/[LeafOK_CVS]/lbbs/src/section_list.c
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Revision 1.43 - (show annotations)
Tue Oct 14 05:28:15 2025 UTC (5 months ago) by sysadm
Branch: MAIN
Changes since 1.42: +26 -0 lines
Content type: text/x-csrc
Refresh trie dict after update section name

1 /***************************************************************************
2 section_list.c - description
3 -------------------
4 Copyright : (C) 2004-2025 by Leaflet
5 Email : leaflet@leafok.com
6 ***************************************************************************/
7
8 /***************************************************************************
9 * *
10 * This program is free software; you can redistribute it and/or modify *
11 * it under the terms of the GNU General Public License as published by *
12 * the Free Software Foundation; either version 3 of the License, or *
13 * (at your option) any later version. *
14 * *
15 ***************************************************************************/
16
17 #include "log.h"
18 #include "section_list.h"
19 #include "trie_dict.h"
20 #include <errno.h>
21 #include <signal.h>
22 #include <stdio.h>
23 #include <stdlib.h>
24 #include <string.h>
25 #include <unistd.h>
26 #include <sys/ipc.h>
27 #include <sys/param.h>
28 #include <sys/sem.h>
29 #include <sys/shm.h>
30
31 #ifdef _SEM_SEMUN_UNDEFINED
32 union semun
33 {
34 int val; /* Value for SETVAL */
35 struct semid_ds *buf; /* Buffer for IPC_STAT, IPC_SET */
36 unsigned short *array; /* Array for GETALL, SETALL */
37 struct seminfo *__buf; /* Buffer for IPC_INFO
38 (Linux-specific) */
39 };
40 #endif // #ifdef _SEM_SEMUN_UNDEFINED
41
42 #define SECTION_TRY_LOCK_WAIT_TIME 1 // second
43 #define SECTION_TRY_LOCK_TIMES 10
44
45 #define ARTICLE_BLOCK_PER_SHM 1000 // sizeof(ARTICLE_BLOCK) * ARTICLE_BLOCK_PER_SHM is the size of each shm segment to allocate
46 #define ARTICLE_BLOCK_SHM_COUNT_LIMIT 80 // limited by length (8-bit) of proj_id in ftok(path, proj_id)
47 #define ARTICLE_BLOCK_PER_POOL (ARTICLE_BLOCK_PER_SHM * ARTICLE_BLOCK_SHM_COUNT_LIMIT)
48
49 #define CALCULATE_PAGE_THRESHOLD 100 // Adjust to tune performance of moving topic between sections
50
51 #define SID_STR_LEN 5 // 32-bit + NULL
52
53 struct article_block_t
54 {
55 ARTICLE articles[ARTICLE_PER_BLOCK];
56 int article_count;
57 struct article_block_t *p_next_block;
58 };
59 typedef struct article_block_t ARTICLE_BLOCK;
60
61 struct article_block_pool_t
62 {
63 int shmid;
64 struct
65 {
66 int shmid;
67 void *p_shm;
68 } shm_pool[ARTICLE_BLOCK_SHM_COUNT_LIMIT];
69 int shm_count;
70 ARTICLE_BLOCK *p_block_free_list;
71 ARTICLE_BLOCK *p_block[ARTICLE_BLOCK_PER_POOL];
72 int block_count;
73 };
74 typedef struct article_block_pool_t ARTICLE_BLOCK_POOL;
75
76 static ARTICLE_BLOCK_POOL *p_article_block_pool = NULL;
77
78 SECTION_LIST_POOL *p_section_list_pool = NULL;
79
80 int article_block_init(const char *filename, int block_count)
81 {
82 int shmid;
83 int proj_id;
84 key_t key;
85 size_t size;
86 void *p_shm;
87 int i;
88 int block_count_in_shm;
89 ARTICLE_BLOCK *p_block_in_shm;
90 ARTICLE_BLOCK **pp_block_next;
91
92 if (p_article_block_pool != NULL)
93 {
94 log_error("article_block_pool already initialized\n");
95 return -1;
96 }
97
98 if (block_count <= 0 || block_count > ARTICLE_BLOCK_PER_POOL)
99 {
100 log_error("article_block_count exceed limit %d\n", ARTICLE_BLOCK_PER_POOL);
101 return -2;
102 }
103
104 // Allocate shared memory
105 proj_id = ARTICLE_BLOCK_SHM_COUNT_LIMIT; // keep different from proj_id used to create block shm
106 key = ftok(filename, proj_id);
107 if (key == -1)
108 {
109 log_error("ftok(%s, %d) error (%d)\n", filename, proj_id, errno);
110 return -3;
111 }
112
113 size = sizeof(ARTICLE_BLOCK_POOL);
114 shmid = shmget(key, size, IPC_CREAT | IPC_EXCL | 0600);
115 if (shmid == -1)
116 {
117 log_error("shmget(article_block_pool_shm, size = %d) error (%d)\n", size, errno);
118 return -3;
119 }
120 p_shm = shmat(shmid, NULL, 0);
121 if (p_shm == (void *)-1)
122 {
123 log_error("shmat(shmid = %d) error (%d)\n", shmid, errno);
124 return -3;
125 }
126
127 p_article_block_pool = p_shm;
128 p_article_block_pool->shmid = shmid;
129
130 p_article_block_pool->shm_count = 0;
131 pp_block_next = &(p_article_block_pool->p_block_free_list);
132
133 while (block_count > 0)
134 {
135 block_count_in_shm = MIN(block_count, ARTICLE_BLOCK_PER_SHM);
136 block_count -= block_count_in_shm;
137
138 proj_id = p_article_block_pool->shm_count;
139 key = ftok(filename, proj_id);
140 if (key == -1)
141 {
142 log_error("ftok(%s, %d) error (%d)\n", filename, proj_id, errno);
143 article_block_cleanup();
144 return -3;
145 }
146
147 size = sizeof(ARTICLE_BLOCK) * (size_t)block_count_in_shm;
148 shmid = shmget(key, size, IPC_CREAT | IPC_EXCL | 0600);
149 if (shmid == -1)
150 {
151 log_error("shmget(shm_index = %d, size = %d) error (%d)\n", p_article_block_pool->shm_count, size, errno);
152 article_block_cleanup();
153 return -3;
154 }
155 p_shm = shmat(shmid, NULL, 0);
156 if (p_shm == (void *)-1)
157 {
158 log_error("shmat(shmid = %d) error (%d)\n", shmid, errno);
159 article_block_cleanup();
160 return -3;
161 }
162
163 (p_article_block_pool->shm_pool + p_article_block_pool->shm_count)->shmid = shmid;
164 (p_article_block_pool->shm_pool + p_article_block_pool->shm_count)->p_shm = p_shm;
165 p_article_block_pool->shm_count++;
166
167 p_block_in_shm = p_shm;
168 *pp_block_next = p_block_in_shm;
169
170 for (i = 0; i < block_count_in_shm; i++)
171 {
172 if (i < block_count_in_shm - 1)
173 {
174 (p_block_in_shm + i)->p_next_block = (p_block_in_shm + i + 1);
175 }
176 else
177 {
178 (p_block_in_shm + i)->p_next_block = NULL;
179 pp_block_next = &((p_block_in_shm + i)->p_next_block);
180 }
181 }
182 }
183
184 p_article_block_pool->block_count = 0;
185
186 return 0;
187 }
188
189 void article_block_cleanup(void)
190 {
191 int shmid;
192
193 if (p_article_block_pool == NULL)
194 {
195 return;
196 }
197
198 for (int i = 0; i < p_article_block_pool->shm_count; i++)
199 {
200 if (shmdt((p_article_block_pool->shm_pool + i)->p_shm) == -1)
201 {
202 log_error("shmdt(shmid = %d) error (%d)\n", (p_article_block_pool->shm_pool + i)->shmid, errno);
203 }
204
205 if (shmctl((p_article_block_pool->shm_pool + i)->shmid, IPC_RMID, NULL) == -1)
206 {
207 log_error("shmctl(shmid = %d, IPC_RMID) error (%d)\n", (p_article_block_pool->shm_pool + i)->shmid, errno);
208 }
209 }
210
211 shmid = p_article_block_pool->shmid;
212
213 if (shmdt(p_article_block_pool) == -1)
214 {
215 log_error("shmdt(shmid = %d) error (%d)\n", shmid, errno);
216 }
217
218 if (shmctl(shmid, IPC_RMID, NULL) == -1)
219 {
220 log_error("shmctl(shmid = %d, IPC_RMID) error (%d)\n", shmid, errno);
221 }
222
223 p_article_block_pool = NULL;
224 }
225
226 int set_article_block_shm_readonly(void)
227 {
228 int shmid;
229 void *p_shm;
230 int i;
231
232 if (p_article_block_pool == NULL)
233 {
234 log_error("article_block_pool not initialized\n");
235 return -1;
236 }
237
238 for (i = 0; i < p_article_block_pool->shm_count; i++)
239 {
240 shmid = (p_article_block_pool->shm_pool + i)->shmid;
241
242 // Remap shared memory in read-only mode
243 p_shm = shmat(shmid, (p_article_block_pool->shm_pool + i)->p_shm, SHM_RDONLY | SHM_REMAP);
244 if (p_shm == (void *)-1)
245 {
246 log_error("shmat(article_block_pool shmid = %d) error (%d)\n", shmid, errno);
247 return -2;
248 }
249 }
250
251 return 0;
252 }
253
254 int detach_article_block_shm(void)
255 {
256 int shmid;
257
258 if (p_article_block_pool == NULL)
259 {
260 return -1;
261 }
262
263 for (int i = 0; i < p_article_block_pool->shm_count; i++)
264 {
265 if ((p_article_block_pool->shm_pool + i)->p_shm != NULL && shmdt((p_article_block_pool->shm_pool + i)->p_shm) == -1)
266 {
267 log_error("shmdt(shmid = %d) error (%d)\n", (p_article_block_pool->shm_pool + i)->shmid, errno);
268 return -2;
269 }
270 }
271
272 shmid = p_article_block_pool->shmid;
273
274 if (shmdt(p_article_block_pool) == -1)
275 {
276 log_error("shmdt(shmid = %d) error (%d)\n", shmid, errno);
277 return -3;
278 }
279
280 p_article_block_pool = NULL;
281
282 return 0;
283 }
284
285 inline static ARTICLE_BLOCK *pop_free_article_block(void)
286 {
287 ARTICLE_BLOCK *p_block = NULL;
288
289 if (p_article_block_pool->p_block_free_list != NULL)
290 {
291 p_block = p_article_block_pool->p_block_free_list;
292 p_article_block_pool->p_block_free_list = p_block->p_next_block;
293 p_block->p_next_block = NULL;
294 p_block->article_count = 0;
295 }
296
297 return p_block;
298 }
299
300 inline static void push_free_article_block(ARTICLE_BLOCK *p_block)
301 {
302 p_block->p_next_block = p_article_block_pool->p_block_free_list;
303 p_article_block_pool->p_block_free_list = p_block;
304 }
305
306 int article_block_reset(void)
307 {
308 ARTICLE_BLOCK *p_block;
309
310 if (p_article_block_pool == NULL)
311 {
312 log_error("article_block_pool not initialized\n");
313 return -1;
314 }
315
316 while (p_article_block_pool->block_count > 0)
317 {
318 p_article_block_pool->block_count--;
319 p_block = p_article_block_pool->p_block[p_article_block_pool->block_count];
320 push_free_article_block(p_block);
321 }
322
323 return 0;
324 }
325
326 ARTICLE *article_block_find_by_aid(int32_t aid)
327 {
328 ARTICLE_BLOCK *p_block;
329 int left;
330 int right;
331 int mid;
332
333 if (p_article_block_pool == NULL)
334 {
335 log_error("article_block_pool not initialized\n");
336 return NULL;
337 }
338
339 if (p_article_block_pool->block_count == 0) // empty
340 {
341 return NULL;
342 }
343
344 left = 0;
345 right = p_article_block_pool->block_count;
346
347 // aid in the range [ head aid of blocks[left], tail aid of blocks[right - 1] ]
348 while (left < right - 1)
349 {
350 // get block offset no less than mid value of left and right block offsets
351 mid = (left + right) / 2 + (right - left) % 2;
352
353 if (mid >= p_article_block_pool->block_count)
354 {
355 log_error("block(mid = %d) is out of boundary\n", mid);
356 return NULL;
357 }
358
359 if (aid < p_article_block_pool->p_block[mid]->articles[0].aid)
360 {
361 right = mid;
362 }
363 else
364 {
365 left = mid;
366 }
367 }
368
369 p_block = p_article_block_pool->p_block[left];
370
371 left = 0;
372 right = p_block->article_count - 1;
373
374 // aid in the range [ aid of articles[left], aid of articles[right] ]
375 while (left < right)
376 {
377 mid = (left + right) / 2;
378
379 if (aid <= p_block->articles[mid].aid)
380 {
381 right = mid;
382 }
383 else
384 {
385 left = mid + 1;
386 }
387 }
388
389 if (aid != p_block->articles[left].aid) // not found
390 {
391 return NULL;
392 }
393
394 return (p_block->articles + left); // found
395 }
396
397 ARTICLE *article_block_find_by_index(int index)
398 {
399 ARTICLE_BLOCK *p_block;
400
401 if (p_article_block_pool == NULL)
402 {
403 log_error("article_block_pool not initialized\n");
404 return NULL;
405 }
406
407 if (index < 0 || index / ARTICLE_PER_BLOCK >= p_article_block_pool->block_count)
408 {
409 log_error("article_block_find_by_index(%d) is out of boundary of block [0, %d)\n", index, p_article_block_pool->block_count);
410 return NULL;
411 }
412
413 p_block = p_article_block_pool->p_block[index / ARTICLE_PER_BLOCK];
414
415 if (index % ARTICLE_PER_BLOCK >= p_block->article_count)
416 {
417 log_error("article_block_find_by_index(%d) is out of boundary of article [0, %d)\n", index, p_block->article_count);
418 return NULL;
419 }
420
421 return (p_block->articles + (index % ARTICLE_PER_BLOCK));
422 }
423
424 extern int section_list_init(const char *filename)
425 {
426 int semid;
427 int shmid;
428 int proj_id;
429 key_t key;
430 size_t size;
431 void *p_shm;
432 union semun arg;
433 int i;
434
435 if (p_section_list_pool != NULL)
436 {
437 section_list_cleanup();
438 }
439
440 proj_id = (int)(time(NULL) % getpid());
441 key = ftok(filename, proj_id);
442 if (key == -1)
443 {
444 log_error("ftok(%s, %d) error (%d)\n", filename, proj_id, errno);
445 return -3;
446 }
447
448 // Allocate shared memory
449 size = sizeof(SECTION_LIST_POOL);
450 shmid = shmget(key, size, IPC_CREAT | IPC_EXCL | 0600);
451 if (shmid == -1)
452 {
453 log_error("shmget(section_list_pool_shm, size = %d) error (%d)\n", size, errno);
454 return -3;
455 }
456 p_shm = shmat(shmid, NULL, 0);
457 if (p_shm == (void *)-1)
458 {
459 log_error("shmat(shmid = %d) error (%d)\n", shmid, errno);
460 return -3;
461 }
462
463 p_section_list_pool = p_shm;
464 p_section_list_pool->shmid = shmid;
465 p_section_list_pool->section_count = 0;
466
467 // Allocate semaphore as section locks
468 size = 2 * (BBS_max_section + 1); // r_sem and w_sem per section, the last pair for all sections
469 semid = semget(key, (int)size, IPC_CREAT | IPC_EXCL | 0600);
470 if (semid == -1)
471 {
472 log_error("semget(section_list_pool_sem, size = %d) error (%d)\n", size, errno);
473 return -3;
474 }
475
476 // Initialize sem value to 0
477 arg.val = 0;
478 for (i = 0; i < size; i++)
479 {
480 if (semctl(semid, i, SETVAL, arg) == -1)
481 {
482 log_error("semctl(section_list_pool_sem, SETVAL) error (%d)\n", errno);
483 return -3;
484 }
485 }
486
487 p_section_list_pool->semid = semid;
488
489 p_section_list_pool->p_trie_dict_section_by_name = trie_dict_create();
490 if (p_section_list_pool->p_trie_dict_section_by_name == NULL)
491 {
492 log_error("trie_dict_create() OOM\n", BBS_max_section);
493 return -2;
494 }
495
496 p_section_list_pool->p_trie_dict_section_by_sid = trie_dict_create();
497 if (p_section_list_pool->p_trie_dict_section_by_sid == NULL)
498 {
499 log_error("trie_dict_create() OOM\n", BBS_max_section);
500 return -2;
501 }
502
503 return 0;
504 }
505
506 void section_list_cleanup(void)
507 {
508 int shmid;
509
510 if (p_section_list_pool == NULL)
511 {
512 return;
513 }
514
515 if (p_section_list_pool->p_trie_dict_section_by_name != NULL)
516 {
517 trie_dict_destroy(p_section_list_pool->p_trie_dict_section_by_name);
518 p_section_list_pool->p_trie_dict_section_by_name = NULL;
519 }
520
521 if (p_section_list_pool->p_trie_dict_section_by_sid != NULL)
522 {
523 trie_dict_destroy(p_section_list_pool->p_trie_dict_section_by_sid);
524 p_section_list_pool->p_trie_dict_section_by_sid = NULL;
525 }
526
527 shmid = p_section_list_pool->shmid;
528
529 if (semctl(p_section_list_pool->semid, 0, IPC_RMID) == -1)
530 {
531 log_error("semctl(semid = %d, IPC_RMID) error (%d)\n", p_section_list_pool->semid, errno);
532 }
533
534 if (shmdt(p_section_list_pool) == -1)
535 {
536 log_error("shmdt(shmid = %d) error (%d)\n", shmid, errno);
537 }
538
539 if (shmctl(shmid, IPC_RMID, NULL) == -1)
540 {
541 log_error("shmctl(shmid = %d, IPC_RMID) error (%d)\n", shmid, errno);
542 }
543
544 p_section_list_pool = NULL;
545 }
546
547 int set_section_list_shm_readonly(void)
548 {
549 int shmid;
550 void *p_shm;
551
552 if (p_section_list_pool == NULL)
553 {
554 log_error("p_section_list_pool not initialized\n");
555 return -1;
556 }
557
558 shmid = p_section_list_pool->shmid;
559
560 // Remap shared memory in read-only mode
561 p_shm = shmat(shmid, p_section_list_pool, SHM_RDONLY | SHM_REMAP);
562 if (p_shm == (void *)-1)
563 {
564 log_error("shmat(section_list_pool shmid = %d) error (%d)\n", shmid, errno);
565 return -3;
566 }
567
568 p_section_list_pool = p_shm;
569
570 return 0;
571 }
572
573 int detach_section_list_shm(void)
574 {
575 if (p_section_list_pool != NULL && shmdt(p_section_list_pool) == -1)
576 {
577 log_error("shmdt(section_list_pool) error (%d)\n", errno);
578 return -1;
579 }
580
581 p_section_list_pool = NULL;
582
583 return 0;
584 }
585
586 inline static void sid_to_str(int32_t sid, char *p_sid_str)
587 {
588 uint32_t u_sid;
589 int i;
590
591 u_sid = (uint32_t)sid;
592 for (i = 0; i < SID_STR_LEN - 1; i++)
593 {
594 p_sid_str[i] = (char)(u_sid % 255 + 1);
595 u_sid /= 255;
596 }
597 p_sid_str[i] = '\0';
598 }
599
600 SECTION_LIST *section_list_create(int32_t sid, const char *sname, const char *stitle, const char *master_list)
601 {
602 SECTION_LIST *p_section;
603 char sid_str[SID_STR_LEN];
604
605 if (p_section_list_pool == NULL)
606 {
607 log_error("session_list_pool not initialized\n");
608 return NULL;
609 }
610
611 if (p_section_list_pool->section_count >= BBS_max_section)
612 {
613 log_error("section_count reach limit %d >= %d\n", p_section_list_pool->section_count, BBS_max_section);
614 return NULL;
615 }
616
617 sid_to_str(sid, sid_str);
618
619 p_section = p_section_list_pool->sections + p_section_list_pool->section_count;
620
621 p_section->sid = sid;
622 p_section->ex_menu_tm = 0;
623
624 strncpy(p_section->sname, sname, sizeof(p_section->sname) - 1);
625 p_section->sname[sizeof(p_section->sname) - 1] = '\0';
626
627 strncpy(p_section->stitle, stitle, sizeof(p_section->stitle) - 1);
628 p_section->stitle[sizeof(p_section->stitle) - 1] = '\0';
629
630 strncpy(p_section->master_list, master_list, sizeof(p_section->master_list) - 1);
631 p_section->master_list[sizeof(p_section->master_list) - 1] = '\0';
632
633 if (trie_dict_set(p_section_list_pool->p_trie_dict_section_by_name, sname, p_section_list_pool->section_count) != 1)
634 {
635 log_error("trie_dict_set(section, %s, %d) error\n", sname, p_section_list_pool->section_count);
636 return NULL;
637 }
638
639 if (trie_dict_set(p_section_list_pool->p_trie_dict_section_by_sid, sid_str, p_section_list_pool->section_count) != 1)
640 {
641 log_error("trie_dict_set(section, %d, %d) error\n", sid, p_section_list_pool->section_count);
642 return NULL;
643 }
644
645 section_list_reset_articles(p_section);
646
647 p_section_list_pool->section_count++;
648
649 return p_section;
650 }
651
652 int section_list_update(SECTION_LIST *p_section, const char *sname, const char *stitle, const char *master_list)
653 {
654 if (p_section == NULL || sname == NULL || stitle == NULL || master_list == NULL)
655 {
656 log_error("NULL pointer error\n");
657 return -1;
658 }
659
660 strncpy(p_section->sname, sname, sizeof(p_section->sname) - 1);
661 p_section->sname[sizeof(p_section->sname) - 1] = '\0';
662
663 strncpy(p_section->stitle, stitle, sizeof(p_section->stitle) - 1);
664 p_section->stitle[sizeof(p_section->stitle) - 1] = '\0';
665
666 strncpy(p_section->master_list, master_list, sizeof(p_section->master_list) - 1);
667 p_section->master_list[sizeof(p_section->master_list) - 1] = '\0';
668
669 if (trie_dict_set(p_section_list_pool->p_trie_dict_section_by_name, sname, p_section_list_pool->section_count) != 1)
670 {
671 log_error("trie_dict_set(section, %s, %d) error\n", sname, p_section_list_pool->section_count);
672 return -2;
673 }
674
675 return 0;
676 }
677
678 void section_list_reset_articles(SECTION_LIST *p_section)
679 {
680 p_section->article_count = 0;
681 p_section->topic_count = 0;
682 p_section->visible_article_count = 0;
683 p_section->visible_topic_count = 0;
684 p_section->p_article_head = NULL;
685 p_section->p_article_tail = NULL;
686
687 p_section->page_count = 0;
688 p_section->last_page_visible_article_count = 0;
689
690 p_section->ontop_article_count = 0;
691 }
692
693 SECTION_LIST *section_list_find_by_name(const char *sname)
694 {
695 int64_t index;
696 int ret;
697
698 if (p_section_list_pool == NULL)
699 {
700 log_error("section_list not initialized\n");
701 return NULL;
702 }
703
704 ret = trie_dict_get(p_section_list_pool->p_trie_dict_section_by_name, sname, &index);
705 if (ret < 0)
706 {
707 log_error("trie_dict_get(section, %s) error\n", sname);
708 return NULL;
709 }
710 else if (ret == 0)
711 {
712 return NULL;
713 }
714
715 return (p_section_list_pool->sections + index);
716 }
717
718 SECTION_LIST *section_list_find_by_sid(int32_t sid)
719 {
720 int64_t index;
721 int ret;
722 char sid_str[SID_STR_LEN];
723
724 if (p_section_list_pool == NULL)
725 {
726 log_error("section_list not initialized\n");
727 return NULL;
728 }
729
730 sid_to_str(sid, sid_str);
731
732 ret = trie_dict_get(p_section_list_pool->p_trie_dict_section_by_sid, sid_str, &index);
733 if (ret < 0)
734 {
735 log_error("trie_dict_get(section, %d) error\n", sid);
736 return NULL;
737 }
738 else if (ret == 0)
739 {
740 return NULL;
741 }
742
743 return (p_section_list_pool->sections + index);
744 }
745
746 int section_list_append_article(SECTION_LIST *p_section, const ARTICLE *p_article_src)
747 {
748 ARTICLE_BLOCK *p_block;
749 int32_t last_aid = 0;
750 ARTICLE *p_article;
751 ARTICLE *p_topic_head;
752 ARTICLE *p_topic_tail;
753
754 if (p_section == NULL || p_article_src == NULL)
755 {
756 log_error("NULL pointer error\n");
757 return -1;
758 }
759
760 if (p_article_block_pool == NULL)
761 {
762 log_error("article_block_pool not initialized\n");
763 return -1;
764 }
765
766 if (p_section->sid != p_article_src->sid)
767 {
768 log_error("section_list_append_article() error: section sid %d != article sid %d\n", p_section->sid, p_article_src->sid);
769 return -2;
770 }
771
772 if (p_section->article_count >= BBS_article_limit_per_section)
773 {
774 log_error("section_list_append_article() error: article_count reach limit in section %d\n", p_section->sid);
775 return -2;
776 }
777
778 if (p_article_block_pool->block_count == 0 ||
779 p_article_block_pool->p_block[p_article_block_pool->block_count - 1]->article_count >= ARTICLE_PER_BLOCK)
780 {
781 if ((p_block = pop_free_article_block()) == NULL)
782 {
783 log_error("pop_free_article_block() error\n");
784 return -2;
785 }
786
787 if (p_article_block_pool->block_count > 0)
788 {
789 last_aid = p_article_block_pool->p_block[p_article_block_pool->block_count - 1]->articles[ARTICLE_PER_BLOCK - 1].aid;
790 }
791
792 p_article_block_pool->p_block[p_article_block_pool->block_count] = p_block;
793 p_article_block_pool->block_count++;
794 }
795 else
796 {
797 p_block = p_article_block_pool->p_block[p_article_block_pool->block_count - 1];
798 last_aid = p_block->articles[p_block->article_count - 1].aid;
799 }
800
801 // AID of articles should be strictly ascending
802 if (p_article_src->aid <= last_aid)
803 {
804 log_error("section_list_append_article(aid=%d) error: last_aid=%d\n", p_article_src->aid, last_aid);
805 return -3;
806 }
807
808 p_article = (p_block->articles + p_block->article_count);
809 p_block->article_count++;
810 p_section->article_count++;
811
812 // Copy article data
813 *p_article = *p_article_src;
814
815 if (p_article->visible)
816 {
817 p_section->visible_article_count++;
818 }
819
820 // Link appended article as tail node of topic bi-directional list
821 if (p_article->tid != 0)
822 {
823 p_topic_head = article_block_find_by_aid(p_article->tid);
824 if (p_topic_head == NULL)
825 {
826 log_error("search head of topic (aid=%d) error\n", p_article->tid);
827 return -4;
828 }
829
830 p_topic_tail = p_topic_head->p_topic_prior;
831 if (p_topic_tail == NULL)
832 {
833 log_error("tail of topic (aid=%d) is NULL\n", p_article->tid);
834 return -4;
835 }
836 }
837 else
838 {
839 p_section->topic_count++;
840
841 if (p_article->visible)
842 {
843 p_section->visible_topic_count++;
844 }
845
846 p_topic_head = p_article;
847 p_topic_tail = p_article;
848 }
849
850 p_article->p_topic_prior = p_topic_tail;
851 p_article->p_topic_next = p_topic_head;
852 p_topic_head->p_topic_prior = p_article;
853 p_topic_tail->p_topic_next = p_article;
854
855 // Link appended article as tail node of article bi-directional list
856 if (p_section->p_article_head == NULL)
857 {
858 p_section->p_article_head = p_article;
859 p_section->p_article_tail = p_article;
860 }
861 p_article->p_prior = p_section->p_article_tail;
862 p_article->p_next = p_section->p_article_head;
863 p_section->p_article_head->p_prior = p_article;
864 p_section->p_article_tail->p_next = p_article;
865 p_section->p_article_tail = p_article;
866
867 // Update page
868 if ((p_article->visible && p_section->last_page_visible_article_count % BBS_article_limit_per_page == 0) ||
869 p_section->article_count == 1)
870 {
871 p_section->p_page_first_article[p_section->page_count] = p_article;
872 p_section->page_count++;
873 p_section->last_page_visible_article_count = 0;
874 }
875
876 if (p_article->visible)
877 {
878 p_section->last_page_visible_article_count++;
879 }
880
881 if (p_article->ontop && section_list_update_article_ontop(p_section, p_article) < 0)
882 {
883 log_error("section_list_update_article_ontop(sid=%d, aid=%d) error\n",
884 p_section->sid, p_article->aid);
885 return -5;
886 }
887
888 return 0;
889 }
890
891 int section_list_set_article_visible(SECTION_LIST *p_section, int32_t aid, int8_t visible)
892 {
893 ARTICLE *p_article;
894 ARTICLE *p_reply;
895 int affected_count = 0;
896
897 if (p_section == NULL)
898 {
899 log_error("NULL pointer error\n");
900 return -1;
901 }
902
903 p_article = article_block_find_by_aid(aid);
904 if (p_article == NULL)
905 {
906 return -1; // Not found
907 }
908
909 if (p_section->sid != p_article->sid)
910 {
911 log_error("Inconsistent section sid %d != article sid %d\n", p_section->sid, p_article->sid);
912 return -2;
913 }
914
915 if (p_article->visible == visible)
916 {
917 return 0; // Already set
918 }
919
920 if (visible == 0) // 1 -> 0
921 {
922 p_section->visible_article_count--;
923
924 if (p_article->tid == 0)
925 {
926 p_section->visible_topic_count--;
927
928 // Set related visible replies to invisible
929 for (p_reply = p_article->p_topic_next; p_reply->tid != 0; p_reply = p_reply->p_topic_next)
930 {
931 if (p_reply->tid != aid)
932 {
933 log_error("Inconsistent tid = %d found in reply %d of topic %d\n", p_reply->tid, p_reply->aid, aid);
934 continue;
935 }
936
937 if (p_reply->visible == 1)
938 {
939 p_reply->visible = 0;
940 p_section->visible_article_count--;
941 affected_count++;
942 }
943 }
944 }
945 }
946 else // 0 -> 1
947 {
948 p_section->visible_article_count++;
949
950 if (p_article->tid == 0)
951 {
952 p_section->visible_topic_count++;
953 }
954 }
955
956 p_article->visible = visible;
957 affected_count++;
958
959 return affected_count;
960 }
961
962 int section_list_update_article_ontop(SECTION_LIST *p_section, ARTICLE *p_article)
963 {
964 int i;
965
966 if (p_section == NULL || p_article == NULL)
967 {
968 log_error("NULL pointer error\n");
969 return -1;
970 }
971
972 if (p_section->sid != p_article->sid)
973 {
974 log_error("Inconsistent section sid %d != article sid %d\n", p_section->sid, p_article->sid);
975 return -2;
976 }
977
978 if (p_article->ontop)
979 {
980 for (i = 0; i < p_section->ontop_article_count; i++)
981 {
982 if (p_section->p_ontop_articles[i]->aid == p_article->aid)
983 {
984 log_error("Inconsistent state found: article %d already ontop in section %d\n", p_article->aid, p_section->sid);
985 return 0;
986 }
987 else if (p_section->p_ontop_articles[i]->aid > p_article->aid)
988 {
989 break;
990 }
991 }
992
993 // Remove the oldest one if the array of ontop articles is full
994 if (p_section->ontop_article_count >= BBS_ontop_article_limit_per_section)
995 {
996 if (i == 0) // p_article is the oldest one
997 {
998 return 0;
999 }
1000 memmove((void *)(p_section->p_ontop_articles),
1001 (void *)(p_section->p_ontop_articles + 1),
1002 sizeof(ARTICLE *) * (size_t)(i - 1));
1003 p_section->ontop_article_count--;
1004 i--;
1005 }
1006 else
1007 {
1008 memmove((void *)(p_section->p_ontop_articles + i + 1),
1009 (void *)(p_section->p_ontop_articles + i),
1010 sizeof(ARTICLE *) * (size_t)(p_section->ontop_article_count - i));
1011 }
1012
1013 p_section->p_ontop_articles[i] = p_article;
1014 p_section->ontop_article_count++;
1015
1016 // TODO: debug
1017 }
1018 else // ontop == 0
1019 {
1020 for (i = 0; i < p_section->ontop_article_count; i++)
1021 {
1022 if (p_section->p_ontop_articles[i]->aid == p_article->aid)
1023 {
1024 break;
1025 }
1026 }
1027 if (i == p_section->ontop_article_count) // not found
1028 {
1029 log_error("Inconsistent state found: article %d not ontop in section %d\n", p_article->aid, p_section->sid);
1030 return 0;
1031 }
1032
1033 memmove((void *)(p_section->p_ontop_articles + i),
1034 (void *)(p_section->p_ontop_articles + i + 1),
1035 sizeof(ARTICLE *) * (size_t)(p_section->ontop_article_count - i - 1));
1036 p_section->ontop_article_count--;
1037 }
1038
1039 return 0;
1040 }
1041
1042 int section_list_page_count_with_ontop(SECTION_LIST *p_section)
1043 {
1044 int page_count;
1045
1046 if (p_section == NULL)
1047 {
1048 log_error("NULL pointer error\n");
1049 return -1;
1050 }
1051
1052 page_count = p_section->page_count - (p_section->last_page_visible_article_count > 0 ? 1 : 0) +
1053 (p_section->last_page_visible_article_count + p_section->ontop_article_count) / BBS_article_limit_per_page +
1054 ((p_section->last_page_visible_article_count + p_section->ontop_article_count) % BBS_article_limit_per_page == 0 ? 0 : 1);
1055
1056 return page_count;
1057 }
1058
1059 int section_list_page_article_count_with_ontop(SECTION_LIST *p_section, int32_t page_id)
1060 {
1061 if (p_section == NULL)
1062 {
1063 log_error("NULL pointer error\n");
1064 return -1;
1065 }
1066
1067 if (page_id < p_section->page_count - 1)
1068 {
1069 return BBS_article_limit_per_page;
1070 }
1071 else // if (page_id >= p_section->page_count - 1)
1072 {
1073 return MAX(0, (p_section->last_page_visible_article_count + p_section->ontop_article_count -
1074 BBS_article_limit_per_page * (page_id - p_section->page_count + 1)));
1075 }
1076 }
1077
1078 ARTICLE *section_list_find_article_with_offset(SECTION_LIST *p_section, int32_t aid, int32_t *p_page, int32_t *p_offset, ARTICLE **pp_next)
1079 {
1080 ARTICLE *p_article;
1081 int left;
1082 int right;
1083 int mid;
1084
1085 *p_page = -1;
1086 *p_offset = -1;
1087 *pp_next = NULL;
1088
1089 if (p_section == NULL)
1090 {
1091 log_error("NULL pointer error\n");
1092 return NULL;
1093 }
1094
1095 if (p_section->article_count == 0) // empty
1096 {
1097 *p_page = 0;
1098 *p_offset = 0;
1099 return NULL;
1100 }
1101
1102 left = 0;
1103 right = p_section->page_count;
1104
1105 // aid in the range [ head aid of pages[left], tail aid of pages[right - 1] ]
1106 while (left < right - 1)
1107 {
1108 // get page id no less than mid value of left page id and right page id
1109 mid = (left + right) / 2 + (right - left) % 2;
1110
1111 if (mid >= p_section->page_count)
1112 {
1113 log_error("page id (mid = %d) is out of boundary\n", mid);
1114 return NULL;
1115 }
1116
1117 if (aid < p_section->p_page_first_article[mid]->aid)
1118 {
1119 right = mid;
1120 }
1121 else
1122 {
1123 left = mid;
1124 }
1125 }
1126
1127 *p_page = left;
1128
1129 p_article = p_section->p_page_first_article[*p_page];
1130
1131 // p_section->p_page_first_article[*p_page]->aid <= aid < p_section->p_page_first_article[*p_page + 1]->aid
1132 right = (*p_page == MAX(0, p_section->page_count - 1) ? INT32_MAX : p_section->p_page_first_article[*p_page + 1]->aid);
1133
1134 // left will be the offset of article found or offset to insert
1135 left = 0;
1136
1137 while (aid > p_article->aid)
1138 {
1139 p_article = p_article->p_next;
1140 left++;
1141
1142 if (aid == p_article->aid)
1143 {
1144 *pp_next = p_article->p_next;
1145 break;
1146 }
1147
1148 // over last article in the page
1149 if (p_article == p_section->p_article_head || p_article->aid >= right)
1150 {
1151 *pp_next = (p_article == p_section->p_article_head ? p_section->p_article_head : p_section->p_page_first_article[*p_page + 1]);
1152 *p_offset = left;
1153 return NULL; // not found
1154 }
1155 }
1156
1157 if (aid < p_article->aid)
1158 {
1159 *pp_next = p_article;
1160 p_article = NULL; // not found
1161 }
1162 else // aid == p_article->aid
1163 {
1164 *pp_next = p_article->p_next;
1165 }
1166
1167 *p_offset = left;
1168
1169 return p_article;
1170 }
1171
1172 int section_list_calculate_page(SECTION_LIST *p_section, int32_t start_aid)
1173 {
1174 ARTICLE *p_article;
1175 ARTICLE *p_next;
1176 int32_t page;
1177 int32_t offset;
1178 int visible_article_count;
1179 int page_head_set;
1180
1181 if (p_section == NULL)
1182 {
1183 log_error("NULL pointer error\n");
1184 return -1;
1185 }
1186
1187 if (p_section->article_count == 0) // empty
1188 {
1189 p_section->page_count = 0;
1190 p_section->last_page_visible_article_count = 0;
1191
1192 return 0;
1193 }
1194
1195 if (start_aid > 0)
1196 {
1197 p_article = article_block_find_by_aid(start_aid);
1198 if (p_article == NULL)
1199 {
1200 return -1; // Not found
1201 }
1202
1203 if (p_section->sid != p_article->sid)
1204 {
1205 log_error("section_list_calculate_page() error: section sid %d != start article sid %d\n", p_section->sid, p_article->sid);
1206 return -2;
1207 }
1208
1209 p_article = section_list_find_article_with_offset(p_section, start_aid, &page, &offset, &p_next);
1210 if (p_article == NULL)
1211 {
1212 if (page < 0)
1213 {
1214 return -1;
1215 }
1216 log_error("section_list_calculate_page() aid = %d not found in section sid = %d\n",
1217 start_aid, p_section->sid);
1218 return -2;
1219 }
1220
1221 if (offset > 0)
1222 {
1223 p_article = p_section->p_page_first_article[page];
1224 }
1225 }
1226 else
1227 {
1228 p_article = p_section->p_article_head;
1229 page = 0;
1230 offset = 0;
1231 }
1232
1233 visible_article_count = 0;
1234 page_head_set = 0;
1235
1236 do
1237 {
1238 if (!page_head_set && visible_article_count == 0)
1239 {
1240 p_section->p_page_first_article[page] = p_article;
1241 page_head_set = 1;
1242 }
1243
1244 if (p_article->visible)
1245 {
1246 visible_article_count++;
1247 }
1248
1249 p_article = p_article->p_next;
1250
1251 // skip remaining invisible articles
1252 while (p_article->visible == 0 && p_article != p_section->p_article_head)
1253 {
1254 p_article = p_article->p_next;
1255 }
1256
1257 if (visible_article_count >= BBS_article_limit_per_page && p_article != p_section->p_article_head)
1258 {
1259 page++;
1260 visible_article_count = 0;
1261 page_head_set = 0;
1262
1263 if (page >= BBS_article_limit_per_section / BBS_article_limit_per_page && p_article != p_section->p_article_head)
1264 {
1265 log_error("Count of page exceed limit in section %d\n", p_section->sid);
1266 break;
1267 }
1268 }
1269 } while (p_article != p_section->p_article_head);
1270
1271 p_section->page_count = page + (visible_article_count > 0 ? 1 : 0);
1272 p_section->last_page_visible_article_count = visible_article_count;
1273
1274 return 0;
1275 }
1276
1277 int32_t article_block_last_aid(void)
1278 {
1279 ARTICLE_BLOCK *p_block = p_article_block_pool->p_block[p_article_block_pool->block_count - 1];
1280 int32_t last_aid = p_block->articles[p_block->article_count - 1].aid;
1281
1282 return last_aid;
1283 }
1284
1285 int article_block_article_count(void)
1286 {
1287 int ret;
1288
1289 if (p_article_block_pool == NULL || p_article_block_pool->block_count <= 0)
1290 {
1291 return -1;
1292 }
1293
1294 ret = (p_article_block_pool->block_count - 1) * ARTICLE_PER_BLOCK +
1295 p_article_block_pool->p_block[p_article_block_pool->block_count - 1]->article_count;
1296
1297 return ret;
1298 }
1299
1300 int article_count_of_topic(int32_t aid)
1301 {
1302 ARTICLE *p_article;
1303 int article_count;
1304
1305 p_article = article_block_find_by_aid(aid);
1306 if (p_article == NULL)
1307 {
1308 return 0; // Not found
1309 }
1310
1311 article_count = 0;
1312
1313 do
1314 {
1315 if (p_article->tid != 0 && p_article->tid != aid)
1316 {
1317 log_error("article_count_of_topic(%d) error: article %d not linked to the topic\n", aid, p_article->aid);
1318 break;
1319 }
1320
1321 article_count++;
1322 p_article = p_article->p_topic_next;
1323 } while (p_article->aid != aid);
1324
1325 return article_count;
1326 }
1327
1328 int section_list_move_topic(SECTION_LIST *p_section_src, SECTION_LIST *p_section_dest, int32_t aid)
1329 {
1330 ARTICLE *p_article;
1331 ARTICLE *p_next;
1332 int32_t page;
1333 int32_t offset;
1334 int32_t move_article_count;
1335 int32_t dest_article_count_old;
1336 int32_t last_unaffected_aid_src;
1337 int32_t first_inserted_aid_dest;
1338 int move_counter;
1339
1340 if (p_section_src == NULL || p_section_dest == NULL)
1341 {
1342 log_error("NULL pointer error\n");
1343 return -1;
1344 }
1345
1346 if (p_section_src->sid == p_section_dest->sid)
1347 {
1348 log_error("section_list_move_topic() src and dest section are the same\n");
1349 return -1;
1350 }
1351
1352 if ((p_article = article_block_find_by_aid(aid)) == NULL)
1353 {
1354 log_error("article_block_find_by_aid(aid = %d) error: article not found\n", aid);
1355 return -2;
1356 }
1357
1358 if (p_section_src->sid != p_article->sid)
1359 {
1360 log_error("section_list_move_topic() error: src section sid %d != article %d sid %d\n",
1361 p_section_src->sid, p_article->aid, p_article->sid);
1362 return -2;
1363 }
1364
1365 if (p_article->tid != 0)
1366 {
1367 log_error("section_list_move_topic(aid = %d) error: article is not head of topic, tid = %d\n", aid, p_article->tid);
1368 return -2;
1369 }
1370
1371 last_unaffected_aid_src = (p_article == p_section_src->p_article_head ? 0 : p_article->p_prior->aid);
1372
1373 move_article_count = article_count_of_topic(aid);
1374 if (move_article_count <= 0)
1375 {
1376 log_error("article_count_of_topic(aid = %d) <= 0\n", aid);
1377 return -2;
1378 }
1379
1380 if (p_section_dest->article_count + move_article_count > BBS_article_limit_per_section)
1381 {
1382 log_error("section_list_move_topic() error: article_count %d reach limit in section %d\n",
1383 p_section_dest->article_count + move_article_count, p_section_dest->sid);
1384 return -3;
1385 }
1386
1387 dest_article_count_old = p_section_dest->article_count;
1388 move_counter = 0;
1389 first_inserted_aid_dest = p_article->aid;
1390
1391 do
1392 {
1393 if (p_section_src->sid != p_article->sid)
1394 {
1395 log_error("section_list_move_topic() warning: src section sid %d != article %d sid %d\n",
1396 p_section_src->sid, p_article->aid, p_article->sid);
1397 p_article = p_article->p_topic_next;
1398 continue;
1399 }
1400
1401 // Remove from bi-directional article list of src section
1402 if (p_section_src->p_article_head == p_article)
1403 {
1404 p_section_src->p_article_head = p_article->p_next;
1405 }
1406 if (p_section_src->p_article_tail == p_article)
1407 {
1408 p_section_src->p_article_tail = p_article->p_prior;
1409 }
1410 if (p_section_src->p_article_head == p_article) // || p_section_src->p_article_tail == p_article
1411 {
1412 p_section_src->p_article_head = NULL;
1413 p_section_src->p_article_tail = NULL;
1414 }
1415
1416 p_article->p_prior->p_next = p_article->p_next;
1417 p_article->p_next->p_prior = p_article->p_prior;
1418
1419 // Update sid of article
1420 p_article->sid = p_section_dest->sid;
1421
1422 if (section_list_find_article_with_offset(p_section_dest, p_article->aid, &page, &offset, &p_next) != NULL)
1423 {
1424 log_error("section_list_move_topic() warning: article %d already in section %d\n", p_article->aid, p_section_dest->sid);
1425 p_article = p_article->p_topic_next;
1426 continue;
1427 }
1428
1429 // Insert into bi-directional article list of dest section
1430 if (p_next == NULL) // empty section
1431 {
1432 p_section_dest->p_article_head = p_article;
1433 p_section_dest->p_article_tail = p_article;
1434 p_article->p_prior = p_article;
1435 p_article->p_next = p_article;
1436 }
1437 else
1438 {
1439 if (p_section_dest->p_article_head == p_next)
1440 {
1441 if (p_article->aid < p_next->aid)
1442 {
1443 p_section_dest->p_article_head = p_article;
1444 }
1445 else // p_article->aid > p_next->aid
1446 {
1447 p_section_dest->p_article_tail = p_article;
1448 }
1449 }
1450
1451 p_article->p_prior = p_next->p_prior;
1452 p_article->p_next = p_next;
1453 p_next->p_prior->p_next = p_article;
1454 p_next->p_prior = p_article;
1455 }
1456
1457 // Update article / topic counter of src / desc section
1458 p_section_src->article_count--;
1459 p_section_dest->article_count++;
1460 if (p_article->tid == 0)
1461 {
1462 p_section_src->topic_count--;
1463 p_section_dest->topic_count++;
1464 }
1465
1466 // Update visible article / topic counter of src / desc section
1467 if (p_article->visible)
1468 {
1469 p_section_src->visible_article_count--;
1470 p_section_dest->visible_article_count++;
1471 if (p_article->tid == 0)
1472 {
1473 p_section_src->visible_topic_count--;
1474 p_section_dest->visible_topic_count++;
1475 }
1476 }
1477
1478 // Update page for empty dest section
1479 if (p_section_dest->article_count == 1)
1480 {
1481 p_section_dest->p_page_first_article[0] = p_article;
1482 p_section_dest->page_count = 1;
1483 p_section_dest->last_page_visible_article_count = (p_article->visible ? 1 : 0);
1484 }
1485
1486 p_article = p_article->p_topic_next;
1487
1488 move_counter++;
1489 if (move_counter % CALCULATE_PAGE_THRESHOLD == 0)
1490 {
1491 // Re-calculate pages of desc section
1492 if (section_list_calculate_page(p_section_dest, first_inserted_aid_dest) < 0)
1493 {
1494 log_error("section_list_calculate_page(dest section = %d, aid = %d) error\n",
1495 p_section_dest->sid, first_inserted_aid_dest);
1496 }
1497
1498 first_inserted_aid_dest = p_article->aid;
1499 }
1500 } while (p_article->aid != aid);
1501
1502 if (p_section_dest->article_count - dest_article_count_old != move_article_count)
1503 {
1504 log_error("section_list_move_topic() warning: count of moved articles %d != %d\n",
1505 p_section_dest->article_count - dest_article_count_old, move_article_count);
1506 }
1507
1508 // Re-calculate pages of src section
1509 if (section_list_calculate_page(p_section_src, last_unaffected_aid_src) < 0)
1510 {
1511 log_error("section_list_calculate_page(src section = %d, aid = %d) error at aid = %d\n",
1512 p_section_src->sid, last_unaffected_aid_src, aid);
1513 }
1514
1515 if (move_counter % CALCULATE_PAGE_THRESHOLD != 0)
1516 {
1517 // Re-calculate pages of desc section
1518 if (section_list_calculate_page(p_section_dest, first_inserted_aid_dest) < 0)
1519 {
1520 log_error("section_list_calculate_page(dest section = %d, aid = %d) error\n",
1521 p_section_dest->sid, first_inserted_aid_dest);
1522 }
1523 }
1524
1525 return move_article_count;
1526 }
1527
1528 int get_section_index(SECTION_LIST *p_section)
1529 {
1530 int index;
1531
1532 if (p_section_list_pool == NULL)
1533 {
1534 log_error("get_section_index() error: uninitialized\n");
1535 return -1;
1536 }
1537
1538 if (p_section == NULL)
1539 {
1540 index = BBS_max_section;
1541 }
1542 else
1543 {
1544 index = (int)(p_section - p_section_list_pool->sections);
1545 if (index < 0 || index >= BBS_max_section)
1546 {
1547 log_error("get_section_index(%d) error: index out of range\n", index);
1548 return -2;
1549 }
1550 }
1551
1552 return index;
1553 }
1554
1555 int section_list_try_rd_lock(SECTION_LIST *p_section, int wait_sec)
1556 {
1557 int index;
1558 struct sembuf sops[4];
1559 struct timespec timeout;
1560 int ret;
1561
1562 index = get_section_index(p_section);
1563 if (index < 0)
1564 {
1565 return -2;
1566 }
1567
1568 sops[0].sem_num = (unsigned short)(index * 2 + 1); // w_sem of section index
1569 sops[0].sem_op = 0; // wait until unlocked
1570 sops[0].sem_flg = 0;
1571
1572 sops[1].sem_num = (unsigned short)(index * 2); // r_sem of section index
1573 sops[1].sem_op = 1; // lock
1574 sops[1].sem_flg = SEM_UNDO; // undo on terminate
1575
1576 // Read lock on any specific section will also acquire single read lock on "all section"
1577 // so that write lock on all section only need to acquire single write on on "all section"
1578 // rather than to acquire multiple write locks on all the available sections.
1579 if (index != BBS_max_section)
1580 {
1581 sops[2].sem_num = BBS_max_section * 2 + 1; // w_sem of all section
1582 sops[2].sem_op = 0; // wait until unlocked
1583 sops[2].sem_flg = 0;
1584
1585 sops[3].sem_num = BBS_max_section * 2; // r_sem of all section
1586 sops[3].sem_op = 1; // lock
1587 sops[3].sem_flg = SEM_UNDO; // undo on terminate
1588 }
1589
1590 timeout.tv_sec = wait_sec;
1591 timeout.tv_nsec = 0;
1592
1593 ret = semtimedop(p_section_list_pool->semid, sops, (index == BBS_max_section ? 2 : 4), &timeout);
1594 if (ret == -1 && errno != EAGAIN && errno != EINTR)
1595 {
1596 log_error("semtimedop(index = %d, lock read) error %d\n", index, errno);
1597 }
1598
1599 return ret;
1600 }
1601
1602 int section_list_try_rw_lock(SECTION_LIST *p_section, int wait_sec)
1603 {
1604 int index;
1605 struct sembuf sops[3];
1606 struct timespec timeout;
1607 int ret;
1608
1609 index = get_section_index(p_section);
1610 if (index < 0)
1611 {
1612 return -2;
1613 }
1614
1615 sops[0].sem_num = (unsigned short)(index * 2 + 1); // w_sem of section index
1616 sops[0].sem_op = 0; // wait until unlocked
1617 sops[0].sem_flg = 0;
1618
1619 sops[1].sem_num = (unsigned short)(index * 2 + 1); // w_sem of section index
1620 sops[1].sem_op = 1; // lock
1621 sops[1].sem_flg = SEM_UNDO; // undo on terminate
1622
1623 sops[2].sem_num = (unsigned short)(index * 2); // r_sem of section index
1624 sops[2].sem_op = 0; // wait until unlocked
1625 sops[2].sem_flg = 0;
1626
1627 timeout.tv_sec = wait_sec;
1628 timeout.tv_nsec = 0;
1629
1630 ret = semtimedop(p_section_list_pool->semid, sops, 3, &timeout);
1631 if (ret == -1 && errno != EAGAIN && errno != EINTR)
1632 {
1633 log_error("semtimedop(index = %d, lock write) error %d\n", index, errno);
1634 }
1635
1636 return ret;
1637 }
1638
1639 int section_list_rd_unlock(SECTION_LIST *p_section)
1640 {
1641 int index;
1642 struct sembuf sops[2];
1643 int ret;
1644
1645 index = get_section_index(p_section);
1646 if (index < 0)
1647 {
1648 return -2;
1649 }
1650
1651 sops[0].sem_num = (unsigned short)(index * 2); // r_sem of section index
1652 sops[0].sem_op = -1; // unlock
1653 sops[0].sem_flg = IPC_NOWAIT | SEM_UNDO; // no wait
1654
1655 if (index != BBS_max_section)
1656 {
1657 sops[1].sem_num = BBS_max_section * 2; // r_sem of all section
1658 sops[1].sem_op = -1; // unlock
1659 sops[1].sem_flg = IPC_NOWAIT | SEM_UNDO; // no wait
1660 }
1661
1662 ret = semop(p_section_list_pool->semid, sops, (index == BBS_max_section ? 1 : 2));
1663 if (ret == -1 && errno != EAGAIN && errno != EINTR)
1664 {
1665 log_error("semop(index = %d, unlock read) error %d\n", index, errno);
1666 }
1667
1668 return ret;
1669 }
1670
1671 int section_list_rw_unlock(SECTION_LIST *p_section)
1672 {
1673 int index;
1674 struct sembuf sops[1];
1675 int ret;
1676
1677 index = get_section_index(p_section);
1678 if (index < 0)
1679 {
1680 return -2;
1681 }
1682
1683 sops[0].sem_num = (unsigned short)(index * 2 + 1); // w_sem of section index
1684 sops[0].sem_op = -1; // unlock
1685 sops[0].sem_flg = IPC_NOWAIT | SEM_UNDO; // no wait
1686
1687 ret = semop(p_section_list_pool->semid, sops, 1);
1688 if (ret == -1 && errno != EAGAIN && errno != EINTR)
1689 {
1690 log_error("semop(index = %d, unlock write) error %d\n", index, errno);
1691 }
1692
1693 return ret;
1694 }
1695
1696 int section_list_rd_lock(SECTION_LIST *p_section)
1697 {
1698 int timer = 0;
1699 int sid = (p_section == NULL ? 0 : p_section->sid);
1700 int ret = -1;
1701
1702 while (!SYS_server_exit)
1703 {
1704 ret = section_list_try_rd_lock(p_section, SECTION_TRY_LOCK_WAIT_TIME);
1705 if (ret == 0) // success
1706 {
1707 break;
1708 }
1709 else if (errno == EAGAIN || errno == EINTR) // retry
1710 {
1711 timer++;
1712 if (timer % SECTION_TRY_LOCK_TIMES == 0)
1713 {
1714 log_error("section_list_try_rd_lock() tried %d times on section %d\n", sid, timer);
1715 }
1716 }
1717 else // failed
1718 {
1719 log_error("section_list_try_rd_lock() failed on section %d\n", sid);
1720 break;
1721 }
1722 }
1723
1724 return ret;
1725 }
1726
1727 int section_list_rw_lock(SECTION_LIST *p_section)
1728 {
1729 int timer = 0;
1730 int sid = (p_section == NULL ? 0 : p_section->sid);
1731 int ret = -1;
1732
1733 while (!SYS_server_exit)
1734 {
1735 ret = section_list_try_rw_lock(p_section, SECTION_TRY_LOCK_WAIT_TIME);
1736 if (ret == 0) // success
1737 {
1738 break;
1739 }
1740 else if (errno == EAGAIN || errno == EINTR) // retry
1741 {
1742 timer++;
1743 if (timer % SECTION_TRY_LOCK_TIMES == 0)
1744 {
1745 log_error("section_list_try_rw_lock() tried %d times on section %d\n", sid, timer);
1746 }
1747 }
1748 else // failed
1749 {
1750 log_error("section_list_try_rw_lock() failed on section %d\n", sid);
1751 break;
1752 }
1753 }
1754
1755 return ret;
1756 }

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