/*
**********************************************************************
* Copyright (C) 1997-2015, International Business Machines
* Corporation and others. All Rights Reserved.
**********************************************************************
*
* File DIGITLST.CPP
*
* Modification History:
*
* Date Name Description
* 03/21/97 clhuang Converted from java.
* 03/21/97 clhuang Implemented with new APIs.
* 03/27/97 helena Updated to pass the simple test after code review.
* 03/31/97 aliu Moved isLONG_MIN to here, and fixed it.
* 04/15/97 aliu Changed MAX_COUNT to DBL_DIG. Changed Digit to char.
* Reworked representation by replacing fDecimalAt
* with fExponent.
* 04/16/97 aliu Rewrote set() and getDouble() to use sprintf/atof
* to do digit conversion.
* 09/09/97 aliu Modified for exponential notation support.
* 08/02/98 stephen Added nearest/even rounding
* Fixed bug in fitsIntoLong
******************************************************************************
*/
#include "digitlst.h"
#if !UCONFIG_NO_FORMATTING
#include "unicode/putil.h"
#include "charstr.h"
#include "cmemory.h"
#include "cstring.h"
#include "mutex.h"
#include "putilimp.h"
#include "uassert.h"
#include "digitinterval.h"
#include <stdlib.h>
#include <limits.h>
#include <string.h>
#include <stdio.h>
#include <limits>
// ***************************************************************************
// class DigitList
// A wrapper onto decNumber.
// Used to be standalone.
// ***************************************************************************
/**
* This is the zero digit. The base for the digits returned by getDigit()
* Note that it is the platform invariant digit, and is not Unicode.
*/
#define kZero '0'
/* Only for 32 bit numbers. Ignore the negative sign. */
//static const char LONG_MIN_REP[] = "2147483648";
//static const char I64_MIN_REP[] = "9223372036854775808";
U_NAMESPACE_BEGIN
// -------------------------------------
// default constructor
DigitList::DigitList()
{
uprv_decContextDefault(&fContext, DEC_INIT_BASE);
fContext.traps = 0;
uprv_decContextSetRounding(&fContext, DEC_ROUND_HALF_EVEN);
fContext.digits = fStorage.getCapacity();
fDecNumber = fStorage.getAlias();
uprv_decNumberZero(fDecNumber);
internalSetDouble(0.0);
}
// -------------------------------------
DigitList::~DigitList()
{
}
// -------------------------------------
// copy constructor
DigitList::DigitList(const DigitList &other)
{
fDecNumber = fStorage.getAlias();
*this = other;
}
// -------------------------------------
// assignment operator
DigitList&
DigitList::operator=(const DigitList& other)
{
if (this != &other)
{
uprv_memcpy(&fContext, &other.fContext, sizeof(decContext));
if (other.fStorage.getCapacity() > fStorage.getCapacity()) {
fDecNumber = fStorage.resize(other.fStorage.getCapacity());
}
// Always reset the fContext.digits, even if fDecNumber was not reallocated,
// because above we copied fContext from other.fContext.
fContext.digits = fStorage.getCapacity();
uprv_decNumberCopy(fDecNumber, other.fDecNumber);
{
// fDouble is lazily created and cached.
// Avoid potential races with that happening with other.fDouble
// while we are doing the assignment.
Mutex mutex;
if(other.fHave==kDouble) {
fUnion.fDouble = other.fUnion.fDouble;
} else if(other.fHave==kInt64) {
fUnion.fInt64 = other.fUnion.fInt64;
}
fHave = other.fHave;
}
}
return *this;
}
// -------------------------------------
// operator == (does not exactly match the old DigitList function)
UBool
DigitList::operator==(const DigitList& that) const
{
if (this == &that) {
return TRUE;
}
decNumber n; // Has space for only a none digit value.
decContext c;
uprv_decContextDefault(&c, DEC_INIT_BASE);
c.digits = 1;
c.traps = 0;
uprv_decNumberCompare(&n, this->fDecNumber, that.fDecNumber, &c);
UBool result = decNumberIsZero(&n);
return result;
}
// -------------------------------------
// comparison function. Returns
// Not Comparable : -2
// < : -1
// == : 0
// > : +1
int32_t DigitList::compare(const DigitList &other) {
decNumber result;
int32_t savedDigits = fContext.digits;
fContext.digits = 1;
uprv_decNumberCompare(&result, this->fDecNumber, other.fDecNumber, &fContext);
fContext.digits = savedDigits;
if (decNumberIsZero(&result)) {
return 0;
} else if (decNumberIsSpecial(&result)) {
return -2;
} else if (result.bits & DECNEG) {
return -1;
} else {
return 1;
}
}
// -------------------------------------
// Reduce - remove trailing zero digits.
void
DigitList::reduce() {
uprv_decNumberReduce(fDecNumber, fDecNumber, &fContext);
}
// -------------------------------------
// trim - remove trailing fraction zero digits.
void
DigitList::trim() {
uprv_decNumberTrim(fDecNumber);
}
// -------------------------------------
// Resets the digit list; sets all the digits to zero.
void
DigitList::clear()
{
uprv_decNumberZero(fDecNumber);
uprv_decContextSetRounding(&fContext, DEC_ROUND_HALF_EVEN);
internalSetDouble(0.0);
}
/**
* Formats a int64_t number into a base 10 string representation, and NULL terminates it.
* @param number The number to format
* @param outputStr The string to output to. Must be at least MAX_DIGITS+2 in length (21),
* to hold the longest int64_t value.
* @return the number of digits written, not including the sign.
*/
static int32_t
formatBase10(int64_t number, char *outputStr) {
// The number is output backwards, starting with the LSD.
// Fill the buffer from the far end. After the number is complete,
// slide the string contents to the front.
const int32_t MAX_IDX = MAX_DIGITS+2;
int32_t destIdx = MAX_IDX;
outputStr[--destIdx] = 0;
int64_t n = number;
if (number < 0) { // Negative numbers are slightly larger than a postive
outputStr[--destIdx] = (char)(-(n % 10) + kZero);
n /= -10;
}
do {
outputStr[--destIdx] = (char)(n % 10 + kZero);
n /= 10;
} while (n > 0);
if (number < 0) {
outputStr[--destIdx] = '-';
}
// Slide the number to the start of the output str
U_ASSERT(destIdx >= 0);
int32_t length = MAX_IDX - destIdx;
uprv_memmove(outputStr, outputStr+MAX_IDX-length, length);
return length;
}
// -------------------------------------
//
// setRoundingMode()
// For most modes, the meaning and names are the same between the decNumber library
// (which DigitList follows) and the ICU Formatting Rounding Mode values.
// The flag constants are different, however.
//
// Note that ICU's kRoundingUnnecessary is not implemented directly by DigitList.
// This mode, inherited from Java, means that numbers that would not format exactly
// will return an error when formatting is attempted.
void
DigitList::setRoundingMode(DecimalFormat::ERoundingMode m) {
enum rounding r;
switch (m) {
case DecimalFormat::kRoundCeiling: r = DEC_ROUND_CEILING; break;
case DecimalFormat::kRoundFloor: r = DEC_ROUND_FLOOR; break;
case DecimalFormat::kRoundDown: r = DEC_ROUND_DOWN; break;
case DecimalFormat::kRoundUp: r = DEC_ROUND_UP; break;
case DecimalFormat::kRoundHalfEven: r = DEC_ROUND_HALF_EVEN; break;
case DecimalFormat::kRoundHalfDown: r = DEC_ROUND_HALF_DOWN; break;
case DecimalFormat::kRoundHalfUp: r = DEC_ROUND_HALF_UP; break;
case DecimalFormat::kRoundUnnecessary: r = DEC_ROUND_HALF_EVEN; break;
default:
// TODO: how to report the problem?
// Leave existing mode unchanged.
r = uprv_decContextGetRounding(&fContext);
}
uprv_decContextSetRounding(&fContext, r);
}
// -------------------------------------
void
DigitList::setPositive(UBool s) {
if (s) {
fDecNumber->bits &= ~DECNEG;
} else {
fDecNumber->bits |= DECNEG;
}
internalClear();
}
// -------------------------------------
void
DigitList::setDecimalAt(int32_t d) {
U_ASSERT((fDecNumber->bits & DECSPECIAL) == 0); // Not Infinity or NaN
U_ASSERT(d-1>-999999999);
U_ASSERT(d-1< 999999999);
int32_t adjustedDigits = fDecNumber->digits;
if (decNumberIsZero(fDecNumber)) {
// Account for difference in how zero is represented between DigitList & decNumber.
adjustedDigits = 0;
}
fDecNumber->exponent = d - adjustedDigits;
internalClear();
}
int32_t
DigitList::getDecimalAt() {
U_ASSERT((fDecNumber->bits & DECSPECIAL) == 0); // Not Infinity or NaN
if (decNumberIsZero(fDecNumber) || ((fDecNumber->bits & DECSPECIAL) != 0)) {
return fDecNumber->exponent; // Exponent should be zero for these cases.
}
return fDecNumber->exponent + fDecNumber->digits;
}
void
DigitList::setCount(int32_t c) {
U_ASSERT(c <= fContext.digits);
if (c == 0) {
// For a value of zero, DigitList sets all fields to zero, while
// decNumber keeps one digit (with that digit being a zero)
c = 1;
fDecNumber->lsu[0] = 0;
}
fDecNumber->digits = c;
internalClear();
}
int32_t
DigitList::getCount() const {
if (decNumberIsZero(fDecNumber) && fDecNumber->exponent==0) {
// The extra test for exponent==0 is needed because parsing sometimes appends
// zero digits. It's bogus, decimalFormatter parsing needs to be cleaned up.
return 0;
} else {
return fDecNumber->digits;
}
}
void
DigitList::setDigit(int32_t i, char v) {
int32_t count = fDecNumber->digits;
U_ASSERT(i<count);
U_ASSERT(v>='0' && v<='9');
v &= 0x0f;
fDecNumber->lsu[count-i-1] = v;
internalClear();
}
char
DigitList::getDigit(int32_t i) {
int32_t count = fDecNumber->digits;
U_ASSERT(i<count);
return fDecNumber->lsu[count-i-1] + '0';
}
// copied from DigitList::getDigit()
uint8_t
DigitList::getDigitValue(int32_t i) {
int32_t count = fDecNumber->digits;
U_ASSERT(i<count);
return fDecNumber->lsu[count-i-1];
}
// -------------------------------------
// Appends the digit to the digit list if it's not out of scope.
// Ignores the digit, otherwise.
//
// This function is horribly inefficient to implement with decNumber because
// the digits are stored least significant first, which requires moving all
// existing digits down one to make space for the new one to be appended.
//
void
DigitList::append(char digit)
{
U_ASSERT(digit>='0' && digit<='9');
// Ignore digits which exceed the precision we can represent
// And don't fix for larger precision. Fix callers instead.
if (decNumberIsZero(fDecNumber)) {
// Zero needs to be special cased because of the difference in the way
// that the old DigitList and decNumber represent it.
// digit cout was zero for digitList, is one for decNumber
fDecNumber->lsu[0] = digit & 0x0f;
fDecNumber->digits = 1;
fDecNumber->exponent--; // To match the old digit list implementation.
} else {
int32_t nDigits = fDecNumber->digits;
if (nDigits < fContext.digits) {
int i;
for (i=nDigits; i>0; i--) {
fDecNumber->lsu[i] = fDecNumber->lsu[i-1];
}
fDecNumber->lsu[0] = digit & 0x0f;
fDecNumber->digits++;
// DigitList emulation - appending doesn't change the magnitude of existing
// digits. With decNumber's decimal being after the
// least signficant digit, we need to adjust the exponent.
fDecNumber->exponent--;
}
}
internalClear();
}
char DigitList::getStrtodDecimalSeparator() {
// TODO: maybe use andy's pthread once.
static char gDecimal = 0;
char result;
{
Mutex mutex;
result = gDecimal;;
if (result == 0) {
// We need to know the decimal separator character that will be used with strtod().
// Depends on the C runtime global locale.
// Most commonly is '.'
// TODO: caching could fail if the global locale is changed on the fly.
char rep[MAX_DIGITS];
sprintf(rep, "%+1.1f", 1.0);
result = rep[2];
gDecimal = result;;
}
}
return result;
}
// -------------------------------------
/**
* Currently, getDouble() depends on strtod() to do its conversion.
*
* WARNING!!
* This is an extremely costly function. ~1/2 of the conversion time
* can be linked to this function.
*/
double
DigitList::getDouble() const
{
static char gDecimal = 0;
char decimalSeparator;
{
Mutex mutex;
if (fHave == kDouble) {
return fUnion.fDouble;
} else if(fHave == kInt64) {
return (double)fUnion.fInt64;
}
decimalSeparator = gDecimal;
}
if (decimalSeparator == 0) {
// We need to know the decimal separator character that will be used with strtod().
// Depends on the C runtime global locale.
// Most commonly is '.'
// TODO: caching could fail if the global locale is changed on the fly.
char rep[MAX_DIGITS];
sprintf(rep, "%+1.1f", 1.0);
decimalSeparator = rep[2];
}
double tDouble = 0.0;
if (isZero()) {
tDouble = 0.0;
if (decNumberIsNegative(fDecNumber)) {
tDouble /= -1;
}
} else if (isInfinite()) {
if (std::numeric_limits<double>::has_infinity) {
tDouble = std::numeric_limits<double>::infinity();
} else {
tDouble = std::numeric_limits<double>::max();
}
if (!isPositive()) {
tDouble = -tDouble; //this was incorrectly "-fDouble" originally.
}
} else {
MaybeStackArray<char, MAX_DBL_DIGITS+18> s;
// Note: 14 is a magic constant from the decNumber library documentation,
// the max number of extra characters beyond the number of digits
// needed to represent the number in string form. Add a few more
// for the additional digits we retain.
// Round down to appx. double precision, if the number is longer than that.
// Copy the number first, so that we don't modify the original.
if (getCount() > MAX_DBL_DIGITS + 3) {
DigitList numToConvert(*this);
numToConvert.reduce(); // Removes any trailing zeros, so that digit count is good.
numToConvert.round(MAX_DBL_DIGITS+3);
uprv_decNumberToString(numToConvert.fDecNumber, s.getAlias());
// TODO: how many extra digits should be included for an accurate conversion?
} else {
uprv_decNumberToString(this->fDecNumber, s.getAlias());
}
U_ASSERT(uprv_strlen(&s[0]) < MAX_DBL_DIGITS+18);
if (decimalSeparator != '.') {
char *decimalPt = strchr(s.getAlias(), '.');
if (decimalPt != NULL) {
*decimalPt = decimalSeparator;
}
}
char *end = NULL;
tDouble = uprv_strtod(s.getAlias(), &end);
}
{
Mutex mutex;
DigitList *nonConstThis = const_cast<DigitList *>(this);
nonConstThis->internalSetDouble(tDouble);
gDecimal = decimalSeparator;
}
return tDouble;
}
// -------------------------------------
/**
* convert this number to an int32_t. Round if there is a fractional part.
* Return zero if the number cannot be represented.
*/
int32_t DigitList::getLong() /*const*/
{
int32_t result = 0;
if (getUpperExponent() > 10) {
// Overflow, absolute value too big.
return result;
}
if (fDecNumber->exponent != 0) {
// Force to an integer, with zero exponent, rounding if necessary.
// (decNumberToInt32 will only work if the exponent is exactly zero.)
DigitList copy(*this);
DigitList zero;
uprv_decNumberQuantize(copy.fDecNumber, copy.fDecNumber, zero.fDecNumber, &fContext);
result = uprv_decNumberToInt32(copy.fDecNumber, &fContext);
} else {
result = uprv_decNumberToInt32(fDecNumber, &fContext);
}
return result;
}
/**
* convert this number to an int64_t. Truncate if there is a fractional part.
* Return zero if the number cannot be represented.
*/
int64_t DigitList::getInt64() /*const*/ {
if(fHave==kInt64) {
return fUnion.fInt64;
}
// Truncate if non-integer.
// Return 0 if out of range.
// Range of in64_t is -9223372036854775808 to 9223372036854775807 (19 digits)
//
if (getUpperExponent() > 19) {
// Overflow, absolute value too big.
return 0;
}
// The number of integer digits may differ from the number of digits stored
// in the decimal number.
// for 12.345 numIntDigits = 2, number->digits = 5
// for 12E4 numIntDigits = 6, number->digits = 2
// The conversion ignores the fraction digits in the first case,
// and fakes up extra zero digits in the second.
// TODO: It would be faster to store a table of powers of ten to multiply by
// instead of looping over zero digits, multiplying each time.
int32_t numIntDigits = getUpperExponent();
uint64_t value = 0;
for (int32_t i = 0; i < numIntDigits; i++) {
// Loop is iterating over digits starting with the most significant.
// Numbers are stored with the least significant digit at index zero.
int32_t digitIndex = fDecNumber->digits - i - 1;
int32_t v = (digitIndex >= 0) ? fDecNumber->lsu[digitIndex] : 0;
value = value * (uint64_t)10 + (uint64_t)v;
}
if (decNumberIsNegative(fDecNumber)) {
value = ~value;
value += 1;
}
int64_t svalue = (int64_t)value;
// Check overflow. It's convenient that the MSD is 9 only on overflow, the amount of
// overflow can't wrap too far. The test will also fail -0, but
// that does no harm; the right answer is 0.
if (numIntDigits == 19) {
if (( decNumberIsNegative(fDecNumber) && svalue>0) ||
(!decNumberIsNegative(fDecNumber) && svalue<0)) {
svalue = 0;
}
}
return svalue;
}
/**
* Return a string form of this number.
* Format is as defined by the decNumber library, for interchange of
* decimal numbers.
*/
void DigitList::getDecimal(CharString &str, UErrorCode &status) {
if (U_FAILURE(status)) {
return;
}
// A decimal number in string form can, worst case, be 14 characters longer
// than the number of digits. So says the decNumber library doc.
int32_t maxLength = fDecNumber->digits + 14;
int32_t capacity = 0;
char *buffer = str.clear().getAppendBuffer(maxLength, 0, capacity, status);
if (U_FAILURE(status)) {
return; // Memory allocation error on growing the string.
}
U_ASSERT(capacity >= maxLength);
uprv_decNumberToString(this->fDecNumber, buffer);
U_ASSERT((int32_t)uprv_strlen(buffer) <= maxLength);
str.append(buffer, -1, status);
}
/**
* Return true if this is an integer value that can be held
* by an int32_t type.
*/
UBool
DigitList::fitsIntoLong(UBool ignoreNegativeZero) /*const*/
{
if (decNumberIsSpecial(this->fDecNumber)) {
// NaN or Infinity. Does not fit in int32.
return FALSE;
}
uprv_decNumberTrim(this->fDecNumber);
if (fDecNumber->exponent < 0) {
// Number contains fraction digits.
return FALSE;
}
if (decNumberIsZero(this->fDecNumber) && !ignoreNegativeZero &&
(fDecNumber->bits & DECNEG) != 0) {
// Negative Zero, not ingored. Cannot represent as a long.
return FALSE;
}
if (getUpperExponent() < 10) {
// The number is 9 or fewer digits.
// The max and min int32 are 10 digts, so this number fits.
// This is the common case.
return TRUE;
}
// TODO: Should cache these constants; construction is relatively costly.
// But not of huge consequence; they're only needed for 10 digit ints.
UErrorCode status = U_ZERO_ERROR;
DigitList min32; min32.set("-2147483648", status);
if (this->compare(min32) < 0) {
return FALSE;
}
DigitList max32; max32.set("2147483647", status);
if (this->compare(max32) > 0) {
return FALSE;
}
if (U_FAILURE(status)) {
return FALSE;
}
return true;
}
/**
* Return true if the number represented by this object can fit into
* a long.
*/
UBool
DigitList::fitsIntoInt64(UBool ignoreNegativeZero) /*const*/
{
if (decNumberIsSpecial(this->fDecNumber)) {
// NaN or Infinity. Does not fit in int32.
return FALSE;
}
uprv_decNumberTrim(this->fDecNumber);
if (fDecNumber->exponent < 0) {
// Number contains fraction digits.
return FALSE;
}
if (decNumberIsZero(this->fDecNumber) && !ignoreNegativeZero &&
(fDecNumber->bits & DECNEG) != 0) {
// Negative Zero, not ingored. Cannot represent as a long.
return FALSE;
}
if (getUpperExponent() < 19) {
// The number is 18 or fewer digits.
// The max and min int64 are 19 digts, so this number fits.
// This is the common case.
return TRUE;
}
// TODO: Should cache these constants; construction is relatively costly.
// But not of huge consequence; they're only needed for 19 digit ints.
UErrorCode status = U_ZERO_ERROR;
DigitList min64; min64.set("-9223372036854775808", status);
if (this->compare(min64) < 0) {
return FALSE;
}
DigitList max64; max64.set("9223372036854775807", status);
if (this->compare(max64) > 0) {
return FALSE;
}
if (U_FAILURE(status)) {
return FALSE;
}
return true;
}
// -------------------------------------
void
DigitList::set(int32_t source)
{
set((int64_t)source);
internalSetDouble(source);
}
// -------------------------------------
/**
* Set an int64, via decnumber
*/
void
DigitList::set(int64_t source)
{
char str[MAX_DIGITS+2]; // Leave room for sign and trailing nul.
formatBase10(source, str);
U_ASSERT(uprv_strlen(str) < sizeof(str));
uprv_decNumberFromString(fDecNumber, str, &fContext);
internalSetDouble(static_cast<double>(source));
}
/**
* Set an int64, with no decnumber
*/
void
DigitList::setInteger(int64_t source)
{
fDecNumber=NULL;
internalSetInt64(source);
}
// -------------------------------------
/**
* Set the DigitList from a decimal number string.
*
* The incoming string _must_ be nul terminated, even though it is arriving
* as a StringPiece because that is what the decNumber library wants.
* We can get away with this for an internal function; it would not
* be acceptable for a public API.
*/
void
DigitList::set(const StringPiece &source, UErrorCode &status, uint32_t /*fastpathBits*/) {
if (U_FAILURE(status)) {
return;
}
#if 0
if(fastpathBits==(kFastpathOk|kNoDecimal)) {
int32_t size = source.size();
const char *data = source.data();
int64_t r = 0;
int64_t m = 1;
// fast parse
while(size>0) {
char ch = data[--size];
if(ch=='+') {
break;
} else if(ch=='-') {
r = -r;
break;
} else {
int64_t d = ch-'0';
//printf("CH[%d]=%c, %d, *=%d\n", size,ch, (int)d, (int)m);
r+=(d)*m;
m *= 10;
}
}
//printf("R=%d\n", r);
set(r);
} else
#endif
{
// Figure out a max number of digits to use during the conversion, and
// resize the number up if necessary.
int32_t numDigits = source.length();
if (numDigits > fContext.digits) {
// fContext.digits == fStorage.getCapacity()
decNumber *t = fStorage.resize(numDigits, fStorage.getCapacity());
if (t == NULL) {
status = U_MEMORY_ALLOCATION_ERROR;
return;
}
fDecNumber = t;
fContext.digits = numDigits;
}
fContext.status = 0;
uprv_decNumberFromString(fDecNumber, source.data(), &fContext);
if ((fContext.status & DEC_Conversion_syntax) != 0) {
status = U_DECIMAL_NUMBER_SYNTAX_ERROR;
}
}
internalClear();
}
/**
* Set the digit list to a representation of the given double value.
* This method supports both fixed-point and exponential notation.
* @param source Value to be converted.
*/
void
DigitList::set(double source)
{
// for now, simple implementation; later, do proper IEEE stuff
char rep[MAX_DIGITS + 8]; // Extra space for '+', '.', e+NNN, and '\0' (actually +8 is enough)
// Generate a representation of the form /[+-][0-9].[0-9]+e[+-][0-9]+/
// Can also generate /[+-]nan/ or /[+-]inf/
// TODO: Use something other than sprintf() here, since it's behavior is somewhat platform specific.
// That is why infinity is special cased here.
if (uprv_isInfinite(source)) {
if (uprv_isNegativeInfinity(source)) {
uprv_strcpy(rep,"-inf"); // Handle negative infinity
} else {
uprv_strcpy(rep,"inf");
}
} else {
sprintf(rep, "%+1.*e", MAX_DBL_DIGITS - 1, source);
}
U_ASSERT(uprv_strlen(rep) < sizeof(rep));
// uprv_decNumberFromString() will parse the string expecting '.' as a
// decimal separator, however sprintf() can use ',' in certain locales.
// Overwrite a ',' with '.' here before proceeding.
char *decimalSeparator = strchr(rep, ',');
if (decimalSeparator != NULL) {
*decimalSeparator = '.';
}
// Create a decNumber from the string.
uprv_decNumberFromString(fDecNumber, rep, &fContext);
uprv_decNumberTrim(fDecNumber);
internalSetDouble(source);
}
// -------------------------------------
/*
* Multiply
* The number will be expanded if need be to retain full precision.
* In practice, for formatting, multiply is by 10, 100 or 1000, so more digits
* will not be required for this use.
*/
void
DigitList::mult(const DigitList &other, UErrorCode &status) {
if (U_FAILURE(status)) {
return;
}
fContext.status = 0;
int32_t requiredDigits = this->digits() + other.digits();
if (requiredDigits > fContext.digits) {
reduce(); // Remove any trailing zeros
int32_t requiredDigits = this->digits() + other.digits();
ensureCapacity(requiredDigits, status);
}
uprv_decNumberMultiply(fDecNumber, fDecNumber, other.fDecNumber, &fContext);
internalClear();
}
// -------------------------------------
/*
* Divide
* The number will _not_ be expanded for inexact results.
* TODO: probably should expand some, for rounding increments that
* could add a few digits, e.g. .25, but not expand arbitrarily.
*/
void
DigitList::div(const DigitList &other, UErrorCode &status) {
if (U_FAILURE(status)) {
return;
}
uprv_decNumberDivide(fDecNumber, fDecNumber, other.fDecNumber, &fContext);
internalClear();
}
// -------------------------------------
/*
* ensureCapacity. Grow the digit storage for the number if it's less than the requested
* amount. Never reduce it. Available size is kept in fContext.digits.
*/
void
DigitList::ensureCapacity(int32_t requestedCapacity, UErrorCode &status) {
if (U_FAILURE(status)) {
return;
}
if (requestedCapacity <= 0) {
status = U_ILLEGAL_ARGUMENT_ERROR;
return;
}
if (requestedCapacity > DEC_MAX_DIGITS) {
// Don't report an error for requesting too much.
// Arithemetic Results will be rounded to what can be supported.
// At 999,999,999 max digits, exceeding the limit is not too likely!
requestedCapacity = DEC_MAX_DIGITS;
}
if (requestedCapacity > fContext.digits) {
decNumber *newBuffer = fStorage.resize(requestedCapacity, fStorage.getCapacity());
if (newBuffer == NULL) {
status = U_MEMORY_ALLOCATION_ERROR;
return;
}
fContext.digits = requestedCapacity;
fDecNumber = newBuffer;
}
}
// -------------------------------------
/**
* Round the representation to the given number of digits.
* @param maximumDigits The maximum number of digits to be shown.
* Upon return, count will be less than or equal to maximumDigits.
*/
void
DigitList::round(int32_t maximumDigits)
{
reduce();
if (maximumDigits >= fDecNumber->digits) {
return;
}
int32_t savedDigits = fContext.digits;
fContext.digits = maximumDigits;
uprv_decNumberPlus(fDecNumber, fDecNumber, &fContext);
fContext.digits = savedDigits;
uprv_decNumberTrim(fDecNumber);
reduce();
internalClear();
}
void
DigitList::roundFixedPoint(int32_t maximumFractionDigits) {
reduce(); // Remove trailing zeros.
if (fDecNumber->exponent >= -maximumFractionDigits) {
return;
}
decNumber scale; // Dummy decimal number, but with the desired number of
uprv_decNumberZero(&scale); // fraction digits.
scale.exponent = -maximumFractionDigits;
scale.lsu[0] = 1;
uprv_decNumberQuantize(fDecNumber, fDecNumber, &scale, &fContext);
reduce();
internalClear();
}
// -------------------------------------
void
DigitList::toIntegralValue() {
uprv_decNumberToIntegralValue(fDecNumber, fDecNumber, &fContext);
}
// -------------------------------------
UBool
DigitList::isZero() const
{
return decNumberIsZero(fDecNumber);
}
// -------------------------------------
int32_t
DigitList::getUpperExponent() const {
return fDecNumber->digits + fDecNumber->exponent;
}
DigitInterval &
DigitList::getSmallestInterval(DigitInterval &result) const {
result.setLeastSignificantInclusive(fDecNumber->exponent);
result.setMostSignificantExclusive(getUpperExponent());
return result;
}
uint8_t
DigitList::getDigitByExponent(int32_t exponent) const {
int32_t idx = exponent - fDecNumber->exponent;
if (idx < 0 || idx >= fDecNumber->digits) {
return 0;
}
return fDecNumber->lsu[idx];
}
void
DigitList::appendDigitsTo(CharString &str, UErrorCode &status) const {
str.append((const char *) fDecNumber->lsu, fDecNumber->digits, status);
}
void
DigitList::roundAtExponent(int32_t exponent, int32_t maxSigDigits) {
reduce();
if (maxSigDigits < fDecNumber->digits) {
int32_t minExponent = getUpperExponent() - maxSigDigits;
if (exponent < minExponent) {
exponent = minExponent;
}
}
if (exponent <= fDecNumber->exponent) {
return;
}
int32_t digits = getUpperExponent() - exponent;
if (digits > 0) {
round(digits);
} else {
roundFixedPoint(-exponent);
}
}
void
DigitList::quantize(const DigitList &quantity, UErrorCode &status) {
if (U_FAILURE(status)) {
return;
}
div(quantity, status);
roundAtExponent(0);
mult(quantity, status);
reduce();
}
int32_t
DigitList::getScientificExponent(
int32_t minIntDigitCount, int32_t exponentMultiplier) const {
// The exponent for zero is always zero.
if (isZero()) {
return 0;
}
int32_t intDigitCount = getUpperExponent();
int32_t exponent;
if (intDigitCount >= minIntDigitCount) {
int32_t maxAdjustment = intDigitCount - minIntDigitCount;
exponent = (maxAdjustment / exponentMultiplier) * exponentMultiplier;
} else {
int32_t minAdjustment = minIntDigitCount - intDigitCount;
exponent = ((minAdjustment + exponentMultiplier - 1) / exponentMultiplier) * -exponentMultiplier;
}
return exponent;
}
int32_t
DigitList::toScientific(
int32_t minIntDigitCount, int32_t exponentMultiplier) {
int32_t exponent = getScientificExponent(
minIntDigitCount, exponentMultiplier);
shiftDecimalRight(-exponent);
return exponent;
}
void
DigitList::shiftDecimalRight(int32_t n) {
fDecNumber->exponent += n;
internalClear();
}
U_NAMESPACE_END
#endif // #if !UCONFIG_NO_FORMATTING
//eof