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// Copyright (c) 2010 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "media/audio/linux/alsa_util.h"
#include <string>
#include "base/logging.h"
#include "media/audio/linux/alsa_wrapper.h"
namespace {
snd_pcm_t* OpenDevice(AlsaWrapper* wrapper,
const char* device_name,
snd_pcm_stream_t type,
int channels,
int sample_rate,
snd_pcm_format_t pcm_format,
int latency_us) {
snd_pcm_t* handle = NULL;
int error = wrapper->PcmOpen(&handle, device_name, type, SND_PCM_NONBLOCK);
if (error < 0) {
LOG(WARNING) << "PcmOpen: " << device_name << ","
<< wrapper->StrError(error);
return NULL;
}
error = wrapper->PcmSetParams(handle, pcm_format,
SND_PCM_ACCESS_RW_INTERLEAVED, channels,
sample_rate, 1, latency_us);
if (error < 0) {
LOG(WARNING) << "PcmSetParams: " << device_name << ", "
<< wrapper->StrError(error) << " - Format: " << pcm_format
<< " Channels: " << channels << " Latency: " << latency_us;
if (!alsa_util::CloseDevice(wrapper, handle)) {
// TODO(ajwong): Retry on certain errors?
LOG(WARNING) << "Unable to close audio device. Leaking handle.";
}
return NULL;
}
return handle;
}
} // namespace
namespace alsa_util {
snd_pcm_format_t BitsToFormat(int bits_per_sample) {
switch (bits_per_sample) {
case 8:
return SND_PCM_FORMAT_U8;
case 16:
return SND_PCM_FORMAT_S16;
case 24:
return SND_PCM_FORMAT_S24;
case 32:
return SND_PCM_FORMAT_S32;
default:
return SND_PCM_FORMAT_UNKNOWN;
}
}
int CloseDevice(AlsaWrapper* wrapper, snd_pcm_t* handle) {
std::string device_name = wrapper->PcmName(handle);
int error = wrapper->PcmClose(handle);
if (error < 0) {
LOG(ERROR) << "PcmClose: " << device_name << ", "
<< wrapper->StrError(error);
}
return error;
}
snd_pcm_t* OpenCaptureDevice(AlsaWrapper* wrapper,
const char* device_name,
int channels,
int sample_rate,
snd_pcm_format_t pcm_format,
int latency_us) {
return OpenDevice(wrapper, device_name, SND_PCM_STREAM_CAPTURE, channels,
sample_rate, pcm_format, latency_us);
}
snd_pcm_t* OpenPlaybackDevice(AlsaWrapper* wrapper,
const char* device_name,
int channels,
int sample_rate,
snd_pcm_format_t pcm_format,
int latency_us) {
return OpenDevice(wrapper, device_name, SND_PCM_STREAM_PLAYBACK, channels,
sample_rate, pcm_format, latency_us);
}
} // namespace alsa_util
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