diff options
Diffstat (limited to 'src/3rdparty/double-conversion/double-conversion.cc')
-rw-r--r-- | src/3rdparty/double-conversion/double-conversion.cc | 975 |
1 files changed, 0 insertions, 975 deletions
diff --git a/src/3rdparty/double-conversion/double-conversion.cc b/src/3rdparty/double-conversion/double-conversion.cc deleted file mode 100644 index 909985be82..0000000000 --- a/src/3rdparty/double-conversion/double-conversion.cc +++ /dev/null @@ -1,975 +0,0 @@ -// Copyright 2010 the V8 project authors. All rights reserved. -// Redistribution and use in source and binary forms, with or without -// modification, are permitted provided that the following conditions are -// met: -// -// * Redistributions of source code must retain the above copyright -// notice, this list of conditions and the following disclaimer. -// * Redistributions in binary form must reproduce the above -// copyright notice, this list of conditions and the following -// disclaimer in the documentation and/or other materials provided -// with the distribution. -// * Neither the name of Google Inc. nor the names of its -// contributors may be used to endorse or promote products derived -// from this software without specific prior written permission. -// -// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS -// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT -// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR -// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT -// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, -// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT -// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, -// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY -// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT -// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE -// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. - -#include <limits.h> -#include <math.h> - -#include "double-conversion.h" - -#include "bignum-dtoa.h" -#include "fast-dtoa.h" -#include "fixed-dtoa.h" -#include "ieee.h" -#include "strtod.h" -#include "utils.h" - -namespace double_conversion { - -const DoubleToStringConverter& DoubleToStringConverter::EcmaScriptConverter() { - int flags = UNIQUE_ZERO | EMIT_POSITIVE_EXPONENT_SIGN; - static DoubleToStringConverter converter(flags, - "Infinity", - "NaN", - 'e', - -6, 21, - 6, 0); - return converter; -} - - -bool DoubleToStringConverter::HandleSpecialValues( - double value, - StringBuilder* result_builder) const { - Double double_inspect(value); - if (double_inspect.IsInfinite()) { - if (infinity_symbol_ == NULL) return false; - if (value < 0) { - result_builder->AddCharacter('-'); - } - result_builder->AddString(infinity_symbol_); - return true; - } - if (double_inspect.IsNan()) { - if (nan_symbol_ == NULL) return false; - result_builder->AddString(nan_symbol_); - return true; - } - return false; -} - - -void DoubleToStringConverter::CreateExponentialRepresentation( - const char* decimal_digits, - int length, - int exponent, - StringBuilder* result_builder) const { - ASSERT(length != 0); - result_builder->AddCharacter(decimal_digits[0]); - if (length != 1) { - result_builder->AddCharacter('.'); - result_builder->AddSubstring(&decimal_digits[1], length-1); - } - result_builder->AddCharacter(exponent_character_); - if (exponent < 0) { - result_builder->AddCharacter('-'); - exponent = -exponent; - } else { - if ((flags_ & EMIT_POSITIVE_EXPONENT_SIGN) != 0) { - result_builder->AddCharacter('+'); - } - } - if (exponent == 0) { - result_builder->AddCharacter('0'); - return; - } - ASSERT(exponent < 1e4); - const int kMaxExponentLength = 5; - char buffer[kMaxExponentLength + 1]; - buffer[kMaxExponentLength] = '\0'; - int first_char_pos = kMaxExponentLength; - while (exponent > 0) { - buffer[--first_char_pos] = '0' + (exponent % 10); - exponent /= 10; - } - result_builder->AddSubstring(&buffer[first_char_pos], - kMaxExponentLength - first_char_pos); -} - - -void DoubleToStringConverter::CreateDecimalRepresentation( - const char* decimal_digits, - int length, - int decimal_point, - int digits_after_point, - StringBuilder* result_builder) const { - // Create a representation that is padded with zeros if needed. - if (decimal_point <= 0) { - // "0.00000decimal_rep". - result_builder->AddCharacter('0'); - if (digits_after_point > 0) { - result_builder->AddCharacter('.'); - result_builder->AddPadding('0', -decimal_point); - ASSERT(length <= digits_after_point - (-decimal_point)); - result_builder->AddSubstring(decimal_digits, length); - int remaining_digits = digits_after_point - (-decimal_point) - length; - result_builder->AddPadding('0', remaining_digits); - } - } else if (decimal_point >= length) { - // "decimal_rep0000.00000" or "decimal_rep.0000" - result_builder->AddSubstring(decimal_digits, length); - result_builder->AddPadding('0', decimal_point - length); - if (digits_after_point > 0) { - result_builder->AddCharacter('.'); - result_builder->AddPadding('0', digits_after_point); - } - } else { - // "decima.l_rep000" - ASSERT(digits_after_point > 0); - result_builder->AddSubstring(decimal_digits, decimal_point); - result_builder->AddCharacter('.'); - ASSERT(length - decimal_point <= digits_after_point); - result_builder->AddSubstring(&decimal_digits[decimal_point], - length - decimal_point); - int remaining_digits = digits_after_point - (length - decimal_point); - result_builder->AddPadding('0', remaining_digits); - } - if (digits_after_point == 0) { - if ((flags_ & EMIT_TRAILING_DECIMAL_POINT) != 0) { - result_builder->AddCharacter('.'); - } - if ((flags_ & EMIT_TRAILING_ZERO_AFTER_POINT) != 0) { - result_builder->AddCharacter('0'); - } - } -} - - -bool DoubleToStringConverter::ToShortestIeeeNumber( - double value, - StringBuilder* result_builder, - DoubleToStringConverter::DtoaMode mode) const { - ASSERT(mode == SHORTEST || mode == SHORTEST_SINGLE); - if (Double(value).IsSpecial()) { - return HandleSpecialValues(value, result_builder); - } - - int decimal_point; - bool sign; - const int kDecimalRepCapacity = kBase10MaximalLength + 1; - char decimal_rep[kDecimalRepCapacity]; - int decimal_rep_length; - - DoubleToAscii(value, mode, 0, decimal_rep, kDecimalRepCapacity, - &sign, &decimal_rep_length, &decimal_point); - - bool unique_zero = (flags_ & UNIQUE_ZERO) != 0; - if (sign && (value != 0.0 || !unique_zero)) { - result_builder->AddCharacter('-'); - } - - int exponent = decimal_point - 1; - if ((decimal_in_shortest_low_ <= exponent) && - (exponent < decimal_in_shortest_high_)) { - CreateDecimalRepresentation(decimal_rep, decimal_rep_length, - decimal_point, - Max(0, decimal_rep_length - decimal_point), - result_builder); - } else { - CreateExponentialRepresentation(decimal_rep, decimal_rep_length, exponent, - result_builder); - } - return true; -} - - -bool DoubleToStringConverter::ToFixed(double value, - int requested_digits, - StringBuilder* result_builder) const { - ASSERT(kMaxFixedDigitsBeforePoint == 60); - const double kFirstNonFixed = 1e60; - - if (Double(value).IsSpecial()) { - return HandleSpecialValues(value, result_builder); - } - - if (requested_digits > kMaxFixedDigitsAfterPoint) return false; - if (value >= kFirstNonFixed || value <= -kFirstNonFixed) return false; - - // Find a sufficiently precise decimal representation of n. - int decimal_point; - bool sign; - // Add space for the '\0' byte. - const int kDecimalRepCapacity = - kMaxFixedDigitsBeforePoint + kMaxFixedDigitsAfterPoint + 1; - char decimal_rep[kDecimalRepCapacity]; - int decimal_rep_length; - DoubleToAscii(value, FIXED, requested_digits, - decimal_rep, kDecimalRepCapacity, - &sign, &decimal_rep_length, &decimal_point); - - bool unique_zero = ((flags_ & UNIQUE_ZERO) != 0); - if (sign && (value != 0.0 || !unique_zero)) { - result_builder->AddCharacter('-'); - } - - CreateDecimalRepresentation(decimal_rep, decimal_rep_length, decimal_point, - requested_digits, result_builder); - return true; -} - - -bool DoubleToStringConverter::ToExponential( - double value, - int requested_digits, - StringBuilder* result_builder) const { - if (Double(value).IsSpecial()) { - return HandleSpecialValues(value, result_builder); - } - - if (requested_digits < -1) return false; - if (requested_digits > kMaxExponentialDigits) return false; - - int decimal_point; - bool sign; - // Add space for digit before the decimal point and the '\0' character. - const int kDecimalRepCapacity = kMaxExponentialDigits + 2; - ASSERT(kDecimalRepCapacity > kBase10MaximalLength); - char decimal_rep[kDecimalRepCapacity]; - int decimal_rep_length; - - if (requested_digits == -1) { - DoubleToAscii(value, SHORTEST, 0, - decimal_rep, kDecimalRepCapacity, - &sign, &decimal_rep_length, &decimal_point); - } else { - DoubleToAscii(value, PRECISION, requested_digits + 1, - decimal_rep, kDecimalRepCapacity, - &sign, &decimal_rep_length, &decimal_point); - ASSERT(decimal_rep_length <= requested_digits + 1); - - for (int i = decimal_rep_length; i < requested_digits + 1; ++i) { - decimal_rep[i] = '0'; - } - decimal_rep_length = requested_digits + 1; - } - - bool unique_zero = ((flags_ & UNIQUE_ZERO) != 0); - if (sign && (value != 0.0 || !unique_zero)) { - result_builder->AddCharacter('-'); - } - - int exponent = decimal_point - 1; - CreateExponentialRepresentation(decimal_rep, - decimal_rep_length, - exponent, - result_builder); - return true; -} - - -bool DoubleToStringConverter::ToPrecision(double value, - int precision, - StringBuilder* result_builder) const { - if (Double(value).IsSpecial()) { - return HandleSpecialValues(value, result_builder); - } - - if (precision < kMinPrecisionDigits || precision > kMaxPrecisionDigits) { - return false; - } - - // Find a sufficiently precise decimal representation of n. - int decimal_point; - bool sign; - // Add one for the terminating null character. - const int kDecimalRepCapacity = kMaxPrecisionDigits + 1; - char decimal_rep[kDecimalRepCapacity]; - int decimal_rep_length; - - DoubleToAscii(value, PRECISION, precision, - decimal_rep, kDecimalRepCapacity, - &sign, &decimal_rep_length, &decimal_point); - ASSERT(decimal_rep_length <= precision); - - bool unique_zero = ((flags_ & UNIQUE_ZERO) != 0); - if (sign && (value != 0.0 || !unique_zero)) { - result_builder->AddCharacter('-'); - } - - // The exponent if we print the number as x.xxeyyy. That is with the - // decimal point after the first digit. - int exponent = decimal_point - 1; - - int extra_zero = ((flags_ & EMIT_TRAILING_ZERO_AFTER_POINT) != 0) ? 1 : 0; - if ((-decimal_point + 1 > max_leading_padding_zeroes_in_precision_mode_) || - (decimal_point - precision + extra_zero > - max_trailing_padding_zeroes_in_precision_mode_)) { - // Fill buffer to contain 'precision' digits. - // Usually the buffer is already at the correct length, but 'DoubleToAscii' - // is allowed to return less characters. - for (int i = decimal_rep_length; i < precision; ++i) { - decimal_rep[i] = '0'; - } - - CreateExponentialRepresentation(decimal_rep, - precision, - exponent, - result_builder); - } else { - CreateDecimalRepresentation(decimal_rep, decimal_rep_length, decimal_point, - Max(0, precision - decimal_point), - result_builder); - } - return true; -} - - -static BignumDtoaMode DtoaToBignumDtoaMode( - DoubleToStringConverter::DtoaMode dtoa_mode) { - switch (dtoa_mode) { - case DoubleToStringConverter::SHORTEST: return BIGNUM_DTOA_SHORTEST; - case DoubleToStringConverter::SHORTEST_SINGLE: - return BIGNUM_DTOA_SHORTEST_SINGLE; - case DoubleToStringConverter::FIXED: return BIGNUM_DTOA_FIXED; - case DoubleToStringConverter::PRECISION: return BIGNUM_DTOA_PRECISION; - default: - UNREACHABLE(); - } -} - - -void DoubleToStringConverter::DoubleToAscii(double v, - DtoaMode mode, - int requested_digits, - char* buffer, - int buffer_length, - bool* sign, - int* length, - int* point) { - Vector<char> vector(buffer, buffer_length); - ASSERT(!Double(v).IsSpecial()); - ASSERT(mode == SHORTEST || mode == SHORTEST_SINGLE || requested_digits >= 0); - - if (Double(v).Sign() < 0) { - *sign = true; - v = -v; - } else { - *sign = false; - } - - if (mode == PRECISION && requested_digits == 0) { - vector[0] = '\0'; - *length = 0; - return; - } - - if (v == 0) { - vector[0] = '0'; - vector[1] = '\0'; - *length = 1; - *point = 1; - return; - } - - bool fast_worked; - switch (mode) { - case SHORTEST: - fast_worked = FastDtoa(v, FAST_DTOA_SHORTEST, 0, vector, length, point); - break; - case SHORTEST_SINGLE: - fast_worked = FastDtoa(v, FAST_DTOA_SHORTEST_SINGLE, 0, - vector, length, point); - break; - case FIXED: - fast_worked = FastFixedDtoa(v, requested_digits, vector, length, point); - break; - case PRECISION: - fast_worked = FastDtoa(v, FAST_DTOA_PRECISION, requested_digits, - vector, length, point); - break; - default: - fast_worked = false; - UNREACHABLE(); - } - if (fast_worked) return; - - // If the fast dtoa didn't succeed use the slower bignum version. - BignumDtoaMode bignum_mode = DtoaToBignumDtoaMode(mode); - BignumDtoa(v, bignum_mode, requested_digits, vector, length, point); - vector[*length] = '\0'; -} - - -// Consumes the given substring from the iterator. -// Returns false, if the substring does not match. -template <class Iterator> -static bool ConsumeSubString(Iterator* current, - Iterator end, - const char* substring) { - ASSERT(**current == *substring); - for (substring++; *substring != '\0'; substring++) { - ++*current; - if (*current == end || **current != *substring) return false; - } - ++*current; - return true; -} - - -// Maximum number of significant digits in decimal representation. -// The longest possible double in decimal representation is -// (2^53 - 1) * 2 ^ -1074 that is (2 ^ 53 - 1) * 5 ^ 1074 / 10 ^ 1074 -// (768 digits). If we parse a number whose first digits are equal to a -// mean of 2 adjacent doubles (that could have up to 769 digits) the result -// must be rounded to the bigger one unless the tail consists of zeros, so -// we don't need to preserve all the digits. -const int kMaxSignificantDigits = 772; - - -static const char kWhitespaceTable7[] = { 32, 13, 10, 9, 11, 12 }; -static const int kWhitespaceTable7Length = ARRAY_SIZE(kWhitespaceTable7); - - -static const uc16 kWhitespaceTable16[] = { - 160, 8232, 8233, 5760, 6158, 8192, 8193, 8194, 8195, - 8196, 8197, 8198, 8199, 8200, 8201, 8202, 8239, 8287, 12288, 65279 -}; -static const int kWhitespaceTable16Length = ARRAY_SIZE(kWhitespaceTable16); - - -static bool isWhitespace(int x) { - if (x < 128) { - for (int i = 0; i < kWhitespaceTable7Length; i++) { - if (kWhitespaceTable7[i] == x) return true; - } - } else { - for (int i = 0; i < kWhitespaceTable16Length; i++) { - if (kWhitespaceTable16[i] == x) return true; - } - } - return false; -} - - -// Returns true if a nonspace found and false if the end has reached. -template <class Iterator> -static inline bool AdvanceToNonspace(Iterator* current, Iterator end) { - while (*current != end) { - if (!isWhitespace(**current)) return true; - ++*current; - } - return false; -} - - -static bool isDigit(int x, int radix) { - return (x >= '0' && x <= '9' && x < '0' + radix) - || (radix > 10 && x >= 'a' && x < 'a' + radix - 10) - || (radix > 10 && x >= 'A' && x < 'A' + radix - 10); -} - - -static double SignedZero(bool sign) { - return sign ? -0.0 : 0.0; -} - - -// Returns true if 'c' is a decimal digit that is valid for the given radix. -// -// The function is small and could be inlined, but VS2012 emitted a warning -// because it constant-propagated the radix and concluded that the last -// condition was always true. By moving it into a separate function the -// compiler wouldn't warn anymore. -static bool IsDecimalDigitForRadix(int c, int radix) { - return '0' <= c && c <= '9' && (c - '0') < radix; -} - -// Returns true if 'c' is a character digit that is valid for the given radix. -// The 'a_character' should be 'a' or 'A'. -// -// The function is small and could be inlined, but VS2012 emitted a warning -// because it constant-propagated the radix and concluded that the first -// condition was always false. By moving it into a separate function the -// compiler wouldn't warn anymore. -static bool IsCharacterDigitForRadix(int c, int radix, char a_character) { - return radix > 10 && c >= a_character && c < a_character + radix - 10; -} - - -// Parsing integers with radix 2, 4, 8, 16, 32. Assumes current != end. -template <int radix_log_2, class Iterator> -static double RadixStringToIeee(Iterator* current, - Iterator end, - bool sign, - bool allow_trailing_junk, - double junk_string_value, - bool read_as_double, - bool* result_is_junk) { - ASSERT(*current != end); - - const int kDoubleSize = Double::kSignificandSize; - const int kSingleSize = Single::kSignificandSize; - const int kSignificandSize = read_as_double? kDoubleSize: kSingleSize; - - *result_is_junk = true; - - // Skip leading 0s. - while (**current == '0') { - ++(*current); - if (*current == end) { - *result_is_junk = false; - return SignedZero(sign); - } - } - - int64_t number = 0; - int exponent = 0; - const int radix = (1 << radix_log_2); - - do { - int digit; - if (IsDecimalDigitForRadix(**current, radix)) { - digit = static_cast<char>(**current) - '0'; - } else if (IsCharacterDigitForRadix(**current, radix, 'a')) { - digit = static_cast<char>(**current) - 'a' + 10; - } else if (IsCharacterDigitForRadix(**current, radix, 'A')) { - digit = static_cast<char>(**current) - 'A' + 10; - } else { - if (allow_trailing_junk || !AdvanceToNonspace(current, end)) { - break; - } else { - return junk_string_value; - } - } - - number = number * radix + digit; - int overflow = static_cast<int>(number >> kSignificandSize); - if (overflow != 0) { - // Overflow occurred. Need to determine which direction to round the - // result. - int overflow_bits_count = 1; - while (overflow > 1) { - overflow_bits_count++; - overflow >>= 1; - } - - int dropped_bits_mask = ((1 << overflow_bits_count) - 1); - int dropped_bits = static_cast<int>(number) & dropped_bits_mask; - number >>= overflow_bits_count; - exponent = overflow_bits_count; - - bool zero_tail = true; - for (;;) { - ++(*current); - if (*current == end || !isDigit(**current, radix)) break; - zero_tail = zero_tail && **current == '0'; - exponent += radix_log_2; - } - - if (!allow_trailing_junk && AdvanceToNonspace(current, end)) { - return junk_string_value; - } - - int middle_value = (1 << (overflow_bits_count - 1)); - if (dropped_bits > middle_value) { - number++; // Rounding up. - } else if (dropped_bits == middle_value) { - // Rounding to even to consistency with decimals: half-way case rounds - // up if significant part is odd and down otherwise. - if ((number & 1) != 0 || !zero_tail) { - number++; // Rounding up. - } - } - - // Rounding up may cause overflow. - if ((number & ((int64_t)1 << kSignificandSize)) != 0) { - exponent++; - number >>= 1; - } - break; - } - ++(*current); - } while (*current != end); - - ASSERT(number < ((int64_t)1 << kSignificandSize)); - ASSERT(static_cast<int64_t>(static_cast<double>(number)) == number); - - *result_is_junk = false; - - if (exponent == 0) { - if (sign) { - if (number == 0) return -0.0; - number = -number; - } - return static_cast<double>(number); - } - - ASSERT(number != 0); - return Double(DiyFp(number, exponent)).value(); -} - - -template <class Iterator> -double StringToDoubleConverter::StringToIeee( - Iterator input, - int length, - bool read_as_double, - int* processed_characters_count) const { - Iterator current = input; - Iterator end = input + length; - - *processed_characters_count = 0; - - const bool allow_trailing_junk = (flags_ & ALLOW_TRAILING_JUNK) != 0; - const bool allow_leading_spaces = (flags_ & ALLOW_LEADING_SPACES) != 0; - const bool allow_trailing_spaces = (flags_ & ALLOW_TRAILING_SPACES) != 0; - const bool allow_spaces_after_sign = (flags_ & ALLOW_SPACES_AFTER_SIGN) != 0; - - // To make sure that iterator dereferencing is valid the following - // convention is used: - // 1. Each '++current' statement is followed by check for equality to 'end'. - // 2. If AdvanceToNonspace returned false then current == end. - // 3. If 'current' becomes equal to 'end' the function returns or goes to - // 'parsing_done'. - // 4. 'current' is not dereferenced after the 'parsing_done' label. - // 5. Code before 'parsing_done' may rely on 'current != end'. - if (current == end) return empty_string_value_; - - if (allow_leading_spaces || allow_trailing_spaces) { - if (!AdvanceToNonspace(¤t, end)) { - *processed_characters_count = static_cast<int>(current - input); - return empty_string_value_; - } - if (!allow_leading_spaces && (input != current)) { - // No leading spaces allowed, but AdvanceToNonspace moved forward. - return junk_string_value_; - } - } - - // The longest form of simplified number is: "-<significant digits>.1eXXX\0". - const int kBufferSize = kMaxSignificantDigits + 10; - char buffer[kBufferSize]; // NOLINT: size is known at compile time. - int buffer_pos = 0; - - // Exponent will be adjusted if insignificant digits of the integer part - // or insignificant leading zeros of the fractional part are dropped. - int exponent = 0; - int significant_digits = 0; - int insignificant_digits = 0; - bool nonzero_digit_dropped = false; - - bool sign = false; - - if (*current == '+' || *current == '-') { - sign = (*current == '-'); - ++current; - Iterator next_non_space = current; - // Skip following spaces (if allowed). - if (!AdvanceToNonspace(&next_non_space, end)) return junk_string_value_; - if (!allow_spaces_after_sign && (current != next_non_space)) { - return junk_string_value_; - } - current = next_non_space; - } - - if (infinity_symbol_ != NULL) { - if (*current == infinity_symbol_[0]) { - if (!ConsumeSubString(¤t, end, infinity_symbol_)) { - return junk_string_value_; - } - - if (!(allow_trailing_spaces || allow_trailing_junk) && (current != end)) { - return junk_string_value_; - } - if (!allow_trailing_junk && AdvanceToNonspace(¤t, end)) { - return junk_string_value_; - } - - ASSERT(buffer_pos == 0); - *processed_characters_count = static_cast<int>(current - input); - return sign ? -Double::Infinity() : Double::Infinity(); - } - } - - if (nan_symbol_ != NULL) { - if (*current == nan_symbol_[0]) { - if (!ConsumeSubString(¤t, end, nan_symbol_)) { - return junk_string_value_; - } - - if (!(allow_trailing_spaces || allow_trailing_junk) && (current != end)) { - return junk_string_value_; - } - if (!allow_trailing_junk && AdvanceToNonspace(¤t, end)) { - return junk_string_value_; - } - - ASSERT(buffer_pos == 0); - *processed_characters_count = static_cast<int>(current - input); - return sign ? -Double::NaN() : Double::NaN(); - } - } - - bool leading_zero = false; - if (*current == '0') { - ++current; - if (current == end) { - *processed_characters_count = static_cast<int>(current - input); - return SignedZero(sign); - } - - leading_zero = true; - - // It could be hexadecimal value. - if ((flags_ & ALLOW_HEX) && (*current == 'x' || *current == 'X')) { - ++current; - if (current == end || !isDigit(*current, 16)) { - return junk_string_value_; // "0x". - } - - bool result_is_junk; - double result = RadixStringToIeee<4>(¤t, - end, - sign, - allow_trailing_junk, - junk_string_value_, - read_as_double, - &result_is_junk); - if (!result_is_junk) { - if (allow_trailing_spaces) AdvanceToNonspace(¤t, end); - *processed_characters_count = static_cast<int>(current - input); - } - return result; - } - - // Ignore leading zeros in the integer part. - while (*current == '0') { - ++current; - if (current == end) { - *processed_characters_count = static_cast<int>(current - input); - return SignedZero(sign); - } - } - } - - bool octal = leading_zero && (flags_ & ALLOW_OCTALS) != 0; - - // Copy significant digits of the integer part (if any) to the buffer. - while (*current >= '0' && *current <= '9') { - if (significant_digits < kMaxSignificantDigits) { - ASSERT(buffer_pos < kBufferSize); - buffer[buffer_pos++] = static_cast<char>(*current); - significant_digits++; - // Will later check if it's an octal in the buffer. - } else { - insignificant_digits++; // Move the digit into the exponential part. - nonzero_digit_dropped = nonzero_digit_dropped || *current != '0'; - } - octal = octal && *current < '8'; - ++current; - if (current == end) goto parsing_done; - } - - if (significant_digits == 0) { - octal = false; - } - - if (*current == '.') { - if (octal && !allow_trailing_junk) return junk_string_value_; - if (octal) goto parsing_done; - - ++current; - if (current == end) { - if (significant_digits == 0 && !leading_zero) { - return junk_string_value_; - } else { - goto parsing_done; - } - } - - if (significant_digits == 0) { - // octal = false; - // Integer part consists of 0 or is absent. Significant digits start after - // leading zeros (if any). - while (*current == '0') { - ++current; - if (current == end) { - *processed_characters_count = static_cast<int>(current - input); - return SignedZero(sign); - } - exponent--; // Move this 0 into the exponent. - } - } - - // There is a fractional part. - // We don't emit a '.', but adjust the exponent instead. - while (*current >= '0' && *current <= '9') { - if (significant_digits < kMaxSignificantDigits) { - ASSERT(buffer_pos < kBufferSize); - buffer[buffer_pos++] = static_cast<char>(*current); - significant_digits++; - exponent--; - } else { - // Ignore insignificant digits in the fractional part. - nonzero_digit_dropped = nonzero_digit_dropped || *current != '0'; - } - ++current; - if (current == end) goto parsing_done; - } - } - - if (!leading_zero && exponent == 0 && significant_digits == 0) { - // If leading_zeros is true then the string contains zeros. - // If exponent < 0 then string was [+-]\.0*... - // If significant_digits != 0 the string is not equal to 0. - // Otherwise there are no digits in the string. - return junk_string_value_; - } - - // Parse exponential part. - if (*current == 'e' || *current == 'E') { - if (octal && !allow_trailing_junk) return junk_string_value_; - if (octal) goto parsing_done; - ++current; - if (current == end) { - if (allow_trailing_junk) { - goto parsing_done; - } else { - return junk_string_value_; - } - } - char sign = '+'; - if (*current == '+' || *current == '-') { - sign = static_cast<char>(*current); - ++current; - if (current == end) { - if (allow_trailing_junk) { - goto parsing_done; - } else { - return junk_string_value_; - } - } - } - - if (current == end || *current < '0' || *current > '9') { - if (allow_trailing_junk) { - goto parsing_done; - } else { - return junk_string_value_; - } - } - - const int max_exponent = INT_MAX / 2; - ASSERT(-max_exponent / 2 <= exponent && exponent <= max_exponent / 2); - int num = 0; - do { - // Check overflow. - int digit = *current - '0'; - if (num >= max_exponent / 10 - && !(num == max_exponent / 10 && digit <= max_exponent % 10)) { - num = max_exponent; - } else { - num = num * 10 + digit; - } - ++current; - } while (current != end && *current >= '0' && *current <= '9'); - - exponent += (sign == '-' ? -num : num); - } - - if (!(allow_trailing_spaces || allow_trailing_junk) && (current != end)) { - return junk_string_value_; - } - if (!allow_trailing_junk && AdvanceToNonspace(¤t, end)) { - return junk_string_value_; - } - if (allow_trailing_spaces) { - AdvanceToNonspace(¤t, end); - } - - parsing_done: - exponent += insignificant_digits; - - if (octal) { - double result; - bool result_is_junk; - char* start = buffer; - result = RadixStringToIeee<3>(&start, - buffer + buffer_pos, - sign, - allow_trailing_junk, - junk_string_value_, - read_as_double, - &result_is_junk); - ASSERT(!result_is_junk); - *processed_characters_count = static_cast<int>(current - input); - return result; - } - - if (nonzero_digit_dropped) { - buffer[buffer_pos++] = '1'; - exponent--; - } - - ASSERT(buffer_pos < kBufferSize); - buffer[buffer_pos] = '\0'; - - double converted; - if (read_as_double) { - converted = Strtod(Vector<const char>(buffer, buffer_pos), exponent); - } else { - converted = Strtof(Vector<const char>(buffer, buffer_pos), exponent); - } - *processed_characters_count = static_cast<int>(current - input); - return sign? -converted: converted; -} - - -double StringToDoubleConverter::StringToDouble( - const char* buffer, - int length, - int* processed_characters_count) const { - return StringToIeee(buffer, length, true, processed_characters_count); -} - - -double StringToDoubleConverter::StringToDouble( - const uc16* buffer, - int length, - int* processed_characters_count) const { - return StringToIeee(buffer, length, true, processed_characters_count); -} - - -float StringToDoubleConverter::StringToFloat( - const char* buffer, - int length, - int* processed_characters_count) const { - return static_cast<float>(StringToIeee(buffer, length, false, - processed_characters_count)); -} - - -float StringToDoubleConverter::StringToFloat( - const uc16* buffer, - int length, - int* processed_characters_count) const { - return static_cast<float>(StringToIeee(buffer, length, false, - processed_characters_count)); -} - -} // namespace double_conversion |