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