Asterisk - The Open Source Telephony Project GIT-master-2de1a68
Data Structures | Macros | Enumerations | Functions
res_prometheus.h File Reference

Asterisk Prometheus Metrics. More...

#include "asterisk/lock.h"
#include "asterisk/linkedlists.h"
#include "asterisk/stringfields.h"
Include dependency graph for res_prometheus.h:
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Go to the source code of this file.

Data Structures

struct  prometheus_callback
 Defines a callback that will be invoked when the HTTP route is called. More...
 
struct  prometheus_general_config
 Prometheus general configuration. More...
 
struct  prometheus_label
 A label that further defines a metric. More...
 
struct  prometheus_metric
 An actual, honest to god, metric. More...
 
struct  prometheus_metrics_provider
 A function table for a metrics provider. More...
 

Macros

#define PROMETHEUS_MAX_LABEL_LENGTH   128
 How long a label value can be. More...
 
#define PROMETHEUS_MAX_LABELS   8
 How many labels a single metric can have. More...
 
#define PROMETHEUS_MAX_NAME_LENGTH   64
 How long a label name can be. More...
 
#define PROMETHEUS_MAX_VALUE_LENGTH   32
 How large of a value we can store. More...
 
#define PROMETHEUS_METRIC_SET_LABEL(metric, label, n, v)
 Convenience macro for setting a label / value in a metric. More...
 
#define PROMETHEUS_METRIC_STATIC_INITIALIZATION(mtype, n, h, cb)
 Convenience macro for initializing a metric on the stack. More...
 

Enumerations

enum  prometheus_metric_allocation_strategy { PROMETHEUS_METRIC_ALLOCD = 0 , PROMETHEUS_METRIC_MALLOCD }
 How the metric was allocated. More...
 
enum  prometheus_metric_type { PROMETHEUS_METRIC_COUNTER = 0 , PROMETHEUS_METRIC_GAUGE }
 Prometheus metric type. More...
 

Functions

int prometheus_callback_register (struct prometheus_callback *callback)
 
void prometheus_callback_unregister (struct prometheus_callback *callback)
 Remove a registered callback. More...
 
struct prometheus_metricprometheus_counter_create (const char *name, const char *help)
 Create a malloc'd counter metric. More...
 
struct prometheus_metricprometheus_gauge_create (const char *name, const char *help)
 Create a malloc'd gauge metric. More...
 
void * prometheus_general_config_alloc (void)
 Allocate a new configuration object. More...
 
struct prometheus_general_configprometheus_general_config_get (void)
 Retrieve the current configuration of the module. More...
 
void prometheus_general_config_set (struct prometheus_general_config *config)
 Set the configuration for the module. More...
 
void prometheus_metric_free (struct prometheus_metric *metric)
 Destroy a metric and all its children. More...
 
int prometheus_metric_register (struct prometheus_metric *metric)
 
int prometheus_metric_registered_count (void)
 
void prometheus_metric_to_string (struct prometheus_metric *metric, struct ast_str **output)
 Convert a metric (and its children) into Prometheus compatible text. More...
 
int prometheus_metric_unregister (struct prometheus_metric *metric)
 Remove a registered metric. More...
 
void prometheus_metrics_provider_register (const struct prometheus_metrics_provider *provider)
 Register a metrics provider. More...
 

Detailed Description

Asterisk Prometheus Metrics.

This module provides the base APIs and functionality for exposing a metrics route in Asterisk's HTTP server suitable for consumption by a Prometheus server. It does not provide any metrics itself.

Definition in file res_prometheus.h.

Macro Definition Documentation

◆ PROMETHEUS_MAX_LABEL_LENGTH

#define PROMETHEUS_MAX_LABEL_LENGTH   128

How long a label value can be.

Definition at line 49 of file res_prometheus.h.

◆ PROMETHEUS_MAX_LABELS

#define PROMETHEUS_MAX_LABELS   8

How many labels a single metric can have.

Definition at line 39 of file res_prometheus.h.

◆ PROMETHEUS_MAX_NAME_LENGTH

#define PROMETHEUS_MAX_NAME_LENGTH   64

How long a label name can be.

Definition at line 44 of file res_prometheus.h.

◆ PROMETHEUS_MAX_VALUE_LENGTH

#define PROMETHEUS_MAX_VALUE_LENGTH   32

How large of a value we can store.

Definition at line 54 of file res_prometheus.h.

◆ PROMETHEUS_METRIC_SET_LABEL

#define PROMETHEUS_METRIC_SET_LABEL (   metric,
  label,
  n,
 
)
Value:
do { \
ast_assert((label) < PROMETHEUS_MAX_LABELS); \
ast_copy_string((metric)->labels[(label)].name, (n), sizeof((metric)->labels[(label)].name)); \
ast_copy_string((metric)->labels[(label)].value, (v), sizeof((metric)->labels[(label)].value)); \
} while (0)
static const char name[]
Definition: format_mp3.c:68
#define PROMETHEUS_MAX_LABELS
How many labels a single metric can have.
int value
Definition: syslog.c:37

Convenience macro for setting a label / value in a metric.

When creating nested metrics, it's helpful to set their label after they have been declared but before they have been registered. This macro acts as a convenience function to set the labels properly on a declared metric.

Note
Setting labels after registration will lead to a "bad time"

Example Usage:

test_gauge_child_two, 0, "key_one", "value_two");
test_gauge_child_two, 1, "key_two", "value_two");
#define PROMETHEUS_METRIC_SET_LABEL(metric, label, n, v)
Convenience macro for setting a label / value in a metric.
Parameters
metricThe metric to set the label on
labelPosition of the label to set
nName of the label
vValue of the label

Definition at line 313 of file res_prometheus.h.

◆ PROMETHEUS_METRIC_STATIC_INITIALIZATION

#define PROMETHEUS_METRIC_STATIC_INITIALIZATION (   mtype,
  n,
  h,
  cb 
)

Convenience macro for initializing a metric on the stack.

When initializing a metric on the stack, various fields have to be provided to initialize the metric correctly. This macro can be used to simplify the process.

Example Usage:

struct prometheus_metric test_counter_one =
"test_counter_one",
"A test counter",
NULL);
struct prometheus_metric test_counter_two =
"test_counter_two",
"A test counter",
#define PROMETHEUS_METRIC_STATIC_INITIALIZATION(mtype, n, h, cb)
Convenience macro for initializing a metric on the stack.
@ PROMETHEUS_METRIC_COUNTER
A metric whose value always goes up.
#define NULL
Definition: resample.c:96
An actual, honest to god, metric.
static void metric_values_get_counter_value_cb(struct prometheus_metric *metric)
Parameters
mtypeThe metric type. See prometheus_metric_type
nName of the metric
hHelp text for the metric
cbCallback function. Optional; may be NULL

Definition at line 281 of file res_prometheus.h.

Enumeration Type Documentation

◆ prometheus_metric_allocation_strategy

How the metric was allocated.

Note
Clearly, you don't want to get this wrong.
Enumerator
PROMETHEUS_METRIC_ALLOCD 

The metric was allocated on the stack.

PROMETHEUS_METRIC_MALLOCD 

The metric was allocated on the heap.

Definition at line 138 of file res_prometheus.h.

138 {
139 /*!
140 * \brief The metric was allocated on the stack
141 */
143 /*!
144 * \brief The metric was allocated on the heap
145 */
147};
@ PROMETHEUS_METRIC_ALLOCD
The metric was allocated on the stack.
@ PROMETHEUS_METRIC_MALLOCD
The metric was allocated on the heap.

◆ prometheus_metric_type

Prometheus metric type.

Note
Clearly, at some point, we should support summaries and histograms. As an initial implementation, counters / gauges give us quite a bit of functionality.
Enumerator
PROMETHEUS_METRIC_COUNTER 

A metric whose value always goes up.

PROMETHEUS_METRIC_GAUGE 

A metric whose value can bounce around like a jackrabbit.

Definition at line 122 of file res_prometheus.h.

122 {
123 /*!
124 * \brief A metric whose value always goes up
125 */
127 /*!
128 * \brief A metric whose value can bounce around like a jackrabbit
129 */
131};
@ PROMETHEUS_METRIC_GAUGE
A metric whose value can bounce around like a jackrabbit.

Function Documentation

◆ prometheus_callback_register()

int prometheus_callback_register ( struct prometheus_callback callback)

Register a metric callback

Parameters
callbackThe callback to register
Return values
0success
-1error

Definition at line 535 of file res_prometheus.c.

536{
538
539 if (!callback || !callback->callback_fn || ast_strlen_zero(callback->name)) {
540 return -1;
541 }
542
543 AST_VECTOR_APPEND(&callbacks, callback);
544
545 return 0;
546}
ast_mutex_t lock
Definition: app_sla.c:331
#define SCOPED_MUTEX(varname, lock)
scoped lock specialization for mutexes
Definition: lock.h:589
struct @468 callbacks
static ast_mutex_t scrape_lock
Lock that protects data structures during an HTTP scrape.
static force_inline int attribute_pure ast_strlen_zero(const char *s)
Definition: strings.h:65
void(* callback_fn)(struct ast_str **output)
The callback function to invoke.
const char * name
The name of our callback (always useful for debugging)
#define AST_VECTOR_APPEND(vec, elem)
Append an element to a vector, growing the vector if needed.
Definition: vector.h:256

References ast_strlen_zero(), AST_VECTOR_APPEND, prometheus_callback::callback_fn, callbacks, lock, prometheus_callback::name, SCOPED_MUTEX, and scrape_lock.

Referenced by AST_TEST_DEFINE(), bridge_metrics_init(), channel_metrics_init(), and endpoint_metrics_init().

◆ prometheus_callback_unregister()

void prometheus_callback_unregister ( struct prometheus_callback callback)

Remove a registered callback.

Parameters
callbackThe callback to unregister

Definition at line 548 of file res_prometheus.c.

549{
551 int i;
552
553 for (i = 0; i < AST_VECTOR_SIZE(&callbacks); i++) {
555
556 if (!strcmp(callback->name, entry->name)) {
558 return;
559 }
560 }
561}
Definition: search.h:40
Defines a callback that will be invoked when the HTTP route is called.
#define AST_VECTOR_SIZE(vec)
Get the number of elements in a vector.
Definition: vector.h:609
#define AST_VECTOR_REMOVE(vec, idx, preserve_ordered)
Remove an element from a vector by index.
Definition: vector.h:412
#define AST_VECTOR_GET(vec, idx)
Get an element from a vector.
Definition: vector.h:680

References AST_VECTOR_GET, AST_VECTOR_REMOVE, AST_VECTOR_SIZE, callbacks, lock, prometheus_callback::name, SCOPED_MUTEX, and scrape_lock.

Referenced by AST_TEST_DEFINE(), bridge_metrics_unload_cb(), channel_metrics_unload_cb(), and endpoint_metrics_unload_cb().

◆ prometheus_counter_create()

struct prometheus_metric * prometheus_counter_create ( const char *  name,
const char *  help 
)

Create a malloc'd counter metric.

Note
The metric must be registered after creation
Parameters
nameThe name of the metric
helpHelp text for the metric
Return values
prometheus_metricon success
NULLon error

Definition at line 452 of file res_prometheus.c.

453{
454 struct prometheus_metric *metric;
455
457 if (!metric) {
458 return NULL;
459 }
461
462 return metric;
463}
static struct prometheus_metric * prometheus_metric_create(const char *name, const char *help)
const char * help
Pointer to a static string defining this metric's help text.
enum prometheus_metric_type type
What type of metric we are.

References prometheus_metric::help, name, NULL, PROMETHEUS_METRIC_COUNTER, prometheus_metric_create(), and prometheus_metric::type.

Referenced by AST_TEST_DEFINE().

◆ prometheus_gauge_create()

struct prometheus_metric * prometheus_gauge_create ( const char *  name,
const char *  help 
)

Create a malloc'd gauge metric.

Note
The metric must be registered after creation
Parameters
nameThe name of the metric
helpHelp text for the metric
Return values
prometheus_metricon success
NULLon error

Definition at line 439 of file res_prometheus.c.

440{
441 struct prometheus_metric *metric;
442
444 if (!metric) {
445 return NULL;
446 }
448
449 return metric;
450}

References prometheus_metric::help, name, NULL, prometheus_metric_create(), PROMETHEUS_METRIC_GAUGE, and prometheus_metric::type.

Referenced by AST_TEST_DEFINE().

◆ prometheus_general_config_alloc()

void * prometheus_general_config_alloc ( void  )

Allocate a new configuration object.

The returned object is an AO2 ref counted object

Return values
NULLon error
configon success

Definition at line 726 of file res_prometheus.c.

727{
729
731 if (!config || ast_string_field_init(config, 32)) {
732 return NULL;
733 }
734
735 return config;
736}
#define ao2_alloc(data_size, destructor_fn)
Definition: astobj2.h:409
static const char config[]
Definition: chan_ooh323.c:111
static void prometheus_general_config_dtor(void *obj)
#define ast_string_field_init(x, size)
Initialize a field pool and fields.
Definition: stringfields.h:359
Prometheus general configuration.

References ao2_alloc, ast_string_field_init, config, NULL, and prometheus_general_config_dtor().

Referenced by config_alloc(), and module_config_alloc().

◆ prometheus_general_config_get()

struct prometheus_general_config * prometheus_general_config_get ( void  )

Retrieve the current configuration of the module.

config is an AO2 ref counted object

Note
This should primarily be done for testing purposes.
Return values
NULLon error
configon success

Definition at line 738 of file res_prometheus.c.

739{
741
742 if (!mod_cfg) {
743 return NULL;
744 }
745 ao2_bump(mod_cfg->general);
746
747 return mod_cfg->general;
748}
#define ao2_cleanup(obj)
Definition: astobj2.h:1934
#define ao2_global_obj_ref(holder)
Get a reference to the object stored in the global holder.
Definition: astobj2.h:918
#define ao2_bump(obj)
Bump refcount on an AO2 object by one, returning the object.
Definition: astobj2.h:480
The configuration settings for this module.
Definition: cdr.c:264
#define RAII_VAR(vartype, varname, initval, dtor)
Declare a variable that will call a destructor function when it goes out of scope.
Definition: utils.h:941

References ao2_bump, ao2_cleanup, ao2_global_obj_ref, NULL, and RAII_VAR.

Referenced by prometheus_show_status(), reload_module(), and test_init_cb().

◆ prometheus_general_config_set()

void prometheus_general_config_set ( struct prometheus_general_config config)

Set the configuration for the module.

This is not a ref-stealing function. The reference count to config will be incremented as a result of calling this method.

Note
This should primarily be done for testing purposes

Definition at line 750 of file res_prometheus.c.

751{
753
754 if (!mod_cfg) {
755 return;
756 }
757 ao2_replace(mod_cfg->general, config);
759}
#define ao2_replace(dst, src)
Replace one object reference with another cleaning up the original.
Definition: astobj2.h:501
static void prometheus_config_post_apply(void)
Post-apply callback for the config framework.

References ao2_cleanup, ao2_global_obj_ref, ao2_replace, config, prometheus_config_post_apply(), and RAII_VAR.

Referenced by AST_TEST_DEFINE(), test_cleanup_cb(), and test_init_cb().

◆ prometheus_metric_free()

void prometheus_metric_free ( struct prometheus_metric metric)

Destroy a metric and all its children.

Note
If you still want the children, make sure you remove the head of the children list first.
Parameters
metricThe metric to destroy

Definition at line 393 of file res_prometheus.c.

394{
395 struct prometheus_metric *child;
396
397 if (!metric) {
398 return;
399 }
400
401 while ((child = AST_LIST_REMOVE_HEAD(&metric->children, entry))) {
403 }
404 ast_mutex_destroy(&metric->lock);
405
407 return;
408 } else if (metric->allocation_strategy == PROMETHEUS_METRIC_MALLOCD) {
409 ast_free(metric);
410 }
411}
#define ast_free(a)
Definition: astmm.h:180
#define AST_LIST_REMOVE_HEAD(head, field)
Removes and returns the head entry from a list.
Definition: linkedlists.h:833
#define ast_mutex_destroy(a)
Definition: lock.h:188
void prometheus_metric_free(struct prometheus_metric *metric)
Destroy a metric and all its children.
struct prometheus_metric::@270 children
A list of children metrics.
enum prometheus_metric_allocation_strategy allocation_strategy
How this metric was allocated.
ast_mutex_t lock
A lock protecting the metric value.

References prometheus_metric::allocation_strategy, ast_free, AST_LIST_REMOVE_HEAD, ast_mutex_destroy, prometheus_metric::children, prometheus_metric::lock, PROMETHEUS_METRIC_ALLOCD, prometheus_metric_free(), and PROMETHEUS_METRIC_MALLOCD.

Referenced by AST_TEST_DEFINE(), prometheus_metric_free(), prometheus_metric_free_wrapper(), prometheus_metric_unregister(), and unload_module().

◆ prometheus_metric_register()

int prometheus_metric_register ( struct prometheus_metric metric)

Register a metric for collection

Parameters
metricThe metric to register
Return values
0success
-1error

Definition at line 288 of file res_prometheus.c.

289{
291 int i;
292
293 if (!metric) {
294 return -1;
295 }
296
297 for (i = 0; i < AST_VECTOR_SIZE(&metrics); i++) {
298 struct prometheus_metric *existing = AST_VECTOR_GET(&metrics, i);
299 struct prometheus_metric *child;
300
301 if (prometheus_metric_cmp(existing, metric)) {
303 "Refusing registration of existing Prometheus metric: %s\n",
304 metric->name);
305 return -1;
306 }
307
308 AST_LIST_TRAVERSE(&existing->children, child, entry) {
309 if (prometheus_metric_cmp(child, metric)) {
311 "Refusing registration of existing Prometheus metric: %s\n",
312 metric->name);
313 return -1;
314 }
315 }
316
317 if (!strcmp(metric->name, existing->name)) {
318 ast_debug(3, "Nesting metric '%s' as child (%p) under existing (%p)\n",
319 metric->name, metric, existing);
320 AST_LIST_INSERT_TAIL(&existing->children, metric, entry);
321 return 0;
322 }
323 }
324
325 ast_debug(3, "Tracking new root metric '%s'\n", metric->name);
326 if (AST_VECTOR_APPEND(&metrics, metric)) {
327 ast_log(AST_LOG_WARNING, "Failed to grow vector to make room for Prometheus metric: %s\n",
328 metric->name);
329 return -1;
330 }
331
332 return 0;
333}
#define ast_log
Definition: astobj2.c:42
#define AST_LOG_WARNING
#define ast_debug(level,...)
Log a DEBUG message.
#define AST_LOG_NOTICE
#define AST_LIST_TRAVERSE(head, var, field)
Loops over (traverses) the entries in a list.
Definition: linkedlists.h:491
#define AST_LIST_INSERT_TAIL(head, elm, field)
Appends a list entry to the tail of a list.
Definition: linkedlists.h:731
struct @467 metrics
static int prometheus_metric_cmp(struct prometheus_metric *left, struct prometheus_metric *right)
char name[PROMETHEUS_MAX_NAME_LENGTH]
Our metric name.

References ast_debug, AST_LIST_INSERT_TAIL, AST_LIST_TRAVERSE, ast_log, AST_LOG_NOTICE, AST_LOG_WARNING, AST_VECTOR_APPEND, AST_VECTOR_GET, AST_VECTOR_SIZE, prometheus_metric::children, lock, metrics, prometheus_metric::name, prometheus_metric_cmp(), SCOPED_MUTEX, and scrape_lock.

Referenced by AST_TEST_DEFINE(), and prometheus_config_post_apply().

◆ prometheus_metric_registered_count()

int prometheus_metric_registered_count ( void  )

The current number of registered metrics

Return values
Thecurrent number of registered metrics

Definition at line 281 of file res_prometheus.c.

282{
284
285 return AST_VECTOR_SIZE(&metrics);
286}

References AST_VECTOR_SIZE, lock, metrics, SCOPED_MUTEX, and scrape_lock.

Referenced by AST_TEST_DEFINE().

◆ prometheus_metric_to_string()

void prometheus_metric_to_string ( struct prometheus_metric metric,
struct ast_str **  output 
)

Convert a metric (and its children) into Prometheus compatible text.

Parameters
metricThe metric to convert to a string
[out]outputThe ast_str string to populate with the metric(s)

Definition at line 521 of file res_prometheus.c.

523{
524 struct prometheus_metric *child;
525
526 ast_str_append(output, 0, "# HELP %s %s\n", metric->name, metric->help);
527 ast_str_append(output, 0, "# TYPE %s %s\n", metric->name,
529 prometheus_metric_full_to_string(metric, output);
530 AST_LIST_TRAVERSE(&metric->children, child, entry) {
532 }
533}
static void prometheus_metric_full_to_string(struct prometheus_metric *metric, struct ast_str **output)
static const char * prometheus_metric_type_to_string(enum prometheus_metric_type type)
int ast_str_append(struct ast_str **buf, ssize_t max_len, const char *fmt,...)
Append to a thread local dynamic string.
Definition: strings.h:1139

References AST_LIST_TRAVERSE, ast_str_append(), prometheus_metric::children, prometheus_metric::help, prometheus_metric::name, prometheus_metric_full_to_string(), prometheus_metric_type_to_string(), and prometheus_metric::type.

Referenced by AST_TEST_DEFINE(), bridges_scrape_cb(), channels_scrape_cb(), endpoints_scrape_cb(), http_callback(), prometheus_metric_callback(), and scrape_metrics().

◆ prometheus_metric_unregister()

int prometheus_metric_unregister ( struct prometheus_metric metric)

Remove a registered metric.

Parameters
metricThe metric to unregister
Note
Unregistering also destroys the metric, if found
Return values
0The metric was found, unregistered, and disposed of
-1The metric was not found

Definition at line 335 of file res_prometheus.c.

336{
337 if (!metric) {
338 return -1;
339 }
340
341 {
343 int i;
344
345 ast_debug(3, "Removing metric '%s'\n", metric->name);
346 for (i = 0; i < AST_VECTOR_SIZE(&metrics); i++) {
347 struct prometheus_metric *existing = AST_VECTOR_GET(&metrics, i);
348
349 /*
350 * If this is a complete match, remove the matching metric
351 * and place its children back into the list
352 */
353 if (prometheus_metric_cmp(existing, metric)) {
354 struct prometheus_metric *root;
355
357 root = AST_LIST_REMOVE_HEAD(&existing->children, entry);
358 if (root) {
359 struct prometheus_metric *child;
360 AST_LIST_TRAVERSE_SAFE_BEGIN(&existing->children, child, entry) {
362 AST_LIST_INSERT_TAIL(&root->children, child, entry);
363 }
365 AST_VECTOR_INSERT_AT(&metrics, i, root);
366 }
367 prometheus_metric_free(existing);
368 return 0;
369 }
370
371 /*
372 * Name match, but labels don't match. Find the matching entry with
373 * labels and remove it along with all of its children
374 */
375 if (!strcmp(existing->name, metric->name)) {
376 struct prometheus_metric *child;
377
378 AST_LIST_TRAVERSE_SAFE_BEGIN(&existing->children, child, entry) {
379 if (prometheus_metric_cmp(child, metric)) {
382 return 0;
383 }
384 }
386 }
387 }
388 }
389
390 return -1;
391}
#define AST_LIST_TRAVERSE_SAFE_END
Closes a safe loop traversal block.
Definition: linkedlists.h:615
#define AST_LIST_TRAVERSE_SAFE_BEGIN(head, var, field)
Loops safely over (traverses) the entries in a list.
Definition: linkedlists.h:529
#define AST_LIST_REMOVE_CURRENT(field)
Removes the current entry from a list during a traversal.
Definition: linkedlists.h:557
#define AST_VECTOR_INSERT_AT(vec, idx, elem)
Insert an element at a specific position in a vector, growing the vector if needed.
Definition: vector.h:338

References ast_debug, AST_LIST_INSERT_TAIL, AST_LIST_REMOVE_CURRENT, AST_LIST_REMOVE_HEAD, AST_LIST_TRAVERSE_SAFE_BEGIN, AST_LIST_TRAVERSE_SAFE_END, AST_VECTOR_GET, AST_VECTOR_INSERT_AT, AST_VECTOR_REMOVE, AST_VECTOR_SIZE, prometheus_metric::children, lock, metrics, prometheus_metric::name, prometheus_metric_cmp(), prometheus_metric_free(), SCOPED_MUTEX, and scrape_lock.

Referenced by AST_TEST_DEFINE(), prometheus_config_post_apply(), and prometheus_metric_free_wrapper().

◆ prometheus_metrics_provider_register()

void prometheus_metrics_provider_register ( const struct prometheus_metrics_provider provider)

Register a metrics provider.

Parameters
providerThe provider function table to register

Definition at line 871 of file res_prometheus.c.

872{
874}
static struct prometheus_metrics_provider provider
Definition: bridges.c:201
struct @469 providers

References AST_VECTOR_APPEND, provider, and providers.

Referenced by bridge_metrics_init(), channel_metrics_init(), cli_init(), endpoint_metrics_init(), and pjsip_outbound_registration_metrics_init().