Merge branch 't/configure_fix'
[paraslash.git] / mood.c
1 /*
2 * Copyright (C) 2007-2012 Andre Noll <maan@systemlinux.org>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7 /** \file mood.c Paraslash's mood handling functions. */
8
9 #include <regex.h>
10 #include <osl.h>
11
12 #include "para.h"
13 #include "error.h"
14 #include "string.h"
15 #include "afh.h"
16 #include "afs.h"
17 #include "list.h"
18 #include "ipc.h"
19 #include "mm.h"
20
21 /**
22 * Contains statistical data of the currently admissible audio files.
23 *
24 * It is used to assign normalized score values to each admissible audio file.
25 */
26 struct afs_statistics {
27 /** Sum of num played over all admissible files. */
28 int64_t num_played_sum;
29 /** Sum of last played times over all admissible files. */
30 int64_t last_played_sum;
31 /** Quadratic deviation of num played time. */
32 int64_t num_played_qd;
33 /** Quadratic deviation of last played time. */
34 int64_t last_played_qd;
35 /** Number of admissible files */
36 unsigned num;
37 };
38 static struct afs_statistics statistics;
39
40 /**
41 * Each line of the current mood corresponds to a mood_item.
42 */
43 struct mood_item {
44 /** The method this line is referring to. */
45 const struct mood_method *method;
46 /** The data structure computed by the mood parser. */
47 void *parser_data;
48 /** The given score value, or zero if none was given. */
49 int32_t score_arg;
50 /** Non-zero if random scoring was requested. */
51 int random_score;
52 /** Whether the "not" keyword was given in the mood line. */
53 int logical_not;
54 /** The position in the list of items. */
55 struct list_head mood_item_node;
56 };
57
58 /**
59 * Created from the mood definition by mood_open().
60 *
61 * When a mood is opened, each line of its definition is investigated, and a
62 * corresponding mood item is produced. Each mood line starts with \p accept,
63 * \p deny, or \p score which determines the type of the mood line. For each
64 * such type a linked list is maintained whose entries are the mood items.
65 *
66 * \sa mood_item, mood_open().
67 */
68 struct mood {
69 /** The name of this mood. */
70 char *name;
71 /** The list of mood items of type \p accept. */
72 struct list_head accept_list;
73 /** The list of mood items of type \p deny. */
74 struct list_head deny_list;
75 /** The list of mood items of type \p score. */
76 struct list_head score_list;
77 };
78
79 static struct mood *current_mood;
80
81 /**
82 * Rough approximation to sqrt.
83 *
84 * \param x Integer of which to calculate the sqrt.
85 *
86 * \return An integer res with res * res <= x.
87 */
88 __a_const static uint64_t int_sqrt(uint64_t x)
89 {
90 uint64_t op, res, one = 1;
91 op = x;
92 res = 0;
93
94 one = one << 62;
95 while (one > op)
96 one >>= 2;
97
98 while (one != 0) {
99 if (op >= res + one) {
100 op = op - (res + one);
101 res = res + 2 * one;
102 }
103 res /= 2;
104 one /= 4;
105 }
106 // PARA_NOTICE_LOG("sqrt(%llu) = %llu\n", x, res);
107 return res;
108 }
109
110 /* returns 1 if row matches score item, 0 if not. */
111 static int get_item_score(struct mood_item *item, const struct afs_info *afsi,
112 const struct afh_info *afhi, const char *path, long *score,
113 long *score_arg_sum)
114 {
115 int ret, match = 1;
116
117 *score_arg_sum += item->random_score? 100 : PARA_ABS(item->score_arg);
118 ret = 100;
119 if (item->method) {
120 ret = item->method->score_function(path, afsi, afhi,
121 item->parser_data);
122 if ((ret < 0 && !item->logical_not) || (ret >= 0 && item->logical_not))
123 match = 0; /* no match */
124 }
125 if (item->random_score)
126 *score = PARA_ABS(ret) * para_random(100);
127 else
128 *score = PARA_ABS(ret) * item->score_arg;
129 return match;
130 }
131
132 /* returns 1 if row admissible, 0 if not, negative on errors */
133 static int compute_mood_score(const struct osl_row *aft_row, struct mood *m,
134 long *result)
135 {
136 struct mood_item *item;
137 int ret, match = 0;
138 long score_arg_sum = 0, score = 0, item_score;
139 struct afs_info afsi;
140 struct afh_info afhi;
141 char *path;
142
143 if (!m)
144 return -E_NO_MOOD;
145 ret = get_afsi_of_row(aft_row, &afsi);
146 if (ret< 0)
147 return ret;
148 ret = get_afhi_of_row(aft_row, &afhi);
149 if (ret< 0)
150 return ret;
151 ret = get_audio_file_path_of_row(aft_row, &path);
152 if (ret< 0)
153 return ret;
154 /* reject audio file if it matches any entry in the deny list */
155 list_for_each_entry(item, &m->deny_list, mood_item_node) {
156 ret = get_item_score(item, &afsi, &afhi, path, &item_score,
157 &score_arg_sum);
158 if (ret > 0) /* not admissible */
159 return 0;
160 score += item_score;
161 }
162 list_for_each_entry(item, &m->accept_list, mood_item_node) {
163 ret = get_item_score(item, &afsi, &afhi, path, &item_score,
164 &score_arg_sum);
165 if (ret == 0)
166 continue;
167 match = 1;
168 score += item_score;
169 }
170 /* reject if there is no matching entry in the accept list */
171 if (!match && !list_empty(&m->accept_list))
172 return 0;
173 list_for_each_entry(item, &m->score_list, mood_item_node) {
174 ret = get_item_score(item, &afsi, &afhi, path, &item_score,
175 &score_arg_sum);
176 score += item_score;
177 }
178 if (score_arg_sum)
179 score /= score_arg_sum;
180 *result = score;
181 return 1;
182 }
183
184 static void cleanup_list_entry(struct mood_item *item)
185 {
186 if (item->method && item->method->cleanup)
187 item->method->cleanup(item->parser_data);
188 else
189 free(item->parser_data);
190 list_del(&item->mood_item_node);
191 free(item);
192 }
193
194 static void destroy_mood(struct mood *m)
195 {
196 struct mood_item *tmp, *item;
197
198 if (!m)
199 return;
200 list_for_each_entry_safe(item, tmp, &m->accept_list, mood_item_node)
201 cleanup_list_entry(item);
202 list_for_each_entry_safe(item, tmp, &m->deny_list, mood_item_node)
203 cleanup_list_entry(item);
204 list_for_each_entry_safe(item, tmp, &m->score_list, mood_item_node)
205 cleanup_list_entry(item);
206 free(m->name);
207 free(m);
208 }
209
210 static struct mood *alloc_new_mood(const char *name)
211 {
212 struct mood *m = para_calloc(sizeof(struct mood));
213 m->name = para_strdup(name);
214 INIT_LIST_HEAD(&m->accept_list);
215 INIT_LIST_HEAD(&m->deny_list);
216 INIT_LIST_HEAD(&m->score_list);
217 return m;
218 }
219
220 /** The different types of a mood line. */
221 enum mood_line_type {
222 /** Invalid. */
223 ML_INVALID,
224 /** Accept line. */
225 ML_ACCEPT,
226 /** Deny line. */
227 ML_DENY,
228 /** Score line. */
229 ML_SCORE
230 };
231
232 /** Data passed to the parser of a mood line. */
233 struct mood_line_parser_data {
234 /** The mood this mood line belongs to. */
235 struct mood *m;
236 /** The line number in the mood definition. */
237 unsigned line_num;
238 };
239
240 /*
241 * <accept [with score <score>] | deny [with score <score>] | score <score>>
242 * [if] [not] <mood_method> [options]
243 * <score> is either an integer or "random" which assigns a random score to
244 * all matching files
245 */
246
247 static int parse_mood_line(char *mood_line, void *data)
248 {
249 struct mood_line_parser_data *mlpd = data;
250 char **argv;
251 unsigned num_words;
252 char **w;
253 int i, ret;
254 enum mood_line_type mlt = ML_INVALID;
255 struct mood_item *mi = NULL;
256
257 mlpd->line_num++;
258 ret = create_argv(mood_line, " \t", &argv);
259 if (ret < 0)
260 return ret;
261 num_words = ret;
262 if (!num_words) /* empty line */
263 goto out;
264 w = argv;
265 if (**w == '#') /* comment */
266 goto out;
267 if (!strcmp(*w, "accept"))
268 mlt = ML_ACCEPT;
269 else if (!strcmp(*w, "deny"))
270 mlt = ML_DENY;
271 else if (!strcmp(*w, "score"))
272 mlt = ML_SCORE;
273 ret = -E_MOOD_SYNTAX;
274 if (mlt == ML_INVALID)
275 goto out;
276 mi = para_calloc(sizeof(struct mood_item));
277 if (mlt != ML_SCORE) {
278 ret = -E_MOOD_SYNTAX;
279 w++;
280 if (!*w)
281 goto out;
282 if (strcmp(*w, "with"))
283 goto check_for_if;
284 w++;
285 if (!*w)
286 goto out;
287 if (strcmp(*w, "score"))
288 goto out;
289 }
290 if (mlt == ML_SCORE || !strcmp(*w, "score")) {
291 ret = -E_MOOD_SYNTAX;
292 w++;
293 if (!*w)
294 goto out;
295 if (strcmp(*w, "random")) {
296 mi->random_score = 0;
297 ret = para_atoi32(*w, &mi->score_arg);
298 if (ret < 0)
299 goto out;
300 } else {
301 mi->random_score = 1;
302 if (!*(w + 1))
303 goto success; /* the line "score random" is valid */
304 }
305 } else
306 mi->score_arg = 0;
307 ret = -E_MOOD_SYNTAX;
308 w++;
309 if (!*w)
310 goto out;
311 check_for_if:
312 if (!strcmp(*w, "if")) {
313 ret = -E_MOOD_SYNTAX;
314 w++;
315 if (!*w)
316 goto out;
317 }
318 if (!strcmp(*w, "not")) {
319 ret = -E_MOOD_SYNTAX;
320 w++;
321 if (!*w)
322 goto out;
323 mi->logical_not = 1;
324 } else
325 mi->logical_not = 0;
326 for (i = 0; mood_methods[i].parser; i++) {
327 if (strcmp(*w, mood_methods[i].name))
328 continue;
329 break;
330 }
331 ret = -E_MOOD_SYNTAX;
332 if (!mood_methods[i].parser)
333 goto out;
334 ret = mood_methods[i].parser(num_words - 1 - (w - argv), w,
335 &mi->parser_data);
336 if (ret < 0)
337 goto out;
338 mi->method = &mood_methods[i];
339 success:
340 if (mlpd->m) {
341 if (mlt == ML_ACCEPT)
342 para_list_add(&mi->mood_item_node, &mlpd->m->accept_list);
343 else if (mlt == ML_DENY)
344 para_list_add(&mi->mood_item_node, &mlpd->m->deny_list);
345 else
346 para_list_add(&mi->mood_item_node, &mlpd->m->score_list);
347 }
348 PARA_DEBUG_LOG("%s entry added, method: %p\n", mlt == ML_ACCEPT? "accept" :
349 (mlt == ML_DENY? "deny" : "score"), mi->method);
350 ret = 1;
351 out:
352 free_argv(argv);
353 if (ret >= 0)
354 return ret;
355 if (mi) {
356 free(mi->parser_data);
357 free(mi);
358 }
359 return ret;
360 }
361
362 static int load_mood(const struct osl_row *mood_row, struct mood **m)
363 {
364 char *mood_name;
365 struct osl_object mood_def;
366 struct mood_line_parser_data mlpd = {.line_num = 0};
367 int ret;
368
369 *m = NULL;
370 ret = mood_get_name_and_def_by_row(mood_row, &mood_name, &mood_def);
371 if (ret < 0)
372 return ret;
373 if (!*mood_name)
374 return -E_DUMMY_ROW;
375 mlpd.m = alloc_new_mood(mood_name);
376 ret = for_each_line_ro(mood_def.data, mood_def.size,
377 parse_mood_line, &mlpd);
378 osl_close_disk_object(&mood_def);
379 if (ret < 0) {
380 PARA_ERROR_LOG("unable to load mood %s: %s\n", mlpd.m->name,
381 para_strerror(-ret));
382 destroy_mood(mlpd.m);
383 return ret;
384 }
385 *m = mlpd.m;
386 return 1;
387 }
388
389 static int check_mood(struct osl_row *mood_row, void *data)
390 {
391 struct para_buffer *pb = data;
392 char *mood_name;
393 struct osl_object mood_def;
394 struct mood_line_parser_data mlpd = {.line_num = 0};
395
396 int ret = mood_get_name_and_def_by_row(mood_row, &mood_name, &mood_def);
397
398 if (ret < 0) {
399 para_printf(pb, "failed to get mood definition: %s\n",
400 para_strerror(-ret));
401 return ret;
402 }
403 if (!*mood_name) /* ignore dummy row */
404 goto out;
405 ret = para_printf(pb, "checking mood %s...\n", mood_name);
406 if (ret < 0)
407 goto out;
408 ret = for_each_line_ro(mood_def.data, mood_def.size,
409 parse_mood_line, &mlpd);
410 if (ret < 0)
411 para_printf(pb, "%s line %u: %s\n", mood_name, mlpd.line_num,
412 para_strerror(-ret));
413 out:
414 osl_close_disk_object(&mood_def);
415 return ret;
416 }
417
418 /**
419 * Check all moods for syntax errors.
420 *
421 * \param fd The afs socket.
422 * \param query Unused.
423 */
424 void mood_check_callback(int fd, __a_unused const struct osl_object *query)
425 {
426 struct para_buffer pb = {
427 .max_size = shm_get_shmmax(),
428 .private_data = &fd,
429 .max_size_handler = pass_buffer_as_shm
430 };
431
432 int ret = para_printf(&pb, "checking moods...\n");
433 if (ret < 0)
434 return;
435 osl_rbtree_loop(moods_table, BLOBCOL_ID, &pb,
436 check_mood);
437 if (pb.offset)
438 pass_buffer_as_shm(pb.buf, pb.offset, &fd);
439 free(pb.buf);
440 }
441
442 #if 0
443 static unsigned int_log2(uint64_t x)
444 {
445 unsigned res = 0;
446
447 while (x) {
448 x /= 2;
449 res++;
450 }
451 return res;
452 }
453 #endif
454
455 static int64_t normalized_value(int64_t x, int64_t n, int64_t sum, int64_t qd)
456 {
457 if (!n || !qd)
458 return 0;
459 return 100 * (n * x - sum) / (int64_t)int_sqrt(n * qd);
460 }
461
462 static long compute_num_played_score(struct afs_info *afsi)
463 {
464 return -normalized_value(afsi->num_played, statistics.num,
465 statistics.num_played_sum, statistics.num_played_qd);
466 }
467
468 static long compute_last_played_score(struct afs_info *afsi)
469 {
470 return -normalized_value(afsi->last_played, statistics.num,
471 statistics.last_played_sum, statistics.last_played_qd);
472 }
473
474 static long compute_dynamic_score(const struct osl_row *aft_row)
475 {
476 struct afs_info afsi;
477 int64_t score, nscore = 0, lscore = 0;
478 int ret;
479
480 ret = get_afsi_of_row(aft_row, &afsi);
481 if (ret < 0)
482 return -100;
483 nscore = compute_num_played_score(&afsi);
484 lscore = compute_last_played_score(&afsi);
485 score = nscore + lscore;
486 return score;
487 }
488
489 static int add_afs_statistics(const struct osl_row *row)
490 {
491 uint64_t n, x, s;
492 struct afs_info afsi;
493 int ret;
494
495 ret = get_afsi_of_row(row, &afsi);
496 if (ret < 0)
497 return ret;
498 n = statistics.num;
499 x = afsi.last_played;
500 s = statistics.last_played_sum;
501 if (n > 0)
502 statistics.last_played_qd += (x - s / n) * (x - s / n) * n / (n + 1);
503 statistics.last_played_sum += x;
504
505 x = afsi.num_played;
506 s = statistics.num_played_sum;
507 if (n > 0)
508 statistics.num_played_qd += (x - s / n) * (x - s / n) * n / (n + 1);
509 statistics.num_played_sum += x;
510 statistics.num++;
511 return 1;
512 }
513
514 static int del_afs_statistics(const struct osl_row *row)
515 {
516 uint64_t n, s, q, a, new_s;
517 struct afs_info afsi;
518 int ret;
519 ret = get_afsi_of_row(row, &afsi);
520 if (ret < 0)
521 return ret;
522 n = statistics.num;
523 assert(n);
524 if (n == 1) {
525 memset(&statistics, 0, sizeof(statistics));
526 return 1;
527 }
528
529 s = statistics.last_played_sum;
530 q = statistics.last_played_qd;
531 a = afsi.last_played;
532 new_s = s - a;
533 statistics.last_played_sum = new_s;
534 statistics.last_played_qd = q + s * s / n - a * a
535 - new_s * new_s / (n - 1);
536
537 s = statistics.num_played_sum;
538 q = statistics.num_played_qd;
539 a = afsi.num_played;
540 new_s = s - a;
541 statistics.num_played_sum = new_s;
542 statistics.num_played_qd = q + s * s / n - a * a
543 - new_s * new_s / (n - 1);
544
545 statistics.num--;
546 return 1;
547 }
548
549 /**
550 * Structure used during mood_open().
551 *
552 * At mood open time, we look at each file in the audio file table in order to
553 * determine whether it is admissible. If a file happens to be admissible, its
554 * mood score is computed by calling each relevant mood_score_function. Next,
555 * we update the afs_statistics and add a struct admissible_file_info to a
556 * temporary array.
557 *
558 * If all files have been processed that way, the final score of each
559 * admissible file is computed by adding the dynamic score (which depends on
560 * the afs_statistics) to the mood score. Finally, all audio files in the
561 * array are added to the score table and the admissible array is freed.
562 *
563 * \sa mood_method, admissible_array.
564 */
565 struct admissible_file_info
566 {
567 /** The admissible audio file. */
568 struct osl_row *aft_row;
569 /** Its score. */
570 long score;
571 };
572
573 /** The temporary array of admissible files. */
574 struct admissible_array {
575 /** Files are admissible wrt. this mood. */
576 struct mood *m;
577 /** The size of the array */
578 unsigned size;
579 /** Pointer to the array of admissible files. */
580 struct admissible_file_info *array;
581 };
582
583 /**
584 * Add an entry to the array of admissible files.
585 *
586 * \param aft_row The audio file to be added.
587 * \param private_data Pointer to a struct admissible_file_info.
588 *
589 * \return 1 if row admissible, 0 if not, negative on errors.
590 */
591 static int add_if_admissible(struct osl_row *aft_row, void *data)
592 {
593 struct admissible_array *aa = data;
594 int ret;
595 long score = 0;
596
597 ret = compute_mood_score(aft_row, aa->m, &score);
598 if (ret <= 0)
599 return ret;
600 if (statistics.num >= aa->size) {
601 aa->size *= 2;
602 aa->size += 100;
603 aa->array = para_realloc(aa->array,
604 aa->size * sizeof(struct admissible_file_info));
605 }
606 aa->array[statistics.num].aft_row = aft_row;
607 aa->array[statistics.num].score = score;
608 ret = add_afs_statistics(aft_row);
609 if (ret < 0)
610 return ret;
611 return 1;
612 }
613
614 /**
615 * Compute the new quadratic deviation in case one element changes.
616 *
617 * \param n Number of elements.
618 * \param old_qd The quadratic deviation before the change.
619 * \param old_val The value that was replaced.
620 * \param new_val The replacement value.
621 * \param old_sum The sum of all elements before the update.
622 *
623 * \return The new quadratic deviation resulting from replacing old_val
624 * by new_val.
625 *
626 * Given n real numbers a_1, ..., a_n, their sum S = a_1 + ... + a_n,
627 * their quadratic deviation
628 *
629 * q = (a_1 - S/n)^2 + ... + (a_n - S/n)^2,
630 *
631 * and a real number b, the quadratic deviation q' of a_1,...a_{n-1}, b (ie.
632 * the last number a_n was replaced by b) may be computed in O(1) time in terms
633 * of n, q, a_n, b, and S as
634 *
635 * q' = q + d * s - (2 * S + d) * d / n,
636 *
637 * where d = b - a_n, and s = b + a_n.
638 *
639 * Example: n = 3, a_1 = 3, a_2 = 5, a_3 = 7, b = 10. Then S = 15, q = 8, d = 3,
640 * s = 17, so
641 *
642 * q + d * s - (2 * S + d) * d / n = 8 + 51 - 33 = 26,
643 *
644 * which equals q' = (3 - 6)^2 + (5 - 6)^2 + (10 - 6)^2.
645 *
646 */
647 _static_inline_ int64_t update_quadratic_deviation(int64_t n, int64_t old_qd,
648 int64_t old_val, int64_t new_val, int64_t old_sum)
649 {
650 int64_t delta = new_val - old_val;
651 int64_t sigma = new_val + old_val;
652 return old_qd + delta * sigma - (2 * old_sum + delta) * delta / n;
653 }
654
655 static int update_afs_statistics(struct afs_info *old_afsi, struct afs_info *new_afsi)
656 {
657 unsigned n;
658 int ret = get_num_admissible_files(&n);
659
660 if (ret < 0)
661 return ret;
662 assert(n);
663
664 statistics.last_played_qd = update_quadratic_deviation(n,
665 statistics.last_played_qd, old_afsi->last_played,
666 new_afsi->last_played, statistics.last_played_sum);
667 statistics.last_played_sum += new_afsi->last_played - old_afsi->last_played;
668
669 statistics.num_played_qd = update_quadratic_deviation(n,
670 statistics.num_played_qd, old_afsi->num_played,
671 new_afsi->num_played, statistics.num_played_sum);
672 statistics.num_played_sum += new_afsi->num_played - old_afsi->num_played;
673 return 1;
674 }
675
676 static int add_to_score_table(const struct osl_row *aft_row, long mood_score)
677 {
678 long score = (compute_dynamic_score(aft_row) + mood_score) / 3;
679 return score_add(aft_row, score);
680 }
681
682 static int delete_from_statistics_and_score_table(const struct osl_row *aft_row)
683 {
684 int ret = del_afs_statistics(aft_row);
685 if (ret < 0)
686 return ret;
687 return score_delete(aft_row);
688 }
689
690 /**
691 * Delete one entry from the statistics and from the score table.
692 *
693 * \param aft_row The audio file which is no longer admissible.
694 *
695 * \return Positive on success, negative on errors.
696 *
697 * \sa score_delete().
698 */
699 static int mood_delete_audio_file(const struct osl_row *aft_row)
700 {
701 int ret;
702
703 ret = row_belongs_to_score_table(aft_row, NULL);
704 if (ret < 0)
705 return ret;
706 if (!ret) /* not admissible, nothing to do */
707 return 1;
708 return delete_from_statistics_and_score_table(aft_row);
709 }
710
711 /**
712 * Compute the new score of an audio file wrt. the current mood.
713 *
714 * \param aft_row Determines the audio file.
715 * \param old_afsi The audio file selector info before updating.
716 *
717 * The \a old_afsi argument may be \p NULL which indicates that no changes to
718 * the audio file info were made.
719 *
720 * \return Positive on success, negative on errors.
721 */
722 static int mood_update_audio_file(const struct osl_row *aft_row,
723 struct afs_info *old_afsi)
724 {
725 long score, percent;
726 int ret, is_admissible, was_admissible = 0;
727 struct afs_info afsi;
728 unsigned rank;
729
730 if (!current_mood)
731 return 1; /* nothing to do */
732 ret = row_belongs_to_score_table(aft_row, &rank);
733 if (ret < 0)
734 return ret;
735 was_admissible = ret;
736 ret = compute_mood_score(aft_row, current_mood, &score);
737 if (ret < 0)
738 return ret;
739 is_admissible = (ret > 0);
740 if (!was_admissible && !is_admissible)
741 return 1;
742 if (was_admissible && !is_admissible)
743 return delete_from_statistics_and_score_table(aft_row);
744 if (!was_admissible && is_admissible) {
745 ret = add_afs_statistics(aft_row);
746 if (ret < 0)
747 return ret;
748 return add_to_score_table(aft_row, score);
749 }
750 /* update score */
751 ret = get_afsi_of_row(aft_row, &afsi);
752 if (ret < 0)
753 return ret;
754 if (old_afsi) {
755 ret = update_afs_statistics(old_afsi, &afsi);
756 if (ret < 0)
757 return ret;
758 }
759 score += compute_num_played_score(&afsi);
760 score += compute_last_played_score(&afsi);
761 score /= 3;
762 PARA_DEBUG_LOG("score: %li\n", score);
763 percent = (score + 100) / 3;
764 if (percent > 100)
765 percent = 100;
766 else if (percent < 0)
767 percent = 0;
768 PARA_DEBUG_LOG("moving from rank %u to %lu%%\n", rank, percent);
769 return score_update(aft_row, percent);
770 }
771
772 static void log_statistics(void)
773 {
774 unsigned n = statistics.num;
775
776 if (!n) {
777 PARA_NOTICE_LOG("no admissible files\n");
778 return;
779 }
780 PARA_INFO_LOG("last_played mean: %lli, last_played sigma: %llu\n",
781 (long long int)(statistics.last_played_sum / n),
782 (long long unsigned)int_sqrt(statistics.last_played_qd / n));
783 PARA_INFO_LOG("num_played mean: %lli, num_played sigma: %llu\n",
784 (long long int)statistics.num_played_sum / n,
785 (long long unsigned)int_sqrt(statistics.num_played_qd / n));
786 }
787
788 /**
789 * Close the current mood.
790 *
791 * Free all resources of the current mood which were allocated during
792 * mood_open().
793 */
794 void close_current_mood(void)
795 {
796 destroy_mood(current_mood);
797 current_mood = NULL;
798 memset(&statistics, 0, sizeof(statistics));
799 }
800
801 /**
802 * Change the current mood.
803 *
804 * \param mood_name The name of the mood to open.
805 *
806 * If \a mood_name is \a NULL, load the dummy mood that accepts every audio file
807 * and uses a scoring method based only on the \a last_played information.
808 *
809 * If there is already an open mood, it will be closed first.
810 *
811 * \return Positive on success, negative on errors. Loading the dummy mood
812 * always succeeds.
813 *
814 * \sa struct admissible_file_info, struct admissible_array, struct
815 * afs_info::last_played, mood_close().
816 */
817 int change_current_mood(char *mood_name)
818 {
819 int i, ret;
820 struct admissible_array aa = {
821 .size = 0,
822 .array = NULL
823 };
824
825 if (mood_name) {
826 struct mood *m;
827 struct osl_row *row;
828 struct osl_object obj = {
829 .data = mood_name,
830 .size = strlen(mood_name) + 1
831 };
832 ret = osl(osl_get_row(moods_table, BLOBCOL_NAME, &obj, &row));
833 if (ret < 0) {
834 PARA_NOTICE_LOG("no such mood: %s\n", mood_name);
835 return ret;
836 }
837 ret = load_mood(row, &m);
838 if (ret < 0)
839 return ret;
840 close_current_mood();
841 current_mood = m;
842 } else {
843 close_current_mood();
844 current_mood = alloc_new_mood("dummy");
845 }
846 aa.m = current_mood;
847 PARA_NOTICE_LOG("computing statistics of admissible files\n");
848 ret = audio_file_loop(&aa, add_if_admissible);
849 if (ret < 0)
850 return ret;
851 log_statistics();
852 PARA_INFO_LOG("%d admissible files \n", statistics.num);
853 for (i = 0; i < statistics.num; i++) {
854 struct admissible_file_info *a = aa.array + i;
855 ret = add_to_score_table(a->aft_row, a->score);
856 if (ret < 0)
857 goto out;
858 }
859 PARA_NOTICE_LOG("loaded mood %s\n", current_mood->name);
860 ret = statistics.num;
861 out:
862 free(aa.array);
863 return ret;
864 }
865 /**
866 * Close and re-open the current mood.
867 *
868 * This function is used if changes to the audio file table or the
869 * attribute table were made that render the current list of admissible
870 * files useless. For example, if an attribute is removed from the
871 * attribute table, this function is called.
872 *
873 * \return Positive on success, negative on errors. If no mood is currently
874 * open, the function returns success.
875 *
876 * \sa mood_open(), mood_close().
877 */
878 static int reload_current_mood(void)
879 {
880 int ret;
881 char *mood_name = NULL;
882
883 if (!current_mood)
884 return 1;
885 PARA_NOTICE_LOG("reloading %s\n", current_mood->name?
886 current_mood->name : "(dummy)");
887 if (current_mood->name)
888 mood_name = para_strdup(current_mood->name);
889 close_current_mood();
890 ret = change_current_mood(mood_name);
891 free(mood_name);
892 return ret;
893 }
894
895 /**
896 * Notification callback for the moods table.
897 *
898 * \param event Type of the event just occurred.
899 * \param pb Unused.
900 * \param data Its type depends on the event.
901 *
902 * This function performs actions required due to the occurrence of the given
903 * event. Possible actions include reload of the current mood and update of the
904 * score of an audio file.
905 */
906 int moods_event_handler(enum afs_events event, __a_unused struct para_buffer *pb,
907 void *data)
908 {
909 int ret;
910
911 if (!current_mood)
912 return 0;
913 switch (event) {
914 /*
915 * The three blob events might change the set of admissible files,
916 * so we must reload the score list.
917 */
918 case BLOB_RENAME:
919 case BLOB_REMOVE:
920 case BLOB_ADD:
921 if (data == moods_table || data == playlists_table)
922 return 1; /* no reload necessary for these */
923 ret = clear_score_table();
924 if (ret < 0)
925 PARA_CRIT_LOG("clear score table returned %s\n",
926 para_strerror(-ret));
927 return reload_current_mood();
928 /* these also require reload of the score table */
929 case ATTRIBUTE_ADD:
930 case ATTRIBUTE_REMOVE:
931 case ATTRIBUTE_RENAME:
932 return reload_current_mood();
933 /* changes to the aft only require to re-examine the audio file */
934 case AFSI_CHANGE: {
935 struct afsi_change_event_data *aced = data;
936 return mood_update_audio_file(aced->aft_row, aced->old_afsi);
937 }
938 case AFHI_CHANGE:
939 case AUDIO_FILE_RENAME:
940 case AUDIO_FILE_ADD:
941 return mood_update_audio_file(data, NULL);
942 case AUDIO_FILE_REMOVE:
943 return mood_delete_audio_file(data);
944 default:
945 return 1;
946 }
947 }