blob: 53c11d4291a62965162519a75f1ec0bff1c9df13 [file] [log] [blame]
* Copyright 2012 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.
// This file contains interfaces for DataChannels
#include <string>
#include "webrtc/base/basictypes.h"
#include "webrtc/base/checks.h"
#include "webrtc/base/copyonwritebuffer.h"
#include "webrtc/base/refcount.h"
namespace webrtc {
struct DataChannelInit {
: reliable(false),
id(-1) {
bool reliable; // Deprecated.
bool ordered; // True if ordered delivery is required.
int maxRetransmitTime; // The max period of time in milliseconds in which
// retransmissions will be sent. After this time, no
// more retransmissions will be sent. -1 if unset.
int maxRetransmits; // The max number of retransmissions. -1 if unset.
std::string protocol; // This is set by the application and opaque to the
// WebRTC implementation.
bool negotiated; // True if the channel has been externally negotiated
// and we do not send an in-band signalling in the
// form of an "open" message.
int id; // The stream id, or SID, for SCTP data channels. -1
// if unset.
struct DataBuffer {
DataBuffer(const rtc::CopyOnWriteBuffer& data, bool binary)
: data(data),
binary(binary) {
// For convenience for unit tests.
explicit DataBuffer(const std::string& text)
: data(, text.length()),
binary(false) {
size_t size() const { return data.size(); }
rtc::CopyOnWriteBuffer data;
// Indicates if the received data contains UTF-8 or binary data.
// Note that the upper layers are left to verify the UTF-8 encoding.
// TODO(jiayl): prefer to use an enum instead of a bool.
bool binary;
class DataChannelObserver {
// The data channel state have changed.
virtual void OnStateChange() = 0;
// A data buffer was successfully received.
virtual void OnMessage(const DataBuffer& buffer) = 0;
// The data channel's buffered_amount has changed.
virtual void OnBufferedAmountChange(uint64_t previous_amount){};
virtual ~DataChannelObserver() {}
class DataChannelInterface : public rtc::RefCountInterface {
// Keep in sync with and
// RTCDataChannel.h:RTCDataChannelState.
enum DataState {
kOpen, // The DataChannel is ready to send data.
static const char* DataStateString(DataState state) {
switch (state) {
case kConnecting:
return "connecting";
case kOpen:
return "open";
case kClosing:
return "closing";
case kClosed:
return "closed";
RTC_CHECK(false) << "Unknown DataChannel state: " << state;
return "";
virtual void RegisterObserver(DataChannelObserver* observer) = 0;
virtual void UnregisterObserver() = 0;
// The label attribute represents a label that can be used to distinguish this
// DataChannel object from other DataChannel objects.
virtual std::string label() const = 0;
virtual bool reliable() const = 0;
// TODO(tommyw): Remove these dummy implementations when all classes have
// implemented these APIs. They should all just return the values the
// DataChannel was created with.
virtual bool ordered() const { return false; }
virtual uint16_t maxRetransmitTime() const { return 0; }
virtual uint16_t maxRetransmits() const { return 0; }
virtual std::string protocol() const { return std::string(); }
virtual bool negotiated() const { return false; }
virtual int id() const = 0;
virtual DataState state() const = 0;
// The buffered_amount returns the number of bytes of application data
// (UTF-8 text and binary data) that have been queued using SendBuffer but
// have not yet been transmitted to the network.
virtual uint64_t buffered_amount() const = 0;
virtual void Close() = 0;
// Sends |data| to the remote peer.
virtual bool Send(const DataBuffer& buffer) = 0;
virtual ~DataChannelInterface() {}
} // namespace webrtc