From ff76efc3e5e1b0e4ca3b10b7402406f619509bba Mon Sep 17 00:00:00 2001 From: Stef Walter Date: Wed, 21 Apr 2004 17:37:06 +0000 Subject: Initial Import --- common/hash.h | 171 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 171 insertions(+) create mode 100644 common/hash.h (limited to 'common/hash.h') diff --git a/common/hash.h b/common/hash.h new file mode 100644 index 0000000..9e8174c --- /dev/null +++ b/common/hash.h @@ -0,0 +1,171 @@ +/* + * Originally from apache 2.0 + * Modifications for general use by + */ + +/* Copyright 2000-2004 The Apache Software Foundation + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#ifndef __HASH_H__ +#define __HASH_H__ + +/* + * Options to define. You need to build both this file and + * the corresponding hash.c file with whatever options you set here + */ + +/* Keep timestamps for the entries */ +#define HASH_TIMESTAMP 1 + +/* Keep key values internally */ +#define HASH_COPYKEYS 1 + + +#ifdef __cplusplus +extern "C" { +#endif + +/** + * When passing a key to hash_set or hash_get, this value can be passed to + * indicate a string-valued key, and have hash compute the length automatically. + */ +#define HASH_KEY_STRING (-1) + +/* Abstract type for hash tables. */ +typedef struct hash_t hash_t; + +/* Abstract type for scanning hash tables. */ +typedef struct hash_index_t hash_index_t; + +/* Create a hash table */ +#ifdef HASH_COPYKEYS + hash_t* hash_create(size_t klen); +#else + hash_t* hash_create(); +#endif + +/* To release all resources for a hash table */ +void hash_free(hash_t* ht); + +/** + * Associate a value with a key in a hash table. + * + * ht The hash table + * key Pointer to the key + * klen Length of the key. Can be HASH_KEY_STRING to use the string length. + * val Value to associate with the key + * + * val must not be null + */ +#ifdef HASH_COPYKEYS + int hash_set(hash_t* ht, const void* key, const void* val); +#else + int hash_set(hash_t* ht, const void* key, size_t klen, const void* val); +#endif + +/** + * Remove a value and key form the hash table + * + * ht The hash table + * key Pointer to the key + * klen Length of the key. Can be HASH_KEY_STRING to use the string length + */ +#ifdef HASH_COPYKEYS + void hash_rem(hash_t* ht, const void* key); +#else + void hash_rem(hash_t* ht, const void* key, size_t klen); +#endif + +/** + * Look up the value associated with a key in a hash table. + * + * ht The hash table + * key Pointer to the key + * klen Length of the key. Can be APR_HASH_KEY_STRING to use the string length. + * + * Returns NULL if the key is not present. + */ +#ifdef HASH_COPYKEYS + void* hash_get(hash_t* ht, const void* key); +#else + void* hash_get(hash_t* ht, const void* key, size_t klen); +#endif + +/** + * Start iterating over the entries in a hash table. + * + * ht The hash table + * + * There is no restriction on adding or deleting hash entries during + * an iteration (although the results may be unpredictable unless all you do + * is delete the current entry). Only one iteration can be in progress at once. + */ +hash_index_t* hash_first(hash_t* ht); + +/** + * Continue iterating over the entries in a hash table. + * + * hi The iteration state + * + * Returns a pointer to the updated iteration state. + * NULL if there are no more entries. + */ +hash_index_t* hash_next(hash_index_t* hi); + +/** + * Get the current entry's details from the iteration state. + * + * hi The iteration state + * key Return pointer for the pointer to the key. + * klen Return pointer for the key length. + * val Return pointer for the associated value. + * + * The return pointers should point to a variable that will be set to the + * corresponding data, or they may be NULL if the data isn't interesting. + */ +#ifdef HASH_COPYKEYS + void* hash_this(hash_index_t* hi, const void** key); +#else + void* hash_this(hash_index_t* hi, const void** key, size_t* klen); +#endif + +/** + * Purge entries before a certain timestamp + */ +#ifdef HASH_TIMESTAMP +int hash_purge(hash_t* ht, time_t stamp); + +#ifdef HASH_COPYKEYS + void hash_touch(hash_index_t* hi, const void** key); +#else + void hash_touch(hash_index_t* hi, const void** key, size_t* klen); +#endif +#endif + +/** + * Get the number of key/value pairs in the hash table. + * + * ht The hash table + * + * The number of key/value pairs in the hash table. + */ +unsigned int hash_count(hash_t* ht); + + +#ifdef __cplusplus +} +#endif + +#endif /* __HASH_H__ */ -- cgit v1.2.3