[WS] Fix peer stuck in CLOSING state

[Faless]

This was due by the buffer being cleared on close (including in closing state) preventing further reads.

This commit changes the close logic to only clear the buffer when the peer connection has been fully closed (acknowledged by the other end, or closed due to a "broken" connection).

Fixes #100948

[mhilbrunner]

Wouldn't the same bug lurk here?

godot/modules/websocket/emws_peer.cpp

Lines 180 to 198 in 7b1ed52

	void EMWSPeer::close(int p_code, String p_reason) {
	if (p_code < 0) {
	if (peer_sock != -1) {
	godot_js_websocket_destroy(peer_sock);
	peer_sock = -1;
	}
	ready_state = STATE_CLOSED;
	}
	if (ready_state == STATE_CONNECTING || ready_state == STATE_OPEN) {
	ready_state = STATE_CLOSING;
	if (peer_sock != -1) {
	godot_js_websocket_close(peer_sock, p_code, p_reason.utf8().get_data());
	} else {
	ready_state = STATE_CLOSED;
	}
	}
	in_buffer.clear();
	packet_buffer.clear();
	}

(EMWSPeer::close() clearing in_buffer and packet_buffer when STATE_CLOSING instead of only in STATE_CLOSED)

[Faless]

Wouldn't the same bug lurk here?

Not really, at least for now, because we can't control reads on the Web, since the Web API is callback-based (so reads will happen even if the buffer if zero, and we'd be dropping data, but close events will always be processed):

godot/modules/websocket/emws_peer.cpp

Lines 54 to 59 in 7b1ed52

	void EMWSPeer::_esws_on_close(void *p_obj, int p_code, const char *p_reason, int p_was_clean) {
	EMWSPeer *peer = static_cast<EMWSPeer *>(p_obj);
	peer->close_code = p_code;
	peer->close_reason.parse_utf8(p_reason);
	peer->ready_state = STATE_CLOSED;
	}

godot/modules/websocket/library_godot_websocket.js

Lines 113 to 120 in 7b1ed52

	create: function (socket, p_on_open, p_on_message, p_on_error, p_on_close) {
	const id = IDHandler.add(socket);
	socket.onopen = GodotWebSocket._onopen.bind(null, id, p_on_open);
	socket.onmessage = GodotWebSocket._onmessage.bind(null, id, p_on_message);
	socket.onerror = GodotWebSocket._onerror.bind(null, id, p_on_error);
	socket.onclose = GodotWebSocket._onclose.bind(null, id, p_on_close);
	return id;
	},

[Repiteo]

Thanks!