xref: /freebsd/crypto/openssl/doc/internal/man3/ossl_namemap_new.pod (revision ba3c1f5972d7b90feb6e6da47905ff2757e0fe57)
1=pod
2
3=head1 NAME
4
5ossl_namemap_new, ossl_namemap_free, ossl_namemap_stored, ossl_namemap_empty,
6ossl_namemap_add_name, ossl_namemap_add_name_n, ossl_namemap_add_names,
7ossl_namemap_name2num, ossl_namemap_name2num_n,
8ossl_namemap_doall_names
9- internal number E<lt>-E<gt> name map
10
11=head1 SYNOPSIS
12
13 #include "internal/cryptlib.h"
14
15 OSSL_NAMEMAP *ossl_namemap_stored(OSSL_LIB_CTX *libctx);
16
17 OSSL_NAMEMAP *ossl_namemap_new(void);
18 void ossl_namemap_free(OSSL_NAMEMAP *namemap);
19 int ossl_namemap_empty(OSSL_NAMEMAP *namemap);
20
21 int ossl_namemap_add_name(OSSL_NAMEMAP *namemap, int number, const char *name);
22 int ossl_namemap_add_name_n(OSSL_NAMEMAP *namemap, int number,
23                             const char *name, size_t name_len);
24
25 int ossl_namemap_name2num(const OSSL_NAMEMAP *namemap, const char *name);
26 int ossl_namemap_name2num_n(const OSSL_NAMEMAP *namemap,
27                             const char *name, size_t name_len);
28 int ossl_namemap_doall_names(const OSSL_NAMEMAP *namemap, int number,
29                              void (*fn)(const char *name, void *data),
30                              void *data);
31
32 int ossl_namemap_add_names(OSSL_NAMEMAP *namemap, int number,
33                            const char *names, const char separator);
34
35=head1 DESCRIPTION
36
37A B<OSSL_NAMEMAP> is a one-to-many number E<lt>-E<gt> names map, which
38can be used to give any arbitrary set of names (any string) a unique
39dynamic identity that is valid throughout the lifetime of the associated
40library context.
41
42ossl_namemap_new() and ossl_namemap_free() construct and destruct a
43new B<OSSL_NAMEMAP>.
44This is suitable to use when the B<OSSL_NAMEMAP> is embedded in other
45structures, or should be independent for any reason.
46
47ossl_namemap_empty() checks if the given B<OSSL_NAMEMAP> is empty or
48not.
49
50ossl_namemap_stored() finds or auto-creates the default namemap in the
51given library context.
52The returned B<OSSL_NAMEMAP> can't be destructed using
53ossl_namemap_free().
54
55ossl_namemap_add_name() adds a new name to the namemap if it's not already
56present.
57If the given I<number> is zero, a new number will be allocated to
58identify this I<name>.
59If the given I<number> is nonzero, the I<name> is added to the set of
60names already associated with that number.
61
62ossl_namemap_name2num() finds the number corresponding to the given
63I<name>.
64
65ossl_namemap_add_name_n() and ossl_namemap_name2num_n() do the same thing
66as ossl_namemap_add_name() and ossl_namemap_name2num(), but take a string
67length I<name_len> as well, allowing the caller to use a fragment of
68a string as a name.
69
70ossl_namemap_doall_names() walks through all names associated with
71I<number> in the given I<namemap> and calls the function I<fn> for
72each of them.
73I<fn> is also passed the I<data> argument, which allows any caller to
74pass extra data for that function to use.
75
76ossl_namemap_add_names() divides up a set of names given in I<names>,
77separated by I<separator>, and adds each to the I<namemap>, all with
78the same number.  If some of them already exist in the I<namemap>,
79they must all have the same associated number, which will be adopted
80for any name that doesn't exist yet.
81
82=head1 RETURN VALUES
83
84ossl_namemap_new() and ossl_namemap_stored() return the pointer to a
85B<OSSL_NAMEMAP>, or NULL on error.
86
87ossl_namemap_empty() returns 1 if the B<OSSL_NAMEMAP> is NULL or
88empty, 0 if it's not empty, or -1 on internal error (such as inability
89to lock).
90
91ossl_namemap_add_name() and ossl_namemap_add_name_n() return the number
92associated with the added string, or zero on error.
93
94ossl_namemap_num2names() returns a pointer to a NULL-terminated list of
95pointers to the names corresponding to the given number, or NULL if
96it's undefined in the given B<OSSL_NAMEMAP>.
97
98ossl_namemap_name2num() and ossl_namemap_name2num_n() return the number
99corresponding to the given name, or 0 if it's undefined in the given
100B<OSSL_NAMEMAP>.
101
102ossl_namemap_doall_names() returns 1 if the callback was called for all names. A
103return value of 0 means that the callback was not called for any names.
104
105ossl_namemap_add_names() returns the number associated with the added
106names, or zero on error.
107
108=head1 NOTES
109
110The result from ossl_namemap_num2names() isn't thread safe, other threads
111dealing with the same namemap may cause the list of names to change
112location.
113It is therefore strongly recommended to only use the result in code
114guarded by a thread lock.
115
116=head1 HISTORY
117
118The functions described here were all added in OpenSSL 3.0.
119
120=head1 COPYRIGHT
121
122Copyright 2019-2021 The OpenSSL Project Authors. All Rights Reserved.
123
124Licensed under the Apache License 2.0 (the "License").  You may not use
125this file except in compliance with the License.  You can obtain a copy
126in the file LICENSE in the source distribution or at
127L<https://www.openssl.org/source/license.html>.
128
129=cut
130