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Revision 1.20 - (show annotations)
Sun May 25 08:15:03 2025 UTC (9 months, 3 weeks ago) by sysadm
Branch: MAIN
Changes since 1.19: +0 -1 lines
Content type: text/x-csrc
Remove debug message

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 #define _GNU_SOURCE
18
19 #include "section_list.h"
20 #include "log.h"
21 #include "trie_dict.h"
22 #include <stdio.h>
23 #include <string.h>
24 #include <signal.h>
25 #include <unistd.h>
26 #include <stdlib.h>
27 #include <errno.h>
28 #include <sys/param.h>
29 #include <sys/sem.h>
30 #include <sys/shm.h>
31 #include <sys/ipc.h>
32
33 #ifdef _SEM_SEMUN_UNDEFINED
34 union semun
35 {
36 int val; /* Value for SETVAL */
37 struct semid_ds *buf; /* Buffer for IPC_STAT, IPC_SET */
38 unsigned short *array; /* Array for GETALL, SETALL */
39 struct seminfo *__buf; /* Buffer for IPC_INFO
40 (Linux-specific) */
41 };
42 #endif // #ifdef _SEM_SEMUN_UNDEFINED
43
44 #define ARTICLE_BLOCK_PER_SHM 400 // sizeof(ARTICLE_BLOCK) * ARTICLE_BLOCK_PER_SHM is the size of each shm segment to allocate
45 #define ARTICLE_BLOCK_SHM_COUNT_LIMIT 200 // limited by length (8-bit) of proj_id in ftok(path, proj_id)
46 #define ARTICLE_BLOCK_PER_POOL (ARTICLE_BLOCK_PER_SHM * ARTICLE_BLOCK_SHM_COUNT_LIMIT)
47
48 #define CALCULATE_PAGE_THRESHOLD 100 // Adjust to tune performance of move topic
49
50 #define SID_STR_LEN 5 // 32-bit + NULL
51
52 struct article_block_t
53 {
54 ARTICLE articles[ARTICLE_PER_BLOCK];
55 int32_t article_count;
56 struct article_block_t *p_next_block;
57 };
58 typedef struct article_block_t ARTICLE_BLOCK;
59
60 struct article_block_shm_t
61 {
62 int shmid;
63 void *p_shm;
64 };
65 typedef struct article_block_shm_t ARTICLE_BLOCK_SHM;
66
67 struct article_block_pool_t
68 {
69 ARTICLE_BLOCK_SHM shm_pool[ARTICLE_BLOCK_SHM_COUNT_LIMIT];
70 int shm_count;
71 ARTICLE_BLOCK *p_block_free_list;
72 ARTICLE_BLOCK *p_block[ARTICLE_BLOCK_PER_POOL];
73 int32_t block_count;
74 };
75 typedef struct article_block_pool_t ARTICLE_BLOCK_POOL;
76
77 static int article_block_pool_shmid;
78 static ARTICLE_BLOCK_POOL *p_article_block_pool = NULL;
79
80 static int section_list_pool_semid;
81 static int section_list_pool_shmid;
82 static SECTION_LIST *p_section_list_pool = NULL;
83
84 static int section_list_count = 0;
85 static TRIE_NODE *p_trie_dict_section_by_name = NULL;
86 static TRIE_NODE *p_trie_dict_section_by_sid = NULL;
87
88 int article_block_init(const char *filename, int block_count)
89 {
90 int shmid;
91 int proj_id;
92 key_t key;
93 size_t size;
94 void *p_shm;
95 int i;
96 int block_count_in_shm;
97 ARTICLE_BLOCK *p_block_in_shm;
98 ARTICLE_BLOCK **pp_block_next;
99
100 if (p_article_block_pool != NULL)
101 {
102 log_error("article_block_pool already initialized\n");
103 return -1;
104 }
105
106 if (block_count > ARTICLE_BLOCK_PER_POOL)
107 {
108 log_error("article_block_count exceed limit %d\n", ARTICLE_BLOCK_PER_POOL);
109 return -2;
110 }
111
112 // Allocate shared memory
113 proj_id = ARTICLE_BLOCK_SHM_COUNT_LIMIT; // keep different from proj_id used to create block shm
114 key = ftok(filename, proj_id);
115 if (key == -1)
116 {
117 log_error("ftok(%s, %d) error (%d)\n", filename, proj_id, errno);
118 return -3;
119 }
120
121 size = sizeof(ARTICLE_BLOCK_POOL);
122 shmid = shmget(key, size, IPC_CREAT | IPC_EXCL | 0600);
123 if (shmid == -1)
124 {
125 log_error("shmget(article_block_pool_shm, size = %d) error (%d)\n", size, errno);
126 return -3;
127 }
128 p_shm = shmat(shmid, NULL, 0);
129 if (p_shm == (void *)-1)
130 {
131 log_error("shmat(shmid = %d) error (%d)\n", shmid, errno);
132 return -3;
133 }
134
135 article_block_pool_shmid = shmid;
136 p_article_block_pool = p_shm;
137
138 p_article_block_pool->shm_count = 0;
139 pp_block_next = &(p_article_block_pool->p_block_free_list);
140
141 while (block_count > 0)
142 {
143 block_count_in_shm = MIN(block_count, ARTICLE_BLOCK_PER_SHM);
144 block_count -= block_count_in_shm;
145
146 proj_id = p_article_block_pool->shm_count;
147 key = ftok(filename, proj_id);
148 if (key == -1)
149 {
150 log_error("ftok(%s, %d) error (%d)\n", filename, proj_id, errno);
151 article_block_cleanup();
152 return -3;
153 }
154
155 size = sizeof(ARTICLE_BLOCK) * (size_t)block_count_in_shm;
156 shmid = shmget(key, size, IPC_CREAT | IPC_EXCL | 0600);
157 if (shmid == -1)
158 {
159 log_error("shmget(shm_index = %d, size = %d) error (%d)\n", p_article_block_pool->shm_count, size, errno);
160 article_block_cleanup();
161 return -3;
162 }
163 p_shm = shmat(shmid, NULL, 0);
164 if (p_shm == (void *)-1)
165 {
166 log_error("shmat(shmid = %d) error (%d)\n", shmid, errno);
167 article_block_cleanup();
168 return -3;
169 }
170
171 (p_article_block_pool->shm_pool + p_article_block_pool->shm_count)->shmid = shmid;
172 (p_article_block_pool->shm_pool + p_article_block_pool->shm_count)->p_shm = p_shm;
173 p_article_block_pool->shm_count++;
174
175 p_block_in_shm = p_shm;
176 *pp_block_next = p_block_in_shm;
177
178 for (i = 0; i < block_count_in_shm; i++)
179 {
180 if (i < block_count_in_shm - 1)
181 {
182 (p_block_in_shm + i)->p_next_block = (p_block_in_shm + i + 1);
183 }
184 else
185 {
186 (p_block_in_shm + i)->p_next_block = NULL;
187 pp_block_next = &((p_block_in_shm + i)->p_next_block);
188 }
189 }
190 }
191
192 p_article_block_pool->block_count = 0;
193
194 return 0;
195 }
196
197 void article_block_cleanup(void)
198 {
199 if (p_article_block_pool == NULL)
200 {
201 return;
202 }
203
204 for (int i = 0; i < p_article_block_pool->shm_count; i++)
205 {
206 if (shmdt((p_article_block_pool->shm_pool + i)->p_shm) == -1)
207 {
208 log_error("shmdt(shmid = %d) error (%d)\n", (p_article_block_pool->shm_pool + i)->shmid, errno);
209 }
210
211 if (shmctl((p_article_block_pool->shm_pool + i)->shmid, IPC_RMID, NULL) == -1)
212 {
213 log_error("shmctl(shmid = %d, IPC_RMID) error (%d)\n", (p_article_block_pool->shm_pool + i)->shmid, errno);
214 }
215 }
216
217 if (shmdt(p_article_block_pool) == -1)
218 {
219 log_error("shmdt(shmid = %d) error (%d)\n", article_block_pool_shmid, errno);
220 }
221
222 if (shmctl(article_block_pool_shmid, IPC_RMID, NULL) == -1)
223 {
224 log_error("shmctl(shmid = %d, IPC_RMID) error (%d)\n", article_block_pool_shmid, errno);
225 }
226
227 p_article_block_pool = NULL;
228 }
229
230 inline static ARTICLE_BLOCK *pop_free_article_block(void)
231 {
232 ARTICLE_BLOCK *p_block = NULL;
233
234 if (p_article_block_pool->p_block_free_list != NULL)
235 {
236 p_block = p_article_block_pool->p_block_free_list;
237 p_article_block_pool->p_block_free_list = p_block->p_next_block;
238 p_block->p_next_block = NULL;
239 p_block->article_count = 0;
240 }
241
242 return p_block;
243 }
244
245 inline static void push_free_article_block(ARTICLE_BLOCK *p_block)
246 {
247 p_block->p_next_block = p_article_block_pool->p_block_free_list;
248 p_article_block_pool->p_block_free_list = p_block;
249 }
250
251 int article_block_reset(void)
252 {
253 ARTICLE_BLOCK *p_block;
254
255 if (p_article_block_pool == NULL)
256 {
257 log_error("article_block_pool not initialized\n");
258 return -1;
259 }
260
261 while (p_article_block_pool->block_count > 0)
262 {
263 p_article_block_pool->block_count--;
264 p_block = p_article_block_pool->p_block[p_article_block_pool->block_count];
265 push_free_article_block(p_block);
266 }
267
268 return 0;
269 }
270
271 ARTICLE *article_block_find_by_aid(int32_t aid)
272 {
273 ARTICLE_BLOCK *p_block;
274 int left;
275 int right;
276 int mid;
277
278 if (p_article_block_pool == NULL)
279 {
280 log_error("article_block_pool not initialized\n");
281 return NULL;
282 }
283
284 if (p_article_block_pool->block_count == 0) // empty
285 {
286 return NULL;
287 }
288
289 left = 0;
290 right = p_article_block_pool->block_count;
291
292 // aid in the range [ head aid of blocks[left], tail aid of blocks[right - 1] ]
293 while (left < right - 1)
294 {
295 // get block offset no less than mid value of left and right block offsets
296 mid = (left + right) / 2 + (right - left) % 2;
297
298 if (mid >= p_article_block_pool->block_count)
299 {
300 log_error("block(mid = %d) is out of boundary\n", mid);
301 return NULL;
302 }
303
304 if (aid < p_article_block_pool->p_block[mid]->articles[0].aid)
305 {
306 right = mid;
307 }
308 else
309 {
310 left = mid;
311 }
312 }
313
314 p_block = p_article_block_pool->p_block[left];
315
316 left = 0;
317 right = p_block->article_count - 1;
318
319 // aid in the range [ aid of articles[left], aid of articles[right] ]
320 while (left < right)
321 {
322 mid = (left + right) / 2;
323
324 if (aid <= p_block->articles[mid].aid)
325 {
326 right = mid;
327 }
328 else
329 {
330 left = mid + 1;
331 }
332 }
333
334 return (p_block->articles + left);
335 }
336
337 ARTICLE *article_block_find_by_index(int index)
338 {
339 ARTICLE_BLOCK *p_block;
340
341 if (p_article_block_pool == NULL)
342 {
343 log_error("article_block_pool not initialized\n");
344 return NULL;
345 }
346
347 if (index < 0 || index / ARTICLE_PER_BLOCK >= p_article_block_pool->block_count)
348 {
349 log_error("article_block_find_by_index(%d) is out of boundary of block [0, %d)\n", index, p_article_block_pool->block_count);
350 return NULL;
351 }
352
353 p_block = p_article_block_pool->p_block[index / ARTICLE_PER_BLOCK];
354
355 if (index % ARTICLE_PER_BLOCK >= p_block->article_count)
356 {
357 log_error("article_block_find_by_index(%d) is out of boundary of article [0, %d)\n", index, p_block->article_count);
358 return NULL;
359 }
360
361 return (p_block->articles + (index % ARTICLE_PER_BLOCK));
362 }
363
364 extern int section_list_init(const char *filename)
365 {
366 int semid;
367 int shmid;
368 int proj_id;
369 key_t key;
370 size_t size;
371 void *p_shm;
372 union semun arg;
373 int i;
374
375 if (p_section_list_pool == NULL || p_trie_dict_section_by_name == NULL || p_trie_dict_section_by_sid == NULL)
376 {
377 section_list_cleanup();
378 }
379
380 proj_id = (int)(time(NULL) % getpid());
381 key = ftok(filename, proj_id);
382 if (key == -1)
383 {
384 log_error("ftok(%s, %d) error (%d)\n", filename, proj_id, errno);
385 return -3;
386 }
387
388 size = 2 * (BBS_max_section + 1); // r_sem and w_sem per section, the last pair for all sections
389 semid = semget(key, (int)size, IPC_CREAT | IPC_EXCL | 0600);
390 if (semid == -1)
391 {
392 log_error("semget(section_list_pool_sem, size = %d) error (%d)\n", size, errno);
393 return -3;
394 }
395
396 // Initialize sem value to 0
397 arg.val = 0;
398 for (i = 0; i < size; i++)
399 {
400 if (semctl(semid, i, SETVAL, arg) == -1)
401 {
402 log_error("semctl(section_list_pool_sem, SETVAL) error (%d)\n", errno);
403 return -3;
404 }
405 }
406
407 section_list_pool_semid = semid;
408
409 size = sizeof(SECTION_LIST) * BBS_max_section;
410 shmid = shmget(key, size, IPC_CREAT | IPC_EXCL | 0600);
411 if (shmid == -1)
412 {
413 log_error("shmget(section_list_pool_shm, size = %d) error (%d)\n", size, errno);
414 return -3;
415 }
416 p_shm = shmat(shmid, NULL, 0);
417 if (p_shm == (void *)-1)
418 {
419 log_error("shmat(shmid = %d) error (%d)\n", shmid, errno);
420 return -3;
421 }
422
423 section_list_pool_shmid = shmid;
424 p_section_list_pool = p_shm;
425 section_list_count = 0;
426
427 p_trie_dict_section_by_name = trie_dict_create();
428 if (p_trie_dict_section_by_name == NULL)
429 {
430 log_error("trie_dict_create() OOM\n", BBS_max_section);
431 return -2;
432 }
433
434 p_trie_dict_section_by_sid = trie_dict_create();
435 if (p_trie_dict_section_by_sid == NULL)
436 {
437 log_error("trie_dict_create() OOM\n", BBS_max_section);
438 return -2;
439 }
440
441 return 0;
442 }
443
444 inline static void sid_to_str(int32_t sid, char *p_sid_str)
445 {
446 uint32_t u_sid;
447 int i;
448
449 u_sid = (uint32_t)sid;
450 for (i = 0; i < SID_STR_LEN - 1; i++)
451 {
452 p_sid_str[i] = (char)(u_sid % 255 + 1);
453 u_sid /= 255;
454 }
455 p_sid_str[i] = '\0';
456 }
457
458 SECTION_LIST *section_list_create(int32_t sid, const char *sname, const char *stitle, const char *master_name)
459 {
460 SECTION_LIST *p_section;
461 char sid_str[SID_STR_LEN];
462
463 if (p_section_list_pool == NULL || p_trie_dict_section_by_name == NULL || p_trie_dict_section_by_sid == NULL)
464 {
465 log_error("session_list_pool not initialized\n");
466 return NULL;
467 }
468
469 if (section_list_count >= BBS_max_section)
470 {
471 log_error("section_list_count exceed limit %d >= %d\n", section_list_count, BBS_max_section);
472 return NULL;
473 }
474
475 sid_to_str(sid, sid_str);
476
477 p_section = p_section_list_pool + section_list_count;
478
479 p_section->sid = sid;
480
481 strncpy(p_section->sname, sname, sizeof(p_section->sname - 1));
482 p_section->sname[sizeof(p_section->sname - 1)] = '\0';
483
484 strncpy(p_section->stitle, stitle, sizeof(p_section->stitle - 1));
485 p_section->stitle[sizeof(p_section->stitle - 1)] = '\0';
486
487 strncpy(p_section->master_name, master_name, sizeof(p_section->master_name - 1));
488 p_section->master_name[sizeof(p_section->master_name - 1)] = '\0';
489
490 if (trie_dict_set(p_trie_dict_section_by_name, sname, section_list_count) != 1)
491 {
492 log_error("trie_dict_set(section, %s, %d) error\n", sname, section_list_count);
493 return NULL;
494 }
495
496 if (trie_dict_set(p_trie_dict_section_by_sid, sid_str, section_list_count) != 1)
497 {
498 log_error("trie_dict_set(section, %d, %d) error\n", sid, section_list_count);
499 return NULL;
500 }
501
502 section_list_reset_articles(p_section);
503
504 section_list_count++;
505
506 return p_section;
507 }
508
509 void section_list_reset_articles(SECTION_LIST *p_section)
510 {
511 p_section->article_count = 0;
512 p_section->topic_count = 0;
513 p_section->visible_article_count = 0;
514 p_section->visible_topic_count = 0;
515 p_section->p_article_head = NULL;
516 p_section->p_article_tail = NULL;
517
518 p_section->page_count = 0;
519 p_section->last_page_visible_article_count = 0;
520 }
521
522 void section_list_cleanup(void)
523 {
524 if (p_trie_dict_section_by_name != NULL)
525 {
526 trie_dict_destroy(p_trie_dict_section_by_name);
527 p_trie_dict_section_by_name = NULL;
528 }
529
530 if (p_trie_dict_section_by_sid != NULL)
531 {
532 trie_dict_destroy(p_trie_dict_section_by_sid);
533 p_trie_dict_section_by_sid = NULL;
534 }
535
536 if (p_section_list_pool != NULL)
537 {
538 if (shmdt(p_section_list_pool) == -1)
539 {
540 log_error("shmdt(shmid = %d) error (%d)\n", section_list_pool_shmid, errno);
541 }
542 p_section_list_pool = NULL;
543
544 if (shmctl(section_list_pool_shmid, IPC_RMID, NULL) == -1)
545 {
546 log_error("shmctl(shmid = %d, IPC_RMID) error (%d)\n", section_list_pool_shmid, errno);
547 }
548
549 if (semctl(section_list_pool_semid, 0, IPC_RMID) == -1)
550 {
551 log_error("semctl(semid = %d, IPC_RMID) error (%d)\n", section_list_pool_semid, errno);
552 }
553 }
554
555 section_list_count = 0;
556 }
557
558 SECTION_LIST *section_list_find_by_name(const char *sname)
559 {
560 int64_t index;
561
562 if (p_section_list_pool == NULL || p_trie_dict_section_by_name == NULL)
563 {
564 log_error("section_list not initialized\n");
565 return NULL;
566 }
567
568 if (trie_dict_get(p_trie_dict_section_by_name, sname, &index) != 1)
569 {
570 log_error("trie_dict_get(section, %s) error\n", sname);
571 return NULL;
572 }
573
574 return (p_section_list_pool + index);
575 }
576
577 SECTION_LIST *section_list_find_by_sid(int32_t sid)
578 {
579 int64_t index;
580 char sid_str[SID_STR_LEN];
581
582 if (p_section_list_pool == NULL || p_trie_dict_section_by_sid == NULL)
583 {
584 log_error("section_list not initialized\n");
585 return NULL;
586 }
587
588 sid_to_str(sid, sid_str);
589
590 if (trie_dict_get(p_trie_dict_section_by_sid, sid_str, &index) != 1)
591 {
592 log_error("trie_dict_get(section, %d) error\n", sid);
593 return NULL;
594 }
595
596 return (p_section_list_pool + index);
597 }
598
599 int section_list_append_article(SECTION_LIST *p_section, const ARTICLE *p_article_src)
600 {
601 ARTICLE_BLOCK *p_block;
602 int32_t last_aid = 0;
603 ARTICLE *p_article;
604 ARTICLE *p_topic_head;
605 ARTICLE *p_topic_tail;
606
607 if (p_section == NULL || p_article_src == NULL)
608 {
609 log_error("section_list_append_article() NULL pointer error\n");
610 return -1;
611 }
612
613 if (p_article_block_pool == NULL)
614 {
615 log_error("article_block_pool not initialized\n");
616 return -1;
617 }
618
619 if (p_section->sid != p_article_src->sid)
620 {
621 log_error("section_list_append_article() error: section sid %d != article sid %d\n", p_section->sid, p_article_src->sid);
622 return -2;
623 }
624
625 if (p_section->article_count >= BBS_article_limit_per_section)
626 {
627 log_error("section_list_append_article() error: article_count reach limit in section %d\n", p_section->sid);
628 return -2;
629 }
630
631 if (p_article_block_pool->block_count == 0 ||
632 p_article_block_pool->p_block[p_article_block_pool->block_count - 1]->article_count >= ARTICLE_PER_BLOCK)
633 {
634 if ((p_block = pop_free_article_block()) == NULL)
635 {
636 log_error("pop_free_article_block() error\n");
637 return -2;
638 }
639
640 if (p_article_block_pool->block_count > 0)
641 {
642 last_aid = p_article_block_pool->p_block[p_article_block_pool->block_count - 1]->articles[ARTICLE_PER_BLOCK - 1].aid;
643 }
644
645 p_article_block_pool->p_block[p_article_block_pool->block_count] = p_block;
646 p_article_block_pool->block_count++;
647 }
648 else
649 {
650 p_block = p_article_block_pool->p_block[p_article_block_pool->block_count - 1];
651 last_aid = p_block->articles[p_block->article_count - 1].aid;
652 }
653
654 // AID of articles should be strictly ascending
655 if (p_article_src->aid <= last_aid)
656 {
657 log_error("section_list_append_article(aid=%d) error: last_aid=%d\n", p_article_src->aid, last_aid);
658 return -3;
659 }
660
661 p_article = (p_block->articles + p_block->article_count);
662 p_block->article_count++;
663 p_section->article_count++;
664
665 // Copy article data
666 *p_article = *p_article_src;
667
668 if (p_article->visible)
669 {
670 p_section->visible_article_count++;
671 }
672
673 // Link appended article as tail node of topic bi-directional list
674 if (p_article->tid != 0)
675 {
676 p_topic_head = article_block_find_by_aid(p_article->tid);
677 if (p_topic_head == NULL)
678 {
679 log_error("search head of topic (aid=%d) error\n", p_article->tid);
680 return -4;
681 }
682
683 p_topic_tail = p_topic_head->p_topic_prior;
684 if (p_topic_tail == NULL)
685 {
686 log_error("tail of topic (aid=%d) is NULL\n", p_article->tid);
687 return -4;
688 }
689 }
690 else
691 {
692 p_section->topic_count++;
693
694 if (p_article->visible)
695 {
696 p_section->visible_topic_count++;
697 }
698
699 p_topic_head = p_article;
700 p_topic_tail = p_article;
701 }
702
703 p_article->p_topic_prior = p_topic_tail;
704 p_article->p_topic_next = p_topic_head;
705 p_topic_head->p_topic_prior = p_article;
706 p_topic_tail->p_topic_next = p_article;
707
708 // Link appended article as tail node of article bi-directional list
709 if (p_section->p_article_head == NULL)
710 {
711 p_section->p_article_head = p_article;
712 p_section->p_article_tail = p_article;
713 }
714 p_article->p_prior = p_section->p_article_tail;
715 p_article->p_next = p_section->p_article_head;
716 p_section->p_article_head->p_prior = p_article;
717 p_section->p_article_tail->p_next = p_article;
718 p_section->p_article_tail = p_article;
719
720 // Update page
721 if ((p_article->visible && p_section->last_page_visible_article_count % BBS_article_limit_per_page == 0) ||
722 p_section->article_count == 1)
723 {
724 p_section->p_page_first_article[p_section->page_count] = p_article;
725 p_section->page_count++;
726 p_section->last_page_visible_article_count = 0;
727 }
728
729 if (p_article->visible)
730 {
731 p_section->last_page_visible_article_count++;
732 }
733
734 return 0;
735 }
736
737 int section_list_set_article_visible(SECTION_LIST *p_section, int32_t aid, int8_t visible)
738 {
739 ARTICLE *p_article;
740 ARTICLE *p_reply;
741 int affected_count = 0;
742
743 if (p_section == NULL)
744 {
745 log_error("section_list_set_article_visible() NULL pointer error\n");
746 return -2;
747 }
748
749 p_article = article_block_find_by_aid(aid);
750 if (p_article == NULL)
751 {
752 return -1; // Not found
753 }
754
755 if (p_section->sid != p_article->sid)
756 {
757 log_error("section_list_set_article_visible() error: section sid %d != article sid %d\n", p_section->sid, p_article->sid);
758 return -2;
759 }
760
761 if (p_article->visible == visible)
762 {
763 return 0; // Already set
764 }
765
766 if (visible == 0) // 1 -> 0
767 {
768 p_section->visible_article_count--;
769
770 if (p_article->tid == 0)
771 {
772 p_section->visible_topic_count--;
773
774 // Set related visible replies to invisible
775 for (p_reply = p_article->p_topic_next; p_reply->tid != 0; p_reply = p_reply->p_topic_next)
776 {
777 if (p_reply->tid != aid)
778 {
779 log_error("Inconsistent tid = %d found in reply %d of topic %d\n", p_reply->tid, p_reply->aid, aid);
780 continue;
781 }
782
783 if (p_reply->visible == 1)
784 {
785 p_reply->visible = 0;
786 p_section->visible_article_count--;
787 affected_count++;
788 }
789 }
790 }
791 }
792 else // 0 -> 1
793 {
794 p_section->visible_article_count++;
795
796 if (p_article->tid == 0)
797 {
798 p_section->visible_topic_count++;
799 }
800 }
801
802 p_article->visible = visible;
803 affected_count++;
804
805 return affected_count;
806 }
807
808 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)
809 {
810 ARTICLE *p_article;
811 int left;
812 int right;
813 int mid;
814
815 *p_page = -1;
816 *p_offset = -1;
817 *pp_next = NULL;
818
819 if (p_section == NULL)
820 {
821 log_error("section_list_find_article_with_offset() NULL pointer error\n");
822 return NULL;
823 }
824
825 if (p_section->article_count == 0) // empty
826 {
827 *p_page = 0;
828 *p_offset = 0;
829 return NULL;
830 }
831
832 left = 0;
833 right = p_section->page_count;
834
835 // aid in the range [ head aid of pages[left], tail aid of pages[right - 1] ]
836 while (left < right - 1)
837 {
838 // get page id no less than mid value of left page id and right page id
839 mid = (left + right) / 2 + (right - left) % 2;
840
841 if (mid >= p_section->page_count)
842 {
843 log_error("page id (mid = %d) is out of boundary\n", mid);
844 return NULL;
845 }
846
847 if (aid < p_section->p_page_first_article[mid]->aid)
848 {
849 right = mid;
850 }
851 else
852 {
853 left = mid;
854 }
855 }
856
857 *p_page = left;
858
859 p_article = p_section->p_page_first_article[*p_page];
860
861 // p_section->p_page_first_article[*p_page]->aid <= aid < p_section->p_page_first_article[*p_page + 1]->aid
862 right = (*p_page == MAX(0, p_section->page_count - 1) ? INT32_MAX : p_section->p_page_first_article[*p_page + 1]->aid);
863
864 // left will be the offset of article found or offset to insert
865 left = 0;
866
867 while (aid > p_article->aid)
868 {
869 p_article = p_article->p_next;
870 left++;
871
872 if (aid == p_article->aid)
873 {
874 *pp_next = p_article->p_next;
875 break;
876 }
877
878 // over last article in the page
879 if (p_article == p_section->p_article_head || p_article->aid >= right)
880 {
881 *pp_next = (p_article == p_section->p_article_head ? p_section->p_article_head : p_section->p_page_first_article[*p_page + 1]);
882 *p_offset = left;
883 return NULL; // not found
884 }
885 }
886
887 if (aid < p_article->aid)
888 {
889 *pp_next = p_article;
890 p_article = NULL; // not found
891 }
892 else // aid == p_article->aid
893 {
894 *pp_next = p_article->p_next;
895 }
896
897 *p_offset = left;
898
899 return p_article;
900 }
901
902 int section_list_calculate_page(SECTION_LIST *p_section, int32_t start_aid)
903 {
904 ARTICLE *p_article;
905 ARTICLE *p_next;
906 int32_t page;
907 int32_t offset;
908 int visible_article_count;
909 int page_head_set;
910
911 if (p_section == NULL)
912 {
913 log_error("section_list_calculate_page() NULL pointer error\n");
914 return -1;
915 }
916
917 if (p_section->article_count == 0) // empty
918 {
919 p_section->page_count = 0;
920 p_section->last_page_visible_article_count = 0;
921
922 return 0;
923 }
924
925 if (start_aid > 0)
926 {
927 p_article = article_block_find_by_aid(start_aid);
928 if (p_article == NULL)
929 {
930 return -1; // Not found
931 }
932
933 if (p_section->sid != p_article->sid)
934 {
935 log_error("section_list_calculate_page() error: section sid %d != start article sid %d\n", p_section->sid, p_article->sid);
936 return -2;
937 }
938
939 p_article = section_list_find_article_with_offset(p_section, start_aid, &page, &offset, &p_next);
940 if (p_article == NULL)
941 {
942 if (page < 0)
943 {
944 return -1;
945 }
946 log_error("section_list_calculate_page() aid = %d not found in section sid = %d\n",
947 start_aid, p_section->sid);
948 return -2;
949 }
950
951 if (offset > 0)
952 {
953 p_article = p_section->p_page_first_article[page];
954 }
955 }
956 else
957 {
958 p_article = p_section->p_article_head;
959 page = 0;
960 offset = 0;
961 }
962
963 visible_article_count = 0;
964 page_head_set = 0;
965
966 do
967 {
968 if (!page_head_set && visible_article_count == 0)
969 {
970 p_section->p_page_first_article[page] = p_article;
971 page_head_set = 1;
972 }
973
974 if (p_article->visible)
975 {
976 visible_article_count++;
977 }
978
979 p_article = p_article->p_next;
980
981 // skip remaining invisible articles
982 while (p_article->visible == 0 && p_article != p_section->p_article_head)
983 {
984 p_article = p_article->p_next;
985 }
986
987 if (visible_article_count >= BBS_article_limit_per_page && p_article != p_section->p_article_head)
988 {
989 page++;
990 visible_article_count = 0;
991 page_head_set = 0;
992
993 if (page >= BBS_article_limit_per_section / BBS_article_limit_per_page && p_article != p_section->p_article_head)
994 {
995 log_error("Count of page exceed limit in section %d\n", p_section->sid);
996 break;
997 }
998 }
999 } while (p_article != p_section->p_article_head);
1000
1001 p_section->page_count = page + (visible_article_count > 0 ? 1 : 0);
1002 p_section->last_page_visible_article_count = visible_article_count;
1003
1004 return 0;
1005 }
1006
1007 int article_count_of_topic(int32_t aid)
1008 {
1009 ARTICLE *p_article;
1010 int article_count;
1011
1012 p_article = article_block_find_by_aid(aid);
1013 if (p_article == NULL)
1014 {
1015 return 0; // Not found
1016 }
1017
1018 article_count = 0;
1019
1020 do
1021 {
1022 if (p_article->tid != 0 && p_article->tid != aid)
1023 {
1024 log_error("article_count_of_topic(%d) error: article %d not linked to the topic\n", aid, p_article->aid);
1025 break;
1026 }
1027
1028 article_count++;
1029 p_article = p_article->p_topic_next;
1030 } while (p_article->aid != aid);
1031
1032 return article_count;
1033 }
1034
1035 int section_list_move_topic(SECTION_LIST *p_section_src, SECTION_LIST *p_section_dest, int32_t aid)
1036 {
1037 ARTICLE *p_article;
1038 ARTICLE *p_next;
1039 int32_t page;
1040 int32_t offset;
1041 int32_t move_article_count;
1042 int32_t dest_article_count_old;
1043 int32_t last_unaffected_aid_src;
1044 int32_t first_inserted_aid_dest;
1045 int move_counter;
1046
1047 if (p_section_dest == NULL)
1048 {
1049 log_error("section_list_move_topic() NULL pointer error\n");
1050 return -1;
1051 }
1052
1053 if ((p_article = article_block_find_by_aid(aid)) == NULL)
1054 {
1055 log_error("section_list_move_topic() error: article %d not found in block\n", aid);
1056 return -2;
1057 }
1058
1059 if (p_section_src->sid != p_article->sid)
1060 {
1061 log_error("section_list_move_topic() error: src section sid %d != article %d sid %d\n",
1062 p_section_src->sid, p_article->aid, p_article->sid);
1063 return -2;
1064 }
1065
1066 if (p_article->tid != 0)
1067 {
1068 log_error("section_list_move_topic(aid = %d) error: article is not head of topic, tid = %d\n", aid, p_article->tid);
1069 return -2;
1070 }
1071
1072 last_unaffected_aid_src = (p_article == p_section_src->p_article_head ? 0 : p_article->p_prior->aid);
1073
1074 move_article_count = article_count_of_topic(aid);
1075 if (move_article_count <= 0)
1076 {
1077 log_error("section_list_count_of_topic_articles(aid = %d) <= 0\n", aid);
1078 return -2;
1079 }
1080
1081 if (p_section_dest->article_count + move_article_count > BBS_article_limit_per_section)
1082 {
1083 log_error("section_list_move_topic() error: article_count %d reach limit in section %d\n",
1084 p_section_dest->article_count + move_article_count, p_section_dest->sid);
1085 return -3;
1086 }
1087
1088 dest_article_count_old = p_section_dest->article_count;
1089 move_counter = 0;
1090 first_inserted_aid_dest = p_article->aid;
1091
1092 do
1093 {
1094 if (p_section_src->sid != p_article->sid)
1095 {
1096 log_error("section_list_move_topic() error: src section sid %d != article %d sid %d\n",
1097 p_section_src->sid, p_article->aid, p_article->sid);
1098 return -2;
1099 }
1100
1101 // Remove from bi-directional article list of src section
1102 if (p_section_src->p_article_head == p_article)
1103 {
1104 p_section_src->p_article_head = p_article->p_next;
1105 }
1106 if (p_section_src->p_article_tail == p_article)
1107 {
1108 p_section_src->p_article_tail = p_article->p_prior;
1109 }
1110 if (p_section_src->p_article_head == p_article) // || p_section_src->p_article_tail == p_article
1111 {
1112 p_section_src->p_article_head = NULL;
1113 p_section_src->p_article_tail = NULL;
1114 }
1115
1116 p_article->p_prior->p_next = p_article->p_next;
1117 p_article->p_next->p_prior = p_article->p_prior;
1118
1119 // Update sid of article
1120 p_article->sid = p_section_dest->sid;
1121
1122 if (section_list_find_article_with_offset(p_section_dest, p_article->aid, &page, &offset, &p_next) != NULL)
1123 {
1124 log_error("section_list_move_topic() error: article %d already in section %d\n", p_article->aid, p_section_dest->sid);
1125 return -4;
1126 }
1127
1128 // Insert into bi-directional article list of dest section
1129 if (p_next == NULL) // empty section
1130 {
1131 p_section_dest->p_article_head = p_article;
1132 p_section_dest->p_article_tail = p_article;
1133 p_article->p_prior = p_article;
1134 p_article->p_next = p_article;
1135 }
1136 else
1137 {
1138 if (p_section_dest->p_article_head == p_next)
1139 {
1140 if (p_article->aid < p_next->aid)
1141 {
1142 p_section_dest->p_article_head = p_article;
1143 }
1144 else // p_article->aid > p_next->aid
1145 {
1146 p_section_dest->p_article_tail = p_article;
1147 }
1148 }
1149
1150 p_article->p_prior = p_next->p_prior;
1151 p_article->p_next = p_next;
1152 p_next->p_prior->p_next = p_article;
1153 p_next->p_prior = p_article;
1154 }
1155
1156 // Update article / topic counter of src / desc section
1157 p_section_src->article_count--;
1158 p_section_dest->article_count++;
1159 if (p_article->tid == 0)
1160 {
1161 p_section_src->topic_count--;
1162 p_section_dest->topic_count++;
1163 }
1164
1165 // Update visible article / topic counter of src / desc section
1166 if (p_article->visible)
1167 {
1168 p_section_src->visible_article_count--;
1169 p_section_dest->visible_article_count++;
1170 if (p_article->tid == 0)
1171 {
1172 p_section_src->visible_topic_count--;
1173 p_section_dest->visible_topic_count++;
1174 }
1175 }
1176
1177 // Update page for empty dest section
1178 if (p_section_dest->article_count == 1)
1179 {
1180 p_section_dest->p_page_first_article[0] = p_article;
1181 p_section_dest->page_count = 1;
1182 p_section_dest->last_page_visible_article_count = (p_article->visible ? 1 : 0);
1183 }
1184
1185 p_article = p_article->p_topic_next;
1186
1187 move_counter++;
1188 if (move_counter % CALCULATE_PAGE_THRESHOLD == 0)
1189 {
1190 // Re-calculate pages of desc section
1191 if (section_list_calculate_page(p_section_dest, first_inserted_aid_dest) < 0)
1192 {
1193 log_error("section_list_calculate_page(dest section = %d, aid = %d) error\n",
1194 p_section_dest->sid, first_inserted_aid_dest);
1195 }
1196
1197 first_inserted_aid_dest = p_article->aid;
1198 }
1199 } while (p_article->aid != aid);
1200
1201 if (p_section_dest->article_count - dest_article_count_old != move_article_count)
1202 {
1203 log_error("section_list_move_topic() error: count of moved articles %d != %d\n",
1204 p_section_dest->article_count - dest_article_count_old, move_article_count);
1205 }
1206
1207 // Re-calculate pages of src section
1208 if (section_list_calculate_page(p_section_src, last_unaffected_aid_src) < 0)
1209 {
1210 log_error("section_list_calculate_page(src section = %d, aid = %d) error at aid = %d\n",
1211 p_section_src->sid, last_unaffected_aid_src, aid);
1212 }
1213
1214 if (move_counter % CALCULATE_PAGE_THRESHOLD != 0)
1215 {
1216 // Re-calculate pages of desc section
1217 if (section_list_calculate_page(p_section_dest, first_inserted_aid_dest) < 0)
1218 {
1219 log_error("section_list_calculate_page(dest section = %d, aid = %d) error\n",
1220 p_section_dest->sid, first_inserted_aid_dest);
1221 }
1222 }
1223
1224 return move_article_count;
1225 }
1226
1227 int get_section_index(SECTION_LIST *p_section)
1228 {
1229 int index;
1230
1231 if (p_section_list_pool == NULL)
1232 {
1233 log_error("get_section_index() error: uninitialized\n");
1234 return -1;
1235 }
1236
1237 if (p_section == NULL)
1238 {
1239 index = BBS_max_section;
1240 }
1241 else
1242 {
1243 index = (int)(p_section - p_section_list_pool);
1244 if (index < 0 || index >= BBS_max_section)
1245 {
1246 log_error("get_section_index(%d) error: index out of range\n", index);
1247 return -2;
1248 }
1249 }
1250
1251 return index;
1252 }
1253
1254 int section_list_try_rd_lock(SECTION_LIST *p_section, int wait_sec)
1255 {
1256 int index;
1257 struct sembuf sops[4];
1258 struct timespec timeout;
1259 int ret;
1260
1261 index = get_section_index(p_section);
1262 if (index < 0)
1263 {
1264 return -2;
1265 }
1266
1267 sops[0].sem_num = (unsigned short)(index * 2 + 1); // w_sem of section index
1268 sops[0].sem_op = 0; // wait until unlocked
1269 sops[0].sem_flg = 0;
1270
1271 sops[1].sem_num = (unsigned short)(index * 2); // r_sem of section index
1272 sops[1].sem_op = 1; // lock
1273 sops[1].sem_flg = SEM_UNDO; // undo on terminate
1274
1275 // Read lock on any specific section will also acquire single read lock on "all section"
1276 // so that write lock on all section only need to acquire single write on on "all section"
1277 // rather than to acquire multiple write locks on all the available sections.
1278 if (index == BBS_max_section)
1279 {
1280 sops[2].sem_num = BBS_max_section * 2 + 1; // w_sem of all section
1281 sops[2].sem_op = 0; // wait until unlocked
1282 sops[2].sem_flg = 0;
1283
1284 sops[3].sem_num = BBS_max_section * 2; // r_sem of all section
1285 sops[3].sem_op = 1; // lock
1286 sops[3].sem_flg = SEM_UNDO; // undo on terminate
1287 }
1288
1289 timeout.tv_sec = wait_sec;
1290 timeout.tv_nsec = 0;
1291
1292 ret = semtimedop(section_list_pool_semid, sops, (index == BBS_max_section ? 4 : 2), &timeout);
1293 if (ret == -1 && errno != EAGAIN && errno != EINTR)
1294 {
1295 log_error("semtimedop(index = %d, lock read) error %d\n", index, errno);
1296 }
1297
1298 return ret;
1299 }
1300
1301 int section_list_try_rw_lock(SECTION_LIST *p_section, int wait_sec)
1302 {
1303 int index;
1304 struct sembuf sops[3];
1305 struct timespec timeout;
1306 int ret;
1307
1308 index = get_section_index(p_section);
1309 if (index < 0)
1310 {
1311 return -2;
1312 }
1313
1314 sops[0].sem_num = (unsigned short)(index * 2 + 1); // w_sem of section index
1315 sops[0].sem_op = 0; // wait until unlocked
1316 sops[0].sem_flg = 0;
1317
1318 sops[1].sem_num = (unsigned short)(index * 2 + 1); // w_sem of section index
1319 sops[1].sem_op = 1; // lock
1320 sops[1].sem_flg = SEM_UNDO; // undo on terminate
1321
1322 sops[2].sem_num = (unsigned short)(index * 2); // r_sem of section index
1323 sops[2].sem_op = 0; // wait until unlocked
1324 sops[2].sem_flg = 0;
1325
1326 timeout.tv_sec = wait_sec;
1327 timeout.tv_nsec = 0;
1328
1329 ret = semtimedop(section_list_pool_semid, sops, 3, &timeout);
1330 if (ret == -1 && errno != EAGAIN && errno != EINTR)
1331 {
1332 log_error("semtimedop(index = %d, lock write) error %d\n", index, errno);
1333 }
1334
1335 return ret;
1336 }
1337
1338 int section_list_rd_unlock(SECTION_LIST *p_section)
1339 {
1340 int index;
1341 struct sembuf sops[2];
1342 int ret;
1343
1344 index = get_section_index(p_section);
1345 if (index < 0)
1346 {
1347 return -2;
1348 }
1349
1350 sops[0].sem_num = (unsigned short)(index * 2); // r_sem of section index
1351 sops[0].sem_op = -1; // unlock
1352 sops[0].sem_flg = IPC_NOWAIT | SEM_UNDO; // no wait
1353
1354 // The same reason as section_list_try_rd_lock()
1355 if (index == BBS_max_section)
1356 {
1357 sops[1].sem_num = BBS_max_section * 2; // r_sem of all section
1358 sops[1].sem_op = -1; // unlock
1359 sops[1].sem_flg = IPC_NOWAIT | SEM_UNDO; // no wait
1360 }
1361
1362 ret = semop(section_list_pool_semid, sops, (index == BBS_max_section ? 2 : 1));
1363 if (ret == -1 && errno != EAGAIN && errno != EINTR)
1364 {
1365 log_error("semop(index = %d, unlock read) error %d\n", index, errno);
1366 }
1367
1368 return ret;
1369 }
1370
1371 int section_list_rw_unlock(SECTION_LIST *p_section)
1372 {
1373 int index;
1374 struct sembuf sops[1];
1375 int ret;
1376
1377 index = get_section_index(p_section);
1378 if (index < 0)
1379 {
1380 return -2;
1381 }
1382
1383 sops[0].sem_num = (unsigned short)(index * 2 + 1); // w_sem of section index
1384 sops[0].sem_op = -1; // unlock
1385 sops[0].sem_flg = IPC_NOWAIT | SEM_UNDO; // no wait
1386
1387 ret = semop(section_list_pool_semid, sops, 1);
1388 if (ret == -1 && errno != EAGAIN && errno != EINTR)
1389 {
1390 log_error("semop(index = %d, unlock write) error %d\n", index, errno);
1391 }
1392
1393 return ret;
1394 }

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