// as a whole, since that's what AudioMixer::add_audio() wants.
#include <alsa/asoundlib.h>
-
+#include <stdint.h>
+#include <sys/types.h>
#include <atomic>
#include <functional>
+#include <memory>
#include <string>
#include <thread>
-#include <vector>
#include "bmusb/bmusb.h"
-#include "timebase.h"
+
+class ALSAPool;
class ALSAInput {
public:
typedef std::function<bool(const uint8_t *data, unsigned num_samples, bmusb::AudioFormat audio_format, int64_t frame_length)> audio_callback_t;
- ALSAInput(const char *device, unsigned sample_rate, unsigned num_channels, audio_callback_t audio_callback);
+ ALSAInput(const char *device, unsigned sample_rate, unsigned num_channels, audio_callback_t audio_callback, ALSAPool *parent_pool, unsigned internal_dev_index);
~ALSAInput();
+ // If not called before start_capture_thread(), the capture thread
+ // will call it until it succeeds.
+ bool open_device();
+
+ // Not valid before the device has been successfully opened.
// NOTE: Might very well be different from the sample rate given to the
// constructor, since the card might not support the one you wanted.
unsigned get_sample_rate() const { return sample_rate; }
void start_capture_thread();
void stop_capture_thread();
- // TODO: Worry about hotplug.
- struct Device {
- std::string address; // E.g. “hw:0,0”.
- std::string name, info;
- unsigned num_channels;
- };
- static std::vector<Device> enumerate_devices();
+ // Set access, sample rate and format parameters on the given ALSA PCM handle.
+ // Returns the computed parameter set and the chosen sample rate. Note that
+ // sample_rate is an in/out parameter; you send in the desired rate,
+ // and ALSA picks one as close to that as possible.
+ static bool set_base_params(const char *device_name, snd_pcm_t *pcm_handle, snd_pcm_hw_params_t *hw_params, unsigned *sample_rate);
private:
void capture_thread_func();
int64_t frames_to_pts(uint64_t n) const;
- void die_on_error(const char *func_name, int err);
+
+ enum class CaptureEndReason {
+ REQUESTED_QUIT,
+ DEVICE_GONE,
+ OTHER_ERROR
+ };
+ CaptureEndReason do_capture();
std::string device;
unsigned sample_rate, num_channels, num_periods;
bmusb::AudioFormat audio_format;
audio_callback_t audio_callback;
- snd_pcm_t *pcm_handle;
+ snd_pcm_t *pcm_handle = nullptr;
std::thread capture_thread;
std::atomic<bool> should_quit{false};
std::unique_ptr<uint8_t[]> buffer;
+ ALSAPool *parent_pool;
+ unsigned internal_dev_index;
};
#endif // !defined(_ALSA_INPUT_H)