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json.hpp
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1#ifndef LIBFILEZILLA_JSON_HEADER
2#define LIBFILEZILLA_JSON_HEADER
3
7#include "string.hpp"
8
9#include <limits.h>
10#include <map>
11#include <optional>
12#include <type_traits>
13#include <variant>
14
15namespace fz {
16
18enum class json_type {
19 none,
22 array,
23 string,
24 number,
25 boolean
26};
27
28class buffer;
29
32class FZ_PUBLIC_SYMBOL json final
33{
34public:
35 json() noexcept = default;
36 json(json const&) = default;
37 json(json &&) noexcept = default;
38
40 explicit json(json_type t);
41
42 json_type type() const {
43 return static_cast<json_type>(value_.index());
44 }
45
47 std::string string_value() const;
48
50 std::wstring wstring_value() const {
52 }
53
54
56 template<typename T, std::enable_if_t<std::is_integral_v<typename std::decay_t<T>>, int> = 0>
57 T number_value(T errorval = {}) const {
58 auto v = number_value_o<T>();
59 if (v) {
60 return *v;
61 }
62 return errorval;
63 }
64
65 template<typename T, std::enable_if_t<std::is_integral_v<typename std::decay_t<T>>, int> = 0>
66 std::optional<T> number_value_o() const {
67 bool constexpr is_signed = std::is_signed_v<typename std::decay_t<T>>;
68 if constexpr (is_signed) {
69 std::optional<int64_t> tmp = number_value_integer_s();
70 if (tmp) {
71 if (tmp >= std::numeric_limits<T>::min() && tmp <= std::numeric_limits<T>::max()) {
72 return static_cast<T>(*tmp);
73 }
74 }
75 }
76 else {
77 std::optional<uint64_t> tmp = number_value_integer_u();
78 if (tmp) {
79 if (tmp <= std::numeric_limits<T>::max()) {
80 return static_cast<T>(*tmp);
81 }
82 }
83 }
84
85 return {};
86 }
87
89 template<typename T, std::enable_if_t<std::is_floating_point_v<typename std::decay_t<T>>, int> = 0>
90 T number_value() const {
91 return static_cast<T>(number_value_double());
92 }
93
95 bool bool_value() const;
96
98 void erase(std::string const& name);
99
101 json const& operator[](std::string const& name) const;
102
109 json& operator[](std::string const& name);
110
112 json const& operator[](size_t i) const;
113
120 json& operator[](size_t i);
121
123 size_t children() const;
124
126 template<typename Bool, std::enable_if_t<std::is_same_v<bool, typename std::decay_t<Bool>>, int> = 0>
127 json& operator=(Bool b) {
128 value_ = b;
129 return *this;
130 }
131
133 template<typename T, std::enable_if_t<std::is_integral_v<T> && !std::is_same_v<bool, typename std::decay_t<T>>, int> = 0>
134 json& operator=(T n) {
135 value_.emplace<std::size_t(json_type::number)>(fz::to_string(n));
136 return *this;
137 }
138
143 json& operator=(std::string_view const& v);
144
146 json& operator=(std::wstring_view const& v) {
147 return *this = to_utf8(v);
148 }
149
150 json& operator=(json const&);
151 json& operator=(json &&) noexcept;
152
153 explicit operator bool() const { return type() != json_type::none; }
154
155 bool has_non_null_value() const {
156 return type() != fz::json_type::none && type() != fz::json_type::null;
157 }
158
159 bool is_null() const { return type() == fz::json_type::null; }
160 bool is_object() const { return type() == fz::json_type::object; }
161 bool is_array() const { return type() == fz::json_type::array; }
162 bool is_number() const { return type() == fz::json_type::number; }
163 bool is_boolean() const { return type() == fz::json_type::boolean; }
164
170 std::string to_string(bool pretty = false, size_t depth = 0) const;
171
179 void to_string(std::string & ret, bool pretty = false, size_t depth = 0) const;
180
185 static json parse(std::string_view const& v, size_t max_depth = 20);
186 static json parse(fz::buffer const& b, size_t max_depth = 20);
187
188 void clear();
189
190private:
191 void to_string_impl(std::string & ret, bool pretty = false, size_t depth = 0) const;
192
193 std::optional<int64_t> number_value_integer_s() const;
194 std::optional<uint64_t> number_value_integer_u() const;
195 double number_value_double() const;
196
197 bool FZ_PRIVATE_SYMBOL check_type(json_type t);
198 void FZ_PRIVATE_SYMBOL set_type(json_type t);
199
200 static json FZ_PRIVATE_SYMBOL parse(char const*& p, char const* end, size_t max_depth);
201
202 typedef std::variant<
203 std::monostate, // json_type::none
204 std::nullptr_t, // json_type::null
205 std::map<std::string, json, std::less<>>, // json_type::object
206 std::vector<json>, // json_type::array
207 std::string, // json_type::string,
208 std::string, // json_type::number,
209 bool // json_type::boolean
210 > value_type;
211 value_type value_;
212};
213
214template <bool isconst>
215struct json_array_iterator final {
216 using json_ref_t = std::conditional_t<isconst, json const&, json &>;
217
218 struct sentinel final {};
219
220 json_array_iterator(json_ref_t j)
221 // 0 if it's an array, -1 otherwise
222 : idx_((j.type() == json_type::array)-1)
223 , json_(j)
224 {}
225
226 json_array_iterator & operator++()
227 {
228 ++idx_;
229
230 return *this;
231 }
232
233 json_ref_t operator*() const
234 {
235 return json_[idx_];
236 }
237
238 bool operator!=(json_array_iterator::sentinel const&) const
239 {
240 return idx_ < json_.children();
241 }
242
243private:
244 std::size_t idx_;
245 json_ref_t json_;
246};
247
248inline json_array_iterator<false> begin(json &j) { return {j}; }
249inline json_array_iterator<false>::sentinel end(json &) { return {}; }
250
251inline json_array_iterator<true> begin(json const& j) { return {j}; }
252inline json_array_iterator<true>::sentinel end(json const&) { return {}; }
253
254}
255
256#endif
The buffer class is a simple buffer where data can be appended at the end and consumed at the front....
Definition buffer.hpp:27
json parser/builder
Definition json.hpp:33
static json parse(std::string_view const &v, size_t max_depth=20)
Parses JSON structure from input.
json & operator=(T n)
Sets type to number and assigns value.
Definition json.hpp:134
json & operator=(std::string_view const &v)
Sets type to string and assigns value.
std::string to_string(bool pretty=false, size_t depth=0) const
Serializes JSON structure.
json & operator[](size_t i)
Returns reference to the child value with the given index.
std::string string_value() const
Returns string, number and boolean values as string.
json const & operator[](std::string const &name) const
If object, get the value with the given name. Returns none if not object or name doesn't exist.
json & operator=(std::wstring_view const &v)
Sets type to string and assigns value.
Definition json.hpp:146
void erase(std::string const &name)
If object value, deletes child value with given name.
json & operator=(Bool b)
Sets type to boolean and assigns value.
Definition json.hpp:127
size_t children() const
For arrays and objects, returns the number of elements.
T number_value(T errorval={}) const
Returns number and string values as the passed integer type.
Definition json.hpp:57
void to_string(std::string &ret, bool pretty=false, size_t depth=0) const
Serializes JSON structure.
json & operator[](std::string const &name)
Returns reference to the child value with the given name.
T number_value() const
Returns number and string values as the passed floating point type.
Definition json.hpp:90
std::wstring wstring_value() const
Returns string, number and boolean values as wstring.
Definition json.hpp:50
json(json_type t)
Explicitly creates a value of a specific type, mainly needed for null objects.
bool bool_value() const
Returns boolean and string values as bool.
json const & operator[](size_t i) const
If array, get the value with the given index. Returns none if not array or index doesn't exist.
type
Definition logger.hpp:16
The namespace used by libfilezilla.
Definition apply.hpp:17
std::wstring to_wstring_from_utf8(std::string_view const &in)
Converts from std::string in UTF-8 into std::wstring.
std::string to_utf8(std::string_view const &in)
Converts from std::string in native encoding into std::string in UTF-8.
std::string to_string(std::wstring_view const &in)
Converts from std::wstring into std::string in system encoding.
json_type
Types of JSON values.
Definition json.hpp:18
@ null
Not a JSON value.
Definition json.hpp:20
@ object
The explicit null value.
Definition json.hpp:21
String types and assorted functions.
Definition json.hpp:218
Definition json.hpp:215