diff options
Diffstat (limited to 'third_party/libwebrtc/modules/rtp_rtcp/source/rtp_util.cc')
-rw-r--r-- | third_party/libwebrtc/modules/rtp_rtcp/source/rtp_util.cc | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/third_party/libwebrtc/modules/rtp_rtcp/source/rtp_util.cc b/third_party/libwebrtc/modules/rtp_rtcp/source/rtp_util.cc new file mode 100644 index 0000000000..cf1e54254a --- /dev/null +++ b/third_party/libwebrtc/modules/rtp_rtcp/source/rtp_util.cc @@ -0,0 +1,63 @@ +/* + * Copyright (c) 2021 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. + */ + +#include "modules/rtp_rtcp/source/rtp_util.h" + +#include <cstddef> +#include <cstdint> + +#include "api/array_view.h" +#include "modules/rtp_rtcp/source/byte_io.h" +#include "rtc_base/checks.h" + +namespace webrtc { +namespace { + +constexpr uint8_t kRtpVersion = 2; +constexpr size_t kMinRtpPacketLen = 12; +constexpr size_t kMinRtcpPacketLen = 4; + +bool HasCorrectRtpVersion(rtc::ArrayView<const uint8_t> packet) { + return packet[0] >> 6 == kRtpVersion; +} + +// For additional details, see http://tools.ietf.org/html/rfc5761#section-4 +bool PayloadTypeIsReservedForRtcp(uint8_t payload_type) { + return 64 <= payload_type && payload_type < 96; +} + +} // namespace + +bool IsRtpPacket(rtc::ArrayView<const uint8_t> packet) { + return packet.size() >= kMinRtpPacketLen && HasCorrectRtpVersion(packet) && + !PayloadTypeIsReservedForRtcp(packet[1] & 0x7F); +} + +bool IsRtcpPacket(rtc::ArrayView<const uint8_t> packet) { + return packet.size() >= kMinRtcpPacketLen && HasCorrectRtpVersion(packet) && + PayloadTypeIsReservedForRtcp(packet[1] & 0x7F); +} + +int ParseRtpPayloadType(rtc::ArrayView<const uint8_t> rtp_packet) { + RTC_DCHECK(IsRtpPacket(rtp_packet)); + return rtp_packet[1] & 0x7F; +} + +uint16_t ParseRtpSequenceNumber(rtc::ArrayView<const uint8_t> rtp_packet) { + RTC_DCHECK(IsRtpPacket(rtp_packet)); + return ByteReader<uint16_t>::ReadBigEndian(rtp_packet.data() + 2); +} + +uint32_t ParseRtpSsrc(rtc::ArrayView<const uint8_t> rtp_packet) { + RTC_DCHECK(IsRtpPacket(rtp_packet)); + return ByteReader<uint32_t>::ReadBigEndian(rtp_packet.data() + 8); +} + +} // namespace webrtc |