d15e011f04c720cef376b73752d9fcba51c61f00
[paraslash.git] / mood.c
1 /*
2 * Copyright (C) 2007-2013 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 #include "sideband.h"
21
22 /**
23 * Contains statistical data of the currently admissible audio files.
24 *
25 * It is used to assign normalized score values to each admissible audio file.
26 */
27 struct afs_statistics {
28 /** Sum of num played over all admissible files. */
29 int64_t num_played_sum;
30 /** Sum of last played times over all admissible files. */
31 int64_t last_played_sum;
32 /** Quadratic deviation of num played time. */
33 int64_t num_played_qd;
34 /** Quadratic deviation of last played time. */
35 int64_t last_played_qd;
36 /** Number of admissible files */
37 unsigned num;
38 };
39 static struct afs_statistics statistics;
40
41 /**
42 * Each line of the current mood corresponds to a mood_item.
43 */
44 struct mood_item {
45 /** The method this line is referring to. */
46 const struct mood_method *method;
47 /** The data structure computed by the mood parser. */
48 void *parser_data;
49 /** The given score value, or zero if none was given. */
50 int32_t score_arg;
51 /** Non-zero if random scoring was requested. */
52 int random_score;
53 /** Whether the "not" keyword was given in the mood line. */
54 int logical_not;
55 /** The position in the list of items. */
56 struct list_head mood_item_node;
57 };
58
59 /**
60 * Created from the mood definition by mood_open().
61 *
62 * When a mood is opened, each line of its definition is investigated, and a
63 * corresponding mood item is produced. Each mood line starts with \p accept,
64 * \p deny, or \p score which determines the type of the mood line. For each
65 * such type a linked list is maintained whose entries are the mood items.
66 *
67 * \sa mood_item, mood_open().
68 */
69 struct mood {
70 /** The name of this mood. */
71 char *name;
72 /** The list of mood items of type \p accept. */
73 struct list_head accept_list;
74 /** The list of mood items of type \p deny. */
75 struct list_head deny_list;
76 /** The list of mood items of type \p score. */
77 struct list_head score_list;
78 };
79
80 /*
81 * If current_mood is NULL then no mood is currently open. If
82 * current_mood->name is NULL, the dummy mood is currently open
83 */
84 static struct mood *current_mood;
85
86 /**
87 * Rough approximation to sqrt.
88 *
89 * \param x Integer of which to calculate the sqrt.
90 *
91 * \return An integer res with res * res <= x.
92 */
93 __a_const static uint64_t int_sqrt(uint64_t x)
94 {
95 uint64_t op, res, one = 1;
96 op = x;
97 res = 0;
98
99 one = one << 62;
100 while (one > op)
101 one >>= 2;
102
103 while (one != 0) {
104 if (op >= res + one) {
105 op = op - (res + one);
106 res = res + 2 * one;
107 }
108 res /= 2;
109 one /= 4;
110 }
111 // PARA_NOTICE_LOG("sqrt(%llu) = %llu\n", x, res);
112 return res;
113 }
114
115 /*
116 * Returns true if row matches, false if it does not match. In any case score
117 * and score_arg_sum are set/increased accordingly.
118 */
119 static bool get_item_score(struct mood_item *item, const struct afs_info *afsi,
120 const struct afh_info *afhi, const char *path, long *score,
121 long *score_arg_sum)
122 {
123 int ret;
124 bool match = true;
125
126 *score_arg_sum += item->random_score? 100 : PARA_ABS(item->score_arg);
127 ret = 100;
128 if (item->method) {
129 ret = item->method->score_function(path, afsi, afhi,
130 item->parser_data);
131 if ((ret < 0 && !item->logical_not) || (ret >= 0 && item->logical_not))
132 match = false;
133 }
134 if (item->random_score)
135 *score = PARA_ABS(ret) * para_random(100);
136 else
137 *score = PARA_ABS(ret) * item->score_arg;
138 return match;
139 }
140
141 /* returns 1 if row admissible, 0 if not, negative on errors */
142 static int compute_mood_score(const struct osl_row *aft_row, struct mood *m,
143 long *result)
144 {
145 struct mood_item *item;
146 int ret;
147 bool match;
148 long score_arg_sum = 0, score = 0, item_score;
149 struct afs_info afsi;
150 struct afh_info afhi;
151 char *path;
152
153 if (!m)
154 return -E_NO_MOOD;
155 ret = get_afsi_of_row(aft_row, &afsi);
156 if (ret< 0)
157 return ret;
158 ret = get_afhi_of_row(aft_row, &afhi);
159 if (ret< 0)
160 return ret;
161 ret = get_audio_file_path_of_row(aft_row, &path);
162 if (ret< 0)
163 return ret;
164 /* reject audio file if it matches any entry in the deny list */
165 list_for_each_entry(item, &m->deny_list, mood_item_node) {
166 match = get_item_score(item, &afsi, &afhi, path, &item_score,
167 &score_arg_sum);
168 if (match) /* not admissible */
169 return 0;
170 score += item_score;
171 }
172 match = false;
173 list_for_each_entry(item, &m->accept_list, mood_item_node) {
174 ret = get_item_score(item, &afsi, &afhi, path, &item_score,
175 &score_arg_sum);
176 if (ret == 0)
177 continue;
178 match = true;
179 score += item_score;
180 }
181 /* reject if there is no matching entry in the accept list */
182 if (!match && !list_empty(&m->accept_list))
183 return 0;
184 list_for_each_entry(item, &m->score_list, mood_item_node) {
185 match = get_item_score(item, &afsi, &afhi, path, &item_score,
186 &score_arg_sum);
187 if (match)
188 score += item_score;
189 }
190 if (score_arg_sum)
191 score /= score_arg_sum;
192 *result = score;
193 return 1;
194 }
195
196 static void cleanup_list_entry(struct mood_item *item)
197 {
198 if (item->method && item->method->cleanup)
199 item->method->cleanup(item->parser_data);
200 else
201 free(item->parser_data);
202 list_del(&item->mood_item_node);
203 free(item);
204 }
205
206 static void destroy_mood(struct mood *m)
207 {
208 struct mood_item *tmp, *item;
209
210 if (!m)
211 return;
212 list_for_each_entry_safe(item, tmp, &m->accept_list, mood_item_node)
213 cleanup_list_entry(item);
214 list_for_each_entry_safe(item, tmp, &m->deny_list, mood_item_node)
215 cleanup_list_entry(item);
216 list_for_each_entry_safe(item, tmp, &m->score_list, mood_item_node)
217 cleanup_list_entry(item);
218 free(m->name);
219 free(m);
220 }
221
222 static struct mood *alloc_new_mood(const char *name)
223 {
224 struct mood *m = para_calloc(sizeof(struct mood));
225 if (name)
226 m->name = para_strdup(name);
227 INIT_LIST_HEAD(&m->accept_list);
228 INIT_LIST_HEAD(&m->deny_list);
229 INIT_LIST_HEAD(&m->score_list);
230 return m;
231 }
232
233 /** The different types of a mood line. */
234 enum mood_line_type {
235 /** Invalid. */
236 ML_INVALID,
237 /** Accept line. */
238 ML_ACCEPT,
239 /** Deny line. */
240 ML_DENY,
241 /** Score line. */
242 ML_SCORE
243 };
244
245 /** Data passed to the parser of a mood line. */
246 struct mood_line_parser_data {
247 /** The mood this mood line belongs to. */
248 struct mood *m;
249 /** The line number in the mood definition. */
250 unsigned line_num;
251 };
252
253 /*
254 * <accept [with score <score>] | deny [with score <score>] | score <score>>
255 * [if] [not] <mood_method> [options]
256 * <score> is either an integer or "random" which assigns a random score to
257 * all matching files
258 */
259
260 static int parse_mood_line(char *mood_line, void *data)
261 {
262 struct mood_line_parser_data *mlpd = data;
263 char **argv;
264 unsigned num_words;
265 char **w;
266 int i, ret;
267 enum mood_line_type mlt = ML_INVALID;
268 struct mood_item *mi = NULL;
269
270 mlpd->line_num++;
271 ret = create_argv(mood_line, " \t", &argv);
272 if (ret < 0)
273 return ret;
274 num_words = ret;
275 if (!num_words) /* empty line */
276 goto out;
277 w = argv;
278 if (**w == '#') /* comment */
279 goto out;
280 if (!strcmp(*w, "accept"))
281 mlt = ML_ACCEPT;
282 else if (!strcmp(*w, "deny"))
283 mlt = ML_DENY;
284 else if (!strcmp(*w, "score"))
285 mlt = ML_SCORE;
286 ret = -E_MOOD_SYNTAX;
287 if (mlt == ML_INVALID)
288 goto out;
289 mi = para_calloc(sizeof(struct mood_item));
290 if (mlt != ML_SCORE) {
291 ret = -E_MOOD_SYNTAX;
292 w++;
293 if (!*w)
294 goto out;
295 if (strcmp(*w, "with"))
296 goto check_for_if;
297 w++;
298 if (!*w)
299 goto out;
300 if (strcmp(*w, "score"))
301 goto out;
302 }
303 if (mlt == ML_SCORE || !strcmp(*w, "score")) {
304 ret = -E_MOOD_SYNTAX;
305 w++;
306 if (!*w)
307 goto out;
308 if (strcmp(*w, "random")) {
309 mi->random_score = 0;
310 ret = para_atoi32(*w, &mi->score_arg);
311 if (ret < 0)
312 goto out;
313 } else {
314 mi->random_score = 1;
315 if (!*(w + 1))
316 goto success; /* the line "score random" is valid */
317 }
318 } else
319 mi->score_arg = 0;
320 ret = -E_MOOD_SYNTAX;
321 w++;
322 if (!*w)
323 goto out;
324 check_for_if:
325 if (!strcmp(*w, "if")) {
326 ret = -E_MOOD_SYNTAX;
327 w++;
328 if (!*w)
329 goto out;
330 }
331 if (!strcmp(*w, "not")) {
332 ret = -E_MOOD_SYNTAX;
333 w++;
334 if (!*w)
335 goto out;
336 mi->logical_not = 1;
337 } else
338 mi->logical_not = 0;
339 for (i = 0; mood_methods[i].parser; i++) {
340 if (strcmp(*w, mood_methods[i].name))
341 continue;
342 break;
343 }
344 ret = -E_MOOD_SYNTAX;
345 if (!mood_methods[i].parser)
346 goto out;
347 ret = mood_methods[i].parser(num_words - 1 - (w - argv), w,
348 &mi->parser_data);
349 if (ret < 0)
350 goto out;
351 mi->method = &mood_methods[i];
352 success:
353 if (mlpd->m) {
354 if (mlt == ML_ACCEPT)
355 para_list_add(&mi->mood_item_node, &mlpd->m->accept_list);
356 else if (mlt == ML_DENY)
357 para_list_add(&mi->mood_item_node, &mlpd->m->deny_list);
358 else
359 para_list_add(&mi->mood_item_node, &mlpd->m->score_list);
360 }
361 PARA_DEBUG_LOG("%s entry added, method: %p\n", mlt == ML_ACCEPT? "accept" :
362 (mlt == ML_DENY? "deny" : "score"), mi->method);
363 ret = 1;
364 out:
365 free_argv(argv);
366 if (ret >= 0)
367 return ret;
368 if (mi) {
369 free(mi->parser_data);
370 free(mi);
371 }
372 return ret;
373 }
374
375 static int load_mood(const struct osl_row *mood_row, struct mood **m)
376 {
377 char *mood_name;
378 struct osl_object mood_def;
379 struct mood_line_parser_data mlpd = {.line_num = 0};
380 int ret;
381
382 *m = NULL;
383 ret = mood_get_name_and_def_by_row(mood_row, &mood_name, &mood_def);
384 if (ret < 0)
385 return ret;
386 if (!*mood_name)
387 return -E_DUMMY_ROW;
388 mlpd.m = alloc_new_mood(mood_name);
389 ret = for_each_line(FELF_READ_ONLY, mood_def.data, mood_def.size,
390 parse_mood_line, &mlpd);
391 osl_close_disk_object(&mood_def);
392 if (ret < 0) {
393 PARA_ERROR_LOG("unable to load mood %s: %s\n", mlpd.m->name,
394 para_strerror(-ret));
395 destroy_mood(mlpd.m);
396 return ret;
397 }
398 *m = mlpd.m;
399 return 1;
400 }
401
402 static int check_mood(struct osl_row *mood_row, void *data)
403 {
404 struct para_buffer *pb = data;
405 char *mood_name;
406 struct osl_object mood_def;
407 struct mood_line_parser_data mlpd = {.line_num = 0};
408
409 int ret = mood_get_name_and_def_by_row(mood_row, &mood_name, &mood_def);
410
411 if (ret < 0) {
412 para_printf(pb, "failed to get mood definition: %s\n",
413 para_strerror(-ret));
414 return ret;
415 }
416 if (!*mood_name) /* ignore dummy row */
417 goto out;
418 ret = para_printf(pb, "checking mood %s...\n", mood_name);
419 if (ret < 0)
420 goto out;
421 ret = for_each_line(FELF_READ_ONLY, mood_def.data, mood_def.size,
422 parse_mood_line, &mlpd);
423 if (ret < 0)
424 para_printf(pb, "%s line %u: %s\n", mood_name, mlpd.line_num,
425 para_strerror(-ret));
426 out:
427 osl_close_disk_object(&mood_def);
428 return ret;
429 }
430
431 /**
432 * Check all moods for syntax errors.
433 *
434 * \param fd The afs socket.
435 * \param query Unused.
436 */
437 void mood_check_callback(int fd, __a_unused const struct osl_object *query)
438 {
439 struct para_buffer pb = {
440 .max_size = shm_get_shmmax(),
441 .private_data = &(struct afs_max_size_handler_data) {
442 .fd = fd,
443 .band = SBD_OUTPUT
444 },
445 .max_size_handler = afs_max_size_handler
446 };
447
448 int ret = para_printf(&pb, "checking moods...\n");
449 if (ret < 0)
450 return;
451 osl_rbtree_loop(moods_table, BLOBCOL_ID, &pb,
452 check_mood);
453 if (pb.offset)
454 pass_buffer_as_shm(fd, SBD_OUTPUT, pb.buf, pb.offset);
455 free(pb.buf);
456 }
457
458 static int64_t normalized_value(int64_t x, int64_t n, int64_t sum, int64_t qd)
459 {
460 if (!n || !qd)
461 return 0;
462 return 100 * (n * x - sum) / (int64_t)int_sqrt(n * qd);
463 }
464
465 static long compute_score(struct afs_info *afsi, long mood_score)
466 {
467 mood_score -= normalized_value(afsi->num_played, statistics.num,
468 statistics.num_played_sum, statistics.num_played_qd);
469 mood_score -= normalized_value(afsi->last_played, statistics.num,
470 statistics.last_played_sum, statistics.last_played_qd);
471 return mood_score / 3;
472 }
473
474 static int add_afs_statistics(const struct osl_row *row)
475 {
476 uint64_t n, x, s;
477 struct afs_info afsi;
478 int ret;
479
480 ret = get_afsi_of_row(row, &afsi);
481 if (ret < 0)
482 return ret;
483 n = statistics.num;
484 x = afsi.last_played;
485 s = statistics.last_played_sum;
486 if (n > 0)
487 statistics.last_played_qd += (x - s / n) * (x - s / n) * n / (n + 1);
488 statistics.last_played_sum += x;
489
490 x = afsi.num_played;
491 s = statistics.num_played_sum;
492 if (n > 0)
493 statistics.num_played_qd += (x - s / n) * (x - s / n) * n / (n + 1);
494 statistics.num_played_sum += x;
495 statistics.num++;
496 return 1;
497 }
498
499 static int del_afs_statistics(const struct osl_row *row)
500 {
501 uint64_t n, s, q, a, new_s;
502 struct afs_info afsi;
503 int ret;
504 ret = get_afsi_of_row(row, &afsi);
505 if (ret < 0)
506 return ret;
507 n = statistics.num;
508 assert(n);
509 if (n == 1) {
510 memset(&statistics, 0, sizeof(statistics));
511 return 1;
512 }
513
514 s = statistics.last_played_sum;
515 q = statistics.last_played_qd;
516 a = afsi.last_played;
517 new_s = s - a;
518 statistics.last_played_sum = new_s;
519 statistics.last_played_qd = q + s * s / n - a * a
520 - new_s * new_s / (n - 1);
521
522 s = statistics.num_played_sum;
523 q = statistics.num_played_qd;
524 a = afsi.num_played;
525 new_s = s - a;
526 statistics.num_played_sum = new_s;
527 statistics.num_played_qd = q + s * s / n - a * a
528 - new_s * new_s / (n - 1);
529
530 statistics.num--;
531 return 1;
532 }
533
534 /**
535 * Structure used during mood_open().
536 *
537 * At mood open time, we look at each file in the audio file table in order to
538 * determine whether it is admissible. If a file happens to be admissible, its
539 * mood score is computed by calling each relevant mood_score_function. Next,
540 * we update the afs_statistics and add a struct admissible_file_info to a
541 * temporary array.
542 *
543 * If all files have been processed that way, the final score of each
544 * admissible file is computed by adding the dynamic score (which depends on
545 * the afs_statistics) to the mood score. Finally, all audio files in the
546 * array are added to the score table and the admissible array is freed.
547 *
548 * \sa mood_method, admissible_array.
549 */
550 struct admissible_file_info
551 {
552 /** The admissible audio file. */
553 struct osl_row *aft_row;
554 /** Its score. */
555 long score;
556 };
557
558 /** The temporary array of admissible files. */
559 struct admissible_array {
560 /** Files are admissible wrt. this mood. */
561 struct mood *m;
562 /** The size of the array */
563 unsigned size;
564 /** Pointer to the array of admissible files. */
565 struct admissible_file_info *array;
566 };
567
568 /**
569 * Add an entry to the array of admissible files.
570 *
571 * \param aft_row The audio file to be added.
572 * \param private_data Pointer to a struct admissible_file_info.
573 *
574 * \return 1 if row admissible, 0 if not, negative on errors.
575 */
576 static int add_if_admissible(struct osl_row *aft_row, void *data)
577 {
578 struct admissible_array *aa = data;
579 int ret;
580 long score = 0;
581
582 ret = compute_mood_score(aft_row, aa->m, &score);
583 if (ret <= 0)
584 return ret;
585 if (statistics.num >= aa->size) {
586 aa->size *= 2;
587 aa->size += 100;
588 aa->array = para_realloc(aa->array,
589 aa->size * sizeof(struct admissible_file_info));
590 }
591 aa->array[statistics.num].aft_row = aft_row;
592 aa->array[statistics.num].score = score;
593 ret = add_afs_statistics(aft_row);
594 if (ret < 0)
595 return ret;
596 return 1;
597 }
598
599 /**
600 * Compute the new quadratic deviation in case one element changes.
601 *
602 * \param n Number of elements.
603 * \param old_qd The quadratic deviation before the change.
604 * \param old_val The value that was replaced.
605 * \param new_val The replacement value.
606 * \param old_sum The sum of all elements before the update.
607 *
608 * \return The new quadratic deviation resulting from replacing old_val
609 * by new_val.
610 *
611 * Given n real numbers a_1, ..., a_n, their sum S = a_1 + ... + a_n,
612 * their quadratic deviation
613 *
614 * q = (a_1 - S/n)^2 + ... + (a_n - S/n)^2,
615 *
616 * and a real number b, the quadratic deviation q' of a_1,...a_{n-1}, b (ie.
617 * the last number a_n was replaced by b) may be computed in O(1) time in terms
618 * of n, q, a_n, b, and S as
619 *
620 * q' = q + d * s - (2 * S + d) * d / n,
621 *
622 * where d = b - a_n, and s = b + a_n.
623 *
624 * Example: n = 3, a_1 = 3, a_2 = 5, a_3 = 7, b = 10. Then S = 15, q = 8, d = 3,
625 * s = 17, so
626 *
627 * q + d * s - (2 * S + d) * d / n = 8 + 51 - 33 = 26,
628 *
629 * which equals q' = (3 - 6)^2 + (5 - 6)^2 + (10 - 6)^2.
630 *
631 */
632 _static_inline_ int64_t update_quadratic_deviation(int64_t n, int64_t old_qd,
633 int64_t old_val, int64_t new_val, int64_t old_sum)
634 {
635 int64_t delta = new_val - old_val;
636 int64_t sigma = new_val + old_val;
637 return old_qd + delta * sigma - (2 * old_sum + delta) * delta / n;
638 }
639
640 static int update_afs_statistics(struct afs_info *old_afsi, struct afs_info *new_afsi)
641 {
642 unsigned n;
643 int ret = get_num_admissible_files(&n);
644
645 if (ret < 0)
646 return ret;
647 assert(n);
648
649 statistics.last_played_qd = update_quadratic_deviation(n,
650 statistics.last_played_qd, old_afsi->last_played,
651 new_afsi->last_played, statistics.last_played_sum);
652 statistics.last_played_sum += new_afsi->last_played - old_afsi->last_played;
653
654 statistics.num_played_qd = update_quadratic_deviation(n,
655 statistics.num_played_qd, old_afsi->num_played,
656 new_afsi->num_played, statistics.num_played_sum);
657 statistics.num_played_sum += new_afsi->num_played - old_afsi->num_played;
658 return 1;
659 }
660
661 static int add_to_score_table(const struct osl_row *aft_row, long mood_score)
662 {
663 long score;
664 struct afs_info afsi;
665 int ret = get_afsi_of_row(aft_row, &afsi);
666
667 if (ret < 0)
668 return ret;
669 score = compute_score(&afsi, mood_score);
670 return score_add(aft_row, score);
671 }
672
673 static int delete_from_statistics_and_score_table(const struct osl_row *aft_row)
674 {
675 int ret = del_afs_statistics(aft_row);
676 if (ret < 0)
677 return ret;
678 return score_delete(aft_row);
679 }
680
681 /**
682 * Delete one entry from the statistics and from the score table.
683 *
684 * \param aft_row The audio file which is no longer admissible.
685 *
686 * \return Positive on success, negative on errors.
687 *
688 * \sa score_delete().
689 */
690 static int mood_delete_audio_file(const struct osl_row *aft_row)
691 {
692 int ret;
693
694 ret = row_belongs_to_score_table(aft_row, NULL);
695 if (ret < 0)
696 return ret;
697 if (!ret) /* not admissible, nothing to do */
698 return 1;
699 return delete_from_statistics_and_score_table(aft_row);
700 }
701
702 /**
703 * Compute the new score of an audio file wrt. the current mood.
704 *
705 * \param aft_row Determines the audio file.
706 * \param old_afsi The audio file selector info before updating.
707 *
708 * The \a old_afsi argument may be \p NULL which indicates that no changes to
709 * the audio file info were made.
710 *
711 * \return Positive on success, negative on errors.
712 */
713 static int mood_update_audio_file(const struct osl_row *aft_row,
714 struct afs_info *old_afsi)
715 {
716 long score, percent;
717 int ret, is_admissible, was_admissible = 0;
718 struct afs_info afsi;
719 unsigned rank;
720
721 if (!current_mood)
722 return 1; /* nothing to do */
723 ret = row_belongs_to_score_table(aft_row, &rank);
724 if (ret < 0)
725 return ret;
726 was_admissible = ret;
727 ret = compute_mood_score(aft_row, current_mood, &score);
728 if (ret < 0)
729 return ret;
730 is_admissible = (ret > 0);
731 if (!was_admissible && !is_admissible)
732 return 1;
733 if (was_admissible && !is_admissible)
734 return delete_from_statistics_and_score_table(aft_row);
735 if (!was_admissible && is_admissible) {
736 ret = add_afs_statistics(aft_row);
737 if (ret < 0)
738 return ret;
739 return add_to_score_table(aft_row, score);
740 }
741 /* update score */
742 ret = get_afsi_of_row(aft_row, &afsi);
743 if (ret < 0)
744 return ret;
745 if (old_afsi) {
746 ret = update_afs_statistics(old_afsi, &afsi);
747 if (ret < 0)
748 return ret;
749 }
750 score = compute_score(&afsi, score);
751 PARA_DEBUG_LOG("score: %li\n", score);
752 percent = (score + 100) / 3;
753 if (percent > 100)
754 percent = 100;
755 else if (percent < 0)
756 percent = 0;
757 PARA_DEBUG_LOG("moving from rank %u to %lu%%\n", rank, percent);
758 return score_update(aft_row, percent);
759 }
760
761 static void log_statistics(void)
762 {
763 unsigned n = statistics.num;
764
765 if (!n) {
766 PARA_NOTICE_LOG("no admissible files\n");
767 return;
768 }
769 PARA_INFO_LOG("last_played mean: %lli, last_played sigma: %llu\n",
770 (long long int)(statistics.last_played_sum / n),
771 (long long unsigned)int_sqrt(statistics.last_played_qd / n));
772 PARA_INFO_LOG("num_played mean: %lli, num_played sigma: %llu\n",
773 (long long int)statistics.num_played_sum / n,
774 (long long unsigned)int_sqrt(statistics.num_played_qd / n));
775 }
776
777 /**
778 * Close the current mood.
779 *
780 * Free all resources of the current mood which were allocated during
781 * mood_open().
782 */
783 void close_current_mood(void)
784 {
785 destroy_mood(current_mood);
786 current_mood = NULL;
787 memset(&statistics, 0, sizeof(statistics));
788 }
789
790 /**
791 * Change the current mood.
792 *
793 * \param mood_name The name of the mood to open.
794 *
795 * If \a mood_name is \a NULL, load the dummy mood that accepts every audio file
796 * and uses a scoring method based only on the \a last_played information.
797 *
798 * If there is already an open mood, it will be closed first.
799 *
800 * \return Positive on success, negative on errors. Loading the dummy mood
801 * always succeeds.
802 *
803 * \sa struct admissible_file_info, struct admissible_array, struct
804 * afs_info::last_played, mood_close().
805 */
806 int change_current_mood(char *mood_name)
807 {
808 int i, ret;
809 struct admissible_array aa = {
810 .size = 0,
811 .array = NULL
812 };
813
814 if (mood_name) {
815 struct mood *m;
816 struct osl_row *row;
817 struct osl_object obj = {
818 .data = mood_name,
819 .size = strlen(mood_name) + 1
820 };
821 ret = osl(osl_get_row(moods_table, BLOBCOL_NAME, &obj, &row));
822 if (ret < 0) {
823 PARA_NOTICE_LOG("no such mood: %s\n", mood_name);
824 return ret;
825 }
826 ret = load_mood(row, &m);
827 if (ret < 0)
828 return ret;
829 close_current_mood();
830 current_mood = m;
831 } else { /* load dummy mood */
832 close_current_mood();
833 current_mood = alloc_new_mood(NULL);
834 }
835 aa.m = current_mood;
836 PARA_NOTICE_LOG("computing statistics of admissible files\n");
837 ret = audio_file_loop(&aa, add_if_admissible);
838 if (ret < 0)
839 return ret;
840 log_statistics();
841 PARA_INFO_LOG("%d admissible files \n", statistics.num);
842 for (i = 0; i < statistics.num; i++) {
843 struct admissible_file_info *a = aa.array + i;
844 ret = add_to_score_table(a->aft_row, a->score);
845 if (ret < 0)
846 goto out;
847 }
848 PARA_NOTICE_LOG("loaded mood %s\n", mood_name? mood_name : "(dummy)");
849 ret = statistics.num;
850 out:
851 free(aa.array);
852 return ret;
853 }
854 /**
855 * Close and re-open the current mood.
856 *
857 * This function is used if changes to the audio file table or the
858 * attribute table were made that render the current list of admissible
859 * files useless. For example, if an attribute is removed from the
860 * attribute table, this function is called.
861 *
862 * \return Positive on success, negative on errors. If no mood is currently
863 * open, the function returns success.
864 *
865 * \sa mood_open(), mood_close().
866 */
867 static int reload_current_mood(void)
868 {
869 int ret;
870 char *mood_name = NULL;
871
872 if (!current_mood)
873 return 1;
874 PARA_NOTICE_LOG("reloading %s\n", current_mood->name?
875 current_mood->name : "(dummy)");
876 if (current_mood->name)
877 mood_name = para_strdup(current_mood->name);
878 close_current_mood();
879 ret = change_current_mood(mood_name);
880 free(mood_name);
881 return ret;
882 }
883
884 /**
885 * Notification callback for the moods table.
886 *
887 * \param event Type of the event just occurred.
888 * \param pb Unused.
889 * \param data Its type depends on the event.
890 *
891 * This function performs actions required due to the occurrence of the given
892 * event. Possible actions include reload of the current mood and update of the
893 * score of an audio file.
894 *
895 * \return Standard.
896 */
897 int moods_event_handler(enum afs_events event, __a_unused struct para_buffer *pb,
898 void *data)
899 {
900 int ret;
901
902 if (!current_mood)
903 return 0;
904 switch (event) {
905 /*
906 * The three blob events might change the set of admissible files,
907 * so we must reload the score list.
908 */
909 case BLOB_RENAME:
910 case BLOB_REMOVE:
911 case BLOB_ADD:
912 if (data == moods_table || data == playlists_table)
913 return 1; /* no reload necessary for these */
914 ret = clear_score_table();
915 if (ret < 0)
916 PARA_CRIT_LOG("clear score table returned %s\n",
917 para_strerror(-ret));
918 return reload_current_mood();
919 /* these also require reload of the score table */
920 case ATTRIBUTE_ADD:
921 case ATTRIBUTE_REMOVE:
922 case ATTRIBUTE_RENAME:
923 return reload_current_mood();
924 /* changes to the aft only require to re-examine the audio file */
925 case AFSI_CHANGE: {
926 struct afsi_change_event_data *aced = data;
927 return mood_update_audio_file(aced->aft_row, aced->old_afsi);
928 }
929 case AFHI_CHANGE:
930 case AUDIO_FILE_RENAME:
931 case AUDIO_FILE_ADD:
932 return mood_update_audio_file(data, NULL);
933 case AUDIO_FILE_REMOVE:
934 return mood_delete_audio_file(data);
935 default:
936 return 1;
937 }
938 }