Merge branch 't/ssh_keys'
[paraslash.git] / mood.c
1 /*
2 * Copyright (C) 2007-2011 Andre Noll <maan@systemlinux.org>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7 /** \file mood.c Paraslash's mood handling functions. */
8
9 #include <regex.h>
10 #include <osl.h>
11
12 #include "para.h"
13 #include "error.h"
14 #include "string.h"
15 #include "afh.h"
16 #include "afs.h"
17 #include "list.h"
18 #include "ipc.h"
19 #include "mm.h"
20
21 /**
22 * Contains statistical data of the currently admissible audio files.
23 *
24 * It is used to assign normalized score values to each admissible audio file.
25 */
26 struct afs_statistics {
27 /** Sum of num played over all admissible files. */
28 int64_t num_played_sum;
29 /** Sum of last played times over all admissible files. */
30 int64_t last_played_sum;
31 /** Quadratic deviation of num played time. */
32 int64_t num_played_qd;
33 /** Quadratic deviation of last played time. */
34 int64_t last_played_qd;
35 /** Number of admissible files */
36 unsigned num;
37 };
38 static struct afs_statistics statistics;
39
40 /**
41 * Each line of the current mood corresponds to a mood_item.
42 */
43 struct mood_item {
44 /** The method this line is referring to. */
45 const struct mood_method *method;
46 /** The data structure computed by the mood parser. */
47 void *parser_data;
48 /** The given score value, or zero if none was given. */
49 int32_t score_arg;
50 /** Non-zero if random scoring was requested. */
51 int random_score;
52 /** Whether the "not" keyword was given in the mood line. */
53 int logical_not;
54 /** The position in the list of items. */
55 struct list_head mood_item_node;
56 };
57
58 /**
59 * Created from the mood definition by mood_open().
60 *
61 * When a mood is opened, each line of its definition is investigated, and a
62 * corresponding mood item is produced. Each mood line starts with \p accept,
63 * \p deny, or \p score which determines the type of the mood line. For each
64 * such type a linked list is maintained whose entries are the mood items.
65 *
66 * \sa mood_item, mood_open().
67 */
68 struct mood {
69 /** The name of this mood. */
70 char *name;
71 /** The list of mood items of type \p accept. */
72 struct list_head accept_list;
73 /** The list of mood items of type \p deny. */
74 struct list_head deny_list;
75 /** The list of mood items of type \p score. */
76 struct list_head score_list;
77 };
78
79 static struct mood *current_mood;
80
81 /**
82 * Rough approximation to sqrt.
83 *
84 * \param x Integer of which to calculate the sqrt.
85 *
86 * \return An integer res with res * res <= x.
87 */
88 __a_const static uint64_t int_sqrt(uint64_t x)
89 {
90 uint64_t op, res, one = 1;
91 op = x;
92 res = 0;
93
94 one = one << 62;
95 while (one > op)
96 one >>= 2;
97
98 while (one != 0) {
99 if (op >= res + one) {
100 op = op - (res + one);
101 res = res + 2 * one;
102 }
103 res /= 2;
104 one /= 4;
105 }
106 // PARA_NOTICE_LOG("sqrt(%llu) = %llu\n", x, res);
107 return res;
108 }
109
110 /* returns 1 if row matches score item, 0 if not. */
111 static int get_item_score(struct mood_item *item, const struct afs_info *afsi,
112 const struct afh_info *afhi, const char *path, long *score,
113 long *score_arg_sum)
114 {
115 int ret, match = 1;
116
117 *score_arg_sum += item->random_score? 100 : PARA_ABS(item->score_arg);
118 ret = 100;
119 if (item->method) {
120 ret = item->method->score_function(path, afsi, afhi,
121 item->parser_data);
122 if ((ret < 0 && !item->logical_not) || (ret >= 0 && item->logical_not))
123 match = 0; /* no match */
124 }
125 if (item->random_score)
126 *score = PARA_ABS(ret) * para_random(100);
127 else
128 *score = PARA_ABS(ret) * item->score_arg;
129 return match;
130 }
131
132 /* returns 1 if row admissible, 0 if not, negative on errors */
133 static int compute_mood_score(const struct osl_row *aft_row, struct mood *m,
134 long *result)
135 {
136 struct mood_item *item;
137 int ret, match = 0;
138 long score_arg_sum = 0, score = 0, item_score;
139 struct afs_info afsi;
140 struct afh_info afhi;
141 char *path;
142
143 if (!m)
144 return -E_NO_MOOD;
145 ret = get_afsi_of_row(aft_row, &afsi);
146 if (ret< 0)
147 return ret;
148 ret = get_afhi_of_row(aft_row, &afhi);
149 if (ret< 0)
150 return ret;
151 ret = get_audio_file_path_of_row(aft_row, &path);
152 if (ret< 0)
153 return ret;
154 /* reject audio file if it matches any entry in the deny list */
155 list_for_each_entry(item, &m->deny_list, mood_item_node) {
156 ret = get_item_score(item, &afsi, &afhi, path, &item_score,
157 &score_arg_sum);
158 if (ret > 0) /* not admissible */
159 return 0;
160 score += item_score;
161 }
162 list_for_each_entry(item, &m->accept_list, mood_item_node) {
163 ret = get_item_score(item, &afsi, &afhi, path, &item_score,
164 &score_arg_sum);
165 if (ret == 0)
166 continue;
167 match = 1;
168 score += item_score;
169 }
170 /* reject if there is no matching entry in the accept list */
171 if (!match && !list_empty(&m->accept_list))
172 return 0;
173 list_for_each_entry(item, &m->score_list, mood_item_node) {
174 ret = get_item_score(item, &afsi, &afhi, path, &item_score,
175 &score_arg_sum);
176 score += item_score;
177 }
178 if (score_arg_sum)
179 score /= score_arg_sum;
180 *result = score;
181 return 1;
182 }
183
184 static void cleanup_list_entry(struct mood_item *item)
185 {
186 if (item->method && item->method->cleanup)
187 item->method->cleanup(item->parser_data);
188 else
189 free(item->parser_data);
190 list_del(&item->mood_item_node);
191 free(item);
192 }
193
194 static void destroy_mood(struct mood *m)
195 {
196 struct mood_item *tmp, *item;
197
198 if (!m)
199 return;
200 list_for_each_entry_safe(item, tmp, &m->accept_list, mood_item_node)
201 cleanup_list_entry(item);
202 list_for_each_entry_safe(item, tmp, &m->deny_list, mood_item_node)
203 cleanup_list_entry(item);
204 list_for_each_entry_safe(item, tmp, &m->score_list, mood_item_node)
205 cleanup_list_entry(item);
206 free(m->name);
207 free(m);
208 }
209
210 static struct mood *alloc_new_mood(const char *name)
211 {
212 struct mood *m = para_calloc(sizeof(struct mood));
213 m->name = para_strdup(name);
214 INIT_LIST_HEAD(&m->accept_list);
215 INIT_LIST_HEAD(&m->deny_list);
216 INIT_LIST_HEAD(&m->score_list);
217 return m;
218 }
219
220 /** The different types of a mood line. */
221 enum mood_line_type {
222 /** Invalid. */
223 ML_INVALID,
224 /** Accept line. */
225 ML_ACCEPT,
226 /** Deny line. */
227 ML_DENY,
228 /** Score line. */
229 ML_SCORE
230 };
231
232 /** Data passed to the parser of a mood line. */
233 struct mood_line_parser_data {
234 /** The mood this mood line belongs to. */
235 struct mood *m;
236 /** The line number in the mood definition. */
237 unsigned line_num;
238 };
239
240 /*
241 * <accept [with score <score>] | deny [with score <score>] | score <score>>
242 * [if] [not] <mood_method> [options]
243 * <score> is either an integer or "random" which assigns a random score to
244 * all matching files
245 */
246
247 static int parse_mood_line(char *mood_line, void *data)
248 {
249 struct mood_line_parser_data *mlpd = data;
250 char **argv;
251 unsigned num_words;
252 char **w;
253 int i, ret;
254 enum mood_line_type mlt = ML_INVALID;
255 struct mood_item *mi = NULL;
256
257 mlpd->line_num++;
258 ret = create_argv(mood_line, " \t", &argv);
259 if (ret < 0)
260 return ret;
261 num_words = ret;
262 if (!num_words) /* empty line */
263 goto out;
264 w = argv;
265 if (**w == '#') /* comment */
266 goto out;
267 if (!strcmp(*w, "accept"))
268 mlt = ML_ACCEPT;
269 else if (!strcmp(*w, "deny"))
270 mlt = ML_DENY;
271 else if (!strcmp(*w, "score"))
272 mlt = ML_SCORE;
273 ret = -E_MOOD_SYNTAX;
274 if (mlt == ML_INVALID)
275 goto out;
276 mi = para_calloc(sizeof(struct mood_item));
277 if (mlt != ML_SCORE) {
278 ret = -E_MOOD_SYNTAX;
279 w++;
280 if (!*w)
281 goto out;
282 if (strcmp(*w, "with"))
283 goto check_for_if;
284 w++;
285 if (!*w)
286 goto out;
287 if (strcmp(*w, "score"))
288 goto out;
289 }
290 if (mlt == ML_SCORE || !strcmp(*w, "score")) {
291 ret = -E_MOOD_SYNTAX;
292 w++;
293 if (!*w)
294 goto out;
295 if (strcmp(*w, "random")) {
296 mi->random_score = 0;
297 ret = para_atoi32(*w, &mi->score_arg);
298 if (ret < 0)
299 goto out;
300 } else {
301 mi->random_score = 1;
302 if (!*(w + 1))
303 goto success; /* the line "score random" is valid */
304 }
305 } else
306 mi->score_arg = 0;
307 ret = -E_MOOD_SYNTAX;
308 w++;
309 if (!*w)
310 goto out;
311 check_for_if:
312 if (!strcmp(*w, "if")) {
313 ret = -E_MOOD_SYNTAX;
314 w++;
315 if (!*w)
316 goto out;
317 }
318 if (!strcmp(*w, "not")) {
319 ret = -E_MOOD_SYNTAX;
320 w++;
321 if (!*w)
322 goto out;
323 mi->logical_not = 1;
324 } else
325 mi->logical_not = 0;
326 for (i = 0; mood_methods[i].parser; i++) {
327 if (strcmp(*w, mood_methods[i].name))
328 continue;
329 break;
330 }
331 ret = -E_MOOD_SYNTAX;
332 if (!mood_methods[i].parser)
333 goto out;
334 ret = mood_methods[i].parser(num_words - 1 - (w - argv), w,
335 &mi->parser_data);
336 if (ret < 0)
337 goto out;
338 mi->method = &mood_methods[i];
339 success:
340 if (mlpd->m) {
341 if (mlt == ML_ACCEPT)
342 para_list_add(&mi->mood_item_node, &mlpd->m->accept_list);
343 else if (mlt == ML_DENY)
344 para_list_add(&mi->mood_item_node, &mlpd->m->deny_list);
345 else
346 para_list_add(&mi->mood_item_node, &mlpd->m->score_list);
347 }
348 PARA_DEBUG_LOG("%s entry added, method: %p\n", mlt == ML_ACCEPT? "accept" :
349 (mlt == ML_DENY? "deny" : "score"), mi->method);
350 ret = 1;
351 out:
352 free_argv(argv);
353 if (ret >= 0)
354 return ret;
355 if (mi) {
356 free(mi->parser_data);
357 free(mi);
358 }
359 return ret;
360 }
361
362 static int load_mood(const struct osl_row *mood_row, struct mood **m)
363 {
364 char *mood_name;
365 struct osl_object mood_def;
366 struct mood_line_parser_data mlpd = {.line_num = 0};
367 int ret = mood_get_name_and_def_by_row(mood_row, &mood_name, &mood_def);
368
369 if (ret < 0)
370 return ret;
371 if (!*mood_name)
372 return -E_DUMMY_ROW;
373 mlpd.m = alloc_new_mood(mood_name);
374 ret = for_each_line_ro(mood_def.data, mood_def.size,
375 parse_mood_line, &mlpd);
376 osl_close_disk_object(&mood_def);
377 if (ret < 0) {
378 PARA_ERROR_LOG("unable to load mood %s: %s\n", mlpd.m->name,
379 para_strerror(-ret));
380 destroy_mood(mlpd.m);
381 return ret;
382 }
383 *m = mlpd.m;
384 return 1;
385 }
386
387 static int check_mood(struct osl_row *mood_row, void *data)
388 {
389 struct para_buffer *pb = data;
390 char *mood_name;
391 struct osl_object mood_def;
392 struct mood_line_parser_data mlpd = {.line_num = 0};
393
394 int ret = mood_get_name_and_def_by_row(mood_row, &mood_name, &mood_def);
395
396 if (ret < 0) {
397 para_printf(pb, "failed to get mood definition: %s\n",
398 para_strerror(-ret));
399 return ret;
400 }
401 if (!*mood_name) /* ignore dummy row */
402 goto out;
403 ret = para_printf(pb, "checking mood %s...\n", mood_name);
404 if (ret < 0)
405 goto out;
406 ret = for_each_line_ro(mood_def.data, mood_def.size,
407 parse_mood_line, &mlpd);
408 if (ret < 0)
409 para_printf(pb, "%s line %u: %s\n", mood_name, mlpd.line_num,
410 para_strerror(-ret));
411 out:
412 osl_close_disk_object(&mood_def);
413 return ret;
414 }
415
416 /**
417 * Check all moods for syntax errors.
418 *
419 * \param fd The afs socket.
420 * \param query Unused.
421 */
422 void mood_check_callback(int fd, __a_unused const struct osl_object *query)
423 {
424 struct para_buffer pb = {
425 .max_size = SHMMAX,
426 .private_data = &fd,
427 .max_size_handler = pass_buffer_as_shm
428 };
429
430 int ret = para_printf(&pb, "checking moods...\n");
431 if (ret < 0)
432 return;
433 osl_rbtree_loop(moods_table, BLOBCOL_ID, &pb,
434 check_mood);
435 if (pb.offset)
436 pass_buffer_as_shm(pb.buf, pb.offset, &fd);
437 free(pb.buf);
438 }
439
440 #if 0
441 static unsigned int_log2(uint64_t x)
442 {
443 unsigned res = 0;
444
445 while (x) {
446 x /= 2;
447 res++;
448 }
449 return res;
450 }
451 #endif
452
453 static int64_t normalized_value(int64_t x, int64_t n, int64_t sum, int64_t qd)
454 {
455 if (!n || !qd)
456 return 0;
457 return 100 * (n * x - sum) / (int64_t)int_sqrt(n * qd);
458 }
459
460 static long compute_num_played_score(struct afs_info *afsi)
461 {
462 return -normalized_value(afsi->num_played, statistics.num,
463 statistics.num_played_sum, statistics.num_played_qd);
464 }
465
466 static long compute_last_played_score(struct afs_info *afsi)
467 {
468 return -normalized_value(afsi->last_played, statistics.num,
469 statistics.last_played_sum, statistics.last_played_qd);
470 }
471
472 static long compute_dynamic_score(const struct osl_row *aft_row)
473 {
474 struct afs_info afsi;
475 int64_t score, nscore = 0, lscore = 0;
476 int ret;
477
478 ret = get_afsi_of_row(aft_row, &afsi);
479 if (ret < 0)
480 return -100;
481 nscore = compute_num_played_score(&afsi);
482 lscore = compute_last_played_score(&afsi);
483 score = nscore + lscore;
484 return score;
485 }
486
487 static int add_afs_statistics(const struct osl_row *row)
488 {
489 uint64_t n, x, s;
490 struct afs_info afsi;
491 int ret;
492
493 ret = get_afsi_of_row(row, &afsi);
494 if (ret < 0)
495 return ret;
496 n = statistics.num;
497 x = afsi.last_played;
498 s = statistics.last_played_sum;
499 if (n > 0)
500 statistics.last_played_qd += (x - s / n) * (x - s / n) * n / (n + 1);
501 statistics.last_played_sum += x;
502
503 x = afsi.num_played;
504 s = statistics.num_played_sum;
505 if (n > 0)
506 statistics.num_played_qd += (x - s / n) * (x - s / n) * n / (n + 1);
507 statistics.num_played_sum += x;
508 statistics.num++;
509 return 1;
510 }
511
512 static int del_afs_statistics(const struct osl_row *row)
513 {
514 uint64_t n, s, q, a, new_s;
515 struct afs_info afsi;
516 int ret;
517 ret = get_afsi_of_row(row, &afsi);
518 if (ret < 0)
519 return ret;
520 n = statistics.num;
521 assert(n);
522 if (n == 1) {
523 memset(&statistics, 0, sizeof(statistics));
524 return 1;
525 }
526
527 s = statistics.last_played_sum;
528 q = statistics.last_played_qd;
529 a = afsi.last_played;
530 new_s = s - a;
531 statistics.last_played_sum = new_s;
532 statistics.last_played_qd = q + s * s / n - a * a
533 - new_s * new_s / (n - 1);
534
535 s = statistics.num_played_sum;
536 q = statistics.num_played_qd;
537 a = afsi.num_played;
538 new_s = s - a;
539 statistics.num_played_sum = new_s;
540 statistics.num_played_qd = q + s * s / n - a * a
541 - new_s * new_s / (n - 1);
542
543 statistics.num--;
544 return 1;
545 }
546
547 /**
548 * Structure used during mood_open().
549 *
550 * At mood open time, we look at each file in the audio file table in order to
551 * determine whether it is admissible. If a file happens to be admissible, its
552 * mood score is computed by calling each relevant mood_score_function. Next,
553 * we update the afs_statistics and add a struct admissible_file_info to a
554 * temporary array.
555 *
556 * If all files have been processed that way, the final score of each
557 * admissible file is computed by adding the dynamic score (which depends on
558 * the afs_statistics) to the mood score. Finally, all audio files in the
559 * array are added to the score table and the admissible array is freed.
560 *
561 * \sa mood_method, admissible_array.
562 */
563 struct admissible_file_info
564 {
565 /** The admissible audio file. */
566 struct osl_row *aft_row;
567 /** Its score. */
568 long score;
569 };
570
571 /** The temporary array of admissible files. */
572 struct admissible_array {
573 /** Files are admissible wrt. this mood. */
574 struct mood *m;
575 /** The size of the array */
576 unsigned size;
577 /** Pointer to the array of admissible files. */
578 struct admissible_file_info *array;
579 };
580
581 /**
582 * Add an entry to the array of admissible files.
583 *
584 * \param aft_row The audio file to be added.
585 * \param private_data Pointer to a struct admissible_file_info.
586 *
587 * \return 1 if row admissible, 0 if not, negative on errors.
588 */
589 static int add_if_admissible(struct osl_row *aft_row, void *data)
590 {
591 struct admissible_array *aa = data;
592 int ret;
593 long score = 0;
594
595 ret = compute_mood_score(aft_row, aa->m, &score);
596 if (ret <= 0)
597 return ret;
598 if (statistics.num >= aa->size) {
599 aa->size *= 2;
600 aa->size += 100;
601 aa->array = para_realloc(aa->array,
602 aa->size * sizeof(struct admissible_file_info));
603 }
604 aa->array[statistics.num].aft_row = aft_row;
605 aa->array[statistics.num].score = score;
606 ret = add_afs_statistics(aft_row);
607 if (ret < 0)
608 return ret;
609 return 1;
610 }
611
612 /**
613 * Compute the new quadratic deviation in case one element changes.
614 *
615 * \param n Number of elements.
616 * \param old_qd The quadratic deviation before the change.
617 * \param old_val The value that was replaced.
618 * \param new_val The replacement value.
619 * \param old_sum The sum of all elements before the update.
620 *
621 * \return The new quadratic deviation resulting from replacing old_val
622 * by new_val.
623 *
624 * Given n real numbers a_1, ..., a_n, their sum S = a_1 + ... + a_n,
625 * their quadratic deviation
626 *
627 * q = (a_1 - S/n)^2 + ... + (a_n - S/n)^2,
628 *
629 * and a real number b, the quadratic deviation q' of a_1,...a_{n-1}, b (ie.
630 * the last number a_n was replaced by b) may be computed in O(1) time in terms
631 * of n, q, a_n, b, and S as
632 *
633 * q' = q + d * s - (2 * S + d) * d / n,
634 *
635 * where d = b - a_n, and s = b + a_n.
636 *
637 * Example: n = 3, a_1 = 3, a_2 = 5, a_3 = 7, b = 10. Then S = 15, q = 8, d = 3,
638 * s = 17, so
639 *
640 * q + d * s - (2 * S + d) * d / n = 8 + 51 - 33 = 26,
641 *
642 * which equals q' = (3 - 6)^2 + (5 - 6)^2 + (10 - 6)^2.
643 *
644 */
645 _static_inline_ int64_t update_quadratic_deviation(int64_t n, int64_t old_qd,
646 int64_t old_val, int64_t new_val, int64_t old_sum)
647 {
648 int64_t delta = new_val - old_val;
649 int64_t sigma = new_val + old_val;
650 return old_qd + delta * sigma - (2 * old_sum + delta) * delta / n;
651 }
652
653 static int update_afs_statistics(struct afs_info *old_afsi, struct afs_info *new_afsi)
654 {
655 unsigned n;
656 int ret = get_num_admissible_files(&n);
657
658 if (ret < 0)
659 return ret;
660 assert(n);
661
662 statistics.last_played_qd = update_quadratic_deviation(n,
663 statistics.last_played_qd, old_afsi->last_played,
664 new_afsi->last_played, statistics.last_played_sum);
665 statistics.last_played_sum += new_afsi->last_played - old_afsi->last_played;
666
667 statistics.num_played_qd = update_quadratic_deviation(n,
668 statistics.num_played_qd, old_afsi->num_played,
669 new_afsi->num_played, statistics.num_played_sum);
670 statistics.num_played_sum += new_afsi->num_played - old_afsi->num_played;
671 return 1;
672 }
673
674 static int add_to_score_table(const struct osl_row *aft_row, long mood_score)
675 {
676 long score = (compute_dynamic_score(aft_row) + mood_score) / 3;
677 return score_add(aft_row, score);
678 }
679
680 static int delete_from_statistics_and_score_table(const struct osl_row *aft_row)
681 {
682 int ret = del_afs_statistics(aft_row);
683 if (ret < 0)
684 return ret;
685 return score_delete(aft_row);
686 }
687
688 /**
689 * Delete one entry from the statistics and from the score table.
690 *
691 * \param aft_row The audio file which is no longer admissible.
692 *
693 * \return Positive on success, negative on errors.
694 *
695 * \sa score_delete().
696 */
697 static int mood_delete_audio_file(const struct osl_row *aft_row)
698 {
699 int ret;
700
701 ret = row_belongs_to_score_table(aft_row, NULL);
702 if (ret < 0)
703 return ret;
704 if (!ret) /* not admissible, nothing to do */
705 return 1;
706 return delete_from_statistics_and_score_table(aft_row);
707 }
708
709 /**
710 * Compute the new score of an audio file wrt. the current mood.
711 *
712 * \param aft_row Determines the audio file.
713 * \param old_afsi The audio file selector info before updating.
714 *
715 * The \a old_afsi argument may be \p NULL which indicates that no changes to
716 * the audio file info were made.
717 *
718 * \return Positive on success, negative on errors.
719 */
720 static int mood_update_audio_file(const struct osl_row *aft_row,
721 struct afs_info *old_afsi)
722 {
723 long score, percent;
724 int ret, is_admissible, was_admissible = 0;
725 struct afs_info afsi;
726 unsigned rank;
727
728 if (!current_mood)
729 return 1; /* nothing to do */
730 ret = row_belongs_to_score_table(aft_row, &rank);
731 if (ret < 0)
732 return ret;
733 was_admissible = ret;
734 ret = compute_mood_score(aft_row, current_mood, &score);
735 if (ret < 0)
736 return ret;
737 is_admissible = (ret > 0);
738 if (!was_admissible && !is_admissible)
739 return 1;
740 if (was_admissible && !is_admissible)
741 return delete_from_statistics_and_score_table(aft_row);
742 if (!was_admissible && is_admissible) {
743 ret = add_afs_statistics(aft_row);
744 if (ret < 0)
745 return ret;
746 return add_to_score_table(aft_row, score);
747 }
748 /* update score */
749 ret = get_afsi_of_row(aft_row, &afsi);
750 if (ret < 0)
751 return ret;
752 if (old_afsi) {
753 ret = update_afs_statistics(old_afsi, &afsi);
754 if (ret < 0)
755 return ret;
756 }
757 score += compute_num_played_score(&afsi);
758 score += compute_last_played_score(&afsi);
759 score /= 3;
760 PARA_DEBUG_LOG("score: %li\n", score);
761 percent = (score + 100) / 3;
762 if (percent > 100)
763 percent = 100;
764 else if (percent < 0)
765 percent = 0;
766 PARA_DEBUG_LOG("moving from rank %u to %lu%%\n", rank, percent);
767 return score_update(aft_row, percent);
768 }
769
770 static void log_statistics(void)
771 {
772 unsigned n = statistics.num;
773
774 if (!n) {
775 PARA_NOTICE_LOG("no admissible files\n");
776 return;
777 }
778 PARA_INFO_LOG("last_played mean: %lli, last_played sigma: %llu\n",
779 (long long int)(statistics.last_played_sum / n),
780 (long long unsigned)int_sqrt(statistics.last_played_qd / n));
781 PARA_INFO_LOG("num_played mean: %lli, num_played sigma: %llu\n",
782 (long long int)statistics.num_played_sum / n,
783 (long long unsigned)int_sqrt(statistics.num_played_qd / n));
784 }
785
786 /**
787 * Close the current mood.
788 *
789 * Free all resources of the current mood which were allocated during
790 * mood_open().
791 */
792 void close_current_mood(void)
793 {
794 destroy_mood(current_mood);
795 current_mood = NULL;
796 memset(&statistics, 0, sizeof(statistics));
797 }
798
799 /**
800 * Change the current mood.
801 *
802 * \param mood_name The name of the mood to open.
803 *
804 * If \a mood_name is \a NULL, load the dummy mood that accepts every audio file
805 * and uses a scoring method based only on the \a last_played information.
806 *
807 * If there is already an open mood, it will be closed first.
808 *
809 * \return Positive on success, negative on errors. Loading the dummy mood
810 * always succeeds.
811 *
812 * \sa struct admissible_file_info, struct admissible_array, struct
813 * afs_info::last_played, mood_close().
814 */
815 int change_current_mood(char *mood_name)
816 {
817 int i, ret;
818 struct admissible_array aa = {
819 .size = 0,
820 .array = NULL
821 };
822
823 if (mood_name) {
824 struct mood *m;
825 struct osl_row *row;
826 struct osl_object obj = {
827 .data = mood_name,
828 .size = strlen(mood_name) + 1
829 };
830 ret = osl(osl_get_row(moods_table, BLOBCOL_NAME, &obj, &row));
831 if (ret < 0) {
832 PARA_NOTICE_LOG("no such mood: %s\n", mood_name);
833 return ret;
834 }
835 ret = load_mood(row, &m);
836 if (ret < 0)
837 return ret;
838 close_current_mood();
839 current_mood = m;
840 } else {
841 close_current_mood();
842 current_mood = alloc_new_mood("dummy");
843 }
844 aa.m = current_mood;
845 PARA_NOTICE_LOG("computing statistics of admissible files\n");
846 ret = audio_file_loop(&aa, add_if_admissible);
847 if (ret < 0)
848 return ret;
849 log_statistics();
850 PARA_INFO_LOG("%d admissible files \n", statistics.num);
851 for (i = 0; i < statistics.num; i++) {
852 struct admissible_file_info *a = aa.array + i;
853 ret = add_to_score_table(a->aft_row, a->score);
854 if (ret < 0)
855 goto out;
856 }
857 PARA_NOTICE_LOG("loaded mood %s\n", current_mood->name);
858 ret = statistics.num;
859 out:
860 free(aa.array);
861 return ret;
862 }
863 /**
864 * Close and re-open the current mood.
865 *
866 * This function is used if changes to the audio file table or the
867 * attribute table were made that render the current list of admissible
868 * files useless. For example, if an attribute is removed from the
869 * attribute table, this function is called.
870 *
871 * \return Positive on success, negative on errors. If no mood is currently
872 * open, the function returns success.
873 *
874 * \sa mood_open(), mood_close().
875 */
876 static int reload_current_mood(void)
877 {
878 int ret;
879 char *mood_name = NULL;
880
881 if (!current_mood)
882 return 1;
883 PARA_NOTICE_LOG("reloading %s\n", current_mood->name?
884 current_mood->name : "(dummy)");
885 if (current_mood->name)
886 mood_name = para_strdup(current_mood->name);
887 close_current_mood();
888 ret = change_current_mood(mood_name);
889 free(mood_name);
890 return ret;
891 }
892
893 /**
894 * Notification callback for the moods table.
895 *
896 * \param event Type of the event just occurred.
897 * \param pb Unused.
898 * \param data Its type depends on the event.
899 *
900 * This function performs actions required due to the occurrence of the given
901 * event. Possible actions include reload of the current mood and update of the
902 * score of an audio file.
903 */
904 int moods_event_handler(enum afs_events event, __a_unused struct para_buffer *pb,
905 void *data)
906 {
907 if (!current_mood)
908 return 0;
909 switch (event) {
910 /*
911 * The three blob events might change the set of admissible files,
912 * so we must reload the score list.
913 */
914 case BLOB_RENAME:
915 case BLOB_REMOVE:
916 case BLOB_ADD:
917 if (data == moods_table || data == playlists_table)
918 return 1; /* no reload necessary for these */
919 return reload_current_mood();
920 /* these also require reload of the score table */
921 case ATTRIBUTE_ADD:
922 case ATTRIBUTE_REMOVE:
923 case ATTRIBUTE_RENAME:
924 return reload_current_mood();
925 /* changes to the aft only require to re-examine the audio file */
926 case AFSI_CHANGE: {
927 struct afsi_change_event_data *aced = data;
928 return mood_update_audio_file(aced->aft_row, aced->old_afsi);
929 }
930 case AFHI_CHANGE:
931 case AUDIO_FILE_RENAME:
932 case AUDIO_FILE_ADD:
933 return mood_update_audio_file(data, NULL);
934 case AUDIO_FILE_REMOVE:
935 return mood_delete_audio_file(data);
936 default:
937 return 1;
938 }
939 }