# Enable large files on systems where this is not the default.

# Enable support for files on Linux file systems with 64-bit inode numbers.

# Copyright 1992-1996, 1998-2020 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 macro works around a problem in Autoconf's AC_FUNC_FSEEKO:

# It does not set _LARGEFILE_SOURCE=1 on HP-UX/ia64 32-bit, although this

# setting of _LARGEFILE_SOURCE is needed so that <stdio.h> declares fseeko

# and ftello in C++ mode as well.

AC_DEFUN([gl_SET_LARGEFILE_SOURCE],

[

  AC_REQUIRE([AC_CANONICAL_HOST])

  AC_FUNC_FSEEKO

  case "$host_os" in

    hpux*)

      AC_DEFINE([_LARGEFILE_SOURCE], [1],

        [Define to 1 to make fseeko visible on some hosts (e.g. glibc 2.2).])

      ;;

  esac

])

# 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

# -------------------------------

m4_define([_AC_SYS_LARGEFILE_TEST_INCLUDES],

[@%:@include <sys/types.h>

 /* Check that off_t can represent 2**63 - 1 correctly.

    We can't simply define LARGE_OFF_T to be 9223372036854775807,

    since some C++ compilers masquerading as C compilers

    incorrectly reject 9223372036854775807.  */

@%:@define LARGE_OFF_T (((off_t) 1 << 62) - 1 + ((off_t) 1 << 62))

  int off_t_is_large[[(LARGE_OFF_T % 2147483629 == 721

                       && LARGE_OFF_T % 2147483647 == 1)

                      ? 1 : -1]];[]dnl

])

# _AC_SYS_LARGEFILE_MACRO_VALUE(C-MACRO, VALUE,

#                               CACHE-VAR,

#                               DESCRIPTION,

#                               PROLOGUE, [FUNCTION-BODY])

# --------------------------------------------------------

m4_define([_AC_SYS_LARGEFILE_MACRO_VALUE],

[AC_CACHE_CHECK([for $1 value needed for large files], [$3],

[while :; do

  m4_ifval([$6], [AC_LINK_IFELSE], [AC_COMPILE_IFELSE])(

    [AC_LANG_PROGRAM([$5], [$6])],

    [$3=no; break])

  m4_ifval([$6], [AC_LINK_IFELSE], [AC_COMPILE_IFELSE])(

    [AC_LANG_PROGRAM([@%:@define $1 $2

$5], [$6])],

    [$3=$2; break])

  $3=unknown

  break

done])

case $$3 in #(

  no | unknown) ;;

  *) AC_DEFINE_UNQUOTED([$1], [$$3], [$4]);;

esac

rm -rf conftest*[]dnl

])# _AC_SYS_LARGEFILE_MACRO_VALUE

# AC_SYS_LARGEFILE

# ----------------

# By default, many hosts won't let programs access large files;

# one must use special compiler options to get large-file access to work.

# For more details about this brain damage please see:

# http://www.unix.org/version2/whatsnew/lfs20mar.html

# Additionally, on Linux file systems with 64-bit inodes a file that happens

# to have a 64-bit inode number cannot be accessed by 32-bit applications on

# Linux x86/x86_64.  This can occur with file systems such as XFS and NFS.

AC_DEFUN([AC_SYS_LARGEFILE],

[AC_ARG_ENABLE(largefile,

               [  --disable-largefile     omit support for large files])

if test "$enable_largefile" != no; then

  AC_CACHE_CHECK([for special C compiler options needed for large files],

    ac_cv_sys_largefile_CC,

    [ac_cv_sys_largefile_CC=no

     if test "$GCC" != yes; then

       ac_save_CC=$CC

       while :; do

         # IRIX 6.2 and later do not support large files by default,

         # so use the C compiler's -n32 option if that helps.

         AC_LANG_CONFTEST([AC_LANG_PROGRAM([_AC_SYS_LARGEFILE_TEST_INCLUDES])])

         AC_COMPILE_IFELSE([], [break])

         CC="$CC -n32"

         AC_COMPILE_IFELSE([], [ac_cv_sys_largefile_CC=' -n32'; break])

         break

       done

       CC=$ac_save_CC

       rm -f conftest.$ac_ext

    fi])

  if test "$ac_cv_sys_largefile_CC" != no; then

    CC=$CC$ac_cv_sys_largefile_CC

  fi

  _AC_SYS_LARGEFILE_MACRO_VALUE(_FILE_OFFSET_BITS, 64,

    ac_cv_sys_file_offset_bits,

    [Number of bits in a file offset, on hosts where this is settable.],

    [_AC_SYS_LARGEFILE_TEST_INCLUDES])

  if test $ac_cv_sys_file_offset_bits = unknown; then

    _AC_SYS_LARGEFILE_MACRO_VALUE(_LARGE_FILES, 1,

      ac_cv_sys_large_files,

      [Define for large files, on AIX-style hosts.],

      [_AC_SYS_LARGEFILE_TEST_INCLUDES])

  fi

fi

])# AC_SYS_LARGEFILE

])# m4_version_prereq 2.70

# 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 Some mingw versions define, if _FILE_OFFSET_BITS=64, 'struct stat'

      dnl to 'struct _stat32i64' or 'struct _stat64' (depending on

      dnl _USE_32BIT_TIME_T), which has a 32-bit st_size member.

      AC_CACHE_CHECK([for 64-bit st_size], [gl_cv_member_st_size_64],

        [AC_COMPILE_IFELSE(

           [AC_LANG_PROGRAM(

              [[#include <sys/types.h>

                struct stat buf;

                int verify_st_size_size[sizeof (buf.st_size) >= 8 ? 1 : -1];

              ]],

              [[]])],

           [gl_cv_member_st_size_64=yes], [gl_cv_member_st_size_64=no])

        ])

      if test $gl_cv_member_st_size_64 = no; then

        WINDOWS_64_BIT_ST_SIZE=1

      else

        WINDOWS_64_BIT_ST_SIZE=0

      fi

      ;;

    *)

      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

])