+ AC_CHECK_HEADERS(zlib.h,,AC_MSG_ERROR([required C header missing!]))
+fi
+
+# detect which IO API to use:
+
+x_io_backend=none
+
+AC_ARG_WITH(select,
+ AS_HELP_STRING([--without-select],
+ [disable select IO support (autodetected by default)]),
+ [ if test "$withval" != "no"; then
+ if test "$withval" != "yes"; then
+ CFLAGS="-I$withval/include $CFLAGS"
+ CPPFLAGS="-I$withval/include $CPPFLAGS"
+ LDFLAGS="-L$withval/lib $LDFLAGS"
+ fi
+ AC_CHECK_FUNCS(select, x_io_select=yes,
+ AC_MSG_ERROR([Can't enable select IO support!])
+ )
+ fi
+ ],
+ [
+ AC_CHECK_FUNCS(select, x_io_select=yes)
+ ]
+)
+
+AC_ARG_WITH(poll,
+ AS_HELP_STRING([--without-poll],
+ [disable poll support (autodetected by default)]),
+ [ if test "$withval" != "no"; then
+ if test "$withval" != "yes"; then
+ CFLAGS="-I$withval/include $CFLAGS"
+ CPPFLAGS="-I$withval/include $CPPFLAGS"
+ LDFLAGS="-L$withval/lib $LDFLAGS"
+ fi
+ AC_CHECK_FUNCS(poll, [
+ AC_CHECK_HEADERS(poll.h,
+ x_io_backend=poll\(\),
+ AC_MSG_ERROR(
+ [Can't enable poll IO support!])
+ )
+ ], [
+ AC_MSG_ERROR([Can't enable poll IO support!])
+ ])
+ fi
+ ],
+ [
+ AC_CHECK_FUNCS(poll, [
+ AC_CHECK_HEADERS(poll.h, x_io_backend=poll\(\))
+ ])
+ ]
+)
+
+AC_ARG_WITH(devpoll,
+ AS_HELP_STRING([--without-devpoll],
+ [disable /dev/poll IO support (autodetected by default)]),
+ [ if test "$withval" != "no"; then
+ if test "$withval" != "yes"; then
+ CFLAGS="-I$withval/include $CFLAGS"
+ CPPFLAGS="-I$withval/include $CPPFLAGS"
+ LDFLAGS="-L$withval/lib $LDFLAGS"
+ fi
+
+ AC_CHECK_HEADERS(sys/devpoll.h,,AC_MSG_ERROR([required C header missing!]))
+ fi
+ ],
+ [
+ AC_CHECK_HEADERS(sys/devpoll.h, x_io_backend=/dev/poll)
+ ]
+)
+
+AC_ARG_WITH(epoll,
+ AS_HELP_STRING([--without-epoll],
+ [disable epoll IO support (autodetected by default)]),
+ [ if test "$withval" != "no"; then
+ if test "$withval" != "yes"; then
+ CFLAGS="-I$withval/include $CFLAGS"
+ CPPFLAGS="-I$withval/include $CPPFLAGS"
+ LDFLAGS="-L$withval/lib $LDFLAGS"
+ fi
+ AC_CHECK_FUNCS(epoll_create, x_io_epoll=yes,
+ AC_MSG_ERROR([Can't enable epoll IO support!])
+ )
+ fi
+ ],
+ [
+ AC_CHECK_FUNCS(epoll_create, x_io_epoll=yes)
+ ]
+)
+
+AC_ARG_WITH(kqueue,
+ AS_HELP_STRING([--without-kqueue],
+ [disable kqueue IO support (autodetected by default)]),
+ [ if test "$withval" != "no"; then
+ if test "$withval" != "yes"; then
+ CFLAGS="-I$withval/include $CFLAGS"
+ CPPFLAGS="-I$withval/include $CPPFLAGS"
+ LDFLAGS="-L$withval/lib $LDFLAGS"
+ fi
+ AC_CHECK_FUNCS(kqueue, x_io_backend=kqueue\(\),
+ AC_MSG_ERROR([Can't enable kqueue IO support!])
+ )
+ fi
+ ],
+ [
+ AC_CHECK_FUNCS(kqueue, x_io_backend=kqueue\(\))
+ ]
+)
+
+if test "$x_io_epoll" = "yes" -a "$x_io_select" = "yes"; then
+ # when epoll() and select() are available, we'll use both!
+ x_io_backend="epoll(), select()"
+else
+ if test "$x_io_epoll" = "yes"; then
+ # we prefere epoll() if it is available
+ x_io_backend="epoll()"
+ else
+ if test "$x_io_select" = "yes" -a "$x_io_backend" = "none"; then
+ # we'll use select, when available and no "better"
+ # interface has been detected ...
+ x_io_backend="select()"
+ fi
+ fi