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"
32 #include "common.h"
33 #include "plugin.h"
34 #include "configfile.h"
36 #include <netdb.h>
37 #include <sys/un.h>
38 #include <netinet/in.h>
39 #include <netinet/tcp.h>
41 #define MEMCACHED_DEF_HOST "127.0.0.1"
42 #define MEMCACHED_DEF_PORT "11211"
44 struct memcached_s
45 {
46 char *name;
47 char *socket;
48 char *host;
49 char *port;
50 };
51 typedef struct memcached_s memcached_t;
53 static _Bool memcached_have_instances = 0;
55 static void memcached_free (void *arg)
56 {
57 memcached_t *st = arg;
58 if (st == NULL)
59 return;
61 sfree (st->name);
62 sfree (st->socket);
63 sfree (st->host);
64 sfree (st->port);
65 sfree (st);
66 }
68 static int memcached_connect_unix (memcached_t *st)
69 {
70 struct sockaddr_un serv_addr = { 0 };
71 int fd;
73 serv_addr.sun_family = AF_UNIX;
74 sstrncpy (serv_addr.sun_path, st->socket,
75 sizeof (serv_addr.sun_path));
77 /* create our socket descriptor */
78 fd = socket (AF_UNIX, SOCK_STREAM, 0);
79 if (fd < 0)
80 {
81 char errbuf[1024];
82 ERROR ("memcached plugin: memcached_connect_unix: socket(2) failed: %s",
83 sstrerror (errno, errbuf, sizeof (errbuf)));
84 return (-1);
85 }
87 /* connect to the memcached daemon */
88 int status = connect (fd, (struct sockaddr *)&serv_addr, sizeof(serv_addr));
89 if (status != 0)
90 {
91 shutdown (fd, SHUT_RDWR);
92 close (fd);
93 fd = -1;
94 }
96 return (fd);
97 } /* int memcached_connect_unix */
99 static int memcached_connect_inet (memcached_t *st)
100 {
101 const char *host;
102 const char *port;
104 struct addrinfo *ai_list, *ai_ptr;
105 int status;
106 int fd = -1;
108 host = (st->host != NULL) ? st->host : MEMCACHED_DEF_HOST;
109 port = (st->port != NULL) ? st->port : MEMCACHED_DEF_PORT;
111 ai_list = NULL;
113 struct addrinfo ai_hints = {
114 .ai_family = AF_UNSPEC,
115 .ai_flags = AI_ADDRCONFIG,
116 .ai_socktype = SOCK_STREAM
117 };
119 status = getaddrinfo (host, port, &ai_hints, &ai_list);
120 if (status != 0)
121 {
122 char errbuf[1024];
123 ERROR ("memcached plugin: memcached_connect_inet: "
124 "getaddrinfo(%s,%s) failed: %s",
125 host, port,
126 (status == EAI_SYSTEM)
127 ? sstrerror (errno, errbuf, sizeof (errbuf))
128 : gai_strerror (status));
129 return (-1);
130 }
132 for (ai_ptr = ai_list; ai_ptr != NULL; ai_ptr = ai_ptr->ai_next)
133 {
134 /* create our socket descriptor */
135 fd = socket (ai_ptr->ai_family, ai_ptr->ai_socktype, ai_ptr->ai_protocol);
136 if (fd < 0)
137 {
138 char errbuf[1024];
139 WARNING ("memcached plugin: memcached_connect_inet: "
140 "socket(2) failed: %s",
141 sstrerror (errno, errbuf, sizeof (errbuf)));
142 continue;
143 }
145 /* connect to the memcached daemon */
146 status = (int) connect (fd, ai_ptr->ai_addr, ai_ptr->ai_addrlen);
147 if (status != 0)
148 {
149 shutdown (fd, SHUT_RDWR);
150 close (fd);
151 fd = -1;
152 continue;
153 }
155 /* A socket could be opened and connecting succeeded. We're done. */
156 break;
157 }
159 freeaddrinfo (ai_list);
160 return (fd);
161 } /* int memcached_connect_inet */
163 static int memcached_connect (memcached_t *st)
164 {
165 if (st->socket != NULL)
166 return (memcached_connect_unix (st));
167 else
168 return (memcached_connect_inet (st));
169 }
171 static int memcached_query_daemon (char *buffer, size_t buffer_size, memcached_t *st)
172 {
173 int fd, status;
174 size_t buffer_fill;
176 fd = memcached_connect (st);
177 if (fd < 0) {
178 ERROR ("memcached plugin: Instance \"%s\" could not connect to daemon.",
179 st->name);
180 return -1;
181 }
183 status = (int) swrite (fd, "stats\r\n", strlen ("stats\r\n"));
184 if (status != 0)
185 {
186 char errbuf[1024];
187 ERROR ("memcached plugin: write(2) failed: %s",
188 sstrerror (errno, errbuf, sizeof (errbuf)));
189 shutdown(fd, SHUT_RDWR);
190 close (fd);
191 return (-1);
192 }
194 /* receive data from the memcached daemon */
195 memset (buffer, 0, buffer_size);
197 buffer_fill = 0;
198 while ((status = (int) recv (fd, buffer + buffer_fill,
199 buffer_size - buffer_fill, /* flags = */ 0)) != 0)
200 {
201 char const end_token[5] = {'E', 'N', 'D', '\r', '\n'};
202 if (status < 0)
203 {
204 char errbuf[1024];
206 if ((errno == EAGAIN) || (errno == EINTR))
207 continue;
209 ERROR ("memcached: Error reading from socket: %s",
210 sstrerror (errno, errbuf, sizeof (errbuf)));
211 shutdown(fd, SHUT_RDWR);
212 close (fd);
213 return (-1);
214 }
216 buffer_fill += (size_t) status;
217 if (buffer_fill > buffer_size)
218 {
219 buffer_fill = buffer_size;
220 WARNING ("memcached plugin: Message was truncated.");
221 break;
222 }
224 /* If buffer ends in end_token, we have all the data. */
225 if (memcmp (buffer + buffer_fill - sizeof (end_token),
226 end_token, sizeof (end_token)) == 0)
227 break;
228 } /* while (recv) */
230 status = 0;
231 if (buffer_fill == 0)
232 {
233 WARNING ("memcached plugin: No data returned by memcached.");
234 status = -1;
235 }
237 shutdown(fd, SHUT_RDWR);
238 close(fd);
239 return (status);
240 } /* int memcached_query_daemon */
242 static void memcached_init_vl (value_list_t *vl, memcached_t const *st)
243 {
244 sstrncpy (vl->plugin, "memcached", sizeof (vl->plugin));
245 if (strcmp (st->name, "__legacy__") == 0) /* legacy mode */
246 {
247 sstrncpy (vl->host, hostname_g, sizeof (vl->host));
248 }
249 else
250 {
251 if (st->socket != NULL)
252 sstrncpy (vl->host, hostname_g, sizeof (vl->host));
253 else
254 sstrncpy (vl->host,
255 (st->host != NULL) ? st->host : MEMCACHED_DEF_HOST,
256 sizeof (vl->host));
257 sstrncpy (vl->plugin_instance, st->name, sizeof (vl->plugin_instance));
258 }
259 }
261 static void submit_derive (const char *type, const char *type_inst,
262 derive_t value, memcached_t *st)
263 {
264 value_t values[1];
265 value_list_t vl = VALUE_LIST_INIT;
266 memcached_init_vl (&vl, st);
268 values[0].derive = value;
270 vl.values = values;
271 vl.values_len = 1;
272 sstrncpy (vl.type, type, sizeof (vl.type));
273 if (type_inst != NULL)
274 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
276 plugin_dispatch_values (&vl);
277 }
279 static void submit_derive2 (const char *type, const char *type_inst,
280 derive_t value0, derive_t value1, memcached_t *st)
281 {
282 value_t values[2];
283 value_list_t vl = VALUE_LIST_INIT;
284 memcached_init_vl (&vl, st);
286 values[0].derive = value0;
287 values[1].derive = value1;
289 vl.values = values;
290 vl.values_len = 2;
291 sstrncpy (vl.type, type, sizeof (vl.type));
292 if (type_inst != NULL)
293 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
295 plugin_dispatch_values (&vl);
296 }
298 static void submit_gauge (const char *type, const char *type_inst,
299 gauge_t value, memcached_t *st)
300 {
301 value_t values[1];
302 value_list_t vl = VALUE_LIST_INIT;
303 memcached_init_vl (&vl, st);
305 values[0].gauge = value;
307 vl.values = values;
308 vl.values_len = 1;
309 sstrncpy (vl.type, type, sizeof (vl.type));
310 if (type_inst != NULL)
311 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
313 plugin_dispatch_values (&vl);
314 }
316 static void submit_gauge2 (const char *type, const char *type_inst,
317 gauge_t value0, gauge_t value1, memcached_t *st)
318 {
319 value_t values[2];
320 value_list_t vl = VALUE_LIST_INIT;
321 memcached_init_vl (&vl, st);
323 values[0].gauge = value0;
324 values[1].gauge = value1;
326 vl.values = values;
327 vl.values_len = 2;
328 sstrncpy (vl.type, type, sizeof (vl.type));
329 if (type_inst != NULL)
330 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
332 plugin_dispatch_values (&vl);
333 }
335 static int memcached_read (user_data_t *user_data)
336 {
337 char buf[4096];
338 char *fields[3];
339 char *ptr;
340 char *line;
341 char *saveptr;
342 int fields_num;
344 gauge_t bytes_used = NAN;
345 gauge_t bytes_total = NAN;
346 gauge_t hits = NAN;
347 gauge_t gets = NAN;
348 gauge_t incr_hits = NAN;
349 derive_t incr = 0;
350 gauge_t decr_hits = NAN;
351 derive_t decr = 0;
352 derive_t rusage_user = 0;
353 derive_t rusage_syst = 0;
354 derive_t octets_rx = 0;
355 derive_t octets_tx = 0;
357 memcached_t *st;
358 st = user_data->data;
360 /* get data from daemon */
361 if (memcached_query_daemon (buf, sizeof (buf), st) < 0) {
362 return -1;
363 }
365 #define FIELD_IS(cnst) \
366 (((sizeof(cnst) - 1) == name_len) && (strcmp (cnst, fields[1]) == 0))
368 ptr = buf;
369 saveptr = NULL;
370 while ((line = strtok_r (ptr, "\n\r", &saveptr)) != NULL)
371 {
372 int name_len;
374 ptr = NULL;
376 fields_num = strsplit(line, fields, 3);
377 if (fields_num != 3)
378 continue;
380 name_len = strlen(fields[1]);
381 if (name_len == 0)
382 continue;
384 /*
385 * For an explanation on these fields please refer to
386 * <https://github.com/memcached/memcached/blob/master/doc/protocol.txt>
387 */
389 /*
390 * CPU time consumed by the memcached process
391 */
392 if (FIELD_IS ("rusage_user"))
393 {
394 rusage_user = atoll (fields[2]);
395 }
396 else if (FIELD_IS ("rusage_system"))
397 {
398 rusage_syst = atoll(fields[2]);
399 }
401 /*
402 * Number of threads of this instance
403 */
404 else if (FIELD_IS ("threads"))
405 {
406 submit_gauge2 ("ps_count", NULL, NAN, atof (fields[2]), st);
407 }
409 /*
410 * Number of items stored
411 */
412 else if (FIELD_IS ("curr_items"))
413 {
414 submit_gauge ("memcached_items", "current", atof (fields[2]), st);
415 }
417 /*
418 * Number of bytes used and available (total - used)
419 */
420 else if (FIELD_IS ("bytes"))
421 {
422 bytes_used = atof (fields[2]);
423 }
424 else if (FIELD_IS ("limit_maxbytes"))
425 {
426 bytes_total = atof(fields[2]);
427 }
429 /*
430 * Connections
431 */
432 else if (FIELD_IS ("curr_connections"))
433 {
434 submit_gauge ("memcached_connections", "current", atof (fields[2]), st);
435 }
436 else if (FIELD_IS ("listen_disabled_num"))
437 {
438 submit_derive ("connections", "listen_disabled", atof (fields[2]), st);
439 }
441 /*
442 * Commands
443 */
444 else if ((name_len > 4) && (strncmp (fields[1], "cmd_", 4) == 0))
445 {
446 const char *name = fields[1] + 4;
447 submit_derive ("memcached_command", name, atoll (fields[2]), st);
448 if (strcmp (name, "get") == 0)
449 gets = atof (fields[2]);
450 }
452 /*
453 * Increment/Decrement
454 */
455 else if (FIELD_IS("incr_misses"))
456 {
457 derive_t incr_count = atoll (fields[2]);
458 submit_derive ("memcached_ops", "incr_misses", incr_count, st);
459 incr += incr_count;
460 }
461 else if (FIELD_IS ("incr_hits"))
462 {
463 derive_t incr_count = atoll (fields[2]);
464 submit_derive ("memcached_ops", "incr_hits", incr_count, st);
465 incr_hits = atof (fields[2]);
466 incr += incr_count;
467 }
468 else if (FIELD_IS ("decr_misses"))
469 {
470 derive_t decr_count = atoll (fields[2]);
471 submit_derive ("memcached_ops", "decr_misses", decr_count, st);
472 decr += decr_count;
473 }
474 else if (FIELD_IS ("decr_hits"))
475 {
476 derive_t decr_count = atoll (fields[2]);
477 submit_derive ("memcached_ops", "decr_hits", decr_count, st);
478 decr_hits = atof (fields[2]);
479 decr += decr_count;
480 }
482 /*
483 * Operations on the cache, i. e. cache hits, cache misses and evictions of items
484 */
485 else if (FIELD_IS ("get_hits"))
486 {
487 submit_derive ("memcached_ops", "hits", atoll (fields[2]), st);
488 hits = atof (fields[2]);
489 }
490 else if (FIELD_IS ("get_misses"))
491 {
492 submit_derive ("memcached_ops", "misses", atoll (fields[2]), st);
493 }
494 else if (FIELD_IS ("evictions"))
495 {
496 submit_derive ("memcached_ops", "evictions", atoll (fields[2]), st);
497 }
499 /*
500 * Network traffic
501 */
502 else if (FIELD_IS ("bytes_read"))
503 {
504 octets_rx = atoll (fields[2]);
505 }
506 else if (FIELD_IS ("bytes_written"))
507 {
508 octets_tx = atoll (fields[2]);
509 }
510 } /* while ((line = strtok_r (ptr, "\n\r", &saveptr)) != NULL) */
512 if (!isnan (bytes_used) && !isnan (bytes_total) && (bytes_used <= bytes_total))
513 submit_gauge2 ("df", "cache", bytes_used, bytes_total - bytes_used, st);
515 if ((rusage_user != 0) || (rusage_syst != 0))
516 submit_derive2 ("ps_cputime", NULL, rusage_user, rusage_syst, st);
518 if ((octets_rx != 0) || (octets_tx != 0))
519 submit_derive2 ("memcached_octets", NULL, octets_rx, octets_tx, st);
521 if (!isnan (gets) && !isnan (hits))
522 {
523 gauge_t rate = NAN;
525 if (gets != 0.0)
526 rate = 100.0 * hits / gets;
528 submit_gauge ("percent", "hitratio", rate, st);
529 }
531 if (!isnan (incr_hits) && incr != 0)
532 {
533 gauge_t incr_rate = 100.0 * incr_hits / incr;
534 submit_gauge ("percent", "incr_hitratio", incr_rate, st);
535 submit_derive ("memcached_ops", "incr", incr, st);
536 }
538 if (!isnan (decr_hits) && decr != 0)
539 {
540 gauge_t decr_rate = 100.0 * decr_hits / decr;
541 submit_gauge ("percent", "decr_hitratio", decr_rate, st);
542 submit_derive ("memcached_ops", "decr", decr, st);
543 }
545 return 0;
546 } /* int memcached_read */
548 static int memcached_add_read_callback (memcached_t *st)
549 {
550 user_data_t ud = { 0 };
551 char callback_name[3*DATA_MAX_NAME_LEN];
552 int status;
554 ud.data = st;
555 ud.free_func = memcached_free;
557 assert (st->name != NULL);
558 ssnprintf (callback_name, sizeof (callback_name), "memcached/%s", st->name);
560 status = plugin_register_complex_read (/* group = */ "memcached",
561 /* name = */ callback_name,
562 /* callback = */ memcached_read,
563 /* interval = */ 0,
564 /* user_data = */ &ud);
565 return (status);
566 } /* int memcached_add_read_callback */
568 /* Configuration handling functiions
569 * <Plugin memcached>
570 * <Instance "instance_name">
571 * Host foo.zomg.com
572 * Port "1234"
573 * </Instance>
574 * </Plugin>
575 */
576 static int config_add_instance(oconfig_item_t *ci)
577 {
578 memcached_t *st;
579 int i;
580 int status = 0;
582 /* Disable automatic generation of default instance in the init callback. */
583 memcached_have_instances = 1;
585 st = calloc (1, sizeof (*st));
586 if (st == NULL)
587 {
588 ERROR ("memcached plugin: calloc failed.");
589 return (-1);
590 }
592 st->name = NULL;
593 st->socket = NULL;
594 st->host = NULL;
595 st->port = NULL;
597 if (strcasecmp (ci->key, "Plugin") == 0) /* default instance */
598 st->name = sstrdup ("__legacy__");
599 else /* <Instance /> block */
600 status = cf_util_get_string (ci, &st->name);
601 if (status != 0)
602 {
603 sfree (st);
604 return (status);
605 }
606 assert (st->name != NULL);
608 for (i = 0; i < ci->children_num; i++)
609 {
610 oconfig_item_t *child = ci->children + i;
612 if (strcasecmp ("Socket", child->key) == 0)
613 status = cf_util_get_string (child, &st->socket);
614 else if (strcasecmp ("Host", child->key) == 0)
615 status = cf_util_get_string (child, &st->host);
616 else if (strcasecmp ("Port", child->key) == 0)
617 status = cf_util_get_service (child, &st->port);
618 else
619 {
620 WARNING ("memcached plugin: Option `%s' not allowed here.",
621 child->key);
622 status = -1;
623 }
625 if (status != 0)
626 break;
627 }
629 if (status == 0)
630 status = memcached_add_read_callback (st);
632 if (status != 0)
633 {
634 memcached_free(st);
635 return (-1);
636 }
638 return (0);
639 }
641 static int memcached_config (oconfig_item_t *ci)
642 {
643 int status = 0;
644 _Bool have_instance_block = 0;
645 int i;
647 for (i = 0; i < ci->children_num; i++)
648 {
649 oconfig_item_t *child = ci->children + i;
651 if (strcasecmp ("Instance", child->key) == 0)
652 {
653 config_add_instance (child);
654 have_instance_block = 1;
655 }
656 else if (!have_instance_block)
657 {
658 /* Non-instance option: Assume legacy configuration (without <Instance />
659 * blocks) and call config_add_instance() with the <Plugin /> block. */
660 return (config_add_instance (ci));
661 }
662 else
663 WARNING ("memcached plugin: The configuration option "
664 "\"%s\" is not allowed here. Did you "
665 "forget to add an <Instance /> block "
666 "around the configuration?",
667 child->key);
668 } /* for (ci->children) */
670 return (status);
671 }
673 static int memcached_init (void)
674 {
675 memcached_t *st;
676 int status;
678 if (memcached_have_instances)
679 return (0);
681 /* No instances were configured, lets start a default instance. */
682 st = calloc (1, sizeof (*st));
683 if (st == NULL)
684 return (ENOMEM);
685 st->name = sstrdup ("__legacy__");
686 st->socket = NULL;
687 st->host = NULL;
688 st->port = NULL;
690 status = memcached_add_read_callback (st);
691 if (status == 0)
692 memcached_have_instances = 1;
693 else
694 memcached_free (st);
696 return (status);
697 } /* int memcached_init */
699 void module_register (void)
700 {
701 plugin_register_complex_config ("memcached", memcached_config);
702 plugin_register_init ("memcached", memcached_init);
703 }