Wed Jan 8 2020 09:49:51

Asterisk developer's documentation


timing.c
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1 /*
2  * Asterisk -- An open source telephony toolkit.
3  *
4  * Copyright (C) 2008 - 2009, Digium, Inc.
5  *
6  * Kevin P. Fleming <kpfleming@digium.com>
7  * Russell Bryant <russell@digium.com>
8  *
9  * See http://www.asterisk.org for more information about
10  * the Asterisk project. Please do not directly contact
11  * any of the maintainers of this project for assistance;
12  * the project provides a web site, mailing lists and IRC
13  * channels for your use.
14  *
15  * This program is free software, distributed under the terms of
16  * the GNU General Public License Version 2. See the LICENSE file
17  * at the top of the source tree.
18  */
19 
20 /*! \file
21  *
22  * \brief Timing source management
23  *
24  * \author Kevin P. Fleming <kpfleming@digium.com>
25  * \author Russell Bryant <russell@digium.com>
26  */
27 
28 /*** MODULEINFO
29  <support_level>core</support_level>
30  ***/
31 
32 #include "asterisk.h"
33 
34 ASTERISK_FILE_VERSION(__FILE__, "$Revision: 377881 $")
35 
36 #include "asterisk/_private.h"
37 
38 #include "asterisk/timing.h"
39 #include "asterisk/lock.h"
40 #include "asterisk/cli.h"
41 #include "asterisk/utils.h"
42 #include "asterisk/time.h"
43 #include "asterisk/heap.h"
44 #include "asterisk/module.h"
45 #include "asterisk/poll-compat.h"
46 
47 struct timing_holder {
48  /*! Do _not_ move this from the beginning of the struct. */
49  ssize_t __heap_index;
50  struct ast_module *mod;
52 };
53 
54 static struct ast_heap *timing_interfaces;
55 
56 struct ast_timer {
57  int fd;
59 };
60 
61 static int timing_holder_cmp(void *_h1, void *_h2)
62 {
63  struct timing_holder *h1 = _h1;
64  struct timing_holder *h2 = _h2;
65 
66  if (h1->iface->priority > h2->iface->priority) {
67  return 1;
68  } else if (h1->iface->priority == h2->iface->priority) {
69  return 0;
70  } else {
71  return -1;
72  }
73 }
74 
76  struct ast_module *mod)
77 {
78  struct timing_holder *h;
79 
80  if (!funcs->timer_open ||
81  !funcs->timer_close ||
82  !funcs->timer_set_rate ||
83  !funcs->timer_ack ||
84  !funcs->timer_get_event ||
85  !funcs->timer_get_max_rate ||
86  !funcs->timer_enable_continuous ||
87  !funcs->timer_disable_continuous) {
88  return NULL;
89  }
90 
91  if (!(h = ast_calloc(1, sizeof(*h)))) {
92  return NULL;
93  }
94 
95  h->iface = funcs;
96  h->mod = mod;
97 
98  ast_heap_wrlock(timing_interfaces);
99  ast_heap_push(timing_interfaces, h);
100  ast_heap_unlock(timing_interfaces);
101 
102  return h;
103 }
104 
106 {
107  struct timing_holder *h = handle;
108  int res = -1;
109 
110  ast_heap_wrlock(timing_interfaces);
111  h = ast_heap_remove(timing_interfaces, h);
112  ast_heap_unlock(timing_interfaces);
113 
114  if (h) {
115  ast_free(h);
116  h = NULL;
117  res = 0;
118  }
119 
120  return res;
121 }
122 
124 {
125  int fd = -1;
126  struct timing_holder *h;
127  struct ast_timer *t = NULL;
128 
129  ast_heap_rdlock(timing_interfaces);
130 
131  if ((h = ast_heap_peek(timing_interfaces, 1))) {
132  fd = h->iface->timer_open();
133  ast_module_ref(h->mod);
134  }
135 
136  if (fd != -1) {
137  if (!(t = ast_calloc(1, sizeof(*t)))) {
138  h->iface->timer_close(fd);
139  } else {
140  t->fd = fd;
141  t->holder = h;
142  }
143  }
144 
145  ast_heap_unlock(timing_interfaces);
146 
147  return t;
148 }
149 
150 void ast_timer_close(struct ast_timer *handle)
151 {
152  handle->holder->iface->timer_close(handle->fd);
153  handle->fd = -1;
154  ast_module_unref(handle->holder->mod);
155  ast_free(handle);
156 }
157 
158 int ast_timer_fd(const struct ast_timer *handle)
159 {
160  return handle->fd;
161 }
162 
163 int ast_timer_set_rate(const struct ast_timer *handle, unsigned int rate)
164 {
165  int res = -1;
166 
167  res = handle->holder->iface->timer_set_rate(handle->fd, rate);
168 
169  return res;
170 }
171 
172 int ast_timer_ack(const struct ast_timer *handle, unsigned int quantity)
173 {
174  int res = -1;
175 
176  res = handle->holder->iface->timer_ack(handle->fd, quantity);
177 
178  return res;
179 }
180 
181 int ast_timer_enable_continuous(const struct ast_timer *handle)
182 {
183  int res = -1;
184 
185  res = handle->holder->iface->timer_enable_continuous(handle->fd);
186 
187  return res;
188 }
189 
190 int ast_timer_disable_continuous(const struct ast_timer *handle)
191 {
192  int res = -1;
193 
194  res = handle->holder->iface->timer_disable_continuous(handle->fd);
195 
196  return res;
197 }
198 
200 {
201  enum ast_timer_event res = -1;
202 
203  res = handle->holder->iface->timer_get_event(handle->fd);
204 
205  return res;
206 }
207 
208 unsigned int ast_timer_get_max_rate(const struct ast_timer *handle)
209 {
210  unsigned int res = 0;
211 
212  res = handle->holder->iface->timer_get_max_rate(handle->fd);
213 
214  return res;
215 }
216 
217 const char *ast_timer_get_name(const struct ast_timer *handle)
218 {
219  return handle->holder->iface->name;
220 }
221 
222 static char *timing_test(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
223 {
224  struct ast_timer *timer;
225  int count = 0;
226  struct timeval start, end;
227  unsigned int test_rate = 50;
228 
229  switch (cmd) {
230  case CLI_INIT:
231  e->command = "timing test";
232  e->usage = "Usage: timing test <rate>\n"
233  " Test a timer with a specified rate, 50/sec by default.\n"
234  "";
235  return NULL;
236  case CLI_GENERATE:
237  return NULL;
238  }
239 
240  if (a->argc != 2 && a->argc != 3) {
241  return CLI_SHOWUSAGE;
242  }
243 
244  if (a->argc == 3) {
245  unsigned int rate;
246  if (sscanf(a->argv[2], "%30u", &rate) == 1) {
247  test_rate = rate;
248  } else {
249  ast_cli(a->fd, "Invalid rate '%s', using default of %u\n", a->argv[2], test_rate);
250  }
251  }
252 
253  ast_cli(a->fd, "Attempting to test a timer with %u ticks per second.\n", test_rate);
254 
255  if (!(timer = ast_timer_open())) {
256  ast_cli(a->fd, "Failed to open timing fd\n");
257  return CLI_FAILURE;
258  }
259 
260  ast_cli(a->fd, "Using the '%s' timing module for this test.\n", timer->holder->iface->name);
261 
262  start = ast_tvnow();
263 
264  ast_timer_set_rate(timer, test_rate);
265 
266  while (ast_tvdiff_ms((end = ast_tvnow()), start) < 1000) {
267  int res;
268  struct pollfd pfd = {
269  .fd = ast_timer_fd(timer),
270  .events = POLLIN | POLLPRI,
271  };
272 
273  res = ast_poll(&pfd, 1, 100);
274 
275  if (res == 1) {
276  count++;
277  if (ast_timer_ack(timer, 1) < 0) {
278  ast_cli(a->fd, "Timer failed to acknowledge.\n");
279  ast_timer_close(timer);
280  return CLI_FAILURE;
281  }
282  } else if (!res) {
283  ast_cli(a->fd, "poll() timed out! This is bad.\n");
284  } else if (errno != EAGAIN && errno != EINTR) {
285  ast_cli(a->fd, "poll() returned error: %s\n", strerror(errno));
286  }
287  }
288 
289  ast_timer_close(timer);
290  timer = NULL;
291 
292  ast_cli(a->fd, "It has been %" PRIi64 " milliseconds, and we got %d timer ticks\n",
293  ast_tvdiff_ms(end, start), count);
294 
295  return CLI_SUCCESS;
296 }
297 
298 static struct ast_cli_entry cli_timing[] = {
299  AST_CLI_DEFINE(timing_test, "Run a timing test"),
300 };
301 
302 static void timing_shutdown(void)
303 {
304  ast_cli_unregister_multiple(cli_timing, ARRAY_LEN(cli_timing));
305 
306  ast_heap_destroy(timing_interfaces);
307  timing_interfaces = NULL;
308 }
309 
311 {
312  if (!(timing_interfaces = ast_heap_create(2, timing_holder_cmp, 0))) {
313  return -1;
314  }
315 
317 
318  return ast_cli_register_multiple(cli_timing, ARRAY_LEN(cli_timing));
319 }
const char * name
Definition: timing.h:70
Timing module interface.
Definition: timing.h:69
#define AST_CLI_DEFINE(fn, txt,...)
Definition: cli.h:191
Asterisk locking-related definitions:
unsigned int ast_timer_get_max_rate(const struct ast_timer *handle)
Get maximum rate supported for a timer.
Definition: timing.c:208
Asterisk main include file. File version handling, generic pbx functions.
#define ARRAY_LEN(a)
Definition: isdn_lib.c:42
void ast_module_unref(struct ast_module *)
Definition: loader.c:1312
static void timing_shutdown(void)
Definition: timing.c:302
ssize_t __heap_index
Definition: timing.c:49
struct ast_timing_interface * iface
Definition: timing.c:51
int(* timer_open)(void)
Definition: timing.h:74
int ast_cli_unregister_multiple(struct ast_cli_entry *e, int len)
Unregister multiple commands.
Definition: cli.c:2177
static int timing_holder_cmp(void *_h1, void *_h2)
Definition: timing.c:61
Time-related functions and macros.
int ast_unregister_timing_interface(void *handle)
Unregister a previously registered timing interface.
Definition: timing.c:105
#define ast_heap_unlock(h)
Definition: heap.h:252
descriptor for a cli entry.
Definition: cli.h:165
const int argc
Definition: cli.h:154
ast_timer_event
Definition: timing.h:57
int ast_heap_push(struct ast_heap *h, void *elm)
Push an element on to a heap.
Definition: heap.c:250
int(* timer_enable_continuous)(int handle)
Definition: timing.h:78
Definition: heap.c:38
Definition: cli.h:146
void ast_timer_close(struct ast_timer *handle)
Close an opened timing handle.
Definition: timing.c:150
struct ast_timer * ast_timer_open(void)
Open a timer.
Definition: timing.c:123
struct ast_heap * ast_heap_destroy(struct ast_heap *h)
Destroy a max heap.
Definition: heap.c:163
enum ast_timer_event(* timer_get_event)(int handle)
Definition: timing.h:80
struct timeval ast_tvnow(void)
Returns current timeval. Meant to replace calls to gettimeofday().
Definition: time.h:142
int64_t ast_tvdiff_ms(struct timeval end, struct timeval start)
Computes the difference (in milliseconds) between two struct timeval instances.
Definition: time.h:90
static char * timing_test(struct ast_cli_entry *e, int cmd, struct ast_cli_args *a)
Definition: timing.c:222
void(* timer_close)(int handle)
Definition: timing.h:75
void ast_cli(int fd, const char *fmt,...)
Definition: cli.c:105
int(* timer_disable_continuous)(int handle)
Definition: timing.h:79
Utility functions.
Max Heap data structure.
int(* timer_set_rate)(int handle, unsigned int rate)
Definition: timing.h:76
unsigned int priority
Definition: timing.h:73
const int fd
Definition: cli.h:153
int ast_timer_disable_continuous(const struct ast_timer *handle)
Disable continuous mode.
Definition: timing.c:190
#define ast_poll(a, b, c)
Definition: poll-compat.h:88
int ast_register_atexit(void(*func)(void))
Register a function to be executed before Asterisk exits.
Definition: asterisk.c:998
struct timing_holder * holder
Definition: timing.c:58
const char *const * argv
Definition: cli.h:155
int ast_timer_ack(const struct ast_timer *handle, unsigned int quantity)
Acknowledge a timer event.
Definition: timing.c:172
void * _ast_register_timing_interface(struct ast_timing_interface *funcs, struct ast_module *mod)
Definition: timing.c:75
#define CLI_SHOWUSAGE
Definition: cli.h:44
int(* timer_ack)(int handle, unsigned int quantity)
Definition: timing.h:77
#define ast_heap_rdlock(h)
Definition: heap.h:251
unsigned int(* timer_get_max_rate)(int handle)
Definition: timing.h:81
int fd
Definition: timing.c:57
#define CLI_FAILURE
Definition: cli.h:45
int errno
#define ast_free(a)
Definition: astmm.h:97
char * command
Definition: cli.h:180
static struct ast_heap * timing_interfaces
Definition: timing.c:54
int ast_timer_fd(const struct ast_timer *handle)
Get a poll()-able file descriptor for a timer.
Definition: timing.c:158
int ast_timer_set_rate(const struct ast_timer *handle, unsigned int rate)
Set the timing tick rate.
Definition: timing.c:163
int ast_timer_enable_continuous(const struct ast_timer *handle)
Enable continuous mode.
Definition: timing.c:181
const char * usage
Definition: cli.h:171
#define CLI_SUCCESS
Definition: cli.h:43
void * ast_heap_remove(struct ast_heap *h, void *elm)
Remove a specific element from a heap.
Definition: heap.c:284
Standard Command Line Interface.
#define ast_calloc(a, b)
Definition: astmm.h:82
int ast_cli_register_multiple(struct ast_cli_entry *e, int len)
Register multiple commands.
Definition: cli.c:2167
struct ast_heap * ast_heap_create(unsigned int init_height, ast_heap_cmp_fn cmp_fn, ssize_t index_offset)
Create a max heap.
Definition: heap.c:118
struct ast_module * mod
Definition: timing.c:50
void * ast_heap_peek(struct ast_heap *h, unsigned int index)
Peek at an element on a heap.
Definition: heap.c:300
static struct ast_cli_entry cli_timing[]
Definition: timing.c:298
int ast_timing_init(void)
Definition: timing.c:310
enum ast_timer_event ast_timer_get_event(const struct ast_timer *handle)
Retrieve timing event.
Definition: timing.c:199
const char * ast_timer_get_name(const struct ast_timer *handle)
Get name of timer in use.
Definition: timing.c:217
static struct ast_timer * timer
Definition: chan_iax2.c:313
Asterisk module definitions.
Timing source management.
#define ast_heap_wrlock(h)
Definition: heap.h:250
#define ASTERISK_FILE_VERSION(file, version)
Register/unregister a source code file with the core.
Definition: asterisk.h:180
struct ast_module * ast_module_ref(struct ast_module *)
Definition: loader.c:1300