scuffed-code/icu4c/source/i18n/digitlst.cpp
Steven R. Loomis 9077d5dc25 ICU-9449 Merge in decimal format performance improvements from branch.
Improvements to 'howExpensiveIs' benchmark test.
Use internal digitlist in Formattable (save mallocs).
Enable fastpath by default.
Enable internal API "parse all input", returning an error if all input was not consumed.

X-SVN-Rev: 32397
2012-09-17 19:03:01 +00:00

960 lines
29 KiB
C++

/*
**********************************************************************
* Copyright (C) 1997-2012, 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 <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";
static const uint8_t DIGIT_HAVE_NONE=0;
static const uint8_t DIGIT_HAVE_DOUBLE=1;
static const uint8_t DIGIT_HAVE_INT64=2;
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();
}
// -------------------------------------
/**
* 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 (fDecNumber->digits + fDecNumber->exponent > 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 (fDecNumber->digits + fDecNumber->exponent > 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 = fDecNumber->digits + fDecNumber->exponent;
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 (fDecNumber->digits + fDecNumber->exponent < 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 (fDecNumber->digits + fDecNumber->exponent < 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(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) {
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)
{
int32_t savedDigits = fContext.digits;
fContext.digits = maximumDigits;
uprv_decNumberPlus(fDecNumber, fDecNumber, &fContext);
fContext.digits = savedDigits;
uprv_decNumberTrim(fDecNumber);
internalClear();
}
void
DigitList::roundFixedPoint(int32_t maximumFractionDigits) {
trim(); // 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);
trim();
internalClear();
}
// -------------------------------------
void
DigitList::toIntegralValue() {
uprv_decNumberToIntegralValue(fDecNumber, fDecNumber, &fContext);
}
// -------------------------------------
UBool
DigitList::isZero() const
{
return decNumberIsZero(fDecNumber);
}
void * U_EXPORT2 DigitList::operator new(size_t /*size*/, void *stack, EStackMode /*mode*/) U_NO_THROW {
return stack;
}
U_NAMESPACE_END
#endif // #if !UCONFIG_NO_FORMATTING
//eof