curl/acinclude.m4

#***************************************************************************
#                                  _   _ ____  _
#  Project                     ___| | | |  _ \| |
#                             / __| | | | |_) | |
#                            | (__| |_| |  _ <| |___
#                             \___|\___/|_| \_\_____|
#
# Copyright (C) 1998 - 2005, Daniel Stenberg, <daniel@haxx.se>, et al.
#
# This software is licensed as described in the file COPYING, which
# you should have received as part of this distribution. The terms
# are also available at http://curl.haxx.se/docs/copyright.html.
#
# You may opt to use, copy, modify, merge, publish, distribute and/or sell
# copies of the Software, and permit persons to whom the Software is
# furnished to do so, under the terms of the COPYING file.
#
# This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
# KIND, either express or implied.
#
# $Id$
###########################################################################

dnl CURL_CHECK_HEADER_WINDOWS
dnl -------------------------------------------------
dnl Check for compilable and valid windows.h header 

AC_DEFUN([CURL_CHECK_HEADER_WINDOWS], [
  AC_CACHE_CHECK([for windows.h], [ac_cv_header_windows_h], [
    AC_COMPILE_IFELSE([
      AC_LANG_PROGRAM([
#undef inline
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#include <windows.h>
      ],[
        int dummy=2*WINVER;
      ])
    ],[
      ac_cv_header_windows_h="yes"
    ],[
      ac_cv_header_windows_h="no"
    ])
  ])
  if test "x$ac_cv_header_windows_h" = "xyes"; then
    AC_DEFINE_UNQUOTED(HAVE_WINDOWS_H, 1,
      [Define to 1 if you have the windows.h header file.])
    AC_DEFINE_UNQUOTED(WIN32_LEAN_AND_MEAN, 1,
      [Define to avoid automatic inclusion of winsock.h])
  fi
])


dnl CURL_CHECK_HEADER_WINSOCK
dnl -------------------------------------------------
dnl Check for compilable and valid winsock.h header 

AC_DEFUN([CURL_CHECK_HEADER_WINSOCK], [
  AC_REQUIRE([CURL_CHECK_HEADER_WINDOWS])dnl
  AC_CACHE_CHECK([for winsock.h], [ac_cv_header_winsock_h], [
    AC_COMPILE_IFELSE([
      AC_LANG_PROGRAM([
#undef inline
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#include <windows.h>
#include <winsock.h>
      ],[
        int dummy=WSACleanup();
      ])
    ],[
      ac_cv_header_winsock_h="yes"
    ],[
      ac_cv_header_winsock_h="no"
    ])
  ])
  if test "x$ac_cv_header_winsock_h" = "xyes"; then
    AC_DEFINE_UNQUOTED(HAVE_WINSOCK_H, 1,
      [Define to 1 if you have the winsock.h header file.])
  fi
])


dnl CURL_CHECK_HEADER_WINSOCK2
dnl -------------------------------------------------
dnl Check for compilable and valid winsock2.h header 

AC_DEFUN([CURL_CHECK_HEADER_WINSOCK2], [
  AC_REQUIRE([CURL_CHECK_HEADER_WINDOWS])dnl
  AC_CACHE_CHECK([for winsock2.h], [ac_cv_header_winsock2_h], [
    AC_COMPILE_IFELSE([
      AC_LANG_PROGRAM([
#undef inline
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#include <windows.h>
#include <winsock2.h>
      ],[
        int dummy=2*IPPROTO_ESP;
      ])
    ],[
      ac_cv_header_winsock2_h="yes"
    ],[
      ac_cv_header_winsock2_h="no"
    ])
  ])
  if test "x$ac_cv_header_winsock2_h" = "xyes"; then
    AC_DEFINE_UNQUOTED(HAVE_WINSOCK2_H, 1,
      [Define to 1 if you have the winsock2.h header file.])
  fi
])


dnl CURL_CHECK_HEADER_WS2TCPIP
dnl -------------------------------------------------
dnl Check for compilable and valid ws2tcpip.h header

AC_DEFUN([CURL_CHECK_HEADER_WS2TCPIP], [
  AC_REQUIRE([CURL_CHECK_HEADER_WINSOCK2])dnl
  AC_CACHE_CHECK([for ws2tcpip.h], [ac_cv_header_ws2tcpip_h], [
    AC_COMPILE_IFELSE([
      AC_LANG_PROGRAM([
#undef inline
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#include <windows.h>
#include <winsock2.h>
#include <ws2tcpip.h>
      ],[
        int dummy=2*IP_PKTINFO;
      ])
    ],[
      ac_cv_header_ws2tcpip_h="yes"
    ],[
      ac_cv_header_ws2tcpip_h="no"
    ])
  ])
  if test "x$ac_cv_header_ws2tcpip_h" = "xyes"; then
    AC_DEFINE_UNQUOTED(HAVE_WS2TCPIP_H, 1,
      [Define to 1 if you have the ws2tcpip.h header file.])
  fi
])


dnl CURL_CHECK_TYPE_SOCKLEN_T
dnl -------------------------------------------------
dnl Check for existing socklen_t type, and provide
dnl an equivalent type if socklen_t not available

AC_DEFUN([CURL_CHECK_TYPE_SOCKLEN_T], [
  AC_REQUIRE([CURL_CHECK_HEADER_WS2TCPIP])dnl
  AC_CHECK_TYPE([socklen_t], ,[
    AC_CACHE_CHECK([for socklen_t equivalent], 
      [curl_cv_socklen_t_equiv], [
      curl_cv_socklen_t_equiv="unknown"
      for arg2 in "struct sockaddr" void; do
        for t in int size_t unsigned long "unsigned long"; do
          AC_COMPILE_IFELSE([
            AC_LANG_PROGRAM([
#undef inline
#ifdef HAVE_WINDOWS_H
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#include <windows.h>
#ifdef HAVE_WINSOCK2_H
#include <winsock2.h>
#else
#ifdef HAVE_WINSOCK_H
#include <winsock.h>
#endif
#endif
#else
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#endif
              int getpeername (int, $arg2 *, $t *);
            ],[
              $t len=0;
              getpeername(0,0,&len);
            ])
          ],[
             curl_cv_socklen_t_equiv="$t"
             break 2
          ])
        done
      done
    ])
    if test "$curl_cv_socklen_t_equiv" = "unknown"; then
      AC_MSG_ERROR([Cannot find a type to use in place of socklen_t])
    else
      AC_DEFINE_UNQUOTED(socklen_t, $curl_cv_socklen_t_equiv,
        [type to use in place of socklen_t if not defined])
    fi
  ],[
#undef inline
#ifdef HAVE_WINDOWS_H
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#include <windows.h>
#ifdef HAVE_WINSOCK2_H
#include <winsock2.h>
#ifdef HAVE_WS2TCPIP_H
#include <ws2tcpip.h>
#endif
#endif
#else
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#endif
  ])
])


dnl CURL_CHECK_FUNC_GETNAMEINFO
dnl -------------------------------------------------
dnl Test if the getnameinfo function is available, 
dnl and check the types of five of its arguments.
dnl If the function succeeds HAVE_GETNAMEINFO will be
dnl defined, defining the types of the arguments in
dnl GETNAMEINFO_TYPE_ARG1, GETNAMEINFO_TYPE_ARG2,
dnl GETNAMEINFO_TYPE_ARG46 and GETNAMEINFO_TYPE_ARG7.
dnl This function is experimental and its results shall
dnl not be trusted while this notice is in place ------

AC_DEFUN([CURL_CHECK_FUNC_GETNAMEINFO], [
  AC_REQUIRE([CURL_CHECK_HEADER_WS2TCPIP])dnl
  AC_REQUIRE([CURL_CHECK_TYPE_SOCKLEN_T])dnl
  AC_CHECK_HEADERS(sys/types.h sys/socket.h netdb.h)
  #
  AC_MSG_CHECKING([for getnameinfo])
  AC_LINK_IFELSE([
      AC_LANG_FUNC_LINK_TRY([getnameinfo])
    ],[
      AC_MSG_RESULT([yes])
      curl_cv_getnameinfo="yes"
    ],[
      AC_MSG_RESULT([no])
      curl_cv_getnameinfo="no"
  ])
  #
  if test "$curl_cv_getnameinfo" != "yes"; then
    AC_MSG_CHECKING([deeper for getnameinfo])
    AC_TRY_LINK([
      ],[
        getnameinfo();
      ],[
        AC_MSG_RESULT([yes])
        curl_cv_getnameinfo="yes"
      ],[
        AC_MSG_RESULT([but still no])
        curl_cv_getnameinfo="no"
    ])
  fi
  #
  if test "$curl_cv_getnameinfo" != "yes"; then
    AC_MSG_CHECKING([deeper and deeper for getnameinfo])
    AC_TRY_LINK([
#undef inline
#ifdef HAVE_WINDOWS_H
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#include <windows.h>
#ifdef HAVE_WINSOCK2_H
#include <winsock2.h>
#ifdef HAVE_WS2TCPIP_H
#include <ws2tcpip.h>
#endif
#endif
#else
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#ifdef HAVE_NETDB_H
#include <netdb.h>
#endif
#endif
      ],[
        getnameinfo(0, 0, 0, 0, 0, 0, 0);
      ],[ 
        AC_MSG_RESULT([yes])
        curl_cv_getnameinfo="yes"
      ],[
        AC_MSG_RESULT([but still no])
        curl_cv_getnameinfo="no"
    ])
  fi
  #
  if test "$curl_cv_getnameinfo" = "yes"; then
    AC_CACHE_CHECK([types of arguments for getnameinfo],
      [curl_cv_func_getnameinfo_args], [
      curl_cv_func_getnameinfo_args="unknown"
      for gni_arg1 in 'struct sockaddr *' 'const struct sockaddr *' 'void *'; do
        for gni_arg2 in 'socklen_t' 'size_t' 'int'; do
          for gni_arg46 in 'size_t' 'int' 'socklen_t' 'unsigned int' 'DWORD'; do
            for gni_arg7 in 'int' 'unsigned int'; do
              AC_COMPILE_IFELSE([
                AC_LANG_PROGRAM([
#undef inline 
#ifdef HAVE_WINDOWS_H
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#if (!defined(_WIN32_WINNT)) || (_WIN32_WINNT < 0x0501)
#undef _WIN32_WINNT
#define _WIN32_WINNT 0x0501
#endif
#include <windows.h>
#ifdef HAVE_WINSOCK2_H
#include <winsock2.h> 
#ifdef HAVE_WS2TCPIP_H
#include <ws2tcpip.h>
#endif
#endif
#define GNICALLCONV WSAAPI
#else
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#ifdef HAVE_NETDB_H
#include <netdb.h>
#endif
#define GNICALLCONV
#endif
                  extern int GNICALLCONV getnameinfo($gni_arg1, $gni_arg2,
                                         char *, $gni_arg46,
                                         char *, $gni_arg46,
                                         $gni_arg7);
                ],[
                  $gni_arg2 salen=0;
                  $gni_arg46 hostlen=0;
                  $gni_arg46 servlen=0;
                  $gni_arg7 flags=0;
                  int res = getnameinfo(0, salen, 0, hostlen, 0, servlen, flags);
                ])
              ],[
                 curl_cv_func_getnameinfo_args="$gni_arg1,$gni_arg2,$gni_arg46,$gni_arg7"
                 break 4
              ])
            done
          done
        done
      done
    ]) # AC_CACHE_CHECK
    if test "$curl_cv_func_getnameinfo_args" = "unknown"; then
      AC_MSG_WARN([Cannot find proper types to use for getnameinfo args])
      AC_MSG_WARN([HAVE_GETNAMEINFO will not be defined])
    else
      gni_prev_IFS=$IFS; IFS=','
      set dummy `echo "$curl_cv_func_getnameinfo_args" | sed 's/\*/\*/g'`
      IFS=$gni_prev_IFS
      shift
      AC_DEFINE_UNQUOTED(GETNAMEINFO_TYPE_ARG1, $[1],
        [Define to the type of arg 1 for getnameinfo.])
      AC_DEFINE_UNQUOTED(GETNAMEINFO_TYPE_ARG2, $[2],
        [Define to the type of arg 2 for getnameinfo.])
      AC_DEFINE_UNQUOTED(GETNAMEINFO_TYPE_ARG46, $[3],
        [Define to the type of args 4 and 6 for getnameinfo.])
      AC_DEFINE_UNQUOTED(GETNAMEINFO_TYPE_ARG7, $[4],
        [Define to the type of arg 7 for getnameinfo.])
      AC_DEFINE_UNQUOTED(HAVE_GETNAMEINFO, 1,
        [Define to 1 if you have the getnameinfo function.])
      ac_cv_func_getnameinfo="yes"
    fi
  fi
]) # AC_DEFUN


dnl CURL_CHECK_NONBLOCKING_SOCKET
dnl -------------------------------------------------
dnl Check for how to set a socket to non-blocking state. There seems to exist
dnl four known different ways, with the one used almost everywhere being POSIX
dnl and XPG3, while the other different ways for different systems (old BSD,
dnl Windows and Amiga).
dnl
dnl There are two known platforms (AIX 3.x and SunOS 4.1.x) where the
dnl O_NONBLOCK define is found but does not work. This condition is attempted
dnl to get caught in this script by using an excessive number of #ifdefs...
dnl
AC_DEFUN([CURL_CHECK_NONBLOCKING_SOCKET],
[
  AC_MSG_CHECKING([non-blocking sockets style])

  AC_TRY_COMPILE([
/* headers for O_NONBLOCK test */
#include <sys/types.h>
#include <unistd.h>
#include <fcntl.h>
],[
/* try to compile O_NONBLOCK */

#if defined(sun) || defined(__sun__) || defined(__SUNPRO_C) || defined(__SUNPRO_CC)
# if defined(__SVR4) || defined(__srv4__)
#  define PLATFORM_SOLARIS
# else
#  define PLATFORM_SUNOS4
# endif
#endif
#if (defined(_AIX) || defined(__xlC__)) && !defined(_AIX4)
# define PLATFORM_AIX_V3
#endif

#if defined(PLATFORM_SUNOS4) || defined(PLATFORM_AIX_V3) || defined(__BEOS__)
#error "O_NONBLOCK does not work on this platform"
#endif
  int socket;
  int flags = fcntl(socket, F_SETFL, flags | O_NONBLOCK);
],[
dnl the O_NONBLOCK test was fine
nonblock="O_NONBLOCK"
AC_DEFINE(HAVE_O_NONBLOCK, 1, [use O_NONBLOCK for non-blocking sockets])
],[
dnl the code was bad, try a different program now, test 2

  AC_TRY_COMPILE([
/* headers for FIONBIO test */
#include <unistd.h>
#include <stropts.h>
],[
/* FIONBIO source test (old-style unix) */
 int socket;
 int flags = ioctl(socket, FIONBIO, &flags);
],[
dnl FIONBIO test was good
nonblock="FIONBIO"
AC_DEFINE(HAVE_FIONBIO, 1, [use FIONBIO for non-blocking sockets])
],[
dnl FIONBIO test was also bad
dnl the code was bad, try a different program now, test 3

  AC_TRY_COMPILE([
/* headers for ioctlsocket test (Windows) */
#undef inline
#ifdef HAVE_WINDOWS_H
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#include <windows.h>
#ifdef HAVE_WINSOCK2_H
#include <winsock2.h>
#else
#ifdef HAVE_WINSOCK_H
#include <winsock.h>
#endif
#endif
#endif
],[
/* ioctlsocket source code */
 SOCKET sd;
 unsigned long flags = 0;
 sd = socket(0, 0, 0);
 ioctlsocket(sd, FIONBIO, &flags);
],[
dnl ioctlsocket test was good
nonblock="ioctlsocket"
AC_DEFINE(HAVE_IOCTLSOCKET, 1, [use ioctlsocket() for non-blocking sockets])
],[
dnl ioctlsocket didnt compile!, go to test 4

  AC_TRY_LINK([
/* headers for IoctlSocket test (Amiga?) */
#include <sys/ioctl.h>
],[
/* IoctlSocket source code */
 int socket;
 int flags = IoctlSocket(socket, FIONBIO, (long)1);
],[
dnl ioctlsocket test was good
nonblock="IoctlSocket"
AC_DEFINE(HAVE_IOCTLSOCKET_CASE, 1, [use Ioctlsocket() for non-blocking sockets])
],[
dnl Ioctlsocket didnt compile, do test 5!
  AC_TRY_COMPILE([
/* headers for SO_NONBLOCK test (BeOS) */
#include <socket.h>
],[
/* SO_NONBLOCK source code */
 long b = 1;
 int socket;
 int flags = setsockopt(socket, SOL_SOCKET, SO_NONBLOCK, &b, sizeof(b));
],[
dnl the SO_NONBLOCK test was good
nonblock="SO_NONBLOCK"
AC_DEFINE(HAVE_SO_NONBLOCK, 1, [use SO_NONBLOCK for non-blocking sockets])
],[
dnl test 5 didnt compile!
nonblock="nada"
AC_DEFINE(HAVE_DISABLED_NONBLOCKING, 1, [disabled non-blocking sockets])
])
dnl end of fifth test

])
dnl end of forth test

])
dnl end of third test

])
dnl end of second test

])
dnl end of non-blocking try-compile test
  AC_MSG_RESULT($nonblock)

  if test "$nonblock" = "nada"; then
    AC_MSG_WARN([non-block sockets disabled])
  fi
])


dnl TYPE_SOCKADDR_STORAGE
dnl -------------------------------------------------
dnl Check for struct sockaddr_storage. Most IPv6-enabled hosts have it, but
dnl AIX 4.3 is one known exception.
AC_DEFUN([TYPE_SOCKADDR_STORAGE],
[
   AC_CHECK_TYPE([struct sockaddr_storage],
        AC_DEFINE(HAVE_STRUCT_SOCKADDR_STORAGE, 1,
                  [if struct sockaddr_storage is defined]), ,
   [
#undef inline
#ifdef HAVE_WINDOWS_H
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#include <windows.h>
#ifdef HAVE_WINSOCK2_H
#include <winsock2.h>
#endif
#else
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#ifdef HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif
#endif
   ])
])


dnl TYPE_IN_ADDR_T
dnl -------------------------------------------------
dnl Check for in_addr_t: it is used to receive the return code of inet_addr()
dnl and a few other things.
AC_DEFUN([TYPE_IN_ADDR_T],
[
   AC_CHECK_TYPE([in_addr_t], ,[
      AC_MSG_CHECKING([for in_addr_t equivalent])
      AC_CACHE_VAL([curl_cv_in_addr_t_equiv],
      [
         curl_cv_in_addr_t_equiv=
         for t in "unsigned long" int size_t unsigned long; do
            AC_TRY_COMPILE([
#undef inline
#ifdef HAVE_WINDOWS_H
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#include <windows.h>
#ifdef HAVE_WINSOCK2_H
#include <winsock2.h>
#else
#ifdef HAVE_WINSOCK_H
#include <winsock.h>
#endif
#endif
#else
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#ifdef HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif
#endif
            ],[
               $t data = inet_addr ("1.2.3.4");
            ],[
               curl_cv_in_addr_t_equiv="$t"
               break
            ])
         done

         if test "x$curl_cv_in_addr_t_equiv" = x; then
            AC_MSG_ERROR([Cannot find a type to use in place of in_addr_t])
         fi
      ])
      AC_MSG_RESULT($curl_cv_in_addr_t_equiv)
      AC_DEFINE_UNQUOTED(in_addr_t, $curl_cv_in_addr_t_equiv,
			[type to use in place of in_addr_t if not defined])],
      [
#undef inline
#ifdef HAVE_WINDOWS_H
#ifndef WIN32_LEAN_AND_MEAN
#define WIN32_LEAN_AND_MEAN
#endif
#include <windows.h>
#ifdef HAVE_WINSOCK2_H
#include <winsock2.h>
#else
#ifdef HAVE_WINSOCK_H
#include <winsock.h>
#endif
#endif
#else
#ifdef HAVE_SYS_TYPES_H
#include <sys/types.h>
#endif
#ifdef HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#ifdef HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#ifdef HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif
#endif
  ]) dnl AC_CHECK_TYPE
]) dnl AC_DEFUN

dnl ************************************************************
dnl check for "localhost", if it doesn't exist, we can't do the
dnl gethostbyname_r tests!
dnl 

AC_DEFUN([CURL_CHECK_WORKING_RESOLVER],[
AC_MSG_CHECKING([if "localhost" resolves])
AC_TRY_RUN([
#include <string.h>
#include <sys/types.h>
#include <netdb.h>

int
main () {
struct hostent *h;
h = gethostbyname("localhost");
exit (h == NULL ? 1 : 0); }],[
      AC_MSG_RESULT(yes)],[
      AC_MSG_RESULT(no)
      AC_MSG_ERROR([can't figure out gethostbyname_r() since localhost doesn't resolve])

      ]
)
])

dnl ************************************************************
dnl check for working getaddrinfo() that works with AI_NUMERICHOST
dnl
AC_DEFUN([CURL_CHECK_WORKING_GETADDRINFO],[
  AC_CACHE_CHECK(for working getaddrinfo, ac_cv_working_getaddrinfo,[
  AC_TRY_RUN( [
#include <netdb.h>
#include <sys/types.h>
#include <sys/socket.h>

int main(void)
{
    struct addrinfo hints, *ai;
    int error;

    memset(&hints, 0, sizeof(hints));
    hints.ai_flags = AI_NUMERICHOST;
    hints.ai_family = AF_UNSPEC;
    hints.ai_socktype = SOCK_STREAM;
    error = getaddrinfo("127.0.0.1", "8080", &hints, &ai);
    if (error) {
        return 1;
    }
    return 0;
}
],[
  ac_cv_working_getaddrinfo="yes"
],[
  ac_cv_working_getaddrinfo="no"
],[
  ac_cv_working_getaddrinfo="yes"
])])
if test "$ac_cv_working_getaddrinfo" = "yes"; then
  AC_DEFINE(HAVE_GETADDRINFO, 1, [Define if getaddrinfo exists and works])
  AC_DEFINE(ENABLE_IPV6, 1, [Define if you want to enable IPv6 support])

  IPV6_ENABLED=1
  AC_SUBST(IPV6_ENABLED)
fi
])

dnl ************************************************************
dnl check for working NI_WITHSCOPEID in getnameinfo()
dnl
AC_DEFUN([CURL_CHECK_NI_WITHSCOPEID],[
  AC_CACHE_CHECK(for working NI_WITHSCOPEID, ac_cv_working_ni_withscopeid,[

 AC_RUN_IFELSE([[
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
int main()
{
#ifdef NI_WITHSCOPEID
   struct sockaddr_storage ss;
   int sslen = sizeof(ss);
   int rc;
   char hbuf[NI_MAXHOST];
   int fd = socket(AF_INET6, SOCK_STREAM, 0);
   if(fd < 0) {
     perror("socket()");
     return 1; /* couldn't create socket of either kind */
   }

   rc = getsockname(fd, (struct sockaddr *)&ss, &sslen);
   if(rc) {
     perror("getsockname()");
     return 2;
   }

   rc = getnameinfo((struct sockaddr *)&ss, sslen, hbuf, sizeof(hbuf),
                     NULL, 0,
                     NI_NUMERICHOST | NI_NUMERICSERV | NI_WITHSCOPEID);

   if(rc) {
     printf("rc = %s\n", gai_strerror(rc));
     return 3;
   }

   return 0; /* everything works fine, use NI_WITHSCOPEID! */
#else
   return 4; /* we don't seem to have the definition, don't use it */
#endif
}
]],
dnl program worked:
[ ac_cv_working_ni_withscopeid="yes" ],
dnl program failed:
[ ac_cv_working_ni_withscopeid="no" ],
dnl we cross-compile, check the headers using the preprocessor
[

 AC_EGREP_CPP(WORKS,
[
#include <stdio.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>

#ifdef NI_WITHSCOPEID
WORKS
#endif
],
  ac_cv_working_ni_withscopeid="yes",
  ac_cv_working_ni_withscopeid="no" )

 ]
) dnl end of AC_RUN_IFELSE

]) dnl end of AC_CACHE_CHECK

if test "$ac_cv_working_ni_withscopeid" = "yes"; then
  AC_DEFINE(HAVE_NI_WITHSCOPEID, 1,
            [Define if NI_WITHSCOPEID exists and works])
fi

]) dnl end of AC_DEFUN


AC_DEFUN([CURL_CHECK_LOCALTIME_R],
[
  dnl check for localtime_r
  AC_CHECK_FUNCS(localtime_r,[
    AC_MSG_CHECKING(whether localtime_r is declared)
    AC_EGREP_CPP(localtime_r,[
#include <time.h>],[
      AC_MSG_RESULT(yes)],[
      AC_MSG_RESULT(no)
      AC_MSG_CHECKING(whether localtime_r with -D_REENTRANT is declared)
      AC_EGREP_CPP(localtime_r,[
#define _REENTRANT
#include <time.h>],[
	AC_DEFINE(NEED_REENTRANT)
	AC_MSG_RESULT(yes)],
	AC_MSG_RESULT(no))])])
])

dnl
dnl This function checks for strerror_r(). If it isn't found at first, it
dnl retries with _THREAD_SAFE defined, as that is what AIX seems to require
dnl in order to find this function.
dnl
dnl If the function is found, it will then proceed to check how the function
dnl actually works: glibc-style or POSIX-style.
dnl
dnl glibc:
dnl      char *strerror_r(int errnum, char *buf, size_t n);
dnl  
dnl  What this one does is to return the error string (no surprises there),
dnl  but it doesn't usually copy anything into buf!  The 'buf' and 'n'
dnl  parameters are only meant as an optional working area, in case strerror_r
dnl  needs it.  A quick test on a few systems shows that it's generally not
dnl  touched at all.
dnl
dnl POSIX:
dnl      int strerror_r(int errnum, char *buf, size_t n);
dnl
AC_DEFUN([CURL_CHECK_STRERROR_R],
[
  AC_CHECK_FUNCS(strerror_r)

  if test "x$ac_cv_func_strerror_r" = "xyes"; then

    AC_MSG_CHECKING(whether strerror_r is declared)
    AC_EGREP_CPP(strerror_r,[
#include <string.h>],[
      AC_MSG_RESULT(yes)],[
      AC_MSG_RESULT(no)
      AC_MSG_CHECKING(whether strerror_r with -D_REENTRANT is declared)
      AC_EGREP_CPP(strerror_r,[
#define _REENTRANT
#include <string.h>],[
	CPPFLAGS="-D_REENTRANT $CPPFLAGS"
	AC_MSG_RESULT(yes)],
	AC_MSG_RESULT(no)
        AC_DEFINE(HAVE_NO_STRERROR_R_DECL, 1, [we have no strerror_r() proto])
       ) dnl with _THREAD_SAFE
    ]) dnl plain cpp for it

    dnl determine if this strerror_r() is glibc or POSIX
    AC_MSG_CHECKING([for a glibc strerror_r API])
    AC_TRY_RUN([
#include <string.h>
#include <errno.h>
int
main () {
  char buffer[1024]; /* big enough to play with */
  char *string =
    strerror_r(EACCES, buffer, sizeof(buffer));
    /* this should've returned a string */
    if(!string || !string[0])
      return 99;
    return 0;
}
],
    GLIBC_STRERROR_R="1"
    AC_DEFINE(HAVE_GLIBC_STRERROR_R, 1, [we have a glibc-style strerror_r()])
    AC_MSG_RESULT([yes]),
    AC_MSG_RESULT([no]),

    dnl Use an inferior method of strerror_r detection while cross-compiling
    AC_EGREP_CPP(yes, [
#include <features.h>
#ifdef __GLIBC__
yes
#endif
], 
      dnl looks like glibc, so assume a glibc-style strerror_r()
      GLIBC_STRERROR_R="1"
      AC_DEFINE(HAVE_GLIBC_STRERROR_R, 1, [we have a glibc-style strerror_r()])
      AC_MSG_RESULT([yes]),
      AC_MSG_NOTICE([cannot determine strerror_r() style: edit lib/config.h manually!])
    ) dnl while cross-compiling
    )

    if test -z "$GLIBC_STRERROR_R"; then

      AC_MSG_CHECKING([for a POSIX strerror_r API])
      AC_TRY_RUN([
#include <string.h>
#include <errno.h>
int
main () {
  char buffer[1024]; /* big enough to play with */
  int error =
    strerror_r(EACCES, buffer, sizeof(buffer));
    /* This should've returned zero, and written an error string in the
       buffer.*/
    if(!buffer[0] || error)
      return 99;
    return 0;
}
],
      AC_DEFINE(HAVE_POSIX_STRERROR_R, 1, [we have a POSIX-style strerror_r()])
      AC_MSG_RESULT([yes]),
      AC_MSG_RESULT([no]) ,
      dnl cross-compiling!
      AC_MSG_NOTICE([cannot determine strerror_r() style: edit lib/config.h manually!])
    )