playlist.c

   1 #include "para.h"
   2 #include "error.h"
   3 #include "afh.h"
   4 #include "afs.h"
   5 #include "string.h"
   6
   7 /** \file playlist.c Functions for loading and saving playlists. */
   8
   9 /** Structure used for adding entries to a playlist. */
  10 struct playlist_info {
  11         /** The name of the playlist. */
  12         char *name;
  13         /** The number of entries currently in the playlist. */
  14         unsigned length;
  15 };
  16 static struct playlist_info current_playlist;
  17
  18 /**
  19  * Re-insert an audio file into the tree of admissible files.
  20  *
  21  * \param aft_row Determines the audio file.
  22  *
  23  * \return The return value of score_update().
  24  */
  25 int playlist_update_audio_file(struct osl_row *aft_row)
  26 {
  27         /* always re-insert to the top of the tree */
  28         return score_update(aft_row, 0);
  29 }
  30
  31 static int add_playlist_entry(char *line, void *data)
  32 {
  33         struct playlist_info *playlist = data;
  34         struct osl_row *aft_row;
  35         int ret = aft_get_row_of_path(line, &aft_row);
  36
  37         if (ret < 0) {
  38                 PARA_NOTICE_LOG("path not found in audio file table: %s\n",
  39                         line);
  40                 return 1;
  41         }
  42         ret = score_add(aft_row, -playlist->length);
  43         if (ret < 0) {
  44                 PARA_ERROR_LOG("failed to add %s: %d\n", line, ret);
  45                 return ret;
  46         }
  47         playlist->length++;
  48         return 1;
  49 }
  50
  51 static int load_playlist(struct osl_row *row, struct playlist_info *playlist)
  52 {
  53         struct osl_object obj;
  54         int ret;
  55
  56         ret = osl_get_object(playlists_table, row, BLOBCOL_NAME, &obj);
  57         if (ret < 0)
  58                 return ret;
  59         playlist->name = para_strdup(obj.data);
  60         playlist->length = 0;
  61         ret = osl_open_disk_object(playlists_table, row, BLOBCOL_DEF, &obj);
  62         if (ret < 0)
  63                 goto err;
  64         ret = for_each_line_ro(obj.data, obj.size, add_playlist_entry,
  65                 playlist);
  66         osl_close_disk_object(&obj);
  67         if (ret < 0)
  68                 goto err;
  69         ret = -E_PLAYLIST_EMPTY;
  70         if (!playlist->length)
  71                 goto err;
  72         PARA_NOTICE_LOG("loaded playlist %s (%u files)\n", playlist->name,
  73                 playlist->length);
  74         return 1;
  75 err:
  76         free(playlist->name);
  77         return ret;
  78 }
  79
  80 /* returns -E_PLAYLIST_LOADED on _success_ to terminate the loop */
  81 static int playlist_loop(struct osl_row *row, void *data)
  82 {
  83         struct playlist_info *playlist = data;
  84         int ret = load_playlist(row, playlist);
  85         if (ret < 0) {
  86                 if (ret != -E_DUMMY_ROW)
  87                         PARA_NOTICE_LOG("unable to load playlist, trying next\n");
  88                 return 1;
  89         }
  90         return -E_PLAYLIST_LOADED;
  91 }
  92
  93 static int load_first_available_playlist(struct playlist_info *playlist)
  94 {
  95         int ret = osl_rbtree_loop(playlists_table, BLOBCOL_NAME, playlist,
  96                 playlist_loop);
  97         if (ret == -E_PLAYLIST_LOADED) /* success */
  98                 return 1;
  99         if (ret < 0)
 100                 return ret; /* error */
 101         PARA_NOTICE_LOG("no valid playlist found\n");
 102         return -E_NO_PLAYLIST;
 103 }
 104
 105 /**
 106  * Close the current playlist.
 107  *
 108  * \sa playlist_open().
 109  */
 110 void playlist_close(void)
 111 {
 112         free(current_playlist.name);
 113         current_playlist.name = NULL;
 114 }
 115
 116 /**
 117  * Open the given playlist.
 118  *
 119  * \param name The name of the playlist to open.
 120  *
 121  * If name is \p NULL, load the first available playlist. Files which are
 122  * listed in the playlist, but not contained in the database are ignored.
 123  * This is not considered an error.
 124  *
 125  * \return Positive on success, negative on errors. Possible errors
 126  * include: Given playlist not found, -E_NO_PLAYLIST (no playlist defined).
 127  */
 128 int playlist_open(char *name)
 129 {
 130         struct osl_object obj;
 131         int ret;
 132         struct osl_row *row;
 133
 134         if (!name)
 135                 return load_first_available_playlist(&current_playlist);
 136         obj.data = name;
 137         obj.size = strlen(obj.data);
 138         ret = osl_get_row(playlists_table, BLOBCOL_NAME, &obj, &row);
 139         if (ret < 0) {
 140                 PARA_NOTICE_LOG("failed to load playlist %s\n", name);
 141                 return ret;
 142         }
 143         return load_playlist(row, &current_playlist);
 144 }