afs.h

   1 /*
   2  * Copyright (C) 2007-2009 Andre Noll <maan@systemlinux.org>
   3  *
   4  * Licensed under the GPL v2. For licencing details see COPYING.
   5  */
   6
   7 /** \file afs.h Exported symbols of the audio file selector. */
   8
   9 #include <regex.h>
  10 #include "hash.h"
  11
  12 /** Audio file selector data stored in the audio file table. */
  13 struct afs_info {
  14         /** Seconds since the epoch. */
  15         uint64_t last_played;
  16         /** Bit field of set attributes. */
  17         uint64_t attributes;
  18         /** Counts how many times the file was selected. */
  19         uint32_t num_played;
  20         /** Image blob associated with this file (foreign key). */
  21         uint32_t image_id;
  22         /** Lyrics blob associated with this file (foreign key). */
  23         uint32_t lyrics_id;
  24         /** Mp3, ogg or aac. */
  25         uint8_t audio_format_id;
  26         /** Amplification value. */
  27         uint8_t amp;
  28 };
  29
  30 /**
  31  * Events caused by changes to an afs table.
  32  *
  33  * Whenever an afs table changes, an event is generated which causes afs to
  34  * call the event handlers of all other tables. For example, if an audio file
  35  * is added, the event handler of the mood table checks the new file for
  36  * admissibility.
  37  */
  38 enum afs_events {
  39         /** An attribute was added. */
  40         ATTRIBUTE_ADD,
  41         /** An attribute was renamed. */
  42         ATTRIBUTE_RENAME,
  43         /** An attribute was removed. */
  44         ATTRIBUTE_REMOVE,
  45         /** The afs info struct of an audio file changed. */
  46         AFSI_CHANGE,
  47         /** The afh info struct of an audio file changed. */
  48         AFHI_CHANGE,
  49         /** An audio file was renamed. */
  50         AUDIO_FILE_RENAME,
  51         /** An audio file was added. */
  52         AUDIO_FILE_ADD,
  53         /** An audio file is about to be removed. */
  54         AUDIO_FILE_REMOVE,
  55         /** A new blob was added. */
  56         BLOB_ADD,
  57         /** A blob was renamed. */
  58         BLOB_RENAME,
  59         /** A blob is about to be removed. */
  60         BLOB_REMOVE,
  61 };
  62
  63 /**
  64  * Used as data for \ref afs_event() for events of type \p ATTRIBUTE_ADD.
  65  */
  66 struct rmatt_event_data {
  67         /** The name of the attribute being added. */
  68         const char *name;
  69         /** Its bit number. */
  70         unsigned char bitnum;
  71 };
  72
  73 /**
  74  * Used as data for \ref afs_event() for events of type \p ATTRIBUTE_AFSI_CHANGE.
  75  */
  76 struct afsi_change_event_data {
  77         /** Pointer to the row that has changed. */
  78         struct osl_row *aft_row;
  79         /** Afs info before the change. */
  80         struct afs_info *old_afsi;
  81 };
  82
  83 /** Function pointers for table handling.  */
  84 struct afs_table {
  85         /** Initializes the other pointers in this struct. */
  86         void (*init)(struct afs_table *t);
  87         /** The name of this table. */
  88         const char *name;
  89         /** Gets called on startup and on \p SIGHUP. */
  90         int (*open)(const char *base_dir);
  91         /** Gets called on shutdown and on \p SIGHUP. */
  92         void (*close)(void);
  93         /** Called by the \a init afs command. */
  94         int (*create)(const char *);
  95         /** Handles afs events. */
  96         int (*event_handler)(enum afs_events event, struct para_buffer *pb,
  97                 void *data);
  98 };
  99
 100 /** How audio files are selected by afs. */
 101 enum play_mode {
 102         /** Admissible files are determined by a mood definition. */
 103         PLAY_MODE_MOOD,
 104         /** All listed files are admissible. */
 105         PLAY_MODE_PLAYLIST,
 106 };
 107
 108 /**
 109  * Data about one audio file.
 110  *
 111  * Needed to produce ls and stat output.
 112  */
 113 struct ls_data {
 114         /** Usual audio format handler information. */
 115         struct afh_info afhi;
 116         /** Audio file selector information. */
 117         struct afs_info afsi;
 118         /** The full path of the audio file. */
 119         char *path;
 120         /** The score value (if -a was given). */
 121         long score;
 122         /** The sha1 hash of audio file. */
 123         HASH_TYPE *hash;
 124 };
 125
 126 /** Data about the current audio file, passed from afs to server. */
 127 struct audio_file_data {
 128         /** The open file descriptor to the current audio file. */
 129         int fd;
 130         /** Vss needs this for streaming. */
 131         struct afh_info afhi;
 132 };
 133
 134 /**
 135  * Codes used for communication between the server and the afs process.
 136  *
 137  * Before forking the afs child, para_server creates a bidirectional pipe
 138  * through which both processes communicate. Usually para_server requests a new
 139  * audio in order to start streaming or when the end of the current audio file
 140  * has been reached.  The afs process responds to such a request by sending
 141  * back an eight byte buffer. The first four bytes is the uint32_t
 142  * representation of the code, usually \p NEXT_AUDIO_FILE if an admissible
 143  * audio file was found, successfully opened and verified. The other four bytes
 144  * represent the shared memory id of the shared memory area that contains
 145  * details about the audio file to be streamed next. The open file descriptor
 146  * of that file is also passed from afs to para_server through the same pipe.
 147  */
 148 enum afs_server_code {
 149         /** An audio file was successfully opened. */
 150         NEXT_AUDIO_FILE,
 151         /** No admissible audio file was found. */
 152         NO_ADMISSIBLE_FILES,
 153 };
 154
 155 /** Flags passed to for_each_matching_row(). */
 156 enum pattern_match_flags {
 157         /** Loop in reverse order. */
 158         PM_REVERSE_LOOP = 1,
 159         /** If no pattern is given, loop over all rows. */
 160         PM_NO_PATTERN_MATCHES_EVERYTHING = 2,
 161         /** If the data in match_column is the empty string, skip this row. */
 162         PM_SKIP_EMPTY_NAME = 4,
 163 };
 164
 165 /** Structure passed to for_each_matching_row(). */
 166 struct pattern_match_data {
 167         /** Loop over all rows in this table. */
 168         struct osl_table *table;
 169         /** Determines the loop order. Must be an rbtree column. */
 170         unsigned loop_col_num;
 171         /** Data from this column is matched against the given patterns. */
 172         unsigned match_col_num;
 173         /** \see pattern_match_flags. */
 174         unsigned pm_flags;
 175         /** This value is passed verbatim to fnmatch(). */
 176         int fnmatch_flags;
 177         /** Null-terminated array of patterns. */
 178         struct osl_object patterns;
 179         /** Data pointer passed to the action function. */
 180         void *data;
 181         /** For each matching row, this function will be called. */
 182         int (*action)(struct osl_table *table, struct osl_row *row, const char *name, void *data);
 183 };
 184
 185
 186 /**
 187  * Afs command handlers run as a process which is not related to the afs
 188  * process, i.e. they can not change the address space of afs directly.
 189  * Therefore afs commands typically consist of two functions: The command
 190  * handler and the corresponding callback function that runs in afs context.
 191  *
 192  * \sa send_callback_request().
 193  */
 194 typedef void callback_function(int fd, const struct osl_object *);
 195
 196 /**
 197  * Callbacks send chunks to data back to the command handler. Pointers to
 198  * this type of function are used by \ref send_callback_request and friends
 199  * to deal with the data in the command handler process.
 200  *
 201  * \sa \ref send_callback_request().
 202  */
 203 typedef int callback_result_handler(struct osl_object *result, void *private);
 204 int rc4_send_result(struct osl_object *result, void *private);
 205 int pass_buffer_as_shm(char *buf, size_t size, void *fd_ptr);
 206
 207 __noreturn void afs_init(uint32_t cookie, int socket_fd);
 208 void afs_event(enum afs_events event, struct para_buffer *pb,
 209         void *data);
 210 int send_callback_request(callback_function *f, struct osl_object *query,
 211                 callback_result_handler *result_handler,
 212                 void *private_result_data);
 213 int send_option_arg_callback_request(struct osl_object *options,
 214                 int argc,  char * const * const argv, callback_function *f,
 215                 callback_result_handler *result_handler,
 216                 void *private_result_data);
 217 int send_standard_callback_request(int argc,  char * const * const argv,
 218                 callback_function *f, callback_result_handler *result_handler,
 219                 void *private_result_data);
 220 int string_compare(const struct osl_object *obj1, const struct osl_object *obj2);
 221 int for_each_matching_row(struct pattern_match_data *pmd);
 222
 223 /* score */
 224 void score_init(struct afs_table *t);
 225 int admissible_file_loop(void *data, osl_rbtree_loop_func *func);
 226 int admissible_file_loop_reverse(void *data, osl_rbtree_loop_func *func);
 227 int score_get_best(struct osl_row **aft_row, long *score);
 228 int get_score_and_aft_row(struct osl_row *score_row, long *score, struct osl_row **aft_row);
 229 int score_add(const struct osl_row *row, long score);
 230 int score_update(const struct osl_row *aft_row, long new_score);
 231 int get_num_admissible_files(unsigned *num);
 232 int score_delete(const struct osl_row *aft_row);
 233 int clear_score_table(void);
 234 int row_belongs_to_score_table(const struct osl_row *aft_row, unsigned *rank);
 235
 236 /* attribute */
 237 void attribute_init(struct afs_table *t);
 238 void get_attribute_bitmap(const uint64_t *atts, char *buf); /* needed by com_ls() */
 239 int get_attribute_bitnum_by_name(const char *att_name, unsigned char *bitnum);
 240 int get_attribute_text(uint64_t *atts, const char *delim, char **text);
 241
 242 /* aft */
 243 void aft_init(struct afs_table *t);
 244 int aft_get_row_of_path(const char *path, struct osl_row **row);
 245 int open_and_update_audio_file(struct osl_row *aft_row, long score,
 246         struct audio_file_data *afd);
 247 int load_afd(int shmid, struct audio_file_data *afd);
 248 int load_afsi(struct afs_info *afsi, struct osl_object *obj);
 249 void save_afsi(struct afs_info *afsi, struct osl_object *obj);
 250 int get_afsi_of_row(const struct osl_row *row, struct afs_info *afsi);
 251 int get_afhi_of_row(const struct osl_row *row, struct afh_info *afhi);
 252 int get_afsi_of_path(const char *path, struct afs_info *afsi);
 253 int get_audio_file_path_of_row(const struct osl_row *row, char **path);
 254 int get_afsi_object_of_row(const struct osl_row *row, struct osl_object *obj);
 255 int audio_file_loop(void *private_data, osl_rbtree_loop_func *func);
 256 void aft_check_callback(int fd, __a_unused const struct osl_object *query);
 257
 258 /* playlist */
 259 int playlist_open(char *name);
 260 void playlist_close(void);
 261 void playlist_check_callback(int fd, __a_unused const struct osl_object *query);
 262
 263 /** evaluates to 1 if x < y, to -1 if x > y and to 0 if x == y */
 264 #define NUM_COMPARE(x, y) ((int)((x) < (y)) - (int)((x) > (y)))
 265
 266
 267 /** Define exported functions and a table pointer for an osl blob table. */
 268 #define DECLARE_BLOB_SYMBOLS(table_name, cmd_prefix) \
 269         void table_name ## _init(struct afs_table *t); \
 270         int cmd_prefix ## _get_name_by_id(uint32_t id, char **name); \
 271         int cmd_prefix ## _get_def_by_id(uint32_t id, struct osl_object *def); \
 272         int cmd_prefix ## _get_def_by_name(char *name, struct osl_object *def); \
 273         int cmd_prefix ## _get_name_and_def_by_row(const struct osl_row *row, \
 274                 char **name, struct osl_object *def); \
 275         int table_name ##_event_handler(enum afs_events event, \
 276                 struct para_buffer *pb, void *data); \
 277         extern struct osl_table *table_name ## _table;
 278
 279 DECLARE_BLOB_SYMBOLS(lyrics, lyr);
 280 DECLARE_BLOB_SYMBOLS(images, img);
 281 DECLARE_BLOB_SYMBOLS(moods, mood);
 282 DECLARE_BLOB_SYMBOLS(playlists, pl);
 283
 284 /** The columns of an abstract blob table. */
 285 enum blob_table_columns {
 286         /** The identifier, a positive integer that never repeats. */
 287         BLOBCOL_ID,
 288         /** The unique name of the blob. */
 289         BLOBCOL_NAME,
 290         /** The actual blob contents. */
 291         BLOBCOL_DEF,
 292         /** A blob table has that many columns. */
 293         NUM_BLOB_COLUMNS
 294 };