/home/alsa/tmp/cvs/alsa-lib/include/pcm.h

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/*
 *   This library is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU Lesser General Public License as
 *   published by the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
 *
 *   You should have received a copy of the GNU Lesser General Public
 *   License along with this library; if not, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 *
 */

#ifndef __ALSA_PCM_H
#define __ALSA_PCM_H

#ifdef __cplusplus
extern "C" {
#endif

#define SND_PCM_DLSYM_VERSION           _dlsym_pcm_001

typedef struct _snd_pcm_info snd_pcm_info_t;

typedef struct _snd_pcm_hw_params snd_pcm_hw_params_t;

typedef struct _snd_pcm_sw_params snd_pcm_sw_params_t;
 typedef struct _snd_pcm_status snd_pcm_status_t;
typedef struct _snd_pcm_access_mask snd_pcm_access_mask_t;
typedef struct _snd_pcm_format_mask snd_pcm_format_mask_t;
typedef struct _snd_pcm_subformat_mask snd_pcm_subformat_mask_t;

typedef enum _snd_pcm_class {
        SND_PCM_CLASS_GENERIC = 0,
        SND_PCM_CLASS_MULTI,
        SND_PCM_CLASS_MODEM,
        SND_PCM_CLASS_DIGITIZER,
        SND_PCM_CLASS_LAST = SND_PCM_CLASS_DIGITIZER
} snd_pcm_class_t;

typedef enum _snd_pcm_subclass {
        SND_PCM_SUBCLASS_GENERIC_MIX = 0,
        SND_PCM_SUBCLASS_MULTI_MIX,
        SND_PCM_SUBCLASS_LAST = SND_PCM_SUBCLASS_MULTI_MIX
} snd_pcm_subclass_t;

typedef enum _snd_pcm_stream {
        SND_PCM_STREAM_PLAYBACK = 0,
        SND_PCM_STREAM_CAPTURE,
        SND_PCM_STREAM_LAST = SND_PCM_STREAM_CAPTURE
} snd_pcm_stream_t;

typedef enum _snd_pcm_access {
        SND_PCM_ACCESS_MMAP_INTERLEAVED = 0,
        SND_PCM_ACCESS_MMAP_NONINTERLEAVED,
        SND_PCM_ACCESS_MMAP_COMPLEX,
        SND_PCM_ACCESS_RW_INTERLEAVED,
        SND_PCM_ACCESS_RW_NONINTERLEAVED,
        SND_PCM_ACCESS_LAST = SND_PCM_ACCESS_RW_NONINTERLEAVED
} snd_pcm_access_t;

typedef enum _snd_pcm_format {
        SND_PCM_FORMAT_UNKNOWN = -1,
        SND_PCM_FORMAT_S8 = 0,
        SND_PCM_FORMAT_U8,
        SND_PCM_FORMAT_S16_LE,
        SND_PCM_FORMAT_S16_BE,
        SND_PCM_FORMAT_U16_LE,
        SND_PCM_FORMAT_U16_BE,
        SND_PCM_FORMAT_S24_LE,
        SND_PCM_FORMAT_S24_BE,
        SND_PCM_FORMAT_U24_LE,
        SND_PCM_FORMAT_U24_BE,
        SND_PCM_FORMAT_S32_LE,
        SND_PCM_FORMAT_S32_BE,
        SND_PCM_FORMAT_U32_LE,
        SND_PCM_FORMAT_U32_BE,
        SND_PCM_FORMAT_FLOAT_LE,
        SND_PCM_FORMAT_FLOAT_BE,
        SND_PCM_FORMAT_FLOAT64_LE,
        SND_PCM_FORMAT_FLOAT64_BE,
        SND_PCM_FORMAT_IEC958_SUBFRAME_LE,
        SND_PCM_FORMAT_IEC958_SUBFRAME_BE,
        SND_PCM_FORMAT_MU_LAW,
        SND_PCM_FORMAT_A_LAW,
        SND_PCM_FORMAT_IMA_ADPCM,
        SND_PCM_FORMAT_MPEG,
        SND_PCM_FORMAT_GSM,
        SND_PCM_FORMAT_SPECIAL = 31,
        SND_PCM_FORMAT_S24_3LE = 32,
        SND_PCM_FORMAT_S24_3BE,
        SND_PCM_FORMAT_U24_3LE,
        SND_PCM_FORMAT_U24_3BE,
        SND_PCM_FORMAT_S20_3LE,
        SND_PCM_FORMAT_S20_3BE,
        SND_PCM_FORMAT_U20_3LE,
        SND_PCM_FORMAT_U20_3BE,
        SND_PCM_FORMAT_S18_3LE,
        SND_PCM_FORMAT_S18_3BE,
        SND_PCM_FORMAT_U18_3LE,
        SND_PCM_FORMAT_U18_3BE,
        SND_PCM_FORMAT_LAST = SND_PCM_FORMAT_U18_3BE,

#if __BYTE_ORDER == __LITTLE_ENDIAN

        SND_PCM_FORMAT_S16 = SND_PCM_FORMAT_S16_LE,
        SND_PCM_FORMAT_U16 = SND_PCM_FORMAT_U16_LE,
        SND_PCM_FORMAT_S24 = SND_PCM_FORMAT_S24_LE,
        SND_PCM_FORMAT_U24 = SND_PCM_FORMAT_U24_LE,
        SND_PCM_FORMAT_S32 = SND_PCM_FORMAT_S32_LE,
        SND_PCM_FORMAT_U32 = SND_PCM_FORMAT_U32_LE,
        SND_PCM_FORMAT_FLOAT = SND_PCM_FORMAT_FLOAT_LE,
        SND_PCM_FORMAT_FLOAT64 = SND_PCM_FORMAT_FLOAT64_LE,
        SND_PCM_FORMAT_IEC958_SUBFRAME = SND_PCM_FORMAT_IEC958_SUBFRAME_LE
#elif __BYTE_ORDER == __BIG_ENDIAN

        SND_PCM_FORMAT_S16 = SND_PCM_FORMAT_S16_BE,
        SND_PCM_FORMAT_U16 = SND_PCM_FORMAT_U16_BE,
        SND_PCM_FORMAT_S24 = SND_PCM_FORMAT_S24_BE,
        SND_PCM_FORMAT_U24 = SND_PCM_FORMAT_U24_BE,
        SND_PCM_FORMAT_S32 = SND_PCM_FORMAT_S32_BE,
        SND_PCM_FORMAT_U32 = SND_PCM_FORMAT_U32_BE,
        SND_PCM_FORMAT_FLOAT = SND_PCM_FORMAT_FLOAT_BE,
        SND_PCM_FORMAT_FLOAT64 = SND_PCM_FORMAT_FLOAT64_BE,
        SND_PCM_FORMAT_IEC958_SUBFRAME = SND_PCM_FORMAT_IEC958_SUBFRAME_BE
#else
#error "Unknown endian"
#endif
} snd_pcm_format_t;

typedef enum _snd_pcm_subformat {
        SND_PCM_SUBFORMAT_STD = 0,
        SND_PCM_SUBFORMAT_LAST = SND_PCM_SUBFORMAT_STD
} snd_pcm_subformat_t;

typedef enum _snd_pcm_state {
        SND_PCM_STATE_OPEN = 0,
        SND_PCM_STATE_SETUP,
        SND_PCM_STATE_PREPARED,
        SND_PCM_STATE_RUNNING,
        SND_PCM_STATE_XRUN,
        SND_PCM_STATE_DRAINING,
        SND_PCM_STATE_PAUSED,
        SND_PCM_STATE_SUSPENDED,
        SND_PCM_STATE_DISCONNECTED,
        SND_PCM_STATE_LAST = SND_PCM_STATE_DISCONNECTED
} snd_pcm_state_t;

typedef enum _snd_pcm_start {
        SND_PCM_START_DATA = 0,
        SND_PCM_START_EXPLICIT,
        SND_PCM_START_LAST = SND_PCM_START_EXPLICIT
} snd_pcm_start_t;

typedef enum _snd_pcm_xrun {
        SND_PCM_XRUN_NONE = 0,
        SND_PCM_XRUN_STOP,
        SND_PCM_XRUN_LAST = SND_PCM_XRUN_STOP
} snd_pcm_xrun_t;

typedef enum _snd_pcm_tstamp {
        SND_PCM_TSTAMP_NONE = 0,
        SND_PCM_TSTAMP_ENABLE,
        SND_PCM_TSTAMP_MMAP = SND_PCM_TSTAMP_ENABLE,
        SND_PCM_TSTAMP_LAST = SND_PCM_TSTAMP_ENABLE
} snd_pcm_tstamp_t;

typedef unsigned long snd_pcm_uframes_t;
typedef long snd_pcm_sframes_t;

#define SND_PCM_NONBLOCK                0x00000001

#define SND_PCM_ASYNC                   0x00000002

#define SND_PCM_NO_AUTO_RESAMPLE        0x00010000

#define SND_PCM_NO_AUTO_CHANNELS        0x00020000

#define SND_PCM_NO_AUTO_FORMAT          0x00040000

#define SND_PCM_NO_SOFTVOL              0x00080000

typedef struct _snd_pcm snd_pcm_t;

enum _snd_pcm_type {
        SND_PCM_TYPE_HW = 0,
        SND_PCM_TYPE_HOOKS,
        SND_PCM_TYPE_MULTI,
        SND_PCM_TYPE_FILE,
        SND_PCM_TYPE_NULL,
        SND_PCM_TYPE_SHM,
        SND_PCM_TYPE_INET,
        SND_PCM_TYPE_COPY,
        SND_PCM_TYPE_LINEAR,
        SND_PCM_TYPE_ALAW,
        SND_PCM_TYPE_MULAW,
        SND_PCM_TYPE_ADPCM,
        SND_PCM_TYPE_RATE,
        SND_PCM_TYPE_ROUTE,
        SND_PCM_TYPE_PLUG,
        SND_PCM_TYPE_SHARE,
        SND_PCM_TYPE_METER,
        SND_PCM_TYPE_MIX,
        SND_PCM_TYPE_DROUTE,
        SND_PCM_TYPE_LBSERVER,
        SND_PCM_TYPE_LINEAR_FLOAT,
        SND_PCM_TYPE_LADSPA,
        SND_PCM_TYPE_DMIX,
        SND_PCM_TYPE_JACK,
        SND_PCM_TYPE_DSNOOP,
        SND_PCM_TYPE_DSHARE,
        SND_PCM_TYPE_IEC958,
        SND_PCM_TYPE_SOFTVOL,
        SND_PCM_TYPE_IOPLUG,
        SND_PCM_TYPE_EXTPLUG,
        SND_PCM_TYPE_MMAP_EMUL,
        SND_PCM_TYPE_LAST = SND_PCM_TYPE_MMAP_EMUL
};

typedef enum _snd_pcm_type snd_pcm_type_t;

typedef struct _snd_pcm_channel_area {
        void *addr;
        unsigned int first;
        unsigned int step;
} snd_pcm_channel_area_t;

typedef union _snd_pcm_sync_id {
        unsigned char id[16];
        unsigned short id16[8];
        unsigned int id32[4];
} snd_pcm_sync_id_t;

typedef struct _snd_pcm_scope snd_pcm_scope_t;

int snd_pcm_open(snd_pcm_t **pcm, const char *name, 
                 snd_pcm_stream_t stream, int mode);
int snd_pcm_open_lconf(snd_pcm_t **pcm, const char *name, 
                       snd_pcm_stream_t stream, int mode,
                       snd_config_t *lconf);
int snd_pcm_open_fallback(snd_pcm_t **pcm, snd_config_t *root,
                          const char *name, const char *orig_name,
                          snd_pcm_stream_t stream, int mode);

int snd_pcm_close(snd_pcm_t *pcm);
const char *snd_pcm_name(snd_pcm_t *pcm);
snd_pcm_type_t snd_pcm_type(snd_pcm_t *pcm);
snd_pcm_stream_t snd_pcm_stream(snd_pcm_t *pcm);
int snd_pcm_poll_descriptors_count(snd_pcm_t *pcm);
int snd_pcm_poll_descriptors(snd_pcm_t *pcm, struct pollfd *pfds, unsigned int space);
int snd_pcm_poll_descriptors_revents(snd_pcm_t *pcm, struct pollfd *pfds, unsigned int nfds, unsigned short *revents);
int snd_pcm_nonblock(snd_pcm_t *pcm, int nonblock);
int snd_async_add_pcm_handler(snd_async_handler_t **handler, snd_pcm_t *pcm, 
                              snd_async_callback_t callback, void *private_data);
snd_pcm_t *snd_async_handler_get_pcm(snd_async_handler_t *handler);
int snd_pcm_info(snd_pcm_t *pcm, snd_pcm_info_t *info);
int snd_pcm_hw_params_current(snd_pcm_t *pcm, snd_pcm_hw_params_t *params);
int snd_pcm_hw_params(snd_pcm_t *pcm, snd_pcm_hw_params_t *params);
int snd_pcm_hw_free(snd_pcm_t *pcm);
int snd_pcm_sw_params_current(snd_pcm_t *pcm, snd_pcm_sw_params_t *params);
int snd_pcm_sw_params(snd_pcm_t *pcm, snd_pcm_sw_params_t *params);
int snd_pcm_prepare(snd_pcm_t *pcm);
int snd_pcm_reset(snd_pcm_t *pcm);
int snd_pcm_status(snd_pcm_t *pcm, snd_pcm_status_t *status);
int snd_pcm_start(snd_pcm_t *pcm);
int snd_pcm_drop(snd_pcm_t *pcm);
int snd_pcm_drain(snd_pcm_t *pcm);
int snd_pcm_pause(snd_pcm_t *pcm, int enable);
snd_pcm_state_t snd_pcm_state(snd_pcm_t *pcm);
int snd_pcm_hwsync(snd_pcm_t *pcm);
int snd_pcm_delay(snd_pcm_t *pcm, snd_pcm_sframes_t *delayp);
int snd_pcm_resume(snd_pcm_t *pcm);
int snd_pcm_htimestamp(snd_pcm_t *pcm, snd_pcm_uframes_t *avail, snd_htimestamp_t *tstamp);
snd_pcm_sframes_t snd_pcm_avail(snd_pcm_t *pcm);
snd_pcm_sframes_t snd_pcm_avail_update(snd_pcm_t *pcm);
int snd_pcm_avail_delay(snd_pcm_t *pcm, snd_pcm_sframes_t *availp, snd_pcm_sframes_t *delayp);
snd_pcm_sframes_t snd_pcm_rewindable(snd_pcm_t *pcm);
snd_pcm_sframes_t snd_pcm_rewind(snd_pcm_t *pcm, snd_pcm_uframes_t frames);
snd_pcm_sframes_t snd_pcm_forwardable(snd_pcm_t *pcm);
snd_pcm_sframes_t snd_pcm_forward(snd_pcm_t *pcm, snd_pcm_uframes_t frames);
snd_pcm_sframes_t snd_pcm_writei(snd_pcm_t *pcm, const void *buffer, snd_pcm_uframes_t size);
snd_pcm_sframes_t snd_pcm_readi(snd_pcm_t *pcm, void *buffer, snd_pcm_uframes_t size);
snd_pcm_sframes_t snd_pcm_writen(snd_pcm_t *pcm, void **bufs, snd_pcm_uframes_t size);
snd_pcm_sframes_t snd_pcm_readn(snd_pcm_t *pcm, void **bufs, snd_pcm_uframes_t size);
int snd_pcm_wait(snd_pcm_t *pcm, int timeout);

int snd_pcm_link(snd_pcm_t *pcm1, snd_pcm_t *pcm2);
int snd_pcm_unlink(snd_pcm_t *pcm);

//int snd_pcm_mixer_element(snd_pcm_t *pcm, snd_mixer_t *mixer, snd_mixer_elem_t **elem);

/*
 * application helpers - these functions are implemented on top
 * of the basic API
 */

int snd_pcm_recover(snd_pcm_t *pcm, int err, int silent);
int snd_pcm_set_params(snd_pcm_t *pcm,
                       snd_pcm_format_t format,
                       snd_pcm_access_t access,
                       unsigned int channels,
                       unsigned int rate,
                       int soft_resample,
                       unsigned int latency);
int snd_pcm_get_params(snd_pcm_t *pcm,
                       snd_pcm_uframes_t *buffer_size,
                       snd_pcm_uframes_t *period_size);

size_t snd_pcm_info_sizeof(void);
#define snd_pcm_info_alloca(ptr) __snd_alloca(ptr, snd_pcm_info)
int snd_pcm_info_malloc(snd_pcm_info_t **ptr);
void snd_pcm_info_free(snd_pcm_info_t *obj);
void snd_pcm_info_copy(snd_pcm_info_t *dst, const snd_pcm_info_t *src);
unsigned int snd_pcm_info_get_device(const snd_pcm_info_t *obj);
unsigned int snd_pcm_info_get_subdevice(const snd_pcm_info_t *obj);
snd_pcm_stream_t snd_pcm_info_get_stream(const snd_pcm_info_t *obj);
int snd_pcm_info_get_card(const snd_pcm_info_t *obj);
const char *snd_pcm_info_get_id(const snd_pcm_info_t *obj);
const char *snd_pcm_info_get_name(const snd_pcm_info_t *obj);
const char *snd_pcm_info_get_subdevice_name(const snd_pcm_info_t *obj);
snd_pcm_class_t snd_pcm_info_get_class(const snd_pcm_info_t *obj);
snd_pcm_subclass_t snd_pcm_info_get_subclass(const snd_pcm_info_t *obj);
unsigned int snd_pcm_info_get_subdevices_count(const snd_pcm_info_t *obj);
unsigned int snd_pcm_info_get_subdevices_avail(const snd_pcm_info_t *obj);
snd_pcm_sync_id_t snd_pcm_info_get_sync(const snd_pcm_info_t *obj);
void snd_pcm_info_set_device(snd_pcm_info_t *obj, unsigned int val);
void snd_pcm_info_set_subdevice(snd_pcm_info_t *obj, unsigned int val);
void snd_pcm_info_set_stream(snd_pcm_info_t *obj, snd_pcm_stream_t val);

int snd_pcm_hw_params_any(snd_pcm_t *pcm, snd_pcm_hw_params_t *params);

int snd_pcm_hw_params_can_mmap_sample_resolution(const snd_pcm_hw_params_t *params);
int snd_pcm_hw_params_is_double(const snd_pcm_hw_params_t *params);
int snd_pcm_hw_params_is_batch(const snd_pcm_hw_params_t *params);
int snd_pcm_hw_params_is_block_transfer(const snd_pcm_hw_params_t *params);
int snd_pcm_hw_params_is_monotonic(const snd_pcm_hw_params_t *params);
int snd_pcm_hw_params_can_overrange(const snd_pcm_hw_params_t *params);
int snd_pcm_hw_params_can_pause(const snd_pcm_hw_params_t *params);
int snd_pcm_hw_params_can_resume(const snd_pcm_hw_params_t *params);
int snd_pcm_hw_params_is_half_duplex(const snd_pcm_hw_params_t *params);
int snd_pcm_hw_params_is_joint_duplex(const snd_pcm_hw_params_t *params);
int snd_pcm_hw_params_can_sync_start(const snd_pcm_hw_params_t *params);
int snd_pcm_hw_params_can_disable_period_wakeup(const snd_pcm_hw_params_t *params);
int snd_pcm_hw_params_get_rate_numden(const snd_pcm_hw_params_t *params,
                                      unsigned int *rate_num,
                                      unsigned int *rate_den);
int snd_pcm_hw_params_get_sbits(const snd_pcm_hw_params_t *params);
int snd_pcm_hw_params_get_fifo_size(const snd_pcm_hw_params_t *params);

#if 0
typedef struct _snd_pcm_hw_strategy snd_pcm_hw_strategy_t;

/* choices need to be sorted on ascending badness */
typedef struct _snd_pcm_hw_strategy_simple_choices_list {
        unsigned int value;
        unsigned int badness;
} snd_pcm_hw_strategy_simple_choices_list_t;

int snd_pcm_hw_params_strategy(snd_pcm_t *pcm, snd_pcm_hw_params_t *params,
                               const snd_pcm_hw_strategy_t *strategy,
                               unsigned int badness_min,
                               unsigned int badness_max);

void snd_pcm_hw_strategy_free(snd_pcm_hw_strategy_t *strategy);
int snd_pcm_hw_strategy_simple(snd_pcm_hw_strategy_t **strategyp,
                               unsigned int badness_min,
                               unsigned int badness_max);
int snd_pcm_hw_params_try_explain_failure(snd_pcm_t *pcm,
                                          snd_pcm_hw_params_t *fail,
                                          snd_pcm_hw_params_t *success,
                                          unsigned int depth,
                                          snd_output_t *out);

#endif

size_t snd_pcm_hw_params_sizeof(void);
#define snd_pcm_hw_params_alloca(ptr) __snd_alloca(ptr, snd_pcm_hw_params)
int snd_pcm_hw_params_malloc(snd_pcm_hw_params_t **ptr);
void snd_pcm_hw_params_free(snd_pcm_hw_params_t *obj);
void snd_pcm_hw_params_copy(snd_pcm_hw_params_t *dst, const snd_pcm_hw_params_t *src);

#if !defined(ALSA_LIBRARY_BUILD) && !defined(ALSA_PCM_OLD_HW_PARAMS_API)

int snd_pcm_hw_params_get_access(const snd_pcm_hw_params_t *params, snd_pcm_access_t *_access);
int snd_pcm_hw_params_test_access(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_access_t _access);
int snd_pcm_hw_params_set_access(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_access_t _access);
int snd_pcm_hw_params_set_access_first(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_access_t *_access);
int snd_pcm_hw_params_set_access_last(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_access_t *_access);
int snd_pcm_hw_params_set_access_mask(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_access_mask_t *mask);
int snd_pcm_hw_params_get_access_mask(snd_pcm_hw_params_t *params, snd_pcm_access_mask_t *mask);

int snd_pcm_hw_params_get_format(const snd_pcm_hw_params_t *params, snd_pcm_format_t *val);
int snd_pcm_hw_params_test_format(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_format_t val);
int snd_pcm_hw_params_set_format(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_format_t val);
int snd_pcm_hw_params_set_format_first(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_format_t *format);
int snd_pcm_hw_params_set_format_last(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_format_t *format);
int snd_pcm_hw_params_set_format_mask(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_format_mask_t *mask);
void snd_pcm_hw_params_get_format_mask(snd_pcm_hw_params_t *params, snd_pcm_format_mask_t *mask);

int snd_pcm_hw_params_get_subformat(const snd_pcm_hw_params_t *params, snd_pcm_subformat_t *subformat);
int snd_pcm_hw_params_test_subformat(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_subformat_t subformat);
int snd_pcm_hw_params_set_subformat(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_subformat_t subformat);
int snd_pcm_hw_params_set_subformat_first(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_subformat_t *subformat);
int snd_pcm_hw_params_set_subformat_last(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_subformat_t *subformat);
int snd_pcm_hw_params_set_subformat_mask(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_subformat_mask_t *mask);
void snd_pcm_hw_params_get_subformat_mask(snd_pcm_hw_params_t *params, snd_pcm_subformat_mask_t *mask);

int snd_pcm_hw_params_get_channels(const snd_pcm_hw_params_t *params, unsigned int *val);
int snd_pcm_hw_params_get_channels_min(const snd_pcm_hw_params_t *params, unsigned int *val);
int snd_pcm_hw_params_get_channels_max(const snd_pcm_hw_params_t *params, unsigned int *val);
int snd_pcm_hw_params_test_channels(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int val);
int snd_pcm_hw_params_set_channels(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int val);
int snd_pcm_hw_params_set_channels_min(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val);
int snd_pcm_hw_params_set_channels_max(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val);
int snd_pcm_hw_params_set_channels_minmax(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *min, unsigned int *max);
int snd_pcm_hw_params_set_channels_near(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val);
int snd_pcm_hw_params_set_channels_first(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val);
int snd_pcm_hw_params_set_channels_last(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val);

int snd_pcm_hw_params_get_rate(const snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_get_rate_min(const snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_get_rate_max(const snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_test_rate(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int val, int dir);
int snd_pcm_hw_params_set_rate(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int val, int dir);
int snd_pcm_hw_params_set_rate_min(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_set_rate_max(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_set_rate_minmax(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *min, int *mindir, unsigned int *max, int *maxdir);
int snd_pcm_hw_params_set_rate_near(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_set_rate_first(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_set_rate_last(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_set_rate_resample(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int val);
int snd_pcm_hw_params_get_rate_resample(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val);
int snd_pcm_hw_params_set_export_buffer(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int val);
int snd_pcm_hw_params_get_export_buffer(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val);
int snd_pcm_hw_params_set_period_wakeup(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int val);
int snd_pcm_hw_params_get_period_wakeup(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val);

int snd_pcm_hw_params_get_period_time(const snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_get_period_time_min(const snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_get_period_time_max(const snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_test_period_time(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int val, int dir);
int snd_pcm_hw_params_set_period_time(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int val, int dir);
int snd_pcm_hw_params_set_period_time_min(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_set_period_time_max(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_set_period_time_minmax(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *min, int *mindir, unsigned int *max, int *maxdir);
int snd_pcm_hw_params_set_period_time_near(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_set_period_time_first(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_set_period_time_last(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir);

int snd_pcm_hw_params_get_period_size(const snd_pcm_hw_params_t *params, snd_pcm_uframes_t *frames, int *dir);
int snd_pcm_hw_params_get_period_size_min(const snd_pcm_hw_params_t *params, snd_pcm_uframes_t *frames, int *dir);
int snd_pcm_hw_params_get_period_size_max(const snd_pcm_hw_params_t *params, snd_pcm_uframes_t *frames, int *dir);
int snd_pcm_hw_params_test_period_size(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_uframes_t val, int dir);
int snd_pcm_hw_params_set_period_size(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_uframes_t val, int dir);
int snd_pcm_hw_params_set_period_size_min(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_uframes_t *val, int *dir);
int snd_pcm_hw_params_set_period_size_max(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_uframes_t *val, int *dir);
int snd_pcm_hw_params_set_period_size_minmax(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_uframes_t *min, int *mindir, snd_pcm_uframes_t *max, int *maxdir);
int snd_pcm_hw_params_set_period_size_near(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_uframes_t *val, int *dir);
int snd_pcm_hw_params_set_period_size_first(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_uframes_t *val, int *dir);
int snd_pcm_hw_params_set_period_size_last(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_uframes_t *val, int *dir);
int snd_pcm_hw_params_set_period_size_integer(snd_pcm_t *pcm, snd_pcm_hw_params_t *params);

int snd_pcm_hw_params_get_periods(const snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_get_periods_min(const snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_get_periods_max(const snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_test_periods(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int val, int dir);
int snd_pcm_hw_params_set_periods(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int val, int dir);
int snd_pcm_hw_params_set_periods_min(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_set_periods_max(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_set_periods_minmax(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *min, int *mindir, unsigned int *max, int *maxdir);
int snd_pcm_hw_params_set_periods_near(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_set_periods_first(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_set_periods_last(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_set_periods_integer(snd_pcm_t *pcm, snd_pcm_hw_params_t *params);

int snd_pcm_hw_params_get_buffer_time(const snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_get_buffer_time_min(const snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_get_buffer_time_max(const snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_test_buffer_time(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int val, int dir);
int snd_pcm_hw_params_set_buffer_time(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int val, int dir);
int snd_pcm_hw_params_set_buffer_time_min(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_set_buffer_time_max(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_set_buffer_time_minmax(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *min, int *mindir, unsigned int *max, int *maxdir);
int snd_pcm_hw_params_set_buffer_time_near(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_set_buffer_time_first(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir);
int snd_pcm_hw_params_set_buffer_time_last(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir);

int snd_pcm_hw_params_get_buffer_size(const snd_pcm_hw_params_t *params, snd_pcm_uframes_t *val);
int snd_pcm_hw_params_get_buffer_size_min(const snd_pcm_hw_params_t *params, snd_pcm_uframes_t *val);
int snd_pcm_hw_params_get_buffer_size_max(const snd_pcm_hw_params_t *params, snd_pcm_uframes_t *val);
int snd_pcm_hw_params_test_buffer_size(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_uframes_t val);
int snd_pcm_hw_params_set_buffer_size(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_uframes_t val);
int snd_pcm_hw_params_set_buffer_size_min(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_uframes_t *val);
int snd_pcm_hw_params_set_buffer_size_max(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_uframes_t *val);
int snd_pcm_hw_params_set_buffer_size_minmax(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_uframes_t *min, snd_pcm_uframes_t *max);
int snd_pcm_hw_params_set_buffer_size_near(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_uframes_t *val);
int snd_pcm_hw_params_set_buffer_size_first(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_uframes_t *val);
int snd_pcm_hw_params_set_buffer_size_last(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_uframes_t *val);

#endif /* !ALSA_LIBRARY_BUILD && !ALSA_PCM_OLD_HW_PARAMS_API */

int snd_pcm_hw_params_get_min_align(const snd_pcm_hw_params_t *params, snd_pcm_uframes_t *val);

size_t snd_pcm_sw_params_sizeof(void);
#define snd_pcm_sw_params_alloca(ptr) __snd_alloca(ptr, snd_pcm_sw_params)
int snd_pcm_sw_params_malloc(snd_pcm_sw_params_t **ptr);
void snd_pcm_sw_params_free(snd_pcm_sw_params_t *obj);
void snd_pcm_sw_params_copy(snd_pcm_sw_params_t *dst, const snd_pcm_sw_params_t *src);
int snd_pcm_sw_params_get_boundary(const snd_pcm_sw_params_t *params, snd_pcm_uframes_t *val);

#if !defined(ALSA_LIBRARY_BUILD) && !defined(ALSA_PCM_OLD_SW_PARAMS_API)

int snd_pcm_sw_params_set_tstamp_mode(snd_pcm_t *pcm, snd_pcm_sw_params_t *params, snd_pcm_tstamp_t val);
int snd_pcm_sw_params_get_tstamp_mode(const snd_pcm_sw_params_t *params, snd_pcm_tstamp_t *val);
int snd_pcm_sw_params_set_avail_min(snd_pcm_t *pcm, snd_pcm_sw_params_t *params, snd_pcm_uframes_t val);
int snd_pcm_sw_params_get_avail_min(const snd_pcm_sw_params_t *params, snd_pcm_uframes_t *val);
int snd_pcm_sw_params_set_period_event(snd_pcm_t *pcm, snd_pcm_sw_params_t *params, int val);
int snd_pcm_sw_params_get_period_event(const snd_pcm_sw_params_t *params, int *val);
int snd_pcm_sw_params_set_start_threshold(snd_pcm_t *pcm, snd_pcm_sw_params_t *params, snd_pcm_uframes_t val);
int snd_pcm_sw_params_get_start_threshold(const snd_pcm_sw_params_t *paramsm, snd_pcm_uframes_t *val);
int snd_pcm_sw_params_set_stop_threshold(snd_pcm_t *pcm, snd_pcm_sw_params_t *params, snd_pcm_uframes_t val);
int snd_pcm_sw_params_get_stop_threshold(const snd_pcm_sw_params_t *params, snd_pcm_uframes_t *val);
int snd_pcm_sw_params_set_silence_threshold(snd_pcm_t *pcm, snd_pcm_sw_params_t *params, snd_pcm_uframes_t val);
int snd_pcm_sw_params_get_silence_threshold(const snd_pcm_sw_params_t *params, snd_pcm_uframes_t *val);
int snd_pcm_sw_params_set_silence_size(snd_pcm_t *pcm, snd_pcm_sw_params_t *params, snd_pcm_uframes_t val);
int snd_pcm_sw_params_get_silence_size(const snd_pcm_sw_params_t *params, snd_pcm_uframes_t *val);

#endif /* !ALSA_LIBRARY_BUILD && !ALSA_PCM_OLD_SW_PARAMS_API */

/* include old API */
#ifndef ALSA_LIBRARY_BUILD
#if defined(ALSA_PCM_OLD_HW_PARAMS_API) || defined(ALSA_PCM_OLD_SW_PARAMS_API)
#include "pcm_old.h"
#endif
#endif

size_t snd_pcm_access_mask_sizeof(void);
#define snd_pcm_access_mask_alloca(ptr) __snd_alloca(ptr, snd_pcm_access_mask)
int snd_pcm_access_mask_malloc(snd_pcm_access_mask_t **ptr);
void snd_pcm_access_mask_free(snd_pcm_access_mask_t *obj);
void snd_pcm_access_mask_copy(snd_pcm_access_mask_t *dst, const snd_pcm_access_mask_t *src);
void snd_pcm_access_mask_none(snd_pcm_access_mask_t *mask);
void snd_pcm_access_mask_any(snd_pcm_access_mask_t *mask);
int snd_pcm_access_mask_test(const snd_pcm_access_mask_t *mask, snd_pcm_access_t val);
int snd_pcm_access_mask_empty(const snd_pcm_access_mask_t *mask);
void snd_pcm_access_mask_set(snd_pcm_access_mask_t *mask, snd_pcm_access_t val);
void snd_pcm_access_mask_reset(snd_pcm_access_mask_t *mask, snd_pcm_access_t val);

size_t snd_pcm_format_mask_sizeof(void);
#define snd_pcm_format_mask_alloca(ptr) __snd_alloca(ptr, snd_pcm_format_mask)
int snd_pcm_format_mask_malloc(snd_pcm_format_mask_t **ptr);
void snd_pcm_format_mask_free(snd_pcm_format_mask_t *obj);
void snd_pcm_format_mask_copy(snd_pcm_format_mask_t *dst, const snd_pcm_format_mask_t *src);
void snd_pcm_format_mask_none(snd_pcm_format_mask_t *mask);
void snd_pcm_format_mask_any(snd_pcm_format_mask_t *mask);
int snd_pcm_format_mask_test(const snd_pcm_format_mask_t *mask, snd_pcm_format_t val);
int snd_pcm_format_mask_empty(const snd_pcm_format_mask_t *mask);
void snd_pcm_format_mask_set(snd_pcm_format_mask_t *mask, snd_pcm_format_t val);
void snd_pcm_format_mask_reset(snd_pcm_format_mask_t *mask, snd_pcm_format_t val);

size_t snd_pcm_subformat_mask_sizeof(void);
#define snd_pcm_subformat_mask_alloca(ptr) __snd_alloca(ptr, snd_pcm_subformat_mask)
int snd_pcm_subformat_mask_malloc(snd_pcm_subformat_mask_t **ptr);
void snd_pcm_subformat_mask_free(snd_pcm_subformat_mask_t *obj);
void snd_pcm_subformat_mask_copy(snd_pcm_subformat_mask_t *dst, const snd_pcm_subformat_mask_t *src);
void snd_pcm_subformat_mask_none(snd_pcm_subformat_mask_t *mask);
void snd_pcm_subformat_mask_any(snd_pcm_subformat_mask_t *mask);
int snd_pcm_subformat_mask_test(const snd_pcm_subformat_mask_t *mask, snd_pcm_subformat_t val);
int snd_pcm_subformat_mask_empty(const snd_pcm_subformat_mask_t *mask);
void snd_pcm_subformat_mask_set(snd_pcm_subformat_mask_t *mask, snd_pcm_subformat_t val);
void snd_pcm_subformat_mask_reset(snd_pcm_subformat_mask_t *mask, snd_pcm_subformat_t val);

size_t snd_pcm_status_sizeof(void);
#define snd_pcm_status_alloca(ptr) __snd_alloca(ptr, snd_pcm_status)
int snd_pcm_status_malloc(snd_pcm_status_t **ptr);
void snd_pcm_status_free(snd_pcm_status_t *obj);
void snd_pcm_status_copy(snd_pcm_status_t *dst, const snd_pcm_status_t *src);
snd_pcm_state_t snd_pcm_status_get_state(const snd_pcm_status_t *obj);
void snd_pcm_status_get_trigger_tstamp(const snd_pcm_status_t *obj, snd_timestamp_t *ptr);
void snd_pcm_status_get_trigger_htstamp(const snd_pcm_status_t *obj, snd_htimestamp_t *ptr);
void snd_pcm_status_get_tstamp(const snd_pcm_status_t *obj, snd_timestamp_t *ptr);
void snd_pcm_status_get_htstamp(const snd_pcm_status_t *obj, snd_htimestamp_t *ptr);
snd_pcm_sframes_t snd_pcm_status_get_delay(const snd_pcm_status_t *obj);
snd_pcm_uframes_t snd_pcm_status_get_avail(const snd_pcm_status_t *obj);
snd_pcm_uframes_t snd_pcm_status_get_avail_max(const snd_pcm_status_t *obj);
snd_pcm_uframes_t snd_pcm_status_get_overrange(const snd_pcm_status_t *obj);

const char *snd_pcm_type_name(snd_pcm_type_t type);
const char *snd_pcm_stream_name(const snd_pcm_stream_t stream);
const char *snd_pcm_access_name(const snd_pcm_access_t _access);
const char *snd_pcm_format_name(const snd_pcm_format_t format);
const char *snd_pcm_format_description(const snd_pcm_format_t format);
const char *snd_pcm_subformat_name(const snd_pcm_subformat_t subformat);
const char *snd_pcm_subformat_description(const snd_pcm_subformat_t subformat);
snd_pcm_format_t snd_pcm_format_value(const char* name);
const char *snd_pcm_tstamp_mode_name(const snd_pcm_tstamp_t mode);
const char *snd_pcm_state_name(const snd_pcm_state_t state);

int snd_pcm_dump(snd_pcm_t *pcm, snd_output_t *out);
int snd_pcm_dump_hw_setup(snd_pcm_t *pcm, snd_output_t *out);
int snd_pcm_dump_sw_setup(snd_pcm_t *pcm, snd_output_t *out);
int snd_pcm_dump_setup(snd_pcm_t *pcm, snd_output_t *out);
int snd_pcm_hw_params_dump(snd_pcm_hw_params_t *params, snd_output_t *out);
int snd_pcm_sw_params_dump(snd_pcm_sw_params_t *params, snd_output_t *out);
int snd_pcm_status_dump(snd_pcm_status_t *status, snd_output_t *out);

int snd_pcm_mmap_begin(snd_pcm_t *pcm,
                       const snd_pcm_channel_area_t **areas,
                       snd_pcm_uframes_t *offset,
                       snd_pcm_uframes_t *frames);
snd_pcm_sframes_t snd_pcm_mmap_commit(snd_pcm_t *pcm,
                                      snd_pcm_uframes_t offset,
                                      snd_pcm_uframes_t frames);
snd_pcm_sframes_t snd_pcm_mmap_writei(snd_pcm_t *pcm, const void *buffer, snd_pcm_uframes_t size);
snd_pcm_sframes_t snd_pcm_mmap_readi(snd_pcm_t *pcm, void *buffer, snd_pcm_uframes_t size);
snd_pcm_sframes_t snd_pcm_mmap_writen(snd_pcm_t *pcm, void **bufs, snd_pcm_uframes_t size);
snd_pcm_sframes_t snd_pcm_mmap_readn(snd_pcm_t *pcm, void **bufs, snd_pcm_uframes_t size);                                                                

int snd_pcm_format_signed(snd_pcm_format_t format);
int snd_pcm_format_unsigned(snd_pcm_format_t format);
int snd_pcm_format_linear(snd_pcm_format_t format);
int snd_pcm_format_float(snd_pcm_format_t format);
int snd_pcm_format_little_endian(snd_pcm_format_t format);
int snd_pcm_format_big_endian(snd_pcm_format_t format);
int snd_pcm_format_cpu_endian(snd_pcm_format_t format);
int snd_pcm_format_width(snd_pcm_format_t format);                      /* in bits */
int snd_pcm_format_physical_width(snd_pcm_format_t format);             /* in bits */
snd_pcm_format_t snd_pcm_build_linear_format(int width, int pwidth, int unsignd, int big_endian);
ssize_t snd_pcm_format_size(snd_pcm_format_t format, size_t samples);
u_int8_t snd_pcm_format_silence(snd_pcm_format_t format);
u_int16_t snd_pcm_format_silence_16(snd_pcm_format_t format);
u_int32_t snd_pcm_format_silence_32(snd_pcm_format_t format);
u_int64_t snd_pcm_format_silence_64(snd_pcm_format_t format);
int snd_pcm_format_set_silence(snd_pcm_format_t format, void *buf, unsigned int samples);

snd_pcm_sframes_t snd_pcm_bytes_to_frames(snd_pcm_t *pcm, ssize_t bytes);
ssize_t snd_pcm_frames_to_bytes(snd_pcm_t *pcm, snd_pcm_sframes_t frames);
long snd_pcm_bytes_to_samples(snd_pcm_t *pcm, ssize_t bytes);
ssize_t snd_pcm_samples_to_bytes(snd_pcm_t *pcm, long samples);

int snd_pcm_area_silence(const snd_pcm_channel_area_t *dst_channel, snd_pcm_uframes_t dst_offset,
                         unsigned int samples, snd_pcm_format_t format);
int snd_pcm_areas_silence(const snd_pcm_channel_area_t *dst_channels, snd_pcm_uframes_t dst_offset,
                          unsigned int channels, snd_pcm_uframes_t frames, snd_pcm_format_t format);
int snd_pcm_area_copy(const snd_pcm_channel_area_t *dst_channel, snd_pcm_uframes_t dst_offset,
                      const snd_pcm_channel_area_t *src_channel, snd_pcm_uframes_t src_offset,
                      unsigned int samples, snd_pcm_format_t format);
int snd_pcm_areas_copy(const snd_pcm_channel_area_t *dst_channels, snd_pcm_uframes_t dst_offset,
                       const snd_pcm_channel_area_t *src_channels, snd_pcm_uframes_t src_offset,
                       unsigned int channels, snd_pcm_uframes_t frames, snd_pcm_format_t format);

typedef enum _snd_pcm_hook_type {
        SND_PCM_HOOK_TYPE_HW_PARAMS = 0,
        SND_PCM_HOOK_TYPE_HW_FREE,
        SND_PCM_HOOK_TYPE_CLOSE,
        SND_PCM_HOOK_TYPE_LAST = SND_PCM_HOOK_TYPE_CLOSE
} snd_pcm_hook_type_t;

typedef struct _snd_pcm_hook snd_pcm_hook_t;
typedef int (*snd_pcm_hook_func_t)(snd_pcm_hook_t *hook);
snd_pcm_t *snd_pcm_hook_get_pcm(snd_pcm_hook_t *hook);
void *snd_pcm_hook_get_private(snd_pcm_hook_t *hook);
void snd_pcm_hook_set_private(snd_pcm_hook_t *hook, void *private_data);
int snd_pcm_hook_add(snd_pcm_hook_t **hookp, snd_pcm_t *pcm,
                     snd_pcm_hook_type_t type,
                     snd_pcm_hook_func_t func, void *private_data);
int snd_pcm_hook_remove(snd_pcm_hook_t *hook);

typedef struct _snd_pcm_scope_ops {
        int (*enable)(snd_pcm_scope_t *scope);
        void (*disable)(snd_pcm_scope_t *scope);
        void (*start)(snd_pcm_scope_t *scope);
        void (*stop)(snd_pcm_scope_t *scope);
        void (*update)(snd_pcm_scope_t *scope);
        void (*reset)(snd_pcm_scope_t *scope);
        void (*close)(snd_pcm_scope_t *scope);
} snd_pcm_scope_ops_t;

snd_pcm_uframes_t snd_pcm_meter_get_bufsize(snd_pcm_t *pcm);
unsigned int snd_pcm_meter_get_channels(snd_pcm_t *pcm);
unsigned int snd_pcm_meter_get_rate(snd_pcm_t *pcm);
snd_pcm_uframes_t snd_pcm_meter_get_now(snd_pcm_t *pcm);
snd_pcm_uframes_t snd_pcm_meter_get_boundary(snd_pcm_t *pcm);
int snd_pcm_meter_add_scope(snd_pcm_t *pcm, snd_pcm_scope_t *scope);
snd_pcm_scope_t *snd_pcm_meter_search_scope(snd_pcm_t *pcm, const char *name);
int snd_pcm_scope_malloc(snd_pcm_scope_t **ptr);
void snd_pcm_scope_set_ops(snd_pcm_scope_t *scope,
                           const snd_pcm_scope_ops_t *val);
void snd_pcm_scope_set_name(snd_pcm_scope_t *scope, const char *val);
const char *snd_pcm_scope_get_name(snd_pcm_scope_t *scope);
void *snd_pcm_scope_get_callback_private(snd_pcm_scope_t *scope);
void snd_pcm_scope_set_callback_private(snd_pcm_scope_t *scope, void *val);
int snd_pcm_scope_s16_open(snd_pcm_t *pcm, const char *name,
                           snd_pcm_scope_t **scopep);
int16_t *snd_pcm_scope_s16_get_channel_buffer(snd_pcm_scope_t *scope,
                                              unsigned int channel);

typedef enum _snd_spcm_latency {
        SND_SPCM_LATENCY_STANDARD = 0,
        SND_SPCM_LATENCY_MEDIUM,
        SND_SPCM_LATENCY_REALTIME
} snd_spcm_latency_t;

typedef enum _snd_spcm_xrun_type {
        SND_SPCM_XRUN_IGNORE = 0,
        SND_SPCM_XRUN_STOP
} snd_spcm_xrun_type_t;

typedef enum _snd_spcm_duplex_type {
        SND_SPCM_DUPLEX_LIBERAL = 0,
        SND_SPCM_DUPLEX_PEDANTIC
} snd_spcm_duplex_type_t;

int snd_spcm_init(snd_pcm_t *pcm,
                  unsigned int rate,
                  unsigned int channels,
                  snd_pcm_format_t format,
                  snd_pcm_subformat_t subformat,
                  snd_spcm_latency_t latency,
                  snd_pcm_access_t _access,
                  snd_spcm_xrun_type_t xrun_type);

int snd_spcm_init_duplex(snd_pcm_t *playback_pcm,
                         snd_pcm_t *capture_pcm,
                         unsigned int rate,
                         unsigned int channels,
                         snd_pcm_format_t format,
                         snd_pcm_subformat_t subformat,
                         snd_spcm_latency_t latency,
                         snd_pcm_access_t _access,
                         snd_spcm_xrun_type_t xrun_type,
                         snd_spcm_duplex_type_t duplex_type);

int snd_spcm_init_get_params(snd_pcm_t *pcm,
                             unsigned int *rate,
                             snd_pcm_uframes_t *buffer_size,
                             snd_pcm_uframes_t *period_size);

/* Deprecated functions, for compatibility */
const char *snd_pcm_start_mode_name(snd_pcm_start_t mode) __attribute__((deprecated));
const char *snd_pcm_xrun_mode_name(snd_pcm_xrun_t mode) __attribute__((deprecated));
int snd_pcm_sw_params_set_start_mode(snd_pcm_t *pcm, snd_pcm_sw_params_t *params, snd_pcm_start_t val) __attribute__((deprecated));
snd_pcm_start_t snd_pcm_sw_params_get_start_mode(const snd_pcm_sw_params_t *params) __attribute__((deprecated));
int snd_pcm_sw_params_set_xrun_mode(snd_pcm_t *pcm, snd_pcm_sw_params_t *params, snd_pcm_xrun_t val) __attribute__((deprecated));
snd_pcm_xrun_t snd_pcm_sw_params_get_xrun_mode(const snd_pcm_sw_params_t *params) __attribute__((deprecated));
#if !defined(ALSA_LIBRARY_BUILD) && !defined(ALSA_PCM_OLD_SW_PARAMS_API)
int snd_pcm_sw_params_set_xfer_align(snd_pcm_t *pcm, snd_pcm_sw_params_t *params, snd_pcm_uframes_t val) __attribute__((deprecated));
int snd_pcm_sw_params_get_xfer_align(const snd_pcm_sw_params_t *params, snd_pcm_uframes_t *val) __attribute__((deprecated));
int snd_pcm_sw_params_set_sleep_min(snd_pcm_t *pcm, snd_pcm_sw_params_t *params, unsigned int val) __attribute__((deprecated));
int snd_pcm_sw_params_get_sleep_min(const snd_pcm_sw_params_t *params, unsigned int *val) __attribute__((deprecated));
#endif /* !ALSA_LIBRARY_BUILD && !ALSA_PCM_OLD_SW_PARAMS_API */
#if !defined(ALSA_LIBRARY_BUILD) && !defined(ALSA_PCM_OLD_HW_PARAMS_API)
int snd_pcm_hw_params_get_tick_time(const snd_pcm_hw_params_t *params, unsigned int *val, int *dir) __attribute__((deprecated));
int snd_pcm_hw_params_get_tick_time_min(const snd_pcm_hw_params_t *params, unsigned int *val, int *dir) __attribute__((deprecated));
int snd_pcm_hw_params_get_tick_time_max(const snd_pcm_hw_params_t *params, unsigned int *val, int *dir) __attribute__((deprecated));
int snd_pcm_hw_params_test_tick_time(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int val, int dir) __attribute__((deprecated));
int snd_pcm_hw_params_set_tick_time(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int val, int dir) __attribute__((deprecated));
int snd_pcm_hw_params_set_tick_time_min(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir) __attribute__((deprecated));
int snd_pcm_hw_params_set_tick_time_max(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir) __attribute__((deprecated));
int snd_pcm_hw_params_set_tick_time_minmax(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *min, int *mindir, unsigned int *max, int *maxdir) __attribute__((deprecated));
int snd_pcm_hw_params_set_tick_time_near(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir) __attribute__((deprecated));
int snd_pcm_hw_params_set_tick_time_first(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir) __attribute__((deprecated));
int snd_pcm_hw_params_set_tick_time_last(snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir) __attribute__((deprecated));
#endif /* !ALSA_LIBRARY_BUILD && !ALSA_PCM_OLD_HW_PARAMS_API */

#ifdef __cplusplus
}
#endif

#endif /* __ALSA_PCM_H */

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