| /* |
| * Copyright (C) 2002, 2003 The Karbon Developers |
| * Copyright (C) 2006 Alexander Kellett <lypanov@kde.org> |
| * Copyright (C) 2006, 2007 Rob Buis <buis@kde.org> |
| * Copyright (C) 2007, 2009, 2013 Apple Inc. All rights reserved. |
| * |
| * This library is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Library General Public |
| * License as published by the Free Software Foundation; either |
| * version 2 of the License, or (at your option) any later version. |
| * |
| * This library is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Library General Public License for more details. |
| * |
| * You should have received a copy of the GNU Library General Public License |
| * along with this library; see the file COPYING.LIB. If not, write to |
| * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, |
| * Boston, MA 02110-1301, USA. |
| */ |
| |
| #include "core/svg/SVGParserUtilities.h" |
| |
| #include "wtf/MathExtras.h" |
| #include <limits> |
| |
| namespace blink { |
| |
| template <typename FloatType> |
| static inline bool isValidRange(const FloatType& x) |
| { |
| static const FloatType max = std::numeric_limits<FloatType>::max(); |
| return x >= -max && x <= max; |
| } |
| |
| // We use this generic parseNumber function to allow the Path parsing code to work |
| // at a higher precision internally, without any unnecessary runtime cost or code |
| // complexity. |
| template <typename CharType, typename FloatType> |
| static bool genericParseNumber(const CharType*& cursor, const CharType* end, FloatType& number, WhitespaceMode mode) |
| { |
| FloatType integer, decimal, frac, exponent; |
| int sign, expsign; |
| |
| exponent = 0; |
| integer = 0; |
| frac = 1; |
| decimal = 0; |
| sign = 1; |
| expsign = 1; |
| |
| if (mode & AllowLeadingWhitespace) |
| skipOptionalSVGSpaces(cursor, end); |
| |
| const CharType* ptr = cursor; |
| // read the sign |
| if (ptr < end && *ptr == '+') |
| ptr++; |
| else if (ptr < end && *ptr == '-') { |
| ptr++; |
| sign = -1; |
| } |
| |
| if (ptr == end || ((*ptr < '0' || *ptr > '9') && *ptr != '.')) |
| // The first character of a number must be one of [0-9+-.] |
| return false; |
| |
| // read the integer part, build right-to-left |
| const CharType* digitsStart = ptr; |
| while (ptr < end && *ptr >= '0' && *ptr <= '9') |
| ++ptr; // Advance to first non-digit. |
| |
| if (ptr != digitsStart) { |
| const CharType* ptrScanIntPart = ptr - 1; |
| FloatType multiplier = 1; |
| while (ptrScanIntPart >= digitsStart) { |
| integer += multiplier * static_cast<FloatType>(*(ptrScanIntPart--) - '0'); |
| multiplier *= 10; |
| } |
| // Bail out early if this overflows. |
| if (!isValidRange(integer)) |
| return false; |
| } |
| |
| if (ptr < end && *ptr == '.') { // read the decimals |
| ptr++; |
| |
| // There must be a least one digit following the . |
| if (ptr >= end || *ptr < '0' || *ptr > '9') |
| return false; |
| |
| while (ptr < end && *ptr >= '0' && *ptr <= '9') |
| decimal += (*(ptr++) - '0') * (frac *= static_cast<FloatType>(0.1)); |
| } |
| |
| // When we get here we should have consumed either a digit for the integer |
| // part or a fractional part (with at least one digit after the '.'.) |
| ASSERT(digitsStart != ptr); |
| |
| // read the exponent part |
| if (ptr + 1 < end && (*ptr == 'e' || *ptr == 'E') |
| && (ptr[1] != 'x' && ptr[1] != 'm')) { |
| ptr++; |
| |
| // read the sign of the exponent |
| if (*ptr == '+') |
| ptr++; |
| else if (*ptr == '-') { |
| ptr++; |
| expsign = -1; |
| } |
| |
| // There must be an exponent |
| if (ptr >= end || *ptr < '0' || *ptr > '9') |
| return false; |
| |
| while (ptr < end && *ptr >= '0' && *ptr <= '9') { |
| exponent *= static_cast<FloatType>(10); |
| exponent += *ptr - '0'; |
| ptr++; |
| } |
| // Make sure exponent is valid. |
| if (!isValidRange(exponent) || exponent > std::numeric_limits<FloatType>::max_exponent) |
| return false; |
| } |
| |
| number = integer + decimal; |
| number *= sign; |
| |
| if (exponent) |
| number *= static_cast<FloatType>(pow(10.0, expsign * static_cast<int>(exponent))); |
| |
| // Don't return Infinity() or NaN(). |
| if (!isValidRange(number)) |
| return false; |
| |
| // A valid number has been parsed. Commit cursor. |
| cursor = ptr; |
| |
| if (mode & AllowTrailingWhitespace) |
| skipOptionalSVGSpacesOrDelimiter(cursor, end); |
| |
| return true; |
| } |
| |
| bool parseNumber(const LChar*& ptr, const LChar* end, float& number, WhitespaceMode mode) |
| { |
| return genericParseNumber(ptr, end, number, mode); |
| } |
| |
| bool parseNumber(const UChar*& ptr, const UChar* end, float& number, WhitespaceMode mode) |
| { |
| return genericParseNumber(ptr, end, number, mode); |
| } |
| |
| // only used to parse largeArcFlag and sweepFlag which must be a "0" or "1" |
| // and might not have any whitespace/comma after it |
| template <typename CharType> |
| bool genericParseArcFlag(const CharType*& ptr, const CharType* end, bool& flag) |
| { |
| if (ptr >= end) |
| return false; |
| const CharType flagChar = *ptr; |
| if (flagChar == '0') |
| flag = false; |
| else if (flagChar == '1') |
| flag = true; |
| else |
| return false; |
| |
| ptr++; |
| skipOptionalSVGSpacesOrDelimiter(ptr, end); |
| |
| return true; |
| } |
| |
| bool parseArcFlag(const LChar*& ptr, const LChar* end, bool& flag) |
| { |
| return genericParseArcFlag(ptr, end, flag); |
| } |
| |
| bool parseArcFlag(const UChar*& ptr, const UChar* end, bool& flag) |
| { |
| return genericParseArcFlag(ptr, end, flag); |
| } |
| |
| template<typename CharType> |
| static bool genericParseNumberOptionalNumber(const CharType*& ptr, const CharType* end, float& x, float& y) |
| { |
| if (!parseNumber(ptr, end, x)) |
| return false; |
| |
| if (ptr == end) |
| y = x; |
| else if (!parseNumber(ptr, end, y, AllowLeadingAndTrailingWhitespace)) |
| return false; |
| |
| return ptr == end; |
| } |
| |
| bool parseNumberOptionalNumber(const String& string, float& x, float& y) |
| { |
| if (string.isEmpty()) |
| return false; |
| |
| if (string.is8Bit()) { |
| const LChar* ptr = string.characters8(); |
| const LChar* end = ptr + string.length(); |
| return genericParseNumberOptionalNumber(ptr, end, x, y); |
| } |
| const UChar* ptr = string.characters16(); |
| const UChar* end = ptr + string.length(); |
| return genericParseNumberOptionalNumber(ptr, end, x, y); |
| } |
| |
| } // namespace blink |