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Diffstat (limited to 'mkfs.ubifs/hashtable/hashtable.h')
-rw-r--r-- | mkfs.ubifs/hashtable/hashtable.h | 199 |
1 files changed, 0 insertions, 199 deletions
diff --git a/mkfs.ubifs/hashtable/hashtable.h b/mkfs.ubifs/hashtable/hashtable.h deleted file mode 100644 index c0b0acd..0000000 --- a/mkfs.ubifs/hashtable/hashtable.h +++ /dev/null @@ -1,199 +0,0 @@ -/* Copyright (C) 2002 Christopher Clark <firstname.lastname@cl.cam.ac.uk> */ - -#ifndef __HASHTABLE_CWC22_H__ -#define __HASHTABLE_CWC22_H__ - -struct hashtable; - -/* Example of use: - * - * struct hashtable *h; - * struct some_key *k; - * struct some_value *v; - * - * static unsigned int hash_from_key_fn( void *k ); - * static int keys_equal_fn ( void *key1, void *key2 ); - * - * h = create_hashtable(16, hash_from_key_fn, keys_equal_fn); - * k = (struct some_key *) malloc(sizeof(struct some_key)); - * v = (struct some_value *) malloc(sizeof(struct some_value)); - * - * (initialise k and v to suitable values) - * - * if (! hashtable_insert(h,k,v) ) - * { exit(-1); } - * - * if (NULL == (found = hashtable_search(h,k) )) - * { printf("not found!"); } - * - * if (NULL == (found = hashtable_remove(h,k) )) - * { printf("Not found\n"); } - * - */ - -/* Macros may be used to define type-safe(r) hashtable access functions, with - * methods specialized to take known key and value types as parameters. - * - * Example: - * - * Insert this at the start of your file: - * - * DEFINE_HASHTABLE_INSERT(insert_some, struct some_key, struct some_value); - * DEFINE_HASHTABLE_SEARCH(search_some, struct some_key, struct some_value); - * DEFINE_HASHTABLE_REMOVE(remove_some, struct some_key, struct some_value); - * - * This defines the functions 'insert_some', 'search_some' and 'remove_some'. - * These operate just like hashtable_insert etc., with the same parameters, - * but their function signatures have 'struct some_key *' rather than - * 'void *', and hence can generate compile time errors if your program is - * supplying incorrect data as a key (and similarly for value). - * - * Note that the hash and key equality functions passed to create_hashtable - * still take 'void *' parameters instead of 'some key *'. This shouldn't be - * a difficult issue as they're only defined and passed once, and the other - * functions will ensure that only valid keys are supplied to them. - * - * The cost for this checking is increased code size and runtime overhead - * - if performance is important, it may be worth switching back to the - * unsafe methods once your program has been debugged with the safe methods. - * This just requires switching to some simple alternative defines - eg: - * #define insert_some hashtable_insert - * - */ - -/***************************************************************************** - * create_hashtable - - * @name create_hashtable - * @param minsize minimum initial size of hashtable - * @param hashfunction function for hashing keys - * @param key_eq_fn function for determining key equality - * @return newly created hashtable or NULL on failure - */ - -struct hashtable * -create_hashtable(unsigned int minsize, - unsigned int (*hashfunction) (void*), - int (*key_eq_fn) (void*,void*)); - -/***************************************************************************** - * hashtable_insert - - * @name hashtable_insert - * @param h the hashtable to insert into - * @param k the key - hashtable claims ownership and will free on removal - * @param v the value - does not claim ownership - * @return non-zero for successful insertion - * - * This function will cause the table to expand if the insertion would take - * the ratio of entries to table size over the maximum load factor. - * - * This function does not check for repeated insertions with a duplicate key. - * The value returned when using a duplicate key is undefined -- when - * the hashtable changes size, the order of retrieval of duplicate key - * entries is reversed. - * If in doubt, remove before insert. - */ - -int -hashtable_insert(struct hashtable *h, void *k, void *v); - -#define DEFINE_HASHTABLE_INSERT(fnname, keytype, valuetype) \ -int fnname (struct hashtable *h, keytype *k, valuetype *v) \ -{ \ - return hashtable_insert(h,k,v); \ -} - -/***************************************************************************** - * hashtable_search - - * @name hashtable_search - * @param h the hashtable to search - * @param k the key to search for - does not claim ownership - * @return the value associated with the key, or NULL if none found - */ - -void * -hashtable_search(struct hashtable *h, void *k); - -#define DEFINE_HASHTABLE_SEARCH(fnname, keytype, valuetype) \ -valuetype * fnname (struct hashtable *h, keytype *k) \ -{ \ - return (valuetype *) (hashtable_search(h,k)); \ -} - -/***************************************************************************** - * hashtable_remove - - * @name hashtable_remove - * @param h the hashtable to remove the item from - * @param k the key to search for - does not claim ownership - * @return the value associated with the key, or NULL if none found - */ - -void * /* returns value */ -hashtable_remove(struct hashtable *h, void *k); - -#define DEFINE_HASHTABLE_REMOVE(fnname, keytype, valuetype) \ -valuetype * fnname (struct hashtable *h, keytype *k) \ -{ \ - return (valuetype *) (hashtable_remove(h,k)); \ -} - - -/***************************************************************************** - * hashtable_count - - * @name hashtable_count - * @param h the hashtable - * @return the number of items stored in the hashtable - */ -unsigned int -hashtable_count(struct hashtable *h); - - -/***************************************************************************** - * hashtable_destroy - - * @name hashtable_destroy - * @param h the hashtable - * @param free_values whether to call 'free' on the remaining values - */ - -void -hashtable_destroy(struct hashtable *h, int free_values); - -#endif /* __HASHTABLE_CWC22_H__ */ - -/* - * Copyright (c) 2002, Christopher Clark - * All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * - * * Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * - * * Redistributions in binary form must reproduce the above copyright - * notice, this list of conditions and the following disclaimer in the - * documentation and/or other materials provided with the distribution. - * - * * Neither the name of the original author; nor the names of any contributors - * may be used to endorse or promote products derived from this software - * without specific prior written permission. - * - * - * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS - * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT - * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR - * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER - * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, - * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, - * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR - * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF - * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING - * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS - * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. -*/ |