pack-objects.h

   1 #ifndef PACK_OBJECTS_H
   2 #define PACK_OBJECTS_H
   3
   4 #define DEFAULT_DELTA_CACHE_SIZE (256 * 1024 * 1024)
   5
   6 struct object_entry {
   7         struct pack_idx_entry idx;
   8         unsigned long size;     /* uncompressed size */
   9         struct packed_git *in_pack;     /* already in pack */
  10         off_t in_pack_offset;
  11         struct object_entry *delta;     /* delta base object */
  12         struct object_entry *delta_child; /* deltified objects who bases me */
  13         struct object_entry *delta_sibling; /* other deltified objects who
  14                                              * uses the same base as me
  15                                              */
  16         void *delta_data;       /* cached delta (uncompressed) */
  17         unsigned long delta_size;       /* delta data size (uncompressed) */
  18         unsigned long z_delta_size;     /* delta data size (compressed) */
  19         enum object_type type;
  20         enum object_type in_pack_type;  /* could be delta */
  21         uint32_t hash;                  /* name hint hash */
  22         unsigned int in_pack_pos;
  23         unsigned char in_pack_header_size;
  24         unsigned preferred_base:1; /*
  25                                     * we do not pack this, but is available
  26                                     * to be used as the base object to delta
  27                                     * objects against.
  28                                     */
  29         unsigned no_try_delta:1;
  30         unsigned tagged:1; /* near the very tip of refs */
  31         unsigned filled:1; /* assigned write-order */
  32
  33         /*
  34          * State flags for depth-first search used for analyzing delta cycles.
  35          *
  36          * The depth is measured in delta-links to the base (so if A is a delta
  37          * against B, then A has a depth of 1, and B a depth of 0).
  38          */
  39         enum {
  40                 DFS_NONE = 0,
  41                 DFS_ACTIVE,
  42                 DFS_DONE
  43         } dfs_state;
  44         int depth;
  45 };
  46
  47 struct packing_data {
  48         struct object_entry *objects;
  49         uint32_t nr_objects, nr_alloc;
  50
  51         int32_t *index;
  52         uint32_t index_size;
  53 };
  54
  55 struct object_entry *packlist_alloc(struct packing_data *pdata,
  56                                     const unsigned char *sha1,
  57                                     uint32_t index_pos);
  58
  59 struct object_entry *packlist_find(struct packing_data *pdata,
  60                                    const unsigned char *sha1,
  61                                    uint32_t *index_pos);
  62
  63 static inline uint32_t pack_name_hash(const char *name)
  64 {
  65         uint32_t c, hash = 0;
  66
  67         if (!name)
  68                 return 0;
  69
  70         /*
  71          * This effectively just creates a sortable number from the
  72          * last sixteen non-whitespace characters. Last characters
  73          * count "most", so things that end in ".c" sort together.
  74          */
  75         while ((c = *name++) != 0) {
  76                 if (isspace(c))
  77                         continue;
  78                 hash = (hash >> 2) + (c << 24);
  79         }
  80         return hash;
  81 }
  82
  83 #endif