office-gobmx/sal/rtl/math.cxx
Eike Rathke f19b4826c4 use ::std::swap() to reverse buffer
Change-Id: I7e18e57636416f0a3ed96c2fa3adc004fb3ba013
2016-01-14 20:53:31 +01:00

1127 lines
37 KiB
C++

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
* This file is part of the LibreOffice project.
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*
* This file incorporates work covered by the following license notice:
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed
* with this work for additional information regarding copyright
* ownership. The ASF licenses this file to you under the Apache
* License, Version 2.0 (the "License"); you may not use this file
* except in compliance with the License. You may obtain a copy of
* the License at http://www.apache.org/licenses/LICENSE-2.0 .
*/
#include "rtl/math.h"
#include "osl/diagnose.h"
#include "rtl/alloc.h"
#include "rtl/character.hxx"
#include "rtl/math.hxx"
#include "rtl/strbuf.h"
#include "rtl/string.h"
#include "rtl/ustrbuf.h"
#include "rtl/ustring.h"
#include "sal/mathconf.h"
#include "sal/types.h"
#include <algorithm>
#include <cassert>
#include <float.h>
#include <limits.h>
#include <math.h>
#include <stdlib.h>
static int const n10Count = 16;
static double const n10s[2][n10Count] = {
{ 1e1, 1e2, 1e3, 1e4, 1e5, 1e6, 1e7, 1e8,
1e9, 1e10, 1e11, 1e12, 1e13, 1e14, 1e15, 1e16 },
{ 1e-1, 1e-2, 1e-3, 1e-4, 1e-5, 1e-6, 1e-7, 1e-8,
1e-9, 1e-10, 1e-11, 1e-12, 1e-13, 1e-14, 1e-15, 1e-16 }
};
// return pow(10.0,nExp) optimized for exponents in the interval [-16,16]
static double getN10Exp( int nExp )
{
if ( nExp < 0 )
{
// && -nExp > 0 necessary for std::numeric_limits<int>::min()
// because -nExp = nExp
if ( -nExp <= n10Count && -nExp > 0 )
return n10s[1][-nExp-1];
else
return pow( 10.0, static_cast<double>( nExp ) );
}
else if ( nExp > 0 )
{
if ( nExp <= n10Count )
return n10s[0][nExp-1];
else
return pow( 10.0, static_cast<double>( nExp ) );
}
else // ( nExp == 0 )
return 1.0;
}
namespace {
double const nKorrVal[] = {
0, 9e-1, 9e-2, 9e-3, 9e-4, 9e-5, 9e-6, 9e-7, 9e-8,
9e-9, 9e-10, 9e-11, 9e-12, 9e-13, 9e-14, 9e-15
};
struct StringTraits
{
typedef sal_Char Char;
typedef rtl_String String;
static inline void createString(rtl_String ** pString,
sal_Char const * pChars, sal_Int32 nLen)
{
rtl_string_newFromStr_WithLength(pString, pChars, nLen);
}
static inline void createBuffer(rtl_String ** pBuffer,
sal_Int32 * pCapacity)
{
rtl_string_new_WithLength(pBuffer, *pCapacity);
}
static inline void appendChars(rtl_String ** pBuffer, sal_Int32 * pCapacity,
sal_Int32 * pOffset, sal_Char const * pChars,
sal_Int32 nLen)
{
assert(pChars != nullptr);
rtl_stringbuffer_insert(pBuffer, pCapacity, *pOffset, pChars, nLen);
*pOffset += nLen;
}
static inline void appendAscii(rtl_String ** pBuffer, sal_Int32 * pCapacity,
sal_Int32 * pOffset, sal_Char const * pStr,
sal_Int32 nLen)
{
assert(pStr != nullptr);
rtl_stringbuffer_insert(pBuffer, pCapacity, *pOffset, pStr, nLen);
*pOffset += nLen;
}
};
struct UStringTraits
{
typedef sal_Unicode Char;
typedef rtl_uString String;
static inline void createString(rtl_uString ** pString,
sal_Unicode const * pChars, sal_Int32 nLen)
{
rtl_uString_newFromStr_WithLength(pString, pChars, nLen);
}
static inline void createBuffer(rtl_uString ** pBuffer,
sal_Int32 * pCapacity)
{
rtl_uString_new_WithLength(pBuffer, *pCapacity);
}
static inline void appendChars(rtl_uString ** pBuffer,
sal_Int32 * pCapacity, sal_Int32 * pOffset,
sal_Unicode const * pChars, sal_Int32 nLen)
{
assert(pChars != nullptr);
rtl_uStringbuffer_insert(pBuffer, pCapacity, *pOffset, pChars, nLen);
*pOffset += nLen;
}
static inline void appendAscii(rtl_uString ** pBuffer,
sal_Int32 * pCapacity, sal_Int32 * pOffset,
sal_Char const * pStr, sal_Int32 nLen)
{
rtl_uStringbuffer_insert_ascii(pBuffer, pCapacity, *pOffset, pStr,
nLen);
*pOffset += nLen;
}
};
// Solaris C++ 5.2 compiler has problems when "StringT ** pResult" is
// "typename T::String ** pResult" instead:
template< typename T, typename StringT >
inline void doubleToString(StringT ** pResult,
sal_Int32 * pResultCapacity, sal_Int32 nResultOffset,
double fValue, rtl_math_StringFormat eFormat,
sal_Int32 nDecPlaces, typename T::Char cDecSeparator,
sal_Int32 const * pGroups,
typename T::Char cGroupSeparator,
bool bEraseTrailingDecZeros)
{
static double const nRoundVal[] = {
5.0e+0, 0.5e+0, 0.5e-1, 0.5e-2, 0.5e-3, 0.5e-4, 0.5e-5, 0.5e-6,
0.5e-7, 0.5e-8, 0.5e-9, 0.5e-10,0.5e-11,0.5e-12,0.5e-13,0.5e-14
};
// sign adjustment, instead of testing for fValue<0.0 this will also fetch
// -0.0
bool bSign = rtl::math::isSignBitSet( fValue );
if( bSign )
fValue = -fValue;
if ( rtl::math::isNan( fValue ) )
{
// #i112652# XMLSchema-2
sal_Int32 nCapacity = RTL_CONSTASCII_LENGTH("NaN");
if (pResultCapacity == nullptr)
{
pResultCapacity = &nCapacity;
T::createBuffer(pResult, pResultCapacity);
nResultOffset = 0;
}
T::appendAscii(pResult, pResultCapacity, &nResultOffset,
RTL_CONSTASCII_STRINGPARAM("NaN"));
return;
}
bool bHuge = fValue == HUGE_VAL; // g++ 3.0.1 requires it this way...
if ( bHuge || rtl::math::isInf( fValue ) )
{
// #i112652# XMLSchema-2
sal_Int32 nCapacity = RTL_CONSTASCII_LENGTH("-INF");
if (pResultCapacity == nullptr)
{
pResultCapacity = &nCapacity;
T::createBuffer(pResult, pResultCapacity);
nResultOffset = 0;
}
if ( bSign )
T::appendAscii(pResult, pResultCapacity, &nResultOffset,
RTL_CONSTASCII_STRINGPARAM("-"));
T::appendAscii(pResult, pResultCapacity, &nResultOffset,
RTL_CONSTASCII_STRINGPARAM("INF"));
return;
}
// Use integer representation for integer values that fit into the
// mantissa (1.((2^53)-1)) with a precision of 1 for highest accuracy.
const sal_Int64 kMaxInt = (static_cast<sal_Int64>(1) << 53) - 1;
if ((eFormat == rtl_math_StringFormat_Automatic ||
eFormat == rtl_math_StringFormat_F) && fValue <= static_cast<double>(kMaxInt))
{
sal_Int64 nInt = static_cast<sal_Int64>(fValue);
// Check the integer range again because double comparison may yield
// true within the precision range.
if (nInt <= kMaxInt && static_cast<double>(nInt) == fValue)
{
if (nDecPlaces == rtl_math_DecimalPlaces_Max)
nDecPlaces = 0;
else
nDecPlaces = ::std::max<sal_Int32>( ::std::min<sal_Int32>( nDecPlaces, 15), -15);
if (bEraseTrailingDecZeros && nDecPlaces > 0)
nDecPlaces = 0;
// Round before decimal position.
if (nDecPlaces < 0)
{
sal_Int64 nRounding = static_cast<sal_Int64>( getN10Exp( -nDecPlaces - 1));
sal_Int64 nTemp = nInt / nRounding;
int nDigit = nTemp % 10;
nTemp /= 10;
if (nDigit >= 5)
++nTemp;
nTemp *= 10;
nTemp *= nRounding;
nInt = nTemp;
nDecPlaces = 0;
}
// Max 1 sign, 16 integer digits, 15 group separators, 1 decimal
// separator, 15 decimals digits.
typename T::Char aBuf[64];
typename T::Char * pBuf = aBuf;
typename T::Char * p = pBuf;
// Backward fill.
size_t nGrouping = 0;
sal_Int32 nGroupDigits = 0;
do
{
typename T::Char nDigit = nInt % 10;
nInt /= 10;
*p++ = nDigit + '0';
if (pGroups && pGroups[nGrouping] == ++nGroupDigits && nInt > 0 && cGroupSeparator)
{
*p++ = cGroupSeparator;
if (pGroups[nGrouping+1])
++nGrouping;
nGroupDigits = 0;
}
}
while (nInt > 0);
if (bSign)
*p++ = '-';
// Reverse buffer content.
sal_Int32 n = (p - pBuf) / 2;
for (sal_Int32 i=0; i < n; ++i)
{
::std::swap( pBuf[i], p[-i-1]);
}
// Append decimals.
if (nDecPlaces > 0)
{
*p++ = cDecSeparator;
while (nDecPlaces--)
*p++ = '0';
}
if (pResultCapacity == nullptr)
T::createString(pResult, pBuf, p - pBuf);
else
T::appendChars(pResult, pResultCapacity, &nResultOffset, pBuf, p - pBuf);
return;
}
}
// find the exponent
int nExp = 0;
if ( fValue > 0.0 )
{
nExp = static_cast< int >( floor( log10( fValue ) ) );
fValue /= getN10Exp( nExp );
}
switch ( eFormat )
{
case rtl_math_StringFormat_Automatic :
{ // E or F depending on exponent magnitude
int nPrec;
if ( nExp <= -15 || nExp >= 15 ) // #58531# was <-16, >16
{
nPrec = 14;
eFormat = rtl_math_StringFormat_E;
}
else
{
if ( nExp < 14 )
{
nPrec = 15 - nExp - 1;
eFormat = rtl_math_StringFormat_F;
}
else
{
nPrec = 15;
eFormat = rtl_math_StringFormat_F;
}
}
if ( nDecPlaces == rtl_math_DecimalPlaces_Max )
nDecPlaces = nPrec;
}
break;
case rtl_math_StringFormat_G :
case rtl_math_StringFormat_G1 :
case rtl_math_StringFormat_G2 :
{ // G-Point, similar to sprintf %G
if ( nDecPlaces == rtl_math_DecimalPlaces_DefaultSignificance )
nDecPlaces = 6;
if ( nExp < -4 || nExp >= nDecPlaces )
{
nDecPlaces = std::max< sal_Int32 >( 1, nDecPlaces - 1 );
if( eFormat == rtl_math_StringFormat_G )
eFormat = rtl_math_StringFormat_E;
else if( eFormat == rtl_math_StringFormat_G2 )
eFormat = rtl_math_StringFormat_E2;
else if( eFormat == rtl_math_StringFormat_G1 )
eFormat = rtl_math_StringFormat_E1;
}
else
{
nDecPlaces = std::max< sal_Int32 >( 0, nDecPlaces - nExp - 1 );
eFormat = rtl_math_StringFormat_F;
}
}
break;
default:
break;
}
sal_Int32 nDigits = nDecPlaces + 1;
if( eFormat == rtl_math_StringFormat_F )
nDigits += nExp;
// Round the number
if( nDigits >= 0 )
{
if( ( fValue += nRoundVal[ nDigits > 15 ? 15 : nDigits ] ) >= 10 )
{
fValue = 1.0;
nExp++;
if( eFormat == rtl_math_StringFormat_F )
nDigits++;
}
}
static sal_Int32 const nBufMax = 256;
typename T::Char aBuf[nBufMax];
typename T::Char * pBuf;
sal_Int32 nBuf = static_cast< sal_Int32 >
( nDigits <= 0 ? std::max< sal_Int32 >( nDecPlaces, abs(nExp) )
: nDigits + nDecPlaces ) + 10 + (pGroups ? abs(nDigits) * 2 : 0);
if ( nBuf > nBufMax )
{
pBuf = static_cast< typename T::Char * >(
rtl_allocateMemory(nBuf * sizeof (typename T::Char)));
OSL_ENSURE(pBuf != nullptr, "Out of memory");
}
else
pBuf = aBuf;
typename T::Char * p = pBuf;
if ( bSign )
*p++ = static_cast< typename T::Char >('-');
bool bHasDec = false;
int nDecPos;
// Check for F format and number < 1
if( eFormat == rtl_math_StringFormat_F )
{
if( nExp < 0 )
{
*p++ = static_cast< typename T::Char >('0');
if ( nDecPlaces > 0 )
{
*p++ = cDecSeparator;
bHasDec = true;
}
sal_Int32 i = ( nDigits <= 0 ? nDecPlaces : -nExp - 1 );
while( (i--) > 0 )
*p++ = static_cast< typename T::Char >('0');
nDecPos = 0;
}
else
nDecPos = nExp + 1;
}
else
nDecPos = 1;
int nGrouping = 0, nGroupSelector = 0, nGroupExceed = 0;
if ( nDecPos > 1 && pGroups && pGroups[0] && cGroupSeparator )
{
while ( nGrouping + pGroups[nGroupSelector] < nDecPos )
{
nGrouping += pGroups[ nGroupSelector ];
if ( pGroups[nGroupSelector+1] )
{
if ( nGrouping + pGroups[nGroupSelector+1] >= nDecPos )
break; // while
++nGroupSelector;
}
else if ( !nGroupExceed )
nGroupExceed = nGrouping;
}
}
// print the number
if( nDigits > 0 )
{
for ( int i = 0; ; i++ )
{
if( i < 15 )
{
int nDigit;
if (nDigits-1 == 0 && i > 0 && i < 14)
nDigit = static_cast< int >( floor( fValue
+ nKorrVal[15-i] ) );
else
nDigit = static_cast< int >( fValue + 1E-15 );
if (nDigit >= 10)
{ // after-treatment of up-rounding to the next decade
sal_Int32 sLen = static_cast< long >(p-pBuf)-1;
if (sLen == -1)
{
p = pBuf;
if ( eFormat == rtl_math_StringFormat_F )
{
*p++ = static_cast< typename T::Char >('1');
*p++ = static_cast< typename T::Char >('0');
}
else
{
*p++ = static_cast< typename T::Char >('1');
*p++ = cDecSeparator;
*p++ = static_cast< typename T::Char >('0');
nExp++;
bHasDec = true;
}
}
else
{
for (sal_Int32 j = sLen; j >= 0; j--)
{
typename T::Char cS = pBuf[j];
if (cS != cDecSeparator)
{
if ( cS != static_cast< typename T::Char >('9'))
{
pBuf[j] = ++cS;
j = -1; // break loop
}
else
{
pBuf[j]
= static_cast< typename T::Char >('0');
if (j == 0)
{
if ( eFormat == rtl_math_StringFormat_F)
{ // insert '1'
typename T::Char * px = p++;
while ( pBuf < px )
{
*px = *(px-1);
px--;
}
pBuf[0] = static_cast<
typename T::Char >('1');
}
else
{
pBuf[j] = static_cast<
typename T::Char >('1');
nExp++;
}
}
}
}
}
*p++ = static_cast< typename T::Char >('0');
}
fValue = 0.0;
}
else
{
*p++ = static_cast< typename T::Char >(
nDigit + static_cast< typename T::Char >('0') );
fValue = ( fValue - nDigit ) * 10.0;
}
}
else
*p++ = static_cast< typename T::Char >('0');
if( !--nDigits )
break; // for
if( nDecPos )
{
if( !--nDecPos )
{
*p++ = cDecSeparator;
bHasDec = true;
}
else if ( nDecPos == nGrouping )
{
*p++ = cGroupSeparator;
nGrouping -= pGroups[ nGroupSelector ];
if ( nGroupSelector && nGrouping < nGroupExceed )
--nGroupSelector;
}
}
}
}
if ( !bHasDec && eFormat == rtl_math_StringFormat_F )
{ // nDecPlaces < 0 did round the value
while ( --nDecPos > 0 )
{ // fill before decimal point
if ( nDecPos == nGrouping )
{
*p++ = cGroupSeparator;
nGrouping -= pGroups[ nGroupSelector ];
if ( nGroupSelector && nGrouping < nGroupExceed )
--nGroupSelector;
}
*p++ = static_cast< typename T::Char >('0');
}
}
if ( bEraseTrailingDecZeros && bHasDec && p > pBuf )
{
while ( *(p-1) == static_cast< typename T::Char >('0') )
p--;
if ( *(p-1) == cDecSeparator )
p--;
}
// Print the exponent ('E', followed by '+' or '-', followed by exactly
// three digits for rtl_math_StringFormat_E). The code in
// rtl_[u]str_valueOf{Float|Double} relies on this format.
if( eFormat == rtl_math_StringFormat_E || eFormat == rtl_math_StringFormat_E2 || eFormat == rtl_math_StringFormat_E1 )
{
if ( p == pBuf )
*p++ = static_cast< typename T::Char >('1');
// maybe no nDigits if nDecPlaces < 0
*p++ = static_cast< typename T::Char >('E');
if( nExp < 0 )
{
nExp = -nExp;
*p++ = static_cast< typename T::Char >('-');
}
else
*p++ = static_cast< typename T::Char >('+');
if ( eFormat == rtl_math_StringFormat_E || nExp >= 100 )
*p++ = static_cast< typename T::Char >(
nExp / 100 + static_cast< typename T::Char >('0') );
nExp %= 100;
if ( eFormat == rtl_math_StringFormat_E || eFormat == rtl_math_StringFormat_E2 || nExp >= 10 )
*p++ = static_cast< typename T::Char >(
nExp / 10 + static_cast< typename T::Char >('0') );
*p++ = static_cast< typename T::Char >(
nExp % 10 + static_cast< typename T::Char >('0') );
}
if (pResultCapacity == nullptr)
T::createString(pResult, pBuf, p - pBuf);
else
T::appendChars(pResult, pResultCapacity, &nResultOffset, pBuf,
p - pBuf);
if ( pBuf != &aBuf[0] )
rtl_freeMemory(pBuf);
}
}
void SAL_CALL rtl_math_doubleToString(rtl_String ** pResult,
sal_Int32 * pResultCapacity,
sal_Int32 nResultOffset, double fValue,
rtl_math_StringFormat eFormat,
sal_Int32 nDecPlaces,
sal_Char cDecSeparator,
sal_Int32 const * pGroups,
sal_Char cGroupSeparator,
sal_Bool bEraseTrailingDecZeros)
SAL_THROW_EXTERN_C()
{
doubleToString< StringTraits, StringTraits::String >(
pResult, pResultCapacity, nResultOffset, fValue, eFormat, nDecPlaces,
cDecSeparator, pGroups, cGroupSeparator, bEraseTrailingDecZeros);
}
void SAL_CALL rtl_math_doubleToUString(rtl_uString ** pResult,
sal_Int32 * pResultCapacity,
sal_Int32 nResultOffset, double fValue,
rtl_math_StringFormat eFormat,
sal_Int32 nDecPlaces,
sal_Unicode cDecSeparator,
sal_Int32 const * pGroups,
sal_Unicode cGroupSeparator,
sal_Bool bEraseTrailingDecZeros)
SAL_THROW_EXTERN_C()
{
doubleToString< UStringTraits, UStringTraits::String >(
pResult, pResultCapacity, nResultOffset, fValue, eFormat, nDecPlaces,
cDecSeparator, pGroups, cGroupSeparator, bEraseTrailingDecZeros);
}
namespace {
// if nExp * 10 + nAdd would result in overflow
inline bool long10Overflow( long& nExp, int nAdd )
{
if ( nExp > (LONG_MAX/10)
|| (nExp == (LONG_MAX/10) && nAdd > (LONG_MAX%10)) )
{
nExp = LONG_MAX;
return true;
}
return false;
}
template< typename CharT >
inline double stringToDouble(CharT const * pBegin, CharT const * pEnd,
CharT cDecSeparator, CharT cGroupSeparator,
rtl_math_ConversionStatus * pStatus,
CharT const ** pParsedEnd)
{
double fVal = 0.0;
rtl_math_ConversionStatus eStatus = rtl_math_ConversionStatus_Ok;
CharT const * p0 = pBegin;
while (p0 != pEnd && (*p0 == CharT(' ') || *p0 == CharT('\t')))
++p0;
bool bSign;
if (p0 != pEnd && *p0 == CharT('-'))
{
bSign = true;
++p0;
}
else
{
bSign = false;
if (p0 != pEnd && *p0 == CharT('+'))
++p0;
}
CharT const * p = p0;
bool bDone = false;
// #i112652# XMLSchema-2
if (3 >= (pEnd - p))
{
if ((CharT('N') == p[0]) && (CharT('a') == p[1])
&& (CharT('N') == p[2]))
{
p += 3;
rtl::math::setNan( &fVal );
bDone = true;
}
else if ((CharT('I') == p[0]) && (CharT('N') == p[1])
&& (CharT('F') == p[2]))
{
p += 3;
fVal = HUGE_VAL;
eStatus = rtl_math_ConversionStatus_OutOfRange;
bDone = true;
}
}
if (!bDone) // do not recognize e.g. NaN1.23
{
// leading zeros and group separators may be safely ignored
while (p != pEnd && (*p == CharT('0') || *p == cGroupSeparator))
++p;
long nValExp = 0; // carry along exponent of mantissa
// integer part of mantissa
for (; p != pEnd; ++p)
{
CharT c = *p;
if (rtl::isAsciiDigit(c))
{
fVal = fVal * 10.0 + static_cast< double >( c - CharT('0') );
++nValExp;
}
else if (c != cGroupSeparator)
break;
}
// fraction part of mantissa
if (p != pEnd && *p == cDecSeparator)
{
++p;
double fFrac = 0.0;
long nFracExp = 0;
while (p != pEnd && *p == CharT('0'))
{
--nFracExp;
++p;
}
if ( nValExp == 0 )
nValExp = nFracExp - 1; // no integer part => fraction exponent
// one decimal digit needs ld(10) ~= 3.32 bits
static const int nSigs = (DBL_MANT_DIG / 3) + 1;
int nDigs = 0;
for (; p != pEnd; ++p)
{
CharT c = *p;
if (!rtl::isAsciiDigit(c))
break;
if ( nDigs < nSigs )
{ // further digits (more than nSigs) don't have any
// significance
fFrac = fFrac * 10.0 + static_cast<double>(c - CharT('0'));
--nFracExp;
++nDigs;
}
}
if ( fFrac != 0.0 )
fVal += rtl::math::pow10Exp( fFrac, nFracExp );
else if ( nValExp < 0 )
nValExp = 0; // no digit other than 0 after decimal point
}
if ( nValExp > 0 )
--nValExp; // started with offset +1 at the first mantissa digit
// Exponent
if (p != p0 && p != pEnd && (*p == CharT('E') || *p == CharT('e')))
{
CharT const * const pExponent = p;
++p;
bool bExpSign;
if (p != pEnd && *p == CharT('-'))
{
bExpSign = true;
++p;
}
else
{
bExpSign = false;
if (p != pEnd && *p == CharT('+'))
++p;
}
CharT const * const pFirstExpDigit = p;
if ( fVal == 0.0 )
{ // no matter what follows, zero stays zero, but carry on the
// offset
while (p != pEnd && rtl::isAsciiDigit(*p))
++p;
if (p == pFirstExpDigit)
{ // no digits in exponent, reset end of scan
p = pExponent;
}
}
else
{
bool bOverflow = false;
long nExp = 0;
for (; p != pEnd; ++p)
{
CharT c = *p;
if (!rtl::isAsciiDigit(c))
break;
int i = c - CharT('0');
if ( long10Overflow( nExp, i ) )
bOverflow = true;
else
nExp = nExp * 10 + i;
}
if ( nExp )
{
if ( bExpSign )
nExp = -nExp;
long nAllExp = ( bOverflow ? 0 : nExp + nValExp );
if ( nAllExp > DBL_MAX_10_EXP || (bOverflow && !bExpSign) )
{ // overflow
fVal = HUGE_VAL;
eStatus = rtl_math_ConversionStatus_OutOfRange;
}
else if ((nAllExp < DBL_MIN_10_EXP) ||
(bOverflow && bExpSign) )
{ // underflow
fVal = 0.0;
eStatus = rtl_math_ConversionStatus_OutOfRange;
}
else if ( nExp > DBL_MAX_10_EXP || nExp < DBL_MIN_10_EXP )
{ // compensate exponents
fVal = rtl::math::pow10Exp( fVal, -nValExp );
fVal = rtl::math::pow10Exp( fVal, nAllExp );
}
else
fVal = rtl::math::pow10Exp( fVal, nExp ); // normal
}
else if (p == pFirstExpDigit)
{ // no digits in exponent, reset end of scan
p = pExponent;
}
}
}
else if (p - p0 == 2 && p != pEnd && p[0] == CharT('#')
&& p[-1] == cDecSeparator && p[-2] == CharT('1'))
{
if (pEnd - p >= 4 && p[1] == CharT('I') && p[2] == CharT('N')
&& p[3] == CharT('F'))
{
// "1.#INF", "+1.#INF", "-1.#INF"
p += 4;
fVal = HUGE_VAL;
eStatus = rtl_math_ConversionStatus_OutOfRange;
// Eat any further digits:
while (p != pEnd && rtl::isAsciiDigit(*p))
++p;
}
else if (pEnd - p >= 4 && p[1] == CharT('N') && p[2] == CharT('A')
&& p[3] == CharT('N'))
{
// "1.#NAN", "+1.#NAN", "-1.#NAN"
p += 4;
rtl::math::setNan( &fVal );
if (bSign)
{
union {
double sd;
sal_math_Double md;
} m;
m.sd = fVal;
m.md.w32_parts.msw |= 0x80000000; // create negative NaN
fVal = m.sd;
bSign = false; // don't negate again
}
// Eat any further digits:
while (p != pEnd && rtl::isAsciiDigit(*p))
++p;
}
}
}
// overflow also if more than DBL_MAX_10_EXP digits without decimal
// separator, or 0. and more than DBL_MIN_10_EXP digits, ...
bool bHuge = fVal == HUGE_VAL; // g++ 3.0.1 requires it this way...
if ( bHuge )
eStatus = rtl_math_ConversionStatus_OutOfRange;
if ( bSign )
fVal = -fVal;
if (pStatus != nullptr)
*pStatus = eStatus;
if (pParsedEnd != nullptr)
*pParsedEnd = p == p0 ? pBegin : p;
return fVal;
}
}
double SAL_CALL rtl_math_stringToDouble(sal_Char const * pBegin,
sal_Char const * pEnd,
sal_Char cDecSeparator,
sal_Char cGroupSeparator,
rtl_math_ConversionStatus * pStatus,
sal_Char const ** pParsedEnd)
SAL_THROW_EXTERN_C()
{
return stringToDouble(pBegin, pEnd, cDecSeparator, cGroupSeparator, pStatus,
pParsedEnd);
}
double SAL_CALL rtl_math_uStringToDouble(sal_Unicode const * pBegin,
sal_Unicode const * pEnd,
sal_Unicode cDecSeparator,
sal_Unicode cGroupSeparator,
rtl_math_ConversionStatus * pStatus,
sal_Unicode const ** pParsedEnd)
SAL_THROW_EXTERN_C()
{
return stringToDouble(pBegin, pEnd, cDecSeparator, cGroupSeparator, pStatus,
pParsedEnd);
}
double SAL_CALL rtl_math_round(double fValue, int nDecPlaces,
enum rtl_math_RoundingMode eMode)
SAL_THROW_EXTERN_C()
{
OSL_ASSERT(nDecPlaces >= -20 && nDecPlaces <= 20);
if ( fValue == 0.0 )
return fValue;
// sign adjustment
bool bSign = rtl::math::isSignBitSet( fValue );
if ( bSign )
fValue = -fValue;
double fFac = 0;
if ( nDecPlaces != 0 )
{
// max 20 decimals, we don't have unlimited precision
// #38810# and no overflow on fValue*=fFac
if ( nDecPlaces < -20 || 20 < nDecPlaces || fValue > (DBL_MAX / 1e20) )
return bSign ? -fValue : fValue;
fFac = getN10Exp( nDecPlaces );
fValue *= fFac;
}
//else //! uninitialized fFac, not needed
switch ( eMode )
{
case rtl_math_RoundingMode_Corrected :
{
int nExp; // exponent for correction
if ( fValue > 0.0 )
nExp = static_cast<int>( floor( log10( fValue ) ) );
else
nExp = 0;
int nIndex = 15 - nExp;
if ( nIndex > 15 )
nIndex = 15;
else if ( nIndex <= 1 )
nIndex = 0;
fValue = floor( fValue + 0.5 + nKorrVal[nIndex] );
}
break;
case rtl_math_RoundingMode_Down :
fValue = rtl::math::approxFloor( fValue );
break;
case rtl_math_RoundingMode_Up :
fValue = rtl::math::approxCeil( fValue );
break;
case rtl_math_RoundingMode_Floor :
fValue = bSign ? rtl::math::approxCeil( fValue )
: rtl::math::approxFloor( fValue );
break;
case rtl_math_RoundingMode_Ceiling :
fValue = bSign ? rtl::math::approxFloor( fValue )
: rtl::math::approxCeil( fValue );
break;
case rtl_math_RoundingMode_HalfDown :
{
double f = floor( fValue );
fValue = ((fValue - f) <= 0.5) ? f : ceil( fValue );
}
break;
case rtl_math_RoundingMode_HalfUp :
{
double f = floor( fValue );
fValue = ((fValue - f) < 0.5) ? f : ceil( fValue );
}
break;
case rtl_math_RoundingMode_HalfEven :
#if defined FLT_ROUNDS
/*
Use fast version. FLT_ROUNDS may be defined to a function by some compilers!
DBL_EPSILON is the smallest fractional number which can be represented,
its reciprocal is therefore the smallest number that cannot have a
fractional part. Once you add this reciprocal to `x', its fractional part
is stripped off. Simply subtracting the reciprocal back out returns `x'
without its fractional component.
Simple, clever, and elegant - thanks to Ross Cottrell, the original author,
who placed it into public domain.
volatile: prevent compiler from being too smart
*/
if ( FLT_ROUNDS == 1 )
{
volatile double x = fValue + 1.0 / DBL_EPSILON;
fValue = x - 1.0 / DBL_EPSILON;
}
else
#endif // FLT_ROUNDS
{
double f = floor( fValue );
if ( (fValue - f) != 0.5 )
fValue = floor( fValue + 0.5 );
else
{
double g = f / 2.0;
fValue = (g == floor( g )) ? f : (f + 1.0);
}
}
break;
default:
OSL_ASSERT(false);
break;
}
if ( nDecPlaces != 0 )
fValue /= fFac;
return bSign ? -fValue : fValue;
}
double SAL_CALL rtl_math_pow10Exp(double fValue, int nExp) SAL_THROW_EXTERN_C()
{
return fValue * getN10Exp( nExp );
}
double SAL_CALL rtl_math_approxValue( double fValue ) SAL_THROW_EXTERN_C()
{
if (fValue == 0.0 || fValue == HUGE_VAL || !::rtl::math::isFinite( fValue))
// We don't handle these conditions. Bail out.
return fValue;
double fOrigValue = fValue;
bool bSign = ::rtl::math::isSignBitSet( fValue);
if (bSign)
fValue = -fValue;
int nExp = static_cast<int>( floor( log10( fValue)));
nExp = 14 - nExp;
double fExpValue = getN10Exp( nExp);
fValue *= fExpValue;
// If the original value was near DBL_MIN we got an overflow. Restore and
// bail out.
if (!rtl::math::isFinite( fValue))
return fOrigValue;
fValue = rtl_math_round( fValue, 0, rtl_math_RoundingMode_Corrected);
fValue /= fExpValue;
// If the original value was near DBL_MAX we got an overflow. Restore and
// bail out.
if (!rtl::math::isFinite( fValue))
return fOrigValue;
return bSign ? -fValue : fValue;
}
double SAL_CALL rtl_math_expm1( double fValue ) SAL_THROW_EXTERN_C()
{
return expm1(fValue);
}
double SAL_CALL rtl_math_log1p( double fValue ) SAL_THROW_EXTERN_C()
{
return log1p(fValue);
}
double SAL_CALL rtl_math_atanh( double fValue ) SAL_THROW_EXTERN_C()
{
return 0.5 * rtl_math_log1p( 2.0 * fValue / (1.0-fValue) );
}
/** Parent error function (erf) */
double SAL_CALL rtl_math_erf( double x ) SAL_THROW_EXTERN_C()
{
return erf(x);
}
/** Parent complementary error function (erfc) */
double SAL_CALL rtl_math_erfc( double x ) SAL_THROW_EXTERN_C()
{
return erfc(x);
}
/** improved accuracy of asinh for |x| large and for x near zero
@see #i97605#
*/
double SAL_CALL rtl_math_asinh( double fX ) SAL_THROW_EXTERN_C()
{
if ( fX == 0.0 )
return 0.0;
else
{
double fSign = 1.0;
if ( fX < 0.0 )
{
fX = - fX;
fSign = -1.0;
}
if ( fX < 0.125 )
return fSign * rtl_math_log1p( fX + fX*fX / (1.0 + sqrt( 1.0 + fX*fX)));
else if ( fX < 1.25e7 )
return fSign * log( fX + sqrt( 1.0 + fX*fX));
else
return fSign * log( 2.0*fX);
}
}
/** improved accuracy of acosh for x large and for x near 1
@see #i97605#
*/
double SAL_CALL rtl_math_acosh( double fX ) SAL_THROW_EXTERN_C()
{
volatile double fZ = fX - 1.0;
if ( fX < 1.0 )
{
double fResult;
::rtl::math::setNan( &fResult );
return fResult;
}
else if ( fX == 1.0 )
return 0.0;
else if ( fX < 1.1 )
return rtl_math_log1p( fZ + sqrt( fZ*fZ + 2.0*fZ));
else if ( fX < 1.25e7 )
return log( fX + sqrt( fX*fX - 1.0));
else
return log( 2.0*fX);
}
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */