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Merge branch 'ds/bsearch-hash'

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Code to find the length to uniquely abbreviate object names based
on packfile content, which is a relatively recent addtion, has been
optimized to use the same fan-out table.

* ds/bsearch-hash:
  sha1_name: use bsearch_pack() in unique_in_pack()
  sha1_name: use bsearch_pack() for abbreviations
  packfile: define and use bsearch_pack()
  sha1_name: convert struct min_abbrev_data to object_id
This commit is contained in:
Junio C Hamano 2018-04-10 16:28:22 +09:00
commit 51f813c6b3
3 changed files with 42 additions and 57 deletions
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42
packfile.c
View File

@ -1654,6 +1654,29 @@ out:
return data;
}
int bsearch_pack(const struct object_id *oid, const struct packed_git *p, uint32_t *result)
{
const unsigned char *index_fanout = p->index_data;
const unsigned char *index_lookup;
int index_lookup_width;
if (!index_fanout)
BUG("bsearch_pack called without a valid pack-index");
index_lookup = index_fanout + 4 * 256;
if (p->index_version == 1) {
index_lookup_width = 24;
index_lookup += 4;
} else {
index_lookup_width = 20;
index_fanout += 8;
index_lookup += 8;
}
return bsearch_hash(oid->hash, (const uint32_t*)index_fanout,
index_lookup, index_lookup_width, result);
}
const unsigned char *nth_packed_object_sha1(struct packed_git *p,
uint32_t n)
{
@ -1720,30 +1743,17 @@ off_t nth_packed_object_offset(const struct packed_git *p, uint32_t n)
off_t find_pack_entry_one(const unsigned char *sha1,
struct packed_git *p)
{
const uint32_t *level1_ofs = p->index_data;
const unsigned char *index = p->index_data;
unsigned stride;
struct object_id oid;
uint32_t result;
if (!index) {
if (open_pack_index(p))
return 0;
level1_ofs = p->index_data;
index = p->index_data;
}
if (p->index_version > 1) {
level1_ofs += 2;
index += 8;
}
index += 4 * 256;
if (p->index_version > 1) {
stride = 20;
} else {
stride = 24;
index += 4;
}
if (bsearch_hash(sha1, level1_ofs, index, stride, &result))
hashcpy(oid.hash, sha1);
if (bsearch_pack(&oid, p, &result))
return nth_packed_object_offset(p, result);
return 0;
}

8
packfile.h
View File

@ -78,6 +78,14 @@ extern struct packed_git *add_packed_git(const char *path, size_t path_len, int
*/
extern void check_pack_index_ptr(const struct packed_git *p, const void *ptr);
/*
* Perform binary search on a pack-index for a given oid. Packfile is expected to
* have a valid pack-index.
*
* See 'bsearch_hash' for more information.
*/
int bsearch_pack(const struct object_id *oid, const struct packed_git *p, uint32_t *result);
/*
* Return the SHA-1 of the nth object within the specified packfile.
* Open the index if it is not already open. The return value points

49
sha1_name.c
View File

@ -150,31 +150,14 @@ static int match_sha(unsigned len, const unsigned char *a, const unsigned char *
static void unique_in_pack(struct packed_git *p,
struct disambiguate_state *ds)
{
uint32_t num, last, i, first = 0;
uint32_t num, i, first = 0;
const struct object_id *current = NULL;
if (open_pack_index(p) || !p->num_objects)
return;
num = p->num_objects;
last = num;
while (first < last) {
uint32_t mid = first + (last - first) / 2;
const unsigned char *current;
int cmp;
current = nth_packed_object_sha1(p, mid);
cmp = hashcmp(ds->bin_pfx.hash, current);
if (!cmp) {
first = mid;
break;
}
if (cmp > 0) {
first = mid+1;
continue;
}
last = mid;
}
bsearch_pack(&ds->bin_pfx, p, &first);
/*
* At this point, "first" is the location of the lowest object
@ -480,7 +463,7 @@ struct min_abbrev_data {
unsigned int init_len;
unsigned int cur_len;
char *hex;
const unsigned char *hash;
const struct object_id *oid;
};
static inline char get_hex_char_from_oid(const struct object_id *oid,
@ -512,32 +495,16 @@ static void find_abbrev_len_for_pack(struct packed_git *p,
struct min_abbrev_data *mad)
{
int match = 0;
uint32_t num, last, first = 0;
uint32_t num, first = 0;
struct object_id oid;
const struct object_id *mad_oid;
if (open_pack_index(p) || !p->num_objects)
return;
num = p->num_objects;
last = num;
while (first < last) {
uint32_t mid = first + (last - first) / 2;
const unsigned char *current;
int cmp;
current = nth_packed_object_sha1(p, mid);
cmp = hashcmp(mad->hash, current);
if (!cmp) {
match = 1;
first = mid;
break;
}
if (cmp > 0) {
first = mid + 1;
continue;
}
last = mid;
}
mad_oid = mad->oid;
match = bsearch_pack(mad_oid, p, &first);
/*
* first is now the position in the packfile where we would insert
@ -603,7 +570,7 @@ int find_unique_abbrev_r(char *hex, const struct object_id *oid, int len)
mad.init_len = len;
mad.cur_len = len;
mad.hex = hex;
mad.hash = oid->hash;
mad.oid = oid;
find_abbrev_len_packed(&mad);