1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/dom/xslt/base/txDouble.cpp Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,215 @@
1.4 +/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
1.5 +/* This Source Code Form is subject to the terms of the Mozilla Public
1.6 + * License, v. 2.0. If a copy of the MPL was not distributed with this
1.7 + * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
1.8 +
1.9 +#include "mozilla/FloatingPoint.h"
1.10 +
1.11 +#include "nsString.h"
1.12 +#include "txCore.h"
1.13 +#include "txXMLUtils.h"
1.14 +#include <math.h>
1.15 +#include <stdlib.h>
1.16 +#include <algorithm>
1.17 +#ifdef WIN32
1.18 +#include <float.h>
1.19 +#endif
1.20 +#include "prdtoa.h"
1.21 +
1.22 +/*
1.23 + * Utility class for doubles
1.24 + */
1.25 +
1.26 +/*
1.27 + * Converts the given String to a double, if the String value does not
1.28 + * represent a double, NaN will be returned
1.29 + */
1.30 +class txStringToDouble
1.31 +{
1.32 +public:
1.33 + typedef char16_t input_type;
1.34 + typedef char16_t value_type;
1.35 + txStringToDouble(): mState(eWhitestart), mSign(ePositive) {}
1.36 +
1.37 + void
1.38 + write(const input_type* aSource, uint32_t aSourceLength)
1.39 + {
1.40 + if (mState == eIllegal) {
1.41 + return;
1.42 + }
1.43 + uint32_t i = 0;
1.44 + char16_t c;
1.45 + for ( ; i < aSourceLength; ++i) {
1.46 + c = aSource[i];
1.47 + switch (mState) {
1.48 + case eWhitestart:
1.49 + if (c == '-') {
1.50 + mState = eDecimal;
1.51 + mSign = eNegative;
1.52 + }
1.53 + else if (c >= '0' && c <= '9') {
1.54 + mState = eDecimal;
1.55 + mBuffer.Append((char)c);
1.56 + }
1.57 + else if (c == '.') {
1.58 + mState = eMantissa;
1.59 + mBuffer.Append((char)c);
1.60 + }
1.61 + else if (!XMLUtils::isWhitespace(c)) {
1.62 + mState = eIllegal;
1.63 + return;
1.64 + }
1.65 + break;
1.66 + case eDecimal:
1.67 + if (c >= '0' && c <= '9') {
1.68 + mBuffer.Append((char)c);
1.69 + }
1.70 + else if (c == '.') {
1.71 + mState = eMantissa;
1.72 + mBuffer.Append((char)c);
1.73 + }
1.74 + else if (XMLUtils::isWhitespace(c)) {
1.75 + mState = eWhiteend;
1.76 + }
1.77 + else {
1.78 + mState = eIllegal;
1.79 + return;
1.80 + }
1.81 + break;
1.82 + case eMantissa:
1.83 + if (c >= '0' && c <= '9') {
1.84 + mBuffer.Append((char)c);
1.85 + }
1.86 + else if (XMLUtils::isWhitespace(c)) {
1.87 + mState = eWhiteend;
1.88 + }
1.89 + else {
1.90 + mState = eIllegal;
1.91 + return;
1.92 + }
1.93 + break;
1.94 + case eWhiteend:
1.95 + if (!XMLUtils::isWhitespace(c)) {
1.96 + mState = eIllegal;
1.97 + return;
1.98 + }
1.99 + break;
1.100 + default:
1.101 + break;
1.102 + }
1.103 + }
1.104 + }
1.105 +
1.106 + double
1.107 + getDouble()
1.108 + {
1.109 + if (mState == eIllegal || mBuffer.IsEmpty() ||
1.110 + (mBuffer.Length() == 1 && mBuffer[0] == '.')) {
1.111 + return mozilla::UnspecifiedNaN<double>();
1.112 + }
1.113 + return mSign*PR_strtod(mBuffer.get(), 0);
1.114 + }
1.115 +private:
1.116 + nsAutoCString mBuffer;
1.117 + enum {
1.118 + eWhitestart,
1.119 + eDecimal,
1.120 + eMantissa,
1.121 + eWhiteend,
1.122 + eIllegal
1.123 + } mState;
1.124 + enum {
1.125 + eNegative = -1,
1.126 + ePositive = 1
1.127 + } mSign;
1.128 +};
1.129 +
1.130 +double txDouble::toDouble(const nsAString& aSrc)
1.131 +{
1.132 + txStringToDouble sink;
1.133 + nsAString::const_iterator fromBegin, fromEnd;
1.134 + copy_string(aSrc.BeginReading(fromBegin), aSrc.EndReading(fromEnd), sink);
1.135 + return sink.getDouble();
1.136 +}
1.137 +
1.138 +/*
1.139 + * Converts the value of the given double to a String, and places
1.140 + * The result into the destination String.
1.141 + * @return the given dest string
1.142 + */
1.143 +void txDouble::toString(double aValue, nsAString& aDest)
1.144 +{
1.145 +
1.146 + // check for special cases
1.147 +
1.148 + if (mozilla::IsNaN(aValue)) {
1.149 + aDest.AppendLiteral("NaN");
1.150 + return;
1.151 + }
1.152 + if (mozilla::IsInfinite(aValue)) {
1.153 + if (aValue < 0)
1.154 + aDest.Append(char16_t('-'));
1.155 + aDest.AppendLiteral("Infinity");
1.156 + return;
1.157 + }
1.158 +
1.159 + // Mantissa length is 17, so this is plenty
1.160 + const int buflen = 20;
1.161 + char buf[buflen];
1.162 +
1.163 + int intDigits, sign;
1.164 + char* endp;
1.165 + PR_dtoa(aValue, 0, 0, &intDigits, &sign, &endp, buf, buflen - 1);
1.166 +
1.167 + // compute length
1.168 + int32_t length = endp - buf;
1.169 + if (length > intDigits) {
1.170 + // decimal point needed
1.171 + ++length;
1.172 + if (intDigits < 1) {
1.173 + // leading zeros, -intDigits + 1
1.174 + length += 1 - intDigits;
1.175 + }
1.176 + }
1.177 + else {
1.178 + // trailing zeros, total length given by intDigits
1.179 + length = intDigits;
1.180 + }
1.181 + if (aValue < 0)
1.182 + ++length;
1.183 + // grow the string
1.184 + uint32_t oldlength = aDest.Length();
1.185 + if (!aDest.SetLength(oldlength + length, mozilla::fallible_t()))
1.186 + return; // out of memory
1.187 + nsAString::iterator dest;
1.188 + aDest.BeginWriting(dest).advance(int32_t(oldlength));
1.189 + if (aValue < 0) {
1.190 + *dest = '-'; ++dest;
1.191 + }
1.192 + int i;
1.193 + // leading zeros
1.194 + if (intDigits < 1) {
1.195 + *dest = '0'; ++dest;
1.196 + *dest = '.'; ++dest;
1.197 + for (i = 0; i > intDigits; --i) {
1.198 + *dest = '0'; ++dest;
1.199 + }
1.200 + }
1.201 + // mantissa
1.202 + int firstlen = std::min<size_t>(intDigits, endp - buf);
1.203 + for (i = 0; i < firstlen; i++) {
1.204 + *dest = buf[i]; ++dest;
1.205 + }
1.206 + if (i < endp - buf) {
1.207 + if (i > 0) {
1.208 + *dest = '.'; ++dest;
1.209 + }
1.210 + for (; i < endp - buf; i++) {
1.211 + *dest = buf[i]; ++dest;
1.212 + }
1.213 + }
1.214 + // trailing zeros
1.215 + for (; i < intDigits; i++) {
1.216 + *dest = '0'; ++dest;
1.217 + }
1.218 +}
