xref: /netbsd-src/external/gpl3/gdb/dist/gnulib/import/m4/fdopendir.m4 (revision a8c74629f602faa0ccf8a463757d7baf858bbf3a)
1# serial 12
2# See if we need to provide fdopendir.
3
4dnl Copyright (C) 2009-2020 Free Software Foundation, Inc.
5dnl This file is free software; the Free Software Foundation
6dnl gives unlimited permission to copy and/or distribute it,
7dnl with or without modifications, as long as this notice is preserved.
8
9# Written by Eric Blake.
10
11AC_DEFUN([gl_FUNC_FDOPENDIR],
12[
13  AC_REQUIRE([gl_DIRENT_H_DEFAULTS])
14  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
15
16  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
17
18  dnl FreeBSD 7.3 has the function, but failed to declare it.
19  AC_CHECK_DECLS([fdopendir], [], [HAVE_DECL_FDOPENDIR=0], [[
20#include <dirent.h>
21    ]])
22  AC_CHECK_FUNCS_ONCE([fdopendir])
23  if test $ac_cv_func_fdopendir = no; then
24    HAVE_FDOPENDIR=0
25  else
26    AC_CACHE_CHECK([whether fdopendir works],
27      [gl_cv_func_fdopendir_works],
28      [AC_RUN_IFELSE([AC_LANG_PROGRAM([[
29#include <dirent.h>
30#include <fcntl.h>
31#include <unistd.h>
32#if !HAVE_DECL_FDOPENDIR
33extern
34# ifdef __cplusplus
35"C"
36# endif
37DIR *fdopendir (int);
38#endif
39]], [int result = 0;
40     int fd = open ("conftest.c", O_RDONLY);
41     if (fd < 0) result |= 1;
42     if (fdopendir (fd)) result |= 2;
43     if (close (fd)) result |= 4;
44     return result;])],
45         [gl_cv_func_fdopendir_works=yes],
46         [gl_cv_func_fdopendir_works=no],
47         [case "$host_os" in
48                     # Guess yes on glibc systems.
49            *-gnu*)  gl_cv_func_fdopendir_works="guessing yes" ;;
50                     # Guess yes on musl systems.
51            *-musl*) gl_cv_func_fdopendir_works="guessing yes" ;;
52                     # Guess yes on bsd.
53            *bsd*)   gl_cv_func_fdopendir_works="guessing yes" ;;
54                     # If we don't know, obey --enable-cross-guesses.
55            *)       gl_cv_func_fdopendir_works="$gl_cross_guess_normal" ;;
56          esac
57         ])])
58    case "$gl_cv_func_fdopendir_works" in
59      *yes) ;;
60      *)
61        REPLACE_FDOPENDIR=1
62        ;;
63    esac
64  fi
65])
66