/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) * All rights reserved. * * This package is an SSL implementation written * by Eric Young (eay@cryptsoft.com). * The implementation was written so as to conform with Netscapes SSL. * * This library is free for commercial and non-commercial use as long as * the following conditions are aheared to. The following conditions * apply to all code found in this distribution, be it the RC4, RSA, * lhash, DES, etc., code; not just the SSL code. The SSL documentation * included with this distribution is covered by the same copyright terms * except that the holder is Tim Hudson (tjh@cryptsoft.com). * * Copyright remains Eric Young's, and as such any Copyright notices in * the code are not to be removed. * If this package is used in a product, Eric Young should be given attribution * as the author of the parts of the library used. * This can be in the form of a textual message at program startup or * in documentation (online or textual) provided with the package. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the copyright * notice, this list of conditions and the following disclaimer. * 2. 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. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * "This product includes cryptographic software written by * Eric Young (eay@cryptsoft.com)" * The word 'cryptographic' can be left out if the rouines from the library * being used are not cryptographic related :-). * 4. If you include any Windows specific code (or a derivative thereof) from * the apps directory (application code) you must include an acknowledgement: * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" * * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``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 AUTHOR 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. * * The licence and distribution terms for any publically available version or * derivative of this code cannot be changed. i.e. this code cannot simply be * copied and put under another distribution licence * [including the GNU Public Licence.] */ #ifndef OPENSSL_HEADER_LHASH_H #define OPENSSL_HEADER_LHASH_H #include #include #if defined(__cplusplus) extern "C" { #endif // lhash is a traditional, chaining hash table that automatically expands and // contracts as needed. One should not use the lh_* functions directly, rather // use the type-safe macro wrappers: // // A hash table of a specific type of object has type |LHASH_OF(type)|. This // can be defined (once) with |DEFINE_LHASH_OF(type)| and declared where needed // with |DECLARE_LHASH_OF(type)|. For example: // // struct foo { // int bar; // }; // // DEFINE_LHASH_OF(struct foo); // // Although note that the hash table will contain /pointers/ to |foo|. // // A macro will be defined for each of the lh_* functions below. For // LHASH_OF(foo), the macros would be lh_foo_new, lh_foo_num_items etc. #define LHASH_OF(type) struct lhash_st_##type #define DECLARE_LHASH_OF(type) LHASH_OF(type); // lhash_item_st is an element of a hash chain. It points to the opaque data // for this element and to the next item in the chain. The linked-list is NULL // terminated. typedef struct lhash_item_st { void *data; struct lhash_item_st *next; // hash contains the cached, hash value of |data|. uint32_t hash; } LHASH_ITEM; // lhash_cmp_func is a comparison function that returns a value equal, or not // equal, to zero depending on whether |*a| is equal, or not equal to |*b|, // respectively. Note the difference between this and |stack_cmp_func| in that // this takes pointers to the objects directly. // // This function's actual type signature is int (*)(const T*, const T*). The // low-level |lh_*| functions will be passed a type-specific wrapper to call it // correctly. typedef int (*lhash_cmp_func)(const void *a, const void *b); typedef int (*lhash_cmp_func_helper)(lhash_cmp_func func, const void *a, const void *b); // lhash_hash_func is a function that maps an object to a uniformly distributed // uint32_t. // // This function's actual type signature is uint32_t (*)(const T*). The // low-level |lh_*| functions will be passed a type-specific wrapper to call it // correctly. typedef uint32_t (*lhash_hash_func)(const void *a); typedef uint32_t (*lhash_hash_func_helper)(lhash_hash_func func, const void *a); typedef struct lhash_st _LHASH; // lh_new returns a new, empty hash table or NULL on error. OPENSSL_EXPORT _LHASH *lh_new(lhash_hash_func hash, lhash_cmp_func comp); // lh_free frees the hash table itself but none of the elements. See // |lh_doall|. OPENSSL_EXPORT void lh_free(_LHASH *lh); // lh_num_items returns the number of items in |lh|. OPENSSL_EXPORT size_t lh_num_items(const _LHASH *lh); // lh_retrieve finds an element equal to |data| in the hash table and returns // it. If no such element exists, it returns NULL. OPENSSL_EXPORT void *lh_retrieve(const _LHASH *lh, const void *data, lhash_hash_func_helper call_hash_func, lhash_cmp_func_helper call_cmp_func); // lh_retrieve_key finds an element matching |key|, given the specified hash and // comparison function. This differs from |lh_retrieve| in that the key may be a // different type than the values stored in |lh|. |key_hash| and |cmp_key| must // be compatible with the functions passed into |lh_new|. OPENSSL_EXPORT void *lh_retrieve_key(const _LHASH *lh, const void *key, uint32_t key_hash, int (*cmp_key)(const void *key, const void *value)); // lh_insert inserts |data| into the hash table. If an existing element is // equal to |data| (with respect to the comparison function) then |*old_data| // will be set to that value and it will be replaced. Otherwise, or in the // event of an error, |*old_data| will be set to NULL. It returns one on // success or zero in the case of an allocation error. OPENSSL_EXPORT int lh_insert(_LHASH *lh, void **old_data, void *data, lhash_hash_func_helper call_hash_func, lhash_cmp_func_helper call_cmp_func); // lh_delete removes an element equal to |data| from the hash table and returns // it. If no such element is found, it returns NULL. OPENSSL_EXPORT void *lh_delete(_LHASH *lh, const void *data, lhash_hash_func_helper call_hash_func, lhash_cmp_func_helper call_cmp_func); // lh_doall_arg calls |func| on each element of the hash table and also passes // |arg| as the second argument. // TODO(fork): rename this OPENSSL_EXPORT void lh_doall_arg(_LHASH *lh, void (*func)(void *, void *), void *arg); // lh_strhash is the default hash function which processes NUL-terminated // strings. OPENSSL_EXPORT uint32_t lh_strhash(const char *c); #define DEFINE_LHASH_OF(type) \ DECLARE_LHASH_OF(type) \ \ typedef int (*lhash_##type##_cmp_func)(const type *, const type *); \ typedef uint32_t (*lhash_##type##_hash_func)(const type *); \ \ OPENSSL_INLINE int lh_##type##_call_cmp_func(lhash_cmp_func func, \ const void *a, const void *b) { \ return ((lhash_##type##_cmp_func)func)((const type *)a, (const type *)b); \ } \ \ OPENSSL_INLINE uint32_t lh_##type##_call_hash_func(lhash_hash_func func, \ const void *a) { \ return ((lhash_##type##_hash_func)func)((const type *)a); \ } \ \ OPENSSL_INLINE LHASH_OF(type) * \ lh_##type##_new(lhash_##type##_hash_func hash, \ lhash_##type##_cmp_func comp) { \ return (LHASH_OF(type) *)lh_new((lhash_hash_func)hash, \ (lhash_cmp_func)comp); \ } \ \ OPENSSL_INLINE void lh_##type##_free(LHASH_OF(type) *lh) { \ lh_free((_LHASH *)lh); \ } \ \ OPENSSL_INLINE size_t lh_##type##_num_items(const LHASH_OF(type) *lh) { \ return lh_num_items((const _LHASH *)lh); \ } \ \ OPENSSL_INLINE type *lh_##type##_retrieve(const LHASH_OF(type) *lh, \ const type *data) { \ return (type *)lh_retrieve((const _LHASH *)lh, data, \ lh_##type##_call_hash_func, \ lh_##type##_call_cmp_func); \ } \ \ typedef struct { \ int (*cmp_key)(const void *key, const type *value); \ const void *key; \ } LHASH_CMP_KEY_##type; \ \ OPENSSL_INLINE int lh_##type##_call_cmp_key(const void *key, \ const void *value) { \ const LHASH_CMP_KEY_##type *cb = (const LHASH_CMP_KEY_##type *)key; \ return cb->cmp_key(cb->key, (const type *)value); \ } \ \ OPENSSL_INLINE type *lh_##type##_retrieve_key( \ const LHASH_OF(type) *lh, const void *key, uint32_t key_hash, \ int (*cmp_key)(const void *key, const type *value)) { \ LHASH_CMP_KEY_##type cb = {cmp_key, key}; \ return (type *)lh_retrieve_key((const _LHASH *)lh, &cb, key_hash, \ lh_##type##_call_cmp_key); \ } \ \ OPENSSL_INLINE int lh_##type##_insert(LHASH_OF(type) *lh, type **old_data, \ type *data) { \ void *old_data_void = NULL; \ int ret = \ lh_insert((_LHASH *)lh, &old_data_void, data, \ lh_##type##_call_hash_func, lh_##type##_call_cmp_func); \ *old_data = (type *)old_data_void; \ return ret; \ } \ \ OPENSSL_INLINE type *lh_##type##_delete(LHASH_OF(type) *lh, \ const type *data) { \ return (type *)lh_delete((_LHASH *)lh, data, lh_##type##_call_hash_func, \ lh_##type##_call_cmp_func); \ } \ \ typedef struct { \ void (*doall)(type *); \ void (*doall_arg)(type *, void *); \ void *arg; \ } LHASH_DOALL_##type; \ \ OPENSSL_INLINE void lh_##type##_call_doall(void *value, void *arg) { \ const LHASH_DOALL_##type *cb = (const LHASH_DOALL_##type *)arg; \ cb->doall((type *)value); \ } \ \ OPENSSL_INLINE void lh_##type##_call_doall_arg(void *value, void *arg) { \ const LHASH_DOALL_##type *cb = (const LHASH_DOALL_##type *)arg; \ cb->doall_arg((type *)value, cb->arg); \ } \ \ OPENSSL_INLINE void lh_##type##_doall(LHASH_OF(type) *lh, \ void (*func)(type *)) { \ LHASH_DOALL_##type cb = {func, NULL, NULL}; \ lh_doall_arg((_LHASH *)lh, lh_##type##_call_doall, &cb); \ } \ \ OPENSSL_INLINE void lh_##type##_doall_arg( \ LHASH_OF(type) *lh, void (*func)(type *, void *), void *arg) { \ LHASH_DOALL_##type cb = {NULL, func, arg}; \ lh_doall_arg((_LHASH *)lh, lh_##type##_call_doall_arg, &cb); \ } #if defined(__cplusplus) } // extern C #endif #endif // OPENSSL_HEADER_LHASH_H