score.c

   1 /*
   2  * Copyright (C) 2007 Andre Noll <maan@systemlinux.org>
   3  *
   4  * Licensed under the GPL v2. For licencing details see COPYING.
   5  */
   6
   7 /** \file score.c Scoring functions to determine the audio file streaming order. */
   8 #include "para.h"
   9 #include "error.h"
  10 #include "afh.h"
  11 #include "afs.h"
  12 #include "list.h"
  13 #include "string.h"
  14
  15 int mood_compute_score(const void *row, long *score);
  16
  17 static void *score_table;
  18
  19 static int ptr_compare(const struct osl_object *obj1, const struct osl_object *obj2)
  20 {
  21         void *d1 = *(void **)obj1->data;
  22         void *d2 = *(void **)obj2->data;
  23         return NUM_COMPARE(d1, d2);
  24 }
  25
  26 /**
  27  * Compare the score of two audio files
  28  *
  29  * \param obj1 Pointer to the first score object.
  30  * \param obj2 Pointer to the second score object.
  31  *
  32  * This function first compares the score values as usual integers. If they compare as
  33  * equal, the addresss of \a obj1 and \a obj2 are compared. So this compare function
  34  * returns zero if and only if \a obj1 and \a obj2 point to the same memory area.
  35  *
  36  * \sa osl_compare_function.
  37  */
  38 static int score_compare(const struct osl_object *obj1, const struct osl_object *obj2)
  39 {
  40         int d1 = *(int*)obj1->data;
  41         int d2 = *(int*)obj2->data;
  42         int ret = NUM_COMPARE(d2, d1);
  43
  44         if (ret)
  45                 return ret;
  46         return NUM_COMPARE(obj2->data, obj1->data);
  47 }
  48
  49 /**
  50  * The score table consists of two colums: The \a aft_row column contains
  51  * pointers to the rows of the audio file table,  and the score column contains
  52  * the current score of the audio file associated with that row.
  53  */
  54 enum score_table_columns {
  55         /** The row of the audio file. */
  56         SCORECOL_AFT_ROW,
  57         /** The score */
  58         SCORECOL_SCORE,
  59         /** This table has two columns */
  60         NUM_SCORE_COLUMNS
  61 };
  62
  63 static struct osl_column_description score_cols[] = {
  64         [SCORECOL_AFT_ROW] = {
  65                 .storage_type = OSL_NO_STORAGE,
  66                 .storage_flags = OSL_RBTREE | OSL_FIXED_SIZE | OSL_UNIQUE,
  67                 .name = "aft_row",
  68                 .compare_function = ptr_compare,
  69                 .data_size = sizeof(void *)
  70         },
  71         [SCORECOL_SCORE] = {
  72                 .storage_type = OSL_NO_STORAGE,
  73                 .storage_flags = OSL_RBTREE | OSL_FIXED_SIZE,
  74                 .name = "score",
  75                 .compare_function = score_compare,
  76                 .data_size = sizeof(long)
  77         }
  78 };
  79
  80 static struct osl_table_description score_table_desc = {
  81         .dir = DATABASE_DIR,
  82         .name = "score",
  83         .num_columns = NUM_SCORE_COLUMNS,
  84         .flags = 0,
  85         .column_descriptions = score_cols
  86 };
  87
  88 /**
  89  * Compute the number of files in score table.
  90  *
  91  * \param num Result is returned here.
  92  *
  93  * \return Positive on success, negative on errors.
  94  *
  95  * \sa osl_get_num_rows().
  96  */
  97 int get_num_admissible_files(unsigned *num)
  98 {
  99         return osl_get_num_rows(score_table, num);
 100 }
 101
 102 /**
 103  * Get the score of the audio file associated with given row of the score table.
 104  *
 105  * \param score_row Pointer to the row in the score table.
 106  * \param score Result is returned here on success.
 107  *
 108  * On errors (negative return value) the content of \a score is undefined.
 109  *
 110  * \return The return value of the underlying call to osl_get_object().
 111  */
 112 static int get_score_of_row(void *score_row, long *score)
 113 {
 114         struct osl_object obj;
 115         int ret = osl_get_object(score_table, score_row, SCORECOL_SCORE, &obj);
 116
 117         if (ret >= 0)
 118                 *score = *(long *)obj.data;
 119         return ret;
 120 }
 121
 122 /**
 123  * Add an entry to the table of admissible files.
 124  *
 125  * \param aft_row The audio file to be added.
 126  * \param score The score for this file.
 127  *
 128  * \return The return value of the underlying call to osl_add_row().
 129  */
 130 int score_add(const struct osl_row *aft_row, long score)
 131 {
 132         int ret;
 133         struct osl_object score_objs[NUM_SCORE_COLUMNS];
 134         size_t size;
 135
 136         assert(aft_row);
 137         size = score_table_desc.column_descriptions[SCORECOL_AFT_ROW].data_size;
 138         score_objs[SCORECOL_AFT_ROW].data = para_malloc(size);
 139         score_objs[SCORECOL_AFT_ROW].size = size;
 140         *(const void **)(score_objs[SCORECOL_AFT_ROW].data) = aft_row;
 141
 142         size = score_table_desc.column_descriptions[SCORECOL_SCORE].data_size;
 143         score_objs[SCORECOL_SCORE].data = para_malloc(size);
 144         score_objs[SCORECOL_SCORE].size = size;
 145         *(int *)(score_objs[SCORECOL_SCORE].data) = score;
 146
 147 //      PARA_DEBUG_LOG("adding %p\n", *(void **) (score_objs[SCORECOL_AFT_ROW].data));
 148         ret = osl_add_row(score_table, score_objs);
 149         if (ret < 0) {
 150                 PARA_ERROR_LOG("failed to add row: %d\n", ret);
 151                 free(score_objs[SCORECOL_AFT_ROW].data);
 152                 free(score_objs[SCORECOL_SCORE].data);
 153         }
 154         return ret;
 155 }
 156
 157 static int get_nth_score(unsigned n, long *score)
 158 {
 159         struct osl_row *row;
 160         int ret = osl_get_nth_row(score_table, SCORECOL_SCORE, n, &row);
 161
 162         if (ret < 0)
 163                 return ret;
 164         return get_score_of_row(row, score);
 165 }
 166
 167 /**
 168  * Replace a row of the score table.
 169  *
 170  * \param aft_row Determines the audio file to change.
 171  * \param percent The position to re-insert the audio file.
 172  *
 173  * The percent paramenter must be between \p 0 and 100 and. A value of zero
 174  * means to re-insert the audio file into the score table with a score lower
 175  * than any other admissible file.
 176  *
 177  * \return Positive on success, negative on errors. Possible errors: Errors
 178  * returned by osl_get_row(), get_num_admissible_files(), osl_get_nth_row(),
 179  * osl_get_object(), osl_update_object().
 180  */
 181 int score_update(const struct osl_row *aft_row, long percent)
 182 {
 183         struct osl_row *row;
 184         long new_score;
 185         unsigned n, new_pos;
 186         struct osl_object obj = {.data = &aft_row, .size = sizeof(void **)};
 187         int ret = osl_get_row(score_table, SCORECOL_AFT_ROW, &obj, &row);
 188
 189         if (ret < 0)
 190                 return ret;
 191         ret = get_num_admissible_files(&n);
 192         if (ret < 0)
 193                 return ret;
 194         new_pos = 1 + (n - 1) * percent / 100;
 195         ret = get_nth_score(new_pos, &new_score);
 196         if (ret < 0)
 197                 return ret;
 198         new_score--;
 199         obj.size = sizeof(long);
 200         obj.data = para_malloc(obj.size);
 201         *(long *)obj.data = new_score;
 202         PARA_NOTICE_LOG("new score: %ld, position: %u/%u\n", new_score,
 203                 new_pos, n);
 204         return osl_update_object(score_table, row, SCORECOL_SCORE, &obj);
 205 }
 206
 207 /**
 208  * Given an admissible file, get the corresponding row in the aft and the score.
 209  *
 210  * \param score_row Determines the admissible file.
 211  * \param score Result pointer.
 212  * \param aft_row Result pointer.
 213  *
 214  * \return Negative on errors, positive on success. Possible errors: Errors
 215  * returned by osl_get_object().
 216  */
 217 int get_score_and_aft_row(struct osl_row *score_row, long *score,
 218                 struct osl_row **aft_row)
 219 {
 220         struct osl_object obj;
 221         int ret = get_score_of_row(score_row, score);
 222
 223         if (ret < 0)
 224                 return ret;
 225         ret = osl_get_object(score_table, score_row, SCORECOL_AFT_ROW, &obj);
 226         if (ret < 0)
 227                 return ret;
 228         *aft_row = *(void **)obj.data;
 229         return 1;
 230 }
 231
 232 static int get_score_row_from_aft_row(const struct osl_row *aft_row,
 233                 struct osl_row **score_row)
 234 {
 235         struct osl_object obj = {.data = &aft_row, .size = sizeof(void **)};
 236         return osl_get_row(score_table, SCORECOL_AFT_ROW, &obj, score_row);
 237
 238 }
 239
 240 /**
 241  * Loop over all files in the score table.
 242  *
 243  * \param data A pointer to arbitrary data.
 244  * \param func Function to be called for each admissible file.
 245  *
 246  * \return The return value of the underlying call to osl_rbtree_loop().
 247  *
 248  * This is used for the ls command. The \a data parameter is passed as the
 249  * second argument to \a func.
 250  *
 251  * \sa admissible_file_loop_reverse().
 252  */
 253 int admissible_file_loop(void *data, osl_rbtree_loop_func *func)
 254 {
 255         return osl_rbtree_loop(score_table, SCORECOL_SCORE, data, func);
 256 }
 257
 258 /**
 259  * Loop over all files in the score table in reverse order.
 260  *
 261  * \param data As in admissible_file_loop().
 262  * \param func As in admissible_file_loop().
 263  *
 264  * \return Same return value as admissible_file_loop().
 265  *
 266  * \sa admissible_file_loop(), osl_rbtree_loop_reverse().
 267  */
 268 int admissible_file_loop_reverse(void *data, osl_rbtree_loop_func *func)
 269 {
 270         return osl_rbtree_loop_reverse(score_table, SCORECOL_SCORE, data, func);
 271 }
 272
 273 /**
 274  * Get the admissible audio file with highest score.
 275  *
 276  * \param aft_row Points to the row in the aft of the "best" audio file.
 277  * \param score Highest score value in the score table.
 278  *
 279  * \return Positive on success, negative on errors. Possible errors: Errors
 280  * returned by osl_rbtree_last_row(), osl_get_object().
 281  */
 282 int score_get_best(struct osl_row **aft_row, long *score)
 283 {
 284         struct osl_row *row;
 285         struct osl_object obj;
 286         int ret = osl_rbtree_last_row(score_table, SCORECOL_SCORE, &row);
 287
 288         if (ret < 0)
 289                 return ret;
 290         ret = osl_get_object(score_table, row, SCORECOL_AFT_ROW, &obj);
 291         if (ret < 0)
 292                 return ret;
 293         *aft_row = *(void **)obj.data;
 294         return get_score_of_row(row, score);
 295 }
 296
 297 /**
 298  * Remove an entry from the rbtree of admissible files.
 299  *
 300  * \param aft_row The file which is no longer admissible.
 301  *
 302  * \return Positive on success, negative on errors. Possible errors:
 303  * Errors returned by osl_get_row() and osl_del_row().
 304  *
 305  * \sa score_add(), score_shutdown().
 306  */
 307 int score_delete(const struct osl_row *aft_row)
 308 {
 309         struct osl_row *score_row;
 310         int ret = get_score_row_from_aft_row(aft_row, &score_row);
 311
 312         if (ret < 0)
 313                 return ret;
 314         return osl_del_row(score_table, score_row);
 315 }
 316
 317 /**
 318  * Find out whether an audio file is contained in the score table.
 319  *
 320  * \param aft_row The row of the audio file table.
 321  *
 322  * \return Positive, if \a aft_row belongs to the audio file table,
 323  * zero if not, negative on errors.
 324  */
 325 int row_belongs_to_score_table(const struct osl_row *aft_row)
 326 {
 327         struct osl_row *score_row;
 328         int ret = get_score_row_from_aft_row(aft_row, &score_row);
 329         if (ret >= 0)
 330                 return 1;
 331         if (ret == -E_RB_KEY_NOT_FOUND)
 332                 return 0;
 333         return ret;
 334 }
 335
 336 /**
 337  * Close the score table.
 338  *
 339  * \param flags Options passed to osl_close_table().
 340  *
 341  * \sa score_init().
 342  */
 343 void score_shutdown(enum osl_close_flags flags)
 344 {
 345         osl_close_table(score_table, flags | OSL_FREE_VOLATILE);
 346 }
 347
 348 /**
 349  * Init the scoring subsystem.
 350  *
 351  * \param ti Gets filled in by the function.
 352  *
 353  * \return The return value of the underlying call to osl_open_table().
 354  *
 355  * \sa score_shutdown().
 356  */
 357 int score_init(struct table_info *ti)
 358 {
 359         ti->desc = &score_table_desc;
 360         ti->flags = TBLFLAG_SKIP_CREATE;
 361         int ret = osl_open_table(ti->desc, &ti->table);
 362
 363         score_table = ti->table;
 364         return ret;
 365 }