// © 2016 and later: Unicode, Inc. and others. // License & terms of use: http://www.unicode.org/copyright.html /* ******************************************************************************* * Copyright (C) 2010-2011, International Business Machines * Corporation and others. All Rights Reserved. ******************************************************************************* * file name: ucharstrie.h * encoding: UTF-8 * 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 char16_t *pos=pos_; if(pos==nullptr) { 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 char16_t *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 char16_t *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 char16_t *pos=pos_; if(pos==nullptr) { 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(ConstChar16Ptr ptr, int32_t sLength) { const char16_t *s=ptr; if(sLength<0 ? *s==0 : sLength==0) { // Empty input. return current(); } const char16_t *pos=pos_; if(pos==nullptr) { 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 char16_t * UCharsTrie::findUniqueValueFromBranch(const char16_t *pos, int32_t length, UBool haveUniqueValue, int32_t &uniqueValue) { while(length>kMaxBranchLinearSubNodeLength) { ++pos; // ignore the comparison unit if(nullptr==findUniqueValueFromBranch(jumpByDelta(pos), length>>1, haveUniqueValue, uniqueValue)) { return nullptr; } 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 nullptr; } } else { uniqueValue=value; haveUniqueValue=true; } } else { if(!findUniqueValue(pos+value, haveUniqueValue, uniqueValue)) { return nullptr; } haveUniqueValue=true; } } while(--length>1); return pos+1; // ignore the last comparison unit } UBool UCharsTrie::findUniqueValue(const char16_t *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==nullptr) { 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 char16_t *pos=pos_; if(pos==nullptr) { 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 char16_t *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