# inet_pton.m4 serial 19

dnl Copyright (C) 2006, 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.

AC_DEFUN([gl_FUNC_INET_PTON],

[

  AC_REQUIRE([gl_ARPA_INET_H_DEFAULTS])

  dnl Persuade Solaris <arpa/inet.h> to declare inet_pton.

  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])

  AC_REQUIRE([AC_C_RESTRICT])

  dnl Most platforms that provide inet_pton define it in libc.

  dnl Solaris 8..10 provide inet_pton in libnsl instead.

  dnl Solaris 2.6..7 provide inet_pton in libresolv instead.

  dnl Haiku provides it in -lnetwork.

  dnl Native Windows provides it in -lws2_32 instead, with a declaration in

  dnl <ws2tcpip.h>, and it uses stdcall calling convention, not cdecl

  dnl (hence we cannot use AC_CHECK_FUNCS, AC_SEARCH_LIBS to find it).

  HAVE_INET_PTON=1

  INET_PTON_LIB=

  gl_PREREQ_SYS_H_WINSOCK2

  if test $HAVE_WINSOCK2_H = 1; then

    dnl It needs to be overridden, because the stdcall calling convention

    dnl is not compliant with POSIX.  Set REPLACE_INET_PTON in order to avoid

    dnl a name conflict at the linker level, even though the header file

    dnl <ws2tcpip.h> declares inet_pton only if _WIN32_WINNT >= 0x0600.

    REPLACE_INET_PTON=1

    AC_CHECK_DECLS([inet_pton],,, [[#include <ws2tcpip.h>]])

    if test $ac_cv_have_decl_inet_pton = yes; then

      INET_PTON_LIB="-lws2_32"

    else

      HAVE_DECL_INET_PTON=0

    fi

  else

    gl_save_LIBS=$LIBS

    AC_SEARCH_LIBS([inet_pton], [nsl resolv network], [],

      [AC_CHECK_FUNCS([inet_pton])

       if test $ac_cv_func_inet_pton = no; then

         HAVE_INET_PTON=0

       fi

      ])

    LIBS=$gl_save_LIBS

    if test "$ac_cv_search_inet_pton" != "no" \

       && test "$ac_cv_search_inet_pton" != "none required"; then

      INET_PTON_LIB="$ac_cv_search_inet_pton"

    fi

    AC_CHECK_HEADERS_ONCE([netdb.h])

    AC_CHECK_DECLS([inet_pton],,,

      [[#include <arpa/inet.h>

        #if HAVE_NETDB_H

        # include <netdb.h>

        #endif

      ]])

    if test $ac_cv_have_decl_inet_pton = no; then

      HAVE_DECL_INET_PTON=0

    fi

  fi

  AC_SUBST([INET_PTON_LIB])

])

# Prerequisites of lib/inet_pton.c.

AC_DEFUN([gl_PREREQ_INET_PTON], [

  AC_REQUIRE([gl_SOCKET_FAMILIES])

])