xref: /openbsd/lib/libcbor/src/cbor/strings.h (revision 274d7c50)
1 /*
2  * Copyright (c) 2014-2017 Pavel Kalvoda <me@pavelkalvoda.com>
3  *
4  * libcbor is free software; you can redistribute it and/or modify
5  * it under the terms of the MIT license. See LICENSE for details.
6  */
7 
8 #ifndef LIBCBOR_STRINGS_H
9 #define LIBCBOR_STRINGS_H
10 
11 #include "cbor/common.h"
12 
13 #ifdef __cplusplus
14 extern "C" {
15 #endif
16 
17 /*
18 * ============================================================================
19 * String manipulation
20 * ============================================================================
21 */
22 
23 /** Returns the length of the underlying string
24  *
25  * For definite strings only
26  *
27  * @param item[borrow] a definite string
28  * @return length of the string. Zero if no chunk has been attached yet
29  */
30 size_t cbor_string_length(const cbor_item_t *item);
31 
32 /** The number of codepoints in this string
33  *
34  * Might differ from length if there are multibyte ones
35  *
36  * @param item[borrow] A string
37  * @return The number of codepoints in this string
38  */
39 size_t cbor_string_codepoint_count(const cbor_item_t *item);
40 
41 /** Is the string definite?
42  *
43  * @param item[borrow] a string
44  * @return Is the string definite?
45  */
46 bool cbor_string_is_definite(const cbor_item_t *item);
47 
48 /** Is the string indefinite?
49  *
50  * @param item[borrow] a string
51  * @return Is the string indefinite?
52  */
53 bool cbor_string_is_indefinite(const cbor_item_t *item);
54 
55 /** Get the handle to the underlying string
56  *
57  * Definite items only. Modifying the data is allowed. In that case, the caller takes
58  * responsibility for the effect on items this item might be a part of
59  *
60  * @param item[borrow] A definite string
61  * @return The address of the underlying string. `NULL` if no data have been assigned yet.
62  */
63 cbor_mutable_data cbor_string_handle(const cbor_item_t *item);
64 
65 /** Set the handle to the underlying string
66  *
67  *
68  * \rst
69  * .. warning:: Using a pointer to a stack allocated constant is a common mistake. Lifetime of the string will expire when it goes out of scope and the CBOR item will be left inconsistent.
70  * \endrst
71  *
72  * @param item[borrow] A definite string
73  * @param data The memory block. The caller gives up the ownership of the block. libcbor will deallocate it when appropriate using its free function
74  * @param length Length of the data block
75  */
76 void cbor_string_set_handle(cbor_item_t *item, cbor_mutable_data CBOR_RESTRICT_POINTER data, size_t length);
77 
78 /** Get the handle to the array of chunks
79  *
80  * Manipulations with the memory block (e.g. sorting it) are allowed, but the validity and the number of chunks must be retained.
81  *
82  * @param item[borrow] A indefinite string
83  * @return array of #cbor_string_chunk_count definite strings
84  */
85 cbor_item_t **cbor_string_chunks_handle(const cbor_item_t *item);
86 
87 /** Get the number of chunks this string consist of
88  *
89  * @param item[borrow] A indefinite string
90  * @return The chunk count. 0 for freshly created items.
91  */
92 size_t cbor_string_chunk_count(const cbor_item_t *item);
93 
94 /** Appends a chunk to the string
95  *
96  * Indefinite strings only.
97  *
98  * May realloc the chunk storage.
99  *
100  * @param item[borrow] An indefinite string
101  * @param item[incref] A definite string
102  * @return true on success. false on realloc failure. In that case, the refcount of `chunk` is not increased and the `item` is left intact.
103  */
104 bool cbor_string_add_chunk(cbor_item_t *item, cbor_item_t *chunk);
105 
106 /** Creates a new definite string
107  *
108  * The handle is initialized to `NULL` and length to 0
109  *
110  * @return **new** definite string. `NULL` on malloc failure.
111  */
112 cbor_item_t *cbor_new_definite_string();
113 
114 /** Creates a new indefinite string
115  *
116  * The chunks array is initialized to `NULL` and chunkcount to 0
117  *
118  * @return **new** indefinite string. `NULL` on malloc failure.
119  */
120 cbor_item_t *cbor_new_indefinite_string();
121 
122 /** Creates a new string and initializes it
123  *
124  * The `val` will be copied to a newly allocated block
125  *
126  * @param val A null-terminated UTF-8 string
127  * @return A **new** string with content `handle`. `NULL` on malloc failure.
128  */
129 cbor_item_t *cbor_build_string(const char *val);
130 
131 /** Creates a new string and initializes it
132  *
133  * The `handle` will be copied to a newly allocated block
134  *
135  * @param val A UTF-8 string, at least \p length long (excluding the null byte)
136  * @return A **new** string with content `handle`. `NULL` on malloc failure.
137  */
138 cbor_item_t *cbor_build_stringn(const char *val, size_t length);
139 
140 #ifdef __cplusplus
141 }
142 #endif
143 
144 #endif //LIBCBOR_STRINGS_H
145