alsa-utils/alsaloop/alsaloop.h

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/*
* A simple PCM loopback utility
* Copyright (c) 2010 by Jaroslav Kysela <perex@perex.cz>
*
* 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 2 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, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include "aconfig.h"
#ifdef HAVE_SAMPLERATE_H
#define USE_SAMPLERATE
#include <samplerate.h>
#else
enum {
SRC_SINC_BEST_QUALITY = 0,
SRC_SINC_MEDIUM_QUALITY = 1,
SRC_SINC_FASTEST = 2,
SRC_ZERO_ORDER_HOLD = 3,
SRC_LINEAR = 4
};
#endif
#define MAX_ARGS 128
#define MAX_MIXERS 64
#if 0
#define FILE_PWRITE "/tmp/alsaloop.praw"
#define FILE_CWRITE "/tmp/alsaloop.craw"
#endif
#define WORKAROUND_SERIALOPEN (1<<0)
typedef enum _sync_type {
SYNC_TYPE_NONE = 0,
SYNC_TYPE_SIMPLE, /* add or remove samples */
SYNC_TYPE_CAPTRATESHIFT,
SYNC_TYPE_PLAYRATESHIFT,
SYNC_TYPE_SAMPLERATE,
SYNC_TYPE_AUTO, /* order: CAPTRATESHIFT, PLAYRATESHIFT, */
/* SAMPLERATE, SIMPLE */
SYNC_TYPE_LAST = SYNC_TYPE_AUTO
} sync_type_t;
typedef enum _slave_type {
SLAVE_TYPE_AUTO = 0,
SLAVE_TYPE_ON = 1,
SLAVE_TYPE_OFF = 2,
SLAVE_TYPE_LAST = SLAVE_TYPE_OFF
} slave_type_t;
struct loopback_control {
snd_ctl_elem_id_t *id;
snd_ctl_elem_info_t *info;
snd_ctl_elem_value_t *value;
};
struct loopback_mixer {
unsigned int skip:1;
struct loopback_control src;
struct loopback_control dst;
struct loopback_mixer *next;
};
struct loopback_ossmixer {
unsigned int skip:1;
const char *alsa_id;
int alsa_index;
const char *oss_id;
struct loopback_ossmixer *next;
};
struct loopback_handle {
struct loopback *loopback;
char *device;
char *ctldev;
char *id;
int card_number;
snd_pcm_t *handle;
snd_pcm_access_t access;
snd_pcm_format_t format;
unsigned int rate;
unsigned int rate_req;
unsigned int channels;
unsigned int buffer_size;
unsigned int period_size;
unsigned int buffer_size_req;
unsigned int period_size_req;
unsigned int frame_size;
unsigned int resample:1; /* do resample */
unsigned int nblock:1; /* do block (period size) transfers */
unsigned int xrun_pending:1;
unsigned int pollfd_count;
/* I/O job */
char *buf; /* I/O buffer */
snd_pcm_uframes_t buf_pos; /* I/O position */
snd_pcm_uframes_t buf_count; /* filled samples */
snd_pcm_uframes_t buf_size; /* buffer size in frames */
snd_pcm_uframes_t buf_over; /* capture buffer overflow */
/* statistics */
snd_pcm_uframes_t max;
unsigned long long counter;
unsigned long sync_point; /* in samples */
snd_pcm_sframes_t last_delay;
double pitch;
snd_pcm_uframes_t total_queued;
/* control */
snd_ctl_t *ctl;
unsigned int ctl_pollfd_count;
snd_ctl_elem_value_t *ctl_notify;
snd_ctl_elem_value_t *ctl_rate_shift;
snd_ctl_elem_value_t *ctl_active;
snd_ctl_elem_value_t *ctl_format;
snd_ctl_elem_value_t *ctl_rate;
snd_ctl_elem_value_t *ctl_channels;
};
struct loopback {
char *id;
struct loopback_handle *capt;
struct loopback_handle *play;
snd_pcm_uframes_t latency; /* final latency */
unsigned int latency_req; /* in frames / 2 */
unsigned int latency_reqtime; /* in us / 2 */
unsigned long loop_time; /* ~0 = unlimited (in seconds) */
unsigned long long loop_limit; /* ~0 = unlimited (in frames) */
snd_output_t *output;
int pollfd_count;
int active_pollfd_count;
unsigned int linked:1; /* linked streams */
unsigned int reinit:1;
unsigned int running:1;
sync_type_t sync; /* type of sync */
slave_type_t slave;
int thread; /* thread number */
/* statistics */
double pitch;
double pitch_delta;
snd_pcm_sframes_t pitch_diff;
snd_pcm_sframes_t pitch_diff_min;
snd_pcm_sframes_t pitch_diff_max;
unsigned int total_queued_count;
snd_timestamp_t tstamp_start;
snd_timestamp_t tstamp_end;
/* control mixer */
struct loopback_mixer *controls;
struct loopback_ossmixer *oss_controls;
/* sample rate */
unsigned int use_samplerate:1;
#ifdef USE_SAMPLERATE
unsigned int src_enable:1;
int src_converter_type;
SRC_STATE *src_state;
SRC_DATA src_data;
unsigned int src_out_frames;
#endif
#ifdef FILE_CWRITE
FILE *cfile;
#endif
#ifdef FILE_PWRITE
FILE *pfile;
#endif
};
extern int verbose;
extern int workarounds;
extern int use_syslog;
#define logit(priority, fmt, args...) do { \
if (use_syslog) \
syslog(priority, fmt, ##args); \
else \
fprintf(stderr, fmt, ##args); \
} while (0)
int pcmjob_init(struct loopback *loop);
int pcmjob_done(struct loopback *loop);
int pcmjob_start(struct loopback *loop);
int pcmjob_stop(struct loopback *loop);
int pcmjob_pollfds_init(struct loopback *loop, struct pollfd *fds);
int pcmjob_pollfds_handle(struct loopback *loop, struct pollfd *fds);
int control_parse_id(const char *str, snd_ctl_elem_id_t *id);
int control_id_match(snd_ctl_elem_id_t *id1, snd_ctl_elem_id_t *id2);
int control_init(struct loopback *loop);
int control_done(struct loopback *loop);
int control_event(struct loopback_handle *lhandle, snd_ctl_event_t *ev);