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