Crow/json.h

1230 lines
38 KiB
C++

#pragma once
//#define FLASKPP_JSON_NO_ERROR_CHECK
#include <string>
#include <unordered_map>
#include <iostream>
#include <algorithm>
#include <memory>
#include <boost/lexical_cast.hpp>
#include <boost/algorithm/string/predicate.hpp>
#include <boost/operators.hpp>
#ifdef __GNUG__
#define flask_json_likely(x) __builtin_expect(x, 1)
#define flask_json_unlikely(x) __builtin_expect(x, 0)
#else
#ifdef __clang__
#define flask_json_likely(x) __builtin_expect(x, 1)
#define flask_json_unlikely(x) __builtin_expect(x, 0)
#else
#define flask_json_likely(x) x
#define flask_json_unlikely(x) x
#endif
#endif
namespace flask
{
namespace json
{
std::string escape(const std::string& str)
{
// TODO
return str;
}
std::string unescape(const std::string& str)
{
// TODO
return str;
}
enum class type : char
{
Null,
False,
True,
Number,
String,
List,
Object,
};
class rvalue;
rvalue load(const char* data, size_t size);
namespace detail
{
struct r_string
: boost::less_than_comparable<r_string>,
boost::less_than_comparable<r_string, std::string>,
boost::equality_comparable<r_string>,
boost::equality_comparable<r_string, std::string>
{
r_string() {};
r_string(const char* s, uint32_t length, uint8_t has_escaping)
: s_(s), length_(length), has_escaping_(has_escaping)
{};
~r_string()
{
if (owned_)
delete[] s_;
}
r_string(const r_string& r)
{
*this = r;
}
r_string(r_string&& r)
{
*this = r;
}
r_string& operator = (r_string&& r)
{
s_ = r.s_;
length_ = r.length_;
has_escaping_ = r.has_escaping_;
owned_ = r.owned_;
return *this;
}
r_string& operator = (const r_string& r)
{
s_ = r.s_;
length_ = r.length_;
has_escaping_ = r.has_escaping_;
owned_ = 0;
return *this;
}
operator std::string () const
{
return unescape();
}
std::string unescape() const
{
// TODO
return std::string(begin(), end());
}
const char* begin() const { return s_; }
const char* end() const { return s_+length_; }
using iterator = const char*;
using const_iterator = const char*;
const char* s_;
uint32_t length_;
uint8_t has_escaping_;
uint8_t owned_{0};
friend std::ostream& operator << (std::ostream& os, const r_string& s)
{
os << (std::string)s;
return os;
}
private:
void force(const char* s, uint32_t length)
{
s_ = s;
length_ = length;
owned_ = 1;
}
friend rvalue flask::json::load(const char* data, size_t size);
};
bool operator < (const r_string& l, const r_string& r)
{
return boost::lexicographical_compare(l,r);
}
bool operator < (const r_string& l, const std::string& r)
{
return boost::lexicographical_compare(l,r);
}
bool operator > (const r_string& l, const std::string& r)
{
return boost::lexicographical_compare(r,l);
}
bool operator == (const r_string& l, const r_string& r)
{
return boost::equals(l,r);
}
bool operator == (const r_string& l, const std::string& r)
{
return boost::equals(l,r);
}
}
class rvalue
{
static const int error_bit = 4;
public:
rvalue() noexcept : option_{error_bit}
{}
rvalue(type t) noexcept
: lsize_{}, lremain_{}, t_{t}
{}
rvalue(type t, const char* s, const char* e) noexcept
: start_{s},
end_{e},
t_{t}
{}
rvalue(type t, const char* s, const char* e, uint8_t option) noexcept
: start_{s},
end_{e},
t_{t},
option_{option}
{}
rvalue(const rvalue& r)
: start_(r.start_),
end_(r.end_),
key_(r.key_),
t_(r.t_),
option_(r.option_)
{
copy_l(r);
}
rvalue(rvalue&& r) noexcept
{
*this = std::move(r);
}
rvalue& operator = (const rvalue& r)
{
start_ = r.start_;
end_ = r.end_;
key_ = r.key_;
copy_l(r);
t_ = r.t_;
option_ = r.option_;
return *this;
}
rvalue& operator = (rvalue&& r) noexcept
{
start_ = r.start_;
end_ = r.end_;
key_ = std::move(r.key_);
l_ = std::move(r.l_);
lsize_ = r.lsize_;
lremain_ = r.lremain_;
t_ = r.t_;
option_ = r.option_;
return *this;
}
explicit operator bool() const noexcept
{
return (option_ & error_bit) == 0;
}
explicit operator int64_t() const
{
return i();
}
explicit operator int() const
{
return i();
}
type t() const
{
#ifndef FLASKPP_JSON_NO_ERROR_CHECK
if (option_ & error_bit)
{
throw std::runtime_error("invalid json object");
}
#endif
return t_;
}
int64_t i() const
{
#ifndef FLASKPP_JSON_NO_ERROR_CHECK
if (t() != type::Number)
throw std::runtime_error("value is not number");
#endif
return boost::lexical_cast<int64_t>(start_, end_-start_);
}
double d() const
{
#ifndef FLASKPP_JSON_NO_ERROR_CHECK
if (t() != type::Number)
throw std::runtime_error("value is not number");
#endif
return boost::lexical_cast<double>(start_, end_-start_);
}
detail::r_string s() const
{
#ifndef FLASKPP_JSON_NO_ERROR_CHECK
if (t() != type::String)
throw std::runtime_error("value is not string");
#endif
return detail::r_string{start_, (uint32_t)(end_-start_), has_escaping()};
}
bool has(const char* str) const
{
return has(std::string(str));
}
bool has(const std::string& str) const
{
struct Pred
{
bool operator()(const rvalue& l, const rvalue& r) const
{
return l.key_ < r.key_;
};
bool operator()(const rvalue& l, const std::string& r) const
{
return l.key_ < r;
};
bool operator()(const std::string& l, const rvalue& r) const
{
return l < r.key_;
};
};
if (!is_cached())
{
std::sort(begin(), end(), Pred());
set_cached();
}
auto it = lower_bound(begin(), end(), str, Pred());
return it != end() && it->key_ == str;
}
rvalue* begin() const
{
#ifndef FLASKPP_JSON_NO_ERROR_CHECK
if (t() != type::Object && t() != type::List)
throw std::runtime_error("value is not a container");
#endif
return l_.get();
}
rvalue* end() const
{
#ifndef FLASKPP_JSON_NO_ERROR_CHECK
if (t() != type::Object && t() != type::List)
throw std::runtime_error("value is not a container");
#endif
return l_.get()+lsize_;
}
const detail::r_string& key() const
{
return key_;
}
size_t size() const
{
#ifndef FLASKPP_JSON_NO_ERROR_CHECK
if (t() != type::Object && t() != type::List)
throw std::runtime_error("value is not a container");
#endif
return lsize_;
}
const rvalue& operator[](int index) const
{
#ifndef FLASKPP_JSON_NO_ERROR_CHECK
if (t() != type::List)
throw std::runtime_error("value is not a list");
if (index >= (int)lsize_ || index < 0)
throw std::runtime_error("list out of bound");
#endif
return l_[index];
}
const rvalue& operator[](size_t index) const
{
#ifndef FLASKPP_JSON_NO_ERROR_CHECK
if (t() != type::List)
throw std::runtime_error("value is not a list");
if (index >= lsize_)
throw std::runtime_error("list out of bound");
#endif
return l_[index];
}
const rvalue& operator[](const char* str) const
{
return this->operator[](std::string(str));
}
const rvalue& operator[](const std::string& str) const
{
#ifndef FLASKPP_JSON_NO_ERROR_CHECK
if (t() != type::Object)
throw std::runtime_error("value is not an object");
#endif
struct Pred
{
bool operator()(const rvalue& l, const rvalue& r) const
{
return l.key_ < r.key_;
};
bool operator()(const rvalue& l, const std::string& r) const
{
return l.key_ < r;
};
bool operator()(const std::string& l, const rvalue& r) const
{
return l < r.key_;
};
};
if (!is_cached())
{
std::sort(begin(), end(), Pred());
set_cached();
}
auto it = lower_bound(begin(), end(), str, Pred());
if (it != end() && it->key_ == str)
return *it;
#ifndef FLASKPP_JSON_NO_ERROR_CHECK
throw std::runtime_error("cannot find key");
#else
static rvalue nullValue;
return nullValue;
#endif
}
void set_error()
{
option_|=error_bit;
}
bool error() const
{
return (option_&error_bit)!=0;
}
private:
bool has_escaping() const
{
return (option_&1)!=0;
}
bool is_cached() const
{
return (option_&2)!=0;
}
void set_cached() const
{
option_ |= 2;
}
void copy_l(const rvalue& r)
{
lsize_ = r.lsize_;
lremain_ = 0;
l_.reset(new rvalue[lsize_]);
std::copy(r.begin(), r.end(), begin());
}
void emplace_back(rvalue&& v)
{
if (!lremain_)
{
int new_size = lsize_ + lsize_;
if (new_size - lsize_ > 60000)
new_size = lsize_ + 60000;
if (new_size < 4)
new_size = 4;
rvalue* p = new rvalue[new_size];
rvalue* p2 = p;
for(auto& x : *this)
*p2++ = std::move(x);
l_.reset(p);
lremain_ = new_size - lsize_;
}
l_[lsize_++] = std::move(v);
lremain_ --;
}
const char* start_;
const char* end_;
detail::r_string key_;
std::unique_ptr<rvalue[]> l_;
uint32_t lsize_;
uint16_t lremain_;
type t_;
mutable uint8_t option_{0};
friend rvalue load_nocopy_internal(const char* data, size_t size);
friend rvalue load(const char* data, size_t size);
friend std::ostream& operator <<(std::ostream& os, const rvalue& r)
{
switch(r.t_)
{
case type::Null: os << "null"; break;
case type::False: os << "false"; break;
case type::True: os << "true"; break;
case type::Number: os << r.d(); break;
case type::String: os << '"' << r.s() << '"'; break;
case type::List:
{
os << '[';
bool first = true;
for(auto& x : r)
{
if (!first)
os << ',';
first = false;
os << x;
}
os << ']';
}
break;
case type::Object:
{
os << '{';
bool first = true;
for(auto& x : r)
{
if (!first)
os << ',';
os << '"' << escape(r.key_) << '"';
first = false;
os << x;
}
os << '}';
}
break;
}
return os;
}
};
bool operator == (const rvalue& l, const std::string& r)
{
return l.s() == r;
}
bool operator == (const std::string& l, const rvalue& r)
{
return l == r.s();
}
bool operator != (const rvalue& l, const std::string& r)
{
return l.s() != r;
}
bool operator != (const std::string& l, const rvalue& r)
{
return l != r.s();
}
bool operator == (const rvalue& l, double r)
{
return l.d() == r;
}
bool operator == (double l, const rvalue& r)
{
return l == r.d();
}
bool operator != (const rvalue& l, double r)
{
return l.d() != r;
}
bool operator != (double l, const rvalue& r)
{
return l != r.d();
}
//inline rvalue decode(const std::string& s)
//{
//}
inline rvalue load_nocopy_internal(const char* data, size_t size)
{
//static const char* escaped = "\"\\/\b\f\n\r\t";
struct Parser
{
Parser(const char* data, size_t size)
: data(data)
{
}
bool consume(char c)
{
if (flask_json_unlikely(*data != c))
return false;
data++;
return true;
}
void ws_skip()
{
while(*data == ' ' || *data == '\t' || *data == '\r' || *data == '\n') ++data;
};
rvalue decode_string()
{
if (flask_json_unlikely(!consume('"')))
return {};
const char* start = data;
uint8_t has_escaping = 0;
while(1)
{
if (flask_json_likely(*data != '"' && *data != '\\' && *data != '\0'))
{
data ++;
}
else if (*data == '"')
{
data++;
return {type::String, start, data-1, has_escaping};
}
else if (*data == '\\')
{
has_escaping = 1;
// TODO
data++;
switch(*data)
{
case 'u':
data += 4;
// TODO
break;
case '"':
case '\\':
case '/':
case 'b':
case 'f':
case 'n':
case 'r':
case 't':
data ++;
break;
default:
return {};
}
}
else
return {};
}
return {};
}
rvalue decode_list()
{
rvalue ret(type::List);
if (flask_json_unlikely(!consume('[')))
{
ret.set_error();
return ret;
}
ws_skip();
if (flask_json_unlikely(*data == ']'))
{
data++;
return ret;
}
while(1)
{
auto v = decode_value();
if (flask_json_unlikely(!v))
{
ret.set_error();
break;
}
ws_skip();
ret.emplace_back(std::move(v));
if (*data == ']')
{
data++;
break;
}
if (flask_json_unlikely(!consume(',')))
{
ret.set_error();
break;
}
ws_skip();
}
return ret;
}
rvalue decode_number()
{
const char* start = data;
enum NumberParsingState
{
Minus,
AfterMinus,
ZeroFirst,
Digits,
DigitsAfterPoints,
E,
DigitsAfterE,
Invalid,
} state{Minus};
while(flask_json_likely(state != Invalid))
{
switch(*data)
{
case '0':
state = (NumberParsingState)"\2\2\7\3\4\6\6"[state];
/*if (state == NumberParsingState::Minus || state == NumberParsingState::AfterMinus)
{
state = NumberParsingState::ZeroFirst;
}
else if (state == NumberParsingState::Digits ||
state == NumberParsingState::DigitsAfterE ||
state == NumberParsingState::DigitsAfterPoints)
{
// ok; pass
}
else if (state == NumberParsingState::E)
{
state = NumberParsingState::DigitsAfterE;
}
else
return {};*/
break;
case '1': case '2': case '3':
case '4': case '5': case '6':
case '7': case '8': case '9':
state = (NumberParsingState)"\3\3\7\3\4\6\6"[state];
while(*(data+1) >= '0' && *(data+1) <= '9') data++;
/*if (state == NumberParsingState::Minus || state == NumberParsingState::AfterMinus)
{
state = NumberParsingState::Digits;
}
else if (state == NumberParsingState::Digits ||
state == NumberParsingState::DigitsAfterE ||
state == NumberParsingState::DigitsAfterPoints)
{
// ok; pass
}
else if (state == NumberParsingState::E)
{
state = NumberParsingState::DigitsAfterE;
}
else
return {};*/
break;
case '.':
state = (NumberParsingState)"\7\7\7\4\7\7\7"[state];
/*
if (state == NumberParsingState::Digits)
{
state = NumberParsingState::DigitsAfterPoints;
}
else
return {};
*/
break;
case '-':
state = (NumberParsingState)"\1\7\7\7\7\6\7"[state];
/*if (state == NumberParsingState::Minus)
{
state = NumberParsingState::AfterMinus;
}
else if (state == NumberParsingState::E)
{
state = NumberParsingState::DigitsAfterE;
}
else
return {};*/
break;
case '+':
state = (NumberParsingState)"\7\7\7\7\7\6\7"[state];
/*if (state == NumberParsingState::E)
{
state = NumberParsingState::DigitsAfterE;
}
else
return {};*/
break;
case 'e': case 'E':
state = (NumberParsingState)"\7\7\7\5\5\7\7"[state];
/*if (state == NumberParsingState::Digits ||
state == NumberParsingState::DigitsAfterPoints)
{
state = NumberParsingState::E;
}
else
return {};*/
break;
default:
if (flask_json_likely(state == NumberParsingState::ZeroFirst ||
state == NumberParsingState::Digits ||
state == NumberParsingState::DigitsAfterPoints ||
state == NumberParsingState::DigitsAfterE))
return {type::Number, start, data};
else
return {};
}
data++;
}
return {};
}
rvalue decode_value()
{
switch(*data)
{
case '[':
return decode_list();
case '{':
return decode_object();
case '"':
return decode_string();
case 't':
if (//e-data >= 4 &&
data[1] == 'r' &&
data[2] == 'u' &&
data[3] == 'e')
{
data += 4;
return {type::True};
}
else
return {};
case 'f':
if (//e-data >= 5 &&
data[1] == 'a' &&
data[2] == 'l' &&
data[3] == 's' &&
data[4] == 'e')
{
data += 5;
return {type::False};
}
else
return {};
case 'n':
if (//e-data >= 4 &&
data[1] == 'u' &&
data[2] == 'l' &&
data[3] == 'l')
{
data += 4;
return {type::Null};
}
else
return {};
//case '1': case '2': case '3':
//case '4': case '5': case '6':
//case '7': case '8': case '9':
//case '0': case '-':
default:
return decode_number();
}
return {};
}
rvalue decode_object()
{
rvalue ret(type::Object);
if (flask_json_unlikely(!consume('{')))
{
ret.set_error();
return ret;
}
ws_skip();
if (flask_json_unlikely(*data == '}'))
{
data++;
return ret;
}
while(1)
{
auto t = decode_string();
if (flask_json_unlikely(!t))
{
ret.set_error();
break;
}
ws_skip();
if (flask_json_unlikely(!consume(':')))
{
ret.set_error();
break;
}
// TODO caching key to speed up (flyweight?)
auto key = t.s();
ws_skip();
auto v = decode_value();
if (flask_json_unlikely(!v))
{
ret.set_error();
break;
}
ws_skip();
v.key_ = std::move(key);
ret.emplace_back(std::move(v));
if (flask_json_unlikely(*data == '}'))
{
data++;
break;
}
if (flask_json_unlikely(!consume(',')))
{
ret.set_error();
break;
}
ws_skip();
}
return ret;
}
rvalue parse()
{
ws_skip();
auto ret = decode_value(); // or decode object?
ws_skip();
if (ret && *data != '\0')
ret.set_error();
return ret;
}
const char* data;
};
return Parser(data, size).parse();
}
inline rvalue load(const char* data, size_t size)
{
char* s = new char[size+1];
memcpy(s, data, size);
s[size] = 0;
auto ret = load_nocopy_internal(s, size);
if (ret)
ret.key_.force(s, size);
else
delete[] s;
return ret;
}
inline rvalue load(const char* data)
{
return load(data, strlen(data));
}
inline rvalue load(const std::string& str)
{
return load(str.data(), str.size());
}
class wvalue
{
public:
type t() { return t_; }
private:
type t_{type::Null};
double d;
std::string s;
std::unique_ptr<std::vector<wvalue>> l;
std::unique_ptr<std::unordered_map<std::string, wvalue>> o;
public:
wvalue() {}
wvalue(wvalue&& r)
{
*this = std::move(r);
}
wvalue& operator = (wvalue&& r)
{
t_ = r.t_;
d = r.d;
s = std::move(r.s);
l = std::move(r.l);
o = std::move(r.o);
return *this;
}
void clear()
{
t_ = type::Null;
l.reset();
o.reset();
}
void reset()
{
t_ = type::Null;
l.reset();
o.reset();
}
wvalue& operator = (std::nullptr_t)
{
reset();
return *this;
}
wvalue& operator = (bool value)
{
reset();
if (value)
t_ = type::True;
else
t_ = type::False;
return *this;
}
wvalue& operator = (double value)
{
reset();
t_ = type::Number;
d = value;
return *this;
}
wvalue& operator = (uint16_t value)
{
reset();
t_ = type::Number;
d = (double)value;
return *this;
}
wvalue& operator = (int16_t value)
{
reset();
t_ = type::Number;
d = (double)value;
return *this;
}
wvalue& operator = (uint32_t value)
{
reset();
t_ = type::Number;
d = (double)value;
return *this;
}
wvalue& operator = (int32_t value)
{
reset();
t_ = type::Number;
d = (double)value;
return *this;
}
wvalue& operator = (uint64_t value)
{
reset();
t_ = type::Number;
d = (double)value;
return *this;
}
wvalue& operator = (int64_t value)
{
reset();
t_ = type::Number;
d = (double)value;
return *this;
}
wvalue& operator=(const char* str)
{
reset();
t_ = type::String;
s = str;
return *this;
}
wvalue& operator=(const std::string& str)
{
reset();
t_ = type::String;
s = str;
return *this;
}
template <typename T>
wvalue& operator[](const std::vector<T>& v)
{
if (t_ != type::List)
reset();
t_ = type::List;
if (!l)
l = std::move(std::unique_ptr<std::vector<wvalue>>(new std::vector<wvalue>{}));
l->clear();
l->resize(v.size());
size_t idx = 0;
for(auto& x:v)
{
(*l)[idx++] = x;
}
return *this;
}
wvalue& operator[](unsigned index)
{
if (t_ != type::List)
reset();
t_ = type::List;
if (!l)
l = std::move(std::unique_ptr<std::vector<wvalue>>(new std::vector<wvalue>{}));
if (l->size() < index+1)
l->resize(index+1);
return (*l)[index];
}
wvalue& operator[](const std::string& str)
{
if (t_ != type::Object)
reset();
t_ = type::Object;
if (!o)
o = std::move(
std::unique_ptr<
std::unordered_map<std::string, wvalue>
>(
new std::unordered_map<std::string, wvalue>{}));
return (*o)[str];
}
size_t estimate_length() const
{
switch(t_)
{
case type::Null: return 4;
case type::False: return 5;
case type::True: return 4;
case type::Number: return 30;
case type::String: return 2+s.size()+s.size()/2;
case type::List:
{
size_t sum{};
if (l)
{
for(auto& x:*l)
{
sum += 1;
sum += x.estimate_length();
}
}
return sum+2;
}
case type::Object:
{
size_t sum{};
if (o)
{
for(auto& kv:*o)
{
sum += 2;
sum += 2+kv.first.size()+kv.first.size()/2;
sum += kv.second.estimate_length();
}
}
return sum+2;
}
}
return 1;
}
friend void dump_internal(const wvalue& v, std::string& out);
friend std::string dump(const wvalue& v);
};
void dump_string(const std::string& str, std::string& out)
{
// TODO escaping
out.push_back('"');
out += str;
out.push_back('"');
}
void dump_internal(const wvalue& v, std::string& out)
{
switch(v.t_)
{
case type::Null: out += "null"; break;
case type::False: out += "false"; break;
case type::True: out += "true"; break;
case type::Number: out += boost::lexical_cast<std::string>(v.d); break;
case type::String: dump_string(v.s, out); break;
case type::List:
{
out.push_back('[');
if (v.l)
{
bool first = true;
for(auto& x:*v.l)
{
if (!first)
{
out.push_back(',');
}
first = false;
dump_internal(x, out);
}
}
out.push_back(']');
}
break;
case type::Object:
{
out.push_back('{');
if (v.o)
{
bool first = true;
for(auto& kv:*v.o)
{
if (!first)
{
out.push_back(',');
}
first = false;
dump_string(kv.first, out);
out.push_back(':');
dump_internal(kv.second, out);
}
}
out.push_back('}');
}
break;
}
}
std::string dump(const wvalue& v)
{
std::string ret;
ret.reserve(v.estimate_length());
dump_internal(v, ret);
return ret;
}
//std::vector<boost::asio::const_buffer> dump_ref(wvalue& v)
//{
//}
}
}
#undef flask_json_likely
#undef flask_json_unlikely