| /* |
| * Copyright 2004,2005 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 AXIS2_HASH_H |
| #define AXIS2_HASH_H |
| |
| /** |
| * @file axis2_hash.h |
| * @brief Axis2 Hash Tables |
| */ |
| |
| #include <axis2_defines.h> |
| #include <axis2_env.h> |
| |
| #ifdef __cplusplus |
| extern "C" |
| { |
| #endif |
| |
| /** |
| * @defgroup axis2_hash Hash Tables |
| * @ingroup axis2_util |
| * @{ |
| */ |
| |
| /** |
| * When passing a key to axis2_hash_set or axis2_hash_get, this value can be |
| * passed to indicate a string-valued key, and have axis2_hash compute the |
| * length automatically. |
| * |
| * @remark axis2_hash will use strlen(key) for the length. The NUL terminator |
| * is not included in the hash value (why throw a constant in?). |
| * Since the hash table merely references the provided key (rather |
| * than copying it), axis2_hash_this() will return the NUL-term'd key. |
| */ |
| #define AXIS2_HASH_KEY_STRING (-1) |
| |
| /** |
| * Abstract type for hash tables. |
| */ |
| typedef struct axis2_hash_t axis2_hash_t; |
| |
| /** |
| * Abstract type for scanning hash tables. |
| */ |
| typedef struct axis2_hash_index_t axis2_hash_index_t; |
| |
| /** |
| * Callback functions for calculating hash values. |
| * @param key The key. |
| * @param klen The length of the key, or AXIS2_HASH_KEY_STRING to use the string |
| * length. If AXIS2_HASH_KEY_STRING then returns the actual key length. |
| */ |
| typedef unsigned int (*axis2_hashfunc_t) (const char *key, axis2_ssize_t *klen); |
| |
| /** |
| * The default hash function. |
| */ |
| unsigned int axis2_hashfunc_default (const char *key, axis2_ssize_t *klen); |
| |
| /** |
| * Create a hash table. |
| * @param environment The environment to allocate the hash table out of |
| * @return The hash table just created |
| */ |
| AXIS2_DECLARE(axis2_hash_t*) axis2_hash_make (axis2_env_t **environment); |
| |
| /** |
| * Create a hash table with a custom hash function |
| * @param environment The environment to allocate the hash table out of |
| * @param hash_func A custom hash function. |
| * @return The hash table just created |
| */ |
| AXIS2_DECLARE(axis2_hash_t*) axis2_hash_make_custom (axis2_env_t **environment |
| , axis2_hashfunc_t hash_func); |
| |
| /** |
| * Make a copy of a hash table |
| * @param ht The hash table to clone |
| * @param environment The environment from which to allocate the new hash table |
| * @return The hash table just created |
| * @remark Makes a shallow copy |
| */ |
| AXIS2_DECLARE(axis2_hash_t*) axis2_hash_copy (const axis2_hash_t *ht |
| , axis2_env_t **environment); |
| |
| /** |
| * Associate a value with a key in a hash table. |
| * @param ht The hash table |
| * @param key Pointer to the key |
| * @param klen Length of the key. Can be AXIS2_HASH_KEY_STRING to use the string length. |
| * @param val Value to associate with the key |
| * @remark If the value is NULL the hash entry is deleted. |
| */ |
| AXIS2_DECLARE(void) axis2_hash_set (axis2_hash_t *ht, const void *key |
| , axis2_ssize_t klen, const void *val); |
| |
| /** |
| * Look up the value associated with a key in a hash table. |
| * @param ht The hash table |
| * @param key Pointer to the key |
| * @param klen Length of the key. Can be AXIS2_HASH_KEY_STRING to use the string length. |
| * @return Returns NULL if the key is not present. |
| */ |
| AXIS2_DECLARE(void*) axis2_hash_get (axis2_hash_t *ht, const void *key |
| , axis2_ssize_t klen); |
| |
| /** |
| * Start iterating over the entries in a hash table. |
| * @param ht The hash table |
| * @param p The environment to allocate the axis2_hash_index_t iterator. If this |
| * environment is NULL, then an internal, non-thread-safe iterator is used. |
| * @remark 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) and multiple iterations can be in |
| * progress at the same time. |
| |
| * @example |
| */ |
| /** |
| * <PRE> |
| * |
| * int sum_values(axis2_env_t *environment, axis2_hash_t *ht) |
| * { |
| * axis2_hash_index_t *hi; |
| * void *val; |
| * int sum = 0; |
| * for (hi = axis2_hash_first(p, ht); hi; hi = axis2_hash_next(p, hi)) { |
| * axis2_hash_this(hi, NULL, NULL, &val); |
| * sum += *(int *)val; |
| * } |
| * return sum; |
| * } |
| * </PRE> |
| */ |
| AXIS2_DECLARE(axis2_hash_index_t*) axis2_hash_first (axis2_hash_t *ht |
| ,axis2_env_t **environment); |
| |
| /** |
| * Continue iterating over the entries in a hash table. |
| * @param hi The iteration state |
| * @return a pointer to the updated iteration state. NULL if there are no more |
| * entries. |
| */ |
| AXIS2_DECLARE(axis2_hash_index_t*) axis2_hash_next (axis2_env_t **environment |
| , axis2_hash_index_t *hi); |
| |
| /** |
| * Get the current entry's details from the iteration state. |
| * @param hi The iteration state |
| * @param key Return pointer for the pointer to the key. |
| * @param klen Return pointer for the key length. |
| * @param val Return pointer for the associated value. |
| * @remark 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. |
| */ |
| AXIS2_DECLARE(void) axis2_hash_this (axis2_hash_index_t *hi, const void **key |
| , axis2_ssize_t *klen, void **val); |
| |
| /** |
| * Get the number of key/value pairs in the hash table. |
| * @param ht The hash table |
| * @return The number of key/value pairs in the hash table. |
| */ |
| unsigned int axis2_hash_count (axis2_hash_t *ht); |
| |
| /** |
| * Merge two hash tables into one new hash table. The values of the overlay |
| * hash override the values of the base if both have the same key. Both |
| * hash tables must use the same hash function. |
| * @param overlay The table to add to the initial table |
| * @param p The environment to use for the new hash table |
| * @param base The table that represents the initial values of the new table |
| * @return A new hash table containing all of the data from the two passed in |
| */ |
| AXIS2_DECLARE(axis2_hash_t*) axis2_hash_overlay (const axis2_hash_t *overlay |
| ,axis2_env_t **environment, const axis2_hash_t *base); |
| |
| /** |
| * Merge two hash tables into one new hash table. If the same key |
| * is present in both tables, call the supplied merge function to |
| * produce a merged value for the key in the new table. Both |
| * hash tables must use the same hash function. |
| * @param h1 The first of the tables to merge |
| * @param p The environment to use for the new hash table |
| * @param h2 The second of the tables to merge |
| * @param merger A callback function to merge values, or NULL to |
| * make values from h1 override values from h2 (same semantics as |
| * axis2_hash_overlay()) |
| * @param data Client data to pass to the merger function |
| * @return A new hash table containing all of the data from the two passed in |
| */ |
| AXIS2_DECLARE(axis2_hash_t*) axis2_hash_merge (const axis2_hash_t *h1 |
| , axis2_env_t **environment, const axis2_hash_t *h2 |
| , void *(*merger) (axis2_env_t *environment, const void *key |
| , axis2_ssize_t klen, const void *h1_val, const void *h2_val |
| , const void *data), const void *data); |
| |
| |
| /** |
| * @param ht hash table to be freed |
| * @param environment The environment to use for hash table |
| * @return return status code |
| * |
| */ |
| |
| AXIS2_DECLARE(axis2_status_t) axis2_hash_free(axis2_hash_t *ht |
| , axis2_env_t **environment); |
| |
| |
| |
| /** @} */ |
| |
| #ifdef __cplusplus |
| } |
| #endif |
| |
| #endif /* !AXIS2_HASH_H */ |