diff options
Diffstat (limited to 'name-hash.c')
-rw-r--r-- | name-hash.c | 163 |
1 files changed, 53 insertions, 110 deletions
diff --git a/name-hash.c b/name-hash.c index e5b6e1ad2..97444d020 100644 --- a/name-hash.c +++ b/name-hash.c @@ -8,49 +8,28 @@ #define NO_THE_INDEX_COMPATIBILITY_MACROS #include "cache.h" -/* - * This removes bit 5 if bit 6 is set. - * - * That will make US-ASCII characters hash to their upper-case - * equivalent. We could easily do this one whole word at a time, - * but that's for future worries. - */ -static inline unsigned char icase_hash(unsigned char c) -{ - return c & ~((c & 0x40) >> 1); -} - -static unsigned int hash_name(const char *name, int namelen) -{ - unsigned int hash = 0x123; - - while (namelen--) { - unsigned char c = *name++; - c = icase_hash(c); - hash = hash*101 + c; - } - return hash; -} - struct dir_entry { - struct dir_entry *next; + struct hashmap_entry ent; struct dir_entry *parent; struct cache_entry *ce; int nr; unsigned int namelen; }; +static int dir_entry_cmp(const struct dir_entry *e1, + const struct dir_entry *e2, const char *name) +{ + return e1->namelen != e2->namelen || strncasecmp(e1->ce->name, + name ? name : e2->ce->name, e1->namelen); +} + static struct dir_entry *find_dir_entry(struct index_state *istate, const char *name, unsigned int namelen) { - unsigned int hash = hash_name(name, namelen); - struct dir_entry *dir; - - for (dir = lookup_hash(hash, &istate->dir_hash); dir; dir = dir->next) - if (dir->namelen == namelen && - !strncasecmp(dir->ce->name, name, namelen)) - return dir; - return NULL; + struct dir_entry key; + hashmap_entry_init(&key, memihash(name, namelen)); + key.namelen = namelen; + return hashmap_get(&istate->dir_hash, &key, name); } static struct dir_entry *hash_dir_entry(struct index_state *istate, @@ -84,18 +63,11 @@ static struct dir_entry *hash_dir_entry(struct index_state *istate, dir = find_dir_entry(istate, ce->name, namelen); if (!dir) { /* not found, create it and add to hash table */ - void **pdir; - unsigned int hash = hash_name(ce->name, namelen); - dir = xcalloc(1, sizeof(struct dir_entry)); + hashmap_entry_init(dir, memihash(ce->name, namelen)); dir->namelen = namelen; dir->ce = ce; - - pdir = insert_hash(hash, dir, &istate->dir_hash); - if (pdir) { - dir->next = *pdir; - *pdir = dir; - } + hashmap_add(&istate->dir_hash, dir); /* recursively add missing parent directories */ dir->parent = hash_dir_entry(istate, ce, namelen); @@ -114,45 +86,50 @@ static void add_dir_entry(struct index_state *istate, struct cache_entry *ce) static void remove_dir_entry(struct index_state *istate, struct cache_entry *ce) { /* - * Release reference to the directory entry (and parents if 0). - * - * Note: we do not remove / free the entry because there's no - * hash.[ch]::remove_hash and dir->next may point to other entries - * that are still valid, so we must not free the memory. + * Release reference to the directory entry. If 0, remove and continue + * with parent directory. */ struct dir_entry *dir = hash_dir_entry(istate, ce, ce_namelen(ce)); - while (dir && dir->nr && !(--dir->nr)) - dir = dir->parent; + while (dir && !(--dir->nr)) { + struct dir_entry *parent = dir->parent; + hashmap_remove(&istate->dir_hash, dir, NULL); + free(dir); + dir = parent; + } } static void hash_index_entry(struct index_state *istate, struct cache_entry *ce) { - void **pos; - unsigned int hash; - if (ce->ce_flags & CE_HASHED) return; ce->ce_flags |= CE_HASHED; - ce->next = NULL; - hash = hash_name(ce->name, ce_namelen(ce)); - pos = insert_hash(hash, ce, &istate->name_hash); - if (pos) { - ce->next = *pos; - *pos = ce; - } + hashmap_entry_init(ce, memihash(ce->name, ce_namelen(ce))); + hashmap_add(&istate->name_hash, ce); - if (ignore_case && !(ce->ce_flags & CE_UNHASHED)) + if (ignore_case) add_dir_entry(istate, ce); } +static int cache_entry_cmp(const struct cache_entry *ce1, + const struct cache_entry *ce2, const void *remove) +{ + /* + * For remove_name_hash, find the exact entry (pointer equality); for + * index_file_exists, find all entries with matching hash code and + * decide whether the entry matches in same_name. + */ + return remove ? !(ce1 == ce2) : 0; +} + static void lazy_init_name_hash(struct index_state *istate) { int nr; if (istate->name_hash_initialized) return; - if (istate->cache_nr) - preallocate_hash(&istate->name_hash, istate->cache_nr); + hashmap_init(&istate->name_hash, (hashmap_cmp_fn) cache_entry_cmp, + istate->cache_nr); + hashmap_init(&istate->dir_hash, (hashmap_cmp_fn) dir_entry_cmp, 0); for (nr = 0; nr < istate->cache_nr; nr++) hash_index_entry(istate, istate->cache[nr]); istate->name_hash_initialized = 1; @@ -160,31 +137,19 @@ static void lazy_init_name_hash(struct index_state *istate) void add_name_hash(struct index_state *istate, struct cache_entry *ce) { - /* if already hashed, add reference to directory entries */ - if (ignore_case && (ce->ce_flags & CE_STATE_MASK) == CE_STATE_MASK) - add_dir_entry(istate, ce); - - ce->ce_flags &= ~CE_UNHASHED; if (istate->name_hash_initialized) hash_index_entry(istate, ce); } -/* - * We don't actually *remove* it, we can just mark it invalid so that - * we won't find it in lookups. - * - * Not only would we have to search the lists (simple enough), but - * we'd also have to rehash other hash buckets in case this makes the - * hash bucket empty (common). So it's much better to just mark - * it. - */ void remove_name_hash(struct index_state *istate, struct cache_entry *ce) { - /* if already hashed, release reference to directory entries */ - if (ignore_case && (ce->ce_flags & CE_STATE_MASK) == CE_HASHED) - remove_dir_entry(istate, ce); + if (!istate->name_hash_initialized || !(ce->ce_flags & CE_HASHED)) + return; + ce->ce_flags &= ~CE_HASHED; + hashmap_remove(&istate->name_hash, ce, ce); - ce->ce_flags |= CE_UNHASHED; + if (ignore_case) + remove_dir_entry(istate, ce); } static int slow_same_name(const char *name1, int len1, const char *name2, int len2) @@ -247,49 +212,27 @@ struct cache_entry *index_dir_exists(struct index_state *istate, const char *nam struct cache_entry *index_file_exists(struct index_state *istate, const char *name, int namelen, int icase) { - unsigned int hash = hash_name(name, namelen); struct cache_entry *ce; + struct hashmap_entry key; lazy_init_name_hash(istate); - ce = lookup_hash(hash, &istate->name_hash); + hashmap_entry_init(&key, memihash(name, namelen)); + ce = hashmap_get(&istate->name_hash, &key, NULL); while (ce) { - if (!(ce->ce_flags & CE_UNHASHED)) { - if (same_name(ce, name, namelen, icase)) - return ce; - } - ce = ce->next; + if (same_name(ce, name, namelen, icase)) + return ce; + ce = hashmap_get_next(&istate->name_hash, ce); } return NULL; } -struct cache_entry *index_name_exists(struct index_state *istate, const char *name, int namelen, int icase) -{ - if (namelen > 0 && name[namelen - 1] == '/') - return index_dir_exists(istate, name, namelen - 1); - return index_file_exists(istate, name, namelen, icase); -} - -static int free_dir_entry(void *entry, void *unused) -{ - struct dir_entry *dir = entry; - while (dir) { - struct dir_entry *next = dir->next; - free(dir); - dir = next; - } - return 0; -} - void free_name_hash(struct index_state *istate) { if (!istate->name_hash_initialized) return; istate->name_hash_initialized = 0; - if (ignore_case) - /* free directory entries */ - for_each_hash(&istate->dir_hash, free_dir_entry, NULL); - free_hash(&istate->name_hash); - free_hash(&istate->dir_hash); + hashmap_free(&istate->name_hash, 0); + hashmap_free(&istate->dir_hash, 1); } |