playlist.c

   1 /* Copyright (C) 2007 Andre Noll <maan@tuebingen.mpg.de>, see file COPYING. */
   2
   3 #include <regex.h>
   4 #include <osl.h>
   5 #include <lopsub.h>
   6
   7 #include "para.h"
   8 #include "error.h"
   9 #include "string.h"
  10 #include "afh.h"
  11 #include "afs.h"
  12 #include "ipc.h"
  13 #include "sideband.h"
  14
  15 /** \file playlist.c Functions for loading and saving playlists. */
  16
  17 /** Structure used for adding entries to a playlist. */
  18 struct playlist_instance {
  19         /** The name of the playlist. */
  20         char *name;
  21         /** The number of entries currently in the playlist. */
  22         unsigned length;
  23 };
  24 static struct playlist_instance current_playlist;
  25
  26 /**
  27  * Re-insert an audio file into the tree of admissible files.
  28  *
  29  * \param aft_row Determines the audio file.
  30  *
  31  * \return The return value of score_update().
  32  */
  33 static int playlist_update_audio_file(const struct osl_row *aft_row)
  34 {
  35         /* always re-insert to the top of the tree */
  36         return score_update(aft_row, 0);
  37 }
  38
  39 static int add_playlist_entry(char *path, void *data)
  40 {
  41         struct playlist_instance *playlist = data;
  42         struct osl_row *aft_row;
  43         int ret = aft_get_row_of_path(path, &aft_row);
  44
  45         if (ret < 0) {
  46                 PARA_NOTICE_LOG("%s: %s\n", path, para_strerror(-ret));
  47                 return 1;
  48         }
  49         ret = score_add(aft_row, -playlist->length);
  50         if (ret < 0) {
  51                 PARA_ERROR_LOG("failed to add %s: %s\n", path, para_strerror(-ret));
  52                 return ret;
  53         }
  54         playlist->length++;
  55         return 1;
  56 }
  57
  58 static int check_playlist_path(char *path, void *data)
  59 {
  60         struct afs_callback_arg *aca = data;
  61         struct osl_row *aft_row;
  62         int ret = aft_get_row_of_path(path, &aft_row);
  63
  64         if (ret < 0)
  65                 afs_error(aca, "%s: %s\n", path, para_strerror(-ret));
  66         return 1; /* do not fail the loop on bad paths */
  67 }
  68
  69 static int check_playlist(struct osl_row *row, void *data)
  70 {
  71         struct afs_callback_arg *aca = data;
  72         struct para_buffer *pb = &aca->pbout;
  73         struct osl_object playlist_def;
  74         char *playlist_name;
  75         int ret = pl_get_name_and_def_by_row(row, &playlist_name, &playlist_def);
  76
  77         if (ret < 0) { /* log error, but continue */
  78                 afs_error(aca, "failed to get playlist data: %s\n",
  79                         para_strerror(-ret));
  80                 return 1;
  81         }
  82         if (*playlist_name) { /* skip dummy row */
  83                 para_printf(pb, "checking playlist %s...\n", playlist_name);
  84                 for_each_line(FELF_READ_ONLY, playlist_def.data,
  85                         playlist_def.size, check_playlist_path, aca);
  86         }
  87         osl_close_disk_object(&playlist_def);
  88         return 1;
  89 }
  90
  91 /**
  92  * Check the playlist table for inconsistencies.
  93  *
  94  * \param aca This callback ignores ->query.
  95  *
  96  * \return Standard. Invalid paths are reported, but are not considered an
  97  * error.
  98  */
  99 int playlist_check_callback(struct afs_callback_arg *aca)
 100 {
 101         para_printf(&aca->pbout, "checking playlists...\n");
 102         return osl(osl_rbtree_loop(playlists_table, BLOBCOL_ID, aca,
 103                 check_playlist));
 104 }
 105
 106 /** Free all resources of the current playlist, if any. */
 107 void playlist_unload(void)
 108 {
 109         if (!current_playlist.name)
 110                 return;
 111         free(current_playlist.name);
 112         current_playlist.name = NULL;
 113         current_playlist.length = 0;
 114 }
 115
 116 /**
 117  * Populate the score table from the paths of a playlist database object.
 118  *
 119  * This loads the blob object which corresponds to the given name from the
 120  * playlist table. Each line of the blob is regarded as a path which is looked
 121  * up in the audio file table. If the path lookup succeeds, a reference to the
 122  * corresponding row of the audio file table is added to the score table.
 123  *
 124  * \param name The name of the playlist to load.
 125  * \param msg Error message or playlist info is returned here.
 126  *
 127  * \return The length of the loaded playlist on success, negative error code
 128  * else. Files which are listed in the playlist, but are not contained in the
 129  * database are ignored. This is not considered an error.
 130  */
 131 int playlist_load(const char *name, char **msg)
 132 {
 133         int ret;
 134         struct playlist_instance *playlist = &current_playlist;
 135         struct osl_object playlist_def;
 136
 137         ret = pl_get_def_by_name(name, &playlist_def);
 138         if (ret < 0) {
 139                 *msg = make_message("could not read playlist %s\n", name);
 140                 return ret;
 141         }
 142         playlist_unload();
 143         ret = for_each_line(FELF_READ_ONLY, playlist_def.data,
 144                 playlist_def.size, add_playlist_entry, playlist);
 145         osl_close_disk_object(&playlist_def);
 146         if (ret < 0)
 147                 goto err;
 148         ret = -E_PLAYLIST_EMPTY;
 149         if (!playlist->length)
 150                 goto err;
 151         playlist->name = para_strdup(name);
 152         *msg = make_message("loaded playlist %s (%u files)\n", playlist->name,
 153                 playlist->length);
 154         /* success */
 155         return current_playlist.length;
 156 err:
 157         PARA_NOTICE_LOG("unable to load playlist %s\n", name);
 158         *msg = make_message("unable to load playlist %s\n", name);
 159         return ret;
 160 }
 161
 162 static int search_path(char *path, void *data)
 163 {
 164         if (strcmp(path, data))
 165                 return 1;
 166         return -E_PATH_FOUND;
 167 }
 168
 169 static int handle_audio_file_event(enum afs_events event, void *data)
 170 {
 171         int ret;
 172         bool was_admissible = false, is_admissible;
 173         struct osl_object playlist_def;
 174         char *new_path;
 175         const struct osl_row *row = data;
 176
 177         if (event == AUDIO_FILE_RENAME)
 178                 was_admissible = row_belongs_to_score_table(row);
 179         ret = get_audio_file_path_of_row(row, &new_path);
 180         if (ret < 0)
 181                 return ret;
 182         ret = pl_get_def_by_name(current_playlist.name, &playlist_def);
 183         if (ret < 0)
 184                 return ret;
 185         ret = for_each_line(FELF_READ_ONLY, playlist_def.data,
 186                 playlist_def.size, search_path, new_path);
 187         osl_close_disk_object(&playlist_def);
 188         is_admissible = (ret < 0);
 189         if (was_admissible && is_admissible)
 190                 return 1;
 191         if (!was_admissible && !is_admissible)
 192                 return 1;
 193         if (was_admissible && !is_admissible) {
 194                 current_playlist.length--;
 195                 return score_delete(row);
 196         }
 197         /* !was_admissible && is_admissible */
 198         current_playlist.length++;
 199         return score_add(row, 0); /* play it immediately */
 200 }
 201
 202 /**
 203  * Handle afs events relevant to playlists.
 204  *
 205  * \param event The event type.
 206  * \param pb Unused.
 207  * \param data Depends on the event type.
 208  *
 209  * \return Standard.
 210  */
 211 int playlists_event_handler(enum afs_events event,
 212         __a_unused struct para_buffer *pb, void *data)
 213 {
 214         struct afsi_change_event_data *aced = data;
 215
 216         if (!current_playlist.name)
 217                 return 1;
 218         switch (event) {
 219         case AFSI_CHANGE:
 220                 return playlist_update_audio_file(aced->aft_row);
 221         case AUDIO_FILE_RENAME:
 222         case AUDIO_FILE_ADD:
 223                 return handle_audio_file_event(event, data);
 224         case AUDIO_FILE_REMOVE:
 225                 if (!row_belongs_to_score_table(data))
 226                         return 1;
 227                 current_playlist.length--;
 228                 return score_delete(data);
 229         default:
 230                 return 1;
 231         }
 232 }