blob: 245444612faf838d3afacb8741a20b8e57d06b19 [file] [log] [blame]
/*
* Copyright (C) 2016 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.
*/
#define LOG_TAG "SharedRingBuffer"
//#define LOG_NDEBUG 0
#include <utils/Log.h>
#include <sys/mman.h>
#include "binding/RingBufferParcelable.h"
#include "binding/AudioEndpointParcelable.h"
#include "SharedRingBuffer.h"
using namespace android;
using namespace aaudio;
SharedRingBuffer::~SharedRingBuffer()
{
if (mSharedMemory != nullptr) {
delete mFifoBuffer;
munmap(mSharedMemory, mSharedMemorySizeInBytes);
mSharedMemory = nullptr;
}
}
aaudio_result_t SharedRingBuffer::allocate(fifo_frames_t bytesPerFrame,
fifo_frames_t capacityInFrames) {
mCapacityInFrames = capacityInFrames;
// Create shared memory large enough to hold the data and the read and write counters.
mDataMemorySizeInBytes = bytesPerFrame * capacityInFrames;
mSharedMemorySizeInBytes = mDataMemorySizeInBytes + (2 * (sizeof(fifo_counter_t)));
mFileDescriptor.reset(ashmem_create_region("AAudioSharedRingBuffer", mSharedMemorySizeInBytes));
if (mFileDescriptor.get() == -1) {
ALOGE("allocate() ashmem_create_region() failed %d", errno);
return AAUDIO_ERROR_INTERNAL;
}
ALOGV("allocate() mFileDescriptor = %d\n", mFileDescriptor.get());
int err = ashmem_set_prot_region(mFileDescriptor.get(), PROT_READ|PROT_WRITE); // TODO error handling?
if (err < 0) {
ALOGE("allocate() ashmem_set_prot_region() failed %d", errno);
mFileDescriptor.reset();
return AAUDIO_ERROR_INTERNAL; // TODO convert errno to a better AAUDIO_ERROR;
}
// Map the fd to memory addresses.
mSharedMemory = (uint8_t *) mmap(0, mSharedMemorySizeInBytes,
PROT_READ|PROT_WRITE,
MAP_SHARED,
mFileDescriptor.get(), 0);
if (mSharedMemory == MAP_FAILED) {
ALOGE("allocate() mmap() failed %d", errno);
mFileDescriptor.reset();
return AAUDIO_ERROR_INTERNAL; // TODO convert errno to a better AAUDIO_ERROR;
}
// Get addresses for our counters and data from the shared memory.
fifo_counter_t *readCounterAddress =
(fifo_counter_t *) &mSharedMemory[SHARED_RINGBUFFER_READ_OFFSET];
fifo_counter_t *writeCounterAddress =
(fifo_counter_t *) &mSharedMemory[SHARED_RINGBUFFER_WRITE_OFFSET];
uint8_t *dataAddress = &mSharedMemory[SHARED_RINGBUFFER_DATA_OFFSET];
mFifoBuffer = new FifoBuffer(bytesPerFrame, capacityInFrames,
readCounterAddress, writeCounterAddress, dataAddress);
return AAUDIO_OK;
}
void SharedRingBuffer::fillParcelable(AudioEndpointParcelable &endpointParcelable,
RingBufferParcelable &ringBufferParcelable) {
int fdIndex = endpointParcelable.addFileDescriptor(mFileDescriptor, mSharedMemorySizeInBytes);
ringBufferParcelable.setupMemory(fdIndex,
SHARED_RINGBUFFER_DATA_OFFSET,
mDataMemorySizeInBytes,
SHARED_RINGBUFFER_READ_OFFSET,
SHARED_RINGBUFFER_WRITE_OFFSET,
sizeof(fifo_counter_t));
ringBufferParcelable.setBytesPerFrame(mFifoBuffer->getBytesPerFrame());
ringBufferParcelable.setFramesPerBurst(1);
ringBufferParcelable.setCapacityInFrames(mCapacityInFrames);
}