AC_DEFUN(DC_DO_WIN32, [
  AC_CHECK_HEADERS(windows.h windowsx.h winsock2.h)
  AC_CHECK_LIB(wsock32, main, [
    AC_DEFINE(HAVE_LIBWSOCK32, [], [Have libwsock32])
      LIBS="${LIBS} -lwsock32"
  ])
])

AC_DEFUN(DC_DO_NETSET, [
  AC_SEARCH_LIBS(socket, socket nsl ws2_32 wsock32, AC_DEFINE(HAVE_SOCKET, [], [Have socket()]))
  AC_SEARCH_LIBS(gethostbyname, nsl ws2_32 wsock32, AC_DEFINE(HAVE_GETHOSTBYNAME, [], [Have gethostbyname()]))
  AC_SEARCH_LIBS(inet_aton, xnet ws2_32 wsock32, AC_DEFINE(HAVE_INET_ATON, [], [Have inet_aton()]), AC_SEARCH_LIBS(inet_addr, nsl ws2_32 wsock32, AC_DEFINE(HAVE_INET_ADDR, [], [Have inet_addr()])))
])

AC_DEFUN(DC_DO_TYPE, [
	if test -z "$ac_cv_sizeof_long"; then
		AC_C_INLINE
		AC_CHECK_SIZEOF(long long, 8)
		AC_CHECK_SIZEOF(long, 4)
		AC_CHECK_SIZEOF(int, 4)
		AC_CHECK_SIZEOF(short, 2)
	fi
	FOUND=0
	for dc_cv_loop in \$ac_cv_sizeof_long_long \$ac_cv_sizeof_int \$ac_cv_sizeof_long \$ac_cv_sizeof_short; do
		dc_cv_size=`eval echo $dc_cv_loop`
		dc_cv_name=`echo $dc_cv_loop | sed s/\\\$ac_cv_sizeof_//`
		if test "$dc_cv_size" = "$3"; then
			if test "$dc_cv_name" = "int"; then 
				AC_CHECK_TYPE($1, $2 int)
			fi
			if test "$dc_cv_name" = "long"; then
				AC_CHECK_TYPE($1, $2 long)
			fi
			if test "$dc_cv_name" = "long_long"; then
				AC_CHECK_TYPE($1, $2 long long)
			fi
			if test "$dc_cv_name" = "short"; then
				AC_CHECK_TYPE($1, $2 short)
			fi
			FOUND=1
			break
		fi
	done
])

dnl Usage:
dnl    DC_SETLDRUNPATH(path)
AC_DEFUN(DC_SETLDRUNPATH, [
  AC_SUBST(LDRUNPATH)
  OLD_LDFLAGS="$LDFLAGS"

  for testldflags in "-Wl,-rpath -Wl,$1" "-Wl,-R -Wl,$1"; do
    LDFLAGS="$OLD_LDFLAGS $testldflags"
    AC_TRY_LINK([#include <stdio.h>],
                [ return(0); ], [ LDRUNPATH="$LDRUNPATH $testldflags"; break ]);
  done

  LDFLAGS="$OLD_LDFLAGS"
])

dnl Usage:
dnl    DC_TEST_SHOBJFLAGS(shobjflags, shobjldflags, action-if-not-found)
dnl
AC_DEFUN(DC_TEST_SHOBJFLAGS, [
  AC_SUBST(SHOBJFLAGS)
  AC_SUBST(SHOBJLDFLAGS)

  OLD_LDFLAGS="$LDFLAGS"
  SHOBJFLAGS=""

  LDFLAGS="$OLD_LDFLAGS $1 $2"

  AC_TRY_LINK([#include <stdio.h>
int unrestst(void);], [ printf("okay\n"); unrestst(); return(0); ], [ SHOBJFLAGS="$1"; SHOBJLDFLAGS="$2" ], [
  LDFLAGS="$OLD_LDFLAGS"
  $3
])

  LDFLAGS="$OLD_LDFLAGS"
])

AC_DEFUN(DC_GET_SHOBJFLAGS, [
  AC_SUBST(SHOBJFLAGS)
  AC_SUBST(SHOBJLDFLAGS)

  AC_MSG_CHECKING(how to create shared objects)

  if test -z "$SHOBJFLAGS" -a -z "$SHOBJLDFLAGS"; then
    DC_TEST_SHOBJFLAGS([-fPIC -DPIC], [-shared -rdynamic], [
      DC_TEST_SHOBJFLAGS([-fPIC -DPIC], [-shared], [
        DC_TEST_SHOBJFLAGS([-fPIC -DPIC], [-shared -rdynamic -mimpure-text], [
          DC_TEST_SHOBJFLAGS([-fPIC -DPIC], [-shared -mimpure-text], [
            DC_TEST_SHOBJFLAGS([-fPIC -DPIC], [-shared -rdynamic -Wl,-G,-z,textoff], [
              DC_TEST_SHOBJFLAGS([-fPIC -DPIC], [-shared -Wl,-G,-z,textoff], [
                DC_TEST_SHOBJFLAGS([-fPIC -DPIC], [-shared -dynamiclib -flat_namespace -undefined suppress -bind_at_load], [
                  DC_TEST_SHOBJFLAGS([-fPIC -DPIC], [-dynamiclib -flat_namespace -undefined suppress -bind_at_load], [
                    DC_TEST_SHOBJFLAGS([-fPIC -DPIC], [-Wl,-dynamiclib -Wl,-flat_namespace -Wl,-undefined,suppress -Wl,-bind_at_load], [
                      DC_TEST_SHOBJFLAGS([-fPIC -DPIC], [-dynamiclib -flat_namespace -undefined suppress], [
                        DC_TEST_SHOBJFLAGS([-fPIC -DPIC], [-dynamiclib], [
                          AC_MSG_RESULT(cant)
                          AC_MSG_ERROR([We are unable to make shared objects.])
                        ])
                      ])
                    ])
                  ])
                ])
              ])
            ])
          ])
        ])
      ])
    ])
  fi

  AC_MSG_RESULT($SHOBJLDFLAGS $SHOBJFLAGS)

  DC_SYNC_SHLIBOBJS
])

AC_DEFUN(DC_SYNC_SHLIBOBJS, [
  AC_SUBST(SHLIBOBJS)
  SHLIBOBJS=""
  for obj in $LIB@&t@OBJS; do
    SHLIBOBJS="$SHLIBOBJS `echo $obj | sed 's/\.o$/_shr.o/g'`"
  done
])

AC_DEFUN(DC_CHK_OS_INFO, [
	AC_CANONICAL_HOST
	AC_SUBST(SHOBJEXT)
	AC_SUBST(AREXT)
        AC_SUBST(SHOBJFLAGS)
        AC_SUBST(SHOBJLDFLAGS)

        AC_MSG_CHECKING(host operating system)
        AC_MSG_RESULT($host_os)

	SHOBJEXT="so"
	AREXT="a"

        case $host_os in
                darwin*)
			SHOBJEXT="dylib"
                        ;;
		hpux*)
			SHOBJEXT="sl"
			;;
		mingw32msvc*)
			SHOBJEXT="dll"
			SHOBJFLAGS="-mno-cygwin -mms-bitfields -DPIC"
			SHOBJLDFLAGS='-shared -Wl,--dll -Wl,--enable-auto-image-base -Wl,--output-def,$[@].def,--out-implib,$[@].a'
			;;
	esac
])