1 /**
2 * collectd - src/memcached.c, based on src/hddtemp.c
3 * Copyright (C) 2007 Antony Dovgal
4 * Copyright (C) 2007-2012 Florian Forster
5 * Copyright (C) 2009 Doug MacEachern
6 * Copyright (C) 2009 Franck Lombardi
7 * Copyright (C) 2012 Nicolas Szalay
8 *
9 * This program is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU General Public License as published by the
11 * Free Software Foundation; either version 2 of the License, or (at your
12 * option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful, but
15 * WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License along
20 * with this program; if not, write to the Free Software Foundation, Inc.,
21 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
22 *
23 * Authors:
24 * Antony Dovgal <tony at daylessday dot org>
25 * Florian octo Forster <octo at collectd.org>
26 * Doug MacEachern <dougm at hyperic.com>
27 * Franck Lombardi
28 * Nicolas Szalay
29 **/
31 #include "collectd.h"
33 #include "common.h"
34 #include "plugin.h"
35 #include "configfile.h"
37 #include <netdb.h>
38 #include <sys/un.h>
39 #include <netinet/in.h>
40 #include <netinet/tcp.h>
42 #define MEMCACHED_DEF_HOST "127.0.0.1"
43 #define MEMCACHED_DEF_PORT "11211"
45 struct memcached_s
46 {
47 char *name;
48 char *socket;
49 char *host;
50 char *port;
51 };
52 typedef struct memcached_s memcached_t;
54 static _Bool memcached_have_instances = 0;
56 static void memcached_free (void *arg)
57 {
58 memcached_t *st = arg;
59 if (st == NULL)
60 return;
62 sfree (st->name);
63 sfree (st->socket);
64 sfree (st->host);
65 sfree (st->port);
66 sfree (st);
67 }
69 static int memcached_connect_unix (memcached_t *st)
70 {
71 struct sockaddr_un serv_addr = { 0 };
72 int fd;
74 serv_addr.sun_family = AF_UNIX;
75 sstrncpy (serv_addr.sun_path, st->socket,
76 sizeof (serv_addr.sun_path));
78 /* create our socket descriptor */
79 fd = socket (AF_UNIX, SOCK_STREAM, 0);
80 if (fd < 0)
81 {
82 char errbuf[1024];
83 ERROR ("memcached plugin: memcached_connect_unix: socket(2) failed: %s",
84 sstrerror (errno, errbuf, sizeof (errbuf)));
85 return (-1);
86 }
88 /* connect to the memcached daemon */
89 int status = connect (fd, (struct sockaddr *)&serv_addr, sizeof(serv_addr));
90 if (status != 0)
91 {
92 shutdown (fd, SHUT_RDWR);
93 close (fd);
94 fd = -1;
95 }
97 return (fd);
98 } /* int memcached_connect_unix */
100 static int memcached_connect_inet (memcached_t *st)
101 {
102 const char *host;
103 const char *port;
105 struct addrinfo *ai_list, *ai_ptr;
106 int status;
107 int fd = -1;
109 host = (st->host != NULL) ? st->host : MEMCACHED_DEF_HOST;
110 port = (st->port != NULL) ? st->port : MEMCACHED_DEF_PORT;
112 struct addrinfo ai_hints = {
113 .ai_family = AF_UNSPEC,
114 .ai_flags = AI_ADDRCONFIG,
115 .ai_socktype = SOCK_STREAM
116 };
118 status = getaddrinfo (host, port, &ai_hints, &ai_list);
119 if (status != 0)
120 {
121 char errbuf[1024];
122 ERROR ("memcached plugin: memcached_connect_inet: "
123 "getaddrinfo(%s,%s) failed: %s",
124 host, port,
125 (status == EAI_SYSTEM)
126 ? sstrerror (errno, errbuf, sizeof (errbuf))
127 : gai_strerror (status));
128 return (-1);
129 }
131 for (ai_ptr = ai_list; ai_ptr != NULL; ai_ptr = ai_ptr->ai_next)
132 {
133 /* create our socket descriptor */
134 fd = socket (ai_ptr->ai_family, ai_ptr->ai_socktype, ai_ptr->ai_protocol);
135 if (fd < 0)
136 {
137 char errbuf[1024];
138 WARNING ("memcached plugin: memcached_connect_inet: "
139 "socket(2) failed: %s",
140 sstrerror (errno, errbuf, sizeof (errbuf)));
141 continue;
142 }
144 /* connect to the memcached daemon */
145 status = (int) connect (fd, ai_ptr->ai_addr, ai_ptr->ai_addrlen);
146 if (status != 0)
147 {
148 shutdown (fd, SHUT_RDWR);
149 close (fd);
150 fd = -1;
151 continue;
152 }
154 /* A socket could be opened and connecting succeeded. We're done. */
155 break;
156 }
158 freeaddrinfo (ai_list);
159 return (fd);
160 } /* int memcached_connect_inet */
162 static int memcached_connect (memcached_t *st)
163 {
164 if (st->socket != NULL)
165 return (memcached_connect_unix (st));
166 else
167 return (memcached_connect_inet (st));
168 }
170 static int memcached_query_daemon (char *buffer, size_t buffer_size, memcached_t *st)
171 {
172 int fd, status;
173 size_t buffer_fill;
175 fd = memcached_connect (st);
176 if (fd < 0) {
177 ERROR ("memcached plugin: Instance \"%s\" could not connect to daemon.",
178 st->name);
179 return -1;
180 }
182 status = (int) swrite (fd, "stats\r\n", strlen ("stats\r\n"));
183 if (status != 0)
184 {
185 char errbuf[1024];
186 ERROR ("memcached plugin: write(2) failed: %s",
187 sstrerror (errno, errbuf, sizeof (errbuf)));
188 shutdown(fd, SHUT_RDWR);
189 close (fd);
190 return (-1);
191 }
193 /* receive data from the memcached daemon */
194 memset (buffer, 0, buffer_size);
196 buffer_fill = 0;
197 while ((status = (int) recv (fd, buffer + buffer_fill,
198 buffer_size - buffer_fill, /* flags = */ 0)) != 0)
199 {
200 char const end_token[5] = {'E', 'N', 'D', '\r', '\n'};
201 if (status < 0)
202 {
203 char errbuf[1024];
205 if ((errno == EAGAIN) || (errno == EINTR))
206 continue;
208 ERROR ("memcached: Error reading from socket: %s",
209 sstrerror (errno, errbuf, sizeof (errbuf)));
210 shutdown(fd, SHUT_RDWR);
211 close (fd);
212 return (-1);
213 }
215 buffer_fill += (size_t) status;
216 if (buffer_fill > buffer_size)
217 {
218 buffer_fill = buffer_size;
219 WARNING ("memcached plugin: Message was truncated.");
220 break;
221 }
223 /* If buffer ends in end_token, we have all the data. */
224 if (memcmp (buffer + buffer_fill - sizeof (end_token),
225 end_token, sizeof (end_token)) == 0)
226 break;
227 } /* while (recv) */
229 status = 0;
230 if (buffer_fill == 0)
231 {
232 WARNING ("memcached plugin: No data returned by memcached.");
233 status = -1;
234 }
236 shutdown(fd, SHUT_RDWR);
237 close(fd);
238 return (status);
239 } /* int memcached_query_daemon */
241 static void memcached_init_vl (value_list_t *vl, memcached_t const *st)
242 {
243 sstrncpy (vl->plugin, "memcached", sizeof (vl->plugin));
244 if (strcmp (st->name, "__legacy__") == 0) /* legacy mode */
245 {
246 sstrncpy (vl->host, hostname_g, sizeof (vl->host));
247 }
248 else
249 {
250 if (st->socket != NULL)
251 sstrncpy (vl->host, hostname_g, sizeof (vl->host));
252 else
253 sstrncpy (vl->host,
254 (st->host != NULL) ? st->host : MEMCACHED_DEF_HOST,
255 sizeof (vl->host));
256 sstrncpy (vl->plugin_instance, st->name, sizeof (vl->plugin_instance));
257 }
258 }
260 static void submit_derive (const char *type, const char *type_inst,
261 derive_t value, memcached_t *st)
262 {
263 value_t values[1];
264 value_list_t vl = VALUE_LIST_INIT;
265 memcached_init_vl (&vl, st);
267 values[0].derive = value;
269 vl.values = values;
270 vl.values_len = 1;
271 sstrncpy (vl.type, type, sizeof (vl.type));
272 if (type_inst != NULL)
273 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
275 plugin_dispatch_values (&vl);
276 }
278 static void submit_derive2 (const char *type, const char *type_inst,
279 derive_t value0, derive_t value1, memcached_t *st)
280 {
281 value_t values[2];
282 value_list_t vl = VALUE_LIST_INIT;
283 memcached_init_vl (&vl, st);
285 values[0].derive = value0;
286 values[1].derive = value1;
288 vl.values = values;
289 vl.values_len = 2;
290 sstrncpy (vl.type, type, sizeof (vl.type));
291 if (type_inst != NULL)
292 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
294 plugin_dispatch_values (&vl);
295 }
297 static void submit_gauge (const char *type, const char *type_inst,
298 gauge_t value, memcached_t *st)
299 {
300 value_t values[1];
301 value_list_t vl = VALUE_LIST_INIT;
302 memcached_init_vl (&vl, st);
304 values[0].gauge = value;
306 vl.values = values;
307 vl.values_len = 1;
308 sstrncpy (vl.type, type, sizeof (vl.type));
309 if (type_inst != NULL)
310 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
312 plugin_dispatch_values (&vl);
313 }
315 static void submit_gauge2 (const char *type, const char *type_inst,
316 gauge_t value0, gauge_t value1, memcached_t *st)
317 {
318 value_t values[2];
319 value_list_t vl = VALUE_LIST_INIT;
320 memcached_init_vl (&vl, st);
322 values[0].gauge = value0;
323 values[1].gauge = value1;
325 vl.values = values;
326 vl.values_len = 2;
327 sstrncpy (vl.type, type, sizeof (vl.type));
328 if (type_inst != NULL)
329 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
331 plugin_dispatch_values (&vl);
332 }
334 static int memcached_read (user_data_t *user_data)
335 {
336 char buf[4096];
337 char *fields[3];
338 char *ptr;
339 char *line;
340 char *saveptr;
341 int fields_num;
343 gauge_t bytes_used = NAN;
344 gauge_t bytes_total = NAN;
345 gauge_t hits = NAN;
346 gauge_t gets = NAN;
347 gauge_t incr_hits = NAN;
348 derive_t incr = 0;
349 gauge_t decr_hits = NAN;
350 derive_t decr = 0;
351 derive_t rusage_user = 0;
352 derive_t rusage_syst = 0;
353 derive_t octets_rx = 0;
354 derive_t octets_tx = 0;
356 memcached_t *st;
357 st = user_data->data;
359 /* get data from daemon */
360 if (memcached_query_daemon (buf, sizeof (buf), st) < 0) {
361 return -1;
362 }
364 #define FIELD_IS(cnst) \
365 (((sizeof(cnst) - 1) == name_len) && (strcmp (cnst, fields[1]) == 0))
367 ptr = buf;
368 saveptr = NULL;
369 while ((line = strtok_r (ptr, "\n\r", &saveptr)) != NULL)
370 {
371 int name_len;
373 ptr = NULL;
375 fields_num = strsplit(line, fields, 3);
376 if (fields_num != 3)
377 continue;
379 name_len = strlen(fields[1]);
380 if (name_len == 0)
381 continue;
383 /*
384 * For an explanation on these fields please refer to
385 * <https://github.com/memcached/memcached/blob/master/doc/protocol.txt>
386 */
388 /*
389 * CPU time consumed by the memcached process
390 */
391 if (FIELD_IS ("rusage_user"))
392 {
393 rusage_user = atoll (fields[2]);
394 }
395 else if (FIELD_IS ("rusage_system"))
396 {
397 rusage_syst = atoll(fields[2]);
398 }
400 /*
401 * Number of threads of this instance
402 */
403 else if (FIELD_IS ("threads"))
404 {
405 submit_gauge2 ("ps_count", NULL, NAN, atof (fields[2]), st);
406 }
408 /*
409 * Number of items stored
410 */
411 else if (FIELD_IS ("curr_items"))
412 {
413 submit_gauge ("memcached_items", "current", atof (fields[2]), st);
414 }
416 /*
417 * Number of bytes used and available (total - used)
418 */
419 else if (FIELD_IS ("bytes"))
420 {
421 bytes_used = atof (fields[2]);
422 }
423 else if (FIELD_IS ("limit_maxbytes"))
424 {
425 bytes_total = atof(fields[2]);
426 }
428 /*
429 * Connections
430 */
431 else if (FIELD_IS ("curr_connections"))
432 {
433 submit_gauge ("memcached_connections", "current", atof (fields[2]), st);
434 }
435 else if (FIELD_IS ("listen_disabled_num"))
436 {
437 submit_derive ("connections", "listen_disabled", atof (fields[2]), st);
438 }
440 /*
441 * Commands
442 */
443 else if ((name_len > 4) && (strncmp (fields[1], "cmd_", 4) == 0))
444 {
445 const char *name = fields[1] + 4;
446 submit_derive ("memcached_command", name, atoll (fields[2]), st);
447 if (strcmp (name, "get") == 0)
448 gets = atof (fields[2]);
449 }
451 /*
452 * Increment/Decrement
453 */
454 else if (FIELD_IS("incr_misses"))
455 {
456 derive_t incr_count = atoll (fields[2]);
457 submit_derive ("memcached_ops", "incr_misses", incr_count, st);
458 incr += incr_count;
459 }
460 else if (FIELD_IS ("incr_hits"))
461 {
462 derive_t incr_count = atoll (fields[2]);
463 submit_derive ("memcached_ops", "incr_hits", incr_count, st);
464 incr_hits = atof (fields[2]);
465 incr += incr_count;
466 }
467 else if (FIELD_IS ("decr_misses"))
468 {
469 derive_t decr_count = atoll (fields[2]);
470 submit_derive ("memcached_ops", "decr_misses", decr_count, st);
471 decr += decr_count;
472 }
473 else if (FIELD_IS ("decr_hits"))
474 {
475 derive_t decr_count = atoll (fields[2]);
476 submit_derive ("memcached_ops", "decr_hits", decr_count, st);
477 decr_hits = atof (fields[2]);
478 decr += decr_count;
479 }
481 /*
482 * Operations on the cache, i. e. cache hits, cache misses and evictions of items
483 */
484 else if (FIELD_IS ("get_hits"))
485 {
486 submit_derive ("memcached_ops", "hits", atoll (fields[2]), st);
487 hits = atof (fields[2]);
488 }
489 else if (FIELD_IS ("get_misses"))
490 {
491 submit_derive ("memcached_ops", "misses", atoll (fields[2]), st);
492 }
493 else if (FIELD_IS ("evictions"))
494 {
495 submit_derive ("memcached_ops", "evictions", atoll (fields[2]), st);
496 }
498 /*
499 * Network traffic
500 */
501 else if (FIELD_IS ("bytes_read"))
502 {
503 octets_rx = atoll (fields[2]);
504 }
505 else if (FIELD_IS ("bytes_written"))
506 {
507 octets_tx = atoll (fields[2]);
508 }
509 } /* while ((line = strtok_r (ptr, "\n\r", &saveptr)) != NULL) */
511 if (!isnan (bytes_used) && !isnan (bytes_total) && (bytes_used <= bytes_total))
512 submit_gauge2 ("df", "cache", bytes_used, bytes_total - bytes_used, st);
514 if ((rusage_user != 0) || (rusage_syst != 0))
515 submit_derive2 ("ps_cputime", NULL, rusage_user, rusage_syst, st);
517 if ((octets_rx != 0) || (octets_tx != 0))
518 submit_derive2 ("memcached_octets", NULL, octets_rx, octets_tx, st);
520 if (!isnan (gets) && !isnan (hits))
521 {
522 gauge_t rate = NAN;
524 if (gets != 0.0)
525 rate = 100.0 * hits / gets;
527 submit_gauge ("percent", "hitratio", rate, st);
528 }
530 if (!isnan (incr_hits) && incr != 0)
531 {
532 gauge_t incr_rate = 100.0 * incr_hits / incr;
533 submit_gauge ("percent", "incr_hitratio", incr_rate, st);
534 submit_derive ("memcached_ops", "incr", incr, st);
535 }
537 if (!isnan (decr_hits) && decr != 0)
538 {
539 gauge_t decr_rate = 100.0 * decr_hits / decr;
540 submit_gauge ("percent", "decr_hitratio", decr_rate, st);
541 submit_derive ("memcached_ops", "decr", decr, st);
542 }
544 return 0;
545 } /* int memcached_read */
547 static int memcached_add_read_callback (memcached_t *st)
548 {
549 user_data_t ud = { 0 };
550 char callback_name[3*DATA_MAX_NAME_LEN];
551 int status;
553 ud.data = st;
554 ud.free_func = memcached_free;
556 assert (st->name != NULL);
557 ssnprintf (callback_name, sizeof (callback_name), "memcached/%s", st->name);
559 status = plugin_register_complex_read (/* group = */ "memcached",
560 /* name = */ callback_name,
561 /* callback = */ memcached_read,
562 /* interval = */ 0,
563 /* user_data = */ &ud);
564 return (status);
565 } /* int memcached_add_read_callback */
567 /* Configuration handling functiions
568 * <Plugin memcached>
569 * <Instance "instance_name">
570 * Host foo.zomg.com
571 * Port "1234"
572 * </Instance>
573 * </Plugin>
574 */
575 static int config_add_instance(oconfig_item_t *ci)
576 {
577 memcached_t *st;
578 int i;
579 int status = 0;
581 /* Disable automatic generation of default instance in the init callback. */
582 memcached_have_instances = 1;
584 st = calloc (1, sizeof (*st));
585 if (st == NULL)
586 {
587 ERROR ("memcached plugin: calloc failed.");
588 return (-1);
589 }
591 st->name = NULL;
592 st->socket = NULL;
593 st->host = NULL;
594 st->port = NULL;
596 if (strcasecmp (ci->key, "Plugin") == 0) /* default instance */
597 st->name = sstrdup ("__legacy__");
598 else /* <Instance /> block */
599 status = cf_util_get_string (ci, &st->name);
600 if (status != 0)
601 {
602 sfree (st);
603 return (status);
604 }
605 assert (st->name != NULL);
607 for (i = 0; i < ci->children_num; i++)
608 {
609 oconfig_item_t *child = ci->children + i;
611 if (strcasecmp ("Socket", child->key) == 0)
612 status = cf_util_get_string (child, &st->socket);
613 else if (strcasecmp ("Host", child->key) == 0)
614 status = cf_util_get_string (child, &st->host);
615 else if (strcasecmp ("Port", child->key) == 0)
616 status = cf_util_get_service (child, &st->port);
617 else
618 {
619 WARNING ("memcached plugin: Option `%s' not allowed here.",
620 child->key);
621 status = -1;
622 }
624 if (status != 0)
625 break;
626 }
628 if (status == 0)
629 status = memcached_add_read_callback (st);
631 if (status != 0)
632 {
633 memcached_free(st);
634 return (-1);
635 }
637 return (0);
638 }
640 static int memcached_config (oconfig_item_t *ci)
641 {
642 int status = 0;
643 _Bool have_instance_block = 0;
644 int i;
646 for (i = 0; i < ci->children_num; i++)
647 {
648 oconfig_item_t *child = ci->children + i;
650 if (strcasecmp ("Instance", child->key) == 0)
651 {
652 config_add_instance (child);
653 have_instance_block = 1;
654 }
655 else if (!have_instance_block)
656 {
657 /* Non-instance option: Assume legacy configuration (without <Instance />
658 * blocks) and call config_add_instance() with the <Plugin /> block. */
659 return (config_add_instance (ci));
660 }
661 else
662 WARNING ("memcached plugin: The configuration option "
663 "\"%s\" is not allowed here. Did you "
664 "forget to add an <Instance /> block "
665 "around the configuration?",
666 child->key);
667 } /* for (ci->children) */
669 return (status);
670 }
672 static int memcached_init (void)
673 {
674 memcached_t *st;
675 int status;
677 if (memcached_have_instances)
678 return (0);
680 /* No instances were configured, lets start a default instance. */
681 st = calloc (1, sizeof (*st));
682 if (st == NULL)
683 return (ENOMEM);
684 st->name = sstrdup ("__legacy__");
685 st->socket = NULL;
686 st->host = NULL;
687 st->port = NULL;
689 status = memcached_add_read_callback (st);
690 if (status == 0)
691 memcached_have_instances = 1;
692 else
693 memcached_free (st);
695 return (status);
696 } /* int memcached_init */
698 void module_register (void)
699 {
700 plugin_register_complex_config ("memcached", memcached_config);
701 plugin_register_init ("memcached", memcached_init);
702 }