1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/intl/icu/source/common/ucharstrie.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,411 @@
1.4 +/*
1.5 +*******************************************************************************
1.6 +* Copyright (C) 2010-2011, International Business Machines
1.7 +* Corporation and others. All Rights Reserved.
1.8 +*******************************************************************************
1.9 +* file name: ucharstrie.h
1.10 +* encoding: US-ASCII
1.11 +* tab size: 8 (not used)
1.12 +* indentation:4
1.13 +*
1.14 +* created on: 2010nov14
1.15 +* created by: Markus W. Scherer
1.16 +*/
1.17 +
1.18 +#include "unicode/utypes.h"
1.19 +#include "unicode/appendable.h"
1.20 +#include "unicode/ucharstrie.h"
1.21 +#include "unicode/uobject.h"
1.22 +#include "unicode/utf16.h"
1.23 +#include "cmemory.h"
1.24 +#include "uassert.h"
1.25 +
1.26 +U_NAMESPACE_BEGIN
1.27 +
1.28 +UCharsTrie::~UCharsTrie() {
1.29 + uprv_free(ownedArray_);
1.30 +}
1.31 +
1.32 +UStringTrieResult
1.33 +UCharsTrie::current() const {
1.34 + const UChar *pos=pos_;
1.35 + if(pos==NULL) {
1.36 + return USTRINGTRIE_NO_MATCH;
1.37 + } else {
1.38 + int32_t node;
1.39 + return (remainingMatchLength_<0 && (node=*pos)>=kMinValueLead) ?
1.40 + valueResult(node) : USTRINGTRIE_NO_VALUE;
1.41 + }
1.42 +}
1.43 +
1.44 +UStringTrieResult
1.45 +UCharsTrie::firstForCodePoint(UChar32 cp) {
1.46 + return cp<=0xffff ?
1.47 + first(cp) :
1.48 + (USTRINGTRIE_HAS_NEXT(first(U16_LEAD(cp))) ?
1.49 + next(U16_TRAIL(cp)) :
1.50 + USTRINGTRIE_NO_MATCH);
1.51 +}
1.52 +
1.53 +UStringTrieResult
1.54 +UCharsTrie::nextForCodePoint(UChar32 cp) {
1.55 + return cp<=0xffff ?
1.56 + next(cp) :
1.57 + (USTRINGTRIE_HAS_NEXT(next(U16_LEAD(cp))) ?
1.58 + next(U16_TRAIL(cp)) :
1.59 + USTRINGTRIE_NO_MATCH);
1.60 +}
1.61 +
1.62 +UStringTrieResult
1.63 +UCharsTrie::branchNext(const UChar *pos, int32_t length, int32_t uchar) {
1.64 + // Branch according to the current unit.
1.65 + if(length==0) {
1.66 + length=*pos++;
1.67 + }
1.68 + ++length;
1.69 + // The length of the branch is the number of units to select from.
1.70 + // The data structure encodes a binary search.
1.71 + while(length>kMaxBranchLinearSubNodeLength) {
1.72 + if(uchar<*pos++) {
1.73 + length>>=1;
1.74 + pos=jumpByDelta(pos);
1.75 + } else {
1.76 + length=length-(length>>1);
1.77 + pos=skipDelta(pos);
1.78 + }
1.79 + }
1.80 + // Drop down to linear search for the last few units.
1.81 + // length>=2 because the loop body above sees length>kMaxBranchLinearSubNodeLength>=3
1.82 + // and divides length by 2.
1.83 + do {
1.84 + if(uchar==*pos++) {
1.85 + UStringTrieResult result;
1.86 + int32_t node=*pos;
1.87 + if(node&kValueIsFinal) {
1.88 + // Leave the final value for getValue() to read.
1.89 + result=USTRINGTRIE_FINAL_VALUE;
1.90 + } else {
1.91 + // Use the non-final value as the jump delta.
1.92 + ++pos;
1.93 + // int32_t delta=readValue(pos, node);
1.94 + int32_t delta;
1.95 + if(node<kMinTwoUnitValueLead) {
1.96 + delta=node;
1.97 + } else if(node<kThreeUnitValueLead) {
1.98 + delta=((node-kMinTwoUnitValueLead)<<16)|*pos++;
1.99 + } else {
1.100 + delta=(pos[0]<<16)|pos[1];
1.101 + pos+=2;
1.102 + }
1.103 + // end readValue()
1.104 + pos+=delta;
1.105 + node=*pos;
1.106 + result= node>=kMinValueLead ? valueResult(node) : USTRINGTRIE_NO_VALUE;
1.107 + }
1.108 + pos_=pos;
1.109 + return result;
1.110 + }
1.111 + --length;
1.112 + pos=skipValue(pos);
1.113 + } while(length>1);
1.114 + if(uchar==*pos++) {
1.115 + pos_=pos;
1.116 + int32_t node=*pos;
1.117 + return node>=kMinValueLead ? valueResult(node) : USTRINGTRIE_NO_VALUE;
1.118 + } else {
1.119 + stop();
1.120 + return USTRINGTRIE_NO_MATCH;
1.121 + }
1.122 +}
1.123 +
1.124 +UStringTrieResult
1.125 +UCharsTrie::nextImpl(const UChar *pos, int32_t uchar) {
1.126 + int32_t node=*pos++;
1.127 + for(;;) {
1.128 + if(node<kMinLinearMatch) {
1.129 + return branchNext(pos, node, uchar);
1.130 + } else if(node<kMinValueLead) {
1.131 + // Match the first of length+1 units.
1.132 + int32_t length=node-kMinLinearMatch; // Actual match length minus 1.
1.133 + if(uchar==*pos++) {
1.134 + remainingMatchLength_=--length;
1.135 + pos_=pos;
1.136 + return (length<0 && (node=*pos)>=kMinValueLead) ?
1.137 + valueResult(node) : USTRINGTRIE_NO_VALUE;
1.138 + } else {
1.139 + // No match.
1.140 + break;
1.141 + }
1.142 + } else if(node&kValueIsFinal) {
1.143 + // No further matching units.
1.144 + break;
1.145 + } else {
1.146 + // Skip intermediate value.
1.147 + pos=skipNodeValue(pos, node);
1.148 + node&=kNodeTypeMask;
1.149 + }
1.150 + }
1.151 + stop();
1.152 + return USTRINGTRIE_NO_MATCH;
1.153 +}
1.154 +
1.155 +UStringTrieResult
1.156 +UCharsTrie::next(int32_t uchar) {
1.157 + const UChar *pos=pos_;
1.158 + if(pos==NULL) {
1.159 + return USTRINGTRIE_NO_MATCH;
1.160 + }
1.161 + int32_t length=remainingMatchLength_; // Actual remaining match length minus 1.
1.162 + if(length>=0) {
1.163 + // Remaining part of a linear-match node.
1.164 + if(uchar==*pos++) {
1.165 + remainingMatchLength_=--length;
1.166 + pos_=pos;
1.167 + int32_t node;
1.168 + return (length<0 && (node=*pos)>=kMinValueLead) ?
1.169 + valueResult(node) : USTRINGTRIE_NO_VALUE;
1.170 + } else {
1.171 + stop();
1.172 + return USTRINGTRIE_NO_MATCH;
1.173 + }
1.174 + }
1.175 + return nextImpl(pos, uchar);
1.176 +}
1.177 +
1.178 +UStringTrieResult
1.179 +UCharsTrie::next(const UChar *s, int32_t sLength) {
1.180 + if(sLength<0 ? *s==0 : sLength==0) {
1.181 + // Empty input.
1.182 + return current();
1.183 + }
1.184 + const UChar *pos=pos_;
1.185 + if(pos==NULL) {
1.186 + return USTRINGTRIE_NO_MATCH;
1.187 + }
1.188 + int32_t length=remainingMatchLength_; // Actual remaining match length minus 1.
1.189 + for(;;) {
1.190 + // Fetch the next input unit, if there is one.
1.191 + // Continue a linear-match node without rechecking sLength<0.
1.192 + int32_t uchar;
1.193 + if(sLength<0) {
1.194 + for(;;) {
1.195 + if((uchar=*s++)==0) {
1.196 + remainingMatchLength_=length;
1.197 + pos_=pos;
1.198 + int32_t node;
1.199 + return (length<0 && (node=*pos)>=kMinValueLead) ?
1.200 + valueResult(node) : USTRINGTRIE_NO_VALUE;
1.201 + }
1.202 + if(length<0) {
1.203 + remainingMatchLength_=length;
1.204 + break;
1.205 + }
1.206 + if(uchar!=*pos) {
1.207 + stop();
1.208 + return USTRINGTRIE_NO_MATCH;
1.209 + }
1.210 + ++pos;
1.211 + --length;
1.212 + }
1.213 + } else {
1.214 + for(;;) {
1.215 + if(sLength==0) {
1.216 + remainingMatchLength_=length;
1.217 + pos_=pos;
1.218 + int32_t node;
1.219 + return (length<0 && (node=*pos)>=kMinValueLead) ?
1.220 + valueResult(node) : USTRINGTRIE_NO_VALUE;
1.221 + }
1.222 + uchar=*s++;
1.223 + --sLength;
1.224 + if(length<0) {
1.225 + remainingMatchLength_=length;
1.226 + break;
1.227 + }
1.228 + if(uchar!=*pos) {
1.229 + stop();
1.230 + return USTRINGTRIE_NO_MATCH;
1.231 + }
1.232 + ++pos;
1.233 + --length;
1.234 + }
1.235 + }
1.236 + int32_t node=*pos++;
1.237 + for(;;) {
1.238 + if(node<kMinLinearMatch) {
1.239 + UStringTrieResult result=branchNext(pos, node, uchar);
1.240 + if(result==USTRINGTRIE_NO_MATCH) {
1.241 + return USTRINGTRIE_NO_MATCH;
1.242 + }
1.243 + // Fetch the next input unit, if there is one.
1.244 + if(sLength<0) {
1.245 + if((uchar=*s++)==0) {
1.246 + return result;
1.247 + }
1.248 + } else {
1.249 + if(sLength==0) {
1.250 + return result;
1.251 + }
1.252 + uchar=*s++;
1.253 + --sLength;
1.254 + }
1.255 + if(result==USTRINGTRIE_FINAL_VALUE) {
1.256 + // No further matching units.
1.257 + stop();
1.258 + return USTRINGTRIE_NO_MATCH;
1.259 + }
1.260 + pos=pos_; // branchNext() advanced pos and wrote it to pos_ .
1.261 + node=*pos++;
1.262 + } else if(node<kMinValueLead) {
1.263 + // Match length+1 units.
1.264 + length=node-kMinLinearMatch; // Actual match length minus 1.
1.265 + if(uchar!=*pos) {
1.266 + stop();
1.267 + return USTRINGTRIE_NO_MATCH;
1.268 + }
1.269 + ++pos;
1.270 + --length;
1.271 + break;
1.272 + } else if(node&kValueIsFinal) {
1.273 + // No further matching units.
1.274 + stop();
1.275 + return USTRINGTRIE_NO_MATCH;
1.276 + } else {
1.277 + // Skip intermediate value.
1.278 + pos=skipNodeValue(pos, node);
1.279 + node&=kNodeTypeMask;
1.280 + }
1.281 + }
1.282 + }
1.283 +}
1.284 +
1.285 +const UChar *
1.286 +UCharsTrie::findUniqueValueFromBranch(const UChar *pos, int32_t length,
1.287 + UBool haveUniqueValue, int32_t &uniqueValue) {
1.288 + while(length>kMaxBranchLinearSubNodeLength) {
1.289 + ++pos; // ignore the comparison unit
1.290 + if(NULL==findUniqueValueFromBranch(jumpByDelta(pos), length>>1, haveUniqueValue, uniqueValue)) {
1.291 + return NULL;
1.292 + }
1.293 + length=length-(length>>1);
1.294 + pos=skipDelta(pos);
1.295 + }
1.296 + do {
1.297 + ++pos; // ignore a comparison unit
1.298 + // handle its value
1.299 + int32_t node=*pos++;
1.300 + UBool isFinal=(UBool)(node>>15);
1.301 + node&=0x7fff;
1.302 + int32_t value=readValue(pos, node);
1.303 + pos=skipValue(pos, node);
1.304 + if(isFinal) {
1.305 + if(haveUniqueValue) {
1.306 + if(value!=uniqueValue) {
1.307 + return NULL;
1.308 + }
1.309 + } else {
1.310 + uniqueValue=value;
1.311 + haveUniqueValue=TRUE;
1.312 + }
1.313 + } else {
1.314 + if(!findUniqueValue(pos+value, haveUniqueValue, uniqueValue)) {
1.315 + return NULL;
1.316 + }
1.317 + haveUniqueValue=TRUE;
1.318 + }
1.319 + } while(--length>1);
1.320 + return pos+1; // ignore the last comparison unit
1.321 +}
1.322 +
1.323 +UBool
1.324 +UCharsTrie::findUniqueValue(const UChar *pos, UBool haveUniqueValue, int32_t &uniqueValue) {
1.325 + int32_t node=*pos++;
1.326 + for(;;) {
1.327 + if(node<kMinLinearMatch) {
1.328 + if(node==0) {
1.329 + node=*pos++;
1.330 + }
1.331 + pos=findUniqueValueFromBranch(pos, node+1, haveUniqueValue, uniqueValue);
1.332 + if(pos==NULL) {
1.333 + return FALSE;
1.334 + }
1.335 + haveUniqueValue=TRUE;
1.336 + node=*pos++;
1.337 + } else if(node<kMinValueLead) {
1.338 + // linear-match node
1.339 + pos+=node-kMinLinearMatch+1; // Ignore the match units.
1.340 + node=*pos++;
1.341 + } else {
1.342 + UBool isFinal=(UBool)(node>>15);
1.343 + int32_t value;
1.344 + if(isFinal) {
1.345 + value=readValue(pos, node&0x7fff);
1.346 + } else {
1.347 + value=readNodeValue(pos, node);
1.348 + }
1.349 + if(haveUniqueValue) {
1.350 + if(value!=uniqueValue) {
1.351 + return FALSE;
1.352 + }
1.353 + } else {
1.354 + uniqueValue=value;
1.355 + haveUniqueValue=TRUE;
1.356 + }
1.357 + if(isFinal) {
1.358 + return TRUE;
1.359 + }
1.360 + pos=skipNodeValue(pos, node);
1.361 + node&=kNodeTypeMask;
1.362 + }
1.363 + }
1.364 +}
1.365 +
1.366 +int32_t
1.367 +UCharsTrie::getNextUChars(Appendable &out) const {
1.368 + const UChar *pos=pos_;
1.369 + if(pos==NULL) {
1.370 + return 0;
1.371 + }
1.372 + if(remainingMatchLength_>=0) {
1.373 + out.appendCodeUnit(*pos); // Next unit of a pending linear-match node.
1.374 + return 1;
1.375 + }
1.376 + int32_t node=*pos++;
1.377 + if(node>=kMinValueLead) {
1.378 + if(node&kValueIsFinal) {
1.379 + return 0;
1.380 + } else {
1.381 + pos=skipNodeValue(pos, node);
1.382 + node&=kNodeTypeMask;
1.383 + }
1.384 + }
1.385 + if(node<kMinLinearMatch) {
1.386 + if(node==0) {
1.387 + node=*pos++;
1.388 + }
1.389 + out.reserveAppendCapacity(++node);
1.390 + getNextBranchUChars(pos, node, out);
1.391 + return node;
1.392 + } else {
1.393 + // First unit of the linear-match node.
1.394 + out.appendCodeUnit(*pos);
1.395 + return 1;
1.396 + }
1.397 +}
1.398 +
1.399 +void
1.400 +UCharsTrie::getNextBranchUChars(const UChar *pos, int32_t length, Appendable &out) {
1.401 + while(length>kMaxBranchLinearSubNodeLength) {
1.402 + ++pos; // ignore the comparison unit
1.403 + getNextBranchUChars(jumpByDelta(pos), length>>1, out);
1.404 + length=length-(length>>1);
1.405 + pos=skipDelta(pos);
1.406 + }
1.407 + do {
1.408 + out.appendCodeUnit(*pos++);
1.409 + pos=skipValue(pos);
1.410 + } while(--length>1);
1.411 + out.appendCodeUnit(*pos);
1.412 +}
1.413 +
1.414 +U_NAMESPACE_END
