2 * Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved.
4 * Licensed under the Apache License 2.0 (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
11 #include "internal/cryptlib.h"
12 #include "internal/numbers.h"
13 #include <openssl/stack.h>
15 #include <openssl/e_os2.h> /* For ossl_inline */
18 * The initial number of nodes in the array.
20 static const int min_nodes = 4;
21 static const int max_nodes = SIZE_MAX / sizeof(void *) < INT_MAX
22 ? (int)(SIZE_MAX / sizeof(void *))
30 OPENSSL_sk_compfunc comp;
33 OPENSSL_sk_compfunc OPENSSL_sk_set_cmp_func(OPENSSL_STACK *sk, OPENSSL_sk_compfunc c)
35 OPENSSL_sk_compfunc old = sk->comp;
44 OPENSSL_STACK *OPENSSL_sk_dup(const OPENSSL_STACK *sk)
48 if ((ret = OPENSSL_malloc(sizeof(*ret))) == NULL) {
49 CRYPTOerr(CRYPTO_F_OPENSSL_SK_DUP, ERR_R_MALLOC_FAILURE);
53 /* direct structure assignment */
57 /* postpone |ret->data| allocation */
62 /* duplicate |sk->data| content */
63 if ((ret->data = OPENSSL_malloc(sizeof(*ret->data) * sk->num_alloc)) == NULL)
65 memcpy(ret->data, sk->data, sizeof(void *) * sk->num);
72 OPENSSL_STACK *OPENSSL_sk_deep_copy(const OPENSSL_STACK *sk,
73 OPENSSL_sk_copyfunc copy_func,
74 OPENSSL_sk_freefunc free_func)
79 if ((ret = OPENSSL_malloc(sizeof(*ret))) == NULL) {
80 CRYPTOerr(CRYPTO_F_OPENSSL_SK_DEEP_COPY, ERR_R_MALLOC_FAILURE);
84 /* direct structure assignment */
88 /* postpone |ret| data allocation */
94 ret->num_alloc = sk->num > min_nodes ? sk->num : min_nodes;
95 ret->data = OPENSSL_zalloc(sizeof(*ret->data) * ret->num_alloc);
96 if (ret->data == NULL) {
101 for (i = 0; i < ret->num; ++i) {
102 if (sk->data[i] == NULL)
104 if ((ret->data[i] = copy_func(sk->data[i])) == NULL) {
106 if (ret->data[i] != NULL)
107 free_func((void *)ret->data[i]);
108 OPENSSL_sk_free(ret);
115 OPENSSL_STACK *OPENSSL_sk_new_null(void)
117 return OPENSSL_sk_new_reserve(NULL, 0);
120 OPENSSL_STACK *OPENSSL_sk_new(OPENSSL_sk_compfunc c)
122 return OPENSSL_sk_new_reserve(c, 0);
126 * Calculate the array growth based on the target size.
128 * The growth fraction is a rational number and is defined by a numerator
129 * and a denominator. According to Andrew Koenig in his paper "Why Are
130 * Vectors Efficient?" from JOOP 11(5) 1998, this factor should be less
131 * than the golden ratio (1.618...).
133 * We use 3/2 = 1.5 for simplicity of calculation and overflow checking.
134 * Another option 8/5 = 1.6 allows for slightly faster growth, although safe
135 * computation is more difficult.
137 * The limit to avoid overflow is spot on. The modulo three correction term
138 * ensures that the limit is the largest number than can be expanded by the
139 * growth factor without exceeding the hard limit.
141 * Do not call it with |current| lower than 2, or it will infinitely loop.
143 static ossl_inline int compute_growth(int target, int current)
145 const int limit = (max_nodes / 3) * 2 + (max_nodes % 3 ? 1 : 0);
147 while (current < target) {
148 /* Check to see if we're at the hard limit */
149 if (current >= max_nodes)
152 /* Expand the size by a factor of 3/2 if it is within range */
153 current = current < limit ? current + current / 2 : max_nodes;
158 /* internal STACK storage allocation */
159 static int sk_reserve(OPENSSL_STACK *st, int n, int exact)
161 const void **tmpdata;
164 /* Check to see the reservation isn't exceeding the hard limit */
165 if (n > max_nodes - st->num)
168 /* Figure out the new size */
169 num_alloc = st->num + n;
170 if (num_alloc < min_nodes)
171 num_alloc = min_nodes;
173 /* If |st->data| allocation was postponed */
174 if (st->data == NULL) {
176 * At this point, |st->num_alloc| and |st->num| are 0;
177 * so |num_alloc| value is |n| or |min_nodes| if greater than |n|.
179 if ((st->data = OPENSSL_zalloc(sizeof(void *) * num_alloc)) == NULL) {
180 CRYPTOerr(CRYPTO_F_SK_RESERVE, ERR_R_MALLOC_FAILURE);
183 st->num_alloc = num_alloc;
188 if (num_alloc <= st->num_alloc)
190 num_alloc = compute_growth(num_alloc, st->num_alloc);
193 } else if (num_alloc == st->num_alloc) {
197 tmpdata = OPENSSL_realloc((void *)st->data, sizeof(void *) * num_alloc);
202 st->num_alloc = num_alloc;
206 OPENSSL_STACK *OPENSSL_sk_new_reserve(OPENSSL_sk_compfunc c, int n)
208 OPENSSL_STACK *st = OPENSSL_zalloc(sizeof(OPENSSL_STACK));
218 if (!sk_reserve(st, n, 1)) {
226 int OPENSSL_sk_reserve(OPENSSL_STACK *st, int n)
233 return sk_reserve(st, n, 1);
236 int OPENSSL_sk_insert(OPENSSL_STACK *st, const void *data, int loc)
238 if (st == NULL || st->num == max_nodes)
241 if (!sk_reserve(st, 1, 0))
244 if ((loc >= st->num) || (loc < 0)) {
245 st->data[st->num] = data;
247 memmove(&st->data[loc + 1], &st->data[loc],
248 sizeof(st->data[0]) * (st->num - loc));
249 st->data[loc] = data;
256 static ossl_inline void *internal_delete(OPENSSL_STACK *st, int loc)
258 const void *ret = st->data[loc];
260 if (loc != st->num - 1)
261 memmove(&st->data[loc], &st->data[loc + 1],
262 sizeof(st->data[0]) * (st->num - loc - 1));
268 void *OPENSSL_sk_delete_ptr(OPENSSL_STACK *st, const void *p)
272 for (i = 0; i < st->num; i++)
273 if (st->data[i] == p)
274 return internal_delete(st, i);
278 void *OPENSSL_sk_delete(OPENSSL_STACK *st, int loc)
280 if (st == NULL || loc < 0 || loc >= st->num)
283 return internal_delete(st, loc);
286 static int internal_find(OPENSSL_STACK *st, const void *data,
292 if (st == NULL || st->num == 0)
295 if (st->comp == NULL) {
296 for (i = 0; i < st->num; i++)
297 if (st->data[i] == data)
304 qsort(st->data, st->num, sizeof(void *), st->comp);
305 st->sorted = 1; /* empty or single-element stack is considered sorted */
309 r = ossl_bsearch(&data, st->data, st->num, sizeof(void *), st->comp,
312 return r == NULL ? -1 : (int)((const void **)r - st->data);
315 int OPENSSL_sk_find(OPENSSL_STACK *st, const void *data)
317 return internal_find(st, data, OSSL_BSEARCH_FIRST_VALUE_ON_MATCH);
320 int OPENSSL_sk_find_ex(OPENSSL_STACK *st, const void *data)
322 return internal_find(st, data, OSSL_BSEARCH_VALUE_ON_NOMATCH);
325 int OPENSSL_sk_push(OPENSSL_STACK *st, const void *data)
329 return OPENSSL_sk_insert(st, data, st->num);
332 int OPENSSL_sk_unshift(OPENSSL_STACK *st, const void *data)
334 return OPENSSL_sk_insert(st, data, 0);
337 void *OPENSSL_sk_shift(OPENSSL_STACK *st)
339 if (st == NULL || st->num == 0)
341 return internal_delete(st, 0);
344 void *OPENSSL_sk_pop(OPENSSL_STACK *st)
346 if (st == NULL || st->num == 0)
348 return internal_delete(st, st->num - 1);
351 void OPENSSL_sk_zero(OPENSSL_STACK *st)
353 if (st == NULL || st->num == 0)
355 memset(st->data, 0, sizeof(*st->data) * st->num);
359 void OPENSSL_sk_pop_free(OPENSSL_STACK *st, OPENSSL_sk_freefunc func)
365 for (i = 0; i < st->num; i++)
366 if (st->data[i] != NULL)
367 func((char *)st->data[i]);
371 void OPENSSL_sk_free(OPENSSL_STACK *st)
375 OPENSSL_free(st->data);
379 int OPENSSL_sk_num(const OPENSSL_STACK *st)
381 return st == NULL ? -1 : st->num;
384 void *OPENSSL_sk_value(const OPENSSL_STACK *st, int i)
386 if (st == NULL || i < 0 || i >= st->num)
388 return (void *)st->data[i];
391 void *OPENSSL_sk_set(OPENSSL_STACK *st, int i, const void *data)
393 if (st == NULL || i < 0 || i >= st->num)
397 return (void *)st->data[i];
400 void OPENSSL_sk_sort(OPENSSL_STACK *st)
402 if (st != NULL && !st->sorted && st->comp != NULL) {
404 qsort(st->data, st->num, sizeof(void *), st->comp);
405 st->sorted = 1; /* empty or single-element stack is considered sorted */
409 int OPENSSL_sk_is_sorted(const OPENSSL_STACK *st)
411 return st == NULL ? 1 : st->sorted;