]>
Commit | Line | Data |
---|---|---|
4388f060 A |
1 | /* |
2 | ******************************************************************************* | |
3 | * Copyright (C) 2010-2012, International Business Machines | |
4 | * Corporation and others. All Rights Reserved. | |
5 | ******************************************************************************* | |
6 | * file name: stringtriebuilder.h | |
7 | * encoding: US-ASCII | |
8 | * tab size: 8 (not used) | |
9 | * indentation:4 | |
10 | * | |
11 | * created on: 2010dec24 | |
12 | * created by: Markus W. Scherer | |
13 | */ | |
14 | ||
15 | #ifndef __STRINGTRIEBUILDER_H__ | |
16 | #define __STRINGTRIEBUILDER_H__ | |
17 | ||
18 | #include "unicode/utypes.h" | |
19 | #include "unicode/uobject.h" | |
20 | ||
51004dcb A |
21 | /** |
22 | * \file | |
23 | * \brief C++ API: Builder API for trie builders | |
24 | */ | |
25 | ||
4388f060 A |
26 | // Forward declaration. |
27 | struct UHashtable; | |
28 | typedef struct UHashtable UHashtable; | |
29 | ||
30 | /** | |
31 | * Build options for BytesTrieBuilder and CharsTrieBuilder. | |
32 | * @stable ICU 4.8 | |
33 | */ | |
34 | enum UStringTrieBuildOption { | |
35 | /** | |
36 | * Builds a trie quickly. | |
37 | * @stable ICU 4.8 | |
38 | */ | |
39 | USTRINGTRIE_BUILD_FAST, | |
40 | /** | |
41 | * Builds a trie more slowly, attempting to generate | |
42 | * a shorter but equivalent serialization. | |
43 | * This build option also uses more memory. | |
44 | * | |
45 | * This option can be effective when many integer values are the same | |
46 | * and string/byte sequence suffixes can be shared. | |
47 | * Runtime speed is not expected to improve. | |
48 | * @stable ICU 4.8 | |
49 | */ | |
50 | USTRINGTRIE_BUILD_SMALL | |
51 | }; | |
52 | ||
53 | U_NAMESPACE_BEGIN | |
54 | ||
55 | /** | |
56 | * Base class for string trie builder classes. | |
57 | * | |
58 | * This class is not intended for public subclassing. | |
59 | * @stable ICU 4.8 | |
60 | */ | |
61 | class U_COMMON_API StringTrieBuilder : public UObject { | |
62 | public: | |
63 | #ifndef U_HIDE_INTERNAL_API | |
64 | /** @internal */ | |
65 | static UBool hashNode(const void *node); | |
66 | /** @internal */ | |
67 | static UBool equalNodes(const void *left, const void *right); | |
68 | #endif /* U_HIDE_INTERNAL_API */ | |
69 | ||
70 | protected: | |
71 | // Do not enclose the protected default constructor with #ifndef U_HIDE_INTERNAL_API | |
72 | // or else the compiler will create a public default constructor. | |
73 | /** @internal */ | |
74 | StringTrieBuilder(); | |
75 | /** @internal */ | |
76 | virtual ~StringTrieBuilder(); | |
77 | ||
78 | #ifndef U_HIDE_INTERNAL_API | |
79 | /** @internal */ | |
80 | void createCompactBuilder(int32_t sizeGuess, UErrorCode &errorCode); | |
81 | /** @internal */ | |
82 | void deleteCompactBuilder(); | |
83 | ||
84 | /** @internal */ | |
85 | void build(UStringTrieBuildOption buildOption, int32_t elementsLength, UErrorCode &errorCode); | |
86 | ||
87 | /** @internal */ | |
88 | int32_t writeNode(int32_t start, int32_t limit, int32_t unitIndex); | |
89 | /** @internal */ | |
90 | int32_t writeBranchSubNode(int32_t start, int32_t limit, int32_t unitIndex, int32_t length); | |
91 | #endif /* U_HIDE_INTERNAL_API */ | |
92 | ||
93 | class Node; | |
94 | ||
95 | #ifndef U_HIDE_INTERNAL_API | |
96 | /** @internal */ | |
97 | Node *makeNode(int32_t start, int32_t limit, int32_t unitIndex, UErrorCode &errorCode); | |
98 | /** @internal */ | |
99 | Node *makeBranchSubNode(int32_t start, int32_t limit, int32_t unitIndex, | |
100 | int32_t length, UErrorCode &errorCode); | |
101 | #endif /* U_HIDE_INTERNAL_API */ | |
102 | ||
103 | /** @internal */ | |
104 | virtual int32_t getElementStringLength(int32_t i) const = 0; | |
105 | /** @internal */ | |
106 | virtual UChar getElementUnit(int32_t i, int32_t unitIndex) const = 0; | |
107 | /** @internal */ | |
108 | virtual int32_t getElementValue(int32_t i) const = 0; | |
109 | ||
110 | // Finds the first unit index after this one where | |
111 | // the first and last element have different units again. | |
112 | /** @internal */ | |
113 | virtual int32_t getLimitOfLinearMatch(int32_t first, int32_t last, int32_t unitIndex) const = 0; | |
114 | ||
115 | // Number of different units at unitIndex. | |
116 | /** @internal */ | |
117 | virtual int32_t countElementUnits(int32_t start, int32_t limit, int32_t unitIndex) const = 0; | |
118 | /** @internal */ | |
119 | virtual int32_t skipElementsBySomeUnits(int32_t i, int32_t unitIndex, int32_t count) const = 0; | |
120 | /** @internal */ | |
121 | virtual int32_t indexOfElementWithNextUnit(int32_t i, int32_t unitIndex, UChar unit) const = 0; | |
122 | ||
123 | /** @internal */ | |
124 | virtual UBool matchNodesCanHaveValues() const = 0; | |
125 | ||
126 | /** @internal */ | |
127 | virtual int32_t getMaxBranchLinearSubNodeLength() const = 0; | |
128 | /** @internal */ | |
129 | virtual int32_t getMinLinearMatch() const = 0; | |
130 | /** @internal */ | |
131 | virtual int32_t getMaxLinearMatchLength() const = 0; | |
132 | ||
133 | #ifndef U_HIDE_INTERNAL_API | |
134 | // max(BytesTrie::kMaxBranchLinearSubNodeLength, UCharsTrie::kMaxBranchLinearSubNodeLength). | |
135 | /** @internal */ | |
136 | static const int32_t kMaxBranchLinearSubNodeLength=5; | |
137 | ||
138 | // Maximum number of nested split-branch levels for a branch on all 2^16 possible UChar units. | |
139 | // log2(2^16/kMaxBranchLinearSubNodeLength) rounded up. | |
140 | /** @internal */ | |
141 | static const int32_t kMaxSplitBranchLevels=14; | |
142 | ||
143 | /** | |
144 | * Makes sure that there is only one unique node registered that is | |
145 | * equivalent to newNode. | |
146 | * @param newNode Input node. The builder takes ownership. | |
147 | * @param errorCode ICU in/out UErrorCode. | |
148 | Set to U_MEMORY_ALLOCATION_ERROR if it was success but newNode==NULL. | |
149 | * @return newNode if it is the first of its kind, or | |
150 | * an equivalent node if newNode is a duplicate. | |
151 | * @internal | |
152 | */ | |
153 | Node *registerNode(Node *newNode, UErrorCode &errorCode); | |
154 | /** | |
155 | * Makes sure that there is only one unique FinalValueNode registered | |
156 | * with this value. | |
157 | * Avoids creating a node if the value is a duplicate. | |
158 | * @param value A final value. | |
159 | * @param errorCode ICU in/out UErrorCode. | |
160 | Set to U_MEMORY_ALLOCATION_ERROR if it was success but newNode==NULL. | |
161 | * @return A FinalValueNode with the given value. | |
162 | * @internal | |
163 | */ | |
164 | Node *registerFinalValue(int32_t value, UErrorCode &errorCode); | |
165 | ||
166 | /* | |
167 | * C++ note: | |
168 | * registerNode() and registerFinalValue() take ownership of their input nodes, | |
169 | * and only return owned nodes. | |
170 | * If they see a failure UErrorCode, they will delete the input node. | |
171 | * If they get a NULL pointer, they will record a U_MEMORY_ALLOCATION_ERROR. | |
172 | * If there is a failure, they return NULL. | |
173 | * | |
174 | * NULL Node pointers can be safely passed into other Nodes because | |
175 | * they call the static Node::hashCode() which checks for a NULL pointer first. | |
176 | * | |
177 | * Therefore, as long as builder functions register a new node, | |
178 | * they need to check for failures only before explicitly dereferencing | |
179 | * a Node pointer, or before setting a new UErrorCode. | |
180 | */ | |
181 | ||
182 | // Hash set of nodes, maps from nodes to integer 1. | |
183 | /** @internal */ | |
184 | UHashtable *nodes; | |
185 | ||
186 | /** @internal */ | |
187 | class Node : public UObject { | |
188 | public: | |
189 | Node(int32_t initialHash) : hash(initialHash), offset(0) {} | |
190 | inline int32_t hashCode() const { return hash; } | |
191 | // Handles node==NULL. | |
192 | static inline int32_t hashCode(const Node *node) { return node==NULL ? 0 : node->hashCode(); } | |
193 | // Base class operator==() compares the actual class types. | |
194 | virtual UBool operator==(const Node &other) const; | |
195 | inline UBool operator!=(const Node &other) const { return !operator==(other); } | |
196 | /** | |
197 | * Traverses the Node graph and numbers branch edges, with rightmost edges first. | |
198 | * This is to avoid writing a duplicate node twice. | |
199 | * | |
200 | * Branch nodes in this trie data structure are not symmetric. | |
201 | * Most branch edges "jump" to other nodes but the rightmost branch edges | |
202 | * just continue without a jump. | |
203 | * Therefore, write() must write the rightmost branch edge last | |
204 | * (trie units are written backwards), and must write it at that point even if | |
205 | * it is a duplicate of a node previously written elsewhere. | |
206 | * | |
207 | * This function visits and marks right branch edges first. | |
208 | * Edges are numbered with increasingly negative values because we share the | |
209 | * offset field which gets positive values when nodes are written. | |
210 | * A branch edge also remembers the first number for any of its edges. | |
211 | * | |
212 | * When a further-left branch edge has a number in the range of the rightmost | |
213 | * edge's numbers, then it will be written as part of the required right edge | |
214 | * and we can avoid writing it first. | |
215 | * | |
216 | * After root.markRightEdgesFirst(-1) the offsets of all nodes are negative | |
217 | * edge numbers. | |
218 | * | |
219 | * @param edgeNumber The first edge number for this node and its sub-nodes. | |
220 | * @return An edge number that is at least the maximum-negative | |
221 | * of the input edge number and the numbers of this node and all of its sub-nodes. | |
222 | */ | |
223 | virtual int32_t markRightEdgesFirst(int32_t edgeNumber); | |
224 | // write() must set the offset to a positive value. | |
225 | virtual void write(StringTrieBuilder &builder) = 0; | |
226 | // See markRightEdgesFirst. | |
227 | inline void writeUnlessInsideRightEdge(int32_t firstRight, int32_t lastRight, | |
228 | StringTrieBuilder &builder) { | |
229 | // Note: Edge numbers are negative, lastRight<=firstRight. | |
230 | // If offset>0 then this node and its sub-nodes have been written already | |
231 | // and we need not write them again. | |
232 | // If this node is part of the unwritten right branch edge, | |
233 | // then we wait until that is written. | |
234 | if(offset<0 && (offset<lastRight || firstRight<offset)) { | |
235 | write(builder); | |
236 | } | |
237 | } | |
238 | inline int32_t getOffset() const { return offset; } | |
239 | protected: | |
240 | int32_t hash; | |
241 | int32_t offset; | |
4388f060 A |
242 | }; |
243 | ||
244 | // This class should not be overridden because | |
245 | // registerFinalValue() compares a stack-allocated FinalValueNode | |
246 | // (stack-allocated so that we don't unnecessarily create lots of duplicate nodes) | |
247 | // with the input node, and the | |
248 | // !Node::operator==(other) used inside FinalValueNode::operator==(other) | |
249 | // will be false if the typeid's are different. | |
250 | /** @internal */ | |
251 | class FinalValueNode : public Node { | |
252 | public: | |
253 | FinalValueNode(int32_t v) : Node(0x111111*37+v), value(v) {} | |
254 | virtual UBool operator==(const Node &other) const; | |
255 | virtual void write(StringTrieBuilder &builder); | |
256 | protected: | |
257 | int32_t value; | |
258 | }; | |
259 | ||
51004dcb A |
260 | /** |
261 | * @internal | |
262 | */ | |
4388f060 A |
263 | class ValueNode : public Node { |
264 | public: | |
265 | ValueNode(int32_t initialHash) : Node(initialHash), hasValue(FALSE), value(0) {} | |
266 | virtual UBool operator==(const Node &other) const; | |
267 | void setValue(int32_t v) { | |
268 | hasValue=TRUE; | |
269 | value=v; | |
270 | hash=hash*37+v; | |
271 | } | |
272 | protected: | |
273 | UBool hasValue; | |
274 | int32_t value; | |
275 | }; | |
276 | ||
51004dcb A |
277 | /** |
278 | * @internal | |
279 | */ | |
4388f060 A |
280 | class IntermediateValueNode : public ValueNode { |
281 | public: | |
282 | IntermediateValueNode(int32_t v, Node *nextNode) | |
283 | : ValueNode(0x222222*37+hashCode(nextNode)), next(nextNode) { setValue(v); } | |
284 | virtual UBool operator==(const Node &other) const; | |
285 | virtual int32_t markRightEdgesFirst(int32_t edgeNumber); | |
286 | virtual void write(StringTrieBuilder &builder); | |
287 | protected: | |
288 | Node *next; | |
289 | }; | |
290 | ||
51004dcb A |
291 | /** |
292 | * @internal | |
293 | */ | |
4388f060 A |
294 | class LinearMatchNode : public ValueNode { |
295 | public: | |
296 | LinearMatchNode(int32_t len, Node *nextNode) | |
297 | : ValueNode((0x333333*37+len)*37+hashCode(nextNode)), | |
298 | length(len), next(nextNode) {} | |
299 | virtual UBool operator==(const Node &other) const; | |
300 | virtual int32_t markRightEdgesFirst(int32_t edgeNumber); | |
301 | protected: | |
302 | int32_t length; | |
303 | Node *next; | |
304 | }; | |
305 | ||
51004dcb A |
306 | /** |
307 | * @internal | |
308 | */ | |
4388f060 A |
309 | class BranchNode : public Node { |
310 | public: | |
311 | BranchNode(int32_t initialHash) : Node(initialHash) {} | |
312 | protected: | |
313 | int32_t firstEdgeNumber; | |
314 | }; | |
315 | ||
51004dcb A |
316 | /** |
317 | * @internal | |
318 | */ | |
4388f060 A |
319 | class ListBranchNode : public BranchNode { |
320 | public: | |
321 | ListBranchNode() : BranchNode(0x444444), length(0) {} | |
322 | virtual UBool operator==(const Node &other) const; | |
323 | virtual int32_t markRightEdgesFirst(int32_t edgeNumber); | |
324 | virtual void write(StringTrieBuilder &builder); | |
325 | // Adds a unit with a final value. | |
326 | void add(int32_t c, int32_t value) { | |
327 | units[length]=(UChar)c; | |
328 | equal[length]=NULL; | |
329 | values[length]=value; | |
330 | ++length; | |
331 | hash=(hash*37+c)*37+value; | |
332 | } | |
333 | // Adds a unit which leads to another match node. | |
334 | void add(int32_t c, Node *node) { | |
335 | units[length]=(UChar)c; | |
336 | equal[length]=node; | |
337 | values[length]=0; | |
338 | ++length; | |
339 | hash=(hash*37+c)*37+hashCode(node); | |
340 | } | |
341 | protected: | |
342 | Node *equal[kMaxBranchLinearSubNodeLength]; // NULL means "has final value". | |
343 | int32_t length; | |
344 | int32_t values[kMaxBranchLinearSubNodeLength]; | |
345 | UChar units[kMaxBranchLinearSubNodeLength]; | |
346 | }; | |
347 | ||
51004dcb A |
348 | /** |
349 | * @internal | |
350 | */ | |
4388f060 A |
351 | class SplitBranchNode : public BranchNode { |
352 | public: | |
353 | SplitBranchNode(UChar middleUnit, Node *lessThanNode, Node *greaterOrEqualNode) | |
354 | : BranchNode(((0x555555*37+middleUnit)*37+ | |
355 | hashCode(lessThanNode))*37+hashCode(greaterOrEqualNode)), | |
356 | unit(middleUnit), lessThan(lessThanNode), greaterOrEqual(greaterOrEqualNode) {} | |
357 | virtual UBool operator==(const Node &other) const; | |
358 | virtual int32_t markRightEdgesFirst(int32_t edgeNumber); | |
359 | virtual void write(StringTrieBuilder &builder); | |
360 | protected: | |
361 | UChar unit; | |
362 | Node *lessThan; | |
363 | Node *greaterOrEqual; | |
364 | }; | |
365 | ||
366 | // Branch head node, for writing the actual node lead unit. | |
367 | /** @internal */ | |
368 | class BranchHeadNode : public ValueNode { | |
369 | public: | |
370 | BranchHeadNode(int32_t len, Node *subNode) | |
371 | : ValueNode((0x666666*37+len)*37+hashCode(subNode)), | |
372 | length(len), next(subNode) {} | |
373 | virtual UBool operator==(const Node &other) const; | |
374 | virtual int32_t markRightEdgesFirst(int32_t edgeNumber); | |
375 | virtual void write(StringTrieBuilder &builder); | |
376 | protected: | |
377 | int32_t length; | |
378 | Node *next; // A branch sub-node. | |
379 | }; | |
380 | #endif /* U_HIDE_INTERNAL_API */ | |
381 | ||
382 | /** @internal */ | |
383 | virtual Node *createLinearMatchNode(int32_t i, int32_t unitIndex, int32_t length, | |
384 | Node *nextNode) const = 0; | |
385 | ||
386 | /** @internal */ | |
387 | virtual int32_t write(int32_t unit) = 0; | |
388 | /** @internal */ | |
389 | virtual int32_t writeElementUnits(int32_t i, int32_t unitIndex, int32_t length) = 0; | |
390 | /** @internal */ | |
391 | virtual int32_t writeValueAndFinal(int32_t i, UBool isFinal) = 0; | |
392 | /** @internal */ | |
393 | virtual int32_t writeValueAndType(UBool hasValue, int32_t value, int32_t node) = 0; | |
394 | /** @internal */ | |
395 | virtual int32_t writeDeltaTo(int32_t jumpTarget) = 0; | |
4388f060 A |
396 | }; |
397 | ||
398 | U_NAMESPACE_END | |
399 | ||
400 | #endif // __STRINGTRIEBUILDER_H__ |