apps/tagdb/artist.h

   1 #ifndef __ARTIST_H__
   2 #define __ARTIST_H__
   3
   4 #include "config.h"
   5 #include <stdio.h>
   6 #include <stdint.h>
   7
   8 struct artist_entry {
   9         char* name;             // artist name
  10         uint32_t *album;        // album-pointers
  11         struct artist_size {
  12                 uint32_t name_len;      // length of this field (must be mulitple of 4)
  13                 uint32_t album_count;   // number of album pointers
  14         } size;
  15         unsigned char flag;             // flags
  16 };
  17
  18 struct artist_entry* new_artist_entry(const uint32_t name_len, const uint32_t album_count);
  19 /* Creates a new artist_entry with the specified sizes
  20  * Returns a pointer to the structure on success,
  21  * NULL on failure
  22 */
  23
  24 int artist_entry_destruct(struct artist_entry *e);
  25 /* Destructs the given artist_entry and free()'s it's memory
  26  * returns ERR_NONE on success (can't fail)
  27  */
  28
  29 int artist_entry_resize(struct artist_entry *e, const uint32_t name_len, const uint32_t album_count);
  30 /* Change the size of the entry
  31  * returns ERR_NONE on succes
  32  *         ERR_MALLOC on malloc() failure
  33  */
  34
  35 int artist_entry_serialize(FILE *fd, const struct artist_entry *e);
  36 /* Serializes the entry in the file at the current position
  37  * returns ERR_NONE on success
  38  *         ERR_FILE on fwrite() failure
  39  */
  40
  41 int artist_entry_unserialize(struct artist_entry* *e, FILE *fd);
  42 /* Unserializes an entry from file into a new structure
  43  * The address of the structure is saved into *e
  44  * returns ERR_NONE on success
  45  *         ERR_MALLOC on malloc() failure
  46  *         ERR_FILE on fread() failure
  47  */
  48
  49 int artist_entry_write(FILE *fd, const struct artist_entry *e, const struct artist_size *s);
  50 /* Writes the entry to file in the final form
  51  * returns ERR_NONE on success
  52  *         ERR_FILE on fwrite() failure
  53  */
  54
  55 inline int artist_entry_compare(const struct artist_entry *a, const struct artist_entry *b);
  56 /* Compares 2 entries
  57  * When a < b it returns <0
  58  *      a = b             0
  59  *      a > b            >0
  60  */
  61
  62 struct artist_size* new_artist_size();
  63 /* Creates a new size structure
  64  * returns a pointer to the structure on success,
  65  * NULL on failure
  66  */
  67
  68 inline uint32_t artist_size_get_length(const struct artist_size *size);
  69 /* Calculates the length of the entry when written by artist_entry_write()
  70  * returns the length on success (can't fail)
  71  */
  72
  73 inline int artist_size_max(struct artist_size *s, const struct artist_entry *e);
  74 /* Updates the artist_size structure to contain the maximal lengths of either
  75  * the original entry in s, or the entry e
  76  * returns ERR_NONE on success (can't fail)
  77  */
  78
  79 int artist_size_destruct(struct artist_size *s);
  80 /* destructs the artist_size structure
  81  * returns ERR_NONE on success (can't fail)
  82  */
  83
  84
  85 int artist_entry_add_album_mem(struct artist_entry *e, struct artist_size *s, const uint32_t album);
  86 /* Adds the album to the array
  87  * returns ERR_NONE on success
  88  *         ERR_MALLOC on malloc() failure
  89  */
  90
  91 int artist_entry_add_album_file(FILE *fd, struct artist_entry *e, struct artist_size *s, const uint32_t album);
  92 /* Adds the album to the serialized entry in the file
  93  * When this fails, the entry is invalidated and the function returns
  94  * ERR_NO_INPLACE_UPDATE
  95  * returns ERR_NONE on success
  96  *         ERR_NO_INPLACE_UPDATE (see above)
  97  *         ERR_FILE on fread()/fwrite() error
  98  */
  99
 100 #endif