X-Git-Url: https://git.ozlabs.org/?a=blobdiff_plain;f=ccan%2Fhtable%2Fhtable.h;h=03193567d847a5512b31d173bcb8a21a6d54d09e;hb=4ad5144790a12523f8a7c24c469a34907b6942a6;hp=b3962ac050251747706c3de25259b781e3b026ca;hpb=0c3590dc33d644f73bb8587db454c491830aaf26;p=ccan diff --git a/ccan/htable/htable.h b/ccan/htable/htable.h index b3962ac0..03193567 100644 --- a/ccan/htable/htable.h +++ b/ccan/htable/htable.h @@ -24,7 +24,26 @@ struct htable { }; /** - * htable_init - initialize an empty hash tree. + * HTABLE_INITIALIZER - static initialization for a hash table. + * @name: name of this htable. + * @rehash: hash function to use for rehashing. + * @priv: private argument to @rehash function. + * + * This is useful for setting up static and global hash tables. + * + * Example: + * // For simplicity's sake, say hash value is contents of elem. + * static size_t rehash(const void *elem, void *unused) + * { + * return *(size_t *)elem; + * } + * static struct htable ht = HTABLE_INITIALIZER(ht, rehash, NULL); + */ +#define HTABLE_INITIALIZER(name, rehash, priv) \ + { rehash, priv, 0, 0, 0, 0, 0, -1, 0, 0, &name.perfect_bit } + +/** + * htable_init - initialize an empty hash table. * @ht: the hash table to initialize * @rehash: hash function to use for rehashing. * @priv: private argument to @rehash function. @@ -33,7 +52,22 @@ void htable_init(struct htable *ht, size_t (*rehash)(const void *elem, void *priv), void *priv); /** - * htable_clear - empty a hash tree. + * htable_init_sized - initialize an empty hash table of given size. + * @ht: the hash table to initialize + * @rehash: hash function to use for rehashing. + * @priv: private argument to @rehash function. + * @size: the number of element. + * + * If this returns false, @ht is still usable, but may need to do reallocation + * upon an add. If this returns true, it will not need to reallocate within + * @size htable_adds. + */ +bool htable_init_sized(struct htable *ht, + size_t (*rehash)(const void *elem, void *priv), + void *priv, size_t size); + +/** + * htable_clear - empty a hash table. * @ht: the hash table to clear * * This doesn't do anything to any pointers left in it. @@ -48,7 +82,7 @@ void htable_clear(struct htable *ht); size_t htable_rehash(const void *elem); /** - * htable_add - add a pointer into a hash tree. + * htable_add - add a pointer into a hash table. * @ht: the htable * @hash: the hash value of the object * @p: the non-NULL pointer @@ -59,7 +93,7 @@ size_t htable_rehash(const void *elem); bool htable_add(struct htable *ht, size_t hash, const void *p); /** - * htable_del - remove a pointer from a hash tree + * htable_del - remove a pointer from a hash table * @ht: the htable * @hash: the hash value of the object * @p: the pointer @@ -145,7 +179,7 @@ void *htable_first(const struct htable *htable, struct htable_iter *i); void *htable_next(const struct htable *htable, struct htable_iter *i); /** - * htable_delval - remove an iterated pointer from a hash tree + * htable_delval - remove an iterated pointer from a hash table * @ht: the htable * @i: the htable_iter *