blob: 596812d26a2a36b7a0c4e27a5f36808c55433fe9 [file] [log] [blame]
* Copyright 2004 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 "webrtc/rtc_base/constructormagic.h"
#include "webrtc/rtc_base/dscp.h"
#include "webrtc/rtc_base/sigslot.h"
#include "webrtc/rtc_base/socket.h"
#include "webrtc/rtc_base/timeutils.h"
namespace rtc {
// This structure holds the info needed to update the packet send time header
// extension, including the information needed to update the authentication tag
// after changing the value.
struct PacketTimeUpdateParams {
int rtp_sendtime_extension_id; // extension header id present in packet.
std::vector<char> srtp_auth_key; // Authentication key.
int srtp_auth_tag_len; // Authentication tag length.
int64_t srtp_packet_index; // Required for Rtp Packet authentication.
// This structure holds meta information for the packet which is about to send
// over network.
struct PacketOptions {
PacketOptions() : dscp(DSCP_NO_CHANGE), packet_id(-1) {}
explicit PacketOptions(DiffServCodePoint dscp) : dscp(dscp), packet_id(-1) {}
DiffServCodePoint dscp;
int packet_id; // 16 bits, -1 represents "not set".
PacketTimeUpdateParams packet_time_params;
// This structure will have the information about when packet is actually
// received by socket.
struct PacketTime {
PacketTime() : timestamp(-1), not_before(-1) {}
PacketTime(int64_t timestamp, int64_t not_before)
: timestamp(timestamp), not_before(not_before) {}
int64_t timestamp; // Receive time after socket delivers the data.
// Earliest possible time the data could have arrived, indicating the
// potential error in the |timestamp| value, in case the system, is busy. For
// example, the time of the last select() call.
// If unknown, this value will be set to zero.
int64_t not_before;
inline PacketTime CreatePacketTime(int64_t not_before) {
return PacketTime(TimeMicros(), not_before);
// Provides the ability to receive packets asynchronously. Sends are not
// buffered since it is acceptable to drop packets under high load.
class AsyncPacketSocket : public sigslot::has_slots<> {
enum State {
~AsyncPacketSocket() override;
// Returns current local address. Address may be set to null if the
// socket is not bound yet (GetState() returns STATE_BINDING).
virtual SocketAddress GetLocalAddress() const = 0;
// Returns remote address. Returns zeroes if this is not a client TCP socket.
virtual SocketAddress GetRemoteAddress() const = 0;
// Send a packet.
virtual int Send(const void *pv, size_t cb, const PacketOptions& options) = 0;
virtual int SendTo(const void *pv, size_t cb, const SocketAddress& addr,
const PacketOptions& options) = 0;
// Close the socket.
virtual int Close() = 0;
// Returns current state of the socket.
virtual State GetState() const = 0;
// Get/set options.
virtual int GetOption(Socket::Option opt, int* value) = 0;
virtual int SetOption(Socket::Option opt, int value) = 0;
// Get/Set current error.
// TODO: Remove SetError().
virtual int GetError() const = 0;
virtual void SetError(int error) = 0;
// Emitted each time a packet is read. Used only for UDP and
// connected TCP sockets.
sigslot::signal5<AsyncPacketSocket*, const char*, size_t,
const SocketAddress&,
const PacketTime&> SignalReadPacket;
// Emitted each time a packet is sent.
sigslot::signal2<AsyncPacketSocket*, const SentPacket&> SignalSentPacket;
// Emitted when the socket is currently able to send.
sigslot::signal1<AsyncPacketSocket*> SignalReadyToSend;
// Emitted after address for the socket is allocated, i.e. binding
// is finished. State of the socket is changed from BINDING to BOUND
// (for UDP and server TCP sockets) or CONNECTING (for client TCP
// sockets).
sigslot::signal2<AsyncPacketSocket*, const SocketAddress&> SignalAddressReady;
// Emitted for client TCP sockets when state is changed from
sigslot::signal1<AsyncPacketSocket*> SignalConnect;
// Emitted for client TCP sockets when state is changed from
sigslot::signal2<AsyncPacketSocket*, int> SignalClose;
// Used only for listening TCP sockets.
sigslot::signal2<AsyncPacketSocket*, AsyncPacketSocket*> SignalNewConnection;
} // namespace rtc