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#include "cache.h"
#include "object.h"
#include "pack.h"
#include "pack-objects.h"
static uint32_t locate_object_entry_hash(struct packing_data *pdata,
const unsigned char *sha1,
int *found)
{
uint32_t i, hash, mask = (pdata->index_size - 1);
memcpy(&hash, sha1, sizeof(uint32_t));
i = hash & mask;
while (pdata->index[i] > 0) {
uint32_t pos = pdata->index[i] - 1;
if (!hashcmp(sha1, pdata->objects[pos].idx.sha1)) {
*found = 1;
return i;
}
i = (i + 1) & mask;
}
*found = 0;
return i;
}
static inline uint32_t closest_pow2(uint32_t v)
{
v = v - 1;
v |= v >> 1;
v |= v >> 2;
v |= v >> 4;
v |= v >> 8;
v |= v >> 16;
return v + 1;
}
static void rehash_objects(struct packing_data *pdata)
{
uint32_t i;
struct object_entry *entry;
pdata->index_size = closest_pow2(pdata->nr_objects * 3);
if (pdata->index_size < 1024)
pdata->index_size = 1024;
pdata->index = xrealloc(pdata->index, sizeof(uint32_t) * pdata->index_size);
memset(pdata->index, 0, sizeof(int) * pdata->index_size);
entry = pdata->objects;
for (i = 0; i < pdata->nr_objects; i++) {
int found;
uint32_t ix = locate_object_entry_hash(pdata, entry->idx.sha1, &found);
if (found)
die("BUG: Duplicate object in hash");
pdata->index[ix] = i + 1;
entry++;
}
}
struct object_entry *packlist_find(struct packing_data *pdata,
const unsigned char *sha1,
uint32_t *index_pos)
{
uint32_t i;
int found;
if (!pdata->index_size)
return NULL;
i = locate_object_entry_hash(pdata, sha1, &found);
if (index_pos)
*index_pos = i;
if (!found)
return NULL;
return &pdata->objects[pdata->index[i] - 1];
}
struct object_entry *packlist_alloc(struct packing_data *pdata,
const unsigned char *sha1,
uint32_t index_pos)
{
struct object_entry *new_entry;
if (pdata->nr_objects >= pdata->nr_alloc) {
pdata->nr_alloc = (pdata->nr_alloc + 1024) * 3 / 2;
pdata->objects = xrealloc(pdata->objects,
pdata->nr_alloc * sizeof(*new_entry));
}
new_entry = pdata->objects + pdata->nr_objects++;
memset(new_entry, 0, sizeof(*new_entry));
hashcpy(new_entry->idx.sha1, sha1);
if (pdata->index_size * 3 <= pdata->nr_objects * 4)
rehash_objects(pdata);
else
pdata->index[index_pos] = pdata->nr_objects;
return new_entry;
}
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