| #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; |
| } |