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/socket.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 (memcached_t *st)
57 {
58 if (st == NULL)
59 return;
61 sfree (st->name);
62 sfree (st->socket);
63 sfree (st->host);
64 sfree (st->port);
65 }
67 static int memcached_connect_unix (memcached_t *st)
68 {
69 struct sockaddr_un serv_addr;
70 int fd;
72 memset (&serv_addr, 0, sizeof (serv_addr));
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 char *host;
102 char *port;
104 struct addrinfo ai_hints;
105 struct addrinfo *ai_list, *ai_ptr;
106 int status;
107 int fd = -1;
109 memset (&ai_hints, 0, sizeof (ai_hints));
110 ai_hints.ai_flags = 0;
111 #ifdef AI_ADDRCONFIG
112 ai_hints.ai_flags |= AI_ADDRCONFIG;
113 #endif
114 ai_hints.ai_family = AF_UNSPEC;
115 ai_hints.ai_socktype = SOCK_STREAM;
116 ai_hints.ai_protocol = 0;
118 host = (st->host != NULL) ? st->host : MEMCACHED_DEF_HOST;
119 port = (st->port != NULL) ? st->port : MEMCACHED_DEF_PORT;
121 ai_list = NULL;
122 status = getaddrinfo (host, port, &ai_hints, &ai_list);
123 if (status != 0)
124 {
125 char errbuf[1024];
126 ERROR ("memcached plugin: memcached_connect_inet: "
127 "getaddrinfo(%s,%s) failed: %s",
128 host, port,
129 (status == EAI_SYSTEM)
130 ? sstrerror (errno, errbuf, sizeof (errbuf))
131 : gai_strerror (status));
132 return (-1);
133 }
135 for (ai_ptr = ai_list; ai_ptr != NULL; ai_ptr = ai_ptr->ai_next)
136 {
137 /* create our socket descriptor */
138 fd = socket (ai_ptr->ai_family, ai_ptr->ai_socktype, ai_ptr->ai_protocol);
139 if (fd < 0)
140 {
141 char errbuf[1024];
142 WARNING ("memcached plugin: memcached_connect_inet: "
143 "socket(2) failed: %s",
144 sstrerror (errno, errbuf, sizeof (errbuf)));
145 continue;
146 }
148 /* connect to the memcached daemon */
149 status = (int) connect (fd, ai_ptr->ai_addr, ai_ptr->ai_addrlen);
150 if (status != 0)
151 {
152 shutdown (fd, SHUT_RDWR);
153 close (fd);
154 fd = -1;
155 continue;
156 }
158 /* A socket could be opened and connecting succeeded. We're done. */
159 break;
160 }
162 freeaddrinfo (ai_list);
163 return (fd);
164 } /* int memcached_connect_inet */
166 static int memcached_connect (memcached_t *st)
167 {
168 if (st->socket != NULL)
169 return (memcached_connect_unix (st));
170 else
171 return (memcached_connect_inet (st));
172 }
174 static int memcached_query_daemon (char *buffer, size_t buffer_size, memcached_t *st)
175 {
176 int fd = -1;
177 int status;
178 size_t buffer_fill;
180 fd = memcached_connect (st);
181 if (fd < 0) {
182 ERROR ("memcached plugin: Instance \"%s\" could not connect to daemon.",
183 st->name);
184 return -1;
185 }
187 status = (int) swrite (fd, "stats\r\n", strlen ("stats\r\n"));
188 if (status != 0)
189 {
190 char errbuf[1024];
191 ERROR ("memcached plugin: write(2) failed: %s",
192 sstrerror (errno, errbuf, sizeof (errbuf)));
193 shutdown(fd, SHUT_RDWR);
194 close (fd);
195 return (-1);
196 }
198 /* receive data from the memcached daemon */
199 memset (buffer, 0, buffer_size);
201 buffer_fill = 0;
202 while ((status = (int) recv (fd, buffer + buffer_fill,
203 buffer_size - buffer_fill, /* flags = */ 0)) != 0)
204 {
205 char const end_token[5] = {'E', 'N', 'D', '\r', '\n'};
206 if (status < 0)
207 {
208 char errbuf[1024];
210 if ((errno == EAGAIN) || (errno == EINTR))
211 continue;
213 ERROR ("memcached: Error reading from socket: %s",
214 sstrerror (errno, errbuf, sizeof (errbuf)));
215 shutdown(fd, SHUT_RDWR);
216 close (fd);
217 return (-1);
218 }
220 buffer_fill += (size_t) status;
221 if (buffer_fill > buffer_size)
222 {
223 buffer_fill = buffer_size;
224 WARNING ("memcached plugin: Message was truncated.");
225 break;
226 }
228 /* If buffer ends in end_token, we have all the data. */
229 if (memcmp (buffer + buffer_fill - sizeof (end_token),
230 end_token, sizeof (end_token)) == 0)
231 break;
232 } /* while (recv) */
234 status = 0;
235 if (buffer_fill == 0)
236 {
237 WARNING ("memcached plugin: No data returned by memcached.");
238 status = -1;
239 }
241 shutdown(fd, SHUT_RDWR);
242 close(fd);
243 return (status);
244 } /* int memcached_query_daemon */
246 static void memcached_init_vl (value_list_t *vl, memcached_t const *st)
247 {
248 sstrncpy (vl->plugin, "memcached", sizeof (vl->plugin));
249 if (strcmp (st->name, "__legacy__") == 0) /* legacy mode */
250 {
251 sstrncpy (vl->host, hostname_g, sizeof (vl->host));
252 }
253 else
254 {
255 if (st->socket != NULL)
256 sstrncpy (vl->host, hostname_g, sizeof (vl->host));
257 else
258 sstrncpy (vl->host,
259 (st->host != NULL) ? st->host : MEMCACHED_DEF_HOST,
260 sizeof (vl->host));
261 sstrncpy (vl->plugin_instance, st->name, sizeof (vl->plugin_instance));
262 }
263 }
265 static void submit_derive (const char *type, const char *type_inst,
266 derive_t value, memcached_t *st)
267 {
268 value_t values[1];
269 value_list_t vl = VALUE_LIST_INIT;
270 memcached_init_vl (&vl, st);
272 values[0].derive = value;
274 vl.values = values;
275 vl.values_len = 1;
276 sstrncpy (vl.type, type, sizeof (vl.type));
277 if (type_inst != NULL)
278 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
280 plugin_dispatch_values (&vl);
281 }
283 static void submit_derive2 (const char *type, const char *type_inst,
284 derive_t value0, derive_t value1, memcached_t *st)
285 {
286 value_t values[2];
287 value_list_t vl = VALUE_LIST_INIT;
288 memcached_init_vl (&vl, st);
290 values[0].derive = value0;
291 values[1].derive = value1;
293 vl.values = values;
294 vl.values_len = 2;
295 sstrncpy (vl.type, type, sizeof (vl.type));
296 if (type_inst != NULL)
297 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
299 plugin_dispatch_values (&vl);
300 }
302 static void submit_gauge (const char *type, const char *type_inst,
303 gauge_t value, memcached_t *st)
304 {
305 value_t values[1];
306 value_list_t vl = VALUE_LIST_INIT;
307 memcached_init_vl (&vl, st);
309 values[0].gauge = value;
311 vl.values = values;
312 vl.values_len = 1;
313 sstrncpy (vl.type, type, sizeof (vl.type));
314 if (type_inst != NULL)
315 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
317 plugin_dispatch_values (&vl);
318 }
320 static void submit_gauge2 (const char *type, const char *type_inst,
321 gauge_t value0, gauge_t value1, memcached_t *st)
322 {
323 value_t values[2];
324 value_list_t vl = VALUE_LIST_INIT;
325 memcached_init_vl (&vl, st);
327 values[0].gauge = value0;
328 values[1].gauge = value1;
330 vl.values = values;
331 vl.values_len = 2;
332 sstrncpy (vl.type, type, sizeof (vl.type));
333 if (type_inst != NULL)
334 sstrncpy (vl.type_instance, type_inst, sizeof (vl.type_instance));
336 plugin_dispatch_values (&vl);
337 }
339 static int memcached_read (user_data_t *user_data)
340 {
341 char buf[4096];
342 char *fields[3];
343 char *ptr;
344 char *line;
345 char *saveptr;
346 int fields_num;
348 gauge_t bytes_used = NAN;
349 gauge_t bytes_total = NAN;
350 gauge_t hits = NAN;
351 gauge_t gets = NAN;
352 gauge_t incr_hits = NAN;
353 derive_t incr = 0;
354 gauge_t decr_hits = NAN;
355 derive_t decr = 0;
356 derive_t rusage_user = 0;
357 derive_t rusage_syst = 0;
358 derive_t octets_rx = 0;
359 derive_t octets_tx = 0;
361 memcached_t *st;
362 st = user_data->data;
364 /* get data from daemon */
365 if (memcached_query_daemon (buf, sizeof (buf), st) < 0) {
366 return -1;
367 }
369 #define FIELD_IS(cnst) \
370 (((sizeof(cnst) - 1) == name_len) && (strcmp (cnst, fields[1]) == 0))
372 ptr = buf;
373 saveptr = NULL;
374 while ((line = strtok_r (ptr, "\n\r", &saveptr)) != NULL)
375 {
376 int name_len;
378 ptr = NULL;
380 fields_num = strsplit(line, fields, 3);
381 if (fields_num != 3)
382 continue;
384 name_len = strlen(fields[1]);
385 if (name_len == 0)
386 continue;
388 /*
389 * For an explanation on these fields please refer to
390 * <http://code.sixapart.com/svn/memcached/trunk/server/doc/protocol.txt>
391 */
393 /*
394 * CPU time consumed by the memcached process
395 */
396 if (FIELD_IS ("rusage_user"))
397 {
398 rusage_user = atoll (fields[2]);
399 }
400 else if (FIELD_IS ("rusage_system"))
401 {
402 rusage_syst = atoll(fields[2]);
403 }
405 /*
406 * Number of threads of this instance
407 */
408 else if (FIELD_IS ("threads"))
409 {
410 submit_gauge2 ("ps_count", NULL, NAN, atof (fields[2]), st);
411 }
413 /*
414 * Number of items stored
415 */
416 else if (FIELD_IS ("curr_items"))
417 {
418 submit_gauge ("memcached_items", "current", atof (fields[2]), st);
419 }
421 /*
422 * Number of bytes used and available (total - used)
423 */
424 else if (FIELD_IS ("bytes"))
425 {
426 bytes_used = atof (fields[2]);
427 }
428 else if (FIELD_IS ("limit_maxbytes"))
429 {
430 bytes_total = atof(fields[2]);
431 }
433 /*
434 * Connections
435 */
436 else if (FIELD_IS ("curr_connections"))
437 {
438 submit_gauge ("memcached_connections", "current", 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;
551 char callback_name[3*DATA_MAX_NAME_LEN];
552 int status;
554 memset (&ud, 0, sizeof (ud));
555 ud.data = st;
556 ud.free_func = (void *) memcached_free;
558 assert (st->name != NULL);
559 ssnprintf (callback_name, sizeof (callback_name), "memcached/%s", st->name);
561 status = plugin_register_complex_read (/* group = */ "memcached",
562 /* name = */ callback_name,
563 /* callback = */ memcached_read,
564 /* interval = */ NULL,
565 /* user_data = */ &ud);
566 return (status);
567 } /* int memcached_add_read_callback */
569 /* Configuration handling functiions
570 * <Plugin memcached>
571 * <Instance "instance_name">
572 * Host foo.zomg.com
573 * Port "1234"
574 * </Instance>
575 * </Plugin>
576 */
577 static int config_add_instance(oconfig_item_t *ci)
578 {
579 memcached_t *st;
580 int i;
581 int status = 0;
583 /* Disable automatic generation of default instance in the init callback. */
584 memcached_have_instances = 1;
586 st = malloc (sizeof (*st));
587 if (st == NULL)
588 {
589 ERROR ("memcached plugin: malloc failed.");
590 return (-1);
591 }
593 memset (st, 0, sizeof (*st));
594 st->name = NULL;
595 st->socket = NULL;
596 st->host = NULL;
597 st->port = NULL;
599 if (strcasecmp (ci->key, "Plugin") == 0) /* default instance */
600 st->name = sstrdup ("__legacy__");
601 else /* <Instance /> block */
602 status = cf_util_get_string (ci, &st->name);
603 if (status != 0)
604 {
605 sfree (st);
606 return (status);
607 }
608 assert (st->name != NULL);
610 for (i = 0; i < ci->children_num; i++)
611 {
612 oconfig_item_t *child = ci->children + i;
614 if (strcasecmp ("Socket", child->key) == 0)
615 status = cf_util_get_string (child, &st->socket);
616 else if (strcasecmp ("Host", child->key) == 0)
617 status = cf_util_get_string (child, &st->host);
618 else if (strcasecmp ("Port", child->key) == 0)
619 status = cf_util_get_service (child, &st->port);
620 else
621 {
622 WARNING ("memcached plugin: Option `%s' not allowed here.",
623 child->key);
624 status = -1;
625 }
627 if (status != 0)
628 break;
629 }
631 if (status == 0)
632 status = memcached_add_read_callback (st);
634 if (status != 0)
635 {
636 memcached_free(st);
637 return (-1);
638 }
640 return (0);
641 }
643 static int memcached_config (oconfig_item_t *ci)
644 {
645 int status = 0;
646 _Bool have_instance_block = 0;
647 int i;
649 for (i = 0; i < ci->children_num; i++)
650 {
651 oconfig_item_t *child = ci->children + i;
653 if (strcasecmp ("Instance", child->key) == 0)
654 {
655 config_add_instance (child);
656 have_instance_block = 1;
657 }
658 else if (!have_instance_block)
659 {
660 /* Non-instance option: Assume legacy configuration (without <Instance />
661 * blocks) and call config_add_instance() with the <Plugin /> block. */
662 return (config_add_instance (ci));
663 }
664 else
665 WARNING ("memcached plugin: The configuration option "
666 "\"%s\" is not allowed here. Did you "
667 "forget to add an <Instance /> block "
668 "around the configuration?",
669 child->key);
670 } /* for (ci->children) */
672 return (status);
673 }
675 static int memcached_init (void)
676 {
677 memcached_t *st;
678 int status;
680 if (memcached_have_instances)
681 return (0);
683 /* No instances were configured, lets start a default instance. */
684 st = malloc (sizeof (*st));
685 if (st == NULL)
686 return (ENOMEM);
687 memset (st, 0, sizeof (*st));
688 st->name = sstrdup ("__legacy__");
689 st->socket = NULL;
690 st->host = NULL;
691 st->port = NULL;
693 status = memcached_add_read_callback (st);
694 if (status == 0)
695 memcached_have_instances = 1;
696 else
697 memcached_free (st);
699 return (status);
700 } /* int memcached_init */
702 void module_register (void)
703 {
704 plugin_register_complex_config ("memcached", memcached_config);
705 plugin_register_init ("memcached", memcached_init);
706 }