audio_a2dp_hw: add device lock am: 24012515

struct a2dp_stream_out;

struct a2dp_audio_device {

  // Important: device must be first as an audio_hw_device* may be cast to

  // a2dp_audio_device* when the type is implicitly known.

  struct audio_hw_device device;

  std::recursive_mutex* mutex;  // See note below on mutex acquisition order.

  struct a2dp_stream_in* input;

  struct a2dp_stream_out* output;

};

/* move ctrl_fd outside output stream and keep open until HAL unloaded ? */

struct a2dp_stream_common {

  std::recursive_mutex* mutex;

  std::recursive_mutex* mutex;  // See note below on mutex acquisition order.

  int ctrl_fd;

  int audio_fd;

  size_t buffer_sz;

  struct a2dp_stream_common common;

};

/*

 * Mutex acquisition order:

 *

 * The a2dp_audio_device (adev) mutex must be acquired before

 * the a2dp_stream_common (out or in) mutex.

 *

 * This may differ from other audio HALs.

 */

/*****************************************************************************

 *  Static variables

 *****************************************************************************/

  int ret = 0;

  INFO("opening output");

  // protect against adev->output and stream_out from being inconsistent

  std::lock_guard<std::recursive_mutex> lock(*a2dp_dev->mutex);

  out = (struct a2dp_stream_out*)calloc(1, sizeof(struct a2dp_stream_out));

  if (!out) return -ENOMEM;

  struct a2dp_audio_device* a2dp_dev = (struct a2dp_audio_device*)dev;

  struct a2dp_stream_out* out = (struct a2dp_stream_out*)stream;

  INFO("closing output (state %d)", out->common.state);

  std::unique_lock<std::recursive_mutex> lock(*out->common.mutex);

  if ((out->common.state == AUDIO_A2DP_STATE_STARTED) ||

      (out->common.state == AUDIO_A2DP_STATE_STOPPING)) {

  // prevent interference with adev_set_parameters.

  std::lock_guard<std::recursive_mutex> lock(*a2dp_dev->mutex);

  {

    std::lock_guard<std::recursive_mutex> lock(*out->common.mutex);

    const a2dp_state_t state = out->common.state;

    INFO("closing output (state %d)", (int)state);

    if ((state == AUDIO_A2DP_STATE_STARTED) ||

        (state == AUDIO_A2DP_STATE_STOPPING)) {

      stop_audio_datapath(&out->common);

    }

    skt_disconnect(out->common.ctrl_fd);

    out->common.ctrl_fd = AUDIO_SKT_DISCONNECTED;

  lock.unlock();

  }

  a2dp_stream_common_destroy(&out->common);

  free(stream);

  a2dp_dev->output = NULL;

static int adev_set_parameters(struct audio_hw_device* dev,

                               const char* kvpairs) {

  struct a2dp_audio_device* a2dp_dev = (struct a2dp_audio_device*)dev;

  struct a2dp_stream_out* out = a2dp_dev->output;

  int retval = 0;

  // prevent interference with adev_close_output_stream

  std::lock_guard<std::recursive_mutex> lock(*a2dp_dev->mutex);

  struct a2dp_stream_out* out = a2dp_dev->output;

  if (out == NULL) return retval;

  INFO("state %d", out->common.state);

  FNLOG();

  // protect against adev->input and stream_in from being inconsistent

  std::lock_guard<std::recursive_mutex> lock(*a2dp_dev->mutex);

  in = (struct a2dp_stream_in*)calloc(1, sizeof(struct a2dp_stream_in));

  if (!in) return -ENOMEM;

                                    struct audio_stream_in* stream) {

  struct a2dp_audio_device* a2dp_dev = (struct a2dp_audio_device*)dev;

  struct a2dp_stream_in* in = (struct a2dp_stream_in*)stream;

  a2dp_state_t state = in->common.state;

  INFO("closing input (state %d)", state);

  std::lock_guard<std::recursive_mutex> lock(*a2dp_dev->mutex);

  {

    std::lock_guard<std::recursive_mutex> lock(*in->common.mutex);

    const a2dp_state_t state = in->common.state;

    INFO("closing input (state %d)", (int)state);

    if ((state == AUDIO_A2DP_STATE_STARTED) ||

        (state == AUDIO_A2DP_STATE_STOPPING))

    skt_disconnect(in->common.ctrl_fd);

    in->common.ctrl_fd = AUDIO_SKT_DISCONNECTED;

  }

  a2dp_stream_common_destroy(&in->common);

  free(stream);

  a2dp_dev->input = NULL;

}

static int adev_close(hw_device_t* device) {

  struct a2dp_audio_device* a2dp_dev = (struct a2dp_audio_device*)device;

  FNLOG();

  delete a2dp_dev->mutex;

  a2dp_dev->mutex = nullptr;

  free(device);

  return 0;

}

  if (!adev) return -ENOMEM;

  adev->mutex = new std::recursive_mutex;

  adev->device.common.tag = HARDWARE_DEVICE_TAG;

  adev->device.common.version = AUDIO_DEVICE_API_VERSION_2_0;

  adev->device.common.module = (struct hw_module_t*)module;