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// Copyright (C) 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/*
* Copyright (C) 2016, International Business Machines
* Corporation and others. All Rights Reserved.
*
* file name: visibledigits.cpp
*/
#include <math.h>
#include "unicode/utypes.h"
#if !UCONFIG_NO_FORMATTING
#include "cstring.h"
#include "decNumber.h"
#include "digitlst.h"
#include "uassert.h"
#include "visibledigits.h"
static const int32_t kNegative = 1;
static const int32_t kInfinite = 2;
static const int32_t kNaN = 4;
U_NAMESPACE_BEGIN
void VisibleDigits::setNegative() {
fFlags |= kNegative;
}
void VisibleDigits::setNaN() {
fFlags |= kNaN;
}
void VisibleDigits::setInfinite() {
fFlags |= kInfinite;
}
void VisibleDigits::clear() {
fInterval.clear();
fDigits.clear();
fExponent = 0;
fFlags = 0;
fAbsIntValue = 0LL;
fAbsIntValueSet = FALSE;
fAbsDoubleValue = 0.0;
fAbsDoubleValueSet = FALSE;
}
UBool VisibleDigits::isNegative() const {
return (fFlags & kNegative);
}
UBool VisibleDigits::isNaN() const {
return (fFlags & kNaN);
}
UBool VisibleDigits::isInfinite() const {
return (fFlags & kInfinite);
}
int32_t VisibleDigits::getDigitByExponent(int32_t digitPos) const {
if (digitPos < fExponent || digitPos >= fExponent + fDigits.length()) {
return 0;
}
const char *ptr = fDigits.data();
return ptr[digitPos - fExponent];
}
UBool VisibleDigits::isOverMaxDigits() const {
return (fExponent + fDigits.length() > fInterval.getMostSignificantExclusive());
}
UBool VisibleDigits::isNaNOrInfinity() const {
return (fFlags & (kInfinite | kNaN)) != 0;
}
double VisibleDigits::computeAbsDoubleValue() const {
// Take care of NaN and infinity
if (isNaN()) {
return uprv_getNaN();
}
if (isInfinite()) {
return uprv_getInfinity();
}
// stack allocate a decNumber to hold MAX_DBL_DIGITS+3 significant digits
struct {
decNumber decNum;
char digits[MAX_DBL_DIGITS+3];
} decNumberWithStorage;
decNumber *numberPtr = &decNumberWithStorage.decNum;
int32_t mostSig = fInterval.getMostSignificantExclusive();
int32_t mostSigNonZero = fExponent + fDigits.length();
int32_t end = mostSig > mostSigNonZero ? mostSigNonZero : mostSig;
int32_t leastSig = fInterval.getLeastSignificantInclusive();
int32_t start = leastSig > fExponent ? leastSig : fExponent;
if (end <= start) {
return 0.0;
}
if (start < end - (MAX_DBL_DIGITS+3)) {
start = end - (MAX_DBL_DIGITS+3);
}
uint8_t *pos = numberPtr->lsu;
const char *src = &(fDigits.data()[start - fExponent]);
for (int32_t i = start; i < end; ++i) {
*pos++ = (uint8_t) (*src++);
}
numberPtr->exponent = start;
numberPtr->bits = 0;
numberPtr->digits = end - start;
char str[MAX_DBL_DIGITS+18];
uprv_decNumberToString(numberPtr, str);
U_ASSERT(uprv_strlen(str) < MAX_DBL_DIGITS+18);
char *unused = NULL;
return DigitList::decimalStrToDouble(str, &unused);
}
void VisibleDigits::getFixedDecimal(
double &source, int64_t &intValue, int64_t &f, int64_t &t, int32_t &v, UBool &hasIntValue) const {
source = 0.0;
intValue = 0;
f = 0;
t = 0;
v = 0;
hasIntValue = FALSE;
if (isNaNOrInfinity()) {
return;
}
// source
if (fAbsDoubleValueSet) {
source = fAbsDoubleValue;
} else {
source = computeAbsDoubleValue();
}
// visible decimal digits
v = fInterval.getFracDigitCount();
// intValue
// If we initialized from an int64 just use that instead of
// calculating
if (fAbsIntValueSet) {
intValue = fAbsIntValue;
} else {
int32_t startPos = fInterval.getMostSignificantExclusive();
if (startPos > 18) {
startPos = 18;
}
// process the integer digits
for (int32_t i = startPos - 1; i >= 0; --i) {
intValue = intValue * 10LL + getDigitByExponent(i);
}
if (intValue == 0LL && startPos > 0) {
intValue = 100000000000000000LL;
}
}
// f (decimal digits)
// skip over any leading 0's in fraction digits.
int32_t idx = -1;
for (; idx >= -v && getDigitByExponent(idx) == 0; --idx)
;
// Only process up to first 18 non zero fraction digits for decimalDigits
// since that is all we can fit into an int64.
for (int32_t i = idx; i >= -v && i > idx - 18; --i) {
f = f * 10LL + getDigitByExponent(i);
}
// If we have no decimal digits, we don't have an integer value
hasIntValue = (f == 0LL);
// t (decimal digits without trailing zeros)
t = f;
while (t > 0 && t % 10LL == 0) {
t /= 10;
}
}
U_NAMESPACE_END
#endif /* #if !UCONFIG_NO_FORMATTING */