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() and sk_TYPE_find_ex() search B<sk> using the supplied
144 comparison function for an element matching B<ptr>. sk_TYPE_find() returns
145 the index of the first matching element or B<-1> if there is no match.
146 sk_TYPE_find_ex() returns a matching element or the nearest element that
147 does not match B<ptr>. Note: if a comparison function is set then B<sk> is
148 sorted before the search which may change its order. If no comparison
149 function is set then a linear search is made for a pointer matching B<ptr>
150 and the stack is not reordered.
152 sk_TYPE_sort() sorts B<sk> using the supplied comparison function.
154 sk_TYPE_is_sorted() returns B<1> if B<sk> is sorted and B<0> otherwise.
156 sk_TYPE_dup() returns a copy of B<sk>. Note the pointers in the copy
157 are identical to the original.
159 sk_TYPE_deep_copy() returns a new stack where each element has been copied.
160 Copying is performed by the supplied copyfunc() and freeing by freefunc(). The
161 function freefunc() is only called if an error occurs.
165 Care should be taken when accessing stacks in multi-threaded environments.
166 Any operation which increases the size of a stack such as sk_TYPE_insert() or
167 sk_push() can "grow" the size of an internal array and cause race conditions
168 if the same stack is accessed in a different thread. Operations such as
169 sk_find() and sk_sort() can also reorder the stack.
171 Any comparison function supplied should use a metric suitable
172 for use in a binary search operation. That is it should return zero, a
173 positive or negative value if B<a> is equal to, greater than
174 or less than B<b> respectively.
176 Care should be taken when checking the return values of the functions
177 sk_TYPE_find() and sk_TYPE_find_ex(). They return an index to the
178 matching element. In particular B<0> indicates a matching first element.
179 A failed search is indicated by a B<-1> return value.
181 STACK_OF(), DEFINE_STACK_OF(), DEFINE_STACK_OF_CONST(), and
182 DEFINE_SPECIAL_STACK_OF() are implemented as macros.
186 sk_TYPE_num() returns the number of elements in the stack or B<-1> if the
187 passed stack is B<NULL>.
189 sk_TYPE_value() returns a pointer to a stack element or B<NULL> if the
190 index is out of range.
192 sk_TYPE_new() and sk_TYPE_new_null() return an empty stack or B<NULL> if
195 sk_TYPE_set_cmp_func() returns the old comparison function or B<NULL> if
196 there was no old comparison function.
198 sk_TYPE_free(), sk_TYPE_zero(), sk_TYPE_pop_free() and sk_TYPE_sort() do
201 sk_TYPE_pop(), sk_TYPE_shift(), sk_TYPE_delete() and sk_TYPE_delete_ptr()
202 return a pointer to the deleted element or B<NULL> on error.
204 sk_TYPE_insert(), sk_TYPE_push() and sk_TYPE_unshift() return the total
205 number of elements in the stack and 0 if an error occurred.
207 sk_TYPE_set() returns a pointer to the replacement element or B<NULL> on
210 sk_TYPE_find() and sk_TYPE_find_ex() return an index to the found element
213 sk_TYPE_is_sorted() returns B<1> if the stack is sorted and B<0> if it is
216 sk_TYPE_dup() and sk_TYPE_deep_copy() return a pointer to the copy of the
221 Before OpenSSL 1.1.0, this was implemented via macros and not inline functions
222 and was not a public API.
226 Copyright 2000-2016 The OpenSSL Project Authors. All Rights Reserved.
228 Licensed under the OpenSSL license (the "License"). You may not use
229 this file except in compliance with the License. You can obtain a copy
230 in the file LICENSE in the source distribution or at
231 L<https://www.openssl.org/source/license.html>.