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 /*
  30  * object flag allocation:
  31  * revision.h:      0---------10                                26
  32  * fetch-pack.c:    0---4
  33  * walker.c:        0-2
  34  * upload-pack.c:               11----------------19
  35  * builtin/blame.c:               12-13
  36  * bisect.c:                               16
  37  * bundle.c:                               16
  38  * http-push.c:                            16-----19
  39  * commit.c:                               16-----19
  40  * sha1_name.c:                                     20
  41  */
  42 #define FLAG_BITS  27
  43
  44 /*
  45  * The object type is stored in 3 bits.
  46  */
  47 struct object {
  48         unsigned parsed : 1;
  49         unsigned used : 1;
  50         unsigned type : TYPE_BITS;
  51         unsigned flags : FLAG_BITS;
  52         unsigned char sha1[20];
  53 };
  54
  55 extern const char *typename(unsigned int type);
  56 extern int type_from_string(const char *str);
  57
  58 /*
  59  * Return the current number of buckets in the object hashmap.
  60  */
  61 extern unsigned int get_max_object_index(void);
  62
  63 /*
  64  * Return the object from the specified bucket in the object hashmap.
  65  */
  66 extern struct object *get_indexed_object(unsigned int);
  67
  68 /*
  69  * This can be used to see if we have heard of the object before, but
  70  * it can return "yes we have, and here is a half-initialised object"
  71  * for an object that we haven't loaded/parsed yet.
  72  *
  73  * When parsing a commit to create an in-core commit object, its
  74  * parents list holds commit objects that represent its parents, but
  75  * they are expected to be lazily initialized and do not know what
  76  * their trees or parents are yet.  When this function returns such a
  77  * half-initialised objects, the caller is expected to initialize them
  78  * by calling parse_object() on them.
  79  */
  80 struct object *lookup_object(const unsigned char *sha1);
  81
  82 extern void *create_object(const unsigned char *sha1, int type, void *obj);
  83
  84 /*
  85  * Returns the object, having parsed it to find out what it is.
  86  *
  87  * Returns NULL if the object is missing or corrupt.
  88  */
  89 struct object *parse_object(const unsigned char *sha1);
  90
  91 /*
  92  * Like parse_object, but will die() instead of returning NULL. If the
  93  * "name" parameter is not NULL, it is included in the error message
  94  * (otherwise, the sha1 hex is given).
  95  */
  96 struct object *parse_object_or_die(const unsigned char *sha1, const char *name);
  97
  98 /* Given the result of read_sha1_file(), returns the object after
  99  * parsing it.  eaten_p indicates if the object has a borrowed copy
 100  * of buffer and the caller should not free() it.
 101  */
 102 struct object *parse_object_buffer(const unsigned char *sha1, enum object_type type, unsigned long size, void *buffer, int *eaten_p);
 103
 104 /** Returns the object, with potentially excess memory allocated. **/
 105 struct object *lookup_unknown_object(const unsigned  char *sha1);
 106
 107 struct object_list *object_list_insert(struct object *item,
 108                                        struct object_list **list_p);
 109
 110 int object_list_contains(struct object_list *list, struct object *obj);
 111
 112 /* Object array handling .. */
 113 void add_object_array(struct object *obj, const char *name, struct object_array *array);
 114 void add_object_array_with_mode(struct object *obj, const char *name, struct object_array *array, unsigned mode);
 115 void add_object_array_with_context(struct object *obj, const char *name, struct object_array *array, struct object_context *context);
 116
 117 typedef int (*object_array_each_func_t)(struct object_array_entry *, void *);
 118
 119 /*
 120  * Apply want to each entry in array, retaining only the entries for
 121  * which the function returns true.  Preserve the order of the entries
 122  * that are retained.
 123  */
 124 void object_array_filter(struct object_array *array,
 125                          object_array_each_func_t want, void *cb_data);
 126
 127 /*
 128  * Remove from array all but the first entry with a given name.
 129  * Warning: this function uses an O(N^2) algorithm.
 130  */
 131 void object_array_remove_duplicates(struct object_array *array);
 132
 133 void clear_object_flags(unsigned flags);
 134
 135 #endif /* OBJECT_H */