1/*
2 * Copyright (C) 2012 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#define LOG_TAG "SourceAudioBufferProvider"
18//#define LOG_NDEBUG 0
19
20#include <utils/Log.h>
21#include <media/nbaio/SourceAudioBufferProvider.h>
22
23namespace android {
24
25SourceAudioBufferProvider::SourceAudioBufferProvider(const sp<NBAIO_Source>& source) :
26    mSource(source),
27    // mFrameSize below
28    mAllocated(NULL), mSize(0), mOffset(0), mRemaining(0), mGetCount(0), mFramesReleased(0)
29{
30    ALOG_ASSERT(source != 0);
31
32    // negotiate with source
33    NBAIO_Format counterOffers[1];
34    size_t numCounterOffers = 1;
35    ssize_t index = source->negotiate(NULL, 0, counterOffers, numCounterOffers);
36    ALOG_ASSERT(index == (ssize_t) NEGOTIATE && numCounterOffers > 0);
37    numCounterOffers = 0;
38    index = source->negotiate(counterOffers, 1, NULL, numCounterOffers);
39    ALOG_ASSERT(index == 0);
40    mFrameSize = Format_frameSize(source->format());
41}
42
43SourceAudioBufferProvider::~SourceAudioBufferProvider()
44{
45    free(mAllocated);
46}
47
48status_t SourceAudioBufferProvider::getNextBuffer(Buffer *buffer)
49{
50    ALOG_ASSERT(buffer != NULL && buffer->frameCount > 0 && mGetCount == 0);
51    // any leftover data available?
52    if (mRemaining > 0) {
53        ALOG_ASSERT(mOffset + mRemaining <= mSize);
54        if (mRemaining < buffer->frameCount) {
55            buffer->frameCount = mRemaining;
56        }
57        buffer->raw = (char *) mAllocated + (mOffset * mFrameSize);
58        mGetCount = buffer->frameCount;
59        return OK;
60    }
61    // do we need to reallocate?
62    if (buffer->frameCount > mSize) {
63        free(mAllocated);
64        // Android convention is to _not_ check the return value of malloc and friends.
65        // But in this case the calloc() can also fail due to integer overflow,
66        // so we check and recover.
67        mAllocated = calloc(buffer->frameCount, mFrameSize);
68        if (mAllocated == NULL) {
69            mSize = 0;
70            goto fail;
71        }
72        mSize = buffer->frameCount;
73    }
74    {
75        // read from source
76        ssize_t actual = mSource->read(mAllocated, buffer->frameCount);
77        if (actual > 0) {
78            ALOG_ASSERT((size_t) actual <= buffer->frameCount);
79            mOffset = 0;
80            mRemaining = actual;
81            buffer->raw = mAllocated;
82            buffer->frameCount = actual;
83            mGetCount = actual;
84            return OK;
85        }
86    }
87fail:
88    buffer->raw = NULL;
89    buffer->frameCount = 0;
90    mGetCount = 0;
91    return NOT_ENOUGH_DATA;
92}
93
94void SourceAudioBufferProvider::releaseBuffer(Buffer *buffer)
95{
96    ALOG_ASSERT((buffer != NULL) &&
97            (buffer->raw == (char *) mAllocated + (mOffset * mFrameSize)) &&
98            (buffer->frameCount <= mGetCount) &&
99            (mGetCount <= mRemaining) &&
100            (mOffset + mRemaining <= mSize));
101    mOffset += buffer->frameCount;
102    mRemaining -= buffer->frameCount;
103    mFramesReleased += buffer->frameCount;
104    buffer->raw = NULL;
105    buffer->frameCount = 0;
106    mGetCount = 0;
107}
108
109size_t SourceAudioBufferProvider::framesReady() const
110{
111    ssize_t avail = mSource->availableToRead();
112    return avail < 0 ? 0 : (size_t) avail;
113}
114
115int64_t SourceAudioBufferProvider::framesReleased() const
116{
117    return mFramesReleased;
118}
119
120void SourceAudioBufferProvider::onTimestamp(const ExtendedTimestamp &timestamp)
121{
122    mSource->onTimestamp(timestamp);
123}
124
125}   // namespace android
126