- /* 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: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_STACK_H */
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