From 9cb76b8cdc8ac62a77080595f6443613fd64bab3 Mon Sep 17 00:00:00 2001 From: Junio C Hamano Date: Tue, 22 Jan 2008 23:01:13 -0800 Subject: [PATCH] lazy index hashing This delays the hashing of index names until it becomes necessary for the first time. Signed-off-by: Junio C Hamano --- cache.h | 1 + read-cache.c | 26 +++++++++++++++++++++++--- 2 files changed, 24 insertions(+), 3 deletions(-) diff --git a/cache.h b/cache.h index 409738ca6..e4aeff07d 100644 --- a/cache.h +++ b/cache.h @@ -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; }; diff --git a/read-cache.c b/read-cache.c index 9477c0b39..e45f4b3d6 100644 --- a/read-cache.c +++ b/read-cache.c @@ -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)) { -- 2.30.2