object.h

   1 #ifndef OBJECT_H
   2 #define OBJECT_H
   3
   4 struct object_list {
   5         struct object *item;
   6         struct object_list *next;
   7 };
   8
   9 struct object_array {
  10         unsigned int nr;
  11         unsigned int alloc;
  12         struct object_array_entry {
  13                 struct object *item;
  14                 /*
  15                  * name or NULL.  If non-NULL, the memory pointed to
  16                  * is owned by this object *except* if it points at
  17                  * object_array_slopbuf, which is a static copy of the
  18                  * empty string.
  19                  */
  20                 char *name;
  21                 unsigned mode;
  22                 struct object_context *context;
  23         } *objects;
  24 };
  25
  26 #define OBJECT_ARRAY_INIT { 0, 0, NULL }
  27
  28 #define TYPE_BITS   3
  29 #define FLAG_BITS  27
  30
  31 /*
  32  * The object type is stored in 3 bits.
  33  */
  34 struct object {
  35         unsigned parsed : 1;
  36         unsigned used : 1;
  37         unsigned type : TYPE_BITS;
  38         unsigned flags : FLAG_BITS;
  39         unsigned char sha1[20];
  40 };
  41
  42 extern const char *typename(unsigned int type);
  43 extern int type_from_string(const char *str);
  44
  45 /*
  46  * Return the current number of buckets in the object hashmap.
  47  */
  48 extern unsigned int get_max_object_index(void);
  49
  50 /*
  51  * Return the object from the specified bucket in the object hashmap.
  52  */
  53 extern struct object *get_indexed_object(unsigned int);
  54
  55 /*
  56  * This can be used to see if we have heard of the object before, but
  57  * it can return "yes we have, and here is a half-initialised object"
  58  * for an object that we haven't loaded/parsed yet.
  59  *
  60  * When parsing a commit to create an in-core commit object, its
  61  * parents list holds commit objects that represent its parents, but
  62  * they are expected to be lazily initialized and do not know what
  63  * their trees or parents are yet.  When this function returns such a
  64  * half-initialised objects, the caller is expected to initialize them
  65  * by calling parse_object() on them.
  66  */
  67 struct object *lookup_object(const unsigned char *sha1);
  68
  69 extern void *create_object(const unsigned char *sha1, int type, void *obj);
  70
  71 /*
  72  * Returns the object, having parsed it to find out what it is.
  73  *
  74  * Returns NULL if the object is missing or corrupt.
  75  */
  76 struct object *parse_object(const unsigned char *sha1);
  77
  78 /*
  79  * Like parse_object, but will die() instead of returning NULL. If the
  80  * "name" parameter is not NULL, it is included in the error message
  81  * (otherwise, the sha1 hex is given).
  82  */
  83 struct object *parse_object_or_die(const unsigned char *sha1, const char *name);
  84
  85 /* Given the result of read_sha1_file(), returns the object after
  86  * parsing it.  eaten_p indicates if the object has a borrowed copy
  87  * of buffer and the caller should not free() it.
  88  */
  89 struct object *parse_object_buffer(const unsigned char *sha1, enum object_type type, unsigned long size, void *buffer, int *eaten_p);
  90
  91 /** Returns the object, with potentially excess memory allocated. **/
  92 struct object *lookup_unknown_object(const unsigned  char *sha1);
  93
  94 struct object_list *object_list_insert(struct object *item,
  95                                        struct object_list **list_p);
  96
  97 int object_list_contains(struct object_list *list, struct object *obj);
  98
  99 /* Object array handling .. */
 100 void add_object_array(struct object *obj, const char *name, struct object_array *array);
 101 void add_object_array_with_mode(struct object *obj, const char *name, struct object_array *array, unsigned mode);
 102 void add_object_array_with_context(struct object *obj, const char *name, struct object_array *array, struct object_context *context);
 103
 104 typedef int (*object_array_each_func_t)(struct object_array_entry *, void *);
 105
 106 /*
 107  * Apply want to each entry in array, retaining only the entries for
 108  * which the function returns true.  Preserve the order of the entries
 109  * that are retained.
 110  */
 111 void object_array_filter(struct object_array *array,
 112                          object_array_each_func_t want, void *cb_data);
 113
 114 /*
 115  * Remove from array all but the first entry with a given name.
 116  * Warning: this function uses an O(N^2) algorithm.
 117  */
 118 void object_array_remove_duplicates(struct object_array *array);
 119
 120 void clear_object_flags(unsigned flags);
 121
 122 #endif /* OBJECT_H */