| /* 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 <openssl/base.h> |
| #include <openssl/type_check.h> |
| |
| #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 DEFINE_LHASH_OF(type) LHASH_OF(type) { int dummy; } |
| |
| #define DECLARE_LHASH_OF(type) LHASH_OF(type); |
| |
| /* The make_macros.sh script in this directory parses the following lines and |
| * generates the lhash_macros.h file that contains macros for the following |
| * types of stacks: |
| * |
| * LHASH_OF:ASN1_OBJECT |
| * LHASH_OF:CONF_VALUE |
| * LHASH_OF:CRYPTO_BUFFER |
| * LHASH_OF:SSL_SESSION */ |
| |
| #define IN_LHASH_H |
| #include <openssl/lhash_macros.h> |
| #undef IN_LHASH_H |
| |
| |
| /* 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. */ |
| typedef int (*lhash_cmp_func)(const void *a, const void *b); |
| |
| /* lhash_hash_func is a function that maps an object to a uniformly distributed |
| * uint32_t. */ |
| typedef uint32_t (*lhash_hash_func)(const void *a); |
| |
| typedef struct lhash_st { |
| /* num_items contains the total number of items in the hash table. */ |
| size_t num_items; |
| /* buckets is an array of |num_buckets| pointers. Each points to the head of |
| * a chain of LHASH_ITEM objects that have the same hash value, mod |
| * |num_buckets|. */ |
| LHASH_ITEM **buckets; |
| /* num_buckets contains the length of |buckets|. This value is always >= |
| * kMinNumBuckets. */ |
| size_t num_buckets; |
| /* callback_depth contains the current depth of |lh_doall| or |lh_doall_arg| |
| * calls. If non-zero then this suppresses resizing of the |buckets| array, |
| * which would otherwise disrupt the iteration. */ |
| unsigned callback_depth; |
| |
| lhash_cmp_func comp; |
| lhash_hash_func hash; |
| } _LHASH; |
| |
| /* lh_new returns a new, empty hash table or NULL on error. If |comp| is NULL, |
| * |strcmp| will be used. If |hash| is NULL, a generic hash function will be |
| * used. */ |
| 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); |
| |
| /* 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); |
| |
| /* 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); |
| |
| /* lh_doall calls |func| on each element of the hash table. |
| * TODO(fork): rename this */ |
| OPENSSL_EXPORT void lh_doall(_LHASH *lh, void (*func)(void *)); |
| |
| /* 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); |
| |
| |
| #if defined(__cplusplus) |
| } /* extern C */ |
| #endif |
| |
| #endif /* OPENSSL_HEADER_LHASH_H */ |