# socketlib.m4 serial 2

dnl Copyright (C) 2008-2020 Free Software Foundation, Inc.

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.

dnl gl_SOCKETLIB

dnl Determines the library to use for socket functions.

dnl Sets and AC_SUBSTs LIBSOCKET.

AC_DEFUN([gl_SOCKETLIB],

[

  gl_PREREQ_SYS_H_WINSOCK2 dnl for HAVE_WINSOCK2_H

  LIBSOCKET=

  if test $HAVE_WINSOCK2_H = 1; then

    dnl Native Windows API (not Cygwin).

    AC_CACHE_CHECK([if we need to call WSAStartup in winsock2.h and -lws2_32],

                   [gl_cv_func_wsastartup], [

      gl_save_LIBS="$LIBS"

      LIBS="$LIBS -lws2_32"

      AC_LINK_IFELSE([AC_LANG_PROGRAM([[

#ifdef HAVE_WINSOCK2_H

# include <winsock2.h>

#endif]], [[

          WORD wVersionRequested = MAKEWORD(1, 1);

          WSADATA wsaData;

          int err = WSAStartup(wVersionRequested, &wsaData);

          WSACleanup ();]])],

        gl_cv_func_wsastartup=yes, gl_cv_func_wsastartup=no)

      LIBS="$gl_save_LIBS"

    ])

    if test "$gl_cv_func_wsastartup" = "yes"; then

      AC_DEFINE([WINDOWS_SOCKETS], [1], [Define if WSAStartup is needed.])

      LIBSOCKET='-lws2_32'

    fi

  else

    dnl Unix API.

    dnl Solaris has most socket functions in libsocket.

    dnl Haiku has most socket functions in libnetwork.

    dnl BeOS has most socket functions in libnet.

    dnl On HP-UX, do NOT link with libxnet, because in 64-bit mode this would

    dnl break code (e.g. in libraries) that invokes accept(), getpeername(),

    dnl getsockname(), getsockopt(), or recvfrom() with a 32-bit addrlen. See

    dnl "man xopen_networking" for details.

    AC_CACHE_CHECK([for library containing setsockopt], [gl_cv_lib_socket], [

      gl_cv_lib_socket=

      AC_LINK_IFELSE([AC_LANG_PROGRAM([[extern

#ifdef __cplusplus

"C"

#endif

char setsockopt();]], [[setsockopt();]])],

        [],

        [gl_save_LIBS="$LIBS"

         LIBS="$gl_save_LIBS -lsocket"

         AC_LINK_IFELSE([AC_LANG_PROGRAM([[extern

#ifdef __cplusplus

"C"

#endif

char setsockopt();]], [[setsockopt();]])],

           [gl_cv_lib_socket="-lsocket"])

         if test -z "$gl_cv_lib_socket"; then

           LIBS="$gl_save_LIBS -lnetwork"

           AC_LINK_IFELSE([AC_LANG_PROGRAM([[extern

#ifdef __cplusplus

"C"

#endif

char setsockopt();]], [[setsockopt();]])],

             [gl_cv_lib_socket="-lnetwork"])

           if test -z "$gl_cv_lib_socket"; then

             LIBS="$gl_save_LIBS -lnet"

             AC_LINK_IFELSE([AC_LANG_PROGRAM([[extern

#ifdef __cplusplus

"C"

#endif

char setsockopt();]], [[setsockopt();]])],

               [gl_cv_lib_socket="-lnet"])

           fi

         fi

         LIBS="$gl_save_LIBS"

        ])

      if test -z "$gl_cv_lib_socket"; then

        gl_cv_lib_socket="none needed"

      fi

    ])

    if test "$gl_cv_lib_socket" != "none needed"; then

      LIBSOCKET="$gl_cv_lib_socket"

    fi

  fi

  AC_SUBST([LIBSOCKET])

])