diff options
Diffstat (limited to 'src/AlsaInput.h')
-rw-r--r-- | src/AlsaInput.h | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/src/AlsaInput.h b/src/AlsaInput.h new file mode 100644 index 0000000..b43ad7d --- /dev/null +++ b/src/AlsaInput.h @@ -0,0 +1,90 @@ +/* ------------------------------------------------------------------ + * Copyright (C) 2011 Martin Storsjo + * Copyright (C) 2013,2014 Matthias P. Braendli + * + * 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. + * ------------------------------------------------------------------- + */ + +#ifndef __ALSA_H_ +#define __ALSA_H_ +#include <cstdio> +#include <stdint.h> +#include <string> + +#include <alsa/asoundlib.h> +#include <boost/thread/thread.hpp> + +#include "SampleQueue.h" + +using namespace std; + +// 16 bits per sample is fine for now +#define BYTES_PER_SAMPLE 2 + +// How many samples we insert into the queue each call +#define NUM_SAMPLES_PER_CALL 10 // 10 samples @ 32kHz = 3.125ms + +class AlsaInput +{ + public: + AlsaInput(const string& alsa_dev, + unsigned int channels, + unsigned int rate, + SampleQueue<uint8_t>& queue) : + m_running(false), + m_alsa_dev(alsa_dev), + m_channels(channels), + m_rate(rate), + m_queue(queue), + m_alsa_handle(NULL) { } + + ~AlsaInput() + { + if (m_running) { + m_running = false; + m_thread.interrupt(); + m_thread.join(); + } + + if (m_alsa_handle) { + snd_pcm_abort(m_alsa_handle); + m_alsa_handle = NULL; + } + } + + int prepare(); + + int start(); + + private: + AlsaInput(const AlsaInput& other) : m_queue(other.m_queue) {} + + size_t read(uint8_t* buf, snd_pcm_uframes_t length); + void process(); + + bool m_running; + boost::thread m_thread; + string m_alsa_dev; + unsigned int m_channels; + unsigned int m_rate; + + SampleQueue<uint8_t>& m_queue; + + snd_pcm_t *m_alsa_handle; + +}; + +#endif + |