1 /* Copyright (C) 2007 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
3 /** \file mood.c Paraslash's mood handling functions. */
18 * Mood parser API. It's overkill to have an own header file for
19 * these declarations as they are only needed in this .c file.
22 int mp_init(const char *definition, int nbytes, struct mp_context **result,
24 bool mp_eval_row(const struct osl_row *aft_row, struct mp_context *ctx);
25 void mp_shutdown(struct mp_context *ctx);
28 * Contains statistical data of the currently admissible audio files.
30 * It is used to assign normalized score values to each admissible audio file.
32 struct afs_statistics {
33 /** Sum of num played over all admissible files. */
34 int64_t num_played_sum;
35 /** Sum of last played times over all admissible files. */
36 int64_t last_played_sum;
37 /** Quadratic deviation of num played count. */
38 int64_t num_played_qd;
39 /** Quadratic deviation of last played time. */
40 int64_t last_played_qd;
41 /** Number of admissible files */
44 static struct afs_statistics statistics;
47 /** The name of this mood. */
49 /** Info for the bison parser. */
50 struct mp_context *parser_context;
54 * If current_mood is NULL then no mood is currently open. If
55 * current_mood->name is NULL, the dummy mood is currently open.
57 static struct mood *current_mood;
60 * Find the position of the most-significant set bit.
62 * Copied and slightly adapted from the linux source tree, version 4.9.39
65 __a_const static uint32_t fls64(uint64_t v)
68 const uint64_t ones = ~(uint64_t)0U;
70 if ((v & (ones << 32)) == 0) {
74 if ((v & (ones << (64 - 16))) == 0) {
78 if ((v & (ones << (64 - 8))) == 0) {
82 if ((v & (ones << (64 - 4))) == 0) {
86 if ((v & (ones << (64 - 2))) == 0) {
90 if ((v & (ones << (64 - 1))) == 0)
96 * Compute the integer square root floor(sqrt(x)).
98 * Taken 2007 from the linux source tree.
100 __a_const static uint64_t int_sqrt(uint64_t x)
102 uint64_t op = x, res = 0, one = 1;
104 one = one << (fls64(x) & ~one);
106 if (op >= res + one) {
107 op = op - (res + one);
116 /* returns 1 if row admissible, 0 if not, negative on errors */
117 static int row_is_admissible(const struct osl_row *aft_row, struct mood *m)
121 return mp_eval_row(aft_row, m->parser_context);
124 static void destroy_mood(struct mood *m)
128 mp_shutdown(m->parser_context);
133 static struct mood *alloc_new_mood(const char *name)
135 struct mood *m = para_calloc(sizeof(struct mood));
137 m->name = para_strdup(name);
141 static int load_mood(const struct osl_row *mood_row, struct mood **m,
145 struct osl_object mood_def;
148 ret = mood_get_name_and_def_by_row(mood_row, &mood_name, &mood_def);
151 *errmsg = make_message(
152 "could not read mood definition");
156 *m = alloc_new_mood(mood_name);
157 PARA_INFO_LOG("opening mood %s\n", mood_name);
158 ret = mp_init(mood_def.data, mood_def.size, &(*m)->parser_context, errmsg);
159 osl_close_disk_object(&mood_def);
163 static int check_mood(struct osl_row *mood_row, void *data)
165 struct para_buffer *pb = data;
166 char *mood_name, *errmsg;
167 struct osl_object mood_def;
169 int ret = mood_get_name_and_def_by_row(mood_row, &mood_name, &mood_def);
172 para_printf(pb, "cannot read mood\n");
175 if (!*mood_name) /* ignore dummy row */
177 m = alloc_new_mood("check");
178 ret = mp_init(mood_def.data, mood_def.size, &m->parser_context,
181 para_printf(pb, "%s: %s\n", mood_name, errmsg);
183 para_printf(pb, "%s\n", para_strerror(-ret));
186 ret = 1; /* don't fail the loop on invalid mood definitions */
188 osl_close_disk_object(&mood_def);
193 * Check all moods for syntax errors.
195 * \param aca Only ->pbout is used for diagnostics.
197 * \return Negative on fatal errors. Inconsistent mood definitions are not
198 * considered an error.
200 int mood_check_callback(struct afs_callback_arg *aca)
202 para_printf(&aca->pbout, "checking moods...\n");
203 return osl(osl_rbtree_loop(moods_table, BLOBCOL_ID, &aca->pbout,
207 static int64_t normalized_value(int64_t x, int64_t n, int64_t sum, int64_t qd)
211 return 100 * (n * x - sum) / (int64_t)int_sqrt(n) / (int64_t)int_sqrt(qd);
214 static long compute_score(struct afs_info *afsi)
216 long score = -normalized_value(afsi->num_played, statistics.num,
217 statistics.num_played_sum, statistics.num_played_qd);
218 score -= normalized_value(afsi->last_played, statistics.num,
219 statistics.last_played_sum, statistics.last_played_qd);
223 static int add_afs_statistics(const struct osl_row *row)
226 struct afs_info afsi;
229 ret = get_afsi_of_row(row, &afsi);
233 x = afsi.last_played;
234 s = statistics.last_played_sum;
236 q = (x > s / n)? x - s / n : s / n - x;
237 statistics.last_played_qd += q * q * n / (n + 1);
239 statistics.last_played_sum += x;
242 s = statistics.num_played_sum;
244 q = (x > s / n)? x - s / n : s / n - x;
245 statistics.num_played_qd += q * q * n / (n + 1);
247 statistics.num_played_sum += x;
252 static int del_afs_statistics(const struct osl_row *row)
254 uint64_t n, s, q, a, new_s;
255 struct afs_info afsi;
257 ret = get_afsi_of_row(row, &afsi);
263 memset(&statistics, 0, sizeof(statistics));
267 s = statistics.last_played_sum;
268 q = statistics.last_played_qd;
269 a = afsi.last_played;
271 statistics.last_played_sum = new_s;
272 statistics.last_played_qd = q + s * s / n - a * a
273 - new_s * new_s / (n - 1);
275 s = statistics.num_played_sum;
276 q = statistics.num_played_qd;
279 statistics.num_played_sum = new_s;
280 statistics.num_played_qd = q + s * s / n - a * a
281 - new_s * new_s / (n - 1);
288 * At mood open time we determine the set of admissible files for the given
289 * mood where each file is identified by a pointer to a row of the audio file
290 * table. In the first pass the pointers are added to a temporary array and
291 * statistics are computed. When all admissible files have been processed in
292 * this way, the score of each admissible file is computed and the (row, score)
293 * pair is added to the score table. This has to be done in a second pass
294 * since the score depends on the statistics. Finally, the array is freed.
296 struct admissible_array {
297 /** Files are admissible wrt. this mood. */
299 /** The size of the array */
301 /** Pointer to the array of admissible files. */
302 struct osl_row **array;
306 * Check whether the given audio file is admissible. If it is, add it to array
307 * of admissible files.
309 static int add_if_admissible(struct osl_row *aft_row, void *data)
311 struct admissible_array *aa = data;
314 ret = row_is_admissible(aft_row, aa->m);
317 if (statistics.num >= aa->size) {
320 aa->array = para_realloc(aa->array,
321 aa->size * sizeof(struct osl_row *));
323 aa->array[statistics.num] = aft_row;
324 return add_afs_statistics(aft_row);
328 * Compute the new quadratic deviation in case one element changes.
330 * \param n Number of elements.
331 * \param old_qd The quadratic deviation before the change.
332 * \param old_val The value that was replaced.
333 * \param new_val The replacement value.
334 * \param old_sum The sum of all elements before the update.
336 * \return The new quadratic deviation resulting from replacing old_val
339 * Given n real numbers a_1, ..., a_n, their sum S = a_1 + ... + a_n,
340 * their quadratic deviation
342 * q = (a_1 - S/n)^2 + ... + (a_n - S/n)^2,
344 * and a real number b, the quadratic deviation q' of a_1,...a_{n-1}, b (ie.
345 * the last number a_n was replaced by b) may be computed in O(1) time in terms
346 * of n, q, a_n, b, and S as
348 * q' = q + d * s - (2 * S + d) * d / n
349 * = q + d * (s - 2 * S / n - d /n),
351 * where d = b - a_n, and s = b + a_n.
353 * Example: n = 3, a_1 = 3, a_2 = 5, a_3 = 7, b = 10. Then S = 15, q = 8, d = 3,
356 * q + d * s - (2 * S + d) * d / n = 8 + 51 - 33 = 26,
358 * which equals q' = (3 - 6)^2 + (5 - 6)^2 + (10 - 6)^2.
361 _static_inline_ int64_t update_quadratic_deviation(int64_t n, int64_t old_qd,
362 int64_t old_val, int64_t new_val, int64_t old_sum)
364 int64_t delta = new_val - old_val;
365 int64_t sigma = new_val + old_val;
366 return old_qd + delta * (sigma - 2 * old_sum / n - delta / n);
369 static int update_afs_statistics(struct afs_info *old_afsi,
370 struct afs_info *new_afsi)
373 int ret = get_num_admissible_files(&n);
379 statistics.last_played_qd = update_quadratic_deviation(n,
380 statistics.last_played_qd, old_afsi->last_played,
381 new_afsi->last_played, statistics.last_played_sum);
382 statistics.last_played_sum += new_afsi->last_played - old_afsi->last_played;
384 statistics.num_played_qd = update_quadratic_deviation(n,
385 statistics.num_played_qd, old_afsi->num_played,
386 new_afsi->num_played, statistics.num_played_sum);
387 statistics.num_played_sum += new_afsi->num_played - old_afsi->num_played;
391 static int add_to_score_table(const struct osl_row *aft_row)
394 struct afs_info afsi;
395 int ret = get_afsi_of_row(aft_row, &afsi);
399 score = compute_score(&afsi);
400 return score_add(aft_row, score);
403 static int delete_from_statistics_and_score_table(const struct osl_row *aft_row)
405 int ret = del_afs_statistics(aft_row);
408 return score_delete(aft_row);
412 * Delete one entry from the statistics and from the score table.
414 * \param aft_row The audio file which is no longer admissible.
416 * \return Positive on success, negative on errors.
418 * \sa \ref score_delete().
420 static int mood_delete_audio_file(const struct osl_row *aft_row)
424 ret = row_belongs_to_score_table(aft_row, NULL);
427 if (!ret) /* not admissible, nothing to do */
429 return delete_from_statistics_and_score_table(aft_row);
433 * Compute the new score of an audio file wrt. the current mood.
435 * \param aft_row Determines the audio file.
436 * \param old_afsi The audio file selector info before updating.
438 * The \a old_afsi argument may be \p NULL which indicates that no changes to
439 * the audio file info were made.
441 * \return Positive on success, negative on errors.
443 static int mood_update_audio_file(const struct osl_row *aft_row,
444 struct afs_info *old_afsi)
447 int ret, is_admissible, was_admissible = 0;
448 struct afs_info afsi;
452 return 1; /* nothing to do */
453 ret = row_belongs_to_score_table(aft_row, &rank);
456 was_admissible = ret;
457 ret = row_is_admissible(aft_row, current_mood);
460 is_admissible = (ret > 0);
461 if (!was_admissible && !is_admissible)
463 if (was_admissible && !is_admissible)
464 return delete_from_statistics_and_score_table(aft_row);
465 if (!was_admissible && is_admissible) {
466 ret = add_afs_statistics(aft_row);
469 return add_to_score_table(aft_row);
472 ret = get_afsi_of_row(aft_row, &afsi);
476 ret = update_afs_statistics(old_afsi, &afsi);
480 score = compute_score(&afsi);
481 PARA_DEBUG_LOG("score: %li\n", score);
482 percent = (score + 100) / 3;
485 else if (percent < 0)
487 PARA_DEBUG_LOG("moving from rank %u to %li%%\n", rank, percent);
488 return score_update(aft_row, percent);
491 static void log_statistics(void)
493 unsigned n = statistics.num;
494 int mean_days, sigma_days;
496 * We can not use the "now" pointer from sched.c here because we are
497 * called before schedule(), which initializes "now".
501 assert(current_mood);
502 PARA_NOTICE_LOG("loaded mood %s\n", current_mood->name?
503 current_mood->name : "(dummy)");
505 PARA_WARNING_LOG("no admissible files\n");
508 PARA_NOTICE_LOG("%u admissible files\n", statistics.num);
509 clock_get_realtime(&rnow);
510 mean_days = (rnow.tv_sec - statistics.last_played_sum / n) / 3600 / 24;
511 sigma_days = int_sqrt(statistics.last_played_qd / n) / 3600 / 24;
512 PARA_NOTICE_LOG("last_played mean/sigma: %d/%d days\n", mean_days, sigma_days);
513 PARA_NOTICE_LOG("num_played mean/sigma: %llu/%llu\n",
514 (long long unsigned)statistics.num_played_sum / n,
515 (long long unsigned)int_sqrt(statistics.num_played_qd / n));
519 * Close the current mood.
521 * Frees all resources of the current mood.
523 void close_current_mood(void)
525 destroy_mood(current_mood);
527 memset(&statistics, 0, sizeof(statistics));
531 * Change the current mood.
533 * \param mood_name The name of the mood to open.
534 * \param errmsg Error description is returned here.
536 * If \a mood_name is \a NULL, load the dummy mood that accepts every audio file
537 * and uses a scoring method based only on the \a last_played information.
539 * The errmsg pointer may be NULL, in which case no error message will be
540 * returned. If a non-NULL pointer is given, the caller must free *errmsg.
542 * If there is already an open mood, it will be closed first.
544 * \return Positive on success, negative on errors. Loading the dummy mood
547 * \sa struct \ref afs_info::last_played, \ref mp_eval_row().
549 int change_current_mood(const char *mood_name, char **errmsg)
552 struct admissible_array aa = {
560 struct osl_object obj = {
561 .data = (char *)mood_name,
562 .size = strlen(mood_name) + 1
564 ret = osl(osl_get_row(moods_table, BLOBCOL_NAME, &obj, &row));
567 *errmsg = make_message("no such mood: %s",
571 ret = load_mood(row, &m, errmsg);
574 close_current_mood();
576 } else { /* load dummy mood */
577 close_current_mood();
578 current_mood = alloc_new_mood(NULL);
581 PARA_NOTICE_LOG("computing statistics of admissible files\n");
582 ret = audio_file_loop(&aa, add_if_admissible);
585 *errmsg = make_message("audio file loop failed");
588 for (i = 0; i < statistics.num; i++) {
589 ret = add_to_score_table(aa.array[i]);
592 *errmsg = make_message(
593 "could not add row to score table");
598 ret = statistics.num;
605 * Close and re-open the current mood.
607 * This function is called on events which render the current list of
608 * admissible files useless, for example if an attribute is removed from the
611 * If no mood is currently open, the function returns success.
613 static int reload_current_mood(void)
616 char *mood_name = NULL;
618 ret = clear_score_table();
623 PARA_NOTICE_LOG("reloading %s\n", current_mood->name?
624 current_mood->name : "(dummy)");
625 if (current_mood->name)
626 mood_name = para_strdup(current_mood->name);
627 close_current_mood();
628 ret = change_current_mood(mood_name, NULL);
634 * Notification callback for the moods table.
636 * \param event Type of the event just occurred.
638 * \param data Its type depends on the event.
640 * This function performs actions required due to the occurrence of the given
641 * event. Possible actions include reload of the current mood and update of the
642 * score of an audio file.
646 int moods_event_handler(enum afs_events event, __a_unused struct para_buffer *pb,
653 * The three blob events might change the set of admissible files,
654 * so we must reload the score list.
659 if (data == moods_table || data == playlists_table)
660 return 1; /* no reload necessary for these */
661 return reload_current_mood();
662 /* these also require reload of the score table */
664 case ATTRIBUTE_REMOVE:
665 case ATTRIBUTE_RENAME:
666 return reload_current_mood();
667 /* changes to the aft only require to re-examine the audio file */
669 struct afsi_change_event_data *aced = data;
670 return mood_update_audio_file(aced->aft_row, aced->old_afsi);
673 case AUDIO_FILE_RENAME:
675 return mood_update_audio_file(data, NULL);
676 case AUDIO_FILE_REMOVE:
677 return mood_delete_audio_file(data);