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| | #ifndef PACK_OBJECTS_H
#define PACK_OBJECTS_H
#define OE_DFS_STATE_BITS 2
#define OE_DEPTH_BITS 12
#define OE_IN_PACK_BITS 12
#define IN_PACK_POS(to_pack, obj) \
(to_pack)->in_pack_pos[(struct object_entry *)(obj) - (to_pack)->objects]
#define IN_PACK(to_pack, obj) \
(to_pack)->in_pack[(obj)->in_pack_idx]
/*
* State flags for depth-first search used for analyzing delta cycles.
*
* The depth is measured in delta-links to the base (so if A is a delta
* against B, then A has a depth of 1, and B a depth of 0).
*/
enum dfs_state {
DFS_NONE = 0,
DFS_ACTIVE,
DFS_DONE,
DFS_NUM_STATES
};
/*
* The size of struct nearly determines pack-objects's memory
* consumption. This struct is packed tight for that reason. When you
* add or reorder something in this struct, think a bit about this.
*/
struct object_entry {
struct pack_idx_entry idx;
unsigned long size; /* uncompressed size */
off_t in_pack_offset;
uint32_t delta_idx; /* delta base object */
uint32_t delta_child_idx; /* deltified objects who bases me */
uint32_t delta_sibling_idx; /* other deltified objects who
* uses the same base as me
*/
uint32_t hash; /* name hint hash */
void *delta_data; /* cached delta (uncompressed) */
unsigned long delta_size; /* delta data size (uncompressed) */
unsigned long z_delta_size; /* delta data size (compressed) */
unsigned char in_pack_header_size; /* note: spare bits available! */
unsigned in_pack_idx:OE_IN_PACK_BITS; /* already in pack */
unsigned type:TYPE_BITS;
unsigned in_pack_type:TYPE_BITS; /* could be delta */
unsigned preferred_base:1; /*
* we do not pack this, but is available
* to be used as the base object to delta
* objects against.
*/
unsigned no_try_delta:1;
unsigned tagged:1; /* near the very tip of refs */
unsigned filled:1; /* assigned write-order */
unsigned dfs_state:OE_DFS_STATE_BITS;
/* XXX 8 bits hole, try to pack */
unsigned depth:OE_DEPTH_BITS;
/* size: 96 */
};
struct packing_data {
struct object_entry *objects;
uint32_t nr_objects, nr_alloc;
int32_t *index;
uint32_t index_size;
unsigned int *in_pack_pos;
struct packed_git *in_pack[1 << OE_IN_PACK_BITS];
};
struct object_entry *packlist_alloc(struct packing_data *pdata,
const unsigned char *sha1,
uint32_t index_pos);
struct object_entry *packlist_find(struct packing_data *pdata,
const unsigned char *sha1,
uint32_t *index_pos);
static inline uint32_t pack_name_hash(const char *name)
{
uint32_t c, hash = 0;
if (!name)
return 0;
/*
* This effectively just creates a sortable number from the
* last sixteen non-whitespace characters. Last characters
* count "most", so things that end in ".c" sort together.
*/
while ((c = *name++) != 0) {
if (isspace(c))
continue;
hash = (hash >> 2) + (c << 24);
}
return hash;
}
#endif
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