initial commit, 4.5 stable

modules/websocket/packet_buffer.h

@@ -0,0 +1,129 @@
+/**************************************************************************/
+/*  packet_buffer.h                                                       */
+/**************************************************************************/
+/*                         This file is part of:                          */
+/*                             GODOT ENGINE                               */
+/*                        https://godotengine.org                         */
+/**************************************************************************/
+/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
+/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur.                  */
+/*                                                                        */
+/* Permission is hereby granted, free of charge, to any person obtaining  */
+/* a copy of this software and associated documentation files (the        */
+/* "Software"), to deal in the Software without restriction, including    */
+/* without limitation the rights to use, copy, modify, merge, publish,    */
+/* distribute, sublicense, and/or sell copies of the Software, and to     */
+/* permit persons to whom the Software is furnished to do so, subject to  */
+/* the following conditions:                                              */
+/*                                                                        */
+/* The above copyright notice and this permission notice shall be         */
+/* included in all copies or substantial portions of the Software.        */
+/*                                                                        */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,        */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF     */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY   */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,   */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE      */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                 */
+/**************************************************************************/
+
+#pragma once
+
+#include "core/templates/ring_buffer.h"
+
+template <typename T>
+class PacketBuffer {
+private:
+	typedef struct {
+		uint32_t size;
+		T info;
+	} _Packet;
+
+	Vector<_Packet> _packets;
+	int _queued = 0;
+	int _write_pos = 0;
+	int _read_pos = 0;
+	RingBuffer<uint8_t> _payload;
+
+public:
+	Error write_packet(const uint8_t *p_payload, uint32_t p_size, const T *p_info) {
+		ERR_FAIL_COND_V_MSG(p_payload && (uint32_t)_payload.space_left() < p_size, ERR_OUT_OF_MEMORY, "Buffer payload full! Dropping data.");
+		ERR_FAIL_COND_V_MSG(p_info && _queued >= _packets.size(), ERR_OUT_OF_MEMORY, "Too many packets in queue! Dropping data.");
+
+		// If p_info is nullptr, only the payload is written
+		if (p_info) {
+			ERR_FAIL_COND_V(_write_pos > _packets.size(), ERR_OUT_OF_MEMORY);
+			_Packet p;
+			p.size = p_size;
+			p.info = *p_info;
+			_packets.write[_write_pos] = p;
+			_queued += 1;
+			_write_pos++;
+			if (_write_pos >= _packets.size()) {
+				_write_pos = 0;
+			}
+		}
+
+		// If p_payload is nullptr, only the packet information is written.
+		if (p_payload) {
+			_payload.write((const uint8_t *)p_payload, p_size);
+		}
+
+		return OK;
+	}
+
+	Error read_packet(uint8_t *r_payload, int p_bytes, T *r_info, int &r_read) {
+		ERR_FAIL_COND_V(_queued < 1, ERR_UNAVAILABLE);
+		_Packet p = _packets[_read_pos];
+		_read_pos += 1;
+		if (_read_pos >= _packets.size()) {
+			_read_pos = 0;
+		}
+		_queued -= 1;
+
+		ERR_FAIL_COND_V(_payload.data_left() < (int)p.size, ERR_BUG);
+		ERR_FAIL_COND_V(p_bytes < (int)p.size, ERR_OUT_OF_MEMORY);
+
+		r_read = p.size;
+		memcpy(r_info, &p.info, sizeof(T));
+		_payload.read(r_payload, p.size);
+		return OK;
+	}
+
+	void resize(int p_buf_shift, int p_max_packets) {
+		_payload.resize(p_buf_shift);
+		_packets.resize(p_max_packets);
+		_read_pos = 0;
+		_write_pos = 0;
+		_queued = 0;
+	}
+
+	int packets_left() const {
+		return _queued;
+	}
+
+	int payload_space_left() const {
+		return _payload.space_left();
+	}
+
+	int packets_space_left() const {
+		return _packets.size() - _queued;
+	}
+
+	void clear() {
+		_payload.resize(0);
+		_packets.resize(0);
+		_read_pos = 0;
+		_write_pos = 0;
+		_queued = 0;
+	}
+
+	PacketBuffer() {
+		clear();
+	}
+
+	~PacketBuffer() {
+		clear();
+	}
+};