dnl This is copyright Rüdiger Kuhlmann <info@ruediger-kuhlmann.de>

AC_DEFUN([AC_FUNC_SNPRINTF],
[AC_CHECK_FUNCS(snprintf vsnprintf)
AC_MSG_CHECKING(for working snprintf)
AC_CACHE_VAL(ac_cv_have_working_snprintf,
[AC_TRY_RUN(
[#include <stdio.h>

int main(void)
{
    char bufs[5] = { 'x', 'x', 'x', '\0', '\0' };
    char bufd[5] = { 'x', 'x', 'x', '\0', '\0' };
    int i;
    i = snprintf (bufs, 2, "%s", "111");
    if (strcmp (bufs, "1")) exit (1);
    if (i != 3) exit (1);
    i = snprintf (bufd, 2, "%d", 111);
    if (strcmp (bufd, "1")) exit (1);
    if (i != 3) exit (1);
    exit(0);
}], ac_cv_have_working_snprintf=yes, ac_cv_have_working_snprintf=no, ac_cv_have_working_snprintf=cross)])
AC_MSG_RESULT([$ac_cv_have_working_snprintf])
AC_MSG_CHECKING(for working vsnprintf)
AC_CACHE_VAL(ac_cv_have_working_vsnprintf,
[AC_TRY_RUN(
[#include <stdio.h>
#include <stdarg.h>

int my_vsnprintf (char *buf, const char *tmpl, ...)
{
    int i;
    va_list args;
    va_start (args, tmpl);
    i = vsnprintf (buf, 2, tmpl, args);
    va_end (args);
    return i;
}

int main(void)
{
    char bufs[5] = { 'x', 'x', 'x', '\0', '\0' };
    char bufd[5] = { 'x', 'x', 'x', '\0', '\0' };
    int i;
    i = my_vsnprintf (bufs, "%s", "111");
    if (strcmp (bufs, "1")) exit (1);
    if (i != 3) exit (1);
    i = my_vsnprintf (bufd, "%d", 111);
    if (strcmp (bufd, "1")) exit (1);
    if (i != 3) exit (1);
    exit(0);
}], ac_cv_have_working_vsnprintf=yes, ac_cv_have_working_vsnprintf=no, ac_cv_have_working_vsnprintf=cross)])
AC_MSG_RESULT([$ac_cv_have_working_vsnprintf])
if test x$ac_cv_have_working_snprintf$ac_cv_have_working_vsnprintf != "xyesyes"; then
  AC_LIBOBJ(snprintf)
  AC_MSG_WARN([Replacing missing/broken (v)snprintf() with version from http://www.ijs.si/software/snprintf/.])
  AC_DEFINE(PREFER_PORTABLE_SNPRINTF, 1, "enable replacement (v)snprintf if system (v)snprintf is broken")
fi])

dnl This macro figures out what libraries are required on this platform to link
dnl sockets programs. It's usually -lsocket and/or -lnsl or neither. We test for
dnl all three combinations.
dnl Copyright Warren Young <warren@etr-usa.com>

AC_DEFUN([ETR_SOCKET_NSL],
[
AC_CACHE_CHECK(for libraries containing socket functions,
ac_cv_socket_libs, [
        oCFLAGS=$CFLAGS

        AC_TRY_LINK([
                        #include <sys/types.h>
                        #include <sys/socket.h>
                        #include <netinet/in.h>
                        #include <arpa/inet.h>
                ],
                [
                        struct in_addr add;
                        int sd = socket(AF_INET, SOCK_STREAM, 0);
                        inet_ntoa(add);
                ],
                ac_cv_socket_libs=-lc, ac_cv_socket_libs=no)

        if test x"$ac_cv_socket_libs" = "xno"
        then
                CFLAGS="$oCFLAGS -lsocket"
                AC_TRY_LINK([
                                #include <sys/types.h>
                                #include <sys/socket.h>
                                #include <netinet/in.h>
                                #include <arpa/inet.h>
                        ],
                        [
                                struct in_addr add;
                                int sd = socket(AF_INET, SOCK_STREAM, 0);
                                inet_ntoa(add);
                        ],
                        ac_cv_socket_libs=-lsocket, ac_cv_socket_libs=no)
        fi

        if test x"$ac_cv_socket_libs" = "xno"
        then
                CFLAGS="$oCFLAGS -lsocket -lnsl"
                AC_TRY_LINK([
                                #include <sys/types.h>
                                #include <sys/socket.h>
                                #include <netinet/in.h>
                                #include <arpa/inet.h>
                        ],
                        [
                                struct in_addr add;
                                int sd = socket(AF_INET, SOCK_STREAM, 0);
                                inet_ntoa(add);
                        ],
                        ac_cv_socket_libs="-lsocket -lnsl", ac_cv_socket_libs=no)
        fi

        CFLAGS=$oCFLAGS
])

        if test x"$ac_cv_socket_libs" = "xno"
        then
                AC_MSG_ERROR([Cannot find socket libraries])
        elif test x"$ac_cv_socket_libs" = "x-lc"
        then
                ETR_SOCKET_LIBS=""
        else
                ETR_SOCKET_LIBS="$ac_cv_socket_libs"
        fi

        AC_SUBST(ETR_SOCKET_LIBS)
]) dnl ETR_SOCKET_NSL