IConsumerListener.h revision 8dc55396fc9bc425b5e2c82e76a38080f2a655ff 
1/*
2 * Copyright (C) 2013 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_GUI_ICONSUMERLISTENER_H
18#define ANDROID_GUI_ICONSUMERLISTENER_H
19
20#include <stdint.h>
21#include <sys/types.h>
22
23#include <utils/Errors.h>
24#include <utils/RefBase.h>
25
26#include <binder/IInterface.h>
27
28namespace android {
29// ----------------------------------------------------------------------------
30
31class BufferItem;
32
33// ConsumerListener is the interface through which the BufferQueue notifies
34// the consumer of events that the consumer may wish to react to.  Because
35// the consumer will generally have a mutex that is locked during calls from
36// the consumer to the BufferQueue, these calls from the BufferQueue to the
37// consumer *MUST* be called only when the BufferQueue mutex is NOT locked.
38
39class ConsumerListener : public virtual RefBase {
40public:
41    ConsumerListener() { }
42    virtual ~ConsumerListener() { }
43
44    // onFrameAvailable is called from queueBuffer each time an additional
45    // frame becomes available for consumption. This means that frames that
46    // are queued while in asynchronous mode only trigger the callback if no
47    // previous frames are pending. Frames queued while in synchronous mode
48    // always trigger the callback. The item passed to the callback will contain
49    // all of the information about the queued frame except for its
50    // GraphicBuffer pointer, which will always be null.
51    //
52    // This is called without any lock held and can be called concurrently
53    // by multiple threads.
54    virtual void onFrameAvailable(const BufferItem& item) = 0; /* Asynchronous */
55
56    // onFrameReplaced is called from queueBuffer if the frame being queued is
57    // replacing an existing slot in the queue. Any call to queueBuffer that
58    // doesn't call onFrameAvailable will call this callback instead. The item
59    // passed to the callback will contain all of the information about the
60    // queued frame except for its GraphicBuffer pointer, which will always be
61    // null.
62    //
63    // This is called without any lock held and can be called concurrently
64    // by multiple threads.
65    virtual void onFrameReplaced(const BufferItem& item) {} /* Asynchronous */
66
67    // onBuffersReleased is called to notify the buffer consumer that the
68    // BufferQueue has released its references to one or more GraphicBuffers
69    // contained in its slots.  The buffer consumer should then call
70    // BufferQueue::getReleasedBuffers to retrieve the list of buffers
71    //
72    // This is called without any lock held and can be called concurrently
73    // by multiple threads.
74    virtual void onBuffersReleased() = 0; /* Asynchronous */
75
76    // onSidebandStreamChanged is called to notify the buffer consumer that the
77    // BufferQueue's sideband buffer stream has changed. This is called when a
78    // stream is first attached and when it is either detached or replaced by a
79    // different stream.
80    virtual void onSidebandStreamChanged() = 0; /* Asynchronous */
81};
82
83
84class IConsumerListener : public ConsumerListener, public IInterface
85{
86public:
87    DECLARE_META_INTERFACE(ConsumerListener);
88};
89
90// ----------------------------------------------------------------------------
91
92class BnConsumerListener : public BnInterface<IConsumerListener>
93{
94public:
95    virtual status_t    onTransact( uint32_t code,
96                                    const Parcel& data,
97                                    Parcel* reply,
98                                    uint32_t flags = 0);
99};
100
101// ----------------------------------------------------------------------------
102}; // namespace android
103
104#endif // ANDROID_GUI_ICONSUMERLISTENER_H
105