replicant-frameworks_native/include/ui/InputTransport.h
Jeff Brown 6cdee9831d Rewrite input transport using sockets.
Since we will not longer be modifying events in place, we don't need
to use an ashmem region for input.  Simplified the code to instead
use a socket of type SOCK_SEQPACKET.

This is part of a series of changes to improve input system pipelining.

Bug: 5963420

Change-Id: I05909075ed8b61b93900913e44c6db84857340d8
2012-02-13 10:28:40 -08:00

278 lines
8.6 KiB
C++

/*
* Copyright (C) 2010 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef _UI_INPUT_TRANSPORT_H
#define _UI_INPUT_TRANSPORT_H
/**
* Native input transport.
*
* The InputChannel provides a mechanism for exchanging InputMessage structures across processes.
*
* The InputPublisher and InputConsumer each handle one end-point of an input channel.
* The InputPublisher is used by the input dispatcher to send events to the application.
* The InputConsumer is used by the application to receive events from the input dispatcher.
*/
#include <ui/Input.h>
#include <utils/Errors.h>
#include <utils/Timers.h>
#include <utils/RefBase.h>
#include <utils/String8.h>
namespace android {
/*
* Intermediate representation used to send input events and related signals.
*/
struct InputMessage {
enum {
TYPE_KEY = 1,
TYPE_MOTION = 2,
TYPE_FINISHED = 3,
};
struct Header {
uint32_t type;
uint32_t padding; // 8 byte alignment for the body that follows
} header;
union Body {
struct Key {
nsecs_t eventTime;
int32_t deviceId;
int32_t source;
int32_t action;
int32_t flags;
int32_t keyCode;
int32_t scanCode;
int32_t metaState;
int32_t repeatCount;
nsecs_t downTime;
inline size_t size() const {
return sizeof(Key);
}
} key;
struct Motion {
nsecs_t eventTime;
int32_t deviceId;
int32_t source;
int32_t action;
int32_t flags;
int32_t metaState;
int32_t buttonState;
int32_t edgeFlags;
nsecs_t downTime;
float xOffset;
float yOffset;
float xPrecision;
float yPrecision;
size_t pointerCount;
struct Pointer {
PointerProperties properties;
PointerCoords coords;
} pointers[MAX_POINTERS];
inline size_t size() const {
return sizeof(Motion) - sizeof(Pointer) * MAX_POINTERS
+ sizeof(Pointer) * pointerCount;
}
} motion;
struct Finished {
bool handled;
inline size_t size() const {
return sizeof(Finished);
}
} finished;
} body;
bool isValid(size_t actualSize) const;
size_t size() const;
};
/*
* An input channel consists of a local unix domain socket used to send and receive
* input messages across processes. Each channel has a descriptive name for debugging purposes.
*
* Each endpoint has its own InputChannel object that specifies its file descriptor.
*
* The input channel is closed when all references to it are released.
*/
class InputChannel : public RefBase {
protected:
virtual ~InputChannel();
public:
InputChannel(const String8& name, int32_t fd);
/* Creates a pair of input channels.
*
* Returns OK on success.
*/
static status_t openInputChannelPair(const String8& name,
sp<InputChannel>& outServerChannel, sp<InputChannel>& outClientChannel);
inline String8 getName() const { return mName; }
inline int32_t getFd() const { return mFd; }
/* Sends a message to the other endpoint.
*
* If the channel is full then the message is guaranteed not to have been sent at all.
* Try again after the consumer has sent a finished signal indicating that it has
* consumed some of the pending messages from the channel.
*
* Returns OK on success.
* Returns WOULD_BLOCK if the channel is full.
* Returns DEAD_OBJECT if the channel's peer has been closed.
* Other errors probably indicate that the channel is broken.
*/
status_t sendMessage(const InputMessage* msg);
/* Receives a message sent by the other endpoint.
*
* If there is no message present, try again after poll() indicates that the fd
* is readable.
*
* Returns OK on success.
* Returns WOULD_BLOCK if there is no message present.
* Returns DEAD_OBJECT if the channel's peer has been closed.
* Other errors probably indicate that the channel is broken.
*/
status_t receiveMessage(InputMessage* msg);
private:
String8 mName;
int32_t mFd;
};
/*
* Publishes input events to an input channel.
*/
class InputPublisher {
public:
/* Creates a publisher associated with an input channel. */
explicit InputPublisher(const sp<InputChannel>& channel);
/* Destroys the publisher and releases its input channel. */
~InputPublisher();
/* Gets the underlying input channel. */
inline sp<InputChannel> getChannel() { return mChannel; }
/* Publishes a key event to the input channel.
*
* Returns OK on success.
* Returns WOULD_BLOCK if the channel is full.
* Returns DEAD_OBJECT if the channel's peer has been closed.
* Other errors probably indicate that the channel is broken.
*/
status_t publishKeyEvent(
int32_t deviceId,
int32_t source,
int32_t action,
int32_t flags,
int32_t keyCode,
int32_t scanCode,
int32_t metaState,
int32_t repeatCount,
nsecs_t downTime,
nsecs_t eventTime);
/* Publishes a motion event to the input channel.
*
* Returns OK on success.
* Returns WOULD_BLOCK if the channel is full.
* Returns DEAD_OBJECT if the channel's peer has been closed.
* Returns BAD_VALUE if pointerCount is less than 1 or greater than MAX_POINTERS.
* Other errors probably indicate that the channel is broken.
*/
status_t publishMotionEvent(
int32_t deviceId,
int32_t source,
int32_t action,
int32_t flags,
int32_t edgeFlags,
int32_t metaState,
int32_t buttonState,
float xOffset,
float yOffset,
float xPrecision,
float yPrecision,
nsecs_t downTime,
nsecs_t eventTime,
size_t pointerCount,
const PointerProperties* pointerProperties,
const PointerCoords* pointerCoords);
/* Receives the finished signal from the consumer in reply to the original dispatch signal.
* Returns whether the consumer handled the message.
*
* Returns OK on success.
* Returns WOULD_BLOCK if there is no signal present.
* Returns DEAD_OBJECT if the channel's peer has been closed.
* Other errors probably indicate that the channel is broken.
*/
status_t receiveFinishedSignal(bool* outHandled);
private:
sp<InputChannel> mChannel;
};
/*
* Consumes input events from an input channel.
*/
class InputConsumer {
public:
/* Creates a consumer associated with an input channel. */
explicit InputConsumer(const sp<InputChannel>& channel);
/* Destroys the consumer and releases its input channel. */
~InputConsumer();
/* Gets the underlying input channel. */
inline sp<InputChannel> getChannel() { return mChannel; }
/* Consumes an input event from the input channel and copies its contents into
* an InputEvent object created using the specified factory.
*
* Returns OK on success.
* Returns WOULD_BLOCK if there is no event present.
* Returns DEAD_OBJECT if the channel's peer has been closed.
* Returns NO_MEMORY if the event could not be created.
* Other errors probably indicate that the channel is broken.
*/
status_t consume(InputEventFactoryInterface* factory, InputEvent** outEvent);
/* Sends a finished signal to the publisher to inform it that the current message is
* finished processing and specifies whether the message was handled by the consumer.
*
* Returns OK on success.
* Other errors probably indicate that the channel is broken.
*/
status_t sendFinishedSignal(bool handled);
private:
sp<InputChannel> mChannel;
};
} // namespace android
#endif // _UI_INPUT_TRANSPORT_H