code.delx.au - pulseaudio/blob - src/pulse/def.h

   1 #ifndef foodefhfoo
   2 #define foodefhfoo
   3
   4 /* $Id$ */
   5
   6 /***
   7   This file is part of PulseAudio.
   8
   9   Copyright 2004-2006 Lennart Poettering
  10   Copyright 2006 Pierre Ossman <ossman@cendio.se> for Cendio AB
  11
  12   PulseAudio is free software; you can redistribute it and/or modify
  13   it under the terms of the GNU Lesser General Public License as
  14   published by the Free Software Foundation; either version 2.1 of the
  15   License, or (at your option) any later version.
  16
  17   PulseAudio is distributed in the hope that it will be useful, but
  18   WITHOUT ANY WARRANTY; without even the implied warranty of
  19   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  20   Lesser General Public License for more details.
  21
  22   You should have received a copy of the GNU Lesser General Public
  23   License along with PulseAudio; if not, write to the Free Software
  24   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  25   USA.
  26 ***/
  27
  28 #include <inttypes.h>
  29 #include <sys/time.h>
  30 #include <time.h>
  31
  32 #include <pulse/cdecl.h>
  33 #include <pulse/sample.h>
  34
  35 /** \file
  36  * Global definitions */
  37
  38 PA_C_DECL_BEGIN
  39
  40 /** The state of a connection context */
  41 typedef enum pa_context_state {
  42     PA_CONTEXT_UNCONNECTED,    /**< The context hasn't been connected yet */
  43     PA_CONTEXT_CONNECTING,     /**< A connection is being established */
  44     PA_CONTEXT_AUTHORIZING,    /**< The client is authorizing itself to the daemon */
  45     PA_CONTEXT_SETTING_NAME,   /**< The client is passing its application name to the daemon */
  46     PA_CONTEXT_READY,          /**< The connection is established, the context is ready to execute operations */
  47     PA_CONTEXT_FAILED,         /**< The connection failed or was disconnected */
  48     PA_CONTEXT_TERMINATED      /**< The connection was terminated cleanly */
  49 } pa_context_state_t;
  50
  51 /** Return non-zero if the passed state is one of the connected states */
  52 static inline int PA_CONTEXT_IS_GOOD(pa_context_state_t x) {
  53     return
  54         x == PA_CONTEXT_CONNECTING ||
  55         x == PA_CONTEXT_AUTHORIZING ||
  56         x == PA_CONTEXT_SETTING_NAME ||
  57         x == PA_CONTEXT_READY;
  58 }
  59
  60 /** The state of a stream */
  61 typedef enum pa_stream_state {
  62     PA_STREAM_UNCONNECTED, /**< The stream is not yet connected to any sink or source */
  63     PA_STREAM_CREATING,     /**< The stream is being created */
  64     PA_STREAM_READY,        /**< The stream is established, you may pass audio data to it now */
  65     PA_STREAM_FAILED,       /**< An error occured that made the stream invalid */
  66     PA_STREAM_TERMINATED    /**< The stream has been terminated cleanly */
  67 } pa_stream_state_t;
  68
  69 /** Return non-zero if the passed state is one of the connected states */
  70 static inline int PA_STREAM_IS_GOOD(pa_stream_state_t x) {
  71     return
  72         x == PA_STREAM_CREATING ||
  73         x == PA_STREAM_READY;
  74 }
  75
  76 /** The state of an operation */
  77 typedef enum pa_operation_state {
  78     PA_OPERATION_RUNNING,      /**< The operation is still running */
  79     PA_OPERATION_DONE,         /**< The operation has been completed */
  80     PA_OPERATION_CANCELED      /**< The operation has been canceled */
  81 } pa_operation_state_t;
  82
  83 /** An invalid index */
  84 #define PA_INVALID_INDEX ((uint32_t) -1)
  85
  86 /** Some special flags for contexts. */
  87 typedef enum pa_context_flags {
  88     PA_CONTEXT_NOAUTOSPAWN = 1 /**< Disabled autospawning of the PulseAudio daemon if required */
  89 } pa_context_flags_t;
  90
  91 /** The direction of a pa_stream object */
  92 typedef enum pa_stream_direction {
  93     PA_STREAM_NODIRECTION,   /**< Invalid direction */
  94     PA_STREAM_PLAYBACK,      /**< Playback stream */
  95     PA_STREAM_RECORD,        /**< Record stream */
  96     PA_STREAM_UPLOAD         /**< Sample upload stream */
  97 } pa_stream_direction_t;
  98
  99 /** Some special flags for stream connections. */
 100 typedef enum pa_stream_flags {
 101     PA_STREAM_START_CORKED = 1,       /**< Create the stream corked, requiring an explicit pa_stream_cork() call to uncork it. */
 102     PA_STREAM_INTERPOLATE_TIMING = 2, /**< Interpolate the latency for
 103                                        * this stream. When enabled,
 104                                        * pa_stream_get_latency() and
 105                                        * pa_stream_get_time() will try
 106                                        * to estimate the current
 107                                        * record/playback time based on
 108                                        * the local time that passed
 109                                        * since the last timing info
 110                                        * update.  Using this option
 111                                        * has the advantage of not
 112                                        * requiring a whole roundtrip
 113                                        * when the current
 114                                        * playback/recording time is
 115                                        * needed. Consider using this
 116                                        * option when requesting
 117                                        * latency information
 118                                        * frequently. This is
 119                                        * especially useful on long
 120                                        * latency network
 121                                        * connections. It makes a lot
 122                                        * of sense to combine this
 123                                        * option with
 124                                        * PA_STREAM_AUTO_TIMING_UPDATE. */
 125     PA_STREAM_NOT_MONOTONOUS = 4,    /**< Don't force the time to
 126                                       * increase monotonically. If
 127                                       * this option is enabled,
 128                                       * pa_stream_get_time() will not
 129                                       * necessarily return always
 130                                       * monotonically increasing time
 131                                       * values on each call. This may
 132                                       * confuse applications which
 133                                       * cannot deal with time going
 134                                       * 'backwards', but has the
 135                                       * advantage that bad transport
 136                                       * latency estimations that
 137                                       * caused the time to to jump
 138                                       * ahead can be corrected
 139                                       * quickly, without the need to
 140                                       * wait. */
 141     PA_STREAM_AUTO_TIMING_UPDATE = 8, /**< If set timing update requests
 142                                        * are issued periodically
 143                                        * automatically. Combined with
 144                                        * PA_STREAM_INTERPOLATE_TIMING
 145                                        * you will be able to query the
 146                                        * current time and latency with
 147                                        * pa_stream_get_time() and
 148                                        * pa_stream_get_latency() at
 149                                        * all times without a packet
 150                                        * round trip.*/
 151     PA_STREAM_NO_REMAP_CHANNELS = 16, /**< Don't remap channels by
 152                                        * their name, instead map them
 153                                        * simply by their
 154                                        * index. Implies
 155                                        * PA_STREAM_NO_REMIX_CHANNELS. Only
 156                                        * supported when the server is
 157                                        * at least PA 0.9.8. It is
 158                                        * ignored on older
 159                                        * servers.\since 0.9.8 */
 160     PA_STREAM_NO_REMIX_CHANNELS = 32, /**< When remapping channels by
 161                                        * name, don't upmix or downmix
 162                                        * them to related
 163                                        * channels. Copy them into
 164                                        * matching channels of the
 165                                        * device 1:1. Only supported
 166                                        * when the server is at least
 167                                        * PA 0.9.8. It is ignored on
 168                                        * older servers. \since
 169                                        * 0.9.8 */
 170     PA_STREAM_FIX_FORMAT = 64, /**< Use the sample format of the
 171                                 * sink/device this stream is being
 172                                 * connected to, and possibly ignore
 173                                 * the format the sample spec contains
 174                                 * -- but you still have to pass a
 175                                 * valid value in it as a hint to
 176                                 * PulseAudio what would suit your
 177                                 * stream best. If this is used you
 178                                 * should query the used sample format
 179                                 * after creating the stream by using
 180                                 * pa_stream_get_sample_spec(). Also,
 181                                 * if you specified manual buffer
 182                                 * metrics it is recommended to update
 183                                 * them with
 184                                 * pa_stream_set_buffer_attr() to
 185                                 * compensate for the changed frame
 186                                 * sizes. Only supported when the
 187                                 * server is at least PA 0.9.8. It is
 188                                 * ignored on older servers. \since
 189                                 * 0.9.8 */
 190
 191     PA_STREAM_FIX_RATE = 128, /**< Use the sample rate of the sink,
 192                                * and possibly ignore the rate the
 193                                * sample spec contains. Usage similar
 194                                * to PA_STREAM_FIX_FORMAT.Only
 195                                * supported when the server is at least
 196                                * PA 0.9.8. It is ignored on older
 197                                * servers. \since 0.9.8 */
 198
 199     PA_STREAM_FIX_CHANNELS = 256, /**< Use the number of channels and
 200                                * the channel map of the sink, and
 201                                * possibly ignore the number of
 202                                * channels and the map the sample spec
 203                                * and the passed channel map
 204                                * contains. Usage similar to
 205                                * PA_STREAM_FIX_FORMAT. Only supported
 206                                * when the server is at least PA
 207                                * 0.9.8. It is ignored on older
 208                                * servers. \since 0.9.8 */
 209     PA_STREAM_DONT_MOVE = 512, /**< Don't allow moving of this stream to
 210                               * another sink/device. Useful if you use
 211                               * any of the PA_STREAM_FIX_ flags and
 212                               * want to make sure that resampling
 213                               * never takes place -- which might
 214                               * happen if the stream is moved to
 215                               * another sink/source whith a different
 216                               * sample spec/channel map. Only
 217                               * supported when the server is at least
 218                               * PA 0.9.8. It is ignored on older
 219                               * servers. \since 0.9.8 */
 220     PA_STREAM_VARIABLE_RATE = 1024, /**< Allow dynamic changing of the
 221                                      * sampling rate during playback
 222                                      * with
 223                                      * pa_stream_update_sample_rate(). Only
 224                                      * supported when the server is at
 225                                      * least PA 0.9.8. It is ignored
 226                                      * on older servers. \since
 227                                      * 0.9.8 */
 228     PA_STREAM_PEAK_DETECT = 2048, /**< Find peaks instead of
 229                                    * resampling. \since 0.9.11 */
 230
 231     PA_STREAM_START_MUTED = 4096,  /**< Create in muted state. \since 0.9.11 */
 232
 233
 234     PA_STREAM_ADJUST_LATENCY = 8192, /**< Try to adjust the latency of
 235                                       * the sink/source based on the
 236                                       * requested buffer metrics and
 237                                       * adjust buffer metrics
 238                                       * accordingly. \since 0.9.11 */
 239 } pa_stream_flags_t;
 240
 241 /** Playback and record buffer metrics */
 242 typedef struct pa_buffer_attr {
 243     uint32_t maxlength;      /**< Maximum length of the
 244                               * buffer. Setting this to 0 will
 245                               * initialize this to the maximum value
 246                               * supported by server, which is
 247                               * recommended. */
 248     uint32_t tlength;        /**< Playback only: target length of the
 249                               * buffer. The server tries to assure
 250                               * that at least tlength bytes are always
 251                               * available in the buffer. It is
 252                               * recommended to set this to 0, which
 253                               * will initialize this to a value that
 254                               * is deemed sensible by the
 255                               * server. However, this value will
 256                               * default to something like 2s, i.e. for
 257                               * applications that have specific
 258                               * latency requirements this value should
 259                               * be set to the maximum latency that the
 260                               * application can deal with.  */
 261     uint32_t prebuf;         /**< Playback only: pre-buffering. The
 262                               * server does not start with playback
 263                               * before at least prebug bytes are
 264                               * available in the buffer. It is
 265                               * recommended to set this to 0, which
 266                               * will initialize this to the same value
 267                               * as tlength, whatever that may be. */
 268     uint32_t minreq;         /**< Playback only: minimum request. The
 269                               * server does not request less than
 270                               * minreq bytes from the client, instead
 271                               * waits until the buffer is free enough
 272                               * to request more bytes at once. It is
 273                               * recommended to set this to 0, which
 274                               * will initialize this to a value that
 275                               * is deemed sensible by the server. */
 276     uint32_t fragsize;       /**< Recording only: fragment size. The
 277                               * server sends data in blocks of
 278                               * fragsize bytes size. Large values
 279                               * deminish interactivity with other
 280                               * operations on the connection context
 281                               * but decrease control overhead. It is
 282                               * recommended to set this to 0, which
 283                               * will initialize this to a value that
 284                               * is deemed sensible by the
 285                               * server. However, this value will
 286                               * default to something like 2s, i.e. for
 287                               * applications that have specific
 288                               * latency requirements this value should
 289                               * be set to the maximum latency that the
 290                               * application can deal with. */
 291 } pa_buffer_attr;
 292
 293 /** Error values as used by pa_context_errno(). Use pa_strerror() to convert these values to human readable strings */
 294 enum {
 295     PA_OK = 0,                     /**< No error */
 296     PA_ERR_ACCESS,                 /**< Access failure */
 297     PA_ERR_COMMAND,                /**< Unknown command */
 298     PA_ERR_INVALID,                /**< Invalid argument */
 299     PA_ERR_EXIST,                  /**< Entity exists */
 300     PA_ERR_NOENTITY,               /**< No such entity */
 301     PA_ERR_CONNECTIONREFUSED,      /**< Connection refused */
 302     PA_ERR_PROTOCOL,               /**< Protocol error */
 303     PA_ERR_TIMEOUT,                /**< Timeout */
 304     PA_ERR_AUTHKEY,                /**< No authorization key */
 305     PA_ERR_INTERNAL,               /**< Internal error */
 306     PA_ERR_CONNECTIONTERMINATED,   /**< Connection terminated */
 307     PA_ERR_KILLED,                 /**< Entity killed */
 308     PA_ERR_INVALIDSERVER,          /**< Invalid server */
 309     PA_ERR_MODINITFAILED,          /**< Module initialization failed */
 310     PA_ERR_BADSTATE,               /**< Bad state */
 311     PA_ERR_NODATA,                 /**< No data */
 312     PA_ERR_VERSION,                /**< Incompatible protocol version */
 313     PA_ERR_TOOLARGE,               /**< Data too large */
 314     PA_ERR_NOTSUPPORTED,           /**< Operation not supported \since 0.9.5 */
 315     PA_ERR_UNKNOWN,                /**< The error code was unknown to the client */
 316     PA_ERR_MAX                     /**< Not really an error but the first invalid error code */
 317 };
 318
 319 /** Subscription event mask, as used by pa_context_subscribe() */
 320 typedef enum pa_subscription_mask {
 321     PA_SUBSCRIPTION_MASK_NULL = 0,               /**< No events */
 322     PA_SUBSCRIPTION_MASK_SINK = 1,               /**< Sink events */
 323     PA_SUBSCRIPTION_MASK_SOURCE = 2,             /**< Source events */
 324     PA_SUBSCRIPTION_MASK_SINK_INPUT = 4,         /**< Sink input events */
 325     PA_SUBSCRIPTION_MASK_SOURCE_OUTPUT = 8,      /**< Source output events */
 326     PA_SUBSCRIPTION_MASK_MODULE = 16,            /**< Module events */
 327     PA_SUBSCRIPTION_MASK_CLIENT = 32,            /**< Client events */
 328     PA_SUBSCRIPTION_MASK_SAMPLE_CACHE = 64,      /**< Sample cache events */
 329     PA_SUBSCRIPTION_MASK_SERVER = 128,           /**< Other global server changes. */
 330     PA_SUBSCRIPTION_MASK_AUTOLOAD = 256,         /**< Autoload table events. */
 331     PA_SUBSCRIPTION_MASK_ALL = 511               /**< Catch all events */
 332 } pa_subscription_mask_t;
 333
 334 /** Subscription event types, as used by pa_context_subscribe() */
 335 typedef enum pa_subscription_event_type {
 336     PA_SUBSCRIPTION_EVENT_SINK = 0,           /**< Event type: Sink */
 337     PA_SUBSCRIPTION_EVENT_SOURCE = 1,         /**< Event type: Source */
 338     PA_SUBSCRIPTION_EVENT_SINK_INPUT = 2,     /**< Event type: Sink input */
 339     PA_SUBSCRIPTION_EVENT_SOURCE_OUTPUT = 3,  /**< Event type: Source output */
 340     PA_SUBSCRIPTION_EVENT_MODULE = 4,         /**< Event type: Module */
 341     PA_SUBSCRIPTION_EVENT_CLIENT = 5,         /**< Event type: Client */
 342     PA_SUBSCRIPTION_EVENT_SAMPLE_CACHE = 6,   /**< Event type: Sample cache item */
 343     PA_SUBSCRIPTION_EVENT_SERVER = 7,         /**< Event type: Global server change, only occuring with PA_SUBSCRIPTION_EVENT_CHANGE. */
 344     PA_SUBSCRIPTION_EVENT_AUTOLOAD = 8,       /**< Event type: Autoload table changes. */
 345     PA_SUBSCRIPTION_EVENT_FACILITY_MASK = 15, /**< A mask to extract the event type from an event value */
 346
 347     PA_SUBSCRIPTION_EVENT_NEW = 0,            /**< A new object was created */
 348     PA_SUBSCRIPTION_EVENT_CHANGE = 16,        /**< A property of the object was modified */
 349     PA_SUBSCRIPTION_EVENT_REMOVE = 32,        /**< An object was removed */
 350     PA_SUBSCRIPTION_EVENT_TYPE_MASK = 16+32   /**< A mask to extract the event operation from an event value */
 351 } pa_subscription_event_type_t;
 352
 353 /** Return one if an event type t matches an event mask bitfield */
 354 #define pa_subscription_match_flags(m, t) (!!((m) & (1 << ((t) & PA_SUBSCRIPTION_EVENT_FACILITY_MASK))))
 355
 356 /** A structure for all kinds of timing information of a stream. See
 357  * pa_stream_update_timing_info() and pa_stream_get_timing_info(). The
 358  * total output latency a sample that is written with
 359  * pa_stream_write() takes to be played may be estimated by
 360  * sink_usec+buffer_usec+transport_usec. (where buffer_usec is defined
 361  * as pa_bytes_to_usec(write_index-read_index)) The output buffer
 362  * which buffer_usec relates to may be manipulated freely (with
 363  * pa_stream_write()'s seek argument, pa_stream_flush() and friends),
 364  * the buffers sink_usec and source_usec relate to are first-in
 365  * first-out (FIFO) buffers which cannot be flushed or manipulated in
 366  * any way. The total input latency a sample that is recorded takes to
 367  * be delivered to the application is:
 368  * source_usec+buffer_usec+transport_usec-sink_usec. (Take care of
 369  * sign issues!) When connected to a monitor source sink_usec contains
 370  * the latency of the owning sink. The two latency estimations
 371  * described here are implemented in pa_stream_get_latency(). Please
 372  * note that this structure can be extended as part of evolutionary
 373  * API updates at any time in any new release.*/
 374 typedef struct pa_timing_info {
 375     struct timeval timestamp; /**< The time when this timing info structure was current */
 376     int synchronized_clocks;  /**< Non-zero if the local and the
 377                                * remote machine have synchronized
 378                                * clocks. If synchronized clocks are
 379                                * detected transport_usec becomes much
 380                                * more reliable. However, the code that
 381                                * detects synchronized clocks is very
 382                                * limited und unreliable itself. */
 383
 384     pa_usec_t sink_usec;      /**< Time in usecs a sample takes to be played on the sink. For playback streams and record streams connected to a monitor source. */
 385     pa_usec_t source_usec;    /**< Time in usecs a sample takes from being recorded to being delivered to the application. Only for record streams. */
 386     pa_usec_t transport_usec; /**< Estimated time in usecs a sample takes to be transferred to/from the daemon. For both playback and record streams. */
 387
 388     int playing;              /**< Non-zero when the stream is
 389                                * currently not underrun and data is
 390                                * being passed on to the device. Only
 391                                * for playback streams. This field does
 392                                * not say whether the data is actually
 393                                * already being played. To determine
 394                                * this check whether since_underrun
 395                                * (converted to usec) is larger than
 396                                * sink_usec.*/
 397
 398     int write_index_corrupt;  /**< Non-zero if write_index is not
 399                                * up-to-date because a local write
 400                                * command that corrupted it has been
 401                                * issued in the time since this latency
 402                                * info was current . Only write
 403                                * commands with SEEK_RELATIVE_ON_READ
 404                                * and SEEK_RELATIVE_END can corrupt
 405                                * write_index. */
 406     int64_t write_index;      /**< Current write index into the
 407                                * playback buffer in bytes. Think twice before
 408                                * using this for seeking purposes: it
 409                                * might be out of date a the time you
 410                                * want to use it. Consider using
 411                                * PA_SEEK_RELATIVE instead.  */
 412
 413     int read_index_corrupt;   /**< Non-zero if read_index is not
 414                                * up-to-date because a local pause or
 415                                * flush request that corrupted it has
 416                                * been issued in the time since this
 417                                * latency info was current. */
 418
 419     int64_t read_index;       /**< Current read index into the
 420                                * playback buffer in bytes. Think twice before
 421                                * using this for seeking purposes: it
 422                                * might be out of date a the time you
 423                                * want to use it. Consider using
 424                                * PA_SEEK_RELATIVE_ON_READ
 425                                * instead. */
 426
 427     pa_usec_t configured_sink_usec;   /**< The static configured latency for
 428                                 * the sink. \since 0.9.11 */
 429     pa_usec_t configured_source_usec; /**< The static configured latency for
 430                                 * the source. \since 0.9.11 */
 431
 432     int64_t since_underrun;    /**< Bytes that were handed to the sink
 433                                   since the last underrun happened, or
 434                                   since playback started again after
 435                                   the last underrun. playing will tell
 436                                   you which case it is. \since
 437                                   0.9.11 */
 438
 439 } pa_timing_info;
 440
 441 /** A structure for the spawn api. This may be used to integrate auto
 442  * spawned daemons into your application. For more information see
 443  * pa_context_connect(). When spawning a new child process the
 444  * waitpid() is used on the child's PID. The spawn routine will not
 445  * block or ignore SIGCHLD signals, since this cannot be done in a
 446  * thread compatible way. You might have to do this in
 447  * prefork/postfork. */
 448 typedef struct pa_spawn_api {
 449     void (*prefork)(void);     /**< Is called just before the fork in the parent process. May be NULL. */
 450     void (*postfork)(void);    /**< Is called immediately after the fork in the parent process. May be NULL.*/
 451     void (*atfork)(void);      /**< Is called immediately after the
 452                                 * fork in the child process. May be
 453                                 * NULL. It is not safe to close all
 454                                 * file descriptors in this function
 455                                 * unconditionally, since a UNIX socket
 456                                 * (created using socketpair()) is
 457                                 * passed to the new process. */
 458 } pa_spawn_api;
 459
 460 /** Seek type for pa_stream_write(). */
 461 typedef enum pa_seek_mode {
 462     PA_SEEK_RELATIVE = 0,           /**< Seek relatively to the write index */
 463     PA_SEEK_ABSOLUTE = 1,           /**< Seek relatively to the start of the buffer queue */
 464     PA_SEEK_RELATIVE_ON_READ = 2,   /**< Seek relatively to the read index.  */
 465     PA_SEEK_RELATIVE_END = 3        /**< Seek relatively to the current end of the buffer queue. */
 466 } pa_seek_mode_t;
 467
 468 /** Special sink flags. */
 469 typedef enum pa_sink_flags {
 470     PA_SINK_HW_VOLUME_CTRL = 1,   /**< Supports hardware volume control */
 471     PA_SINK_LATENCY = 2,          /**< Supports latency querying */
 472     PA_SINK_HARDWARE = 4,         /**< Is a hardware sink of some kind, in contrast to "virtual"/software sinks \since 0.9.3 */
 473     PA_SINK_NETWORK = 8,          /**< Is a networked sink of some kind. \since 0.9.7 */
 474     PA_SINK_HW_MUTE_CTRL = 16,    /**< Supports hardware mute control \since 0.9.11 */
 475     PA_SINK_DECIBEL_VOLUME = 32   /**< Volume can be translated to dB with pa_sw_volume_to_dB() \since 0.9.11 */
 476 } pa_sink_flags_t;
 477
 478 /** Special source flags.  */
 479 typedef enum pa_source_flags {
 480     PA_SOURCE_HW_VOLUME_CTRL = 1,  /**< Supports hardware volume control */
 481     PA_SOURCE_LATENCY = 2,         /**< Supports latency querying */
 482     PA_SOURCE_HARDWARE = 4,        /**< Is a hardware source of some kind, in contrast to "virtual"/software source \since 0.9.3 */
 483     PA_SOURCE_NETWORK = 8,         /**< Is a networked sink of some kind. \since 0.9.7 */
 484     PA_SOURCE_HW_MUTE_CTRL = 16,   /**< Supports hardware mute control \since 0.9.11 */
 485     PA_SOURCE_DECIBEL_VOLUME = 32  /**< Volume can be translated to dB with pa_sw_volume_to_dB() \since 0.9.11 */
 486 } pa_source_flags_t;
 487
 488 /** A generic free() like callback prototype */
 489 typedef void (*pa_free_cb_t)(void *p);
 490
 491 PA_C_DECL_END
 492
 493 #endif