5 DEFINE_STACK_OF, DEFINE_STACK_OF_CONST, DEFINE_SPECIAL_STACK_OF,
6 DEFINE_SPECIAL_STACK_OF_CONST,
7 OPENSSL_sk_deep_copy, OPENSSL_sk_delete, OPENSSL_sk_delete_ptr,
8 OPENSSL_sk_dup, OPENSSL_sk_find, OPENSSL_sk_find_ex, OPENSSL_sk_free,
9 OPENSSL_sk_insert, OPENSSL_sk_is_sorted, OPENSSL_sk_new, OPENSSL_sk_new_null,
10 OPENSSL_sk_num, OPENSSL_sk_pop, OPENSSL_sk_pop_free, OPENSSL_sk_push,
11 OPENSSL_sk_set, OPENSSL_sk_set_cmp_func, OPENSSL_sk_shift, OPENSSL_sk_sort,
12 OPENSSL_sk_unshift, OPENSSL_sk_value, OPENSSL_sk_zero,
13 sk_TYPE_num, sk_TYPE_value, sk_TYPE_new, sk_TYPE_new_null, sk_TYPE_free,
14 sk_TYPE_zero, sk_TYPE_delete, sk_TYPE_delete_ptr, sk_TYPE_push,
15 sk_TYPE_unshift, sk_TYPE_pop, sk_TYPE_shift, sk_TYPE_pop_free,
16 sk_TYPE_insert, sk_TYPE_set, sk_TYPE_find, sk_TYPE_find_ex, sk_TYPE_sort,
17 sk_TYPE_is_sorted, sk_TYPE_dup, sk_TYPE_deep_copy, sk_TYPE_set_cmp_func -
24 #include <openssl/safestack.h>
28 DEFINE_STACK_OF_CONST(TYPE)
29 DEFINE_SPECIAL_STACK_OF(FUNCTYPE, TYPE)
30 DEFINE_SPECIAL_STACK_OF_CONST(FUNCTYPE, TYPE)
32 typedef int (*sk_TYPE_compfunc)(const TYPE *const *a, const TYPE *const *b);
33 typedef TYPE * (*sk_TYPE_copyfunc)(const TYPE *a);
34 typedef void (*sk_TYPE_freefunc)(TYPE *a);
36 int sk_TYPE_num(const STACK_OF(TYPE) *sk);
37 TYPE *sk_TYPE_value(const STACK_OF(TYPE) *sk, int idx);
38 STACK_OF(TYPE) *sk_TYPE_new(sk_TYPE_compfunc compare);
39 STACK_OF(TYPE) *sk_TYPE_new_null(void);
40 void sk_TYPE_free(const STACK_OF(TYPE) *sk);
41 void sk_TYPE_zero(const STACK_OF(TYPE) *sk);
42 TYPE *sk_TYPE_delete(STACK_OF(TYPE) *sk, int i);
43 TYPE *sk_TYPE_delete_ptr(STACK_OF(TYPE) *sk, TYPE *ptr);
44 int sk_TYPE_push(STACK_OF(TYPE) *sk, const TYPE *ptr);
45 int sk_TYPE_unshift(STACK_OF(TYPE) *sk, const TYPE *ptr);
46 TYPE *sk_TYPE_pop(STACK_OF(TYPE) *sk);
47 TYPE *sk_TYPE_shift(STACK_OF(TYPE) *sk);
48 void sk_TYPE_pop_free(STACK_OF(TYPE) *sk, sk_TYPE_freefunc freefunc);
49 int sk_TYPE_insert(STACK_OF(TYPE) *sk, TYPE *ptr, int idx);
50 TYPE *sk_TYPE_set(STACK_OF(TYPE) *sk, int idx, const TYPE *ptr);
51 int sk_TYPE_find(STACK_OF(TYPE) *sk, TYPE *ptr);
52 int sk_TYPE_find_ex(STACK_OF(TYPE) *sk, TYPE *ptr);
53 void sk_TYPE_sort(const STACK_OF(TYPE) *sk);
54 int sk_TYPE_is_sorted(const STACK_OF(TYPE) *sk);
55 STACK_OF(TYPE) *sk_TYPE_dup(const STACK_OF(TYPE) *sk);
56 STACK_OF(TYPE) *sk_TYPE_deep_copy(const STACK_OF(TYPE) *sk,
57 sk_TYPE_copyfunc copyfunc,
58 sk_TYPE_freefunc freefunc);
59 sk_TYPE_compfunc (*sk_TYPE_set_cmp_func(STACK_OF(TYPE) *sk, sk_TYPE_compfunc compare);
63 Applications can create and use their own stacks by placing any of the macros
64 described below in a header file. These macros define typesafe inline
65 functions that wrap around the utility B<OPENSSL_sk_> API.
66 In the description here, I<TYPE> is used
67 as a placeholder for any of the OpenSSL datatypes, such as I<X509>.
69 STACK_OF() returns the name for a stack of the specified B<TYPE>.
70 DEFINE_STACK_OF() creates set of functions for a stack of B<TYPE>. This
71 will mean that type B<TYPE> is stored in each stack, the type is referenced by
72 STACK_OF(TYPE) and each function name begins with I<sk_TYPE_>. For example:
74 TYPE *sk_TYPE_value(STACK_OF(TYPE) *sk, int idx);
76 DEFINE_STACK_OF_CONST() is identical to DEFINE_STACK_OF() except
77 each element is constant. For example:
79 const TYPE *sk_TYPE_value(STACK_OF(TYPE) *sk, int idx);
81 DEFINE_SPECIAL_STACK_OF() defines a stack of B<TYPE> but
82 each function uses B<FUNCNAME> in the function name. For example:
84 TYPE *sk_FUNCNAME_value(STACK_OF(TYPE) *sk, int idx);
86 DEFINE_SPECIAL_STACK_OF_CONST() is similar except that each element is
89 const TYPE *sk_FUNCNAME_value(STACK_OF(TYPE) *sk, int idx);
91 sk_TYPE_num() returns the number of elements in B<sk> or -1 if B<sk> is
94 sk_TYPE_value() returns element B<idx> in B<sk>, where B<idx> starts at
95 zero. If B<idx> is out of range then B<NULL> is returned.
97 sk_TYPE_new() allocates a new empty stack using comparison function B<compar>.
98 If B<compar> is B<NULL> then no comparison function is used.
100 sk_TYPE_new_null() allocates a new empty stack with no comparison function.
102 sk_TYPE_set_cmp_func() sets the comparison function of B<sk> to B<compar>.
103 The previous comparison function is returned or B<NULL> if there was
104 no previous comparison function.
106 sk_TYPE_free() frees up the B<sk> structure. It does B<not> free up any
107 elements of B<sk>. After this call B<sk> is no longer valid.
109 sk_TYPE_zero() sets the number of elements in B<sk> to zero. It does not free
110 B<sk> so after this call B<sk> is still valid.
112 sk_TYPE_pop_free() frees up all elements of B<sk> and B<sk> itself. The
113 free function freefunc() is called on each element to free it.
115 sk_TYPE_delete() deletes element B<i> from B<sk>. It returns the deleted
116 element or B<NULL> if B<i> is out of range.
118 sk_TYPE_delete_ptr() deletes element matching B<ptr> from B<sk>. It returns
119 the deleted element or B<NULL> if no element matching B<ptr> was found.
121 sk_TYPE_insert() inserts B<ptr> into B<sk> at position B<idx>. Any existing
122 elements at or after B<idx> are moved downwards. If B<idx> is out of range
123 the new element is appended to B<sk>. sk_TYPE_insert() either returns the
124 number of elements in B<sk> after the new element is inserted or zero if
125 an error (such as memory allocation failure) occurred.
127 sk_TYPE_push() appends B<ptr> to B<sk> it is equivalent to:
129 sk_TYPE_insert(sk, ptr, -1);
131 sk_TYPE_unshift() inserts B<ptr> at the start of B<sk> it is equivalent to:
133 sk_TYPE_insert(sk, ptr, 0);
135 sk_TYPE_pop() returns and removes the last element from B<sk>.
137 sk_TYPE_shift() returns and removes the first element from B<sk>.
139 sk_TYPE_set() sets element B<idx> of B<sk> to B<ptr> replacing the current
140 element. The new element value is returned or B<NULL> if an error occurred:
141 this will only happen if B<sk> is B<NULL> or B<idx> is out of range.
143 sk_TYPE_find() searches B<sk> for the element B<ptr>. In the case
144 where no comparison function has been specified, the function performs
145 a linear search for a pointer equal to B<ptr>. The index of the first
146 matching element is returned or B<-1> if there is no match. In the case
147 where a comparison function has been specified, B<sk> is sorted then
148 sk_TYPE_find() returns the index of a matching element or B<-1> if there
149 is no match. Note that, in this case, the matching element returned is
150 not guaranteed to be the first; the comparison function will usually
151 compare the values pointed to rather than the pointers themselves and
152 the order of elements in B<sk> could change.
154 sk_TYPE_find_ex() operates like sk_TYPE_find() except when a comparison
155 function has been specified and no matching element is found. Instead
156 of returning B<-1>, sk_TYPE_find_ex() returns the index of the element
157 either before or after the location where B<ptr> would be if it were
160 sk_TYPE_sort() sorts B<sk> using the supplied comparison function.
162 sk_TYPE_is_sorted() returns B<1> if B<sk> is sorted and B<0> otherwise.
164 sk_TYPE_dup() returns a copy of B<sk>. Note the pointers in the copy
165 are identical to the original.
167 sk_TYPE_deep_copy() returns a new stack where each element has been copied.
168 Copying is performed by the supplied copyfunc() and freeing by freefunc(). The
169 function freefunc() is only called if an error occurs.
173 Care should be taken when accessing stacks in multi-threaded environments.
174 Any operation which increases the size of a stack such as sk_TYPE_insert() or
175 sk_push() can "grow" the size of an internal array and cause race conditions
176 if the same stack is accessed in a different thread. Operations such as
177 sk_find() and sk_sort() can also reorder the stack.
179 Any comparison function supplied should use a metric suitable
180 for use in a binary search operation. That is it should return zero, a
181 positive or negative value if B<a> is equal to, greater than
182 or less than B<b> respectively.
184 Care should be taken when checking the return values of the functions
185 sk_TYPE_find() and sk_TYPE_find_ex(). They return an index to the
186 matching element. In particular B<0> indicates a matching first element.
187 A failed search is indicated by a B<-1> return value.
189 STACK_OF(), DEFINE_STACK_OF(), DEFINE_STACK_OF_CONST(), and
190 DEFINE_SPECIAL_STACK_OF() are implemented as macros.
194 sk_TYPE_num() returns the number of elements in the stack or B<-1> if the
195 passed stack is B<NULL>.
197 sk_TYPE_value() returns a pointer to a stack element or B<NULL> if the
198 index is out of range.
200 sk_TYPE_new() and sk_TYPE_new_null() return an empty stack or B<NULL> if
203 sk_TYPE_set_cmp_func() returns the old comparison function or B<NULL> if
204 there was no old comparison function.
206 sk_TYPE_free(), sk_TYPE_zero(), sk_TYPE_pop_free() and sk_TYPE_sort() do
209 sk_TYPE_pop(), sk_TYPE_shift(), sk_TYPE_delete() and sk_TYPE_delete_ptr()
210 return a pointer to the deleted element or B<NULL> on error.
212 sk_TYPE_insert(), sk_TYPE_push() and sk_TYPE_unshift() return the total
213 number of elements in the stack and 0 if an error occurred.
215 sk_TYPE_set() returns a pointer to the replacement element or B<NULL> on
218 sk_TYPE_find() and sk_TYPE_find_ex() return an index to the found element
221 sk_TYPE_is_sorted() returns B<1> if the stack is sorted and B<0> if it is
224 sk_TYPE_dup() and sk_TYPE_deep_copy() return a pointer to the copy of the
229 Before OpenSSL 1.1.0, this was implemented via macros and not inline functions
230 and was not a public API.
234 Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved.
236 Licensed under the OpenSSL license (the "License"). You may not use
237 this file except in compliance with the License. You can obtain a copy
238 in the file LICENSE in the source distribution or at
239 L<https://www.openssl.org/source/license.html>.