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-rw-r--r--intl/icu/source/common/ucharstrie.cpp411
1 files changed, 411 insertions, 0 deletions
diff --git a/intl/icu/source/common/ucharstrie.cpp b/intl/icu/source/common/ucharstrie.cpp
new file mode 100644
index 0000000..476271d
--- /dev/null
+++ b/intl/icu/source/common/ucharstrie.cpp
@@ -0,0 +1,411 @@
+/*
+*******************************************************************************
+* Copyright (C) 2010-2011, International Business Machines
+* Corporation and others. All Rights Reserved.
+*******************************************************************************
+* file name: ucharstrie.h
+* encoding: US-ASCII
+* tab size: 8 (not used)
+* indentation:4
+*
+* created on: 2010nov14
+* created by: Markus W. Scherer
+*/
+
+#include "unicode/utypes.h"
+#include "unicode/appendable.h"
+#include "unicode/ucharstrie.h"
+#include "unicode/uobject.h"
+#include "unicode/utf16.h"
+#include "cmemory.h"
+#include "uassert.h"
+
+U_NAMESPACE_BEGIN
+
+UCharsTrie::~UCharsTrie() {
+ uprv_free(ownedArray_);
+}
+
+UStringTrieResult
+UCharsTrie::current() const {
+ const UChar *pos=pos_;
+ if(pos==NULL) {
+ return USTRINGTRIE_NO_MATCH;
+ } else {
+ int32_t node;
+ return (remainingMatchLength_<0 && (node=*pos)>=kMinValueLead) ?
+ valueResult(node) : USTRINGTRIE_NO_VALUE;
+ }
+}
+
+UStringTrieResult
+UCharsTrie::firstForCodePoint(UChar32 cp) {
+ return cp<=0xffff ?
+ first(cp) :
+ (USTRINGTRIE_HAS_NEXT(first(U16_LEAD(cp))) ?
+ next(U16_TRAIL(cp)) :
+ USTRINGTRIE_NO_MATCH);
+}
+
+UStringTrieResult
+UCharsTrie::nextForCodePoint(UChar32 cp) {
+ return cp<=0xffff ?
+ next(cp) :
+ (USTRINGTRIE_HAS_NEXT(next(U16_LEAD(cp))) ?
+ next(U16_TRAIL(cp)) :
+ USTRINGTRIE_NO_MATCH);
+}
+
+UStringTrieResult
+UCharsTrie::branchNext(const UChar *pos, int32_t length, int32_t uchar) {
+ // Branch according to the current unit.
+ if(length==0) {
+ length=*pos++;
+ }
+ ++length;
+ // The length of the branch is the number of units to select from.
+ // The data structure encodes a binary search.
+ while(length>kMaxBranchLinearSubNodeLength) {
+ if(uchar<*pos++) {
+ length>>=1;
+ pos=jumpByDelta(pos);
+ } else {
+ length=length-(length>>1);
+ pos=skipDelta(pos);
+ }
+ }
+ // Drop down to linear search for the last few units.
+ // length>=2 because the loop body above sees length>kMaxBranchLinearSubNodeLength>=3
+ // and divides length by 2.
+ do {
+ if(uchar==*pos++) {
+ UStringTrieResult result;
+ int32_t node=*pos;
+ if(node&kValueIsFinal) {
+ // Leave the final value for getValue() to read.
+ result=USTRINGTRIE_FINAL_VALUE;
+ } else {
+ // Use the non-final value as the jump delta.
+ ++pos;
+ // int32_t delta=readValue(pos, node);
+ int32_t delta;
+ if(node<kMinTwoUnitValueLead) {
+ delta=node;
+ } else if(node<kThreeUnitValueLead) {
+ delta=((node-kMinTwoUnitValueLead)<<16)|*pos++;
+ } else {
+ delta=(pos[0]<<16)|pos[1];
+ pos+=2;
+ }
+ // end readValue()
+ pos+=delta;
+ node=*pos;
+ result= node>=kMinValueLead ? valueResult(node) : USTRINGTRIE_NO_VALUE;
+ }
+ pos_=pos;
+ return result;
+ }
+ --length;
+ pos=skipValue(pos);
+ } while(length>1);
+ if(uchar==*pos++) {
+ pos_=pos;
+ int32_t node=*pos;
+ return node>=kMinValueLead ? valueResult(node) : USTRINGTRIE_NO_VALUE;
+ } else {
+ stop();
+ return USTRINGTRIE_NO_MATCH;
+ }
+}
+
+UStringTrieResult
+UCharsTrie::nextImpl(const UChar *pos, int32_t uchar) {
+ int32_t node=*pos++;
+ for(;;) {
+ if(node<kMinLinearMatch) {
+ return branchNext(pos, node, uchar);
+ } else if(node<kMinValueLead) {
+ // Match the first of length+1 units.
+ int32_t length=node-kMinLinearMatch; // Actual match length minus 1.
+ if(uchar==*pos++) {
+ remainingMatchLength_=--length;
+ pos_=pos;
+ return (length<0 && (node=*pos)>=kMinValueLead) ?
+ valueResult(node) : USTRINGTRIE_NO_VALUE;
+ } else {
+ // No match.
+ break;
+ }
+ } else if(node&kValueIsFinal) {
+ // No further matching units.
+ break;
+ } else {
+ // Skip intermediate value.
+ pos=skipNodeValue(pos, node);
+ node&=kNodeTypeMask;
+ }
+ }
+ stop();
+ return USTRINGTRIE_NO_MATCH;
+}
+
+UStringTrieResult
+UCharsTrie::next(int32_t uchar) {
+ const UChar *pos=pos_;
+ if(pos==NULL) {
+ return USTRINGTRIE_NO_MATCH;
+ }
+ int32_t length=remainingMatchLength_; // Actual remaining match length minus 1.
+ if(length>=0) {
+ // Remaining part of a linear-match node.
+ if(uchar==*pos++) {
+ remainingMatchLength_=--length;
+ pos_=pos;
+ int32_t node;
+ return (length<0 && (node=*pos)>=kMinValueLead) ?
+ valueResult(node) : USTRINGTRIE_NO_VALUE;
+ } else {
+ stop();
+ return USTRINGTRIE_NO_MATCH;
+ }
+ }
+ return nextImpl(pos, uchar);
+}
+
+UStringTrieResult
+UCharsTrie::next(const UChar *s, int32_t sLength) {
+ if(sLength<0 ? *s==0 : sLength==0) {
+ // Empty input.
+ return current();
+ }
+ const UChar *pos=pos_;
+ if(pos==NULL) {
+ return USTRINGTRIE_NO_MATCH;
+ }
+ int32_t length=remainingMatchLength_; // Actual remaining match length minus 1.
+ for(;;) {
+ // Fetch the next input unit, if there is one.
+ // Continue a linear-match node without rechecking sLength<0.
+ int32_t uchar;
+ if(sLength<0) {
+ for(;;) {
+ if((uchar=*s++)==0) {
+ remainingMatchLength_=length;
+ pos_=pos;
+ int32_t node;
+ return (length<0 && (node=*pos)>=kMinValueLead) ?
+ valueResult(node) : USTRINGTRIE_NO_VALUE;
+ }
+ if(length<0) {
+ remainingMatchLength_=length;
+ break;
+ }
+ if(uchar!=*pos) {
+ stop();
+ return USTRINGTRIE_NO_MATCH;
+ }
+ ++pos;
+ --length;
+ }
+ } else {
+ for(;;) {
+ if(sLength==0) {
+ remainingMatchLength_=length;
+ pos_=pos;
+ int32_t node;
+ return (length<0 && (node=*pos)>=kMinValueLead) ?
+ valueResult(node) : USTRINGTRIE_NO_VALUE;
+ }
+ uchar=*s++;
+ --sLength;
+ if(length<0) {
+ remainingMatchLength_=length;
+ break;
+ }
+ if(uchar!=*pos) {
+ stop();
+ return USTRINGTRIE_NO_MATCH;
+ }
+ ++pos;
+ --length;
+ }
+ }
+ int32_t node=*pos++;
+ for(;;) {
+ if(node<kMinLinearMatch) {
+ UStringTrieResult result=branchNext(pos, node, uchar);
+ if(result==USTRINGTRIE_NO_MATCH) {
+ return USTRINGTRIE_NO_MATCH;
+ }
+ // Fetch the next input unit, if there is one.
+ if(sLength<0) {
+ if((uchar=*s++)==0) {
+ return result;
+ }
+ } else {
+ if(sLength==0) {
+ return result;
+ }
+ uchar=*s++;
+ --sLength;
+ }
+ if(result==USTRINGTRIE_FINAL_VALUE) {
+ // No further matching units.
+ stop();
+ return USTRINGTRIE_NO_MATCH;
+ }
+ pos=pos_; // branchNext() advanced pos and wrote it to pos_ .
+ node=*pos++;
+ } else if(node<kMinValueLead) {
+ // Match length+1 units.
+ length=node-kMinLinearMatch; // Actual match length minus 1.
+ if(uchar!=*pos) {
+ stop();
+ return USTRINGTRIE_NO_MATCH;
+ }
+ ++pos;
+ --length;
+ break;
+ } else if(node&kValueIsFinal) {
+ // No further matching units.
+ stop();
+ return USTRINGTRIE_NO_MATCH;
+ } else {
+ // Skip intermediate value.
+ pos=skipNodeValue(pos, node);
+ node&=kNodeTypeMask;
+ }
+ }
+ }
+}
+
+const UChar *
+UCharsTrie::findUniqueValueFromBranch(const UChar *pos, int32_t length,
+ UBool haveUniqueValue, int32_t &uniqueValue) {
+ while(length>kMaxBranchLinearSubNodeLength) {
+ ++pos; // ignore the comparison unit
+ if(NULL==findUniqueValueFromBranch(jumpByDelta(pos), length>>1, haveUniqueValue, uniqueValue)) {
+ return NULL;
+ }
+ length=length-(length>>1);
+ pos=skipDelta(pos);
+ }
+ do {
+ ++pos; // ignore a comparison unit
+ // handle its value
+ int32_t node=*pos++;
+ UBool isFinal=(UBool)(node>>15);
+ node&=0x7fff;
+ int32_t value=readValue(pos, node);
+ pos=skipValue(pos, node);
+ if(isFinal) {
+ if(haveUniqueValue) {
+ if(value!=uniqueValue) {
+ return NULL;
+ }
+ } else {
+ uniqueValue=value;
+ haveUniqueValue=TRUE;
+ }
+ } else {
+ if(!findUniqueValue(pos+value, haveUniqueValue, uniqueValue)) {
+ return NULL;
+ }
+ haveUniqueValue=TRUE;
+ }
+ } while(--length>1);
+ return pos+1; // ignore the last comparison unit
+}
+
+UBool
+UCharsTrie::findUniqueValue(const UChar *pos, UBool haveUniqueValue, int32_t &uniqueValue) {
+ int32_t node=*pos++;
+ for(;;) {
+ if(node<kMinLinearMatch) {
+ if(node==0) {
+ node=*pos++;
+ }
+ pos=findUniqueValueFromBranch(pos, node+1, haveUniqueValue, uniqueValue);
+ if(pos==NULL) {
+ return FALSE;
+ }
+ haveUniqueValue=TRUE;
+ node=*pos++;
+ } else if(node<kMinValueLead) {
+ // linear-match node
+ pos+=node-kMinLinearMatch+1; // Ignore the match units.
+ node=*pos++;
+ } else {
+ UBool isFinal=(UBool)(node>>15);
+ int32_t value;
+ if(isFinal) {
+ value=readValue(pos, node&0x7fff);
+ } else {
+ value=readNodeValue(pos, node);
+ }
+ if(haveUniqueValue) {
+ if(value!=uniqueValue) {
+ return FALSE;
+ }
+ } else {
+ uniqueValue=value;
+ haveUniqueValue=TRUE;
+ }
+ if(isFinal) {
+ return TRUE;
+ }
+ pos=skipNodeValue(pos, node);
+ node&=kNodeTypeMask;
+ }
+ }
+}
+
+int32_t
+UCharsTrie::getNextUChars(Appendable &out) const {
+ const UChar *pos=pos_;
+ if(pos==NULL) {
+ return 0;
+ }
+ if(remainingMatchLength_>=0) {
+ out.appendCodeUnit(*pos); // Next unit of a pending linear-match node.
+ return 1;
+ }
+ int32_t node=*pos++;
+ if(node>=kMinValueLead) {
+ if(node&kValueIsFinal) {
+ return 0;
+ } else {
+ pos=skipNodeValue(pos, node);
+ node&=kNodeTypeMask;
+ }
+ }
+ if(node<kMinLinearMatch) {
+ if(node==0) {
+ node=*pos++;
+ }
+ out.reserveAppendCapacity(++node);
+ getNextBranchUChars(pos, node, out);
+ return node;
+ } else {
+ // First unit of the linear-match node.
+ out.appendCodeUnit(*pos);
+ return 1;
+ }
+}
+
+void
+UCharsTrie::getNextBranchUChars(const UChar *pos, int32_t length, Appendable &out) {
+ while(length>kMaxBranchLinearSubNodeLength) {
+ ++pos; // ignore the comparison unit
+ getNextBranchUChars(jumpByDelta(pos), length>>1, out);
+ length=length-(length>>1);
+ pos=skipDelta(pos);
+ }
+ do {
+ out.appendCodeUnit(*pos++);
+ pos=skipValue(pos);
+ } while(--length>1);
+ out.appendCodeUnit(*pos);
+}
+
+U_NAMESPACE_END