1 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
4 * This package is an SSL implementation written
5 * by Eric Young (eay@cryptsoft.com).
6 * The implementation was written so as to conform with Netscapes SSL.
8 * This library is free for commercial and non-commercial use as long as
9 * the following conditions are aheared to. The following conditions
10 * apply to all code found in this distribution, be it the RC4, RSA,
11 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
12 * included with this distribution is covered by the same copyright terms
13 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15 * Copyright remains Eric Young's, and as such any Copyright notices in
16 * the code are not to be removed.
17 * If this package is used in a product, Eric Young should be given attribution
18 * as the author of the parts of the library used.
19 * This can be in the form of a textual message at program startup or
20 * in documentation (online or textual) provided with the package.
22 * Redistribution and use in source and binary forms, with or without
23 * modification, are permitted provided that the following conditions
25 * 1. Redistributions of source code must retain the copyright
26 * notice, this list of conditions and the following disclaimer.
27 * 2. Redistributions in binary form must reproduce the above copyright
28 * notice, this list of conditions and the following disclaimer in the
29 * documentation and/or other materials provided with the distribution.
30 * 3. All advertising materials mentioning features or use of this software
31 * must display the following acknowledgement:
32 * "This product includes cryptographic software written by
33 * Eric Young (eay@cryptsoft.com)"
34 * The word 'cryptographic' can be left out if the rouines from the library
35 * being used are not cryptographic related :-).
36 * 4. If you include any Windows specific code (or a derivative thereof) from
37 * the apps directory (application code) you must include an acknowledgement:
38 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
41 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
43 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
44 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
45 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
46 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
48 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
49 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
52 * The licence and distribution terms for any publically available version or
53 * derivative of this code cannot be changed. i.e. this code cannot simply be
54 * copied and put under another distribution licence
55 * [including the GNU Public Licence.]
59 * Code for dynamic hash table routines
60 * Author - Eric Young v 2.0
62 * 2.2 eay - added #include "crypto.h" so the memory leak checking code is
63 * present. eay 18-Jun-98
65 * 2.1 eay - Added an 'error in last operation' flag. eay 6-May-98
67 * 2.0 eay - Fixed a bug that occurred when using lh_delete
68 * from inside lh_doall(). As entries were deleted,
69 * the 'table' was 'contract()ed', making some entries
70 * jump from the end of the table to the start, there by
71 * skipping the lh_doall() processing. eay - 4/12/95
73 * 1.9 eay - Fixed a memory leak in lh_free, the LHASH_NODEs
74 * were not being free()ed. 21/11/95
76 * 1.8 eay - Put the stats routines into a separate file, lh_stats.c
79 * 1.7 eay - Removed the fputs() for realloc failures - the code
80 * should silently tolerate them. I have also fixed things
81 * lint complained about 04/05/95
83 * 1.6 eay - Fixed an invalid pointers in contract/expand 27/07/92
85 * 1.5 eay - Fixed a misuse of realloc in expand 02/03/1992
87 * 1.4 eay - Fixed lh_doall so the function can call lh_delete 28/05/91
89 * 1.3 eay - Fixed a few lint problems 19/3/1991
91 * 1.2 eay - Fixed lh_doall problem 13/3/1991
93 * 1.1 eay - Added lh_doall
95 * 1.0 eay - First version
100 #include <openssl/crypto.h>
101 #include <openssl/lhash.h>
105 #define UP_LOAD (2*LH_LOAD_MULT) /* load times 256 (default 2) */
106 #define DOWN_LOAD (LH_LOAD_MULT) /* load times 256 (default 1) */
108 static void expand(_LHASH *lh);
109 static void contract(_LHASH *lh);
110 static LHASH_NODE **getrn(_LHASH *lh, const void *data, unsigned long *rhash);
112 _LHASH *lh_new(LHASH_HASH_FN_TYPE h, LHASH_COMP_FN_TYPE c)
116 if ((ret = OPENSSL_zalloc(sizeof(*ret))) == NULL)
118 if ((ret->b = OPENSSL_zalloc(sizeof(*ret->b) * MIN_NODES)) == NULL)
120 ret->comp = ((c == NULL) ? (LHASH_COMP_FN_TYPE)strcmp : c);
121 ret->hash = ((h == NULL) ? (LHASH_HASH_FN_TYPE)lh_strhash : h);
122 ret->num_nodes = MIN_NODES / 2;
123 ret->num_alloc_nodes = MIN_NODES;
124 ret->pmax = MIN_NODES / 2;
125 ret->up_load = UP_LOAD;
126 ret->down_load = DOWN_LOAD;
135 void lh_free(_LHASH *lh)
143 for (i = 0; i < lh->num_nodes; i++) {
155 void *lh_insert(_LHASH *lh, void *data)
158 LHASH_NODE *nn, **rn;
162 if (lh->up_load <= (lh->num_items * LH_LOAD_MULT / lh->num_nodes))
165 rn = getrn(lh, data, &hash);
168 if ((nn = OPENSSL_malloc(sizeof(*nn))) == NULL) {
179 } else { /* replace same key */
188 void *lh_delete(_LHASH *lh, const void *data)
191 LHASH_NODE *nn, **rn;
195 rn = getrn(lh, data, &hash);
209 if ((lh->num_nodes > MIN_NODES) &&
210 (lh->down_load >= (lh->num_items * LH_LOAD_MULT / lh->num_nodes)))
216 void *lh_retrieve(_LHASH *lh, const void *data)
223 rn = getrn(lh, data, &hash);
226 lh->num_retrieve_miss++;
235 static void doall_util_fn(_LHASH *lh, int use_arg, LHASH_DOALL_FN_TYPE func,
236 LHASH_DOALL_ARG_FN_TYPE func_arg, void *arg)
245 * reverse the order so we search from 'top to bottom' We were having
246 * memory leaks otherwise
248 for (i = lh->num_nodes - 1; i >= 0; i--) {
252 * 28/05/91 - eay - n added so items can be deleted via lh_doall
255 * 22/05/08 - ben - eh? since a is not passed, this should not be
260 func_arg(a->data, arg);
268 void lh_doall(_LHASH *lh, LHASH_DOALL_FN_TYPE func)
270 doall_util_fn(lh, 0, func, (LHASH_DOALL_ARG_FN_TYPE)0, NULL);
273 void lh_doall_arg(_LHASH *lh, LHASH_DOALL_ARG_FN_TYPE func, void *arg)
275 doall_util_fn(lh, 1, (LHASH_DOALL_FN_TYPE)0, func, arg);
278 static void expand(_LHASH *lh)
280 LHASH_NODE **n, **n1, **n2, *np;
281 unsigned int p, i, j;
282 unsigned long hash, nni;
288 n2 = &(lh->b[p + (int)lh->pmax]);
289 *n2 = NULL; /* 27/07/92 - eay - undefined pointer bug */
290 nni = lh->num_alloc_nodes;
292 for (np = *n1; np != NULL;) {
294 if ((hash % nni) != p) { /* move it */
303 if ((lh->p) >= lh->pmax) {
304 j = (int)lh->num_alloc_nodes * 2;
305 n = OPENSSL_realloc(lh->b, (int)(sizeof(LHASH_NODE *) * j));
307 /* fputs("realloc error in lhash",stderr); */
312 for (i = (int)lh->num_alloc_nodes; i < j; i++) /* 26/02/92 eay */
313 n[i] = NULL; /* 02/03/92 eay */
314 lh->pmax = lh->num_alloc_nodes;
315 lh->num_alloc_nodes = j;
316 lh->num_expand_reallocs++;
322 static void contract(_LHASH *lh)
324 LHASH_NODE **n, *n1, *np;
326 np = lh->b[lh->p + lh->pmax - 1];
327 lh->b[lh->p + lh->pmax - 1] = NULL; /* 24/07-92 - eay - weird but :-( */
329 n = OPENSSL_realloc(lh->b,
330 (unsigned int)(sizeof(LHASH_NODE *) * lh->pmax));
332 /* fputs("realloc error in lhash",stderr); */
336 lh->num_contract_reallocs++;
337 lh->num_alloc_nodes /= 2;
339 lh->p = lh->pmax - 1;
347 n1 = lh->b[(int)lh->p];
349 lh->b[(int)lh->p] = np;
351 while (n1->next != NULL)
357 static LHASH_NODE **getrn(_LHASH *lh, const void *data, unsigned long *rhash)
359 LHASH_NODE **ret, *n1;
360 unsigned long hash, nn;
361 LHASH_COMP_FN_TYPE cf;
363 hash = (*(lh->hash)) (data);
364 lh->num_hash_calls++;
367 nn = hash % lh->pmax;
369 nn = hash % lh->num_alloc_nodes;
372 ret = &(lh->b[(int)nn]);
373 for (n1 = *ret; n1 != NULL; n1 = n1->next) {
374 lh->num_hash_comps++;
375 if (n1->hash != hash) {
379 lh->num_comp_calls++;
380 if (cf(n1->data, data) == 0)
388 * The following hash seems to work very well on normal text strings no
389 * collisions on /usr/dict/words and it distributes on %2^n quite well, not
390 * as good as MD5, but still good.
392 unsigned long lh_strhash(const char *c)
394 unsigned long ret = 0;
399 if ((c == NULL) || (*c == '\0'))
404 return(b[0]|(b[1]<<8)|(b[2]<<16)|(b[3]<<24));
411 r = (int)((v >> 2) ^ v) & 0x0f;
412 ret = (ret << r) | (ret >> (32 - r));
417 return ((ret >> 16) ^ ret);
420 unsigned long lh_num_items(const _LHASH *lh)
422 return lh ? lh->num_items : 0;
425 unsigned long lh_get_down_load(const _LHASH *lh)
427 return lh->down_load;
430 void lh_set_down_load(_LHASH *lh, unsigned long down_load)
432 lh->down_load = down_load;
435 int lh_error(_LHASH *lh)