tomlplusplus/include/toml++/impl/unicode.h

//# This file is a part of toml++ and is subject to the the terms of the MIT license.
//# Copyright (c) Mark Gillard <mark.gillard@outlook.com.au>
//# See https://github.com/marzer/tomlplusplus/blob/master/LICENSE for the full license text.
// SPDX-License-Identifier: MIT
#pragma once

#include "unicode_autogenerated.h"
#include "header_start.h"
/// \cond

TOML_IMPL_NAMESPACE_START
{
	TOML_CONST_GETTER
	constexpr bool is_string_delimiter(char32_t c) noexcept
	{
		return c == U'"' || c == U'\'';
	}

	TOML_CONST_GETTER
	constexpr bool is_ascii_letter(char32_t c) noexcept
	{
		return (c >= U'a' && c <= U'z') || (c >= U'A' && c <= U'Z');
	}

	TOML_CONST_GETTER
	constexpr bool is_binary_digit(char32_t c) noexcept
	{
		return c == U'0' || c == U'1';
	}

	TOML_CONST_GETTER
	constexpr bool is_octal_digit(char32_t c) noexcept
	{
		return (c >= U'0' && c <= U'7');
	}

	TOML_CONST_GETTER
	constexpr bool is_decimal_digit(char32_t c) noexcept
	{
		return (c >= U'0' && c <= U'9');
	}

	TOML_CONST_GETTER
	constexpr bool is_hexadecimal_digit(char32_t c) noexcept
	{
		return U'0' <= c && c <= U'f' && (1ull << (static_cast<uint_least64_t>(c) - 0x30u)) & 0x7E0000007E03FFull;
	}

	template <typename T>
	TOML_CONST_GETTER
	constexpr uint_least32_t hex_to_dec(const T c) noexcept
	{
		if constexpr (std::is_same_v<remove_cvref<T>, uint_least32_t>)
			return c >= 0x41u					 // >= 'A'
					 ? 10u + (c | 0x20u) - 0x61u // - 'a'
					 : c - 0x30u				 // - '0'
				;
		else
			return hex_to_dec(static_cast<uint_least32_t>(c));
	}

	TOML_CONST_GETTER
	constexpr bool is_bare_key_character(char32_t c) noexcept
	{
		return is_ascii_bare_key_character(c)
#if TOML_LANG_UNRELEASED // toml/issues/687 (unicode bare keys)
			|| is_non_ascii_bare_key_character(c)
#endif
			;
	}

	TOML_CONST_GETTER
	constexpr bool is_value_terminator(char32_t c) noexcept
	{
		return is_whitespace(c) || c == U']' || c == U'}' || c == U',' || c == U'#';
	}

	TOML_CONST_GETTER
	constexpr bool is_control_character(char c) noexcept
	{
		return c <= '\u001F' || c == '\u007F';
	}

	TOML_CONST_GETTER
	constexpr bool is_control_character(char32_t c) noexcept
	{
		return c <= U'\u001F' || c == U'\u007F';
	}

	TOML_CONST_GETTER
	constexpr bool is_nontab_control_character(char32_t c) noexcept
	{
		return c <= U'\u0008' || (c >= U'\u000A' && c <= U'\u001F') || c == U'\u007F';
	}

	TOML_CONST_GETTER
	constexpr bool is_unicode_surrogate(char32_t c) noexcept
	{
		return c >= 0xD800u && c <= 0xDFFF;
	}

	struct utf8_decoder
	{
		// utf8_decoder based on this: https://bjoern.hoehrmann.de/utf-8/decoder/dfa/
		// Copyright (c) 2008-2009 Bjoern Hoehrmann <bjoern@hoehrmann.de>

		uint_least32_t state{};
		char32_t codepoint{};

		static constexpr uint8_t state_table[]{
			0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,
			0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,
			0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,
			0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,
			0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	0,	1,	1,	1,	1,	1,	1,	1,
			1,	1,	1,	1,	1,	1,	1,	1,	1,	9,	9,	9,	9,	9,	9,	9,	9,	9,	9,	9,	9,	9,	9,	9,	9,	7,	7,
			7,	7,	7,	7,	7,	7,	7,	7,	7,	7,	7,	7,	7,	7,	7,	7,	7,	7,	7,	7,	7,	7,	7,	7,	7,	7,	7,
			7,	7,	7,	8,	8,	2,	2,	2,	2,	2,	2,	2,	2,	2,	2,	2,	2,	2,	2,	2,	2,	2,	2,	2,	2,	2,	2,
			2,	2,	2,	2,	2,	2,	2,	2,	10, 3,	3,	3,	3,	3,	3,	3,	3,	3,	3,	3,	3,	4,	3,	3,	11, 6,	6,
			6,	5,	8,	8,	8,	8,	8,	8,	8,	8,	8,	8,	8,

			0,	12, 24, 36, 60, 96, 84, 12, 12, 12, 48, 72, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 0,	12,
			12, 12, 12, 12, 0,	12, 0,	12, 12, 12, 24, 12, 12, 12, 12, 12, 24, 12, 24, 12, 12, 12, 12, 12, 12, 12, 12,
			12, 24, 12, 12, 12, 12, 12, 24, 12, 12, 12, 12, 12, 12, 12, 24, 12, 12, 12, 12, 12, 12, 12, 12, 12, 36, 12,
			36, 12, 12, 12, 36, 12, 12, 12, 12, 12, 36, 12, 36, 12, 12, 12, 36, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12
		};

		TOML_PURE_INLINE_GETTER
		constexpr bool error() const noexcept
		{
			return state == uint_least32_t{ 12u };
		}

		TOML_PURE_INLINE_GETTER
		constexpr bool has_code_point() const noexcept
		{
			return state == uint_least32_t{};
		}

		TOML_PURE_INLINE_GETTER
		constexpr bool needs_more_input() const noexcept
		{
			return !has_code_point() && !error();
		}

		constexpr void operator()(uint8_t byte) noexcept
		{
			TOML_ASSERT_ASSUME(!error());

			const auto type = state_table[byte];

			codepoint = static_cast<char32_t>(has_code_point() ? (uint_least32_t{ 255u } >> type) & byte
															   : (byte & uint_least32_t{ 63u })
																	 | (static_cast<uint_least32_t>(codepoint) << 6));

			state = state_table[state + uint_least32_t{ 256u } + type];
		}

		TOML_ALWAYS_INLINE
		constexpr void operator()(char c) noexcept
		{
			operator()(static_cast<uint8_t>(c));
		}

		TOML_ALWAYS_INLINE
		constexpr void reset() noexcept
		{
			state = {};
		}
	};

	TOML_PURE_GETTER
	TOML_ATTR(nonnull)
	bool is_ascii(const char* str, size_t len) noexcept;
}
TOML_IMPL_NAMESPACE_END;

#if TOML_GCC && TOML_GCC < 9
#pragma GCC pop_options
#endif

/// \endcond
#include "header_end.h"