lazy index hashing

This delays the hashing of index names until it becomes necessary for
the first time.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Junio C Hamano 2008-01-22 23:01:13 -08:00
parent cf558704fb
commit 9cb76b8cdc
2 changed files with 24 additions and 3 deletions

View File

@ -191,6 +191,7 @@ struct index_state {
struct cache_tree *cache_tree;
time_t timestamp;
void *alloc;
unsigned name_hash_initialized : 1;
struct hash_table name_hash;
};

View File

@ -34,12 +34,11 @@ static unsigned int hash_name(const char *name, int namelen)
return hash;
}
static void set_index_entry(struct index_state *istate, int nr, struct cache_entry *ce)
static void hash_index_entry(struct index_state *istate, struct cache_entry *ce)
{
void **pos;
unsigned int hash = hash_name(ce->name, ce_namelen(ce));
istate->cache[nr] = ce;
pos = insert_hash(hash, ce, &istate->name_hash);
if (pos) {
ce->next = *pos;
@ -47,6 +46,24 @@ static void set_index_entry(struct index_state *istate, int nr, struct cache_ent
}
}
static void lazy_init_name_hash(struct index_state *istate)
{
int nr;
if (istate->name_hash_initialized)
return;
for (nr = 0; nr < istate->cache_nr; nr++)
hash_index_entry(istate, istate->cache[nr]);
istate->name_hash_initialized = 1;
}
static void set_index_entry(struct index_state *istate, int nr, struct cache_entry *ce)
{
istate->cache[nr] = ce;
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.
@ -75,7 +92,10 @@ static void replace_index_entry(struct index_state *istate, int nr, struct cache
int index_name_exists(struct index_state *istate, const char *name, int namelen)
{
unsigned int hash = hash_name(name, namelen);
struct cache_entry *ce = lookup_hash(hash, &istate->name_hash);
struct cache_entry *ce;
lazy_init_name_hash(istate);
ce = lookup_hash(hash, &istate->name_hash);
while (ce) {
if (!(ce->ce_flags & CE_UNHASHED)) {