mirror of
https://github.com/git/git.git
synced 2024-11-15 14:14:08 +01:00
b4e00f7306
Subsequent patches will introduce file formats that make use of a fanout array and a sorted table containing hashes, just like packfiles. Refactor the hash search in packfile.c into its own function, so that those patches can make use of it as well. Signed-off-by: Jonathan Tan <jonathantanmy@google.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
33 lines
1.3 KiB
C
33 lines
1.3 KiB
C
#ifndef SHA1_LOOKUP_H
|
|
#define SHA1_LOOKUP_H
|
|
|
|
typedef const unsigned char *sha1_access_fn(size_t index, void *table);
|
|
|
|
extern int sha1_pos(const unsigned char *sha1,
|
|
void *table,
|
|
size_t nr,
|
|
sha1_access_fn fn);
|
|
|
|
/*
|
|
* Searches for sha1 in table, using the given fanout table to determine the
|
|
* interval to search, then using binary search. Returns 1 if found, 0 if not.
|
|
*
|
|
* Takes the following parameters:
|
|
*
|
|
* - sha1: the hash to search for
|
|
* - fanout_nbo: a 256-element array of NETWORK-order 32-bit integers; the
|
|
* integer at position i represents the number of elements in table whose
|
|
* first byte is less than or equal to i
|
|
* - table: a sorted list of hashes with optional extra information in between
|
|
* - stride: distance between two consecutive elements in table (should be
|
|
* GIT_MAX_RAWSZ or greater)
|
|
* - result: if not NULL, this function stores the element index of the
|
|
* position found (if the search is successful) or the index of the least
|
|
* element that is greater than sha1 (if the search is not successful)
|
|
*
|
|
* This function does not verify the validity of the fanout table.
|
|
*/
|
|
int bsearch_hash(const unsigned char *sha1, const uint32_t *fanout_nbo,
|
|
const unsigned char *table, size_t stride, uint32_t *result);
|
|
#endif
|