michael@0: /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #include "mozilla/FloatingPoint.h"
michael@0: 
michael@0: #include "nsString.h"
michael@0: #include "txCore.h"
michael@0: #include "txXMLUtils.h"
michael@0: #include <math.h>
michael@0: #include <stdlib.h>
michael@0: #include <algorithm>
michael@0: #ifdef WIN32
michael@0: #include <float.h>
michael@0: #endif
michael@0: #include "prdtoa.h"
michael@0: 
michael@0: /*
michael@0:  * Utility class for doubles
michael@0:  */
michael@0: 
michael@0: /*
michael@0:  * Converts the given String to a double, if the String value does not
michael@0:  * represent a double, NaN will be returned
michael@0:  */
michael@0: class txStringToDouble
michael@0: {
michael@0: public:
michael@0:     typedef char16_t input_type;
michael@0:     typedef char16_t value_type;
michael@0:     txStringToDouble(): mState(eWhitestart), mSign(ePositive) {}
michael@0: 
michael@0:     void
michael@0:     write(const input_type* aSource, uint32_t aSourceLength)
michael@0:     {
michael@0:         if (mState == eIllegal) {
michael@0:             return;
michael@0:         }
michael@0:         uint32_t i = 0;
michael@0:         char16_t c;
michael@0:         for ( ; i < aSourceLength; ++i) {
michael@0:             c = aSource[i];
michael@0:             switch (mState) {
michael@0:                 case eWhitestart:
michael@0:                     if (c == '-') {
michael@0:                         mState = eDecimal;
michael@0:                         mSign = eNegative;
michael@0:                     }
michael@0:                     else if (c >= '0' && c <= '9') {
michael@0:                         mState = eDecimal;
michael@0:                         mBuffer.Append((char)c);
michael@0:                     }
michael@0:                     else if (c == '.') {
michael@0:                         mState = eMantissa;
michael@0:                         mBuffer.Append((char)c);
michael@0:                     }
michael@0:                     else if (!XMLUtils::isWhitespace(c)) {
michael@0:                         mState = eIllegal;
michael@0:                         return;
michael@0:                     }
michael@0:                     break;
michael@0:                 case eDecimal:
michael@0:                     if (c >= '0' && c <= '9') {
michael@0:                         mBuffer.Append((char)c);
michael@0:                     }
michael@0:                     else if (c == '.') {
michael@0:                         mState = eMantissa;
michael@0:                         mBuffer.Append((char)c);
michael@0:                     }
michael@0:                     else if (XMLUtils::isWhitespace(c)) {
michael@0:                         mState = eWhiteend;
michael@0:                     }
michael@0:                     else {
michael@0:                         mState = eIllegal;
michael@0:                         return;
michael@0:                     }
michael@0:                     break;
michael@0:                 case eMantissa:
michael@0:                     if (c >= '0' && c <= '9') {
michael@0:                         mBuffer.Append((char)c);
michael@0:                     }
michael@0:                     else if (XMLUtils::isWhitespace(c)) {
michael@0:                         mState = eWhiteend;
michael@0:                     }
michael@0:                     else {
michael@0:                         mState = eIllegal;
michael@0:                         return;
michael@0:                     }
michael@0:                     break;
michael@0:                 case eWhiteend:
michael@0:                     if (!XMLUtils::isWhitespace(c)) {
michael@0:                         mState = eIllegal;
michael@0:                         return;
michael@0:                     }
michael@0:                     break;
michael@0:                 default:
michael@0:                     break;
michael@0:             }
michael@0:         }
michael@0:     }
michael@0: 
michael@0:     double
michael@0:     getDouble()
michael@0:     {
michael@0:         if (mState == eIllegal || mBuffer.IsEmpty() ||
michael@0:             (mBuffer.Length() == 1 && mBuffer[0] == '.')) {
michael@0:             return mozilla::UnspecifiedNaN<double>();
michael@0:         }
michael@0:         return mSign*PR_strtod(mBuffer.get(), 0);
michael@0:     }
michael@0: private:
michael@0:     nsAutoCString mBuffer;
michael@0:     enum {
michael@0:         eWhitestart,
michael@0:         eDecimal,
michael@0:         eMantissa,
michael@0:         eWhiteend,
michael@0:         eIllegal
michael@0:     } mState;
michael@0:     enum {
michael@0:         eNegative = -1,
michael@0:         ePositive = 1
michael@0:     } mSign;
michael@0: };
michael@0: 
michael@0: double txDouble::toDouble(const nsAString& aSrc)
michael@0: {
michael@0:     txStringToDouble sink;
michael@0:     nsAString::const_iterator fromBegin, fromEnd;
michael@0:     copy_string(aSrc.BeginReading(fromBegin), aSrc.EndReading(fromEnd), sink);
michael@0:     return sink.getDouble();
michael@0: }
michael@0: 
michael@0: /*
michael@0:  * Converts the value of the given double to a String, and places
michael@0:  * The result into the destination String.
michael@0:  * @return the given dest string
michael@0:  */
michael@0: void txDouble::toString(double aValue, nsAString& aDest)
michael@0: {
michael@0: 
michael@0:     // check for special cases
michael@0: 
michael@0:     if (mozilla::IsNaN(aValue)) {
michael@0:         aDest.AppendLiteral("NaN");
michael@0:         return;
michael@0:     }
michael@0:     if (mozilla::IsInfinite(aValue)) {
michael@0:         if (aValue < 0)
michael@0:             aDest.Append(char16_t('-'));
michael@0:         aDest.AppendLiteral("Infinity");
michael@0:         return;
michael@0:     }
michael@0: 
michael@0:     // Mantissa length is 17, so this is plenty
michael@0:     const int buflen = 20;
michael@0:     char buf[buflen];
michael@0: 
michael@0:     int intDigits, sign;
michael@0:     char* endp;
michael@0:     PR_dtoa(aValue, 0, 0, &intDigits, &sign, &endp, buf, buflen - 1);
michael@0: 
michael@0:     // compute length
michael@0:     int32_t length = endp - buf;
michael@0:     if (length > intDigits) {
michael@0:         // decimal point needed
michael@0:         ++length;
michael@0:         if (intDigits < 1) {
michael@0:             // leading zeros, -intDigits + 1
michael@0:             length += 1 - intDigits;
michael@0:         }
michael@0:     }
michael@0:     else {
michael@0:         // trailing zeros, total length given by intDigits
michael@0:         length = intDigits;
michael@0:     }
michael@0:     if (aValue < 0)
michael@0:         ++length;
michael@0:     // grow the string
michael@0:     uint32_t oldlength = aDest.Length();
michael@0:     if (!aDest.SetLength(oldlength + length, mozilla::fallible_t()))
michael@0:         return; // out of memory
michael@0:     nsAString::iterator dest;
michael@0:     aDest.BeginWriting(dest).advance(int32_t(oldlength));
michael@0:     if (aValue < 0) {
michael@0:         *dest = '-'; ++dest;
michael@0:     }
michael@0:     int i;
michael@0:     // leading zeros
michael@0:     if (intDigits < 1) {
michael@0:         *dest = '0'; ++dest;
michael@0:         *dest = '.'; ++dest;
michael@0:         for (i = 0; i > intDigits; --i) {
michael@0:             *dest = '0'; ++dest;
michael@0:         }
michael@0:     }
michael@0:     // mantissa
michael@0:     int firstlen = std::min<size_t>(intDigits, endp - buf);
michael@0:     for (i = 0; i < firstlen; i++) {
michael@0:         *dest = buf[i]; ++dest;
michael@0:     }
michael@0:     if (i < endp - buf) {
michael@0:         if (i > 0) {
michael@0:             *dest = '.'; ++dest;
michael@0:         }
michael@0:         for (; i < endp - buf; i++) {
michael@0:             *dest = buf[i]; ++dest;
michael@0:         }
michael@0:     }
michael@0:     // trailing zeros
michael@0:     for (; i < intDigits; i++) {
michael@0:         *dest = '0'; ++dest;
michael@0:     }
michael@0: }