MessageQueue.h revision 8aedd4737d6ce8548d2fd5def65b1e1737283821 
1/*
2 * Copyright (C) 2009 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef ANDROID_MESSAGE_QUEUE_H
18#define ANDROID_MESSAGE_QUEUE_H
19
20#include <stdint.h>
21#include <errno.h>
22#include <sys/types.h>
23
24#include <utils/threads.h>
25#include <utils/Timers.h>
26#include <utils/Looper.h>
27
28#include <gui/DisplayEventReceiver.h>
29
30#include "Barrier.h"
31
32namespace android {
33
34class IDisplayEventConnection;
35class EventThread;
36
37// ---------------------------------------------------------------------------
38
39class MessageBase : public MessageHandler
40{
41public:
42    MessageBase();
43
44    // return true if message has a handler
45    virtual bool handler() = 0;
46
47    // waits for the handler to be processed
48    void wait() const { barrier.wait(); }
49
50protected:
51    virtual ~MessageBase();
52
53private:
54    virtual void handleMessage(const Message& message);
55
56    mutable Barrier barrier;
57};
58
59// ---------------------------------------------------------------------------
60
61class MessageQueue {
62    sp<Looper> mLooper;
63    sp<EventThread> mEventThread;
64    sp<IDisplayEventConnection> mEvents;
65    sp<BitTube> mEventTube;
66    int32_t mWorkPending;
67
68    static int cb_eventReceiver(int fd, int events, void* data);
69    int eventReceiver(int fd, int events);
70    ssize_t getEvents(DisplayEventReceiver::Event* events, size_t count);
71    void scheduleWorkASAP();
72
73public:
74    MessageQueue();
75    ~MessageQueue();
76    void setEventThread(const sp<EventThread>& events);
77
78    void waitMessage();
79    status_t postMessage(const sp<MessageBase>& message, nsecs_t reltime=0);
80    status_t invalidate();
81};
82
83// ---------------------------------------------------------------------------
84
85}; // namespace android
86
87#endif /* ANDROID_MESSAGE_QUEUE_H */
88