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stringtriebuilder.h
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1 // Copyright (C) 2016 and later: Unicode, Inc. and others.
2 // License & terms of use: http://www.unicode.org/copyright.html
3 /*
4 *******************************************************************************
5 * Copyright (C) 2010-2012,2014, International Business Machines
6 * Corporation and others. All Rights Reserved.
7 *******************************************************************************
8 * file name: stringtriebuilder.h
9 * encoding: US-ASCII
10 * tab size: 8 (not used)
11 * indentation:4
12 *
13 * created on: 2010dec24
14 * created by: Markus W. Scherer
15 */
16
17 #ifndef __STRINGTRIEBUILDER_H__
18 #define __STRINGTRIEBUILDER_H__
19
20 #include "unicode/utypes.h"
21 #include "unicode/uobject.h"
22
28 // Forward declaration.
29 struct UHashtable;
30 typedef struct UHashtable UHashtable;
31
36 enum UStringTrieBuildOption {
41 USTRINGTRIE_BUILD_FAST,
52 USTRINGTRIE_BUILD_SMALL
53 };
54
55 U_NAMESPACE_BEGIN
56
63 class U_COMMON_API StringTrieBuilder : public UObject {
64 public:
65 #ifndef U_HIDE_INTERNAL_API
66
67 static UBool hashNode(const void *node);
69 static UBool equalNodes(const void *left, const void *right);
70 #endif /* U_HIDE_INTERNAL_API */
71
72 protected:
73 // Do not enclose the protected default constructor with #ifndef U_HIDE_INTERNAL_API
74 // or else the compiler will create a public default constructor.
76 StringTrieBuilder();
78 virtual ~StringTrieBuilder();
79
80 #ifndef U_HIDE_INTERNAL_API
81
82 void createCompactBuilder(int32_t sizeGuess, UErrorCode &errorCode);
84 void deleteCompactBuilder();
85
87 void build(UStringTrieBuildOption buildOption, int32_t elementsLength, UErrorCode &errorCode);
88
90 int32_t writeNode(int32_t start, int32_t limit, int32_t unitIndex);
92 int32_t writeBranchSubNode(int32_t start, int32_t limit, int32_t unitIndex, int32_t length);
93 #endif /* U_HIDE_INTERNAL_API */
94
95 class Node;
96
97 #ifndef U_HIDE_INTERNAL_API
98
99 Node *makeNode(int32_t start, int32_t limit, int32_t unitIndex, UErrorCode &errorCode);
101 Node *makeBranchSubNode(int32_t start, int32_t limit, int32_t unitIndex,
102 int32_t length, UErrorCode &errorCode);
103 #endif /* U_HIDE_INTERNAL_API */
104
106 virtual int32_t getElementStringLength(int32_t i) const = 0;
108 virtual UChar getElementUnit(int32_t i, int32_t unitIndex) const = 0;
110 virtual int32_t getElementValue(int32_t i) const = 0;
111
112 // Finds the first unit index after this one where
113 // the first and last element have different units again.
115 virtual int32_t getLimitOfLinearMatch(int32_t first, int32_t last, int32_t unitIndex) const = 0;
116
117 // Number of different units at unitIndex.
119 virtual int32_t countElementUnits(int32_t start, int32_t limit, int32_t unitIndex) const = 0;
121 virtual int32_t skipElementsBySomeUnits(int32_t i, int32_t unitIndex, int32_t count) const = 0;
123 virtual int32_t indexOfElementWithNextUnit(int32_t i, int32_t unitIndex, UChar unit) const = 0;
124
126 virtual UBool matchNodesCanHaveValues() const = 0;
127
129 virtual int32_t getMaxBranchLinearSubNodeLength() const = 0;
131 virtual int32_t getMinLinearMatch() const = 0;
133 virtual int32_t getMaxLinearMatchLength() const = 0;
134
135 #ifndef U_HIDE_INTERNAL_API
136 // max(BytesTrie::kMaxBranchLinearSubNodeLength, UCharsTrie::kMaxBranchLinearSubNodeLength).
138 static const int32_t kMaxBranchLinearSubNodeLength=5;
139
140 // Maximum number of nested split-branch levels for a branch on all 2^16 possible UChar units.
141 // log2(2^16/kMaxBranchLinearSubNodeLength) rounded up.
143 static const int32_t kMaxSplitBranchLevels=14;
144
155 Node *registerNode(Node *newNode, UErrorCode &errorCode);
166 Node *registerFinalValue(int32_t value, UErrorCode &errorCode);
167 #endif /* U_HIDE_INTERNAL_API */
168
169 /*
170 * C++ note:
171 * registerNode() and registerFinalValue() take ownership of their input nodes,
172 * and only return owned nodes.
173 * If they see a failure UErrorCode, they will delete the input node.
174 * If they get a NULL pointer, they will record a U_MEMORY_ALLOCATION_ERROR.
175 * If there is a failure, they return NULL.
176 *
177 * NULL Node pointers can be safely passed into other Nodes because
178 * they call the static Node::hashCode() which checks for a NULL pointer first.
179 *
180 * Therefore, as long as builder functions register a new node,
181 * they need to check for failures only before explicitly dereferencing
182 * a Node pointer, or before setting a new UErrorCode.
183 */
184
185 // Hash set of nodes, maps from nodes to integer 1.
187 UHashtable *nodes;
188
189 // Do not conditionalize the following with #ifndef U_HIDE_INTERNAL_API,
190 // it is needed for layout of other objects.
192 class Node : public UObject {
193 public:
194 Node(int32_t initialHash) : hash(initialHash), offset(0) {}
195 inline int32_t hashCode() const { return hash; }
196 // Handles node==NULL.
197 static inline int32_t hashCode(const Node *node) { return node==NULL ? 0 : node->hashCode(); }
198 // Base class operator==() compares the actual class types.
199 virtual UBool operator==(const Node &other) const;
200 inline UBool operator!=(const Node &other) const { return !operator==(other); }
228 virtual int32_t markRightEdgesFirst(int32_t edgeNumber);
229 // write() must set the offset to a positive value.
230 virtual void write(StringTrieBuilder &builder) = 0;
231 // See markRightEdgesFirst.
232 inline void writeUnlessInsideRightEdge(int32_t firstRight, int32_t lastRight,
233 StringTrieBuilder &builder) {
234 // Note: Edge numbers are negative, lastRight<=firstRight.
235 // If offset>0 then this node and its sub-nodes have been written already
236 // and we need not write them again.
237 // If this node is part of the unwritten right branch edge,
238 // then we wait until that is written.
239 if(offset<0 && (offset<lastRight || firstRight<offset)) {
240 write(builder);
241 }
242 }
243 inline int32_t getOffset() const { return offset; }
244 protected:
245 int32_t hash;
246 int32_t offset;
247 };
248
249 #ifndef U_HIDE_INTERNAL_API
250 // This class should not be overridden because
251 // registerFinalValue() compares a stack-allocated FinalValueNode
252 // (stack-allocated so that we don't unnecessarily create lots of duplicate nodes)
253 // with the input node, and the
254 // !Node::operator==(other) used inside FinalValueNode::operator==(other)
255 // will be false if the typeid's are different.
257 class FinalValueNode : public Node {
258 public:
259 FinalValueNode(int32_t v) : Node(0x111111*37+v), value(v) {}
260 virtual UBool operator==(const Node &other) const;
261 virtual void write(StringTrieBuilder &builder);
262 protected:
263 int32_t value;
264 };
265 #endif /* U_HIDE_INTERNAL_API */
266
267 // Do not conditionalize the following with #ifndef U_HIDE_INTERNAL_API,
268 // it is needed for layout of other objects.
272 class ValueNode : public Node {
273 public:
274 ValueNode(int32_t initialHash) : Node(initialHash), hasValue(FALSE), value(0) {}
275 virtual UBool operator==(const Node &other) const;
276 void setValue(int32_t v) {
277 hasValue=TRUE;
278 value=v;
279 hash=hash*37+v;
280 }
281 protected:
282 UBool hasValue;
283 int32_t value;
284 };
285
286 #ifndef U_HIDE_INTERNAL_API
287
290 class IntermediateValueNode : public ValueNode {
291 public:
292 IntermediateValueNode(int32_t v, Node *nextNode)
293 : ValueNode(0x222222*37+hashCode(nextNode)), next(nextNode) { setValue(v); }
294 virtual UBool operator==(const Node &other) const;
295 virtual int32_t markRightEdgesFirst(int32_t edgeNumber);
296 virtual void write(StringTrieBuilder &builder);
297 protected:
298 Node *next;
299 };
300 #endif /* U_HIDE_INTERNAL_API */
301
302 // Do not conditionalize the following with #ifndef U_HIDE_INTERNAL_API,
303 // it is needed for layout of other objects.
307 class LinearMatchNode : public ValueNode {
308 public:
309 LinearMatchNode(int32_t len, Node *nextNode)
310 : ValueNode((0x333333*37+len)*37+hashCode(nextNode)),
311 length(len), next(nextNode) {}
312 virtual UBool operator==(const Node &other) const;
313 virtual int32_t markRightEdgesFirst(int32_t edgeNumber);
314 protected:
315 int32_t length;
316 Node *next;
317 };
318
319 #ifndef U_HIDE_INTERNAL_API
320
323 class BranchNode : public Node {
324 public:
325 BranchNode(int32_t initialHash) : Node(initialHash) {}
326 protected:
327 int32_t firstEdgeNumber;
328 };
329
333 class ListBranchNode : public BranchNode {
334 public:
335 ListBranchNode() : BranchNode(0x444444), length(0) {}
336 virtual UBool operator==(const Node &other) const;
337 virtual int32_t markRightEdgesFirst(int32_t edgeNumber);
338 virtual void write(StringTrieBuilder &builder);
339 // Adds a unit with a final value.
340 void add(int32_t c, int32_t value) {
341 units[length]=(UChar)c;
342 equal[length]=NULL;
343 values[length]=value;
344 ++length;
345 hash=(hash*37+c)*37+value;
346 }
347 // Adds a unit which leads to another match node.
348 void add(int32_t c, Node *node) {
349 units[length]=(UChar)c;
350 equal[length]=node;
351 values[length]=0;
352 ++length;
353 hash=(hash*37+c)*37+hashCode(node);
354 }
355 protected:
356 Node *equal[kMaxBranchLinearSubNodeLength]; // NULL means "has final value".
357 int32_t length;
358 int32_t values[kMaxBranchLinearSubNodeLength];
359 UChar units[kMaxBranchLinearSubNodeLength];
360 };
361
365 class SplitBranchNode : public BranchNode {
366 public:
367 SplitBranchNode(UChar middleUnit, Node *lessThanNode, Node *greaterOrEqualNode)
368 : BranchNode(((0x555555*37+middleUnit)*37+
369 hashCode(lessThanNode))*37+hashCode(greaterOrEqualNode)),
370 unit(middleUnit), lessThan(lessThanNode), greaterOrEqual(greaterOrEqualNode) {}
371 virtual UBool operator==(const Node &other) const;
372 virtual int32_t markRightEdgesFirst(int32_t edgeNumber);
373 virtual void write(StringTrieBuilder &builder);
374 protected:
375 UChar unit;
376 Node *lessThan;
377 Node *greaterOrEqual;
378 };
379
380 // Branch head node, for writing the actual node lead unit.
382 class BranchHeadNode : public ValueNode {
383 public:
384 BranchHeadNode(int32_t len, Node *subNode)
385 : ValueNode((0x666666*37+len)*37+hashCode(subNode)),
386 length(len), next(subNode) {}
387 virtual UBool operator==(const Node &other) const;
388 virtual int32_t markRightEdgesFirst(int32_t edgeNumber);
389 virtual void write(StringTrieBuilder &builder);
390 protected:
391 int32_t length;
392 Node *next; // A branch sub-node.
393 };
394 #endif /* U_HIDE_INTERNAL_API */
395
397 virtual Node *createLinearMatchNode(int32_t i, int32_t unitIndex, int32_t length,
398 Node *nextNode) const = 0;
399
401 virtual int32_t write(int32_t unit) = 0;
403 virtual int32_t writeElementUnits(int32_t i, int32_t unitIndex, int32_t length) = 0;
405 virtual int32_t writeValueAndFinal(int32_t i, UBool isFinal) = 0;
407 virtual int32_t writeValueAndType(UBool hasValue, int32_t value, int32_t node) = 0;
409 virtual int32_t writeDeltaTo(int32_t jumpTarget) = 0;
410 };
411
412 U_NAMESPACE_END
413
414 #endif // __STRINGTRIEBUILDER_H__
icu::StringTrieBuilder::nodes
UHashtable * nodes
Definition: stringtriebuilder.h:187
USTRINGTRIE_BUILD_SMALL
Builds a trie more slowly, attempting to generate a shorter but equivalent serialization.
Definition: stringtriebuilder.h:52
icu::StringTrieBuilder
Base class for string trie builder classes.
Definition: stringtriebuilder.h:63
icu::StringTrieBuilder::Node
Definition: stringtriebuilder.h:192
icu::StringTrieBuilder::FinalValueNode
Definition: stringtriebuilder.h:257
icu::operator==
U_EXPORT UBool operator==(const StringPiece &x, const StringPiece &y)
Global operator == for StringPiece.
icu::StringTrieBuilder::BranchHeadNode
Definition: stringtriebuilder.h:382
U_NAMESPACE_BEGIN
#define U_NAMESPACE_BEGIN
This is used to begin a declaration of a public ICU C++ API.
Definition: uversion.h:131
icu::operator!=
UBool operator!=(const StringPiece &x, const StringPiece &y)
Global operator != for StringPiece.
Definition: stringpiece.h:220
USTRINGTRIE_BUILD_FAST
Builds a trie quickly.
Definition: stringtriebuilder.h:41
NULL
#define NULL
Define NULL if necessary, to 0 for C++ and to ((void *)0) for C.
Definition: utypes.h:188
TRUE
#define TRUE
The TRUE value of a UBool.
Definition: umachine.h:263
icu::StringTrieBuilder::BranchNode
Definition: stringtriebuilder.h:323
icu::StringTrieBuilder::IntermediateValueNode
Definition: stringtriebuilder.h:290
uobject.h
C++ API: Common ICU base class UObject.
UChar
uint16_t UChar
Define UChar to be UCHAR_TYPE, if that is #defined (for example, to char16_t), or wchar_t if that is ...
Definition: umachine.h:337
UStringTrieBuildOption
UStringTrieBuildOption
Build options for BytesTrieBuilder and CharsTrieBuilder.
Definition: stringtriebuilder.h:36
U_NAMESPACE_END
#define U_NAMESPACE_END
This is used to end a declaration of a public ICU C++ API.
Definition: uversion.h:132
icu::StringTrieBuilder::SplitBranchNode
Definition: stringtriebuilder.h:365
icu::StringTrieBuilder::LinearMatchNode
Definition: stringtriebuilder.h:307
UErrorCode
UErrorCode
Error code to replace exception handling, so that the code is compatible with all C++ compilers...
Definition: utypes.h:396
icu::StringTrieBuilder::ValueNode
Definition: stringtriebuilder.h:272
icu::StringTrieBuilder::ListBranchNode
Definition: stringtriebuilder.h:333
utypes.h
Basic definitions for ICU, for both C and C++ APIs.
FALSE
#define FALSE
The FALSE value of a UBool.
Definition: umachine.h:267
U_COMMON_API
#define U_COMMON_API
Set to export library symbols from inside the common library, and to import them from outside...
Definition: utypes.h:359
icu::UObject
UObject is the common ICU "boilerplate" class.
Definition: uobject.h:223
UBool
int8_t UBool
The ICU boolean type.
Definition: umachine.h:259