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Macros | Functions | Variables
format_cache.h File Reference

Media Format Cache API. More...

Go to the source code of this file.

Macros

#define ast_format_cache_get(name)   __ast_format_cache_get((name), "ast_format_cache_get", __FILE__, __LINE__, __PRETTY_FUNCTION__)
 
#define ast_t_format_cache_get(name, tag)   __ast_format_cache_get((name), (tag), __FILE__, __LINE__, __PRETTY_FUNCTION__)
 

Functions

struct ast_format__ast_format_cache_get (const char *name, const char *tag, const char *file, int line, const char *func)
 Retrieve a named format from the cache. More...
 
struct ast_formatast_format_cache_get_by_codec (const struct ast_codec *codec)
 Retrieve a format from the cache by its codec. More...
 
struct ast_formatast_format_cache_get_slin_by_rate (unsigned int rate)
 Retrieve the best signed linear format given a sample rate. More...
 
int ast_format_cache_init (void)
 Initialize format cache support within the core. More...
 
int ast_format_cache_is_slinear (struct ast_format *format)
 Determines if a format is one of the cached slin formats. More...
 
int ast_format_cache_set (struct ast_format *format)
 Set a named format cache entry. More...
 

Variables

struct ast_formatast_format_adpcm
 Built-in cached adpcm format. More...
 
struct ast_formatast_format_alaw
 Built-in cached alaw format. More...
 
struct ast_formatast_format_codec2
 Built-in cached Codec 2 format. More...
 
struct ast_formatast_format_g719
 Built-in cached g719 format. More...
 
struct ast_formatast_format_g722
 Built-in cached g722 format. More...
 
struct ast_formatast_format_g723
 Built-in cached g723.1 format. More...
 
struct ast_formatast_format_g726
 Built-in cached g726 format. More...
 
struct ast_formatast_format_g726_aal2
 Built-in cached g726 aal2 format. More...
 
struct ast_formatast_format_g729
 Built-in cached g729 format. More...
 
struct ast_formatast_format_gsm
 Built-in cached gsm format. More...
 
struct ast_formatast_format_h261
 Built-in cached h261 format. More...
 
struct ast_formatast_format_h263
 Built-in cached h263 format. More...
 
struct ast_formatast_format_h263p
 Built-in cached h263 plus format. More...
 
struct ast_formatast_format_h264
 Built-in cached h264 format. More...
 
struct ast_formatast_format_h265
 Built-in cached h265 format. More...
 
struct ast_formatast_format_ilbc
 Built-in cached ilbc format. More...
 
struct ast_formatast_format_jpeg
 Built-in cached jpeg format. More...
 
struct ast_formatast_format_lpc10
 Built-in cached ilbc format. More...
 
struct ast_formatast_format_mp4
 Built-in cached mp4 format. More...
 
struct ast_formatast_format_none
 Built-in "null" format. More...
 
struct ast_formatast_format_opus
 Built-in cached opus format. More...
 
struct ast_formatast_format_png
 Built-in cached png format. More...
 
struct ast_formatast_format_silk12
 
struct ast_formatast_format_silk16
 
struct ast_formatast_format_silk24
 
struct ast_formatast_format_silk8
 Built-in SILK format. More...
 
struct ast_formatast_format_siren14
 Built-in cached siren14 format. More...
 
struct ast_formatast_format_siren7
 Built-in cached siren7 format. More...
 
struct ast_formatast_format_slin
 Built-in cached signed linear 8kHz format. More...
 
struct ast_formatast_format_slin12
 Built-in cached signed linear 12kHz format. More...
 
struct ast_formatast_format_slin16
 Built-in cached signed linear 16kHz format. More...
 
struct ast_formatast_format_slin192
 Built-in cached signed linear 192kHz format. More...
 
struct ast_formatast_format_slin24
 Built-in cached signed linear 24kHz format. More...
 
struct ast_formatast_format_slin32
 Built-in cached signed linear 32kHz format. More...
 
struct ast_formatast_format_slin44
 Built-in cached signed linear 44kHz format. More...
 
struct ast_formatast_format_slin48
 Built-in cached signed linear 48kHz format. More...
 
struct ast_formatast_format_slin96
 Built-in cached signed linear 96kHz format. More...
 
struct ast_formatast_format_speex
 Built-in cached speex format. More...
 
struct ast_formatast_format_speex16
 Built-in cached speex at 16kHz format. More...
 
struct ast_formatast_format_speex32
 Built-in cached speex at 32kHz format. More...
 
struct ast_formatast_format_t140
 Built-in cached t140 format. More...
 
struct ast_formatast_format_t140_red
 Built-in cached t140 red format. More...
 
struct ast_formatast_format_t38
 Built-in cached T.38 format. More...
 
struct ast_formatast_format_ulaw
 Built-in cached ulaw format. More...
 
struct ast_formatast_format_vp8
 Built-in cached vp8 format. More...
 
struct ast_formatast_format_vp9
 Built-in cached vp9 format. More...
 

Detailed Description

Media Format Cache API.

Author
Joshua Colp jcolp.nosp@m.@dig.nosp@m.ium.c.nosp@m.om

Definition in file format_cache.h.

Macro Definition Documentation

◆ ast_format_cache_get

#define ast_format_cache_get (   name)    __ast_format_cache_get((name), "ast_format_cache_get", __FILE__, __LINE__, __PRETTY_FUNCTION__)

◆ ast_t_format_cache_get

#define ast_t_format_cache_get (   name,
  tag 
)    __ast_format_cache_get((name), (tag), __FILE__, __LINE__, __PRETTY_FUNCTION__)

Definition at line 283 of file format_cache.h.

Function Documentation

◆ __ast_format_cache_get()

struct ast_format* __ast_format_cache_get ( const char *  name,
const char *  tag,
const char *  file,
int  line,
const char *  func 
)

Retrieve a named format from the cache.

Parameters
nameName of the cached format
Return values
non-NULLif found
NULLif not found
Note
The returned format has its reference count incremented. It must be dropped using ao2_ref or ao2_cleanup.

Definition at line 502 of file format_cache.c.

References __ao2_find(), ast_strlen_zero, NULL, and OBJ_SEARCH_KEY.

504 {
505  if (ast_strlen_zero(name)) {
506  return NULL;
507  }
508 
509  return __ao2_find(formats, name, OBJ_SEARCH_KEY, tag, file, line, func);
510 }
void * __ao2_find(struct ao2_container *c, const void *arg, enum search_flags flags, const char *tag, const char *file, int line, const char *func)
The arg parameter is a search key, but is not an object.
Definition: astobj2.h:1105
#define NULL
Definition: resample.c:96
Definition: file.c:69
#define ast_strlen_zero(a)
Definition: muted.c:73
static const char name[]
Definition: cdr_mysql.c:74

◆ ast_format_cache_get_by_codec()

struct ast_format* ast_format_cache_get_by_codec ( const struct ast_codec codec)

Retrieve a format from the cache by its codec.

Parameters
codecThe codec to search by
Return values
non-NULLif found
NULLif not found
Note
The returned format has its reference count incremented. It must be dropped using ao2_ref or ao2_cleanup.

Definition at line 551 of file format_cache.c.

References ao2_cleanup, ao2_iterator_destroy(), ao2_iterator_init(), ao2_iterator_next, ao2_ref, ast_format_get_codec(), format, and NULL.

Referenced by ast_format_cap_append_by_type().

552 {
553  struct ast_format *format;
554  struct ao2_iterator it;
555 
556  for (it = ao2_iterator_init(formats, 0);
557  (format = ao2_iterator_next(&it));
558  ao2_ref(format, -1)) {
559  struct ast_codec *candidate = ast_format_get_codec(format);
560  if (codec == candidate) {
561  ao2_cleanup(candidate);
563  return format;
564  }
565  ao2_cleanup(candidate);
566  }
567 
569  return NULL;
570 }
struct ast_codec * ast_format_get_codec(const struct ast_format *format)
Get the codec associated with a format.
Definition: format.c:324
Definition of a media format.
Definition: format.c:43
void ao2_iterator_destroy(struct ao2_iterator *iter)
Destroy a container iterator.
#define NULL
Definition: resample.c:96
#define ao2_ref(o, delta)
Definition: astobj2.h:464
Definition: file.c:69
#define ao2_iterator_next(iter)
Definition: astobj2.h:1933
When we need to walk through a container, we use an ao2_iterator to keep track of the current positio...
Definition: astobj2.h:1841
#define ao2_cleanup(obj)
Definition: astobj2.h:1958
static snd_pcm_format_t format
Definition: chan_alsa.c:102
Represents a media codec within Asterisk.
Definition: codec.h:42
struct ao2_iterator ao2_iterator_init(struct ao2_container *c, int flags) attribute_warn_unused_result
Create an iterator for a container.

◆ ast_format_cache_get_slin_by_rate()

struct ast_format* ast_format_cache_get_slin_by_rate ( unsigned int  rate)

Retrieve the best signed linear format given a sample rate.

Parameters
rateThe sample rate

This is a convenience function that returns one of the global ast_format_slinxxx formats.

Returns
pointer to the signed linear format
Note
The returned format has NOT had its reference count incremented.

Definition at line 512 of file format_cache.c.

References ast_format_slin, ast_format_slin12, ast_format_slin16, ast_format_slin192, ast_format_slin24, ast_format_slin32, ast_format_slin44, ast_format_slin48, and ast_format_slin96.

Referenced by ast_channel_make_compatible_helper(), audiohook_list_translate_to_slin(), audiohook_read_frame_both(), audiohook_read_frame_helper(), audiohook_read_frame_single(), audiohook_set_internal_rate(), generate_interpolated_slin(), init_jack_data(), mixmonitor_thread(), mp3_exec(), resamp_new(), set_softmix_bridge_data(), snoop_determine_format(), softmix_bridge_unsuspend(), softmix_mixing_loop(), softmix_translate_helper_change_rate(), and softmix_translate_helper_init().

513 {
514  if (rate >= 192000) {
515  return ast_format_slin192;
516  } else if (rate >= 96000) {
517  return ast_format_slin96;
518  } else if (rate >= 48000) {
519  return ast_format_slin48;
520  } else if (rate >= 44100) {
521  return ast_format_slin44;
522  } else if (rate >= 32000) {
523  return ast_format_slin32;
524  } else if (rate >= 24000) {
525  return ast_format_slin24;
526  } else if (rate >= 16000) {
527  return ast_format_slin16;
528  } else if (rate >= 12000) {
529  return ast_format_slin12;
530  }
531  return ast_format_slin;
532 }
struct ast_format * ast_format_slin192
Built-in cached signed linear 192kHz format.
Definition: format_cache.c:81
struct ast_format * ast_format_slin96
Built-in cached signed linear 96kHz format.
Definition: format_cache.c:76
struct ast_format * ast_format_slin32
Built-in cached signed linear 32kHz format.
Definition: format_cache.c:61
struct ast_format * ast_format_slin24
Built-in cached signed linear 24kHz format.
Definition: format_cache.c:56
struct ast_format * ast_format_slin48
Built-in cached signed linear 48kHz format.
Definition: format_cache.c:71
struct ast_format * ast_format_slin16
Built-in cached signed linear 16kHz format.
Definition: format_cache.c:51
struct ast_format * ast_format_slin
Built-in cached signed linear 8kHz format.
Definition: format_cache.c:41
struct ast_format * ast_format_slin44
Built-in cached signed linear 44kHz format.
Definition: format_cache.c:66
struct ast_format * ast_format_slin12
Built-in cached signed linear 12kHz format.
Definition: format_cache.c:46

◆ ast_format_cache_init()

int ast_format_cache_init ( void  )

Initialize format cache support within the core.

Return values
0success
-1failure

Definition at line 364 of file format_cache.c.

References AO2_ALLOC_OPT_LOCK_RWLOCK, ao2_container_alloc_hash, ast_register_cleanup(), CACHE_BUCKETS, format_cache_shutdown(), format_cmp_cb(), format_hash_cb(), and NULL.

Referenced by asterisk_daemon().

365 {
368  if (!formats) {
369  return -1;
370  }
371 
373 
374  return 0;
375 }
static void format_cache_shutdown(void)
Function called when the process is shutting down.
Definition: format_cache.c:311
#define NULL
Definition: resample.c:96
#define CACHE_BUCKETS
Number of buckets to use for the media format cache (should be prime for performance reasons) ...
Definition: format_cache.c:257
int ast_register_cleanup(void(*func)(void))
Register a function to be executed before Asterisk gracefully exits.
Definition: clicompat.c:19
#define ao2_container_alloc_hash(ao2_options, container_options, n_buckets, hash_fn, sort_fn, cmp_fn)
Definition: astobj2.h:1310
Definition: file.c:69
static int format_cmp_cb(void *obj, void *arg, int flags)
Definition: format_cache.c:281
static int format_hash_cb(const void *obj, int flags)
Definition: format_cache.c:262

◆ ast_format_cache_is_slinear()

int ast_format_cache_is_slinear ( struct ast_format format)

Determines if a format is one of the cached slin formats.

Parameters
formatThe format to check
Return values
0if the format is not an SLIN format
1if the format is an SLIN format

Definition at line 534 of file format_cache.c.

References ast_format_cmp(), and AST_FORMAT_CMP_EQUAL.

Referenced by __ast_read(), ast_channel_make_compatible_helper(), ast_dsp_call_progress(), ast_dsp_process(), ast_dsp_silence_noise_with_energy(), ast_frame_adjust_volume(), ast_frame_adjust_volume_float(), ast_rtp_interpret(), ast_slinfactory_init_with_format(), and ast_write_stream().

535 {
545  return 1;
546  }
547 
548  return 0;
549 }
struct ast_format * ast_format_slin192
Built-in cached signed linear 192kHz format.
Definition: format_cache.c:81
struct ast_format * ast_format_slin96
Built-in cached signed linear 96kHz format.
Definition: format_cache.c:76
struct ast_format * ast_format_slin32
Built-in cached signed linear 32kHz format.
Definition: format_cache.c:61
enum ast_format_cmp_res ast_format_cmp(const struct ast_format *format1, const struct ast_format *format2)
Compare two formats.
Definition: format.c:201
struct ast_format * ast_format_slin24
Built-in cached signed linear 24kHz format.
Definition: format_cache.c:56
struct ast_format * ast_format_slin48
Built-in cached signed linear 48kHz format.
Definition: format_cache.c:71
struct ast_format * ast_format_slin16
Built-in cached signed linear 16kHz format.
Definition: format_cache.c:51
struct ast_format * ast_format_slin
Built-in cached signed linear 8kHz format.
Definition: format_cache.c:41
struct ast_format * ast_format_slin44
Built-in cached signed linear 44kHz format.
Definition: format_cache.c:66
struct ast_format * ast_format_slin12
Built-in cached signed linear 12kHz format.
Definition: format_cache.c:46

◆ ast_format_cache_set()

int ast_format_cache_set ( struct ast_format format)

Set a named format cache entry.

Parameters
formatA pointer to the format to cache
Return values
0success
-1failure

Definition at line 474 of file format_cache.c.

References ao2_cleanup, ao2_find, ao2_link_flags, ao2_unlink_flags, ast_assert, ast_format_get_name(), ast_strlen_zero, ast_verb, lock, NULL, OBJ_NOLOCK, OBJ_SEARCH_KEY, SCOPED_AO2WRLOCK, and set_cached_format().

Referenced by AST_TEST_DEFINE().

475 {
477  struct ast_format *old_format;
478 
479  ast_assert(format != NULL);
480 
481  if (ast_strlen_zero(ast_format_get_name(format))) {
482  return -1;
483  }
484 
486  if (old_format) {
487  ao2_unlink_flags(formats, old_format, OBJ_NOLOCK);
488  }
490 
491  set_cached_format(ast_format_get_name(format), format);
492 
493  ast_verb(2, "%s cached format with name '%s'\n",
494  old_format ? "Updated" : "Created",
495  ast_format_get_name(format));
496 
497  ao2_cleanup(old_format);
498 
499  return 0;
500 }
The arg parameter is a search key, but is not an object.
Definition: astobj2.h:1105
Assume that the ao2_container is already locked.
Definition: astobj2.h:1067
Definition of a media format.
Definition: format.c:43
#define ast_assert(a)
Definition: utils.h:650
#define ao2_link_flags(container, obj, flags)
Definition: astobj2.h:1572
const char * ast_format_get_name(const struct ast_format *format)
Get the name associated with a format.
Definition: format.c:334
#define NULL
Definition: resample.c:96
#define ast_verb(level,...)
Definition: logger.h:455
#define SCOPED_AO2WRLOCK(varname, obj)
scoped lock specialization for ao2 write locks.
Definition: lock.h:612
ast_mutex_t lock
Definition: app_meetme.c:1091
static void set_cached_format(const char *name, struct ast_format *format)
Definition: format_cache.c:377
Definition: file.c:69
#define ast_strlen_zero(a)
Definition: muted.c:73
#define ao2_find(container, arg, flags)
Definition: astobj2.h:1756
#define ao2_cleanup(obj)
Definition: astobj2.h:1958
#define ao2_unlink_flags(container, obj, flags)
Definition: astobj2.h:1622

Variable Documentation

◆ ast_format_adpcm

struct ast_format* ast_format_adpcm

◆ ast_format_alaw

struct ast_format* ast_format_alaw

◆ ast_format_codec2

struct ast_format* ast_format_codec2

Built-in cached Codec 2 format.

Built-in cached Codec 2 format.

Definition at line 226 of file format_cache.c.

Referenced by codec2_sample(), load_module(), and unload_module().

◆ ast_format_g719

struct ast_format* ast_format_g719

◆ ast_format_g722

struct ast_format* ast_format_g722

◆ ast_format_g723

struct ast_format* ast_format_g723

◆ ast_format_g726

struct ast_format* ast_format_g726

◆ ast_format_g726_aal2

struct ast_format* ast_format_g726_aal2

◆ ast_format_g729

struct ast_format* ast_format_g729

◆ ast_format_gsm

struct ast_format* ast_format_gsm

◆ ast_format_h261

struct ast_format* ast_format_h261

◆ ast_format_h263

struct ast_format* ast_format_h263

◆ ast_format_h263p

struct ast_format* ast_format_h263p

◆ ast_format_h264

struct ast_format* ast_format_h264

◆ ast_format_h265

struct ast_format* ast_format_h265

Built-in cached h265 format.

Definition at line 181 of file format_cache.c.

Referenced by ast_rtp_engine_init(), and chan_pjsip_indicate().

◆ ast_format_ilbc

struct ast_format* ast_format_ilbc

◆ ast_format_jpeg

struct ast_format* ast_format_jpeg

◆ ast_format_lpc10

struct ast_format* ast_format_lpc10

◆ ast_format_mp4

struct ast_format* ast_format_mp4

◆ ast_format_none

struct ast_format* ast_format_none

◆ ast_format_opus

struct ast_format* ast_format_opus

◆ ast_format_png

struct ast_format* ast_format_png

◆ ast_format_silk12

struct ast_format* ast_format_silk12

Definition at line 252 of file format_cache.c.

◆ ast_format_silk16

struct ast_format* ast_format_silk16

Definition at line 253 of file format_cache.c.

◆ ast_format_silk24

struct ast_format* ast_format_silk24

Definition at line 254 of file format_cache.c.

◆ ast_format_silk8

struct ast_format* ast_format_silk8

Built-in SILK format.

Built-in SILK format.

Definition at line 251 of file format_cache.c.

◆ ast_format_siren14

struct ast_format* ast_format_siren14

◆ ast_format_siren7

struct ast_format* ast_format_siren7

◆ ast_format_slin

struct ast_format* ast_format_slin

Built-in cached signed linear 8kHz format.

Examples:
/tmp/asterisk-shallow/main/app.c.

Definition at line 41 of file format_cache.c.

Referenced by _moh_class_malloc(), action_originate(), alloc_playback_chan(), alsa_new(), alsa_read(), alsa_request(), announce_to_dial(), ast_audiosocket_receive_frame(), ast_channel_start_silence_generator(), ast_format_cache_get_slin_by_rate(), ast_format_compatibility_bitfield2format(), ast_format_compatibility_codec2bitfield(), ast_format_compatibility_format2bitfield(), ast_frame_slinear_sum(), ast_rtp_engine_init(), ast_slinfactory_init(), ast_speech_new(), ast_write_stream(), audiosocket_exec(), background_detect_exec(), build_conf(), chanspy_exec(), conf_run(), conf_start_record(), create_test_frame(), dahdi_format_to_cached(), dahdi_read(), dahdi_write(), dahdiscan_exec(), derive_format_from_cap(), dictate_exec(), do_notify(), do_waiting(), eagi_exec(), extenspy_exec(), fax_detect_framehook(), fax_gateway_framehook(), fax_generator_generate(), g722_sample(), generate_interpolated_slin(), generic_fax_exec(), generic_recall(), handle_participant_join(), handle_recordfile(), handle_speechcreate(), handle_speechrecognize(), holding_bridge_join(), iax_frame_wrap(), ices_exec(), isAnsweringMachine(), linear_alloc(), linear_generator(), load_module(), make_silence(), measurenoise(), meetme_menu_admin_extended(), moh_parse_options(), nbs_new(), nbs_request(), NBScat_exec(), new_outgoing(), ooh323_rtp_read(), orig_app(), orig_exten(), originate_exec(), oss_new(), oss_read(), oss_request(), participant_reaction_announcer_join(), phone_new(), phone_read(), phone_setup(), phone_write(), playtones_alloc(), playtones_generator(), prepare_bridge_media_channel(), prepare_bridge_moh_channel(), rec_request(), recalling_enter(), record_exec(), retransfer_enter(), send_waveform_to_channel(), set_read_to_slin(), silence_generator_generate(), slin8_sample(), sms_exec(), socket_process_helper(), spandsp_fax_gateway_process(), spandsp_fax_gw_t30_gen(), spandsp_fax_read(), spandsp_v21_detect(), spy_generate(), tonepair_alloc(), tonepair_generator(), and transmit_audio().

◆ ast_format_slin12

struct ast_format* ast_format_slin12

Built-in cached signed linear 12kHz format.

Definition at line 46 of file format_cache.c.

Referenced by ast_format_cache_get_slin_by_rate(), ast_rtp_engine_init(), load_module(), and originate_exec().

◆ ast_format_slin16

struct ast_format* ast_format_slin16

◆ ast_format_slin192

struct ast_format* ast_format_slin192

Built-in cached signed linear 192kHz format.

Definition at line 81 of file format_cache.c.

Referenced by ast_format_cache_get_slin_by_rate(), ast_rtp_engine_init(), load_module(), and originate_exec().

◆ ast_format_slin24

struct ast_format* ast_format_slin24

Built-in cached signed linear 24kHz format.

Definition at line 56 of file format_cache.c.

Referenced by ast_format_cache_get_slin_by_rate(), ast_rtp_engine_init(), load_module(), and originate_exec().

◆ ast_format_slin32

struct ast_format* ast_format_slin32

Built-in cached signed linear 32kHz format.

Definition at line 61 of file format_cache.c.

Referenced by ast_format_cache_get_slin_by_rate(), ast_rtp_engine_init(), load_module(), and originate_exec().

◆ ast_format_slin44

struct ast_format* ast_format_slin44

Built-in cached signed linear 44kHz format.

Definition at line 66 of file format_cache.c.

Referenced by ast_format_cache_get_slin_by_rate(), ast_rtp_engine_init(), load_module(), and originate_exec().

◆ ast_format_slin48

struct ast_format* ast_format_slin48

Built-in cached signed linear 48kHz format.

Definition at line 71 of file format_cache.c.

Referenced by ast_format_cache_get_slin_by_rate(), ast_rtp_engine_init(), load_module(), and originate_exec().

◆ ast_format_slin96

struct ast_format* ast_format_slin96

Built-in cached signed linear 96kHz format.

Definition at line 76 of file format_cache.c.

Referenced by ast_format_cache_get_slin_by_rate(), ast_rtp_engine_init(), load_module(), and originate_exec().

◆ ast_format_speex

struct ast_format* ast_format_speex

◆ ast_format_speex16

struct ast_format* ast_format_speex16

◆ ast_format_speex32

struct ast_format* ast_format_speex32

Built-in cached speex at 32kHz format.

Definition at line 141 of file format_cache.c.

Referenced by ast_rtp_engine_init(), and load_module().

◆ ast_format_t140

struct ast_format* ast_format_t140

◆ ast_format_t140_red

struct ast_format* ast_format_t140_red

◆ ast_format_t38

struct ast_format* ast_format_t38

Built-in cached T.38 format.

Definition at line 241 of file format_cache.c.

Referenced by t38_create_media_state().

◆ ast_format_ulaw

struct ast_format* ast_format_ulaw

◆ ast_format_vp8

struct ast_format* ast_format_vp8

◆ ast_format_vp9

struct ast_format* ast_format_vp9

Built-in cached vp9 format.

Definition at line 196 of file format_cache.c.

Referenced by ast_rtp_engine_init(), and chan_pjsip_indicate().