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json.hpp
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/*
Copyright (c) 2023 SamGaaWaa
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
*/
#pragma once
#include <utility>
#include <concepts>
#include <optional>
#include <string_view>
#include <cstring>
#include <bit>
#include <cctype>
#include <cstring>
#include <iostream>
#include <format>
#include <cstdint>
#include <variant>
#include <any>
#include <vector>
#include <map>
#include <algorithm>
#include <charconv>
#include <string_view>
#include <cassert>
#include <expected>
#include <stdio.h>
#include <functional>
#include <memory>
namespace json {
enum struct parse_error_t : uint8_t {
error,
happy_ending,
unknown_string_character,
unknown_space,
unknown_ESC,
unknown_hex_character,
unknown_utf8_bytes,
unknown_number_character,
unknown_boolean_character,
unknown_null_character,
early_EOF,
read_file_error,
extra_content,
too_deep,
duplicate_key
};
enum struct serialize_error_t : uint8_t {
error,
unknown_utf8_bytes
};
constexpr const char* error_string(const parse_error_t err)noexcept {
switch (err) {
case parse_error_t::error:
return "Error.";
case parse_error_t::happy_ending:
return "Happy ending.";
case parse_error_t::unknown_string_character:
return "Unknown string character.";
case parse_error_t::unknown_space:
return "Unknown space character.";
case parse_error_t::unknown_ESC:
return "Unknown ESC.";
case parse_error_t::unknown_hex_character:
return "Unknown hex character.";
case parse_error_t::unknown_utf8_bytes:
return "Unknown utf8 bytes.";
case parse_error_t::unknown_number_character:
return "Unknown number character.";
case parse_error_t::unknown_boolean_character:
return "Unknown boolean character.";
case parse_error_t::unknown_null_character:
return "Unknown null character.";
case parse_error_t::early_EOF:
return "Early EOF.";
case parse_error_t::read_file_error:
return "Read file error.";
case parse_error_t::extra_content:
return "Extra content.";
case parse_error_t::too_deep:
return "Too deep.";
case parse_error_t::duplicate_key:
return "Duplicate key.";
default:
std::unreachable();
}
std::unreachable();
}
constexpr const char* error_string(const serialize_error_t err)noexcept {
switch (err) {
case serialize_error_t::error:
return "Error.";
case serialize_error_t::unknown_utf8_bytes:
return "Unknown utf8 bytes.";
default:
std::unreachable();
}
std::unreachable();
}
template<class P>
concept Parser = requires(P p, char c, const char* data, size_t size) {
{ p.on_null() }->std::same_as<std::optional<parse_error_t>>;
{ p.on_true() }->std::same_as<std::optional<parse_error_t>>;
{ p.on_false() }->std::same_as<std::optional<parse_error_t>>;
{ p.on_string(data, size) }->std::same_as<std::optional<parse_error_t>>;
{ p.on_string_begin() }->std::same_as<std::optional<parse_error_t>>;
{ p.on_string_end() }->std::same_as<std::optional<parse_error_t>>;
{ p.on_comma() }->std::same_as<std::optional<parse_error_t>>;
{ p.on_colon() }->std::same_as<std::optional<parse_error_t>>;
{ p.on_number(c) }->std::same_as<std::optional<parse_error_t>>;
{ p.on_number_begin(c) }->std::same_as<std::optional<parse_error_t>>;
{ p.on_number_end() }->std::same_as<std::optional<parse_error_t>>;
{ p.on_left_square_bracket() }->std::same_as<std::optional<parse_error_t>>;
{ p.on_right_square_bracket() }->std::same_as<std::optional<parse_error_t>>;
{ p.on_left_brace() }->std::same_as<std::optional<parse_error_t>>;
{ p.on_right_brace() }->std::same_as<std::optional<parse_error_t>>;
};
template<class B>
concept Builder = requires(B b, std::string str, std::string num, bool bb) {
{ b.on_document_begin() }->std::same_as<std::optional<parse_error_t>>;
{ b.on_document_end() }->std::same_as<std::optional<parse_error_t>>;
{ b.on_object_begin() }->std::same_as<std::optional<parse_error_t>>;
{ b.on_object_end() }->std::same_as<std::optional<parse_error_t>>;
{ b.on_array_begin() }->std::same_as<std::optional<parse_error_t>>;
{ b.on_array_end() }->std::same_as<std::optional<parse_error_t>>;
{ b.on_key(std::move(str)) }->std::same_as<std::optional<parse_error_t>>;
{ b.on_string(std::move(str)) }->std::same_as<std::optional<parse_error_t>>;
{ b.on_number(std::move(num)) }->std::same_as<std::optional<parse_error_t>>;
{ b.on_bool(bb) }->std::same_as<std::optional<parse_error_t>>;
{ b.on_null() }->std::same_as<std::optional<parse_error_t>>;
{ b.get() };
};
namespace detail {
template<Parser P>
struct lexer {
constexpr explicit lexer(P* p)noexcept :_parser{ p } {}
constexpr std::optional<parse_error_t> operator()(const char* data, const size_t size)noexcept {
const char* iter = data;
const char* const end = iter + size;
std::optional<parse_error_t> err;
bytes = 0;
while (iter < end) {
switch (_state) {
case state_t::normal:
{
iter = skip_space(iter, end);
if (iter == end) {
bytes += size;
return {};
}
const char c = *iter;
switch (c) {
case '{':
err = _parser->on_left_brace();
if (err) {
bytes += iter - data + 1;
return err;
}
++iter;
continue;
case '}':
err = _parser->on_right_brace();
if (err) {
bytes += iter - data + 1;
return err;
}
++iter;
continue;
case '[':
err = _parser->on_left_square_bracket();
if (err) {
bytes += iter - data + 1;
return err;
}
++iter;
continue;
case ']':
err = _parser->on_right_square_bracket();
if (err) {
bytes += iter - data + 1;
return err;
}
++iter;
continue;
case 'f':
_state = state_t::f;
++iter;
continue;
case 't':
_state = state_t::t;
++iter;
continue;
case 'n':
_state = state_t::n;
++iter;
continue;
case '-':
err = _parser->on_number_begin(c);
if (err) {
bytes += iter - data + 1;
return err;
}
_state = state_t::after_optional_negative;
++iter;
continue;
case '0':
err = _parser->on_number_begin(c);
if (err) {
bytes += iter - data + 1;
return err;
}
_state = state_t::after_zero;
++iter;
continue;
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
err = _parser->on_number_begin(c);
if (err) {
bytes += iter - data + 1;
return err;
}
_state = state_t::after_one_to_nine;
++iter;
continue;
case '\"':
err = _parser->on_string_begin();
if (err) {
bytes += iter - data + 1;
return err;
}
_state = state_t::after_quotation_mark;
++iter;
continue;
case ':':
err = _parser->on_colon();
if (err) {
bytes += iter - data + 1;
return err;
}
++iter;
continue;
case ',':
err = _parser->on_comma();
if (err) {
bytes += iter - data + 1;
return err;
}
++iter;
continue;
default:
{
bytes += iter - data + 1;
return parse_error_t::unknown_space;
}
}
}
// string
case state_t::after_quotation_mark:
case state_t::after_reverse_solidus:
case state_t::wait_4_hex:
case state_t::wait_3_hex:
case state_t::wait_2_hex:
case state_t::wait_1_hex:
case state_t::wait_low_reverse_solidus:
case state_t::wait_low_u:
case state_t::wait_low_4_hex:
case state_t::wait_low_3_hex:
case state_t::wait_low_2_hex:
case state_t::wait_low_1_hex:
case state_t::wait_3_utf8_bytes:
case state_t::wait_2_utf8_bytes:
case state_t::wait_1_utf8_bytes:
{
iter = _parse_string(iter, end, err);
if (err) {
bytes += iter - data;
return err;
}
continue;
}
// number
case state_t::after_optional_negative:
{
const char c = *iter;
switch (c) {
case '0':
_parser->on_number(c);
_state = state_t::after_zero;
++iter;
continue;
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
_parser->on_number(c);
_state = state_t::after_one_to_nine;
++iter;
continue;
default:
bytes += iter - data + 1;
return parse_error_t::unknown_number_character;
}
}
case state_t::after_point:
{
const char c = *iter;
switch (c) {
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
_parser->on_number(c);
_state = state_t::fractional_part;
++iter;
continue;
default:
bytes += iter - data + 1;
return parse_error_t::unknown_number_character;
}
}
case state_t::after_e:
{
const char c = *iter;
switch (c) {
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
_parser->on_number(c);
_state = state_t::parsing_exponent;
++iter;
continue;
case '+':
case '-':
_parser->on_number(c);
_state = state_t::after_exponent_sign;
++iter;
continue;
default:
bytes += iter - data + 1;
return parse_error_t::unknown_number_character;
}
}
case state_t::after_exponent_sign:
{
const char c = *iter;
switch (c) {
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
_parser->on_number(c);
_state = state_t::parsing_exponent;
++iter;
continue;
default:
bytes += iter - data + 1;
return parse_error_t::unknown_number_character;
}
}
// number acceptable state
case state_t::after_zero:
{
const char c = *iter;
switch (c) {
case '.':
_parser->on_number(c);
_state = state_t::after_point;
++iter;
continue;
case 'e':
case 'E':
_parser->on_number(c);
_state = state_t::after_e;
++iter;
continue;
default:
err = _parser->on_number_end();
if (err) {
bytes += iter - data + 1;
return err;
}
_state = state_t::normal;
continue;
}
}
case state_t::after_one_to_nine:
{
const char c = *iter;
switch (c) {
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
_parser->on_number(c);
_state = state_t::parsing_digital;
++iter;
continue;
case '.':
_parser->on_number(c);
_state = state_t::after_point;
++iter;
continue;
case 'e':
case 'E':
_parser->on_number(c);
_state = state_t::after_e;
++iter;
continue;
default:
err = _parser->on_number_end();
if (err) {
bytes += iter - data + 1;
return err;
}
_state = state_t::normal;
continue;
}
}
case state_t::parsing_digital:
{
const char c = *iter;
switch (c) {
case '.':
_parser->on_number(c);
_state = state_t::after_point;
++iter;
continue;
case 'e':
case 'E':
_parser->on_number(c);
_state = state_t::after_e;
++iter;
continue;
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
_parser->on_number(c);
++iter;
continue;
default:
err = _parser->on_number_end();
if (err) {
bytes += iter - data + 1;
return err;
}
_state = state_t::normal;
continue;
}
}
case state_t::parsing_exponent:
{
const char c = *iter;
switch (c) {
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
_parser->on_number(c);
++iter;
continue;
default:
err = _parser->on_number_end();
if (err) {
bytes += iter - data + 1;
return err;
}
_state = state_t::normal;
continue;
}
}
case state_t::fractional_part:
{
const char c = *iter;
switch (c) {
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
_parser->on_number(c);
++iter;
continue;
case 'e':
case 'E':
_parser->on_number(c);
_state = state_t::after_e;
++iter;
continue;
default:
err = _parser->on_number_end();
if (err) {
bytes += iter - data + 1;
return err;
}
_state = state_t::normal;
continue;
}
}
// false
case state_t::f:
{
if (*iter == 'a') {
_state = state_t::fa;
++iter;
continue;
}
else {
bytes += iter - data + 1;
return parse_error_t::unknown_boolean_character;
}
}
case state_t::fa:
{
if (*iter == 'l') {
_state = state_t::fal;
++iter;
continue;
}
else {
bytes += iter - data + 1;
return parse_error_t::unknown_boolean_character;
}
}
case state_t::fal:
{
if (*iter == 's') {
_state = state_t::fals;
++iter;
continue;
}
else {
bytes += iter - data + 1;
return parse_error_t::unknown_boolean_character;
}
}
case state_t::fals:
{
if (*iter == 'e') {
err = _parser->on_false();
if (err) {
bytes += iter - data + 1;
return err;
}
_state = state_t::normal;
++iter;
continue;
}
else {
bytes += iter - data + 1;
return parse_error_t::unknown_boolean_character;
}
}
//true
case state_t::t:
{
if (*iter == 'r') {
_state = state_t::tr;
++iter;
continue;
}
else {
bytes += iter - data + 1;
return parse_error_t::unknown_boolean_character;
}
}
case state_t::tr:
{
if (*iter == 'u') {
_state = state_t::tru;
++iter;
continue;
}
else {
bytes += iter - data + 1;
return parse_error_t::unknown_boolean_character;
}
}
case state_t::tru:
{
if (*iter == 'e') {
err = _parser->on_true();
if (err) {
bytes += iter - data + 1;
return err;
}
_state = state_t::normal;
++iter;
continue;
}
else {
bytes += iter - data + 1;
return parse_error_t::unknown_boolean_character;
}
}
//null
case state_t::n:
{
if (*iter == 'u') {
_state = state_t::nu;
++iter;
continue;
}
else {
bytes += iter - data + 1;
return parse_error_t::unknown_null_character;
}
}
case state_t::nu:
{
if (*iter == 'l') {
_state = state_t::nul;
++iter;
continue;
}
else {
bytes += iter - data + 1;
return parse_error_t::unknown_null_character;
}
}
case state_t::nul:
{
if (*iter == 'l') {
err = _parser->on_null();
if (err) {
bytes += iter - data + 1;
return err;
}
_state = state_t::normal;
++iter;
continue;
}
else {
bytes += iter - data + 1;
return parse_error_t::unknown_null_character;
}
}
default:
std::unreachable();
}
}
bytes += size;
return {};
}
static constexpr bool is_space(const char c)noexcept {
switch (c) {
case ' ':
case '\n':
case '\t':
case '\r':
case '\0':
return true;
default:
return false;
}
}
static constexpr const char* skip_space(const char* iter, const char* const end)noexcept {
while (iter != end and is_space(*iter)) {
++iter;
}
return iter;
}
static constexpr std::optional<uint32_t> hex_to_int(const char c)noexcept {
switch (c) {
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
return uint32_t(c - '0');
case 'a':
case 'b':
case 'c':
case 'd':
case 'e':
case 'f':
return uint32_t(c - 'a' + 10);
case 'A':
case 'B':
case 'C':
case 'D':
case 'E':
case 'F':
return uint32_t(c - 'A' + 10);
default:
return std::nullopt;
}
}
constexpr static std::string_view unicode_to_utf8(const uint32_t uc)noexcept {
static char buf[4];
size_t n = 0;
if (uc <= 0x7F) {
// 单字节 UTF-8 编码
n = 1;
buf[0] = static_cast<char>(uc);
}
else if (uc <= 0x7FF) {
// 双字节 UTF-8 编码
n = 2;
buf[0] = static_cast<char>(0xC0 | (uc >> 6));
buf[1] = static_cast<char>(0x80 | (uc & 0x3F));
}
else if (uc <= 0xFFFF) {
// 三字节 UTF-8 编码
n = 3;
buf[0] = static_cast<char>(0xE0 | (uc >> 12));
buf[1] = static_cast<char>(0x80 | ((uc >> 6) & 0x3F));
buf[2] = static_cast<char>(0x80 | (uc & 0x3F));
}
else if (uc <= 0x10FFFF) {
// 四字节 UTF-8 编码
n = 4;
buf[0] = static_cast<char>(0xF0 | (uc >> 18));
buf[1] = static_cast<char>(0x80 | ((uc >> 12) & 0x3F));
buf[2] = static_cast<char>(0x80 | ((uc >> 6) & 0x3F));
buf[3] = static_cast<char>(0x80 | (uc & 0x3F));
}
return { buf, n };
}
P* _parser;
enum struct state_t {
normal,
// string
after_quotation_mark,
after_reverse_solidus,
wait_4_hex,
wait_3_hex,
wait_2_hex,
wait_1_hex,
wait_low_reverse_solidus,
wait_low_u,
wait_low_4_hex,
wait_low_3_hex,
wait_low_2_hex,
wait_low_1_hex,
wait_3_utf8_bytes,
wait_2_utf8_bytes,
wait_1_utf8_bytes,
// number
after_optional_negative,
after_zero, //end
after_one_to_nine, //end
after_point,
parsing_digital, //end
after_e,
parsing_exponent, //end
after_exponent_sign,
fractional_part, //end
// false
f,
fa,
fal,
fals,
//true
t,
tr,
tru,
//null
n,
nu,
nul,
error
};
state_t _state = state_t::normal;
uint8_t _hex = 0;
size_t bytes = 0;
uint32_t unicode_high = 0;
uint32_t unicode_low = 0;
private:
const char* _parse_string(const char* const data, const char* const end, std::optional<parse_error_t>& err)noexcept {
const char* iter = data;
const char* start = data;
while (iter < end) {
switch (_state) {
case state_t::after_quotation_mark:
{
const char c = *iter;
switch (std::countl_one((uint8_t)c)) {
case 0:
{ //ASCII
if (std::iscntrl(c)) {
err = parse_error_t::unknown_string_character;
return iter + 1;
}
switch (c) {
case '\"':
if (start < iter) {
_parser->on_string(start, iter - start);
}
_parser->on_string_end();
_state = state_t::normal;
return iter + 1;
case '\\':
_parser->on_string(start, iter - start);
_state = state_t::after_reverse_solidus;
++iter;
continue;
default:
++iter;
continue;
}
}
case 1:
{
err = parse_error_t::unknown_string_character;
return iter + 1;
}
case 2:
_state = state_t::wait_1_utf8_bytes;
++iter;
continue;
case 3:
_state = state_t::wait_2_utf8_bytes;
++iter;
continue;
case 4:
_state = state_t::wait_3_utf8_bytes;
++iter;
continue;
default:
err = parse_error_t::unknown_string_character;
return iter + 1;
}
}
case state_t::after_reverse_solidus:
{
const char c = *iter;
switch (c) {
case '\"':
case '\\':
case '/':
_parser->on_string(&c, 1);
_state = state_t::after_quotation_mark;
start = ++iter;
continue;
case 'b':
_parser->on_string("\b", 1);
_state = state_t::after_quotation_mark;
start = ++iter;
continue;
case 'f':
_parser->on_string("\f", 1);
_state = state_t::after_quotation_mark;
start = ++iter;
continue;
case 'n':
_parser->on_string("\n", 1);
_state = state_t::after_quotation_mark;
start = ++iter;
continue;
case 'r':
_parser->on_string("\r", 1);
_state = state_t::after_quotation_mark;
start = ++iter;
continue;
case 't':
_parser->on_string("\t", 1);
_state = state_t::after_quotation_mark;
start = ++iter;
continue;
case 'u':
_state = state_t::wait_4_hex;
++iter;
continue;
default:
err = parse_error_t::unknown_ESC;
return iter + 1;
}
}
case state_t::wait_4_hex:
{
const char c = *iter;
if (auto op = hex_to_int(c); op) {
unicode_high |= ((*op) << 12);
_state = state_t::wait_3_hex;
++iter;
continue;
}
else {
err = parse_error_t::unknown_hex_character;
return iter + 1;
}
}
case state_t::wait_3_hex:
{
const char c = *iter;
if (auto op = hex_to_int(c); op) {
unicode_high |= ((*op) << 8);
_state = state_t::wait_2_hex;
++iter;
continue;