Merge branch 'refs/heads/t/mp'
[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 "mm.h"
20 #include "mood.h"
21
22 /*
23 * Mood parser API. It's overkill to have an own header file for
24 * these declarations as they are only needed in this .c file.
25 */
26 struct mp_context;
27 int mp_init(const char *definition, int nbytes, struct mp_context **result,
28 char **errmsg);
29 bool mp_eval_row(const struct osl_row *aft_row, struct mp_context *ctx);
30 void mp_shutdown(struct mp_context *ctx);
31
32 /**
33 * Contains statistical data of the currently admissible audio files.
34 *
35 * It is used to assign normalized score values to each admissible audio file.
36 */
37 struct afs_statistics {
38 /** Sum of num played over all admissible files. */
39 int64_t num_played_sum;
40 /** Sum of last played times over all admissible files. */
41 int64_t last_played_sum;
42 /** Quadratic deviation of num played count. */
43 int64_t num_played_qd;
44 /** Quadratic deviation of last played time. */
45 int64_t last_played_qd;
46 /** Number of admissible files */
47 unsigned num;
48 };
49 static struct afs_statistics statistics;
50
51 /**
52 * Each line of the current mood corresponds to a mood_item.
53 */
54 struct mood_item {
55 /** The method this line is referring to. */
56 const struct mood_method *method;
57 /** The data structure computed by the mood parser. */
58 void *parser_data;
59 /** The given score value, or zero if none was given. */
60 int32_t score_arg;
61 /** Non-zero if random scoring was requested. */
62 int random_score;
63 /** Whether the "not" keyword was given in the mood line. */
64 int logical_not;
65 /** The position in the list of items. */
66 struct list_head mood_item_node;
67 };
68
69 /*
70 * Created from the mood definition by \ref change_current_mood().
71 *
72 * When a mood is opened, each line of its definition is investigated, and a
73 * corresponding mood item is produced. Each mood line starts with accept,
74 * deny, or score which determines the type of the mood line. For each such
75 * type a linked list is maintained whose entries are the mood items.
76 */
77 struct mood {
78 /** The name of this mood. */
79 char *name;
80 /** The list of mood items of type \p accept. */
81 struct list_head accept_list;
82 /** The list of mood items of type \p deny. */
83 struct list_head deny_list;
84 /** The list of mood items of type \p score. */
85 struct list_head score_list;
86 /* Only used for version 2 moods. */
87 struct mp_context *parser_context;
88 };
89
90 /*
91 * If current_mood is NULL then no mood is currently open. If
92 * current_mood->name is NULL, the dummy mood is currently open.
93 */
94 static struct mood *current_mood;
95
96 /*
97 * Find the position of the most-significant set bit.
98 *
99 * Copied and slightly adapted from the linux source tree, version 4.9.39
100 * (2017-07).
101 */
102 __a_const static uint32_t fls64(uint64_t v)
103 {
104 int n = 63;
105 const uint64_t ones = ~(uint64_t)0U;
106
107 if ((v & (ones << 32)) == 0) {
108 n -= 32;
109 v <<= 32;
110 }
111 if ((v & (ones << (64 - 16))) == 0) {
112 n -= 16;
113 v <<= 16;
114 }
115 if ((v & (ones << (64 - 8))) == 0) {
116 n -= 8;
117 v <<= 8;
118 }
119 if ((v & (ones << (64 - 4))) == 0) {
120 n -= 4;
121 v <<= 4;
122 }
123 if ((v & (ones << (64 - 2))) == 0) {
124 n -= 2;
125 v <<= 2;
126 }
127 if ((v & (ones << (64 - 1))) == 0)
128 n -= 1;
129 return n;
130 }
131
132 /*
133 * Compute the integer square root floor(sqrt(x)).
134 *
135 * Taken 2007 from the linux source tree.
136 */
137 __a_const static uint64_t int_sqrt(uint64_t x)
138 {
139 uint64_t op = x, res = 0, one = 1;
140
141 one = one << (fls64(x) & ~one);
142 while (one != 0) {
143 if (op >= res + one) {
144 op = op - (res + one);
145 res = res + 2 * one;
146 }
147 res /= 2;
148 one /= 4;
149 }
150 return res;
151 }
152
153 /*
154 * Returns true if row matches, false if it does not match. In any case score
155 * and score_arg_sum are set/increased accordingly.
156 */
157 static bool get_item_score(struct mood_item *item, const struct afs_info *afsi,
158 const struct afh_info *afhi, const char *path, long *score,
159 long *score_arg_sum)
160 {
161 int ret;
162 bool match = true;
163
164 *score_arg_sum += item->random_score? 100 : PARA_ABS(item->score_arg);
165 ret = 100;
166 if (item->method) {
167 ret = item->method->score_function(path, afsi, afhi,
168 item->parser_data);
169 if ((ret < 0 && !item->logical_not) || (ret >= 0 && item->logical_not))
170 match = false;
171 }
172 if (item->random_score)
173 *score = PARA_ABS(ret) * para_random(100);
174 else
175 *score = PARA_ABS(ret) * item->score_arg;
176 return match;
177 }
178
179 /* returns 1 if row admissible, 0 if not, negative on errors */
180 static int row_is_admissible(const struct osl_row *aft_row, struct mood *m,
181 long *scorep)
182 {
183 struct mood_item *item;
184 int ret;
185 bool match;
186 long score_arg_sum = 0, score = 0, item_score;
187 struct afs_info afsi;
188 struct afh_info afhi;
189 char *path;
190
191 if (!m)
192 return -E_NO_MOOD;
193 if (m->parser_context) {
194 *scorep = 0;
195 return mp_eval_row(aft_row, m->parser_context);
196 }
197 ret = get_afsi_of_row(aft_row, &afsi);
198 if (ret < 0)
199 return ret;
200 ret = get_afhi_of_row(aft_row, &afhi);
201 if (ret < 0)
202 return ret;
203 ret = get_audio_file_path_of_row(aft_row, &path);
204 if (ret < 0)
205 return ret;
206 /* reject audio file if it matches any entry in the deny list */
207 list_for_each_entry(item, &m->deny_list, mood_item_node) {
208 match = get_item_score(item, &afsi, &afhi, path, &item_score,
209 &score_arg_sum);
210 if (match) /* not admissible */
211 return 0;
212 score += item_score;
213 }
214 match = false;
215 list_for_each_entry(item, &m->accept_list, mood_item_node) {
216 ret = get_item_score(item, &afsi, &afhi, path, &item_score,
217 &score_arg_sum);
218 if (ret == 0)
219 continue;
220 match = true;
221 score += item_score;
222 }
223 /* reject if there is no matching entry in the accept list */
224 if (!match && !list_empty(&m->accept_list))
225 return 0;
226 list_for_each_entry(item, &m->score_list, mood_item_node) {
227 match = get_item_score(item, &afsi, &afhi, path, &item_score,
228 &score_arg_sum);
229 if (match)
230 score += item_score;
231 }
232 if (score_arg_sum)
233 score /= score_arg_sum;
234 *scorep = score;
235 return 1;
236 }
237
238 static void cleanup_list_entry(struct mood_item *item)
239 {
240 if (item->method && item->method->cleanup)
241 item->method->cleanup(item->parser_data);
242 else
243 free(item->parser_data);
244 list_del(&item->mood_item_node);
245 free(item);
246 }
247
248 static void destroy_mood(struct mood *m)
249 {
250 struct mood_item *tmp, *item;
251
252 if (!m)
253 return;
254 list_for_each_entry_safe(item, tmp, &m->accept_list, mood_item_node)
255 cleanup_list_entry(item);
256 list_for_each_entry_safe(item, tmp, &m->deny_list, mood_item_node)
257 cleanup_list_entry(item);
258 list_for_each_entry_safe(item, tmp, &m->score_list, mood_item_node)
259 cleanup_list_entry(item);
260 free(m->name);
261 mp_shutdown(m->parser_context);
262 free(m);
263 }
264
265 static struct mood *alloc_new_mood(const char *name)
266 {
267 struct mood *m = para_calloc(sizeof(struct mood));
268 if (name)
269 m->name = para_strdup(name);
270 INIT_LIST_HEAD(&m->accept_list);
271 INIT_LIST_HEAD(&m->deny_list);
272 INIT_LIST_HEAD(&m->score_list);
273 return m;
274 }
275
276 /** The different types of a mood line. */
277 enum mood_line_type {
278 /** Invalid. */
279 ML_INVALID,
280 /** Accept line. */
281 ML_ACCEPT,
282 /** Deny line. */
283 ML_DENY,
284 /** Score line. */
285 ML_SCORE
286 };
287
288 /** Data passed to the parser of a mood line. */
289 struct mood_line_parser_data {
290 /** The mood this mood line belongs to. */
291 struct mood *m;
292 /** The line number in the mood definition. */
293 unsigned line_num;
294 };
295
296 /*
297 * <accept [with score <score>] | deny [with score <score>] | score <score>>
298 * [if] [not] <mood_method> [options]
299 * <score> is either an integer or "random" which assigns a random score to
300 * all matching files
301 */
302 static int parse_mood_line(char *mood_line, void *data)
303 {
304 struct mood_line_parser_data *mlpd = data;
305 char **argv;
306 unsigned num_words;
307 char **w;
308 int i, ret;
309 enum mood_line_type mlt = ML_INVALID;
310 struct mood_item *mi = NULL;
311
312 mlpd->line_num++;
313 ret = create_argv(mood_line, " \t", &argv);
314 if (ret < 0)
315 return ret;
316 num_words = ret;
317 if (!num_words) /* empty line */
318 goto out;
319 w = argv;
320 if (**w == '#') /* comment */
321 goto out;
322 if (!strcmp(*w, "accept"))
323 mlt = ML_ACCEPT;
324 else if (!strcmp(*w, "deny"))
325 mlt = ML_DENY;
326 else if (!strcmp(*w, "score"))
327 mlt = ML_SCORE;
328 ret = -E_MOOD_SYNTAX;
329 if (mlt == ML_INVALID)
330 goto out;
331 mi = para_calloc(sizeof(struct mood_item));
332 if (mlt != ML_SCORE) {
333 ret = -E_MOOD_SYNTAX;
334 w++;
335 if (!*w)
336 goto out;
337 if (strcmp(*w, "with"))
338 goto check_for_if;
339 w++;
340 if (!*w)
341 goto out;
342 if (strcmp(*w, "score"))
343 goto out;
344 }
345 if (mlt == ML_SCORE || !strcmp(*w, "score")) {
346 ret = -E_MOOD_SYNTAX;
347 w++;
348 if (!*w)
349 goto out;
350 if (strcmp(*w, "random")) {
351 mi->random_score = 0;
352 ret = para_atoi32(*w, &mi->score_arg);
353 if (ret < 0)
354 goto out;
355 } else {
356 mi->random_score = 1;
357 if (!*(w + 1))
358 goto success; /* the line "score random" is valid */
359 }
360 } else
361 mi->score_arg = 0;
362 ret = -E_MOOD_SYNTAX;
363 w++;
364 if (!*w)
365 goto out;
366 check_for_if:
367 if (!strcmp(*w, "if")) {
368 ret = -E_MOOD_SYNTAX;
369 w++;
370 if (!*w)
371 goto out;
372 }
373 if (!strcmp(*w, "not")) {
374 ret = -E_MOOD_SYNTAX;
375 w++;
376 if (!*w)
377 goto out;
378 mi->logical_not = 1;
379 } else
380 mi->logical_not = 0;
381 for (i = 0; mood_methods[i].parser; i++) {
382 if (strcmp(*w, mood_methods[i].name))
383 continue;
384 break;
385 }
386 ret = -E_MOOD_SYNTAX;
387 if (!mood_methods[i].parser)
388 goto out;
389 ret = mood_methods[i].parser(num_words - 1 - (w - argv), w,
390 &mi->parser_data);
391 if (ret < 0)
392 goto out;
393 mi->method = &mood_methods[i];
394 success:
395 if (mlpd->m) {
396 if (mlt == ML_ACCEPT)
397 para_list_add(&mi->mood_item_node, &mlpd->m->accept_list);
398 else if (mlt == ML_DENY)
399 para_list_add(&mi->mood_item_node, &mlpd->m->deny_list);
400 else
401 para_list_add(&mi->mood_item_node, &mlpd->m->score_list);
402 }
403 PARA_DEBUG_LOG("%s entry added, method: %p\n", mlt == ML_ACCEPT? "accept" :
404 (mlt == ML_DENY? "deny" : "score"), mi->method);
405 ret = 1;
406 out:
407 free_argv(argv);
408 if (mi && (ret < 0 || !mlpd->m)) { /* mi was not added to any list */
409 free(mi->parser_data);
410 free(mi);
411 }
412 return ret;
413 }
414
415 static int load_mood(const struct osl_row *mood_row, struct mood **m,
416 char **errmsg)
417 {
418 char *mood_name;
419 struct osl_object mood_def;
420 struct mood_line_parser_data mlpd = {.line_num = 0};
421 int ret;
422
423 *m = NULL;
424 ret = mood_get_name_and_def_by_row(mood_row, &mood_name, &mood_def);
425 if (ret < 0)
426 return ret;
427 if (!*mood_name)
428 return -E_DUMMY_ROW;
429 mlpd.m = alloc_new_mood(mood_name);
430 ret = for_each_line(FELF_READ_ONLY, mood_def.data, mood_def.size,
431 parse_mood_line, &mlpd);
432 if (ret < 0) {
433 PARA_INFO_LOG("opening version 2 mood %s\n", mlpd.m->name);
434 ret = mp_init(mood_def.data, mood_def.size, &mlpd.m->parser_context,
435 errmsg);
436 if (ret < 0)
437 destroy_mood(mlpd.m);
438 } else {
439 PARA_WARNING_LOG("loaded version 1 mood %s\n", mlpd.m->name);
440 PARA_WARNING_LOG("please convert to version 2\n");
441 ret = 1;
442 }
443 osl_close_disk_object(&mood_def);
444 if (ret >= 0)
445 *m = mlpd.m;
446 return ret;
447 }
448
449 static int check_mood(struct osl_row *mood_row, void *data)
450 {
451 struct para_buffer *pb = data;
452 char *mood_name;
453 struct osl_object mood_def;
454 struct mood_line_parser_data mlpd = {.line_num = 0};
455
456 int ret = mood_get_name_and_def_by_row(mood_row, &mood_name, &mood_def);
457
458 if (ret < 0) {
459 para_printf(pb, "cannot read mood\n");
460 return ret;
461 }
462 if (!*mood_name) /* ignore dummy row */
463 goto out;
464 ret = for_each_line(FELF_READ_ONLY, mood_def.data, mood_def.size,
465 parse_mood_line, &mlpd);
466 if (ret < 0) {
467 char *errmsg;
468 struct mood *m = alloc_new_mood("check");
469 ret = mp_init(mood_def.data, mood_def.size, &m->parser_context,
470 &errmsg);
471 if (ret < 0) {
472 para_printf(pb, "%s: %s\n", mood_name, errmsg);
473 free(errmsg);
474 para_printf(pb, "%s\n", para_strerror(-ret));
475 } else
476 destroy_mood(m);
477 } else {
478 para_printf(pb, "%s: v1 mood, please convert to v2\n",
479 mood_name);
480
481 }
482 ret = 1; /* don't fail the loop on invalid mood definitions */
483 out:
484 osl_close_disk_object(&mood_def);
485 return ret;
486 }
487
488 /**
489 * Check all moods for syntax errors.
490 *
491 * \param aca Only ->pbout is used for diagnostics.
492 *
493 * \return Negative on fatal errors. Inconsistent mood definitions are not
494 * considered an error.
495 */
496 int mood_check_callback(struct afs_callback_arg *aca)
497 {
498 para_printf(&aca->pbout, "checking moods...\n");
499 return osl(osl_rbtree_loop(moods_table, BLOBCOL_ID, &aca->pbout,
500 check_mood));
501 }
502
503 static int64_t normalized_value(int64_t x, int64_t n, int64_t sum, int64_t qd)
504 {
505 if (!n || !qd)
506 return 0;
507 return 100 * (n * x - sum) / (int64_t)int_sqrt(n) / (int64_t)int_sqrt(qd);
508 }
509
510 static long compute_score(struct afs_info *afsi, long mood_score)
511 {
512 mood_score -= normalized_value(afsi->num_played, statistics.num,
513 statistics.num_played_sum, statistics.num_played_qd);
514 mood_score -= normalized_value(afsi->last_played, statistics.num,
515 statistics.last_played_sum, statistics.last_played_qd);
516 return mood_score / 3;
517 }
518
519 static int add_afs_statistics(const struct osl_row *row)
520 {
521 uint64_t n, x, s, q;
522 struct afs_info afsi;
523 int ret;
524
525 ret = get_afsi_of_row(row, &afsi);
526 if (ret < 0)
527 return ret;
528 n = statistics.num;
529 x = afsi.last_played;
530 s = statistics.last_played_sum;
531 if (n > 0) {
532 q = (x > s / n)? x - s / n : s / n - x;
533 statistics.last_played_qd += q * q * n / (n + 1);
534 }
535 statistics.last_played_sum += x;
536
537 x = afsi.num_played;
538 s = statistics.num_played_sum;
539 if (n > 0) {
540 q = (x > s / n)? x - s / n : s / n - x;
541 statistics.num_played_qd += q * q * n / (n + 1);
542 }
543 statistics.num_played_sum += x;
544 statistics.num++;
545 return 1;
546 }
547
548 static int del_afs_statistics(const struct osl_row *row)
549 {
550 uint64_t n, s, q, a, new_s;
551 struct afs_info afsi;
552 int ret;
553 ret = get_afsi_of_row(row, &afsi);
554 if (ret < 0)
555 return ret;
556 n = statistics.num;
557 assert(n);
558 if (n == 1) {
559 memset(&statistics, 0, sizeof(statistics));
560 return 1;
561 }
562
563 s = statistics.last_played_sum;
564 q = statistics.last_played_qd;
565 a = afsi.last_played;
566 new_s = s - a;
567 statistics.last_played_sum = new_s;
568 statistics.last_played_qd = q + s * s / n - a * a
569 - new_s * new_s / (n - 1);
570
571 s = statistics.num_played_sum;
572 q = statistics.num_played_qd;
573 a = afsi.num_played;
574 new_s = s - a;
575 statistics.num_played_sum = new_s;
576 statistics.num_played_qd = q + s * s / n - a * a
577 - new_s * new_s / (n - 1);
578
579 statistics.num--;
580 return 1;
581 }
582
583 /*
584 * At mood open time we determine the set of admissible files for the given
585 * mood. The mood score of each admissible file is computed by adding up all
586 * mood item scores. Next, we update the afs statistics and append a struct
587 * admissible_file_info to a temporary array.
588 *
589 * When all files have been processed in this way, the final score of each
590 * admissible file is computed by adding the dynamic score (which depends on
591 * the afs_statistics and the current time) to the mood score. Finally, all
592 * audio files in the temporary array are added to the score table and the
593 * array is freed.
594 */
595 struct admissible_file_info
596 {
597 /** The admissible audio file. */
598 struct osl_row *aft_row;
599 /** Its score. */
600 long score;
601 };
602
603 /** The temporary array of admissible files. */
604 struct admissible_array {
605 /** Files are admissible wrt. this mood. */
606 struct mood *m;
607 /** The size of the array */
608 unsigned size;
609 /** Pointer to the array of admissible files. */
610 struct admissible_file_info *array;
611 };
612
613 /**
614 * Add an entry to the array of admissible files.
615 *
616 * \param aft_row The audio file to be added.
617 * \param private_data Pointer to a struct admissible_file_info.
618 *
619 * \return 1 if row admissible, 0 if not, negative on errors.
620 */
621 static int add_if_admissible(struct osl_row *aft_row, void *data)
622 {
623 struct admissible_array *aa = data;
624 int ret;
625 long score = 0;
626
627 ret = row_is_admissible(aft_row, aa->m, &score);
628 if (ret <= 0)
629 return ret;
630 if (statistics.num >= aa->size) {
631 aa->size *= 2;
632 aa->size += 100;
633 aa->array = para_realloc(aa->array,
634 aa->size * sizeof(struct admissible_file_info));
635 }
636 aa->array[statistics.num].aft_row = aft_row;
637 aa->array[statistics.num].score = score;
638 ret = add_afs_statistics(aft_row);
639 if (ret < 0)
640 return ret;
641 return 1;
642 }
643
644 /**
645 * Compute the new quadratic deviation in case one element changes.
646 *
647 * \param n Number of elements.
648 * \param old_qd The quadratic deviation before the change.
649 * \param old_val The value that was replaced.
650 * \param new_val The replacement value.
651 * \param old_sum The sum of all elements before the update.
652 *
653 * \return The new quadratic deviation resulting from replacing old_val
654 * by new_val.
655 *
656 * Given n real numbers a_1, ..., a_n, their sum S = a_1 + ... + a_n,
657 * their quadratic deviation
658 *
659 * q = (a_1 - S/n)^2 + ... + (a_n - S/n)^2,
660 *
661 * and a real number b, the quadratic deviation q' of a_1,...a_{n-1}, b (ie.
662 * the last number a_n was replaced by b) may be computed in O(1) time in terms
663 * of n, q, a_n, b, and S as
664 *
665 * q' = q + d * s - (2 * S + d) * d / n
666 * = q + d * (s - 2 * S / n - d /n),
667 *
668 * where d = b - a_n, and s = b + a_n.
669 *
670 * Example: n = 3, a_1 = 3, a_2 = 5, a_3 = 7, b = 10. Then S = 15, q = 8, d = 3,
671 * s = 17, so
672 *
673 * q + d * s - (2 * S + d) * d / n = 8 + 51 - 33 = 26,
674 *
675 * which equals q' = (3 - 6)^2 + (5 - 6)^2 + (10 - 6)^2.
676 *
677 */
678 _static_inline_ int64_t update_quadratic_deviation(int64_t n, int64_t old_qd,
679 int64_t old_val, int64_t new_val, int64_t old_sum)
680 {
681 int64_t delta = new_val - old_val;
682 int64_t sigma = new_val + old_val;
683 return old_qd + delta * (sigma - 2 * old_sum / n - delta / n);
684 }
685
686 static int update_afs_statistics(struct afs_info *old_afsi,
687 struct afs_info *new_afsi)
688 {
689 unsigned n;
690 int ret = get_num_admissible_files(&n);
691
692 if (ret < 0)
693 return ret;
694 assert(n);
695
696 statistics.last_played_qd = update_quadratic_deviation(n,
697 statistics.last_played_qd, old_afsi->last_played,
698 new_afsi->last_played, statistics.last_played_sum);
699 statistics.last_played_sum += new_afsi->last_played - old_afsi->last_played;
700
701 statistics.num_played_qd = update_quadratic_deviation(n,
702 statistics.num_played_qd, old_afsi->num_played,
703 new_afsi->num_played, statistics.num_played_sum);
704 statistics.num_played_sum += new_afsi->num_played - old_afsi->num_played;
705 return 1;
706 }
707
708 static int add_to_score_table(const struct osl_row *aft_row, long mood_score)
709 {
710 long score;
711 struct afs_info afsi;
712 int ret = get_afsi_of_row(aft_row, &afsi);
713
714 if (ret < 0)
715 return ret;
716 score = compute_score(&afsi, mood_score);
717 return score_add(aft_row, score);
718 }
719
720 static int delete_from_statistics_and_score_table(const struct osl_row *aft_row)
721 {
722 int ret = del_afs_statistics(aft_row);
723 if (ret < 0)
724 return ret;
725 return score_delete(aft_row);
726 }
727
728 /**
729 * Delete one entry from the statistics and from the score table.
730 *
731 * \param aft_row The audio file which is no longer admissible.
732 *
733 * \return Positive on success, negative on errors.
734 *
735 * \sa \ref score_delete().
736 */
737 static int mood_delete_audio_file(const struct osl_row *aft_row)
738 {
739 int ret;
740
741 ret = row_belongs_to_score_table(aft_row, NULL);
742 if (ret < 0)
743 return ret;
744 if (!ret) /* not admissible, nothing to do */
745 return 1;
746 return delete_from_statistics_and_score_table(aft_row);
747 }
748
749 /**
750 * Compute the new score of an audio file wrt. the current mood.
751 *
752 * \param aft_row Determines the audio file.
753 * \param old_afsi The audio file selector info before updating.
754 *
755 * The \a old_afsi argument may be \p NULL which indicates that no changes to
756 * the audio file info were made.
757 *
758 * \return Positive on success, negative on errors.
759 */
760 static int mood_update_audio_file(const struct osl_row *aft_row,
761 struct afs_info *old_afsi)
762 {
763 long score, percent;
764 int ret, is_admissible, was_admissible = 0;
765 struct afs_info afsi;
766 unsigned rank;
767
768 if (!current_mood)
769 return 1; /* nothing to do */
770 ret = row_belongs_to_score_table(aft_row, &rank);
771 if (ret < 0)
772 return ret;
773 was_admissible = ret;
774 ret = row_is_admissible(aft_row, current_mood, &score);
775 if (ret < 0)
776 return ret;
777 is_admissible = (ret > 0);
778 if (!was_admissible && !is_admissible)
779 return 1;
780 if (was_admissible && !is_admissible)
781 return delete_from_statistics_and_score_table(aft_row);
782 if (!was_admissible && is_admissible) {
783 ret = add_afs_statistics(aft_row);
784 if (ret < 0)
785 return ret;
786 return add_to_score_table(aft_row, score);
787 }
788 /* update score */
789 ret = get_afsi_of_row(aft_row, &afsi);
790 if (ret < 0)
791 return ret;
792 if (old_afsi) {
793 ret = update_afs_statistics(old_afsi, &afsi);
794 if (ret < 0)
795 return ret;
796 }
797 score = compute_score(&afsi, score);
798 PARA_DEBUG_LOG("score: %li\n", score);
799 percent = (score + 100) / 3;
800 if (percent > 100)
801 percent = 100;
802 else if (percent < 0)
803 percent = 0;
804 PARA_DEBUG_LOG("moving from rank %u to %li%%\n", rank, percent);
805 return score_update(aft_row, percent);
806 }
807
808 static void log_statistics(void)
809 {
810 unsigned n = statistics.num;
811 int mean_days, sigma_days;
812 /*
813 * We can not use the "now" pointer from sched.c here because we are
814 * called before schedule(), which initializes "now".
815 */
816 struct timeval rnow;
817
818 assert(current_mood);
819 PARA_NOTICE_LOG("loaded mood %s\n", current_mood->name?
820 current_mood->name : "(dummy)");
821 if (!n) {
822 PARA_WARNING_LOG("no admissible files\n");
823 return;
824 }
825 PARA_NOTICE_LOG("%u admissible files\n", statistics.num);
826 clock_get_realtime(&rnow);
827 mean_days = (rnow.tv_sec - statistics.last_played_sum / n) / 3600 / 24;
828 sigma_days = int_sqrt(statistics.last_played_qd / n) / 3600 / 24;
829 PARA_NOTICE_LOG("last_played mean/sigma: %d/%d days\n", mean_days, sigma_days);
830 PARA_NOTICE_LOG("num_played mean/sigma: %llu/%llu\n",
831 (long long unsigned)statistics.num_played_sum / n,
832 (long long unsigned)int_sqrt(statistics.num_played_qd / n));
833 }
834
835 /**
836 * Close the current mood.
837 *
838 * Frees all resources of the current mood.
839 */
840 void close_current_mood(void)
841 {
842 destroy_mood(current_mood);
843 current_mood = NULL;
844 memset(&statistics, 0, sizeof(statistics));
845 }
846
847 /**
848 * Change the current mood.
849 *
850 * \param mood_name The name of the mood to open.
851 * \param errmsg Error description is returned here.
852 *
853 * If \a mood_name is \a NULL, load the dummy mood that accepts every audio file
854 * and uses a scoring method based only on the \a last_played information.
855 *
856 * The errmsg pointer may be NULL, in which case no error message will be
857 * returned. If a non-NULL pointer is given, the caller must free *errmsg.
858 *
859 * If there is already an open mood, it will be closed first.
860 *
861 * \return Positive on success, negative on errors. Loading the dummy mood
862 * always succeeds.
863 *
864 * \sa struct \ref afs_info::last_played, \ref mp_eval_row().
865 */
866 int change_current_mood(const char *mood_name, char **errmsg)
867 {
868 int i, ret;
869 struct admissible_array aa = {
870 .size = 0,
871 .array = NULL
872 };
873
874 if (mood_name) {
875 struct mood *m;
876 struct osl_row *row;
877 struct osl_object obj = {
878 .data = (char *)mood_name,
879 .size = strlen(mood_name) + 1
880 };
881 ret = osl(osl_get_row(moods_table, BLOBCOL_NAME, &obj, &row));
882 if (ret < 0) {
883 PARA_NOTICE_LOG("no such mood: %s\n", mood_name);
884 return ret;
885 }
886 ret = load_mood(row, &m, errmsg);
887 if (ret < 0)
888 return ret;
889 close_current_mood();
890 current_mood = m;
891 } else { /* load dummy mood */
892 close_current_mood();
893 current_mood = alloc_new_mood(NULL);
894 }
895 aa.m = current_mood;
896 PARA_NOTICE_LOG("computing statistics of admissible files\n");
897 ret = audio_file_loop(&aa, add_if_admissible);
898 if (ret < 0)
899 return ret;
900 for (i = 0; i < statistics.num; i++) {
901 struct admissible_file_info *a = aa.array + i;
902 ret = add_to_score_table(a->aft_row, a->score);
903 if (ret < 0)
904 goto out;
905 }
906 log_statistics();
907 ret = statistics.num;
908 out:
909 free(aa.array);
910 return ret;
911 }
912
913 /*
914 * Close and re-open the current mood.
915 *
916 * This function is called on events which render the current list of
917 * admissible files useless, for example if an attribute is removed from the
918 * attribute table.
919 *
920 * If no mood is currently open, the function returns success.
921 */
922 static int reload_current_mood(void)
923 {
924 int ret;
925 char *mood_name = NULL;
926
927 ret = clear_score_table();
928 if (ret < 0)
929 return ret;
930 if (!current_mood)
931 return 1;
932 PARA_NOTICE_LOG("reloading %s\n", current_mood->name?
933 current_mood->name : "(dummy)");
934 if (current_mood->name)
935 mood_name = para_strdup(current_mood->name);
936 close_current_mood();
937 ret = change_current_mood(mood_name, NULL);
938 free(mood_name);
939 return ret;
940 }
941
942 /**
943 * Notification callback for the moods table.
944 *
945 * \param event Type of the event just occurred.
946 * \param pb Unused.
947 * \param data Its type depends on the event.
948 *
949 * This function performs actions required due to the occurrence of the given
950 * event. Possible actions include reload of the current mood and update of the
951 * score of an audio file.
952 *
953 * \return Standard.
954 */
955 int moods_event_handler(enum afs_events event, __a_unused struct para_buffer *pb,
956 void *data)
957 {
958 if (!current_mood)
959 return 0;
960 switch (event) {
961 /*
962 * The three blob events might change the set of admissible files,
963 * so we must reload the score list.
964 */
965 case BLOB_RENAME:
966 case BLOB_REMOVE:
967 case BLOB_ADD:
968 if (data == moods_table || data == playlists_table)
969 return 1; /* no reload necessary for these */
970 return reload_current_mood();
971 /* these also require reload of the score table */
972 case ATTRIBUTE_ADD:
973 case ATTRIBUTE_REMOVE:
974 case ATTRIBUTE_RENAME:
975 return reload_current_mood();
976 /* changes to the aft only require to re-examine the audio file */
977 case AFSI_CHANGE: {
978 struct afsi_change_event_data *aced = data;
979 return mood_update_audio_file(aced->aft_row, aced->old_afsi);
980 }
981 case AFHI_CHANGE:
982 case AUDIO_FILE_RENAME:
983 case AUDIO_FILE_ADD:
984 return mood_update_audio_file(data, NULL);
985 case AUDIO_FILE_REMOVE:
986 return mood_delete_audio_file(data);
987 default:
988 return 1;
989 }
990 }