1// © 2017 and later: Unicode, Inc. and others.
2// License & terms of use: http://www.unicode.org/copyright.html
3
4// umutablecptrie.h (split out of ucptrie.h)
5// created: 2018jan24 Markus W. Scherer
6
7#ifndef __UMUTABLECPTRIE_H__
8#define __UMUTABLECPTRIE_H__
9
10#include "unicode/utypes.h"
11
12#include "unicode/ucpmap.h"
13#include "unicode/ucptrie.h"
14#include "unicode/utf8.h"
15
16#if U_SHOW_CPLUSPLUS_API
17#include "unicode/localpointer.h"
18#endif // U_SHOW_CPLUSPLUS_API
19
20U_CDECL_BEGIN
21
22/**
23 * \file
24 * \brief C API: This file defines a mutable Unicode code point trie.
25 *
26 * @see UCPTrie
27 * @see UMutableCPTrie
28 */
29
30/**
31 * Mutable Unicode code point trie.
32 * Fast map from Unicode code points (U+0000..U+10FFFF) to 32-bit integer values.
33 * For details see https://icu.unicode.org/design/struct/utrie
34 *
35 * Setting values (especially ranges) and lookup is fast.
36 * The mutable trie is only somewhat space-efficient.
37 * It builds a compacted, immutable UCPTrie.
38 *
39 * This trie can be modified while iterating over its contents.
40 * For example, it is possible to merge its values with those from another
41 * set of ranges (e.g., another mutable or immutable trie):
42 * Iterate over those source ranges; for each of them iterate over this trie;
43 * add the source value into the value of each trie range.
44 *
45 * @see UCPTrie
46 * @see umutablecptrie_buildImmutable
47 * @stable ICU 63
48 */
49typedef struct UMutableCPTrie UMutableCPTrie;
50
51/**
52 * Creates a mutable trie that initially maps each Unicode code point to the same value.
53 * It uses 32-bit data values until umutablecptrie_buildImmutable() is called.
54 * umutablecptrie_buildImmutable() takes a valueWidth parameter which
55 * determines the number of bits in the data value in the resulting UCPTrie.
56 * You must umutablecptrie_close() the trie once you are done using it.
57 *
58 * @param initialValue the initial value that is set for all code points
59 * @param errorValue the value for out-of-range code points and ill-formed UTF-8/16
60 * @param pErrorCode an in/out ICU UErrorCode
61 * @return the trie
62 * @stable ICU 63
63 */
64U_CAPI UMutableCPTrie * U_EXPORT2
65umutablecptrie_open(uint32_t initialValue, uint32_t errorValue, UErrorCode *pErrorCode);
66
67/**
68 * Clones a mutable trie.
69 * You must umutablecptrie_close() the clone once you are done using it.
70 *
71 * @param other the trie to clone
72 * @param pErrorCode an in/out ICU UErrorCode
73 * @return the trie clone
74 * @stable ICU 63
75 */
76U_CAPI UMutableCPTrie * U_EXPORT2
77umutablecptrie_clone(const UMutableCPTrie *other, UErrorCode *pErrorCode);
78
79/**
80 * Closes a mutable trie and releases associated memory.
81 *
82 * @param trie the trie
83 * @stable ICU 63
84 */
85U_CAPI void U_EXPORT2
86umutablecptrie_close(UMutableCPTrie *trie);
87
88/**
89 * Creates a mutable trie with the same contents as the UCPMap.
90 * You must umutablecptrie_close() the mutable trie once you are done using it.
91 *
92 * @param map the source map
93 * @param pErrorCode an in/out ICU UErrorCode
94 * @return the mutable trie
95 * @stable ICU 63
96 */
97U_CAPI UMutableCPTrie * U_EXPORT2
98umutablecptrie_fromUCPMap(const UCPMap *map, UErrorCode *pErrorCode);
99
100/**
101 * Creates a mutable trie with the same contents as the immutable one.
102 * You must umutablecptrie_close() the mutable trie once you are done using it.
103 *
104 * @param trie the immutable trie
105 * @param pErrorCode an in/out ICU UErrorCode
106 * @return the mutable trie
107 * @stable ICU 63
108 */
109U_CAPI UMutableCPTrie * U_EXPORT2
110umutablecptrie_fromUCPTrie(const UCPTrie *trie, UErrorCode *pErrorCode);
111
112/**
113 * Returns the value for a code point as stored in the trie.
114 *
115 * @param trie the trie
116 * @param c the code point
117 * @return the value
118 * @stable ICU 63
119 */
120U_CAPI uint32_t U_EXPORT2
121umutablecptrie_get(const UMutableCPTrie *trie, UChar32 c);
122
123/**
124 * Returns the last code point such that all those from start to there have the same value.
125 * Can be used to efficiently iterate over all same-value ranges in a trie.
126 * (This is normally faster than iterating over code points and get()ting each value,
127 * but much slower than a data structure that stores ranges directly.)
128 *
129 * The trie can be modified between calls to this function.
130 *
131 * If the UCPMapValueFilter function pointer is not NULL, then
132 * the value to be delivered is passed through that function, and the return value is the end
133 * of the range where all values are modified to the same actual value.
134 * The value is unchanged if that function pointer is NULL.
135 *
136 * See the same-signature ucptrie_getRange() for a code sample.
137 *
138 * @param trie the trie
139 * @param start range start
140 * @param option defines whether surrogates are treated normally,
141 * or as having the surrogateValue; usually UCPMAP_RANGE_NORMAL
142 * @param surrogateValue value for surrogates; ignored if option==UCPMAP_RANGE_NORMAL
143 * @param filter a pointer to a function that may modify the trie data value,
144 * or NULL if the values from the trie are to be used unmodified
145 * @param context an opaque pointer that is passed on to the filter function
146 * @param pValue if not NULL, receives the value that every code point start..end has;
147 * may have been modified by filter(context, trie value)
148 * if that function pointer is not NULL
149 * @return the range end code point, or -1 if start is not a valid code point
150 * @stable ICU 63
151 */
152U_CAPI UChar32 U_EXPORT2
153umutablecptrie_getRange(const UMutableCPTrie *trie, UChar32 start,
154 UCPMapRangeOption option, uint32_t surrogateValue,
155 UCPMapValueFilter *filter, const void *context, uint32_t *pValue);
156
157/**
158 * Sets a value for a code point.
159 *
160 * @param trie the trie
161 * @param c the code point
162 * @param value the value
163 * @param pErrorCode an in/out ICU UErrorCode
164 * @stable ICU 63
165 */
166U_CAPI void U_EXPORT2
167umutablecptrie_set(UMutableCPTrie *trie, UChar32 c, uint32_t value, UErrorCode *pErrorCode);
168
169/**
170 * Sets a value for each code point [start..end].
171 * Faster and more space-efficient than setting the value for each code point separately.
172 *
173 * @param trie the trie
174 * @param start the first code point to get the value
175 * @param end the last code point to get the value (inclusive)
176 * @param value the value
177 * @param pErrorCode an in/out ICU UErrorCode
178 * @stable ICU 63
179 */
180U_CAPI void U_EXPORT2
181umutablecptrie_setRange(UMutableCPTrie *trie,
182 UChar32 start, UChar32 end,
183 uint32_t value, UErrorCode *pErrorCode);
184
185/**
186 * Compacts the data and builds an immutable UCPTrie according to the parameters.
187 * After this, the mutable trie will be empty.
188 *
189 * The mutable trie stores 32-bit values until buildImmutable() is called.
190 * If values shorter than 32 bits are to be stored in the immutable trie,
191 * then the upper bits are discarded.
192 * For example, when the mutable trie contains values 0x81, -0x7f, and 0xa581,
193 * and the value width is 8 bits, then each of these is stored as 0x81
194 * and the immutable trie will return that as an unsigned value.
195 * (Some implementations may want to make productive temporary use of the upper bits
196 * until buildImmutable() discards them.)
197 *
198 * Not every possible set of mappings can be built into a UCPTrie,
199 * because of limitations resulting from speed and space optimizations.
200 * Every Unicode assigned character can be mapped to a unique value.
201 * Typical data yields data structures far smaller than the limitations.
202 *
203 * It is possible to construct extremely unusual mappings that exceed the data structure limits.
204 * In such a case this function will fail with a U_INDEX_OUTOFBOUNDS_ERROR.
205 *
206 * @param trie the trie trie
207 * @param type selects the trie type
208 * @param valueWidth selects the number of bits in a trie data value; if smaller than 32 bits,
209 * then the values stored in the trie will be truncated first
210 * @param pErrorCode an in/out ICU UErrorCode
211 *
212 * @see umutablecptrie_fromUCPTrie
213 * @stable ICU 63
214 */
215U_CAPI UCPTrie * U_EXPORT2
216umutablecptrie_buildImmutable(UMutableCPTrie *trie, UCPTrieType type, UCPTrieValueWidth valueWidth,
217 UErrorCode *pErrorCode);
218
219U_CDECL_END
220
221#if U_SHOW_CPLUSPLUS_API
222
223U_NAMESPACE_BEGIN
224
225/**
226 * \class LocalUMutableCPTriePointer
227 * "Smart pointer" class, closes a UMutableCPTrie via umutablecptrie_close().
228 * For most methods see the LocalPointerBase base class.
229 *
230 * @see LocalPointerBase
231 * @see LocalPointer
232 * @stable ICU 63
233 */
234U_DEFINE_LOCAL_OPEN_POINTER(LocalUMutableCPTriePointer, UMutableCPTrie, umutablecptrie_close);
235
236U_NAMESPACE_END
237
238#endif
239
240#endif
241