server: add websockets support via libwebsockets

New API: spice_server_set_ws_ports

This adds an optional dependency on libwebsockets. You need to get my
patched 0.0.3 version here:
 git://people.freedesktop.org/~alon/libwebsockets

There is no qemu patches yet, to test change in reds.c the default value
of spice_ws_port to 5959 (for the default of spice-html5).

For testing there is an online client at
 http://spice-space.org/spice-html5/spice.html

Known issues:
 1. The tester (server/tests/test_display_no_ssl) gets into dropping all
  data after a few seconds, I think it's an issue with the implemented
  watches, but haven't figured it out.

 2. libwebsocket's read interface is inverted to what our code expects,
 i.e. there is no libwebsocket_read, so there is an additional copy
 involved (see RedsWebSocket). This can be fixed.

 3. Listening on a separate port. Since the headers are different, we
 could listen on the same port (first three bytes RED/GET). I don't know
 if we want to?

Todos:
 1. SSL not implemented yet. Needs some thought as to how.

 2. Serve spice-html5 when accessed as a http server. Nice to have.

1 files changed, 7 insertions, 0 deletions

diff --git a/server/spice.h b/server/spice.h
index c1478e0f..7ca5033c 100644
--- a/server/spice.h
+++ b/server/spice.h
@@ -434,6 +434,13 @@ void spice_server_destroy(SpiceServer *s);
 int spice_server_set_compat_version(SpiceServer *s,
                                     spice_compat_version_t version);
 int spice_server_set_port(SpiceServer *s, int port);
+
+/* @ws_port: -1 for don't set, otherwise in [1,65535] port to listen
+ *           for unencrypted websocket connections.
+ * @wss_port: -1 for don't set, otherwise in [1,65535] port to listen
+ *           for encrypted websocket connections.
+ */
+int spice_server_set_ws_ports(SpiceServer *s, int ws_port, int wss_port);
 void spice_server_set_addr(SpiceServer *s, const char *addr, int flags);
 int spice_server_set_listen_socket_fd(SpiceServer *s, int listen_fd);
 int spice_server_set_exit_on_disconnect(SpiceServer *s, int flag);