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// © 2018 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
//
// From the double-conversion library. Original license:
//
// 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.
// ICU PATCH: ifdef around UCONFIG_NO_FORMATTING
#include "unicode/utypes.h"
#if !UCONFIG_NO_FORMATTING
#include <algorithm>
#include <climits>
#include <cmath>
// ICU PATCH: Customize header file paths for ICU.
// The file fixed-dtoa.h is not needed.
#include "double-conversion-double-to-string.h"
#include "double-conversion-bignum-dtoa.h"
#include "double-conversion-fast-dtoa.h"
#include "double-conversion-ieee.h"
#include "double-conversion-utils.h"
// ICU PATCH: Wrap in ICU namespace
U_NAMESPACE_BEGIN
namespace double_conversion {
#if 0 // not needed for ICU
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 {
DOUBLE_CONVERSION_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('+');
}
}
DOUBLE_CONVERSION_ASSERT(exponent < 1e4);
// Changing this constant requires updating the comment of DoubleToStringConverter constructor
const int kMaxExponentLength = 5;
char buffer[kMaxExponentLength + 1];
buffer[kMaxExponentLength] = '\0';
int first_char_pos = kMaxExponentLength;
if (exponent == 0) {
buffer[--first_char_pos] = '0';
} else {
while (exponent > 0) {
buffer[--first_char_pos] = '0' + (exponent % 10);
exponent /= 10;
}
}
// Add prefix '0' to make exponent width >= min(min_exponent_with_, kMaxExponentLength)
// For example: convert 1e+9 -> 1e+09, if min_exponent_with_ is set to 2
while(kMaxExponentLength - first_char_pos < std::min(min_exponent_width_, kMaxExponentLength)) {
buffer[--first_char_pos] = '0';
}
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" or "0.000decimal_rep00".
result_builder->AddCharacter('0');
if (digits_after_point > 0) {
result_builder->AddCharacter('.');
result_builder->AddPadding('0', -decimal_point);
DOUBLE_CONVERSION_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".
DOUBLE_CONVERSION_ASSERT(digits_after_point > 0);
result_builder->AddSubstring(decimal_digits, decimal_point);
result_builder->AddCharacter('.');
DOUBLE_CONVERSION_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 {
DOUBLE_CONVERSION_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,
(std::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 {
DOUBLE_CONVERSION_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;
DOUBLE_CONVERSION_ASSERT(kDecimalRepCapacity > kBase10MaximalLength);
char decimal_rep[kDecimalRepCapacity];
#ifndef NDEBUG
// Problem: there is an assert in StringBuilder::AddSubstring() that
// will pass this buffer to strlen(), and this buffer is not generally
// null-terminated.
memset(decimal_rep, 0, sizeof(decimal_rep));
#endif
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);
DOUBLE_CONVERSION_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);
DOUBLE_CONVERSION_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;
bool as_exponential =
(-decimal_point + 1 > max_leading_padding_zeroes_in_precision_mode_) ||
(decimal_point - precision + extra_zero >
max_trailing_padding_zeroes_in_precision_mode_);
if ((flags_ & NO_TRAILING_ZERO) != 0) {
// Truncate trailing zeros that occur after the decimal point (if exponential,
// that is everything after the first digit).
int stop = as_exponential ? 1 : std::max(1, decimal_point);
while (decimal_rep_length > stop && decimal_rep[decimal_rep_length - 1] == '0') {
--decimal_rep_length;
}
// Clamp precision to avoid the code below re-adding the zeros.
precision = std::min(precision, decimal_rep_length);
}
if (as_exponential) {
// 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,
(std::max)(0, precision - decimal_point),
result_builder);
}
return true;
}
#endif // not needed for ICU
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:
DOUBLE_CONVERSION_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);
DOUBLE_CONVERSION_ASSERT(!Double(v).IsSpecial());
DOUBLE_CONVERSION_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;
#if 0 // not needed for ICU
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;
#endif // not needed for ICU
default:
fast_worked = false;
DOUBLE_CONVERSION_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';
}
} // namespace double_conversion
// ICU PATCH: Close ICU namespace
U_NAMESPACE_END
#endif // ICU PATCH: close #if !UCONFIG_NO_FORMATTING