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 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 *private_data)
  32 {
  33         struct osl_row *aft_row;
  34         struct playlist_info *pli = private_data;
  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, -pli->length);
  43         if (ret < 0) {
  44                 PARA_ERROR_LOG("failed to add %s: %d\n", line, ret);
  45                 return ret;
  46         }
  47         pli->length++;
  48         return 1;
  49 }
  50
  51 static int load_playlist(struct osl_row *row)
  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, __a_unused void *private_data)
  82 {
  83         int ret = load_playlist(row);
  84         if (ret < 0) {
  85                 if (ret != -E_DUMMY_ROW)
  86                         PARA_NOTICE_LOG("unable to load playlist, trying next\n");
  87                 return 1;
  88         }
  89         return -E_PLAYLIST_LOADED;
  90 }
  91
  92 static int load_first_available_playlist(void)
  93 {
  94         int ret = osl_rbtree_loop(playlists_table, BLOBCOL_NAME, NULL,
  95                 playlist_loop);
  96         if (ret == -E_PLAYLIST_LOADED) /* success */
  97                 return 1;
  98         if (ret < 0)
  99                 return ret; /* error */
 100         PARA_NOTICE_LOG("no valid playlist found\n");
 101         return -E_NO_PLAYLIST;
 102 }
 103
 104 /**
 105  * Close the current playlist.
 106  *
 107  * \sa playlist_open().
 108  */
 109 void playlist_close(void)
 110 {
 111         free(playlist.name);
 112         playlist.name = NULL;
 113 }
 114
 115 /**
 116  * Open the given playlist.
 117  *
 118  * \param name The name of the playlist to open.
 119  *
 120  * If name is \p NULL, load the first available playlist. Files which are
 121  * listed in the playlist, but not contained in the database are ignored.
 122  * This is not considered an error.
 123  *
 124  * \return Positive on success, negative on errors. Possible errors
 125  * include: Given playlist not found, -E_NO_PLAYLIST (no playlist defined).
 126  */
 127 int playlist_open(char *name)
 128 {
 129         struct osl_object obj;
 130         int ret;
 131         struct osl_row *row;
 132
 133         if (!name)
 134                 return load_first_available_playlist();
 135         obj.data = name;
 136         obj.size = strlen(obj.data);
 137         ret = osl_get_row(playlists_table, BLOBCOL_NAME, &obj, &row);
 138         if (ret < 0) {
 139                 PARA_NOTICE_LOG("failed to load playlist %s\n", name);
 140                 return ret;
 141         }
 142         return load_playlist(row);
 143 }