ladybird/AK/Format.h
sin-ack 3f3f45580a Everywhere: Add sv suffix to strings relying on StringView(char const*)
Each of these strings would previously rely on StringView's char const*
constructor overload, which would call __builtin_strlen on the string.
Since we now have operator ""sv, we can replace these with much simpler
versions. This opens the door to being able to remove
StringView(char const*).

No functional changes.
2022-07-12 23:11:35 +02:00

723 lines
21 KiB
C++

/*
* Copyright (c) 2020, the SerenityOS developers.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/CheckedFormatString.h>
#include <AK/AllOf.h>
#include <AK/AnyOf.h>
#include <AK/Array.h>
#include <AK/Error.h>
#include <AK/FixedPoint.h>
#include <AK/Forward.h>
#include <AK/Optional.h>
#include <AK/StringView.h>
#ifndef KERNEL
# include <stdio.h>
# include <string.h>
#endif
namespace AK {
class TypeErasedFormatParams;
class FormatParser;
class FormatBuilder;
template<typename T, typename = void>
struct Formatter {
using __no_formatter_defined = void;
};
template<typename T, typename = void>
inline constexpr bool HasFormatter = true;
template<typename T>
inline constexpr bool HasFormatter<T, typename Formatter<T>::__no_formatter_defined> = false;
constexpr size_t max_format_arguments = 256;
struct TypeErasedParameter {
enum class Type {
UInt8,
UInt16,
UInt32,
UInt64,
Int8,
Int16,
Int32,
Int64,
Custom
};
template<size_t size, bool is_unsigned>
static consteval Type get_type_from_size()
{
if constexpr (is_unsigned) {
if constexpr (size == 1)
return Type::UInt8;
if constexpr (size == 2)
return Type::UInt16;
if constexpr (size == 4)
return Type::UInt32;
if constexpr (size == 8)
return Type::UInt64;
} else {
if constexpr (size == 1)
return Type::Int8;
if constexpr (size == 2)
return Type::Int16;
if constexpr (size == 4)
return Type::Int32;
if constexpr (size == 8)
return Type::Int64;
}
VERIFY_NOT_REACHED();
}
template<typename T>
static consteval Type get_type()
{
if constexpr (IsIntegral<T>)
return get_type_from_size<sizeof(T), IsUnsigned<T>>();
else
return Type::Custom;
}
template<typename Visitor>
constexpr auto visit(Visitor&& visitor) const
{
switch (type) {
case TypeErasedParameter::Type::UInt8:
return visitor(*static_cast<u8 const*>(value));
case TypeErasedParameter::Type::UInt16:
return visitor(*static_cast<u16 const*>(value));
case TypeErasedParameter::Type::UInt32:
return visitor(*static_cast<u32 const*>(value));
case TypeErasedParameter::Type::UInt64:
return visitor(*static_cast<u64 const*>(value));
case TypeErasedParameter::Type::Int8:
return visitor(*static_cast<i8 const*>(value));
case TypeErasedParameter::Type::Int16:
return visitor(*static_cast<i16 const*>(value));
case TypeErasedParameter::Type::Int32:
return visitor(*static_cast<i32 const*>(value));
case TypeErasedParameter::Type::Int64:
return visitor(*static_cast<i64 const*>(value));
default:
TODO();
}
}
constexpr size_t to_size() const
{
return visit([]<typename T>(T value) {
if constexpr (sizeof(T) > sizeof(size_t))
VERIFY(value < NumericLimits<size_t>::max());
if constexpr (IsSigned<T>)
VERIFY(value > 0);
return static_cast<size_t>(value);
});
}
// FIXME: Getters and setters.
void const* value;
Type type;
ErrorOr<void> (*formatter)(TypeErasedFormatParams&, FormatBuilder&, FormatParser&, void const* value);
};
class FormatBuilder {
public:
enum class Align {
Default,
Left,
Center,
Right,
};
enum class SignMode {
OnlyIfNeeded,
Always,
Reserved,
Default = OnlyIfNeeded,
};
explicit FormatBuilder(StringBuilder& builder)
: m_builder(builder)
{
}
ErrorOr<void> put_padding(char fill, size_t amount);
ErrorOr<void> put_literal(StringView value);
ErrorOr<void> put_string(
StringView value,
Align align = Align::Left,
size_t min_width = 0,
size_t max_width = NumericLimits<size_t>::max(),
char fill = ' ');
ErrorOr<void> put_u64(
u64 value,
u8 base = 10,
bool prefix = false,
bool upper_case = false,
bool zero_pad = false,
Align align = Align::Right,
size_t min_width = 0,
char fill = ' ',
SignMode sign_mode = SignMode::OnlyIfNeeded,
bool is_negative = false);
ErrorOr<void> put_i64(
i64 value,
u8 base = 10,
bool prefix = false,
bool upper_case = false,
bool zero_pad = false,
Align align = Align::Right,
size_t min_width = 0,
char fill = ' ',
SignMode sign_mode = SignMode::OnlyIfNeeded);
ErrorOr<void> put_fixed_point(
i64 integer_value,
u64 fraction_value,
u64 fraction_one,
u8 base = 10,
bool upper_case = false,
bool zero_pad = false,
Align align = Align::Right,
size_t min_width = 0,
size_t precision = 6,
char fill = ' ',
SignMode sign_mode = SignMode::OnlyIfNeeded);
#ifndef KERNEL
ErrorOr<void> put_f80(
long double value,
u8 base = 10,
bool upper_case = false,
Align align = Align::Right,
size_t min_width = 0,
size_t precision = 6,
char fill = ' ',
SignMode sign_mode = SignMode::OnlyIfNeeded);
ErrorOr<void> put_f64(
double value,
u8 base = 10,
bool upper_case = false,
bool zero_pad = false,
Align align = Align::Right,
size_t min_width = 0,
size_t precision = 6,
char fill = ' ',
SignMode sign_mode = SignMode::OnlyIfNeeded);
#endif
ErrorOr<void> put_hexdump(
ReadonlyBytes,
size_t width,
char fill = ' ');
StringBuilder const& builder() const
{
return m_builder;
}
StringBuilder& builder() { return m_builder; }
private:
StringBuilder& m_builder;
};
class TypeErasedFormatParams {
public:
Span<const TypeErasedParameter> parameters() const { return m_parameters; }
void set_parameters(Span<const TypeErasedParameter> parameters) { m_parameters = parameters; }
size_t take_next_index() { return m_next_index++; }
private:
Span<const TypeErasedParameter> m_parameters;
size_t m_next_index { 0 };
};
template<typename T>
ErrorOr<void> __format_value(TypeErasedFormatParams& params, FormatBuilder& builder, FormatParser& parser, void const* value)
{
Formatter<T> formatter;
formatter.parse(params, parser);
return formatter.format(builder, *static_cast<const T*>(value));
}
template<typename... Parameters>
class VariadicFormatParams : public TypeErasedFormatParams {
public:
static_assert(sizeof...(Parameters) <= max_format_arguments);
explicit VariadicFormatParams(Parameters const&... parameters)
: m_data({ TypeErasedParameter { &parameters, TypeErasedParameter::get_type<Parameters>(), __format_value<Parameters> }... })
{
this->set_parameters(m_data);
}
private:
Array<TypeErasedParameter, sizeof...(Parameters)> m_data;
};
// We use the same format for most types for consistency. This is taken directly from
// std::format. One difference is that we are not counting the width or sign towards the
// total width when calculating zero padding for numbers.
// https://en.cppreference.com/w/cpp/utility/format/formatter#Standard_format_specification
struct StandardFormatter {
enum class Mode {
Default,
Binary,
BinaryUppercase,
Decimal,
Octal,
Hexadecimal,
HexadecimalUppercase,
Character,
String,
Pointer,
Float,
Hexfloat,
HexfloatUppercase,
HexDump,
};
FormatBuilder::Align m_align = FormatBuilder::Align::Default;
FormatBuilder::SignMode m_sign_mode = FormatBuilder::SignMode::OnlyIfNeeded;
Mode m_mode = Mode::Default;
bool m_alternative_form = false;
char m_fill = ' ';
bool m_zero_pad = false;
Optional<size_t> m_width;
Optional<size_t> m_precision;
void parse(TypeErasedFormatParams&, FormatParser&);
};
template<Integral T>
struct Formatter<T> : StandardFormatter {
Formatter() = default;
explicit Formatter(StandardFormatter formatter)
: StandardFormatter(move(formatter))
{
}
ErrorOr<void> format(FormatBuilder&, T);
};
template<>
struct Formatter<StringView> : StandardFormatter {
Formatter() = default;
explicit Formatter(StandardFormatter formatter)
: StandardFormatter(move(formatter))
{
}
ErrorOr<void> format(FormatBuilder&, StringView);
};
template<typename T, size_t inline_capacity>
requires(HasFormatter<T>) struct Formatter<Vector<T, inline_capacity>> : StandardFormatter {
Formatter() = default;
explicit Formatter(StandardFormatter formatter)
: StandardFormatter(move(formatter))
{
}
ErrorOr<void> format(FormatBuilder& builder, Vector<T> value)
{
if (m_mode == Mode::Pointer) {
Formatter<FlatPtr> formatter { *this };
TRY(formatter.format(builder, reinterpret_cast<FlatPtr>(value.data())));
return {};
}
if (m_sign_mode != FormatBuilder::SignMode::Default)
VERIFY_NOT_REACHED();
if (m_alternative_form)
VERIFY_NOT_REACHED();
if (m_zero_pad)
VERIFY_NOT_REACHED();
if (m_mode != Mode::Default)
VERIFY_NOT_REACHED();
if (m_width.has_value() && m_precision.has_value())
VERIFY_NOT_REACHED();
m_width = m_width.value_or(0);
m_precision = m_precision.value_or(NumericLimits<size_t>::max());
Formatter<T> content_fmt;
TRY(builder.put_literal("[ "sv));
bool first = true;
for (auto& content : value) {
if (!first) {
TRY(builder.put_literal(", "sv));
content_fmt = Formatter<T> {};
}
first = false;
TRY(content_fmt.format(builder, content));
}
TRY(builder.put_literal(" ]"sv));
return {};
}
};
template<>
struct Formatter<ReadonlyBytes> : Formatter<StringView> {
ErrorOr<void> format(FormatBuilder& builder, ReadonlyBytes value)
{
if (m_mode == Mode::Pointer) {
Formatter<FlatPtr> formatter { *this };
return formatter.format(builder, reinterpret_cast<FlatPtr>(value.data()));
}
if (m_mode == Mode::Default || m_mode == Mode::HexDump) {
m_mode = Mode::HexDump;
return Formatter<StringView>::format(builder, value);
}
return Formatter<StringView>::format(builder, value);
}
};
template<>
struct Formatter<Bytes> : Formatter<ReadonlyBytes> {
};
// FIXME: Printing raw char pointers is inherently dangerous. Remove this and
// its users and prefer StringView over it.
template<>
struct Formatter<char const*> : Formatter<StringView> {
ErrorOr<void> format(FormatBuilder& builder, char const* value)
{
if (m_mode == Mode::Pointer) {
Formatter<FlatPtr> formatter { *this };
return formatter.format(builder, reinterpret_cast<FlatPtr>(value));
}
return Formatter<StringView>::format(builder, value != nullptr ? StringView { value, __builtin_strlen(value) } : "(null)"sv);
}
};
template<>
struct Formatter<char*> : Formatter<char const*> {
};
template<size_t Size>
struct Formatter<char[Size]> : Formatter<char const*> {
};
template<size_t Size>
struct Formatter<unsigned char[Size]> : Formatter<StringView> {
ErrorOr<void> format(FormatBuilder& builder, unsigned char const* value)
{
if (m_mode == Mode::Pointer) {
Formatter<FlatPtr> formatter { *this };
return formatter.format(builder, reinterpret_cast<FlatPtr>(value));
}
return Formatter<StringView>::format(builder, { value, Size });
}
};
template<>
struct Formatter<String> : Formatter<StringView> {
};
template<>
struct Formatter<FlyString> : Formatter<StringView> {
};
template<typename T>
struct Formatter<T*> : StandardFormatter {
ErrorOr<void> format(FormatBuilder& builder, T* value)
{
if (m_mode == Mode::Default)
m_mode = Mode::Pointer;
Formatter<FlatPtr> formatter { *this };
return formatter.format(builder, reinterpret_cast<FlatPtr>(value));
}
};
template<>
struct Formatter<char> : StandardFormatter {
ErrorOr<void> format(FormatBuilder&, char);
};
template<>
struct Formatter<wchar_t> : StandardFormatter {
ErrorOr<void> format(FormatBuilder& builder, wchar_t);
};
template<>
struct Formatter<bool> : StandardFormatter {
ErrorOr<void> format(FormatBuilder&, bool);
};
#ifndef KERNEL
template<>
struct Formatter<float> : StandardFormatter {
ErrorOr<void> format(FormatBuilder&, float value);
};
template<>
struct Formatter<double> : StandardFormatter {
Formatter() = default;
explicit Formatter(StandardFormatter formatter)
: StandardFormatter(formatter)
{
}
ErrorOr<void> format(FormatBuilder&, double);
};
template<>
struct Formatter<long double> : StandardFormatter {
Formatter() = default;
explicit Formatter(StandardFormatter formatter)
: StandardFormatter(formatter)
{
}
ErrorOr<void> format(FormatBuilder&, long double value);
};
#endif
template<size_t precision, typename Underlying>
struct Formatter<FixedPoint<precision, Underlying>> : StandardFormatter {
Formatter() = default;
explicit Formatter(StandardFormatter formatter)
: StandardFormatter(formatter)
{
}
ErrorOr<void> format(FormatBuilder& builder, FixedPoint<precision, Underlying> value)
{
u8 base;
bool upper_case;
if (m_mode == Mode::Default || m_mode == Mode::Float) {
base = 10;
upper_case = false;
} else if (m_mode == Mode::Hexfloat) {
base = 16;
upper_case = false;
} else if (m_mode == Mode::HexfloatUppercase) {
base = 16;
upper_case = true;
} else {
VERIFY_NOT_REACHED();
}
m_width = m_width.value_or(0);
m_precision = m_precision.value_or(6);
i64 integer = value.ltrunk();
constexpr u64 one = static_cast<Underlying>(1) << precision;
u64 fraction_raw = value.raw() & (one - 1);
return builder.put_fixed_point(integer, fraction_raw, one, base, upper_case, m_zero_pad, m_align, m_width.value(), m_precision.value(), m_fill, m_sign_mode);
}
};
template<>
struct Formatter<std::nullptr_t> : Formatter<FlatPtr> {
ErrorOr<void> format(FormatBuilder& builder, std::nullptr_t)
{
if (m_mode == Mode::Default)
m_mode = Mode::Pointer;
return Formatter<FlatPtr>::format(builder, 0);
}
};
ErrorOr<void> vformat(StringBuilder&, StringView fmtstr, TypeErasedFormatParams&);
#ifndef KERNEL
void vout(FILE*, StringView fmtstr, TypeErasedFormatParams&, bool newline = false);
template<typename... Parameters>
void out(FILE* file, CheckedFormatString<Parameters...>&& fmtstr, Parameters const&... parameters)
{
VariadicFormatParams variadic_format_params { parameters... };
vout(file, fmtstr.view(), variadic_format_params);
}
template<typename... Parameters>
void outln(FILE* file, CheckedFormatString<Parameters...>&& fmtstr, Parameters const&... parameters)
{
VariadicFormatParams variadic_format_params { parameters... };
vout(file, fmtstr.view(), variadic_format_params, true);
}
inline void outln(FILE* file) { fputc('\n', file); }
template<typename... Parameters>
void out(CheckedFormatString<Parameters...>&& fmtstr, Parameters const&... parameters) { out(stdout, move(fmtstr), parameters...); }
template<typename... Parameters>
void outln(CheckedFormatString<Parameters...>&& fmtstr, Parameters const&... parameters) { outln(stdout, move(fmtstr), parameters...); }
inline void outln() { outln(stdout); }
# define outln_if(flag, fmt, ...) \
do { \
if constexpr (flag) \
outln(fmt, ##__VA_ARGS__); \
} while (0)
template<typename... Parameters>
void warn(CheckedFormatString<Parameters...>&& fmtstr, Parameters const&... parameters)
{
out(stderr, move(fmtstr), parameters...);
}
template<typename... Parameters>
void warnln(CheckedFormatString<Parameters...>&& fmtstr, Parameters const&... parameters) { outln(stderr, move(fmtstr), parameters...); }
inline void warnln() { outln(stderr); }
# define warnln_if(flag, fmt, ...) \
do { \
if constexpr (flag) \
warnln(fmt, ##__VA_ARGS__); \
} while (0)
#endif
void vdbgln(StringView fmtstr, TypeErasedFormatParams&);
template<typename... Parameters>
void dbgln(CheckedFormatString<Parameters...>&& fmtstr, Parameters const&... parameters)
{
VariadicFormatParams variadic_format_params { parameters... };
vdbgln(fmtstr.view(), variadic_format_params);
}
inline void dbgln() { dbgln(""); }
void set_debug_enabled(bool);
#ifdef KERNEL
void vdmesgln(StringView fmtstr, TypeErasedFormatParams&);
template<typename... Parameters>
void dmesgln(CheckedFormatString<Parameters...>&& fmt, Parameters const&... parameters)
{
VariadicFormatParams variadic_format_params { parameters... };
vdmesgln(fmt.view(), variadic_format_params);
}
void v_critical_dmesgln(StringView fmtstr, TypeErasedFormatParams&);
// be very careful to not cause any allocations here, since we could be in
// a very unstable situation
template<typename... Parameters>
void critical_dmesgln(CheckedFormatString<Parameters...>&& fmt, Parameters const&... parameters)
{
VariadicFormatParams variadic_format_params { parameters... };
v_critical_dmesgln(fmt.view(), variadic_format_params);
}
#endif
template<typename T>
class FormatIfSupported {
public:
explicit FormatIfSupported(const T& value)
: m_value(value)
{
}
const T& value() const { return m_value; }
private:
const T& m_value;
};
template<typename T, bool Supported = false>
struct __FormatIfSupported : Formatter<StringView> {
ErrorOr<void> format(FormatBuilder& builder, FormatIfSupported<T> const&)
{
return Formatter<StringView>::format(builder, "?"sv);
}
};
template<typename T>
struct __FormatIfSupported<T, true> : Formatter<T> {
ErrorOr<void> format(FormatBuilder& builder, FormatIfSupported<T> const& value)
{
return Formatter<T>::format(builder, value.value());
}
};
template<typename T>
struct Formatter<FormatIfSupported<T>> : __FormatIfSupported<T, HasFormatter<T>> {
};
// This is a helper class, the idea is that if you want to implement a formatter you can inherit
// from this class to "break down" the formatting.
struct FormatString {
};
template<>
struct Formatter<FormatString> : Formatter<StringView> {
template<typename... Parameters>
ErrorOr<void> format(FormatBuilder& builder, StringView fmtstr, Parameters const&... parameters)
{
VariadicFormatParams variadic_format_params { parameters... };
return vformat(builder, fmtstr, variadic_format_params);
}
ErrorOr<void> vformat(FormatBuilder& builder, StringView fmtstr, TypeErasedFormatParams& params);
};
template<>
struct Formatter<Error> : Formatter<FormatString> {
ErrorOr<void> format(FormatBuilder& builder, Error const& error)
{
#if defined(__serenity__) && defined(KERNEL)
if (error.is_errno())
return Formatter<FormatString>::format(builder, "Error(errno={})"sv, error.code());
return Formatter<FormatString>::format(builder, "Error({})"sv, error.string_literal());
#else
if (error.is_syscall())
return Formatter<FormatString>::format(builder, "{}: {} (errno={})"sv, error.string_literal(), strerror(error.code()), error.code());
if (error.is_errno())
return Formatter<FormatString>::format(builder, "{} (errno={})"sv, strerror(error.code()), error.code());
return Formatter<FormatString>::format(builder, "{}"sv, error.string_literal());
#endif
}
};
template<typename T, typename ErrorType>
struct Formatter<ErrorOr<T, ErrorType>> : Formatter<FormatString> {
ErrorOr<void> format(FormatBuilder& builder, ErrorOr<T, ErrorType> const& error_or)
{
if (error_or.is_error())
return Formatter<FormatString>::format(builder, "{}"sv, error_or.error());
return Formatter<FormatString>::format(builder, "{{{}}}"sv, error_or.value());
}
};
} // namespace AK
#ifdef KERNEL
using AK::critical_dmesgln;
using AK::dmesgln;
#else
using AK::out;
using AK::outln;
using AK::warn;
using AK::warnln;
#endif
using AK::dbgln;
using AK::CheckedFormatString;
using AK::FormatIfSupported;
using AK::FormatString;
#define dbgln_if(flag, fmt, ...) \
do { \
if constexpr (flag) \
dbgln(fmt, ##__VA_ARGS__); \
} while (0)