mood.c: Fix documentation of int_sqrt().
[paraslash.git] / mood.c
1 /*
2 * Copyright (C) 2007 Andre Noll <maan@tuebingen.mpg.de>
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 #include <lopsub.h>
12
13 #include "para.h"
14 #include "error.h"
15 #include "string.h"
16 #include "afh.h"
17 #include "afs.h"
18 #include "list.h"
19 #include "ipc.h"
20 #include "mm.h"
21 #include "sideband.h"
22 #include "mood.h"
23 #include "sched.h"
24
25 /**
26 * Contains statistical data of the currently admissible audio files.
27 *
28 * It is used to assign normalized score values to each admissible audio file.
29 */
30 struct afs_statistics {
31 /** Sum of num played over all admissible files. */
32 int64_t num_played_sum;
33 /** Sum of last played times over all admissible files. */
34 int64_t last_played_sum;
35 /** Quadratic deviation of num played count. */
36 int64_t num_played_qd;
37 /** Quadratic deviation of last played time. */
38 int64_t last_played_qd;
39 /** Number of admissible files */
40 unsigned num;
41 };
42 static struct afs_statistics statistics;
43
44 /**
45 * Each line of the current mood corresponds to a mood_item.
46 */
47 struct mood_item {
48 /** The method this line is referring to. */
49 const struct mood_method *method;
50 /** The data structure computed by the mood parser. */
51 void *parser_data;
52 /** The given score value, or zero if none was given. */
53 int32_t score_arg;
54 /** Non-zero if random scoring was requested. */
55 int random_score;
56 /** Whether the "not" keyword was given in the mood line. */
57 int logical_not;
58 /** The position in the list of items. */
59 struct list_head mood_item_node;
60 };
61
62 /*
63 * Created from the mood definition by \ref change_current_mood().
64 *
65 * When a mood is opened, each line of its definition is investigated, and a
66 * corresponding mood item is produced. Each mood line starts with accept,
67 * deny, or score which determines the type of the mood line. For each such
68 * type a linked list is maintained whose entries are the mood items.
69 */
70 struct mood {
71 /** The name of this mood. */
72 char *name;
73 /** The list of mood items of type \p accept. */
74 struct list_head accept_list;
75 /** The list of mood items of type \p deny. */
76 struct list_head deny_list;
77 /** The list of mood items of type \p score. */
78 struct list_head score_list;
79 };
80
81 /*
82 * If current_mood is NULL then no mood is currently open. If
83 * current_mood->name is NULL, the dummy mood is currently open.
84 */
85 static struct mood *current_mood;
86
87 /*
88 * Find the position of the most-significant set bit.
89 *
90 * Copied and slightly adapted from the linux source tree, version 4.9.39
91 * (2017-07).
92 */
93 __a_const static uint32_t fls64(uint64_t v)
94 {
95 int n = 63;
96 const uint64_t ones = ~(uint64_t)0U;
97
98 if ((v & (ones << 32)) == 0) {
99 n -= 32;
100 v <<= 32;
101 }
102 if ((v & (ones << (64 - 16))) == 0) {
103 n -= 16;
104 v <<= 16;
105 }
106 if ((v & (ones << (64 - 8))) == 0) {
107 n -= 8;
108 v <<= 8;
109 }
110 if ((v & (ones << (64 - 4))) == 0) {
111 n -= 4;
112 v <<= 4;
113 }
114 if ((v & (ones << (64 - 2))) == 0) {
115 n -= 2;
116 v <<= 2;
117 }
118 if ((v & (ones << (64 - 1))) == 0)
119 n -= 1;
120 return n;
121 }
122
123 /*
124 * Compute the integer square root floor(sqrt(x)).
125 *
126 * Taken 2007 from the linux source tree.
127 */
128 __a_const static uint64_t int_sqrt(uint64_t x)
129 {
130 uint64_t op, res, one = 1;
131 op = x;
132 res = 0;
133
134 one = one << (fls64(x) & ~one);
135 while (one != 0) {
136 if (op >= res + one) {
137 op = op - (res + one);
138 res = res + 2 * one;
139 }
140 res /= 2;
141 one /= 4;
142 }
143 // PARA_NOTICE_LOG("sqrt(%llu) = %llu\n", x, res);
144 return res;
145 }
146
147 /*
148 * Returns true if row matches, false if it does not match. In any case score
149 * and score_arg_sum are set/increased accordingly.
150 */
151 static bool get_item_score(struct mood_item *item, const struct afs_info *afsi,
152 const struct afh_info *afhi, const char *path, long *score,
153 long *score_arg_sum)
154 {
155 int ret;
156 bool match = true;
157
158 *score_arg_sum += item->random_score? 100 : PARA_ABS(item->score_arg);
159 ret = 100;
160 if (item->method) {
161 ret = item->method->score_function(path, afsi, afhi,
162 item->parser_data);
163 if ((ret < 0 && !item->logical_not) || (ret >= 0 && item->logical_not))
164 match = false;
165 }
166 if (item->random_score)
167 *score = PARA_ABS(ret) * para_random(100);
168 else
169 *score = PARA_ABS(ret) * item->score_arg;
170 return match;
171 }
172
173 /* returns 1 if row admissible, 0 if not, negative on errors */
174 static int row_is_admissible(const struct osl_row *aft_row, struct mood *m,
175 long *scorep)
176 {
177 struct mood_item *item;
178 int ret;
179 bool match;
180 long score_arg_sum = 0, score = 0, item_score;
181 struct afs_info afsi;
182 struct afh_info afhi;
183 char *path;
184
185 if (!m)
186 return -E_NO_MOOD;
187 ret = get_afsi_of_row(aft_row, &afsi);
188 if (ret < 0)
189 return ret;
190 ret = get_afhi_of_row(aft_row, &afhi);
191 if (ret < 0)
192 return ret;
193 ret = get_audio_file_path_of_row(aft_row, &path);
194 if (ret < 0)
195 return ret;
196 /* reject audio file if it matches any entry in the deny list */
197 list_for_each_entry(item, &m->deny_list, mood_item_node) {
198 match = get_item_score(item, &afsi, &afhi, path, &item_score,
199 &score_arg_sum);
200 if (match) /* not admissible */
201 return 0;
202 score += item_score;
203 }
204 match = false;
205 list_for_each_entry(item, &m->accept_list, mood_item_node) {
206 ret = get_item_score(item, &afsi, &afhi, path, &item_score,
207 &score_arg_sum);
208 if (ret == 0)
209 continue;
210 match = true;
211 score += item_score;
212 }
213 /* reject if there is no matching entry in the accept list */
214 if (!match && !list_empty(&m->accept_list))
215 return 0;
216 list_for_each_entry(item, &m->score_list, mood_item_node) {
217 match = get_item_score(item, &afsi, &afhi, path, &item_score,
218 &score_arg_sum);
219 if (match)
220 score += item_score;
221 }
222 if (score_arg_sum)
223 score /= score_arg_sum;
224 *scorep = score;
225 return 1;
226 }
227
228 static void cleanup_list_entry(struct mood_item *item)
229 {
230 if (item->method && item->method->cleanup)
231 item->method->cleanup(item->parser_data);
232 else
233 free(item->parser_data);
234 list_del(&item->mood_item_node);
235 free(item);
236 }
237
238 static void destroy_mood(struct mood *m)
239 {
240 struct mood_item *tmp, *item;
241
242 if (!m)
243 return;
244 list_for_each_entry_safe(item, tmp, &m->accept_list, mood_item_node)
245 cleanup_list_entry(item);
246 list_for_each_entry_safe(item, tmp, &m->deny_list, mood_item_node)
247 cleanup_list_entry(item);
248 list_for_each_entry_safe(item, tmp, &m->score_list, mood_item_node)
249 cleanup_list_entry(item);
250 free(m->name);
251 free(m);
252 }
253
254 static struct mood *alloc_new_mood(const char *name)
255 {
256 struct mood *m = para_calloc(sizeof(struct mood));
257 if (name)
258 m->name = para_strdup(name);
259 INIT_LIST_HEAD(&m->accept_list);
260 INIT_LIST_HEAD(&m->deny_list);
261 INIT_LIST_HEAD(&m->score_list);
262 return m;
263 }
264
265 /** The different types of a mood line. */
266 enum mood_line_type {
267 /** Invalid. */
268 ML_INVALID,
269 /** Accept line. */
270 ML_ACCEPT,
271 /** Deny line. */
272 ML_DENY,
273 /** Score line. */
274 ML_SCORE
275 };
276
277 /** Data passed to the parser of a mood line. */
278 struct mood_line_parser_data {
279 /** The mood this mood line belongs to. */
280 struct mood *m;
281 /** The line number in the mood definition. */
282 unsigned line_num;
283 };
284
285 /*
286 * <accept [with score <score>] | deny [with score <score>] | score <score>>
287 * [if] [not] <mood_method> [options]
288 * <score> is either an integer or "random" which assigns a random score to
289 * all matching files
290 */
291 static int parse_mood_line(char *mood_line, void *data)
292 {
293 struct mood_line_parser_data *mlpd = data;
294 char **argv;
295 unsigned num_words;
296 char **w;
297 int i, ret;
298 enum mood_line_type mlt = ML_INVALID;
299 struct mood_item *mi = NULL;
300
301 mlpd->line_num++;
302 ret = create_argv(mood_line, " \t", &argv);
303 if (ret < 0)
304 return ret;
305 num_words = ret;
306 if (!num_words) /* empty line */
307 goto out;
308 w = argv;
309 if (**w == '#') /* comment */
310 goto out;
311 if (!strcmp(*w, "accept"))
312 mlt = ML_ACCEPT;
313 else if (!strcmp(*w, "deny"))
314 mlt = ML_DENY;
315 else if (!strcmp(*w, "score"))
316 mlt = ML_SCORE;
317 ret = -E_MOOD_SYNTAX;
318 if (mlt == ML_INVALID)
319 goto out;
320 mi = para_calloc(sizeof(struct mood_item));
321 if (mlt != ML_SCORE) {
322 ret = -E_MOOD_SYNTAX;
323 w++;
324 if (!*w)
325 goto out;
326 if (strcmp(*w, "with"))
327 goto check_for_if;
328 w++;
329 if (!*w)
330 goto out;
331 if (strcmp(*w, "score"))
332 goto out;
333 }
334 if (mlt == ML_SCORE || !strcmp(*w, "score")) {
335 ret = -E_MOOD_SYNTAX;
336 w++;
337 if (!*w)
338 goto out;
339 if (strcmp(*w, "random")) {
340 mi->random_score = 0;
341 ret = para_atoi32(*w, &mi->score_arg);
342 if (ret < 0)
343 goto out;
344 } else {
345 mi->random_score = 1;
346 if (!*(w + 1))
347 goto success; /* the line "score random" is valid */
348 }
349 } else
350 mi->score_arg = 0;
351 ret = -E_MOOD_SYNTAX;
352 w++;
353 if (!*w)
354 goto out;
355 check_for_if:
356 if (!strcmp(*w, "if")) {
357 ret = -E_MOOD_SYNTAX;
358 w++;
359 if (!*w)
360 goto out;
361 }
362 if (!strcmp(*w, "not")) {
363 ret = -E_MOOD_SYNTAX;
364 w++;
365 if (!*w)
366 goto out;
367 mi->logical_not = 1;
368 } else
369 mi->logical_not = 0;
370 for (i = 0; mood_methods[i].parser; i++) {
371 if (strcmp(*w, mood_methods[i].name))
372 continue;
373 break;
374 }
375 ret = -E_MOOD_SYNTAX;
376 if (!mood_methods[i].parser)
377 goto out;
378 ret = mood_methods[i].parser(num_words - 1 - (w - argv), w,
379 &mi->parser_data);
380 if (ret < 0)
381 goto out;
382 mi->method = &mood_methods[i];
383 success:
384 if (mlpd->m) {
385 if (mlt == ML_ACCEPT)
386 para_list_add(&mi->mood_item_node, &mlpd->m->accept_list);
387 else if (mlt == ML_DENY)
388 para_list_add(&mi->mood_item_node, &mlpd->m->deny_list);
389 else
390 para_list_add(&mi->mood_item_node, &mlpd->m->score_list);
391 }
392 PARA_DEBUG_LOG("%s entry added, method: %p\n", mlt == ML_ACCEPT? "accept" :
393 (mlt == ML_DENY? "deny" : "score"), mi->method);
394 ret = 1;
395 out:
396 free_argv(argv);
397 if (ret >= 0)
398 return ret;
399 if (mi) {
400 free(mi->parser_data);
401 free(mi);
402 }
403 return ret;
404 }
405
406 static int load_mood(const struct osl_row *mood_row, struct mood **m)
407 {
408 char *mood_name;
409 struct osl_object mood_def;
410 struct mood_line_parser_data mlpd = {.line_num = 0};
411 int ret;
412
413 *m = NULL;
414 ret = mood_get_name_and_def_by_row(mood_row, &mood_name, &mood_def);
415 if (ret < 0)
416 return ret;
417 if (!*mood_name)
418 return -E_DUMMY_ROW;
419 mlpd.m = alloc_new_mood(mood_name);
420 ret = for_each_line(FELF_READ_ONLY, mood_def.data, mood_def.size,
421 parse_mood_line, &mlpd);
422 osl_close_disk_object(&mood_def);
423 if (ret < 0) {
424 PARA_ERROR_LOG("unable to load mood %s: %s\n", mlpd.m->name,
425 para_strerror(-ret));
426 destroy_mood(mlpd.m);
427 return ret;
428 }
429 *m = mlpd.m;
430 return 1;
431 }
432
433 static int check_mood(struct osl_row *mood_row, void *data)
434 {
435 struct para_buffer *pb = data;
436 char *mood_name;
437 struct osl_object mood_def;
438 struct mood_line_parser_data mlpd = {.line_num = 0};
439
440 int ret = mood_get_name_and_def_by_row(mood_row, &mood_name, &mood_def);
441
442 if (ret < 0) {
443 para_printf(pb, "cannot read mood\n");
444 return ret;
445 }
446 if (!*mood_name) /* ignore dummy row */
447 goto out;
448 para_printf(pb, "checking mood %s...\n", mood_name);
449 ret = for_each_line(FELF_READ_ONLY, mood_def.data, mood_def.size,
450 parse_mood_line, &mlpd);
451 if (ret < 0)
452 para_printf(pb, "mood %s: error in line %u: %s\n", mood_name,
453 mlpd.line_num, para_strerror(-ret));
454 ret = 1; /* don't fail the loop on invalid mood definitions */
455 out:
456 osl_close_disk_object(&mood_def);
457 return ret;
458 }
459
460 /**
461 * Check all moods for syntax errors.
462 *
463 * \param aca Only ->pbout is used for diagnostics.
464 *
465 * \return Negative on fatal errors. Inconsistent mood definitions are not
466 * considered an error.
467 */
468 int mood_check_callback(struct afs_callback_arg *aca)
469 {
470 para_printf(&aca->pbout, "checking moods...\n");
471 return osl(osl_rbtree_loop(moods_table, BLOBCOL_ID, &aca->pbout,
472 check_mood));
473 }
474
475 static int64_t normalized_value(int64_t x, int64_t n, int64_t sum, int64_t qd)
476 {
477 if (!n || !qd)
478 return 0;
479 return 100 * (n * x - sum) / (int64_t)int_sqrt(n) / (int64_t)int_sqrt(qd);
480 }
481
482 static long compute_score(struct afs_info *afsi, long mood_score)
483 {
484 mood_score -= normalized_value(afsi->num_played, statistics.num,
485 statistics.num_played_sum, statistics.num_played_qd);
486 mood_score -= normalized_value(afsi->last_played, statistics.num,
487 statistics.last_played_sum, statistics.last_played_qd);
488 return mood_score / 3;
489 }
490
491 static int add_afs_statistics(const struct osl_row *row)
492 {
493 uint64_t n, x, s, q;
494 struct afs_info afsi;
495 int ret;
496
497 ret = get_afsi_of_row(row, &afsi);
498 if (ret < 0)
499 return ret;
500 n = statistics.num;
501 x = afsi.last_played;
502 s = statistics.last_played_sum;
503 if (n > 0) {
504 q = (x > s / n)? x - s / n : s / n - x;
505 statistics.last_played_qd += q * q * n / (n + 1);
506 }
507 statistics.last_played_sum += x;
508
509 x = afsi.num_played;
510 s = statistics.num_played_sum;
511 if (n > 0) {
512 q = (x > s / n)? x - s / n : s / n - x;
513 statistics.num_played_qd += q * q * n / (n + 1);
514 }
515 statistics.num_played_sum += x;
516 statistics.num++;
517 return 1;
518 }
519
520 static int del_afs_statistics(const struct osl_row *row)
521 {
522 uint64_t n, s, q, a, new_s;
523 struct afs_info afsi;
524 int ret;
525 ret = get_afsi_of_row(row, &afsi);
526 if (ret < 0)
527 return ret;
528 n = statistics.num;
529 assert(n);
530 if (n == 1) {
531 memset(&statistics, 0, sizeof(statistics));
532 return 1;
533 }
534
535 s = statistics.last_played_sum;
536 q = statistics.last_played_qd;
537 a = afsi.last_played;
538 new_s = s - a;
539 statistics.last_played_sum = new_s;
540 statistics.last_played_qd = q + s * s / n - a * a
541 - new_s * new_s / (n - 1);
542
543 s = statistics.num_played_sum;
544 q = statistics.num_played_qd;
545 a = afsi.num_played;
546 new_s = s - a;
547 statistics.num_played_sum = new_s;
548 statistics.num_played_qd = q + s * s / n - a * a
549 - new_s * new_s / (n - 1);
550
551 statistics.num--;
552 return 1;
553 }
554
555 /*
556 * At mood open time we determine the set of admissible files for the given
557 * mood. The mood score of each admissible file is computed by adding up all
558 * mood item scores. Next, we update the afs statistics and append a struct
559 * admissible_file_info to a temporary array.
560 *
561 * When all files have been processed in this way, the final score of each
562 * admissible file is computed by adding the dynamic score (which depends on
563 * the afs_statistics and the current time) to the mood score. Finally, all
564 * audio files in the temporary array are added to the score table and the
565 * array is freed.
566 */
567 struct admissible_file_info
568 {
569 /** The admissible audio file. */
570 struct osl_row *aft_row;
571 /** Its score. */
572 long score;
573 };
574
575 /** The temporary array of admissible files. */
576 struct admissible_array {
577 /** Files are admissible wrt. this mood. */
578 struct mood *m;
579 /** The size of the array */
580 unsigned size;
581 /** Pointer to the array of admissible files. */
582 struct admissible_file_info *array;
583 };
584
585 /**
586 * Add an entry to the array of admissible files.
587 *
588 * \param aft_row The audio file to be added.
589 * \param private_data Pointer to a struct admissible_file_info.
590 *
591 * \return 1 if row admissible, 0 if not, negative on errors.
592 */
593 static int add_if_admissible(struct osl_row *aft_row, void *data)
594 {
595 struct admissible_array *aa = data;
596 int ret;
597 long score = 0;
598
599 ret = row_is_admissible(aft_row, aa->m, &score);
600 if (ret <= 0)
601 return ret;
602 if (statistics.num >= aa->size) {
603 aa->size *= 2;
604 aa->size += 100;
605 aa->array = para_realloc(aa->array,
606 aa->size * sizeof(struct admissible_file_info));
607 }
608 aa->array[statistics.num].aft_row = aft_row;
609 aa->array[statistics.num].score = score;
610 ret = add_afs_statistics(aft_row);
611 if (ret < 0)
612 return ret;
613 return 1;
614 }
615
616 /**
617 * Compute the new quadratic deviation in case one element changes.
618 *
619 * \param n Number of elements.
620 * \param old_qd The quadratic deviation before the change.
621 * \param old_val The value that was replaced.
622 * \param new_val The replacement value.
623 * \param old_sum The sum of all elements before the update.
624 *
625 * \return The new quadratic deviation resulting from replacing old_val
626 * by new_val.
627 *
628 * Given n real numbers a_1, ..., a_n, their sum S = a_1 + ... + a_n,
629 * their quadratic deviation
630 *
631 * q = (a_1 - S/n)^2 + ... + (a_n - S/n)^2,
632 *
633 * and a real number b, the quadratic deviation q' of a_1,...a_{n-1}, b (ie.
634 * the last number a_n was replaced by b) may be computed in O(1) time in terms
635 * of n, q, a_n, b, and S as
636 *
637 * q' = q + d * s - (2 * S + d) * d / n
638 * = q + d * (s - 2 * S / n - d /n),
639 *
640 * where d = b - a_n, and s = b + a_n.
641 *
642 * Example: n = 3, a_1 = 3, a_2 = 5, a_3 = 7, b = 10. Then S = 15, q = 8, d = 3,
643 * s = 17, so
644 *
645 * q + d * s - (2 * S + d) * d / n = 8 + 51 - 33 = 26,
646 *
647 * which equals q' = (3 - 6)^2 + (5 - 6)^2 + (10 - 6)^2.
648 *
649 */
650 _static_inline_ int64_t update_quadratic_deviation(int64_t n, int64_t old_qd,
651 int64_t old_val, int64_t new_val, int64_t old_sum)
652 {
653 int64_t delta = new_val - old_val;
654 int64_t sigma = new_val + old_val;
655 return old_qd + delta * (sigma - 2 * old_sum / n - delta / n);
656 }
657
658 static int update_afs_statistics(struct afs_info *old_afsi,
659 struct afs_info *new_afsi)
660 {
661 unsigned n;
662 int ret = get_num_admissible_files(&n);
663
664 if (ret < 0)
665 return ret;
666 assert(n);
667
668 statistics.last_played_qd = update_quadratic_deviation(n,
669 statistics.last_played_qd, old_afsi->last_played,
670 new_afsi->last_played, statistics.last_played_sum);
671 statistics.last_played_sum += new_afsi->last_played - old_afsi->last_played;
672
673 statistics.num_played_qd = update_quadratic_deviation(n,
674 statistics.num_played_qd, old_afsi->num_played,
675 new_afsi->num_played, statistics.num_played_sum);
676 statistics.num_played_sum += new_afsi->num_played - old_afsi->num_played;
677 return 1;
678 }
679
680 static int add_to_score_table(const struct osl_row *aft_row, long mood_score)
681 {
682 long score;
683 struct afs_info afsi;
684 int ret = get_afsi_of_row(aft_row, &afsi);
685
686 if (ret < 0)
687 return ret;
688 score = compute_score(&afsi, mood_score);
689 return score_add(aft_row, score);
690 }
691
692 static int delete_from_statistics_and_score_table(const struct osl_row *aft_row)
693 {
694 int ret = del_afs_statistics(aft_row);
695 if (ret < 0)
696 return ret;
697 return score_delete(aft_row);
698 }
699
700 /**
701 * Delete one entry from the statistics and from the score table.
702 *
703 * \param aft_row The audio file which is no longer admissible.
704 *
705 * \return Positive on success, negative on errors.
706 *
707 * \sa \ref score_delete().
708 */
709 static int mood_delete_audio_file(const struct osl_row *aft_row)
710 {
711 int ret;
712
713 ret = row_belongs_to_score_table(aft_row, NULL);
714 if (ret < 0)
715 return ret;
716 if (!ret) /* not admissible, nothing to do */
717 return 1;
718 return delete_from_statistics_and_score_table(aft_row);
719 }
720
721 /**
722 * Compute the new score of an audio file wrt. the current mood.
723 *
724 * \param aft_row Determines the audio file.
725 * \param old_afsi The audio file selector info before updating.
726 *
727 * The \a old_afsi argument may be \p NULL which indicates that no changes to
728 * the audio file info were made.
729 *
730 * \return Positive on success, negative on errors.
731 */
732 static int mood_update_audio_file(const struct osl_row *aft_row,
733 struct afs_info *old_afsi)
734 {
735 long score, percent;
736 int ret, is_admissible, was_admissible = 0;
737 struct afs_info afsi;
738 unsigned rank;
739
740 if (!current_mood)
741 return 1; /* nothing to do */
742 ret = row_belongs_to_score_table(aft_row, &rank);
743 if (ret < 0)
744 return ret;
745 was_admissible = ret;
746 ret = row_is_admissible(aft_row, current_mood, &score);
747 if (ret < 0)
748 return ret;
749 is_admissible = (ret > 0);
750 if (!was_admissible && !is_admissible)
751 return 1;
752 if (was_admissible && !is_admissible)
753 return delete_from_statistics_and_score_table(aft_row);
754 if (!was_admissible && is_admissible) {
755 ret = add_afs_statistics(aft_row);
756 if (ret < 0)
757 return ret;
758 return add_to_score_table(aft_row, score);
759 }
760 /* update score */
761 ret = get_afsi_of_row(aft_row, &afsi);
762 if (ret < 0)
763 return ret;
764 if (old_afsi) {
765 ret = update_afs_statistics(old_afsi, &afsi);
766 if (ret < 0)
767 return ret;
768 }
769 score = compute_score(&afsi, score);
770 PARA_DEBUG_LOG("score: %li\n", score);
771 percent = (score + 100) / 3;
772 if (percent > 100)
773 percent = 100;
774 else if (percent < 0)
775 percent = 0;
776 PARA_DEBUG_LOG("moving from rank %u to %li%%\n", rank, percent);
777 return score_update(aft_row, percent);
778 }
779
780 static void log_statistics(void)
781 {
782 unsigned n = statistics.num;
783 int mean_days, sigma_days;
784 /*
785 * We can not use the "now" pointer from sched.c here because we are
786 * called before schedule(), which initializes "now".
787 */
788 struct timeval rnow;
789
790 assert(current_mood);
791 PARA_NOTICE_LOG("loaded mood %s\n", current_mood->name?
792 current_mood->name : "(dummy)");
793 if (!n) {
794 PARA_WARNING_LOG("no admissible files\n");
795 return;
796 }
797 PARA_NOTICE_LOG("%u admissible files\n", statistics.num);
798 clock_get_realtime(&rnow);
799 mean_days = (rnow.tv_sec - statistics.last_played_sum / n) / 3600 / 24;
800 sigma_days = int_sqrt(statistics.last_played_qd / n) / 3600 / 24;
801 PARA_NOTICE_LOG("last_played mean/sigma: %d/%d days\n", mean_days, sigma_days);
802 PARA_NOTICE_LOG("num_played mean/sigma: %llu/%llu\n",
803 (long long unsigned)statistics.num_played_sum / n,
804 (long long unsigned)int_sqrt(statistics.num_played_qd / n));
805 }
806
807 /**
808 * Close the current mood.
809 *
810 * Frees all resources of the current mood.
811 */
812 void close_current_mood(void)
813 {
814 destroy_mood(current_mood);
815 current_mood = NULL;
816 memset(&statistics, 0, sizeof(statistics));
817 }
818
819 /**
820 * Change the current mood.
821 *
822 * \param mood_name The name of the mood to open.
823 *
824 * If \a mood_name is \a NULL, load the dummy mood that accepts every audio file
825 * and uses a scoring method based only on the \a last_played information.
826 *
827 * If there is already an open mood, it will be closed first.
828 *
829 * \return Positive on success, negative on errors. Loading the dummy mood
830 * always succeeds.
831 *
832 * \sa struct \ref afs_info::last_played.
833 */
834 int change_current_mood(const char *mood_name)
835 {
836 int i, ret;
837 struct admissible_array aa = {
838 .size = 0,
839 .array = NULL
840 };
841
842 if (mood_name) {
843 struct mood *m;
844 struct osl_row *row;
845 struct osl_object obj = {
846 .data = (char *)mood_name,
847 .size = strlen(mood_name) + 1
848 };
849 ret = osl(osl_get_row(moods_table, BLOBCOL_NAME, &obj, &row));
850 if (ret < 0) {
851 PARA_NOTICE_LOG("no such mood: %s\n", mood_name);
852 return ret;
853 }
854 ret = load_mood(row, &m);
855 if (ret < 0)
856 return ret;
857 close_current_mood();
858 current_mood = m;
859 } else { /* load dummy mood */
860 close_current_mood();
861 current_mood = alloc_new_mood(NULL);
862 }
863 aa.m = current_mood;
864 PARA_NOTICE_LOG("computing statistics of admissible files\n");
865 ret = audio_file_loop(&aa, add_if_admissible);
866 if (ret < 0)
867 return ret;
868 for (i = 0; i < statistics.num; i++) {
869 struct admissible_file_info *a = aa.array + i;
870 ret = add_to_score_table(a->aft_row, a->score);
871 if (ret < 0)
872 goto out;
873 }
874 log_statistics();
875 ret = statistics.num;
876 out:
877 free(aa.array);
878 return ret;
879 }
880
881 /*
882 * Close and re-open the current mood.
883 *
884 * This function is called on events which render the current list of
885 * admissible files useless, for example if an attribute is removed from the
886 * attribute table.
887 *
888 * If no mood is currently open, the function returns success.
889 */
890 static int reload_current_mood(void)
891 {
892 int ret;
893 char *mood_name = NULL;
894
895 ret = clear_score_table();
896 if (ret < 0)
897 return ret;
898 if (!current_mood)
899 return 1;
900 PARA_NOTICE_LOG("reloading %s\n", current_mood->name?
901 current_mood->name : "(dummy)");
902 if (current_mood->name)
903 mood_name = para_strdup(current_mood->name);
904 close_current_mood();
905 ret = change_current_mood(mood_name);
906 free(mood_name);
907 return ret;
908 }
909
910 /**
911 * Notification callback for the moods table.
912 *
913 * \param event Type of the event just occurred.
914 * \param pb Unused.
915 * \param data Its type depends on the event.
916 *
917 * This function performs actions required due to the occurrence of the given
918 * event. Possible actions include reload of the current mood and update of the
919 * score of an audio file.
920 *
921 * \return Standard.
922 */
923 int moods_event_handler(enum afs_events event, __a_unused struct para_buffer *pb,
924 void *data)
925 {
926 if (!current_mood)
927 return 0;
928 switch (event) {
929 /*
930 * The three blob events might change the set of admissible files,
931 * so we must reload the score list.
932 */
933 case BLOB_RENAME:
934 case BLOB_REMOVE:
935 case BLOB_ADD:
936 if (data == moods_table || data == playlists_table)
937 return 1; /* no reload necessary for these */
938 return reload_current_mood();
939 /* these also require reload of the score table */
940 case ATTRIBUTE_ADD:
941 case ATTRIBUTE_REMOVE:
942 case ATTRIBUTE_RENAME:
943 return reload_current_mood();
944 /* changes to the aft only require to re-examine the audio file */
945 case AFSI_CHANGE: {
946 struct afsi_change_event_data *aced = data;
947 return mood_update_audio_file(aced->aft_row, aced->old_afsi);
948 }
949 case AFHI_CHANGE:
950 case AUDIO_FILE_RENAME:
951 case AUDIO_FILE_ADD:
952 return mood_update_audio_file(data, NULL);
953 case AUDIO_FILE_REMOVE:
954 return mood_delete_audio_file(data);
955 default:
956 return 1;
957 }
958 }