gecko-dev/media/mtransport/transportlayer.h

139 lines
3.6 KiB
C++

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at http://mozilla.org/MPL/2.0/. */
// Original author: ekr@rtfm.com
#ifndef transportlayer_h__
#define transportlayer_h__
#include "sigslot.h"
#include "mozilla/DebugOnly.h"
#include "mozilla/RefPtr.h"
#include "nsCOMPtr.h"
#include "nsIEventTarget.h"
#include "nsThreadUtils.h"
#include "m_cpp_utils.h"
namespace mozilla {
class TransportFlow;
typedef int TransportResult;
enum {
TE_WOULDBLOCK = -1, TE_ERROR = -2, TE_INTERNAL = -3
};
#define TRANSPORT_LAYER_ID(name) \
virtual const std::string id() { return name; } \
static std::string ID() { return name; }
// Abstract base class for network transport layers.
class TransportLayer : public sigslot::has_slots<> {
public:
// The state of the transport flow
// We can't use "ERROR" because Windows has a macro named "ERROR"
enum State { TS_NONE, TS_INIT, TS_CONNECTING, TS_OPEN, TS_CLOSED, TS_ERROR };
enum Mode { STREAM, DGRAM };
// Is this a stream or datagram flow
TransportLayer(Mode mode = STREAM) :
mode_(mode),
state_(TS_NONE),
flow_id_(),
downward_(nullptr) {}
virtual ~TransportLayer() {}
// Called to initialize
nsresult Init(); // Called by Insert() to set up -- do not override
virtual nsresult InitInternal() { return NS_OK; } // Called by Init
// Called when inserted into a flow
virtual void Inserted(TransportFlow *flow, TransportLayer *downward);
// Downward interface
TransportLayer *downward() { return downward_; }
// Dispatch a call onto our thread (or run on the same thread if
// thread is not set). This is always synchronous.
nsresult RunOnThread(nsIRunnable *event) {
if (target_) {
nsIThread *thr;
DebugOnly<nsresult> rv = NS_GetCurrentThread(&thr);
MOZ_ASSERT(NS_SUCCEEDED(rv));
if (target_ != thr) {
return target_->Dispatch(event, NS_DISPATCH_SYNC);
}
}
return event->Run();
}
// Get the state
State state() const { return state_; }
// Must be implemented by derived classes
virtual TransportResult SendPacket(const unsigned char *data, size_t len) = 0;
// Get the thread.
const nsCOMPtr<nsIEventTarget> GetThread() const {
return target_;
}
// Event definitions that one can register for
// State has changed
sigslot::signal2<TransportLayer*, State> SignalStateChange;
// Data received on the flow
sigslot::signal3<TransportLayer*, const unsigned char *, size_t>
SignalPacketReceived;
// Return the layer id for this layer
virtual const std::string id() = 0;
// The id of the flow
const std::string& flow_id() {
return flow_id_;
}
protected:
virtual void WasInserted() {}
virtual void SetState(State state);
// Check if we are on the right thread
void CheckThread() {
NS_ABORT_IF_FALSE(CheckThreadInt(), "Wrong thread");
}
Mode mode_;
State state_;
std::string flow_id_;
TransportLayer *downward_; // The next layer in the stack
nsCOMPtr<nsIEventTarget> target_;
private:
DISALLOW_COPY_ASSIGN(TransportLayer);
bool CheckThreadInt() {
bool on;
if (!target_) // OK if no thread set.
return true;
NS_ENSURE_SUCCESS(target_->IsOnCurrentThread(&on), false);
NS_ENSURE_TRUE(on, false);
return true;
}
};
#define LAYER_INFO "Flow[" << flow_id() << "(none)" << "]; Layer[" << id() << "]: "
} // close namespace
#endif