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First pass through to make sure malloc is type safe
[m6w6/libmemcached] / libmemcached / hosts.cc
1 /* vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
2 *
3 * Libmemcached library
4 *
5 * Copyright (C) 2011 Data Differential, http://datadifferential.com/
6 * Copyright (C) 2006-2010 Brian Aker All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are
10 * met:
11 *
12 * * Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 *
15 * * Redistributions in binary form must reproduce the above
16 * copyright notice, this list of conditions and the following disclaimer
17 * in the documentation and/or other materials provided with the
18 * distribution.
19 *
20 * * The names of its contributors may not be used to endorse or
21 * promote products derived from this software without specific prior
22 * written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
25 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
26 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
27 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
28 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
29 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
30 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
31 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
32 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
33 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
34 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
35 *
36 */
37
38 #include <libmemcached/common.h>
39
40 #include <cmath>
41 #include <sys/time.h>
42
43 /* Protoypes (static) */
44 static memcached_return_t update_continuum(memcached_st *ptr);
45
46 static int compare_servers(const void *p1, const void *p2)
47 {
48 memcached_server_instance_st a= (memcached_server_instance_st)p1;
49 memcached_server_instance_st b= (memcached_server_instance_st)p2;
50
51 int return_value= strcmp(a->hostname, b->hostname);
52
53 if (return_value == 0)
54 {
55 return_value= (int) (a->port - b->port);
56 }
57
58 return return_value;
59 }
60
61 static void sort_hosts(memcached_st *ptr)
62 {
63 if (memcached_server_count(ptr))
64 {
65 memcached_server_write_instance_st instance;
66
67 qsort(memcached_server_list(ptr), memcached_server_count(ptr), sizeof(memcached_server_st), compare_servers);
68 instance= memcached_server_instance_fetch(ptr, 0);
69 instance->number_of_hosts= memcached_server_count(ptr);
70 }
71 }
72
73
74 memcached_return_t run_distribution(memcached_st *ptr)
75 {
76 if (ptr->flags.use_sort_hosts)
77 {
78 sort_hosts(ptr);
79 }
80
81 switch (ptr->distribution)
82 {
83 case MEMCACHED_DISTRIBUTION_CONSISTENT:
84 case MEMCACHED_DISTRIBUTION_CONSISTENT_KETAMA:
85 case MEMCACHED_DISTRIBUTION_CONSISTENT_KETAMA_SPY:
86 case MEMCACHED_DISTRIBUTION_CONSISTENT_WEIGHTED:
87 return update_continuum(ptr);
88
89 case MEMCACHED_DISTRIBUTION_VIRTUAL_BUCKET:
90 case MEMCACHED_DISTRIBUTION_MODULA:
91 break;
92
93 case MEMCACHED_DISTRIBUTION_RANDOM:
94 srandom((uint32_t) time(NULL));
95 break;
96
97 case MEMCACHED_DISTRIBUTION_CONSISTENT_MAX:
98 default:
99 assert_msg(0, "Invalid distribution type passed to run_distribution()");
100 }
101
102 return MEMCACHED_SUCCESS;
103 }
104
105 static uint32_t ketama_server_hash(const char *key, size_t key_length, uint32_t alignment)
106 {
107 unsigned char results[16];
108
109 libhashkit_md5_signature((unsigned char*)key, key_length, results);
110
111 return ((uint32_t) (results[3 + alignment * 4] & 0xFF) << 24)
112 | ((uint32_t) (results[2 + alignment * 4] & 0xFF) << 16)
113 | ((uint32_t) (results[1 + alignment * 4] & 0xFF) << 8)
114 | (results[0 + alignment * 4] & 0xFF);
115 }
116
117 static int continuum_item_cmp(const void *t1, const void *t2)
118 {
119 memcached_continuum_item_st *ct1= (memcached_continuum_item_st *)t1;
120 memcached_continuum_item_st *ct2= (memcached_continuum_item_st *)t2;
121
122 /* Why 153? Hmmm... */
123 WATCHPOINT_ASSERT(ct1->value != 153);
124 if (ct1->value == ct2->value)
125 return 0;
126 else if (ct1->value > ct2->value)
127 return 1;
128 else
129 return -1;
130 }
131
132 static memcached_return_t update_continuum(memcached_st *ptr)
133 {
134 uint32_t continuum_index= 0;
135 memcached_server_st *list;
136 uint32_t pointer_counter= 0;
137 uint32_t pointer_per_server= MEMCACHED_POINTS_PER_SERVER;
138 uint32_t pointer_per_hash= 1;
139 uint32_t live_servers= 0;
140 struct timeval now;
141
142 if (gettimeofday(&now, NULL))
143 {
144 return memcached_set_errno(*ptr, errno, MEMCACHED_AT);
145 }
146
147 list= memcached_server_list(ptr);
148
149 /* count live servers (those without a retry delay set) */
150 bool is_auto_ejecting= _is_auto_eject_host(ptr);
151 if (is_auto_ejecting)
152 {
153 live_servers= 0;
154 ptr->ketama.next_distribution_rebuild= 0;
155 for (uint32_t host_index= 0; host_index < memcached_server_count(ptr); ++host_index)
156 {
157 if (list[host_index].next_retry <= now.tv_sec)
158 {
159 live_servers++;
160 }
161 else
162 {
163 if (ptr->ketama.next_distribution_rebuild == 0 or list[host_index].next_retry < ptr->ketama.next_distribution_rebuild)
164 {
165 ptr->ketama.next_distribution_rebuild= list[host_index].next_retry;
166 }
167 }
168 }
169 }
170 else
171 {
172 live_servers= memcached_server_count(ptr);
173 }
174
175 uint64_t is_ketama_weighted= memcached_behavior_get(ptr, MEMCACHED_BEHAVIOR_KETAMA_WEIGHTED);
176 uint32_t points_per_server= (uint32_t) (is_ketama_weighted ? MEMCACHED_POINTS_PER_SERVER_KETAMA : MEMCACHED_POINTS_PER_SERVER);
177
178 if (not live_servers)
179 {
180 return MEMCACHED_SUCCESS;
181 }
182
183 if (live_servers > ptr->ketama.continuum_count)
184 {
185 memcached_continuum_item_st *new_ptr;
186
187 new_ptr= static_cast<memcached_continuum_item_st*>(libmemcached_realloc(ptr, ptr->ketama.continuum,
188 (live_servers + MEMCACHED_CONTINUUM_ADDITION) * points_per_server,
189 sizeof(memcached_continuum_item_st)));
190
191 if (new_ptr == 0)
192 {
193 return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
194 }
195
196 ptr->ketama.continuum= new_ptr;
197 ptr->ketama.continuum_count= live_servers + MEMCACHED_CONTINUUM_ADDITION;
198 }
199
200 uint64_t total_weight= 0;
201 if (is_ketama_weighted)
202 {
203 for (uint32_t host_index = 0; host_index < memcached_server_count(ptr); ++host_index)
204 {
205 if (is_auto_ejecting == false or list[host_index].next_retry <= now.tv_sec)
206 {
207 total_weight += list[host_index].weight;
208 }
209 }
210 }
211
212 for (uint32_t host_index= 0; host_index < memcached_server_count(ptr); ++host_index)
213 {
214 if (is_auto_ejecting and list[host_index].next_retry > now.tv_sec)
215 {
216 continue;
217 }
218
219 if (is_ketama_weighted)
220 {
221 float pct= (float)list[host_index].weight / (float)total_weight;
222 pointer_per_server= (uint32_t) ((floor((float) (pct * MEMCACHED_POINTS_PER_SERVER_KETAMA / 4 * (float)live_servers + 0.0000000001))) * 4);
223 pointer_per_hash= 4;
224 if (DEBUG)
225 {
226 printf("ketama_weighted:%s|%d|%llu|%u\n",
227 list[host_index].hostname,
228 list[host_index].port,
229 (unsigned long long)list[host_index].weight,
230 pointer_per_server);
231 }
232 }
233
234
235 if (ptr->distribution == MEMCACHED_DISTRIBUTION_CONSISTENT_KETAMA_SPY)
236 {
237 for (uint32_t pointer_index= 0;
238 pointer_index < pointer_per_server / pointer_per_hash;
239 pointer_index++)
240 {
241 char sort_host[MEMCACHED_MAX_HOST_SORT_LENGTH]= "";
242 int sort_host_length;
243
244 // Spymemcached ketema key format is: hostname/ip:port-index
245 // If hostname is not available then: /ip:port-index
246 sort_host_length= snprintf(sort_host, MEMCACHED_MAX_HOST_SORT_LENGTH,
247 "/%s:%u-%u",
248 list[host_index].hostname,
249 (uint32_t)list[host_index].port,
250 pointer_index);
251
252 if (sort_host_length >= MEMCACHED_MAX_HOST_SORT_LENGTH || sort_host_length < 0)
253 {
254 return memcached_set_error(*ptr, MEMCACHED_MEMORY_ALLOCATION_FAILURE, MEMCACHED_AT,
255 memcached_literal_param("snprintf(MEMCACHED_DEFAULT_COMMAND_SIZE)"));
256 }
257
258 if (DEBUG)
259 {
260 fprintf(stdout, "update_continuum: key is %s\n", sort_host);
261 }
262
263 if (is_ketama_weighted)
264 {
265 for (uint32_t x= 0; x < pointer_per_hash; x++)
266 {
267 uint32_t value= ketama_server_hash(sort_host, (size_t)sort_host_length, x);
268 ptr->ketama.continuum[continuum_index].index= host_index;
269 ptr->ketama.continuum[continuum_index++].value= value;
270 }
271 }
272 else
273 {
274 uint32_t value= hashkit_digest(&ptr->hashkit, sort_host, (size_t)sort_host_length);
275 ptr->ketama.continuum[continuum_index].index= host_index;
276 ptr->ketama.continuum[continuum_index++].value= value;
277 }
278 }
279 }
280 else
281 {
282 for (uint32_t pointer_index= 1;
283 pointer_index <= pointer_per_server / pointer_per_hash;
284 pointer_index++)
285 {
286 char sort_host[MEMCACHED_MAX_HOST_SORT_LENGTH]= "";
287 int sort_host_length;
288
289 if (list[host_index].port == MEMCACHED_DEFAULT_PORT)
290 {
291 sort_host_length= snprintf(sort_host, MEMCACHED_MAX_HOST_SORT_LENGTH,
292 "%s-%u",
293 list[host_index].hostname,
294 pointer_index - 1);
295 }
296 else
297 {
298 sort_host_length= snprintf(sort_host, MEMCACHED_MAX_HOST_SORT_LENGTH,
299 "%s:%u-%u",
300 list[host_index].hostname,
301 (uint32_t)list[host_index].port,
302 pointer_index - 1);
303 }
304
305 if (sort_host_length >= MEMCACHED_MAX_HOST_SORT_LENGTH || sort_host_length < 0)
306 {
307 return memcached_set_error(*ptr, MEMCACHED_MEMORY_ALLOCATION_FAILURE, MEMCACHED_AT,
308 memcached_literal_param("snprintf(MEMCACHED_DEFAULT_COMMAND_SIZE)"));
309 }
310
311 if (is_ketama_weighted)
312 {
313 for (uint32_t x = 0; x < pointer_per_hash; x++)
314 {
315 uint32_t value= ketama_server_hash(sort_host, (size_t)sort_host_length, x);
316 ptr->ketama.continuum[continuum_index].index= host_index;
317 ptr->ketama.continuum[continuum_index++].value= value;
318 }
319 }
320 else
321 {
322 uint32_t value= hashkit_digest(&ptr->hashkit, sort_host, (size_t)sort_host_length);
323 ptr->ketama.continuum[continuum_index].index= host_index;
324 ptr->ketama.continuum[continuum_index++].value= value;
325 }
326 }
327 }
328
329 pointer_counter+= pointer_per_server;
330 }
331
332 WATCHPOINT_ASSERT(ptr);
333 WATCHPOINT_ASSERT(ptr->ketama.continuum);
334 WATCHPOINT_ASSERT(memcached_server_count(ptr) * MEMCACHED_POINTS_PER_SERVER <= MEMCACHED_CONTINUUM_SIZE);
335 ptr->ketama.continuum_points_counter= pointer_counter;
336 qsort(ptr->ketama.continuum, ptr->ketama.continuum_points_counter, sizeof(memcached_continuum_item_st), continuum_item_cmp);
337
338 if (DEBUG)
339 {
340 for (uint32_t pointer_index= 0; memcached_server_count(ptr) && pointer_index < ((live_servers * MEMCACHED_POINTS_PER_SERVER) - 1); pointer_index++)
341 {
342 WATCHPOINT_ASSERT(ptr->ketama.continuum[pointer_index].value <= ptr->ketama.continuum[pointer_index + 1].value);
343 }
344 }
345
346 return MEMCACHED_SUCCESS;
347 }
348
349 static memcached_return_t server_add(memcached_st *ptr,
350 const memcached_string_t& hostname,
351 in_port_t port,
352 uint32_t weight,
353 memcached_connection_t type)
354 {
355 assert_msg(ptr, "Programmer mistake, somehow server_add() was passed a NULL memcached_st");
356
357 memcached_server_st *new_host_list= static_cast<memcached_server_st*>(libmemcached_realloc(ptr, memcached_server_list(ptr),
358 (ptr->number_of_hosts + 1),
359 sizeof(memcached_server_st)));
360
361 if (new_host_list == NULL)
362 {
363 return memcached_set_error(*ptr, MEMCACHED_MEMORY_ALLOCATION_FAILURE, MEMCACHED_AT);
364 }
365
366 memcached_server_list_set(ptr, new_host_list);
367
368 /* TODO: Check return type */
369 memcached_server_write_instance_st instance= memcached_server_instance_fetch(ptr, memcached_server_count(ptr));
370
371 if (__server_create_with(ptr, instance, hostname, port, weight, type) == NULL)
372 {
373 return memcached_set_error(*ptr, MEMCACHED_MEMORY_ALLOCATION_FAILURE, MEMCACHED_AT);
374 }
375
376 if (weight > 1)
377 {
378 ptr->ketama.weighted= true;
379 }
380
381 ptr->number_of_hosts++;
382
383 // @note we place the count in the bottom of the server list
384 instance= memcached_server_instance_fetch(ptr, 0);
385 memcached_servers_set_count(instance, memcached_server_count(ptr));
386
387 return run_distribution(ptr);
388 }
389
390
391 memcached_return_t memcached_server_push(memcached_st *ptr, const memcached_server_list_st list)
392 {
393 if (list == NULL)
394 {
395 return MEMCACHED_SUCCESS;
396 }
397
398 uint32_t count= memcached_server_list_count(list);
399
400 memcached_server_st *new_host_list;
401 new_host_list= static_cast<memcached_server_st*>(libmemcached_realloc(ptr, memcached_server_list(ptr),
402 (count + memcached_server_count(ptr)), sizeof(memcached_server_st)));
403
404 if (new_host_list == NULL)
405 {
406 return MEMCACHED_MEMORY_ALLOCATION_FAILURE;
407 }
408
409 memcached_server_list_set(ptr, new_host_list);
410
411 for (uint32_t x= 0; x < count; x++)
412 {
413 memcached_server_write_instance_st instance;
414
415 WATCHPOINT_ASSERT(list[x].hostname[0] != 0);
416
417 // We have extended the array, and now we will find it, and use it.
418 instance= memcached_server_instance_fetch(ptr, memcached_server_count(ptr));
419 WATCHPOINT_ASSERT(instance);
420
421 memcached_string_t hostname= { memcached_string_make_from_cstr(list[x].hostname) };
422 if (__server_create_with(ptr, instance,
423 hostname,
424 list[x].port, list[x].weight, list[x].type) == NULL)
425 {
426 return memcached_set_error(*ptr, MEMCACHED_MEMORY_ALLOCATION_FAILURE, MEMCACHED_AT);
427 }
428
429 if (list[x].weight > 1)
430 {
431 ptr->ketama.weighted= true;
432 }
433
434 ptr->number_of_hosts++;
435 }
436
437 // Provides backwards compatibility with server list.
438 {
439 memcached_server_write_instance_st instance;
440 instance= memcached_server_instance_fetch(ptr, 0);
441 instance->number_of_hosts= memcached_server_count(ptr);
442 }
443
444 return run_distribution(ptr);
445 }
446
447 memcached_return_t memcached_server_add_unix_socket(memcached_st *ptr,
448 const char *filename)
449 {
450 return memcached_server_add_unix_socket_with_weight(ptr, filename, 0);
451 }
452
453 memcached_return_t memcached_server_add_unix_socket_with_weight(memcached_st *ptr,
454 const char *filename,
455 uint32_t weight)
456 {
457 if (ptr == NULL)
458 {
459 return MEMCACHED_FAILURE;
460 }
461
462 memcached_string_t _filename= { memcached_string_make_from_cstr(filename) };
463 if (memcached_is_valid_servername(_filename) == false)
464 {
465 memcached_set_error(*ptr, MEMCACHED_INVALID_ARGUMENTS, MEMCACHED_AT, memcached_literal_param("Invalid filename for socket provided"));
466 }
467
468 return server_add(ptr, _filename, 0, weight, MEMCACHED_CONNECTION_UNIX_SOCKET);
469 }
470
471 memcached_return_t memcached_server_add_udp(memcached_st *ptr,
472 const char *hostname,
473 in_port_t port)
474 {
475 return memcached_server_add_udp_with_weight(ptr, hostname, port, 0);
476 }
477
478 memcached_return_t memcached_server_add_udp_with_weight(memcached_st *ptr,
479 const char *,
480 in_port_t,
481 uint32_t)
482 {
483 if (ptr == NULL)
484 {
485 return MEMCACHED_INVALID_ARGUMENTS;
486 }
487
488 return memcached_set_error(*ptr, MEMCACHED_DEPRECATED, MEMCACHED_AT);
489 }
490
491 memcached_return_t memcached_server_add(memcached_st *ptr,
492 const char *hostname,
493 in_port_t port)
494 {
495 return memcached_server_add_with_weight(ptr, hostname, port, 0);
496 }
497
498 memcached_return_t memcached_server_add_with_weight(memcached_st *ptr,
499 const char *hostname,
500 in_port_t port,
501 uint32_t weight)
502 {
503 if (ptr == NULL)
504 {
505 return MEMCACHED_INVALID_ARGUMENTS;
506 }
507
508 if (port == 0)
509 {
510 port= MEMCACHED_DEFAULT_PORT;
511 }
512
513 size_t hostname_length= hostname ? strlen(hostname) : 0;
514 if (hostname_length == 0)
515 {
516 hostname= "localhost";
517 hostname_length= memcached_literal_param_size("localhost");
518 }
519
520 memcached_string_t _hostname= { hostname, hostname_length };
521
522 if (memcached_is_valid_servername(_hostname) == false)
523 {
524 return memcached_set_error(*ptr, MEMCACHED_INVALID_ARGUMENTS, MEMCACHED_AT, memcached_literal_param("Invalid hostname provided"));
525 }
526
527 return server_add(ptr, _hostname, port, weight, _hostname.c_str[0] == '/' ? MEMCACHED_CONNECTION_UNIX_SOCKET : MEMCACHED_CONNECTION_TCP);
528 }
529
530 memcached_return_t memcached_server_add_parsed(memcached_st *ptr,
531 const char *hostname,
532 size_t hostname_length,
533 in_port_t port,
534 uint32_t weight)
535 {
536 char buffer[NI_MAXHOST];
537
538 memcpy(buffer, hostname, hostname_length);
539 buffer[hostname_length]= 0;
540
541 memcached_string_t _hostname= { buffer, hostname_length };
542
543 return server_add(ptr, _hostname,
544 port,
545 weight,
546 MEMCACHED_CONNECTION_TCP);
547 }
Resurrection of libmemcached https://launchpad.net/libmemcached