| /* |
| * Copyright (c) 2016 The WebRTC project authors. All Rights Reserved. |
| * |
| * Use of this source code is governed by a BSD-style license |
| * that can be found in the LICENSE file in the root of the source |
| * tree. An additional intellectual property rights grant can be found |
| * in the file PATENTS. All contributing project authors may |
| * be found in the AUTHORS file in the root of the source tree. |
| */ |
| #ifndef WEBRTC_MODULES_RTP_RTCP_SOURCE_RTP_PACKET_H_ |
| #define WEBRTC_MODULES_RTP_RTCP_SOURCE_RTP_PACKET_H_ |
| |
| #include <vector> |
| |
| #include "webrtc/api/array_view.h" |
| #include "webrtc/modules/rtp_rtcp/include/rtp_rtcp_defines.h" |
| #include "webrtc/rtc_base/basictypes.h" |
| #include "webrtc/rtc_base/copyonwritebuffer.h" |
| |
| namespace webrtc { |
| class RtpHeaderExtensionMap; |
| class Random; |
| |
| class RtpPacket { |
| public: |
| using ExtensionType = RTPExtensionType; |
| using ExtensionManager = RtpHeaderExtensionMap; |
| static constexpr int kMaxExtensionHeaders = 14; |
| static constexpr int kMinExtensionId = 1; |
| static constexpr int kMaxExtensionId = 14; |
| |
| // |extensions| required for SetExtension/ReserveExtension functions during |
| // packet creating and used if available in Parse function. |
| // Adding and getting extensions will fail until |extensions| is |
| // provided via constructor or IdentifyExtensions function. |
| RtpPacket(); |
| explicit RtpPacket(const ExtensionManager* extensions); |
| RtpPacket(const RtpPacket&); |
| RtpPacket(const ExtensionManager* extensions, size_t capacity); |
| ~RtpPacket(); |
| |
| RtpPacket& operator=(const RtpPacket&) = default; |
| |
| // Parse and copy given buffer into Packet. |
| bool Parse(const uint8_t* buffer, size_t size); |
| bool Parse(rtc::ArrayView<const uint8_t> packet); |
| |
| // Parse and move given buffer into Packet. |
| bool Parse(rtc::CopyOnWriteBuffer packet); |
| |
| // Maps extensions id to their types. |
| void IdentifyExtensions(const ExtensionManager& extensions); |
| |
| // Header. |
| bool Marker() const; |
| uint8_t PayloadType() const; |
| uint16_t SequenceNumber() const; |
| uint32_t Timestamp() const; |
| uint32_t Ssrc() const; |
| std::vector<uint32_t> Csrcs() const; |
| |
| size_t headers_size() const; |
| |
| // Payload. |
| size_t payload_size() const; |
| size_t padding_size() const; |
| rtc::ArrayView<const uint8_t> payload() const; |
| |
| // Buffer. |
| rtc::CopyOnWriteBuffer Buffer() const; |
| size_t capacity() const; |
| size_t size() const; |
| const uint8_t* data() const; |
| size_t FreeCapacity() const; |
| size_t MaxPayloadSize() const; |
| |
| // Reset fields and buffer. |
| void Clear(); |
| |
| // Header setters. |
| void CopyHeaderFrom(const RtpPacket& packet); |
| void SetMarker(bool marker_bit); |
| void SetPayloadType(uint8_t payload_type); |
| void SetSequenceNumber(uint16_t seq_no); |
| void SetTimestamp(uint32_t timestamp); |
| void SetSsrc(uint32_t ssrc); |
| |
| // Writes csrc list. Assumes: |
| // a) There is enough room left in buffer. |
| // b) Extension headers, payload or padding data has not already been added. |
| void SetCsrcs(const std::vector<uint32_t>& csrcs); |
| |
| // Header extensions. |
| template <typename Extension> |
| bool HasExtension() const; |
| |
| template <typename Extension, typename... Values> |
| bool GetExtension(Values...) const; |
| |
| template <typename Extension, typename... Values> |
| bool SetExtension(Values...); |
| |
| template <typename Extension> |
| bool ReserveExtension(); |
| |
| // Following 4 helpers identify rtp header extension by |id| negotiated with |
| // remote peer and written in an rtp packet. |
| bool HasRawExtension(int id) const; |
| |
| // Returns place where extension with |id| is stored. |
| // Returns empty arrayview if extension is not present. |
| rtc::ArrayView<const uint8_t> GetRawExtension(int id) const; |
| |
| // Allocates and store header extension. Returns true on success. |
| bool SetRawExtension(int id, rtc::ArrayView<const uint8_t> data); |
| |
| // Allocates and returns place to store rtp header extension. |
| // Returns empty arrayview on failure. |
| rtc::ArrayView<uint8_t> AllocateRawExtension(int id, size_t length); |
| |
| // Reserve size_bytes for payload. Returns nullptr on failure. |
| uint8_t* SetPayloadSize(size_t size_bytes); |
| // Same as SetPayloadSize but doesn't guarantee to keep current payload. |
| uint8_t* AllocatePayload(size_t size_bytes); |
| bool SetPadding(uint8_t size_bytes, Random* random); |
| |
| private: |
| struct ExtensionInfo { |
| ExtensionType type; |
| uint16_t offset; |
| uint8_t length; |
| }; |
| |
| // Helper function for Parse. Fill header fields using data in given buffer, |
| // but does not touch packet own buffer, leaving packet in invalid state. |
| bool ParseBuffer(const uint8_t* buffer, size_t size); |
| |
| // Find an extension |type|. |
| // Returns view of the raw extension or empty view on failure. |
| rtc::ArrayView<const uint8_t> FindExtension(ExtensionType type) const; |
| |
| // Find or allocate an extension |type|. Returns view of size |length| |
| // to write raw extension to or an empty view on failure. |
| rtc::ArrayView<uint8_t> AllocateExtension(ExtensionType type, size_t length); |
| |
| uint8_t* WriteAt(size_t offset); |
| void WriteAt(size_t offset, uint8_t byte); |
| |
| // Header. |
| bool marker_; |
| uint8_t payload_type_; |
| uint8_t padding_size_; |
| uint16_t sequence_number_; |
| uint32_t timestamp_; |
| uint32_t ssrc_; |
| size_t payload_offset_; // Match header size with csrcs and extensions. |
| size_t payload_size_; |
| |
| ExtensionInfo extension_entries_[kMaxExtensionHeaders]; |
| uint16_t extensions_size_ = 0; // Unaligned. |
| rtc::CopyOnWriteBuffer buffer_; |
| }; |
| |
| template <typename Extension> |
| bool RtpPacket::HasExtension() const { |
| return !FindExtension(Extension::kId).empty(); |
| } |
| |
| template <typename Extension, typename... Values> |
| bool RtpPacket::GetExtension(Values... values) const { |
| auto raw = FindExtension(Extension::kId); |
| if (raw.empty()) |
| return false; |
| return Extension::Parse(raw, values...); |
| } |
| |
| template <typename Extension, typename... Values> |
| bool RtpPacket::SetExtension(Values... values) { |
| const size_t value_size = Extension::ValueSize(values...); |
| if (value_size == 0 || value_size > 16) |
| return false; |
| auto buffer = AllocateExtension(Extension::kId, value_size); |
| if (buffer.empty()) |
| return false; |
| return Extension::Write(buffer.data(), values...); |
| } |
| |
| template <typename Extension> |
| bool RtpPacket::ReserveExtension() { |
| auto buffer = AllocateExtension(Extension::kId, Extension::kValueSizeBytes); |
| if (buffer.empty()) |
| return false; |
| memset(buffer.data(), 0, Extension::kValueSizeBytes); |
| return true; |
| } |
| |
| } // namespace webrtc |
| |
| #endif // WEBRTC_MODULES_RTP_RTCP_SOURCE_RTP_PACKET_H_ |