1/*
2 * Copyright 2015 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 FIFO_FIFO_BUFFER_H
18#define FIFO_FIFO_BUFFER_H
19
20#include <stdint.h>
21
22#include "FifoControllerBase.h"
23
24namespace android {
25
26/**
27 * Structure that represents a region in a circular buffer that might be at the
28 * end of the array and split in two.
29 */
30struct WrappingBuffer {
31    enum {
32        SIZE = 2
33    };
34    void *data[SIZE];
35    int32_t numFrames[SIZE];
36};
37
38class FifoBuffer {
39public:
40    FifoBuffer(int32_t bytesPerFrame, fifo_frames_t capacityInFrames);
41
42    FifoBuffer(int32_t bytesPerFrame,
43               fifo_frames_t capacityInFrames,
44               fifo_counter_t *readCounterAddress,
45               fifo_counter_t *writeCounterAddress,
46               void *dataStorageAddress);
47
48    ~FifoBuffer();
49
50    int32_t convertFramesToBytes(fifo_frames_t frames);
51
52    fifo_frames_t read(void *destination, fifo_frames_t framesToRead);
53
54    fifo_frames_t write(const void *source, fifo_frames_t framesToWrite);
55
56    fifo_frames_t getThreshold();
57
58    void setThreshold(fifo_frames_t threshold);
59
60    fifo_frames_t getBufferCapacityInFrames();
61
62    /**
63     * Return pointer to available full frames in data1 and set size in numFrames1.
64     * if the data is split across the end of the FIFO then set data2 and numFrames2.
65     * Other wise set them to null
66     * @param wrappingBuffer
67     */
68    void getFullDataAvailable(WrappingBuffer *wrappingBuffer);
69
70    /**
71     * Return pointer to available empty frames in data1 and set size in numFrames1.
72     * if the room is split across the end of the FIFO then set data2 and numFrames2.
73     * Other wise set them to null
74     * @param wrappingBuffer
75     */
76    void getEmptyRoomAvailable(WrappingBuffer *wrappingBuffer);
77
78    /**
79     * Copy data from the FIFO into the buffer.
80     * @param buffer
81     * @param numFrames
82     * @return
83     */
84    fifo_frames_t readNow(void *buffer, fifo_frames_t numFrames);
85
86    int64_t getNextReadTime(int32_t frameRate);
87
88    int32_t getUnderrunCount() const { return mUnderrunCount; }
89
90    FifoControllerBase *getFifoControllerBase() { return mFifo; }
91
92    int32_t getBytesPerFrame() {
93        return mBytesPerFrame;
94    }
95
96    fifo_counter_t getReadCounter() {
97        return mFifo->getReadCounter();
98    }
99
100    void setReadCounter(fifo_counter_t n) {
101        mFifo->setReadCounter(n);
102    }
103
104    fifo_counter_t getWriteCounter() {
105        return mFifo->getWriteCounter();
106    }
107
108    void setWriteCounter(fifo_counter_t n) {
109        mFifo->setWriteCounter(n);
110    }
111
112private:
113
114    void fillWrappingBuffer(WrappingBuffer *wrappingBuffer,
115                            int32_t framesAvailable, int32_t startIndex);
116
117    const fifo_frames_t mFrameCapacity;
118    const int32_t mBytesPerFrame;
119    uint8_t *mStorage;
120    bool mStorageOwned; // did this object allocate the storage?
121    FifoControllerBase *mFifo;
122    fifo_counter_t mFramesReadCount;
123    fifo_counter_t mFramesUnderrunCount;
124    int32_t mUnderrunCount; // need? just use frames
125    int32_t mLastReadSize;
126};
127
128}  // android
129
130#endif //FIFO_FIFO_BUFFER_H
131