object.hon commit Merge branch 'js/userdiff-cc' (c228a5c)
   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_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 */
  34struct 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
  42extern const char *typename(unsigned int type);
  43extern int type_from_string(const char *str);
  44
  45/*
  46 * Return the current number of buckets in the object hashmap.
  47 */
  48extern unsigned int get_max_object_index(void);
  49
  50/*
  51 * Return the object from the specified bucket in the object hashmap.
  52 */
  53extern 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 */
  67struct object *lookup_object(const unsigned char *sha1);
  68
  69extern 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 */
  76struct 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 */
  83struct 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 */
  89struct 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. **/
  92struct object *lookup_unknown_object(const unsigned  char *sha1);
  93
  94struct object_list *object_list_insert(struct object *item,
  95                                       struct object_list **list_p);
  96
  97int object_list_contains(struct object_list *list, struct object *obj);
  98
  99/* Object array handling .. */
 100void add_object_array(struct object *obj, const char *name, struct object_array *array);
 101void add_object_array_with_mode(struct object *obj, const char *name, struct object_array *array, unsigned mode);
 102void add_object_array_with_context(struct object *obj, const char *name, struct object_array *array, struct object_context *context);
 103
 104typedef 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 */
 111void 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 */
 118void object_array_remove_duplicates(struct object_array *array);
 119
 120void clear_object_flags(unsigned flags);
 121
 122#endif /* OBJECT_H */