mirror of
https://github.com/danog/libtgvoip.git
synced 2024-11-30 04:39:03 +01:00
233 lines
9.1 KiB
C++
Executable File
233 lines
9.1 KiB
C++
Executable File
/* json11
|
|
*
|
|
* json11 is a tiny JSON library for C++11, providing JSON parsing and serialization.
|
|
*
|
|
* The core object provided by the library is json11::Json. A Json object represents any JSON
|
|
* value: null, bool, number (int or double), string (std::string), array (std::vector), or
|
|
* object (std::map).
|
|
*
|
|
* Json objects act like values: they can be assigned, copied, moved, compared for equality or
|
|
* order, etc. There are also helper methods Json::dump, to serialize a Json to a string, and
|
|
* Json::parse (static) to parse a std::string as a Json object.
|
|
*
|
|
* Internally, the various types of Json object are represented by the JsonValue class
|
|
* hierarchy.
|
|
*
|
|
* A note on numbers - JSON specifies the syntax of number formatting but not its semantics,
|
|
* so some JSON implementations distinguish between integers and floating-point numbers, while
|
|
* some don't. In json11, we choose the latter. Because some JSON implementations (namely
|
|
* Javascript itself) treat all numbers as the same type, distinguishing the two leads
|
|
* to JSON that will be *silently* changed by a round-trip through those implementations.
|
|
* Dangerous! To avoid that risk, json11 stores all numbers as double internally, but also
|
|
* provides integer helpers.
|
|
*
|
|
* Fortunately, double-precision IEEE754 ('double') can precisely store any integer in the
|
|
* range +/-2^53, which includes every 'int' on most systems. (Timestamps often use int64
|
|
* or long long to avoid the Y2038K problem; a double storing microseconds since some epoch
|
|
* will be exact for +/- 275 years.)
|
|
*/
|
|
|
|
/* Copyright (c) 2013 Dropbox, Inc.
|
|
*
|
|
* 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 <string>
|
|
#include <vector>
|
|
#include <map>
|
|
#include <memory>
|
|
#include <initializer_list>
|
|
|
|
#ifdef _MSC_VER
|
|
#if _MSC_VER <= 1800 // VS 2013
|
|
#ifndef noexcept
|
|
#define noexcept throw()
|
|
#endif
|
|
|
|
#ifndef snprintf
|
|
#define snprintf _snprintf_s
|
|
#endif
|
|
#endif
|
|
#endif
|
|
|
|
namespace json11 {
|
|
|
|
enum JsonParse {
|
|
STANDARD, COMMENTS
|
|
};
|
|
|
|
class JsonValue;
|
|
|
|
class Json final {
|
|
public:
|
|
// Types
|
|
enum Type {
|
|
NUL, NUMBER, BOOL, STRING, ARRAY, OBJECT
|
|
};
|
|
|
|
// Array and object typedefs
|
|
typedef std::vector<Json> array;
|
|
typedef std::map<std::string, Json> object;
|
|
|
|
// Constructors for the various types of JSON value.
|
|
Json() noexcept; // NUL
|
|
Json(std::nullptr_t) noexcept; // NUL
|
|
Json(double value); // NUMBER
|
|
Json(int value); // NUMBER
|
|
Json(bool value); // BOOL
|
|
Json(const std::string &value); // STRING
|
|
Json(std::string &&value); // STRING
|
|
Json(const char * value); // STRING
|
|
Json(const array &values); // ARRAY
|
|
Json(array &&values); // ARRAY
|
|
Json(const object &values); // OBJECT
|
|
Json(object &&values); // OBJECT
|
|
|
|
// Implicit constructor: anything with a to_json() function.
|
|
template <class T, class = decltype(&T::to_json)>
|
|
Json(const T & t) : Json(t.to_json()) {}
|
|
|
|
// Implicit constructor: map-like objects (std::map, std::unordered_map, etc)
|
|
template <class M, typename std::enable_if<
|
|
std::is_constructible<std::string, decltype(std::declval<M>().begin()->first)>::value
|
|
&& std::is_constructible<Json, decltype(std::declval<M>().begin()->second)>::value,
|
|
int>::type = 0>
|
|
Json(const M & m) : Json(object(m.begin(), m.end())) {}
|
|
|
|
// Implicit constructor: vector-like objects (std::list, std::vector, std::set, etc)
|
|
template <class V, typename std::enable_if<
|
|
std::is_constructible<Json, decltype(*std::declval<V>().begin())>::value,
|
|
int>::type = 0>
|
|
Json(const V & v) : Json(array(v.begin(), v.end())) {}
|
|
|
|
// This prevents Json(some_pointer) from accidentally producing a bool. Use
|
|
// Json(bool(some_pointer)) if that behavior is desired.
|
|
Json(void *) = delete;
|
|
|
|
// Accessors
|
|
Type type() const;
|
|
|
|
bool is_null() const { return type() == NUL; }
|
|
bool is_number() const { return type() == NUMBER; }
|
|
bool is_bool() const { return type() == BOOL; }
|
|
bool is_string() const { return type() == STRING; }
|
|
bool is_array() const { return type() == ARRAY; }
|
|
bool is_object() const { return type() == OBJECT; }
|
|
|
|
// Return the enclosed value if this is a number, 0 otherwise. Note that json11 does not
|
|
// distinguish between integer and non-integer numbers - number_value() and int_value()
|
|
// can both be applied to a NUMBER-typed object.
|
|
double number_value() const;
|
|
int int_value() const;
|
|
|
|
// Return the enclosed value if this is a boolean, false otherwise.
|
|
bool bool_value() const;
|
|
// Return the enclosed string if this is a string, "" otherwise.
|
|
const std::string &string_value() const;
|
|
// Return the enclosed std::vector if this is an array, or an empty vector otherwise.
|
|
const array &array_items() const;
|
|
// Return the enclosed std::map if this is an object, or an empty map otherwise.
|
|
const object &object_items() const;
|
|
|
|
// Return a reference to arr[i] if this is an array, Json() otherwise.
|
|
const Json & operator[](size_t i) const;
|
|
// Return a reference to obj[key] if this is an object, Json() otherwise.
|
|
const Json & operator[](const std::string &key) const;
|
|
|
|
// Serialize.
|
|
void dump(std::string &out) const;
|
|
std::string dump() const {
|
|
std::string out;
|
|
dump(out);
|
|
return out;
|
|
}
|
|
|
|
// Parse. If parse fails, return Json() and assign an error message to err.
|
|
static Json parse(const std::string & in,
|
|
std::string & err,
|
|
JsonParse strategy = JsonParse::STANDARD);
|
|
static Json parse(const char * in,
|
|
std::string & err,
|
|
JsonParse strategy = JsonParse::STANDARD) {
|
|
if (in) {
|
|
return parse(std::string(in), err, strategy);
|
|
} else {
|
|
err = "null input";
|
|
return nullptr;
|
|
}
|
|
}
|
|
// Parse multiple objects, concatenated or separated by whitespace
|
|
static std::vector<Json> parse_multi(
|
|
const std::string & in,
|
|
std::string::size_type & parser_stop_pos,
|
|
std::string & err,
|
|
JsonParse strategy = JsonParse::STANDARD);
|
|
|
|
static inline std::vector<Json> parse_multi(
|
|
const std::string & in,
|
|
std::string & err,
|
|
JsonParse strategy = JsonParse::STANDARD) {
|
|
std::string::size_type parser_stop_pos;
|
|
return parse_multi(in, parser_stop_pos, err, strategy);
|
|
}
|
|
|
|
bool operator== (const Json &rhs) const;
|
|
bool operator< (const Json &rhs) const;
|
|
bool operator!= (const Json &rhs) const { return !(*this == rhs); }
|
|
bool operator<= (const Json &rhs) const { return !(rhs < *this); }
|
|
bool operator> (const Json &rhs) const { return (rhs < *this); }
|
|
bool operator>= (const Json &rhs) const { return !(*this < rhs); }
|
|
|
|
/* has_shape(types, err)
|
|
*
|
|
* Return true if this is a JSON object and, for each item in types, has a field of
|
|
* the given type. If not, return false and set err to a descriptive message.
|
|
*/
|
|
typedef std::initializer_list<std::pair<std::string, Type>> shape;
|
|
bool has_shape(const shape & types, std::string & err) const;
|
|
|
|
private:
|
|
std::shared_ptr<JsonValue> m_ptr;
|
|
};
|
|
|
|
// Internal class hierarchy - JsonValue objects are not exposed to users of this API.
|
|
class JsonValue {
|
|
protected:
|
|
friend class Json;
|
|
friend class JsonInt;
|
|
friend class JsonDouble;
|
|
virtual Json::Type type() const = 0;
|
|
virtual bool equals(const JsonValue * other) const = 0;
|
|
virtual bool less(const JsonValue * other) const = 0;
|
|
virtual void dump(std::string &out) const = 0;
|
|
virtual double number_value() const;
|
|
virtual int int_value() const;
|
|
virtual bool bool_value() const;
|
|
virtual const std::string &string_value() const;
|
|
virtual const Json::array &array_items() const;
|
|
virtual const Json &operator[](size_t i) const;
|
|
virtual const Json::object &object_items() const;
|
|
virtual const Json &operator[](const std::string &key) const;
|
|
virtual ~JsonValue() {}
|
|
};
|
|
|
|
} // namespace json11
|