scuffed-code/icu4c/source/common/ucharstriebuilder.cpp
2017-08-04 17:44:00 +00:00

444 lines
13 KiB
C++

// © 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/*
*******************************************************************************
* Copyright (C) 2010-2012, International Business Machines
* Corporation and others. All Rights Reserved.
*******************************************************************************
* file name: ucharstriebuilder.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/ucharstrie.h"
#include "unicode/ucharstriebuilder.h"
#include "unicode/unistr.h"
#include "unicode/ustring.h"
#include "cmemory.h"
#include "uarrsort.h"
#include "uassert.h"
#include "uhash.h"
#include "ustr_imp.h"
U_NAMESPACE_BEGIN
/*
* Note: This builder implementation stores (string, value) pairs with full copies
* of the 16-bit-unit sequences, until the UCharsTrie is built.
* It might(!) take less memory if we collected the data in a temporary, dynamic trie.
*/
class UCharsTrieElement : public UMemory {
public:
// Use compiler's default constructor, initializes nothing.
void setTo(const UnicodeString &s, int32_t val, UnicodeString &strings, UErrorCode &errorCode);
UnicodeString getString(const UnicodeString &strings) const {
int32_t length=strings[stringOffset];
return strings.tempSubString(stringOffset+1, length);
}
int32_t getStringLength(const UnicodeString &strings) const {
return strings[stringOffset];
}
UChar charAt(int32_t index, const UnicodeString &strings) const {
return strings[stringOffset+1+index];
}
int32_t getValue() const { return value; }
int32_t compareStringTo(const UCharsTrieElement &o, const UnicodeString &strings) const;
private:
// The first strings unit contains the string length.
// (Compared with a stringLength field here, this saves 2 bytes per string.)
int32_t stringOffset;
int32_t value;
};
void
UCharsTrieElement::setTo(const UnicodeString &s, int32_t val,
UnicodeString &strings, UErrorCode &errorCode) {
if(U_FAILURE(errorCode)) {
return;
}
int32_t length=s.length();
if(length>0xffff) {
// Too long: We store the length in 1 unit.
errorCode=U_INDEX_OUTOFBOUNDS_ERROR;
return;
}
stringOffset=strings.length();
strings.append((UChar)length);
value=val;
strings.append(s);
}
int32_t
UCharsTrieElement::compareStringTo(const UCharsTrieElement &other, const UnicodeString &strings) const {
return getString(strings).compare(other.getString(strings));
}
UCharsTrieBuilder::UCharsTrieBuilder(UErrorCode & /*errorCode*/)
: elements(NULL), elementsCapacity(0), elementsLength(0),
uchars(NULL), ucharsCapacity(0), ucharsLength(0) {}
UCharsTrieBuilder::~UCharsTrieBuilder() {
delete[] elements;
uprv_free(uchars);
}
UCharsTrieBuilder &
UCharsTrieBuilder::add(const UnicodeString &s, int32_t value, UErrorCode &errorCode) {
if(U_FAILURE(errorCode)) {
return *this;
}
if(ucharsLength>0) {
// Cannot add elements after building.
errorCode=U_NO_WRITE_PERMISSION;
return *this;
}
if(elementsLength==elementsCapacity) {
int32_t newCapacity;
if(elementsCapacity==0) {
newCapacity=1024;
} else {
newCapacity=4*elementsCapacity;
}
UCharsTrieElement *newElements=new UCharsTrieElement[newCapacity];
if(newElements==NULL) {
errorCode=U_MEMORY_ALLOCATION_ERROR;
return *this;
}
if(elementsLength>0) {
uprv_memcpy(newElements, elements, (size_t)elementsLength*sizeof(UCharsTrieElement));
}
delete[] elements;
elements=newElements;
elementsCapacity=newCapacity;
}
elements[elementsLength++].setTo(s, value, strings, errorCode);
if(U_SUCCESS(errorCode) && strings.isBogus()) {
errorCode=U_MEMORY_ALLOCATION_ERROR;
}
return *this;
}
U_CDECL_BEGIN
static int32_t U_CALLCONV
compareElementStrings(const void *context, const void *left, const void *right) {
const UnicodeString *strings=static_cast<const UnicodeString *>(context);
const UCharsTrieElement *leftElement=static_cast<const UCharsTrieElement *>(left);
const UCharsTrieElement *rightElement=static_cast<const UCharsTrieElement *>(right);
return leftElement->compareStringTo(*rightElement, *strings);
}
U_CDECL_END
UCharsTrie *
UCharsTrieBuilder::build(UStringTrieBuildOption buildOption, UErrorCode &errorCode) {
buildUChars(buildOption, errorCode);
UCharsTrie *newTrie=NULL;
if(U_SUCCESS(errorCode)) {
newTrie=new UCharsTrie(uchars, uchars+(ucharsCapacity-ucharsLength));
if(newTrie==NULL) {
errorCode=U_MEMORY_ALLOCATION_ERROR;
} else {
uchars=NULL; // The new trie now owns the array.
ucharsCapacity=0;
}
}
return newTrie;
}
UnicodeString &
UCharsTrieBuilder::buildUnicodeString(UStringTrieBuildOption buildOption, UnicodeString &result,
UErrorCode &errorCode) {
buildUChars(buildOption, errorCode);
if(U_SUCCESS(errorCode)) {
result.setTo(FALSE, uchars+(ucharsCapacity-ucharsLength), ucharsLength);
}
return result;
}
void
UCharsTrieBuilder::buildUChars(UStringTrieBuildOption buildOption, UErrorCode &errorCode) {
if(U_FAILURE(errorCode)) {
return;
}
if(uchars!=NULL && ucharsLength>0) {
// Already built.
return;
}
if(ucharsLength==0) {
if(elementsLength==0) {
errorCode=U_INDEX_OUTOFBOUNDS_ERROR;
return;
}
if(strings.isBogus()) {
errorCode=U_MEMORY_ALLOCATION_ERROR;
return;
}
uprv_sortArray(elements, elementsLength, (int32_t)sizeof(UCharsTrieElement),
compareElementStrings, &strings,
FALSE, // need not be a stable sort
&errorCode);
if(U_FAILURE(errorCode)) {
return;
}
// Duplicate strings are not allowed.
UnicodeString prev=elements[0].getString(strings);
for(int32_t i=1; i<elementsLength; ++i) {
UnicodeString current=elements[i].getString(strings);
if(prev==current) {
errorCode=U_ILLEGAL_ARGUMENT_ERROR;
return;
}
prev.fastCopyFrom(current);
}
}
// Create and UChar-serialize the trie for the elements.
ucharsLength=0;
int32_t capacity=strings.length();
if(capacity<1024) {
capacity=1024;
}
if(ucharsCapacity<capacity) {
uprv_free(uchars);
uchars=static_cast<UChar *>(uprv_malloc(capacity*2));
if(uchars==NULL) {
errorCode=U_MEMORY_ALLOCATION_ERROR;
ucharsCapacity=0;
return;
}
ucharsCapacity=capacity;
}
StringTrieBuilder::build(buildOption, elementsLength, errorCode);
if(uchars==NULL) {
errorCode=U_MEMORY_ALLOCATION_ERROR;
}
}
int32_t
UCharsTrieBuilder::getElementStringLength(int32_t i) const {
return elements[i].getStringLength(strings);
}
UChar
UCharsTrieBuilder::getElementUnit(int32_t i, int32_t unitIndex) const {
return elements[i].charAt(unitIndex, strings);
}
int32_t
UCharsTrieBuilder::getElementValue(int32_t i) const {
return elements[i].getValue();
}
int32_t
UCharsTrieBuilder::getLimitOfLinearMatch(int32_t first, int32_t last, int32_t unitIndex) const {
const UCharsTrieElement &firstElement=elements[first];
const UCharsTrieElement &lastElement=elements[last];
int32_t minStringLength=firstElement.getStringLength(strings);
while(++unitIndex<minStringLength &&
firstElement.charAt(unitIndex, strings)==
lastElement.charAt(unitIndex, strings)) {}
return unitIndex;
}
int32_t
UCharsTrieBuilder::countElementUnits(int32_t start, int32_t limit, int32_t unitIndex) const {
int32_t length=0; // Number of different units at unitIndex.
int32_t i=start;
do {
UChar unit=elements[i++].charAt(unitIndex, strings);
while(i<limit && unit==elements[i].charAt(unitIndex, strings)) {
++i;
}
++length;
} while(i<limit);
return length;
}
int32_t
UCharsTrieBuilder::skipElementsBySomeUnits(int32_t i, int32_t unitIndex, int32_t count) const {
do {
UChar unit=elements[i++].charAt(unitIndex, strings);
while(unit==elements[i].charAt(unitIndex, strings)) {
++i;
}
} while(--count>0);
return i;
}
int32_t
UCharsTrieBuilder::indexOfElementWithNextUnit(int32_t i, int32_t unitIndex, UChar unit) const {
while(unit==elements[i].charAt(unitIndex, strings)) {
++i;
}
return i;
}
UCharsTrieBuilder::UCTLinearMatchNode::UCTLinearMatchNode(const UChar *units, int32_t len, Node *nextNode)
: LinearMatchNode(len, nextNode), s(units) {
hash=hash*37u+ustr_hashUCharsN(units, len);
}
UBool
UCharsTrieBuilder::UCTLinearMatchNode::operator==(const Node &other) const {
if(this==&other) {
return TRUE;
}
if(!LinearMatchNode::operator==(other)) {
return FALSE;
}
const UCTLinearMatchNode &o=(const UCTLinearMatchNode &)other;
return 0==u_memcmp(s, o.s, length);
}
void
UCharsTrieBuilder::UCTLinearMatchNode::write(StringTrieBuilder &builder) {
UCharsTrieBuilder &b=(UCharsTrieBuilder &)builder;
next->write(builder);
b.write(s, length);
offset=b.writeValueAndType(hasValue, value, b.getMinLinearMatch()+length-1);
}
StringTrieBuilder::Node *
UCharsTrieBuilder::createLinearMatchNode(int32_t i, int32_t unitIndex, int32_t length,
Node *nextNode) const {
return new UCTLinearMatchNode(
elements[i].getString(strings).getBuffer()+unitIndex,
length,
nextNode);
}
UBool
UCharsTrieBuilder::ensureCapacity(int32_t length) {
if(uchars==NULL) {
return FALSE; // previous memory allocation had failed
}
if(length>ucharsCapacity) {
int32_t newCapacity=ucharsCapacity;
do {
newCapacity*=2;
} while(newCapacity<=length);
UChar *newUChars=static_cast<UChar *>(uprv_malloc(newCapacity*2));
if(newUChars==NULL) {
// unable to allocate memory
uprv_free(uchars);
uchars=NULL;
ucharsCapacity=0;
return FALSE;
}
u_memcpy(newUChars+(newCapacity-ucharsLength),
uchars+(ucharsCapacity-ucharsLength), ucharsLength);
uprv_free(uchars);
uchars=newUChars;
ucharsCapacity=newCapacity;
}
return TRUE;
}
int32_t
UCharsTrieBuilder::write(int32_t unit) {
int32_t newLength=ucharsLength+1;
if(ensureCapacity(newLength)) {
ucharsLength=newLength;
uchars[ucharsCapacity-ucharsLength]=(UChar)unit;
}
return ucharsLength;
}
int32_t
UCharsTrieBuilder::write(const UChar *s, int32_t length) {
int32_t newLength=ucharsLength+length;
if(ensureCapacity(newLength)) {
ucharsLength=newLength;
u_memcpy(uchars+(ucharsCapacity-ucharsLength), s, length);
}
return ucharsLength;
}
int32_t
UCharsTrieBuilder::writeElementUnits(int32_t i, int32_t unitIndex, int32_t length) {
return write(elements[i].getString(strings).getBuffer()+unitIndex, length);
}
int32_t
UCharsTrieBuilder::writeValueAndFinal(int32_t i, UBool isFinal) {
if(0<=i && i<=UCharsTrie::kMaxOneUnitValue) {
return write(i|(isFinal<<15));
}
UChar intUnits[3];
int32_t length;
if(i<0 || i>UCharsTrie::kMaxTwoUnitValue) {
intUnits[0]=(UChar)(UCharsTrie::kThreeUnitValueLead);
intUnits[1]=(UChar)((uint32_t)i>>16);
intUnits[2]=(UChar)i;
length=3;
// } else if(i<=UCharsTrie::kMaxOneUnitValue) {
// intUnits[0]=(UChar)(i);
// length=1;
} else {
intUnits[0]=(UChar)(UCharsTrie::kMinTwoUnitValueLead+(i>>16));
intUnits[1]=(UChar)i;
length=2;
}
intUnits[0]=(UChar)(intUnits[0]|(isFinal<<15));
return write(intUnits, length);
}
int32_t
UCharsTrieBuilder::writeValueAndType(UBool hasValue, int32_t value, int32_t node) {
if(!hasValue) {
return write(node);
}
UChar intUnits[3];
int32_t length;
if(value<0 || value>UCharsTrie::kMaxTwoUnitNodeValue) {
intUnits[0]=(UChar)(UCharsTrie::kThreeUnitNodeValueLead);
intUnits[1]=(UChar)((uint32_t)value>>16);
intUnits[2]=(UChar)value;
length=3;
} else if(value<=UCharsTrie::kMaxOneUnitNodeValue) {
intUnits[0]=(UChar)((value+1)<<6);
length=1;
} else {
intUnits[0]=(UChar)(UCharsTrie::kMinTwoUnitNodeValueLead+((value>>10)&0x7fc0));
intUnits[1]=(UChar)value;
length=2;
}
intUnits[0]|=(UChar)node;
return write(intUnits, length);
}
int32_t
UCharsTrieBuilder::writeDeltaTo(int32_t jumpTarget) {
int32_t i=ucharsLength-jumpTarget;
U_ASSERT(i>=0);
if(i<=UCharsTrie::kMaxOneUnitDelta) {
return write(i);
}
UChar intUnits[3];
int32_t length;
if(i<=UCharsTrie::kMaxTwoUnitDelta) {
intUnits[0]=(UChar)(UCharsTrie::kMinTwoUnitDeltaLead+(i>>16));
length=1;
} else {
intUnits[0]=(UChar)(UCharsTrie::kThreeUnitDeltaLead);
intUnits[1]=(UChar)(i>>16);
length=2;
}
intUnits[length++]=(UChar)i;
return write(intUnits, length);
}
U_NAMESPACE_END