This file is indexed.

/usr/include/alsa/mixer.h is in libasound2-dev 1.0.25-1ubuntu10.

This file is owned by root:root, with mode 0o644.

The actual contents of the file can be viewed below.

  1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
/**
 * \file include/mixer.h
 * \brief Application interface library for the ALSA driver
 * \author Jaroslav Kysela <perex@perex.cz>
 * \author Abramo Bagnara <abramo@alsa-project.org>
 * \author Takashi Iwai <tiwai@suse.de>
 * \date 1998-2001
 *
 * Application interface library for the ALSA driver
 */
/*
 *   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_MIXER_H
#define __ALSA_MIXER_H

#ifdef __cplusplus
extern "C" {
#endif

/**
 *  \defgroup Mixer Mixer Interface
 *  The mixer interface.
 *  \{
 */

/** Mixer handle */
typedef struct _snd_mixer snd_mixer_t;
/** Mixer elements class handle */
typedef struct _snd_mixer_class snd_mixer_class_t;
/** Mixer element handle */
typedef struct _snd_mixer_elem snd_mixer_elem_t;

/** 
 * \brief Mixer callback function
 * \param mixer Mixer handle
 * \param mask event mask
 * \param elem related mixer element (if any)
 * \return 0 on success otherwise a negative error code
 */
typedef int (*snd_mixer_callback_t)(snd_mixer_t *ctl,
				    unsigned int mask,
				    snd_mixer_elem_t *elem);

/** 
 * \brief Mixer element callback function
 * \param elem Mixer element
 * \param mask event mask
 * \return 0 on success otherwise a negative error code
 */
typedef int (*snd_mixer_elem_callback_t)(snd_mixer_elem_t *elem,
					 unsigned int mask);

/**
 * \brief Compare function for sorting mixer elements
 * \param e1 First element
 * \param e2 Second element
 * \return -1 if e1 < e2, 0 if e1 == e2, 1 if e1 > e2
 */
typedef int (*snd_mixer_compare_t)(const snd_mixer_elem_t *e1,
				   const snd_mixer_elem_t *e2);

/**
 * \brief Event callback for the mixer class
 * \param class_ Mixer class
 * \param mask Event mask (SND_CTL_EVENT_*)
 * \param helem HCTL element which invoked the event
 * \param melem Mixer element associated to HCTL element
 * \return zero if success, otherwise a negative error value
 */
typedef int (*snd_mixer_event_t)(snd_mixer_class_t *class_, unsigned int mask,
				 snd_hctl_elem_t *helem, snd_mixer_elem_t *melem);


/** Mixer element type */
typedef enum _snd_mixer_elem_type {
	/* Simple mixer elements */
	SND_MIXER_ELEM_SIMPLE,
	SND_MIXER_ELEM_LAST = SND_MIXER_ELEM_SIMPLE
} snd_mixer_elem_type_t;

int snd_mixer_open(snd_mixer_t **mixer, int mode);
int snd_mixer_close(snd_mixer_t *mixer);
snd_mixer_elem_t *snd_mixer_first_elem(snd_mixer_t *mixer);
snd_mixer_elem_t *snd_mixer_last_elem(snd_mixer_t *mixer);
int snd_mixer_handle_events(snd_mixer_t *mixer);
int snd_mixer_attach(snd_mixer_t *mixer, const char *name);
int snd_mixer_attach_hctl(snd_mixer_t *mixer, snd_hctl_t *hctl);
int snd_mixer_detach(snd_mixer_t *mixer, const char *name);
int snd_mixer_detach_hctl(snd_mixer_t *mixer, snd_hctl_t *hctl);
int snd_mixer_get_hctl(snd_mixer_t *mixer, const char *name, snd_hctl_t **hctl);
int snd_mixer_poll_descriptors_count(snd_mixer_t *mixer);
int snd_mixer_poll_descriptors(snd_mixer_t *mixer, struct pollfd *pfds, unsigned int space);
int snd_mixer_poll_descriptors_revents(snd_mixer_t *mixer, struct pollfd *pfds, unsigned int nfds, unsigned short *revents);
int snd_mixer_load(snd_mixer_t *mixer);
void snd_mixer_free(snd_mixer_t *mixer);
int snd_mixer_wait(snd_mixer_t *mixer, int timeout);
int snd_mixer_set_compare(snd_mixer_t *mixer, snd_mixer_compare_t msort);
void snd_mixer_set_callback(snd_mixer_t *obj, snd_mixer_callback_t val);
void * snd_mixer_get_callback_private(const snd_mixer_t *obj);
void snd_mixer_set_callback_private(snd_mixer_t *obj, void * val);
unsigned int snd_mixer_get_count(const snd_mixer_t *obj);
int snd_mixer_class_unregister(snd_mixer_class_t *clss);

snd_mixer_elem_t *snd_mixer_elem_next(snd_mixer_elem_t *elem);
snd_mixer_elem_t *snd_mixer_elem_prev(snd_mixer_elem_t *elem);
void snd_mixer_elem_set_callback(snd_mixer_elem_t *obj, snd_mixer_elem_callback_t val);
void * snd_mixer_elem_get_callback_private(const snd_mixer_elem_t *obj);
void snd_mixer_elem_set_callback_private(snd_mixer_elem_t *obj, void * val);
snd_mixer_elem_type_t snd_mixer_elem_get_type(const snd_mixer_elem_t *obj);

int snd_mixer_class_register(snd_mixer_class_t *class_, snd_mixer_t *mixer);
int snd_mixer_elem_new(snd_mixer_elem_t **elem,
		       snd_mixer_elem_type_t type,
		       int compare_weight,
		       void *private_data,
		       void (*private_free)(snd_mixer_elem_t *elem));
int snd_mixer_elem_add(snd_mixer_elem_t *elem, snd_mixer_class_t *class_);
int snd_mixer_elem_remove(snd_mixer_elem_t *elem);
void snd_mixer_elem_free(snd_mixer_elem_t *elem);
int snd_mixer_elem_info(snd_mixer_elem_t *elem);
int snd_mixer_elem_value(snd_mixer_elem_t *elem);
int snd_mixer_elem_attach(snd_mixer_elem_t *melem, snd_hctl_elem_t *helem);
int snd_mixer_elem_detach(snd_mixer_elem_t *melem, snd_hctl_elem_t *helem);
int snd_mixer_elem_empty(snd_mixer_elem_t *melem);
void *snd_mixer_elem_get_private(const snd_mixer_elem_t *melem);

size_t snd_mixer_class_sizeof(void);
/** \hideinitializer
 * \brief allocate an invalid #snd_mixer_class_t using standard alloca
 * \param ptr returned pointer
 */
#define snd_mixer_class_alloca(ptr) __snd_alloca(ptr, snd_mixer_class)
int snd_mixer_class_malloc(snd_mixer_class_t **ptr);
void snd_mixer_class_free(snd_mixer_class_t *obj);
void snd_mixer_class_copy(snd_mixer_class_t *dst, const snd_mixer_class_t *src);
snd_mixer_t *snd_mixer_class_get_mixer(const snd_mixer_class_t *class_);
snd_mixer_event_t snd_mixer_class_get_event(const snd_mixer_class_t *class_);
void *snd_mixer_class_get_private(const snd_mixer_class_t *class_);
snd_mixer_compare_t snd_mixer_class_get_compare(const snd_mixer_class_t *class_);
int snd_mixer_class_set_event(snd_mixer_class_t *class_, snd_mixer_event_t event);
int snd_mixer_class_set_private(snd_mixer_class_t *class_, void *private_data);
int snd_mixer_class_set_private_free(snd_mixer_class_t *class_, void (*private_free)(snd_mixer_class_t *class_));
int snd_mixer_class_set_compare(snd_mixer_class_t *class_, snd_mixer_compare_t compare);

/**
 *  \defgroup SimpleMixer Simple Mixer Interface
 *  \ingroup Mixer
 *  The simple mixer interface.
 *  \{
 */

/* Simple mixer elements API */

/** Mixer simple element channel identifier */
typedef enum _snd_mixer_selem_channel_id {
	/** Unknown */
	SND_MIXER_SCHN_UNKNOWN = -1,
	/** Front left */
	SND_MIXER_SCHN_FRONT_LEFT = 0,
	/** Front right */
	SND_MIXER_SCHN_FRONT_RIGHT,
	/** Rear left */
	SND_MIXER_SCHN_REAR_LEFT,
	/** Rear right */
	SND_MIXER_SCHN_REAR_RIGHT,
	/** Front center */
	SND_MIXER_SCHN_FRONT_CENTER,
	/** Woofer */
	SND_MIXER_SCHN_WOOFER,
	/** Side Left */
	SND_MIXER_SCHN_SIDE_LEFT,
	/** Side Right */
	SND_MIXER_SCHN_SIDE_RIGHT,
	/** Rear Center */
	SND_MIXER_SCHN_REAR_CENTER,
	SND_MIXER_SCHN_LAST = 31,
	/** Mono (Front left alias) */
	SND_MIXER_SCHN_MONO = SND_MIXER_SCHN_FRONT_LEFT
} snd_mixer_selem_channel_id_t;

/** Mixer simple element - register options - abstraction level */
enum snd_mixer_selem_regopt_abstract {
	/** no abstraction - try use all universal controls from driver */
	SND_MIXER_SABSTRACT_NONE = 0,
	/** basic abstraction - Master,PCM,CD,Aux,Record-Gain etc. */
	SND_MIXER_SABSTRACT_BASIC,
};

/** Mixer simple element - register options */
struct snd_mixer_selem_regopt {
	/** structure version */
	int ver;
	/** v1: abstract layer selection */
	enum snd_mixer_selem_regopt_abstract abstract;
	/** v1: device name (must be NULL when playback_pcm or capture_pcm != NULL) */
	const char *device;
	/** v1: playback PCM connected to mixer device (NULL == none) */
	snd_pcm_t *playback_pcm;
	/** v1: capture PCM connected to mixer device (NULL == none) */
	snd_pcm_t *capture_pcm;
};

/** Mixer simple element identifier */
typedef struct _snd_mixer_selem_id snd_mixer_selem_id_t;

const char *snd_mixer_selem_channel_name(snd_mixer_selem_channel_id_t channel);

int snd_mixer_selem_register(snd_mixer_t *mixer,
			     struct snd_mixer_selem_regopt *options,
			     snd_mixer_class_t **classp);
void snd_mixer_selem_get_id(snd_mixer_elem_t *element,
			    snd_mixer_selem_id_t *id);
const char *snd_mixer_selem_get_name(snd_mixer_elem_t *elem);
unsigned int snd_mixer_selem_get_index(snd_mixer_elem_t *elem);
snd_mixer_elem_t *snd_mixer_find_selem(snd_mixer_t *mixer,
				       const snd_mixer_selem_id_t *id);

int snd_mixer_selem_is_active(snd_mixer_elem_t *elem);
int snd_mixer_selem_is_playback_mono(snd_mixer_elem_t *elem);
int snd_mixer_selem_has_playback_channel(snd_mixer_elem_t *obj, snd_mixer_selem_channel_id_t channel);
int snd_mixer_selem_is_capture_mono(snd_mixer_elem_t *elem);
int snd_mixer_selem_has_capture_channel(snd_mixer_elem_t *obj, snd_mixer_selem_channel_id_t channel);
int snd_mixer_selem_get_capture_group(snd_mixer_elem_t *elem);
int snd_mixer_selem_has_common_volume(snd_mixer_elem_t *elem);
int snd_mixer_selem_has_playback_volume(snd_mixer_elem_t *elem);
int snd_mixer_selem_has_playback_volume_joined(snd_mixer_elem_t *elem);
int snd_mixer_selem_has_capture_volume(snd_mixer_elem_t *elem);
int snd_mixer_selem_has_capture_volume_joined(snd_mixer_elem_t *elem);
int snd_mixer_selem_has_common_switch(snd_mixer_elem_t *elem);
int snd_mixer_selem_has_playback_switch(snd_mixer_elem_t *elem);
int snd_mixer_selem_has_playback_switch_joined(snd_mixer_elem_t *elem);
int snd_mixer_selem_has_capture_switch(snd_mixer_elem_t *elem);
int snd_mixer_selem_has_capture_switch_joined(snd_mixer_elem_t *elem);
int snd_mixer_selem_has_capture_switch_exclusive(snd_mixer_elem_t *elem);

int snd_mixer_selem_ask_playback_vol_dB(snd_mixer_elem_t *elem, long value, long *dBvalue);
int snd_mixer_selem_ask_capture_vol_dB(snd_mixer_elem_t *elem, long value, long *dBvalue);
int snd_mixer_selem_ask_playback_dB_vol(snd_mixer_elem_t *elem, long dBvalue, int dir, long *value);
int snd_mixer_selem_ask_capture_dB_vol(snd_mixer_elem_t *elem, long dBvalue, int dir, long *value);
int snd_mixer_selem_get_playback_volume(snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, long *value);
int snd_mixer_selem_get_capture_volume(snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, long *value);
int snd_mixer_selem_get_playback_dB(snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, long *value);
int snd_mixer_selem_get_capture_dB(snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, long *value);
int snd_mixer_selem_get_playback_switch(snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, int *value);
int snd_mixer_selem_get_capture_switch(snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, int *value);
int snd_mixer_selem_set_playback_volume(snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, long value);
int snd_mixer_selem_set_capture_volume(snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, long value);
int snd_mixer_selem_set_playback_dB(snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, long value, int dir);
int snd_mixer_selem_set_capture_dB(snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, long value, int dir);
int snd_mixer_selem_set_playback_volume_all(snd_mixer_elem_t *elem, long value);
int snd_mixer_selem_set_capture_volume_all(snd_mixer_elem_t *elem, long value);
int snd_mixer_selem_set_playback_dB_all(snd_mixer_elem_t *elem, long value, int dir);
int snd_mixer_selem_set_capture_dB_all(snd_mixer_elem_t *elem, long value, int dir);
int snd_mixer_selem_set_playback_switch(snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, int value);
int snd_mixer_selem_set_capture_switch(snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, int value);
int snd_mixer_selem_set_playback_switch_all(snd_mixer_elem_t *elem, int value);
int snd_mixer_selem_set_capture_switch_all(snd_mixer_elem_t *elem, int value);
int snd_mixer_selem_get_playback_volume_range(snd_mixer_elem_t *elem, 
					      long *min, long *max);
int snd_mixer_selem_get_playback_dB_range(snd_mixer_elem_t *elem, 
					  long *min, long *max);
int snd_mixer_selem_set_playback_volume_range(snd_mixer_elem_t *elem, 
					      long min, long max);
int snd_mixer_selem_get_capture_volume_range(snd_mixer_elem_t *elem, 
					     long *min, long *max);
int snd_mixer_selem_get_capture_dB_range(snd_mixer_elem_t *elem, 
					 long *min, long *max);
int snd_mixer_selem_set_capture_volume_range(snd_mixer_elem_t *elem, 
					     long min, long max);

int snd_mixer_selem_is_enumerated(snd_mixer_elem_t *elem);
int snd_mixer_selem_is_enum_playback(snd_mixer_elem_t *elem);
int snd_mixer_selem_is_enum_capture(snd_mixer_elem_t *elem);
int snd_mixer_selem_get_enum_items(snd_mixer_elem_t *elem);
int snd_mixer_selem_get_enum_item_name(snd_mixer_elem_t *elem, unsigned int idx, size_t maxlen, char *str);
int snd_mixer_selem_get_enum_item(snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, unsigned int *idxp);
int snd_mixer_selem_set_enum_item(snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, unsigned int idx);

size_t snd_mixer_selem_id_sizeof(void);
/** \hideinitializer
 * \brief allocate an invalid #snd_mixer_selem_id_t using standard alloca
 * \param ptr returned pointer
 */
#define snd_mixer_selem_id_alloca(ptr) __snd_alloca(ptr, snd_mixer_selem_id)
int snd_mixer_selem_id_malloc(snd_mixer_selem_id_t **ptr);
void snd_mixer_selem_id_free(snd_mixer_selem_id_t *obj);
void snd_mixer_selem_id_copy(snd_mixer_selem_id_t *dst, const snd_mixer_selem_id_t *src);
const char *snd_mixer_selem_id_get_name(const snd_mixer_selem_id_t *obj);
unsigned int snd_mixer_selem_id_get_index(const snd_mixer_selem_id_t *obj);
void snd_mixer_selem_id_set_name(snd_mixer_selem_id_t *obj, const char *val);
void snd_mixer_selem_id_set_index(snd_mixer_selem_id_t *obj, unsigned int val);

/** \} */

/** \} */

#ifdef __cplusplus
}
#endif

#endif /* __ALSA_MIXER_H */