys_largefile_CC" != no; then
83    CC=$CC$ac_cv_sys_largefile_CC
84  fi
85
86  _AC_SYS_LARGEFILE_MACRO_VALUE(_FILE_OFFSET_BITS, 64,
87    ac_cv_sys_file_offset_bits,
88    [Number of bits in a file offset, on hosts where this is settable.],
89    [_AC_SYS_LARGEFILE_TEST_INCLUDES])
90  if test $ac_cv_sys_file_offset_bits = unknown; then
91    _AC_SYS_LARGEFILE_MACRO_VALUE(_LARGE_FILES, 1,
92      ac_cv_sys_large_files,
93      [Define for large files, on AIX-style hosts.],
94      [_AC_SYS_LARGEFILE_TEST_INCLUDES])
95  fi
96
97  AC_DEFINE([_DARWIN_USE_64_BIT_INODE], [1],
98    [Enable large inode numbers on Mac OS X 10.5.])
99fi
100])# AC_SYS_LARGEFILE
101])# m4_version_prereq 2.70
102
103# Enable large files on systems where this is implemented by Gnulib, not by the
104# system headers.
105# Set the variables WINDOWS_64_BIT_OFF_T, WINDOWS_64_BIT_ST_SIZE if Gnulib
106# overrides ensure that off_t or 'struct size.st_size' are 64-bit, respectively.
107AC_DEFUN([gl_LARGEFILE],
108[
109  AC_REQUIRE([AC_CANONICAL_HOST])
110  case "$host_os" in
111    mingw*)
112      dnl Native Windows.
113      dnl mingw64 defines off_t to a 64-bit type already, if
114      dnl _FILE_OFFSET_BITS=64, which is ensured by AC_SYS_LARGEFILE.
115      AC_CACHE_CHECK([for 64-bit off_t], [gl_cv_type_off_t_64],
116        [AC_COMPILE_IFELSE(
117           [AC_LANG_PROGRAM(
118              [[#include <sys/types.h>
119                int verify_off_t_size[sizeof (off_t) >= 8 ? 1 : -1];
120              ]],
121              [[]])],
122           [gl_cv_type_off_t_64=yes], [gl_cv_type_off_t_64=no])
123        ])
124      if test $gl_cv_type_off_t_64 = no; then
125        WINDOWS_64_BIT_OFF_T=1
126      else
127        WINDOWS_64_BIT_OFF_T=0
128      fi
129      dnl But all native Windows platforms (including mingw64) have a 32-bit
130      dnl st_size member in 'struct stat'.
131      WINDOWS_64_BIT_ST_SIZE=1
132      ;;
133    *)
134      dnl Nothing to do on gnulib's side.
135      dnl A 64-bit off_t is
136      dnl   - already the default on Mac OS X, FreeBSD, NetBSD, OpenBSD, IRIX,
137      dnl     OSF/1, Cygwin,
138      dnl   - enabled by _FILE_OFFSET_BITS=64 (ensured by AC_SYS_LARGEFILE) on
139      dnl     glibc, HP-UX, Solaris,
140      dnl   - enabled by _LARGE_FILES=1 (ensured by AC_SYS_LARGEFILE) on AIX,
141      dnl   - impossible to achieve on Minix 3.1.8.
142      WINDOWS_64_BIT_OFF_T=0
143      WINDOWS_64_BIT_ST_SIZE=0
144      ;;
145  esac
146])
147