fdopendir.m4 1.83 KB
Newer Older
Paul Eggert's avatar
Paul Eggert committed
1
# serial 12
2 3
# See if we need to provide fdopendir.

Paul Eggert's avatar
Paul Eggert committed
4
dnl Copyright (C) 2009-2020 Free Software Foundation, Inc.
5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.

# Written by Eric Blake.

AC_DEFUN([gl_FUNC_FDOPENDIR],
[
  AC_REQUIRE([gl_DIRENT_H_DEFAULTS])
  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles

  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])

  dnl FreeBSD 7.3 has the function, but failed to declare it.
  AC_CHECK_DECLS([fdopendir], [], [HAVE_DECL_FDOPENDIR=0], [[
#include <dirent.h>
    ]])
  AC_CHECK_FUNCS_ONCE([fdopendir])
  if test $ac_cv_func_fdopendir = no; then
    HAVE_FDOPENDIR=0
  else
    AC_CACHE_CHECK([whether fdopendir works],
      [gl_cv_func_fdopendir_works],
      [AC_RUN_IFELSE([AC_LANG_PROGRAM([[
#include <dirent.h>
#include <fcntl.h>
#include <unistd.h>
#if !HAVE_DECL_FDOPENDIR
extern
# ifdef __cplusplus
"C"
# endif
DIR *fdopendir (int);
#endif
]], [int result = 0;
     int fd = open ("conftest.c", O_RDONLY);
     if (fd < 0) result |= 1;
     if (fdopendir (fd)) result |= 2;
     if (close (fd)) result |= 4;
     return result;])],
         [gl_cv_func_fdopendir_works=yes],
         [gl_cv_func_fdopendir_works=no],
         [case "$host_os" in
Paul Eggert's avatar
Paul Eggert committed
48 49 50 51
                     # Guess yes on glibc systems.
            *-gnu*)  gl_cv_func_fdopendir_works="guessing yes" ;;
                     # Guess yes on musl systems.
            *-musl*) gl_cv_func_fdopendir_works="guessing yes" ;;
Paul Eggert's avatar
Paul Eggert committed
52 53
                     # If we don't know, obey --enable-cross-guesses.
            *)       gl_cv_func_fdopendir_works="$gl_cross_guess_normal" ;;
54 55 56 57 58 59 60 61 62 63
          esac
         ])])
    case "$gl_cv_func_fdopendir_works" in
      *yes) ;;
      *)
        REPLACE_FDOPENDIR=1
        ;;
    esac
  fi
])