object.hon commit revision.c: explain what tree_difference does (0a4ba7f)
   1#ifndef OBJECT_H
   2#define OBJECT_H
   3
   4struct object_list {
   5        struct object *item;
   6        struct object_list *next;
   7};
   8
   9struct object_refs {
  10        unsigned count;
  11        struct object *base;
  12        struct object *ref[FLEX_ARRAY]; /* more */
  13};
  14
  15struct object_array {
  16        unsigned int nr;
  17        unsigned int alloc;
  18        struct object_array_entry {
  19                struct object *item;
  20                const char *name;
  21        } *objects;
  22};
  23
  24#define TYPE_BITS   3
  25#define FLAG_BITS  27
  26
  27/*
  28 * The object type is stored in 3 bits.
  29 */
  30struct object {
  31        unsigned parsed : 1;
  32        unsigned used : 1;
  33        unsigned type : TYPE_BITS;
  34        unsigned flags : FLAG_BITS;
  35        unsigned char sha1[20];
  36};
  37
  38extern int track_object_refs;
  39
  40extern const char *typename(unsigned int type);
  41extern int type_from_string(const char *str);
  42
  43extern unsigned int get_max_object_index(void);
  44extern struct object *get_indexed_object(unsigned int);
  45extern struct object_refs *lookup_object_refs(struct object *);
  46
  47/** Internal only **/
  48struct object *lookup_object(const unsigned char *sha1);
  49
  50void created_object(const unsigned char *sha1, struct object *obj);
  51
  52/** Returns the object, having parsed it to find out what it is. **/
  53struct object *parse_object(const unsigned char *sha1);
  54
  55/* Given the result of read_sha1_file(), returns the object after
  56 * parsing it.  eaten_p indicates if the object has a borrowed copy
  57 * of buffer and the caller should not free() it.
  58 */
  59struct object *parse_object_buffer(const unsigned char *sha1, enum object_type type, unsigned long size, void *buffer, int *eaten_p);
  60
  61/** Returns the object, with potentially excess memory allocated. **/
  62struct object *lookup_unknown_object(const unsigned  char *sha1);
  63
  64struct object_refs *alloc_object_refs(unsigned count);
  65void set_object_refs(struct object *obj, struct object_refs *refs);
  66
  67void mark_reachable(struct object *obj, unsigned int mask);
  68
  69struct object_list *object_list_insert(struct object *item, 
  70                                       struct object_list **list_p);
  71
  72void object_list_append(struct object *item,
  73                        struct object_list **list_p);
  74
  75unsigned object_list_length(struct object_list *list);
  76
  77int object_list_contains(struct object_list *list, struct object *obj);
  78
  79/* Object array handling .. */
  80void add_object_array(struct object *obj, const char *name, struct object_array *array);
  81
  82#endif /* OBJECT_H */