d901c3f18e2a11286d222482de795a14270a29a1
[gnulib.git] / m4 / sys_socket_h.m4
1 # sys_socket_h.m4 serial 7
2 dnl Copyright (C) 2005-2008 Free Software Foundation, Inc.
3 dnl This file is free software; the Free Software Foundation
4 dnl gives unlimited permission to copy and/or distribute it,
5 dnl with or without modifications, as long as this notice is preserved.
6
7 dnl From Simon Josefsson.
8
9 AC_DEFUN([gl_HEADER_SYS_SOCKET],
10 [
11   AC_REQUIRE([AC_C_INLINE])
12
13   AC_CACHE_CHECK([whether <sys/socket.h> is self-contained],
14     [gl_cv_header_sys_socket_h_selfcontained],
15     [
16       AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <sys/socket.h>]], [[]])],
17         [gl_cv_header_sys_socket_h_selfcontained=yes],
18         [gl_cv_header_sys_socket_h_selfcontained=no])
19     ])
20   if test $gl_cv_header_sys_socket_h_selfcontained = yes; then
21     SYS_SOCKET_H=''
22     dnl If the shutdown function exists, <sys/socket.h> should define
23     dnl SHUT_RD, SHUT_WR, SHUT_RDWR.
24     AC_CHECK_FUNCS([shutdown])
25     if test $ac_cv_func_shutdown = yes; then
26       AC_CACHE_CHECK([whether <sys/socket.h> defines the SHUT_* macros],
27         [gl_cv_header_sys_socket_h_shut],
28         [
29           AC_COMPILE_IFELSE(
30             [AC_LANG_PROGRAM([[#include <sys/socket.h>]],
31                [[int a[] = { SHUT_RD, SHUT_WR, SHUT_RDWR };]])],
32             [gl_cv_header_sys_socket_h_shut=yes],
33             [gl_cv_header_sys_socket_h_shut=no])
34         ])
35       if test $gl_cv_header_sys_socket_h_shut = no; then
36         SYS_SOCKET_H='sys/socket.h'
37       fi
38     fi
39   else
40     SYS_SOCKET_H='sys/socket.h'
41   fi
42   if test -n "$SYS_SOCKET_H"; then
43     dnl Check prerequisites of the <sys/socket.h> replacement.
44     gl_CHECK_NEXT_HEADERS([sys/socket.h])
45     if test $ac_cv_header_sys_socket_h = yes; then
46       HAVE_SYS_SOCKET_H=1
47       HAVE_WS2TCPIP_H=0
48     else
49       HAVE_SYS_SOCKET_H=0
50       dnl We cannot use AC_CHECK_HEADERS_ONCE here, because that would make
51       dnl the check for those headers unconditional; yet cygwin reports
52       dnl that the headers are present but cannot be compiled (since on
53       dnl cygwin, all socket information should come from sys/socket.h).
54       AC_CHECK_HEADERS([ws2tcpip.h])
55       if test $ac_cv_header_ws2tcpip_h = yes; then
56         HAVE_WS2TCPIP_H=1
57       else
58         HAVE_WS2TCPIP_H=0
59       fi
60     fi
61     gl_PREREQ_SYS_H_WINSOCK2
62     if test x$ac_cv_header_winsock2_h = xyes; then
63       AC_LIBOBJ(winsock)
64     fi
65     AC_SUBST([HAVE_SYS_SOCKET_H])
66     AC_SUBST([HAVE_WS2TCPIP_H])
67   fi
68   AC_SUBST([SYS_SOCKET_H])
69 ])
70
71 # Common prerequisites of of the <sys/socket.h> replacement and of the
72 # <sys/select.h> replacement.
73 # Sets and substitutes HAVE_WINSOCK2_H.
74 AC_DEFUN([gl_PREREQ_SYS_H_WINSOCK2],
75 [
76   AC_CHECK_HEADERS_ONCE([sys/socket.h])
77   if test $ac_cv_header_sys_socket_h != yes; then
78     dnl We cannot use AC_CHECK_HEADERS_ONCE here, because that would make
79     dnl the check for those headers unconditional; yet cygwin reports
80     dnl that the headers are present but cannot be compiled (since on
81     dnl cygwin, all socket information should come from sys/socket.h).
82     AC_CHECK_HEADERS([winsock2.h])
83   fi
84   if test "$ac_cv_header_winsock2_h" = yes; then
85     HAVE_WINSOCK2_H=1
86   else
87     HAVE_WINSOCK2_H=0
88   fi
89   AC_SUBST([HAVE_WINSOCK2_H])
90 ])