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livetrax/libs/backends/alsa/zita-alsa-pcmi.h
Robin Gareus 2326fb1638
ALSA: only read/clear user-requested nperiods before snd_pcm_start
This should fix excessive latency with the RayDay that
has a fixed buffersize of 16384 samples.
2020-05-01 23:17:31 +02:00

193 lines
6.0 KiB
C++

// ----------------------------------------------------------------------------
//
// Copyright (C) 2006-2012 Fons Adriaensen <fons@linuxaudio.org>
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
//
// ----------------------------------------------------------------------------
#ifndef _ZITA_ALSA_PCMI_H_
#define _ZITA_ALSA_PCMI_H_
#define ALSA_PCM_NEW_HW_PARAMS_API
#define ALSA_PCM_NEW_SW_PARAMS_API
#include <alsa/asoundlib.h>
#define ZITA_ALSA_PCMI_MAJOR_VERSION 0
#define ZITA_ALSA_PCMI_MINOR_VERSION 2
#include <stdint.h>
extern int zita_alsa_pcmi_major_version (void);
extern int zita_alsa_pcmi_minor_version (void);
class Alsa_pcmi
{
public:
Alsa_pcmi (
const char *play_name,
const char *capt_name,
const char *ctrl_name,
unsigned int rate,
unsigned int frsize,
unsigned int play_nfrags,
unsigned int capt_nfrags,
unsigned int debug = 0);
~Alsa_pcmi (void);
enum
{
DEBUG_INIT = 1,
DEBUG_STAT = 2,
DEBUG_WAIT = 4,
DEBUG_DATA = 8,
DEBUG_ALL = 15,
FORCE_16B = 256,
FORCE_2CH = 512
};
void printinfo (void);
int pcm_start (void);
int pcm_stop (void);
snd_pcm_sframes_t pcm_wait (void);
int pcm_idle (int len);
int play_init (snd_pcm_uframes_t len);
void clear_chan (int chan, int len);
void play_chan (int chan, const float *src, int len, int step = 1);
int play_done (int len);
int capt_init (snd_pcm_uframes_t len);
void capt_chan (int chan, float *dst, int len, int step = 1);
int capt_done (int len);
int play_avail (void)
{
return snd_pcm_avail (_play_handle);
}
int capt_avail (void)
{
return snd_pcm_avail (_capt_handle);
}
int play_delay (void)
{
long k;
snd_pcm_delay (_play_handle, &k);
return k;
}
int capt_delay (void)
{
long k;
snd_pcm_delay (_capt_handle, &k);
return k;
}
float play_xrun (void) const { return _play_xrun; }
float capt_xrun (void) const { return _capt_xrun; }
int state (void) const { return _state; }
size_t fsize (void) const { return _fsize; }
uint32_t fsamp (void) const { return _fsamp; }
uint32_t play_nfrag (void) const { return _play_nfrag; }
uint32_t capt_nfrag (void) const { return _capt_nfrag; }
uint32_t nplay (void) const { return _play_nchan; }
uint32_t ncapt (void) const { return _capt_nchan; }
snd_pcm_t *play_handle (void) const { return _play_handle; }
snd_pcm_t *capt_handle (void) const { return _capt_handle; }
private:
typedef char *(Alsa_pcmi::*clear_function)(char *, int);
typedef char *(Alsa_pcmi::*play_function)(const float *, char *, int, int);
typedef const char *(Alsa_pcmi::*capt_function) (const char *, float *, int, int);
enum { MAXPFD = 16, MAXCHAN = 128 };
void initialise (const char *play_name, const char *capt_name, const char *ctrl_name);
int set_hwpar (snd_pcm_t *handle, snd_pcm_hw_params_t *hwpar, const char *sname, unsigned int nfrag, unsigned int *nchan);
int set_swpar (snd_pcm_t *handle, snd_pcm_sw_params_t *swpar, const char *sname);
int recover (void);
float xruncheck (snd_pcm_status_t *stat);
char *clear_32 (char *dst, int nfrm);
char *clear_24 (char *dst, int nfrm);
char *clear_16 (char *dst, int nfrm);
char *play_float (const float *src, char *dst, int nfrm, int step);
char *play_32 (const float *src, char *dst, int nfrm, int step);
char *play_24 (const float *src, char *dst, int nfrm, int step);
char *play_16 (const float *src, char *dst, int nfrm, int step);
char *play_32swap (const float *src, char *dst, int nfrm, int step);
char *play_24swap (const float *src, char *dst, int nfrm, int step);
char *play_16swap (const float *src, char *dst, int nfrm, int step);
const char *capt_float (const char *src, float *dst, int nfrm, int step);
const char *capt_32 (const char *src, float *dst, int nfrm, int step);
const char *capt_24 (const char *src, float *dst, int nfrm, int step);
const char *capt_16 (const char *src, float *dst, int nfrm, int step);
const char *capt_32swap (const char *src, float *dst, int nfrm, int step);
const char *capt_24swap (const char *src, float *dst, int nfrm, int step);
const char *capt_16swap (const char *src, float *dst, int nfrm, int step);
unsigned int _fsamp;
snd_pcm_uframes_t _fsize;
unsigned int _play_nfrag;
unsigned int _real_nfrag;
unsigned int _capt_nfrag;
unsigned int _debug;
int _state;
snd_pcm_t *_play_handle;
snd_pcm_t *_capt_handle;
snd_ctl_t *_ctrl_handle;
snd_pcm_hw_params_t *_play_hwpar;
snd_pcm_sw_params_t *_play_swpar;
snd_pcm_hw_params_t *_capt_hwpar;
snd_pcm_sw_params_t *_capt_swpar;
snd_pcm_format_t _play_format;
snd_pcm_format_t _capt_format;
snd_pcm_access_t _play_access;
snd_pcm_access_t _capt_access;
unsigned int _play_nchan;
unsigned int _capt_nchan;
float _play_xrun;
float _capt_xrun;
bool _synced;
int _play_npfd;
int _capt_npfd;
struct pollfd _poll_fd [MAXPFD];
snd_pcm_uframes_t _capt_offs;
snd_pcm_uframes_t _play_offs;
int _play_step;
int _capt_step;
char *_play_ptr [MAXCHAN];
const char *_capt_ptr [MAXCHAN];
clear_function _clear_func;
play_function _play_func;
capt_function _capt_func;
void *_dummy [16];
};
#endif