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Format.cpp
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/*
* Copyright (c) 2020, the SerenityOS developers.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/CharacterTypes.h>
#include <AK/Format.h>
#include <AK/GenericLexer.h>
#include <AK/IntegralMath.h>
#include <AK/LexicalPath.h>
#include <AK/String.h>
#include <AK/StringBuilder.h>
#include <AK/StringFloatingPointConversions.h>
#include <math.h>
#include <stdio.h>
#include <string.h>
#include <time.h>
#if defined(AK_OS_SERENITY)
# include <serenity.h>
#endif
#if defined(AK_OS_ANDROID)
# include <android/log.h>
#endif
#if defined(AK_OS_WINDOWS)
# include <AK/Windows.h>
#endif
namespace AK {
class FormatParser : public GenericLexer {
public:
struct FormatSpecifier {
StringView flags;
size_t index;
};
explicit FormatParser(StringView input);
StringView consume_literal();
bool consume_number(size_t& value);
bool consume_specifier(FormatSpecifier& specifier);
bool consume_replacement_field(size_t& index);
};
namespace {
static constexpr size_t use_next_index = NumericLimits<size_t>::max();
// The worst case is that we have the largest 64-bit value formatted as binary number, this would take
// 65 bytes (85 bytes with separators). Choosing a larger power of two won't hurt and is a bit of mitigation against out-of-bounds accesses.
static constexpr size_t convert_unsigned_to_string(u64 value, Array<u8, 128>& buffer, u8 base, bool upper_case, bool use_separator)
{
VERIFY(base >= 2 && base <= 16);
constexpr char const* lowercase_lookup = "0123456789abcdef";
constexpr char const* uppercase_lookup = "0123456789ABCDEF";
if (value == 0) {
buffer[0] = '0';
return 1;
}
size_t used = 0;
size_t digit_count = 0;
while (value > 0) {
if (upper_case)
buffer[used++] = uppercase_lookup[value % base];
else
buffer[used++] = lowercase_lookup[value % base];
digit_count++;
value /= base;
if (use_separator && value > 0 && digit_count % 3 == 0)
buffer[used++] = ',';
}
for (size_t i = 0; i < used / 2; ++i)
swap(buffer[i], buffer[used - i - 1]);
return used;
}
ErrorOr<void> vformat_impl(TypeErasedFormatParams& params, FormatBuilder& builder, FormatParser& parser)
{
auto const literal = parser.consume_literal();
TRY(builder.put_literal(literal));
FormatParser::FormatSpecifier specifier;
if (!parser.consume_specifier(specifier)) {
VERIFY(parser.is_eof());
return {};
}
if (specifier.index == use_next_index)
specifier.index = params.take_next_index();
auto& parameter = params.parameters().at(specifier.index);
FormatParser argparser { specifier.flags };
TRY(parameter.formatter(params, builder, argparser, parameter.value));
TRY(vformat_impl(params, builder, parser));
return {};
}
} // namespace AK::{anonymous}
FormatParser::FormatParser(StringView input)
: GenericLexer(input)
{
}
StringView FormatParser::consume_literal()
{
auto const begin = tell();
while (!is_eof()) {
if (consume_specific("{{"sv))
continue;
if (consume_specific("}}"sv))
continue;
if (next_is(is_any_of("{}"sv)))
return m_input.substring_view(begin, tell() - begin);
consume();
}
return m_input.substring_view(begin);
}
bool FormatParser::consume_number(size_t& value)
{
value = 0;
bool consumed_at_least_one = false;
while (next_is(is_ascii_digit)) {
value *= 10;
value += parse_ascii_digit(consume());
consumed_at_least_one = true;
}
return consumed_at_least_one;
}
bool FormatParser::consume_specifier(FormatSpecifier& specifier)
{
VERIFY(!next_is('}'));
if (!consume_specific('{'))
return false;
if (!consume_number(specifier.index))
specifier.index = use_next_index;
if (consume_specific(':')) {
auto const begin = tell();
size_t level = 1;
while (level > 0) {
VERIFY(!is_eof());
if (consume_specific('{')) {
++level;
continue;
}
if (consume_specific('}')) {
--level;
continue;
}
consume();
}
specifier.flags = m_input.substring_view(begin, tell() - begin - 1);
} else {
if (!consume_specific('}'))
VERIFY_NOT_REACHED();
specifier.flags = ""sv;
}
return true;
}
bool FormatParser::consume_replacement_field(size_t& index)
{
if (!consume_specific('{'))
return false;
if (!consume_number(index))
index = use_next_index;
if (!consume_specific('}'))
VERIFY_NOT_REACHED();
return true;
}
ErrorOr<void> FormatBuilder::put_padding(char fill, size_t amount)
{
for (size_t i = 0; i < amount; ++i)
TRY(m_builder.try_append(fill));
return {};
}
ErrorOr<void> FormatBuilder::put_literal(StringView value)
{
for (size_t i = 0; i < value.length(); ++i) {
TRY(m_builder.try_append(value[i]));
if (value[i] == '{' || value[i] == '}')
++i;
}
return {};
}
ErrorOr<void> FormatBuilder::put_string(
StringView value,
Align align,
size_t min_width,
size_t max_width,
char fill)
{
auto const used_by_string = min(max_width, value.length());
auto const used_by_padding = max(min_width, used_by_string) - used_by_string;
if (used_by_string < value.length())
value = value.substring_view(0, used_by_string);
if (align == Align::Left || align == Align::Default) {
TRY(m_builder.try_append(value));
TRY(put_padding(fill, used_by_padding));
} else if (align == Align::Center) {
auto const used_by_left_padding = used_by_padding / 2;
auto const used_by_right_padding = ceil_div<size_t, size_t>(used_by_padding, 2);
TRY(put_padding(fill, used_by_left_padding));
TRY(m_builder.try_append(value));
TRY(put_padding(fill, used_by_right_padding));
} else if (align == Align::Right) {
TRY(put_padding(fill, used_by_padding));
TRY(m_builder.try_append(value));
}
return {};
}
ErrorOr<void> FormatBuilder::put_u64(
u64 value,
u8 base,
bool prefix,
bool upper_case,
bool zero_pad,
bool use_separator,
Align align,
size_t min_width,
char fill,
SignMode sign_mode,
bool is_negative)
{
if (align == Align::Default)
align = Align::Right;
Array<u8, 128> buffer;
auto const used_by_digits = convert_unsigned_to_string(value, buffer, base, upper_case, use_separator);
size_t used_by_prefix = 0;
if (align == Align::Right && zero_pad) {
// We want ByteString::formatted("{:#08x}", 32) to produce '0x00000020' instead of '0x000020'. This
// behavior differs from both fmtlib and printf, but is more intuitive.
used_by_prefix = 0;
} else {
if (is_negative || sign_mode != SignMode::OnlyIfNeeded)
used_by_prefix += 1;
if (prefix) {
if (base == 8)
used_by_prefix += 1;
else if (base == 16)
used_by_prefix += 2;
else if (base == 2)
used_by_prefix += 2;
}
}
auto const used_by_field = used_by_prefix + used_by_digits;
auto const used_by_padding = max(used_by_field, min_width) - used_by_field;
auto const put_prefix = [&]() -> ErrorOr<void> {
if (is_negative)
TRY(m_builder.try_append('-'));
else if (sign_mode == SignMode::Always)
TRY(m_builder.try_append('+'));
else if (sign_mode == SignMode::Reserved)
TRY(m_builder.try_append(' '));
if (prefix) {
if (base == 2) {
if (upper_case)
TRY(m_builder.try_append("0B"sv));
else
TRY(m_builder.try_append("0b"sv));
} else if (base == 8) {
TRY(m_builder.try_append("0"sv));
} else if (base == 16) {
if (upper_case)
TRY(m_builder.try_append("0X"sv));
else
TRY(m_builder.try_append("0x"sv));
}
}
return {};
};
auto const put_digits = [&]() -> ErrorOr<void> {
for (size_t i = 0; i < used_by_digits; ++i)
TRY(m_builder.try_append(buffer[i]));
return {};
};
if (align == Align::Left) {
auto const used_by_right_padding = used_by_padding;
TRY(put_prefix());
TRY(put_digits());
TRY(put_padding(fill, used_by_right_padding));
} else if (align == Align::Center) {
auto const used_by_left_padding = used_by_padding / 2;
auto const used_by_right_padding = ceil_div<size_t, size_t>(used_by_padding, 2);
TRY(put_padding(fill, used_by_left_padding));
TRY(put_prefix());
TRY(put_digits());
TRY(put_padding(fill, used_by_right_padding));
} else if (align == Align::Right) {
auto const used_by_left_padding = used_by_padding;
if (zero_pad) {
TRY(put_prefix());
TRY(put_padding('0', used_by_left_padding));
TRY(put_digits());
} else {
TRY(put_padding(fill, used_by_left_padding));
TRY(put_prefix());
TRY(put_digits());
}
}
return {};
}
ErrorOr<void> FormatBuilder::put_i64(
i64 value,
u8 base,
bool prefix,
bool upper_case,
bool zero_pad,
bool use_separator,
Align align,
size_t min_width,
char fill,
SignMode sign_mode)
{
auto const is_negative = value < 0;
u64 positive_value;
if (value == NumericLimits<i64>::min()) {
positive_value = static_cast<u64>(NumericLimits<i64>::max()) + 1;
} else {
positive_value = is_negative ? -value : value;
}
TRY(put_u64(positive_value, base, prefix, upper_case, zero_pad, use_separator, align, min_width, fill, sign_mode, is_negative));
return {};
}
ErrorOr<void> FormatBuilder::put_fixed_point(
bool is_negative,
i64 integer_value,
u64 fraction_value,
u64 fraction_one,
size_t precision,
u8 base,
bool upper_case,
bool zero_pad,
bool use_separator,
Align align,
size_t min_width,
size_t fraction_max_width,
char fill,
SignMode sign_mode)
{
StringBuilder string_builder;
FormatBuilder format_builder { string_builder };
if (is_negative)
integer_value = -integer_value;
TRY(format_builder.put_u64(static_cast<u64>(integer_value), base, false, upper_case, false, use_separator, Align::Right, 0, ' ', sign_mode, is_negative));
if (fraction_max_width && (zero_pad || fraction_value)) {
// FIXME: This is a terrible approximation but doing it properly would be a lot of work. If someone is up for that, a good
// place to start would be the following video from CppCon 2019:
// https://youtu.be/4P_kbF0EbZM (Stephan T. Lavavej “Floating-Point <charconv>: Making Your Code 10x Faster With C++17's Final Boss”)
if (is_negative && fraction_value)
fraction_value = fraction_one - fraction_value;
TRY(string_builder.try_append('.'));
if (base == 10) {
u64 scale = pow<u64>(5, precision);
// FIXME: overflows (not before: fraction_value = (2^precision - 1) and precision >= 20) (use wider integer type)
auto fraction = scale * fraction_value;
TRY(format_builder.put_u64(fraction, base, false, upper_case, true, use_separator, Align::Right, precision));
} else if (base == 16 || base == 8 || base == 2) {
auto bits_per_character = log2(base);
auto fraction = fraction_value << ((bits_per_character - (precision % bits_per_character)) % bits_per_character);
TRY(format_builder.put_u64(fraction, base, false, upper_case, false, use_separator, Align::Right, precision / bits_per_character + (precision % bits_per_character != 0), '0'));
} else {
VERIFY_NOT_REACHED();
}
}
auto formatted_string = string_builder.string_view();
if (fraction_max_width && (zero_pad || fraction_value)) {
auto point_index = formatted_string.find('.').value_or(0);
if (!point_index)
VERIFY_NOT_REACHED();
if (auto formatted_length = (formatted_string.length() - point_index - 1); formatted_length > fraction_max_width) {
formatted_string = formatted_string.substring_view(0, 1 + point_index + fraction_max_width);
} else {
string_builder.append_repeated('0', fraction_max_width - formatted_length);
formatted_string = string_builder.string_view();
}
if (!zero_pad)
formatted_string = formatted_string.trim("0"sv, TrimMode::Right);
if (formatted_string.ends_with('.'))
formatted_string = formatted_string.trim("."sv, TrimMode::Right);
}
TRY(put_string(formatted_string, align, min_width, NumericLimits<size_t>::max(), fill));
return {};
}
static ErrorOr<void> round_up_digits(StringBuilder& digits_builder)
{
auto digits_buffer = TRY(digits_builder.to_byte_buffer());
int current_position = digits_buffer.size() - 1;
while (current_position >= 0) {
if (digits_buffer[current_position] == '.') {
--current_position;
continue;
}
++digits_buffer[current_position];
if (digits_buffer[current_position] <= '9')
break;
digits_buffer[current_position] = '0';
--current_position;
}
digits_builder.clear();
if (current_position < 0)
TRY(digits_builder.try_append('1'));
return digits_builder.try_append(digits_buffer);
}
ErrorOr<void> FormatBuilder::put_f64_with_precision(
double value,
u8 base,
bool upper_case,
bool zero_pad,
bool use_separator,
Align align,
size_t min_width,
size_t precision,
char fill,
SignMode sign_mode,
RealNumberDisplayMode display_mode)
{
StringBuilder string_builder;
FormatBuilder format_builder { string_builder };
if (isnan(value) || isinf(value)) [[unlikely]] {
if (value < 0.0)
TRY(string_builder.try_append('-'));
else if (sign_mode == SignMode::Always)
TRY(string_builder.try_append('+'));
else if (sign_mode == SignMode::Reserved)
TRY(string_builder.try_append(' '));
if (isnan(value))
TRY(string_builder.try_append(upper_case ? "NAN"sv : "nan"sv));
else
TRY(string_builder.try_append(upper_case ? "INF"sv : "inf"sv));
TRY(put_string(string_builder.string_view(), align, min_width, NumericLimits<size_t>::max(), fill));
return {};
}
bool is_negative = value < 0.0;
if (is_negative)
value = -value;
TRY(format_builder.put_u64(static_cast<u64>(value), base, false, upper_case, false, use_separator, Align::Right, 0, ' ', sign_mode, is_negative));
value -= static_cast<i64>(value);
if (precision > 0) {
// FIXME: This is a terrible approximation but doing it properly would be a lot of work. If someone is up for that, a good
// place to start would be the following video from CppCon 2019:
// https://youtu.be/4P_kbF0EbZM (Stephan T. Lavavej “Floating-Point <charconv>: Making Your Code 10x Faster With C++17's Final Boss”)
double epsilon = 0.5;
if (!zero_pad && display_mode != RealNumberDisplayMode::FixedPoint) {
for (size_t i = 0; i < precision; ++i)
epsilon /= 10.0;
}
for (size_t digit = 0; digit < precision; ++digit) {
if (!zero_pad && display_mode != RealNumberDisplayMode::FixedPoint && value - static_cast<i64>(value) < epsilon)
break;
value *= 10.0;
epsilon *= 10.0;
if (value > NumericLimits<u32>::max())
value -= static_cast<u64>(value) - (static_cast<u64>(value) % 10);
if (digit == 0)
TRY(string_builder.try_append('.'));
TRY(string_builder.try_append('0' + (static_cast<u32>(value) % 10)));
}
}
// Round up if the following decimal is 5 or higher
if (static_cast<u64>(value * 10.0) % 10 >= 5)
TRY(round_up_digits(string_builder));
return put_string(string_builder.string_view(), align, min_width, NumericLimits<size_t>::max(), fill);
}
template<OneOf<f32, f64> T>
ErrorOr<void> FormatBuilder::put_f32_or_f64(
T value,
u8 base,
bool upper_case,
bool zero_pad,
bool use_separator,
Align align,
size_t min_width,
Optional<size_t> precision,
char fill,
SignMode sign_mode,
RealNumberDisplayMode display_mode)
{
if (precision.has_value() || base != 10)
return put_f64_with_precision(value, base, upper_case, zero_pad, use_separator, align, min_width, precision.value_or(6), fill, sign_mode, display_mode);
// No precision specified, so pick the best precision with roundtrip guarantees.
StringBuilder builder;
// Special cases: NaN, inf, -inf, 0 and -0.
auto const is_nan = isnan(value);
auto const is_inf = isinf(value);
auto const is_zero = value == static_cast<T>(0.0) || value == static_cast<T>(-0.0);
if (is_nan || is_inf || is_zero) {
if (value < 0)
TRY(builder.try_append('-'));
else if (sign_mode == SignMode::Always)
TRY(builder.try_append('+'));
else if (sign_mode == SignMode::Reserved)
TRY(builder.try_append(' '));
if (is_nan)
TRY(builder.try_append(upper_case ? "NAN"sv : "nan"sv));
else if (is_inf)
TRY(builder.try_append(upper_case ? "INF"sv : "inf"sv));
else
TRY(builder.try_append('0'));
return put_string(builder.string_view(), align, min_width, NumericLimits<size_t>::max(), fill);
}
auto const [sign, mantissa, exponent] = convert_floating_point_to_decimal_exponential_form(value);
auto convert_to_decimal_digits_array = [](auto x, auto& digits) -> size_t {
size_t length = 0;
for (; x; x /= 10)
digits[length++] = x % 10 | '0';
for (size_t i = 0; 2 * i + 1 < length; ++i)
swap(digits[i], digits[length - i - 1]);
return length;
};
Array<u8, 20> mantissa_digits;
auto mantissa_length = convert_to_decimal_digits_array(mantissa, mantissa_digits);
if (sign)
TRY(builder.try_append('-'));
else if (sign_mode == SignMode::Always)
TRY(builder.try_append('+'));
else if (sign_mode == SignMode::Reserved)
TRY(builder.try_append(' '));
auto const n = exponent + static_cast<i32>(mantissa_length);
auto const mantissa_text = StringView { mantissa_digits.span().slice(0, mantissa_length) };
size_t integral_part_end = 0;
// NOTE: Range from ECMA262, seems like an okay default.
if (n >= -5 && n <= 21) {
if (exponent >= 0) {
TRY(builder.try_append(mantissa_text));
TRY(builder.try_append_repeated('0', exponent));
integral_part_end = builder.length();
} else if (n > 0) {
TRY(builder.try_append(mantissa_text.substring_view(0, n)));
integral_part_end = builder.length();
TRY(builder.try_append('.'));
TRY(builder.try_append(mantissa_text.substring_view(n)));
} else {
TRY(builder.try_append("0."sv));
TRY(builder.try_append_repeated('0', -n));
TRY(builder.try_append(mantissa_text));
integral_part_end = 1;
}
} else {
auto const exponent_sign = n < 0 ? '-' : '+';
Array<u8, 5> exponent_digits;
auto const exponent_length = convert_to_decimal_digits_array(abs(n - 1), exponent_digits);
auto const exponent_text = StringView { exponent_digits.span().slice(0, exponent_length) };
integral_part_end = 1;
if (mantissa_length == 1) {
// <mantissa>e<exponent>
TRY(builder.try_append(mantissa_text));
TRY(builder.try_append('e'));
TRY(builder.try_append(exponent_sign));
TRY(builder.try_append(exponent_text));
} else {
// <mantissa>.<mantissa[1..]>e<exponent>
TRY(builder.try_append(mantissa_text.substring_view(0, 1)));
TRY(builder.try_append('.'));
TRY(builder.try_append(mantissa_text.substring_view(1)));
TRY(builder.try_append('e'));
TRY(builder.try_append(exponent_sign));
TRY(builder.try_append(exponent_text));
}
}
if (use_separator && integral_part_end > 3) {
// Go backwards from the end of the integral part, inserting commas every 3 consecutive digits.
StringBuilder separated_builder;
auto const string_view = builder.string_view();
for (size_t i = 0; i < integral_part_end; ++i) {
auto const index_from_end = integral_part_end - i - 1;
if (index_from_end > 0 && index_from_end != integral_part_end - 1 && index_from_end % 3 == 2)
TRY(separated_builder.try_append(','));
TRY(separated_builder.try_append(string_view[i]));
}
TRY(separated_builder.try_append(string_view.substring_view(integral_part_end)));
builder = move(separated_builder);
}
return put_string(builder.string_view(), align, min_width, NumericLimits<size_t>::max(), fill);
}
ErrorOr<void> FormatBuilder::put_f80(
long double value,
u8 base,
bool upper_case,
bool use_separator,
Align align,
size_t min_width,
size_t precision,
char fill,
SignMode sign_mode,
RealNumberDisplayMode display_mode)
{
StringBuilder string_builder;
FormatBuilder format_builder { string_builder };
if (isnan(value) || isinf(value)) [[unlikely]] {
if (value < 0.0l)
TRY(string_builder.try_append('-'));
else if (sign_mode == SignMode::Always)
TRY(string_builder.try_append('+'));
else if (sign_mode == SignMode::Reserved)
TRY(string_builder.try_append(' '));
if (isnan(value))
TRY(string_builder.try_append(upper_case ? "NAN"sv : "nan"sv));
else
TRY(string_builder.try_append(upper_case ? "INF"sv : "inf"sv));
TRY(put_string(string_builder.string_view(), align, min_width, NumericLimits<size_t>::max(), fill));
return {};
}
bool is_negative = value < 0.0l;
if (is_negative)
value = -value;
TRY(format_builder.put_u64(static_cast<u64>(value), base, false, upper_case, false, use_separator, Align::Right, 0, ' ', sign_mode, is_negative));
value -= static_cast<i64>(value);
if (precision > 0) {
// FIXME: This is a terrible approximation but doing it properly would be a lot of work. If someone is up for that, a good
// place to start would be the following video from CppCon 2019:
// https://youtu.be/4P_kbF0EbZM (Stephan T. Lavavej “Floating-Point <charconv>: Making Your Code 10x Faster With C++17's Final Boss”)
long double epsilon = 0.5l;
if (display_mode != RealNumberDisplayMode::FixedPoint) {
for (size_t i = 0; i < precision; ++i)
epsilon /= 10.0l;
}
for (size_t digit = 0; digit < precision; ++digit) {
if (display_mode != RealNumberDisplayMode::FixedPoint && value - static_cast<i64>(value) < epsilon)
break;
value *= 10.0l;
epsilon *= 10.0l;
if (value > NumericLimits<u32>::max())
value -= static_cast<u64>(value) - (static_cast<u64>(value) % 10);
if (digit == 0)
TRY(string_builder.try_append('.'));
TRY(string_builder.try_append('0' + (static_cast<u32>(value) % 10)));
}
}
// Round up if the following decimal is 5 or higher
if (static_cast<u64>(value * 10.0l) % 10 >= 5)
TRY(round_up_digits(string_builder));
TRY(put_string(string_builder.string_view(), align, min_width, NumericLimits<size_t>::max(), fill));
return {};
}
ErrorOr<void> FormatBuilder::put_hexdump(ReadonlyBytes bytes, size_t width, char fill)
{
auto put_char_view = [&](auto i) -> ErrorOr<void> {
TRY(put_padding(fill, 4));
for (size_t j = i - min(i, width); j < i; ++j) {
auto ch = bytes[j];
TRY(m_builder.try_append(ch >= 32 && ch <= 127 ? ch : '.')); // silly hack
}
return {};
};
for (size_t i = 0; i < bytes.size(); ++i) {
if (width > 0) {
if (i % width == 0 && i) {
TRY(put_char_view(i));
TRY(put_literal("\n"sv));
}
}
TRY(put_u64(bytes[i], 16, false, false, true, false, Align::Right, 2));
}
if (width > 0)
TRY(put_char_view(bytes.size()));
return {};
}
ErrorOr<void> vformat(StringBuilder& builder, StringView fmtstr, TypeErasedFormatParams& params)
{
FormatBuilder fmtbuilder { builder };
FormatParser parser { fmtstr };
TRY(vformat_impl(params, fmtbuilder, parser));
return {};
}
void StandardFormatter::parse(TypeErasedFormatParams& params, FormatParser& parser)
{
if ("<^>"sv.contains(parser.peek(1))) {
VERIFY(!parser.next_is(is_any_of("{}"sv)));
m_fill = parser.consume();
}
if (parser.consume_specific('<'))
m_align = FormatBuilder::Align::Left;
else if (parser.consume_specific('^'))
m_align = FormatBuilder::Align::Center;
else if (parser.consume_specific('>'))
m_align = FormatBuilder::Align::Right;
if (parser.consume_specific('-'))
m_sign_mode = FormatBuilder::SignMode::OnlyIfNeeded;
else if (parser.consume_specific('+'))
m_sign_mode = FormatBuilder::SignMode::Always;
else if (parser.consume_specific(' '))
m_sign_mode = FormatBuilder::SignMode::Reserved;
if (parser.consume_specific('#'))
m_alternative_form = true;
if (parser.consume_specific('\''))
m_use_separator = true;
if (parser.consume_specific('0'))
m_zero_pad = true;
if (size_t index = 0; parser.consume_replacement_field(index)) {
if (index == use_next_index)
index = params.take_next_index();
m_width = params.parameters().at(index).to_size();
} else if (size_t width = 0; parser.consume_number(width)) {
m_width = width;
}
if (parser.consume_specific('.')) {
if (size_t index = 0; parser.consume_replacement_field(index)) {
if (index == use_next_index)
index = params.take_next_index();
m_precision = params.parameters().at(index).to_size();
} else if (size_t precision = 0; parser.consume_number(precision)) {
m_precision = precision;
}
}
if (parser.consume_specific('b'))
m_mode = Mode::Binary;
else if (parser.consume_specific('B'))
m_mode = Mode::BinaryUppercase;
else if (parser.consume_specific('d'))
m_mode = Mode::Decimal;
else if (parser.consume_specific('o'))
m_mode = Mode::Octal;
else if (parser.consume_specific('x'))
m_mode = Mode::Hexadecimal;
else if (parser.consume_specific('X'))
m_mode = Mode::HexadecimalUppercase;
else if (parser.consume_specific('c'))
m_mode = Mode::Character;
else if (parser.consume_specific('s'))
m_mode = Mode::String;
else if (parser.consume_specific('p'))
m_mode = Mode::Pointer;
else if (parser.consume_specific('f'))
m_mode = Mode::FixedPoint;
else if (parser.consume_specific('a'))
m_mode = Mode::Hexfloat;
else if (parser.consume_specific('A'))
m_mode = Mode::HexfloatUppercase;
else if (parser.consume_specific("hex-dump"sv))
m_mode = Mode::HexDump;
if (!parser.is_eof())
dbgln("{} did not consume '{}'", __PRETTY_FUNCTION__, parser.remaining());
VERIFY(parser.is_eof());
}
ErrorOr<void> Formatter<StringView>::format(FormatBuilder& builder, StringView value)
{
if (m_sign_mode != FormatBuilder::SignMode::Default)
VERIFY_NOT_REACHED();
if (m_zero_pad)
VERIFY_NOT_REACHED();
if (m_mode != Mode::Default && m_mode != Mode::String && m_mode != Mode::Character && m_mode != Mode::HexDump)
VERIFY_NOT_REACHED();
m_width = m_width.value_or(0);
m_precision = m_precision.value_or(NumericLimits<size_t>::max());
if (m_mode == Mode::HexDump)
return builder.put_hexdump(value.bytes(), m_width.value(), m_fill);
return builder.put_string(value, m_align, m_width.value(), m_precision.value(), m_fill);
}
ErrorOr<void> Formatter<FormatString>::vformat(FormatBuilder& builder, StringView fmtstr, TypeErasedFormatParams& params)
{
StringBuilder string_builder;
TRY(AK::vformat(string_builder, fmtstr, params));
TRY(Formatter<StringView>::format(builder, string_builder.string_view()));
return {};
}
template<Integral T>
ErrorOr<void> Formatter<T>::format(FormatBuilder& builder, T value)
{
if (m_mode == Mode::Character) {
// FIXME: We just support ASCII for now, in the future maybe unicode?
// VERIFY(value >= 0 && value <= 127);
m_mode = Mode::String;
Formatter<StringView> formatter { *this };
// convert value to single byte, important for big-endian because the LSB is the last byte.
VERIFY(value >= 0 && value <= 127);
char const c = (value & 0x7f);
return formatter.format(builder, StringView { &c, 1 });
}
if (m_precision.has_value())
VERIFY_NOT_REACHED();
if (m_mode == Mode::Pointer) {
if (m_sign_mode != FormatBuilder::SignMode::Default)
VERIFY_NOT_REACHED();
if (m_align != FormatBuilder::Align::Default)
VERIFY_NOT_REACHED();
if (m_alternative_form)
VERIFY_NOT_REACHED();
if (m_width.has_value())
VERIFY_NOT_REACHED();
m_mode = Mode::Hexadecimal;
m_alternative_form = true;
m_width = 2 * sizeof(void*);
m_zero_pad = true;
}
u8 base = 0;
bool upper_case = false;
if (m_mode == Mode::Binary) {
base = 2;
} else if (m_mode == Mode::BinaryUppercase) {
base = 2;
upper_case = true;
} else if (m_mode == Mode::Octal) {
base = 8;
} else if (m_mode == Mode::Decimal || m_mode == Mode::Default) {
base = 10;
} else if (m_mode == Mode::Hexadecimal) {
base = 16;
} else if (m_mode == Mode::HexadecimalUppercase) {
base = 16;
upper_case = true;
} else if (m_mode == Mode::HexDump) {
m_width = m_width.value_or(32);
return builder.put_hexdump({ &value, sizeof(value) }, m_width.value(), m_fill);
} else {
VERIFY_NOT_REACHED();
}
m_width = m_width.value_or(0);
if constexpr (IsSame<MakeUnsigned<T>, T>)
return builder.put_u64(value, base, m_alternative_form, upper_case, m_zero_pad, m_use_separator, m_align, m_width.value(), m_fill, m_sign_mode);
else
return builder.put_i64(value, base, m_alternative_form, upper_case, m_zero_pad, m_use_separator, m_align, m_width.value(), m_fill, m_sign_mode);
}
ErrorOr<void> Formatter<char>::format(FormatBuilder& builder, char value)
{
if (m_mode == Mode::Binary || m_mode == Mode::BinaryUppercase || m_mode == Mode::Decimal || m_mode == Mode::Octal || m_mode == Mode::Hexadecimal || m_mode == Mode::HexadecimalUppercase) {
// Trick: signed char != char. (Sometimes weird features are actually helpful.)
Formatter<signed char> formatter { *this };
return formatter.format(builder, static_cast<signed char>(value));
} else {
Formatter<StringView> formatter { *this };
return formatter.format(builder, { &value, 1 });
}
}
ErrorOr<void> Formatter<wchar_t>::format(FormatBuilder& builder, wchar_t value)
{
if (m_mode == Mode::Binary || m_mode == Mode::BinaryUppercase || m_mode == Mode::Decimal || m_mode == Mode::Octal || m_mode == Mode::Hexadecimal || m_mode == Mode::HexadecimalUppercase) {
Formatter<u32> formatter { *this };
return formatter.format(builder, static_cast<u32>(value));
} else {
StringBuilder codepoint;
codepoint.append_code_point(value);
Formatter<StringView> formatter { *this };
return formatter.format(builder, codepoint.string_view());
}
}
ErrorOr<void> Formatter<bool>::format(FormatBuilder& builder, bool value)
{
if (m_mode == Mode::Binary || m_mode == Mode::BinaryUppercase || m_mode == Mode::Decimal || m_mode == Mode::Octal || m_mode == Mode::Hexadecimal || m_mode == Mode::HexadecimalUppercase) {
Formatter<u8> formatter { *this };
return formatter.format(builder, static_cast<u8>(value));
} else if (m_mode == Mode::HexDump) {
return builder.put_hexdump({ &value, sizeof(value) }, m_width.value_or(32), m_fill);
} else {
Formatter<StringView> formatter { *this };
return formatter.format(builder, value ? "true"sv : "false"sv);
}
}
ErrorOr<void> Formatter<long double>::format(FormatBuilder& builder, long double value)
{
u8 base;
bool upper_case;
FormatBuilder::RealNumberDisplayMode real_number_display_mode = FormatBuilder::RealNumberDisplayMode::General;
if (m_mode == Mode::Default || m_mode == Mode::FixedPoint) {
base = 10;
upper_case = false;
if (m_mode == Mode::FixedPoint)
real_number_display_mode = FormatBuilder::RealNumberDisplayMode::FixedPoint;
} else if (m_mode == Mode::Hexfloat) {
base = 16;