godot/thirdparty/icu4c/common/unistr_cnv.cpp
2024-10-24 22:47:59 +03:00

418 lines
12 KiB
C++

// © 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/*
*******************************************************************************
*
* Copyright (C) 1999-2014, International Business Machines
* Corporation and others. All Rights Reserved.
*
*******************************************************************************
* file name: unistr_cnv.cpp
* encoding: UTF-8
* tab size: 8 (not used)
* indentation:2
*
* created on: 2004aug19
* created by: Markus W. Scherer
*
* Character conversion functions moved here from unistr.cpp
*/
#include "unicode/utypes.h"
#if !UCONFIG_NO_CONVERSION
#include "unicode/putil.h"
#include "cstring.h"
#include "cmemory.h"
#include "unicode/ustring.h"
#include "unicode/unistr.h"
#include "unicode/ucnv.h"
#include "ucnv_imp.h"
#include "putilimp.h"
#include "ustr_cnv.h"
#include "ustr_imp.h"
U_NAMESPACE_BEGIN
//========================================
// Constructors
//========================================
#if !U_CHARSET_IS_UTF8
UnicodeString::UnicodeString(const char *codepageData) {
fUnion.fFields.fLengthAndFlags = kShortString;
if(codepageData != 0) {
doCodepageCreate(codepageData, (int32_t)uprv_strlen(codepageData), 0);
}
}
UnicodeString::UnicodeString(const char *codepageData,
int32_t dataLength) {
fUnion.fFields.fLengthAndFlags = kShortString;
if(codepageData != 0) {
doCodepageCreate(codepageData, dataLength, 0);
}
}
// else see unistr.cpp
#endif
UnicodeString::UnicodeString(const char *codepageData,
const char *codepage) {
fUnion.fFields.fLengthAndFlags = kShortString;
if (codepageData != nullptr) {
doCodepageCreate(codepageData, static_cast<int32_t>(uprv_strlen(codepageData)), codepage);
}
}
UnicodeString::UnicodeString(const char *codepageData,
int32_t dataLength,
const char *codepage) {
fUnion.fFields.fLengthAndFlags = kShortString;
if (codepageData != nullptr) {
doCodepageCreate(codepageData, dataLength, codepage);
}
}
UnicodeString::UnicodeString(const char *src, int32_t srcLength,
UConverter *cnv,
UErrorCode &errorCode) {
fUnion.fFields.fLengthAndFlags = kShortString;
if(U_SUCCESS(errorCode)) {
// check arguments
if(src==nullptr) {
// treat as an empty string, do nothing more
} else if(srcLength<-1) {
errorCode=U_ILLEGAL_ARGUMENT_ERROR;
} else {
// get input length
if(srcLength==-1) {
srcLength = static_cast<int32_t>(uprv_strlen(src));
}
if(srcLength>0) {
if (cnv != nullptr) {
// use the provided converter
ucnv_resetToUnicode(cnv);
doCodepageCreate(src, srcLength, cnv, errorCode);
} else {
// use the default converter
cnv=u_getDefaultConverter(&errorCode);
doCodepageCreate(src, srcLength, cnv, errorCode);
u_releaseDefaultConverter(cnv);
}
}
}
if(U_FAILURE(errorCode)) {
setToBogus();
}
}
}
//========================================
// Codeset conversion
//========================================
#if !U_CHARSET_IS_UTF8
int32_t
UnicodeString::extract(int32_t start,
int32_t length,
char *target,
uint32_t dstSize) const {
return extract(start, length, target, dstSize, 0);
}
// else see unistr.cpp
#endif
int32_t
UnicodeString::extract(int32_t start,
int32_t length,
char *target,
uint32_t dstSize,
const char *codepage) const
{
// if the arguments are illegal, then do nothing
if (/*dstSize < 0 || */(dstSize > 0 && target == nullptr)) {
return 0;
}
// pin the indices to legal values
pinIndices(start, length);
// We need to cast dstSize to int32_t for all subsequent code.
// I don't know why the API was defined with uint32_t but we are stuck with it.
// Also, dstSize==0xffffffff means "unlimited" but if we use target+dstSize
// as a limit in some functions, it may wrap around and yield a pointer
// that compares less-than target.
int32_t capacity;
if(dstSize < 0x7fffffff) {
// Assume that the capacity is real and a limit pointer won't wrap around.
capacity = static_cast<int32_t>(dstSize);
} else {
// Pin the capacity so that a limit pointer does not wrap around.
char* targetLimit = static_cast<char*>(U_MAX_PTR(target));
// U_MAX_PTR(target) returns a targetLimit that is at most 0x7fffffff
// greater than target and does not wrap around the top of the address space.
capacity = static_cast<int32_t>(targetLimit - target);
}
// create the converter
UConverter *converter;
UErrorCode status = U_ZERO_ERROR;
// just write the NUL if the string length is 0
if(length == 0) {
return u_terminateChars(target, capacity, 0, &status);
}
// if the codepage is the default, use our cache
// if it is an empty string, then use the "invariant character" conversion
if (codepage == nullptr) {
const char *defaultName = ucnv_getDefaultName();
if(UCNV_FAST_IS_UTF8(defaultName)) {
return toUTF8(start, length, target, capacity);
}
converter = u_getDefaultConverter(&status);
} else if (*codepage == 0) {
// use the "invariant characters" conversion
int32_t destLength;
if(length <= capacity) {
destLength = length;
} else {
destLength = capacity;
}
u_UCharsToChars(getArrayStart() + start, target, destLength);
return u_terminateChars(target, capacity, length, &status);
} else {
converter = ucnv_open(codepage, &status);
}
length = doExtract(start, length, target, capacity, converter, status);
// close the converter
if (codepage == nullptr) {
u_releaseDefaultConverter(converter);
} else {
ucnv_close(converter);
}
return length;
}
int32_t
UnicodeString::extract(char *dest, int32_t destCapacity,
UConverter *cnv,
UErrorCode &errorCode) const
{
if(U_FAILURE(errorCode)) {
return 0;
}
if (isBogus() || destCapacity < 0 || (destCapacity > 0 && dest == nullptr)) {
errorCode=U_ILLEGAL_ARGUMENT_ERROR;
return 0;
}
// nothing to do?
if(isEmpty()) {
return u_terminateChars(dest, destCapacity, 0, &errorCode);
}
// get the converter
UBool isDefaultConverter;
if (cnv == nullptr) {
isDefaultConverter=true;
cnv=u_getDefaultConverter(&errorCode);
if(U_FAILURE(errorCode)) {
return 0;
}
} else {
isDefaultConverter=false;
ucnv_resetFromUnicode(cnv);
}
// convert
int32_t len=doExtract(0, length(), dest, destCapacity, cnv, errorCode);
// release the converter
if(isDefaultConverter) {
u_releaseDefaultConverter(cnv);
}
return len;
}
int32_t
UnicodeString::doExtract(int32_t start, int32_t length,
char *dest, int32_t destCapacity,
UConverter *cnv,
UErrorCode &errorCode) const
{
if(U_FAILURE(errorCode)) {
if(destCapacity!=0) {
*dest=0;
}
return 0;
}
const char16_t *src=getArrayStart()+start, *srcLimit=src+length;
char *originalDest=dest;
const char *destLimit;
if(destCapacity==0) {
destLimit=dest=nullptr;
} else if(destCapacity==-1) {
// Pin the limit to U_MAX_PTR if the "magic" destCapacity is used.
destLimit = static_cast<char*>(U_MAX_PTR(dest));
// for NUL-termination, translate into highest int32_t
destCapacity=0x7fffffff;
} else {
destLimit=dest+destCapacity;
}
// perform the conversion
ucnv_fromUnicode(cnv, &dest, destLimit, &src, srcLimit, nullptr, true, &errorCode);
length = static_cast<int32_t>(dest - originalDest);
// if an overflow occurs, then get the preflighting length
if(errorCode==U_BUFFER_OVERFLOW_ERROR) {
char buffer[1024];
destLimit=buffer+sizeof(buffer);
do {
dest=buffer;
errorCode=U_ZERO_ERROR;
ucnv_fromUnicode(cnv, &dest, destLimit, &src, srcLimit, nullptr, true, &errorCode);
length += static_cast<int32_t>(dest - buffer);
} while(errorCode==U_BUFFER_OVERFLOW_ERROR);
}
return u_terminateChars(originalDest, destCapacity, length, &errorCode);
}
void
UnicodeString::doCodepageCreate(const char *codepageData,
int32_t dataLength,
const char *codepage)
{
// if there's nothing to convert, do nothing
if (codepageData == nullptr || dataLength == 0 || dataLength < -1) {
return;
}
if(dataLength == -1) {
dataLength = static_cast<int32_t>(uprv_strlen(codepageData));
}
UErrorCode status = U_ZERO_ERROR;
// create the converter
// if the codepage is the default, use our cache
// if it is an empty string, then use the "invariant character" conversion
UConverter *converter;
if (codepage == nullptr) {
const char *defaultName = ucnv_getDefaultName();
if(UCNV_FAST_IS_UTF8(defaultName)) {
setToUTF8(StringPiece(codepageData, dataLength));
return;
}
converter = u_getDefaultConverter(&status);
} else if (*codepage == 0) {
// use the "invariant characters" conversion
if(cloneArrayIfNeeded(dataLength, dataLength, false)) {
u_charsToUChars(codepageData, getArrayStart(), dataLength);
setLength(dataLength);
} else {
setToBogus();
}
return;
} else {
converter = ucnv_open(codepage, &status);
}
// if we failed, set the appropriate flags and return
if(U_FAILURE(status)) {
setToBogus();
return;
}
// perform the conversion
doCodepageCreate(codepageData, dataLength, converter, status);
if(U_FAILURE(status)) {
setToBogus();
}
// close the converter
if (codepage == nullptr) {
u_releaseDefaultConverter(converter);
} else {
ucnv_close(converter);
}
}
void
UnicodeString::doCodepageCreate(const char *codepageData,
int32_t dataLength,
UConverter *converter,
UErrorCode &status)
{
if(U_FAILURE(status)) {
return;
}
// set up the conversion parameters
const char *mySource = codepageData;
const char *mySourceEnd = mySource + dataLength;
char16_t *array, *myTarget;
// estimate the size needed:
int32_t arraySize;
if(dataLength <= US_STACKBUF_SIZE) {
// try to use the stack buffer
arraySize = US_STACKBUF_SIZE;
} else {
// 1.25 char16_t's per source byte should cover most cases
arraySize = dataLength + (dataLength >> 2);
}
// we do not care about the current contents
UBool doCopyArray = false;
for(;;) {
if(!cloneArrayIfNeeded(arraySize, arraySize, doCopyArray)) {
setToBogus();
break;
}
// perform the conversion
array = getArrayStart();
myTarget = array + length();
ucnv_toUnicode(converter, &myTarget, array + getCapacity(),
&mySource, mySourceEnd, nullptr, true, &status);
// update the conversion parameters
setLength(static_cast<int32_t>(myTarget - array));
// allocate more space and copy data, if needed
if(status == U_BUFFER_OVERFLOW_ERROR) {
// reset the error code
status = U_ZERO_ERROR;
// keep the previous conversion results
doCopyArray = true;
// estimate the new size needed, larger than before
// try 2 char16_t's per remaining source byte
arraySize = static_cast<int32_t>(length() + 2 * (mySourceEnd - mySource));
} else {
break;
}
}
}
U_NAMESPACE_END
#endif