1 #pragma once
2 
3 #include <exception> // exception
4 #include <stdexcept> // runtime_error
5 #include <string> // to_string
6 
7 #include <nlohmann/detail/input/position_t.hpp>
8 #include <nlohmann/detail/macro_scope.hpp>
9 
10 namespace nlohmann
11 {
12 namespace detail
13 {
14 ////////////////
15 // exceptions //
16 ////////////////
17 
18 /*!
19 @brief general exception of the @ref basic_json class
20 
21 This class is an extension of `std::exception` objects with a member @a id for
22 exception ids. It is used as the base class for all exceptions thrown by the
23 @ref basic_json class. This class can hence be used as "wildcard" to catch
24 exceptions.
25 
26 Subclasses:
27 - @ref parse_error for exceptions indicating a parse error
28 - @ref invalid_iterator for exceptions indicating errors with iterators
29 - @ref type_error for exceptions indicating executing a member function with
30                   a wrong type
31 - @ref out_of_range for exceptions indicating access out of the defined range
32 - @ref other_error for exceptions indicating other library errors
33 
34 @internal
35 @note To have nothrow-copy-constructible exceptions, we internally use
36       `std::runtime_error` which can cope with arbitrary-length error messages.
37       Intermediate strings are built with static functions and then passed to
38       the actual constructor.
39 @endinternal
40 
41 @liveexample{The following code shows how arbitrary library exceptions can be
42 caught.,exception}
43 
44 @since version 3.0.0
45 */
46 class exception : public std::exception
47 {
48   public:
49     /// returns the explanatory string
50     JSON_HEDLEY_RETURNS_NON_NULL
what() const51     const char* what() const noexcept override
52     {
53         return m.what();
54     }
55 
56     /// the id of the exception
57     const int id;
58 
59   protected:
60     JSON_HEDLEY_NON_NULL(3)
exception(int id_,const char * what_arg)61     exception(int id_, const char* what_arg) : id(id_), m(what_arg) {}
62 
name(const std::string & ename,int id_)63     static std::string name(const std::string& ename, int id_)
64     {
65         return "[json.exception." + ename + "." + std::to_string(id_) + "] ";
66     }
67 
68   private:
69     /// an exception object as storage for error messages
70     std::runtime_error m;
71 };
72 
73 /*!
74 @brief exception indicating a parse error
75 
76 This exception is thrown by the library when a parse error occurs. Parse errors
77 can occur during the deserialization of JSON text, CBOR, MessagePack, as well
78 as when using JSON Patch.
79 
80 Member @a byte holds the byte index of the last read character in the input
81 file.
82 
83 Exceptions have ids 1xx.
84 
85 name / id                      | example message | description
86 ------------------------------ | --------------- | -------------------------
87 json.exception.parse_error.101 | parse error at 2: unexpected end of input; expected string literal | This error indicates a syntax error while deserializing a JSON text. The error message describes that an unexpected token (character) was encountered, and the member @a byte indicates the error position.
88 json.exception.parse_error.102 | parse error at 14: missing or wrong low surrogate | JSON uses the `\uxxxx` format to describe Unicode characters. Code points above above 0xFFFF are split into two `\uxxxx` entries ("surrogate pairs"). This error indicates that the surrogate pair is incomplete or contains an invalid code point.
89 json.exception.parse_error.103 | parse error: code points above 0x10FFFF are invalid | Unicode supports code points up to 0x10FFFF. Code points above 0x10FFFF are invalid.
90 json.exception.parse_error.104 | parse error: JSON patch must be an array of objects | [RFC 6902](https://tools.ietf.org/html/rfc6902) requires a JSON Patch document to be a JSON document that represents an array of objects.
91 json.exception.parse_error.105 | parse error: operation must have string member 'op' | An operation of a JSON Patch document must contain exactly one "op" member, whose value indicates the operation to perform. Its value must be one of "add", "remove", "replace", "move", "copy", or "test"; other values are errors.
92 json.exception.parse_error.106 | parse error: array index '01' must not begin with '0' | An array index in a JSON Pointer ([RFC 6901](https://tools.ietf.org/html/rfc6901)) may be `0` or any number without a leading `0`.
93 json.exception.parse_error.107 | parse error: JSON pointer must be empty or begin with '/' - was: 'foo' | A JSON Pointer must be a Unicode string containing a sequence of zero or more reference tokens, each prefixed by a `/` character.
94 json.exception.parse_error.108 | parse error: escape character '~' must be followed with '0' or '1' | In a JSON Pointer, only `~0` and `~1` are valid escape sequences.
95 json.exception.parse_error.109 | parse error: array index 'one' is not a number | A JSON Pointer array index must be a number.
96 json.exception.parse_error.110 | parse error at 1: cannot read 2 bytes from vector | When parsing CBOR or MessagePack, the byte vector ends before the complete value has been read.
97 json.exception.parse_error.112 | parse error at 1: error reading CBOR; last byte: 0xF8 | Not all types of CBOR or MessagePack are supported. This exception occurs if an unsupported byte was read.
98 json.exception.parse_error.113 | parse error at 2: expected a CBOR string; last byte: 0x98 | While parsing a map key, a value that is not a string has been read.
99 json.exception.parse_error.114 | parse error: Unsupported BSON record type 0x0F | The parsing of the corresponding BSON record type is not implemented (yet).
100 json.exception.parse_error.115 | parse error at byte 5: syntax error while parsing UBJSON high-precision number: invalid number text: 1A | A UBJSON high-precision number could not be parsed.
101 
102 @note For an input with n bytes, 1 is the index of the first character and n+1
103       is the index of the terminating null byte or the end of file. This also
104       holds true when reading a byte vector (CBOR or MessagePack).
105 
106 @liveexample{The following code shows how a `parse_error` exception can be
107 caught.,parse_error}
108 
109 @sa - @ref exception for the base class of the library exceptions
110 @sa - @ref invalid_iterator for exceptions indicating errors with iterators
111 @sa - @ref type_error for exceptions indicating executing a member function with
112                     a wrong type
113 @sa - @ref out_of_range for exceptions indicating access out of the defined range
114 @sa - @ref other_error for exceptions indicating other library errors
115 
116 @since version 3.0.0
117 */
118 class parse_error : public exception
119 {
120   public:
121     /*!
122     @brief create a parse error exception
123     @param[in] id_       the id of the exception
124     @param[in] pos       the position where the error occurred (or with
125                          chars_read_total=0 if the position cannot be
126                          determined)
127     @param[in] what_arg  the explanatory string
128     @return parse_error object
129     */
create(int id_,const position_t & pos,const std::string & what_arg)130     static parse_error create(int id_, const position_t& pos, const std::string& what_arg)
131     {
132         std::string w = exception::name("parse_error", id_) + "parse error" +
133                         position_string(pos) + ": " + what_arg;
134         return parse_error(id_, pos.chars_read_total, w.c_str());
135     }
136 
create(int id_,std::size_t byte_,const std::string & what_arg)137     static parse_error create(int id_, std::size_t byte_, const std::string& what_arg)
138     {
139         std::string w = exception::name("parse_error", id_) + "parse error" +
140                         (byte_ != 0 ? (" at byte " + std::to_string(byte_)) : "") +
141                         ": " + what_arg;
142         return parse_error(id_, byte_, w.c_str());
143     }
144 
145     /*!
146     @brief byte index of the parse error
147 
148     The byte index of the last read character in the input file.
149 
150     @note For an input with n bytes, 1 is the index of the first character and
151           n+1 is the index of the terminating null byte or the end of file.
152           This also holds true when reading a byte vector (CBOR or MessagePack).
153     */
154     const std::size_t byte;
155 
156   private:
parse_error(int id_,std::size_t byte_,const char * what_arg)157     parse_error(int id_, std::size_t byte_, const char* what_arg)
158         : exception(id_, what_arg), byte(byte_) {}
159 
position_string(const position_t & pos)160     static std::string position_string(const position_t& pos)
161     {
162         return " at line " + std::to_string(pos.lines_read + 1) +
163                ", column " + std::to_string(pos.chars_read_current_line);
164     }
165 };
166 
167 /*!
168 @brief exception indicating errors with iterators
169 
170 This exception is thrown if iterators passed to a library function do not match
171 the expected semantics.
172 
173 Exceptions have ids 2xx.
174 
175 name / id                           | example message | description
176 ----------------------------------- | --------------- | -------------------------
177 json.exception.invalid_iterator.201 | iterators are not compatible | The iterators passed to constructor @ref basic_json(InputIT first, InputIT last) are not compatible, meaning they do not belong to the same container. Therefore, the range (@a first, @a last) is invalid.
178 json.exception.invalid_iterator.202 | iterator does not fit current value | In an erase or insert function, the passed iterator @a pos does not belong to the JSON value for which the function was called. It hence does not define a valid position for the deletion/insertion.
179 json.exception.invalid_iterator.203 | iterators do not fit current value | Either iterator passed to function @ref erase(IteratorType first, IteratorType last) does not belong to the JSON value from which values shall be erased. It hence does not define a valid range to delete values from.
180 json.exception.invalid_iterator.204 | iterators out of range | When an iterator range for a primitive type (number, boolean, or string) is passed to a constructor or an erase function, this range has to be exactly (@ref begin(), @ref end()), because this is the only way the single stored value is expressed. All other ranges are invalid.
181 json.exception.invalid_iterator.205 | iterator out of range | When an iterator for a primitive type (number, boolean, or string) is passed to an erase function, the iterator has to be the @ref begin() iterator, because it is the only way to address the stored value. All other iterators are invalid.
182 json.exception.invalid_iterator.206 | cannot construct with iterators from null | The iterators passed to constructor @ref basic_json(InputIT first, InputIT last) belong to a JSON null value and hence to not define a valid range.
183 json.exception.invalid_iterator.207 | cannot use key() for non-object iterators | The key() member function can only be used on iterators belonging to a JSON object, because other types do not have a concept of a key.
184 json.exception.invalid_iterator.208 | cannot use operator[] for object iterators | The operator[] to specify a concrete offset cannot be used on iterators belonging to a JSON object, because JSON objects are unordered.
185 json.exception.invalid_iterator.209 | cannot use offsets with object iterators | The offset operators (+, -, +=, -=) cannot be used on iterators belonging to a JSON object, because JSON objects are unordered.
186 json.exception.invalid_iterator.210 | iterators do not fit | The iterator range passed to the insert function are not compatible, meaning they do not belong to the same container. Therefore, the range (@a first, @a last) is invalid.
187 json.exception.invalid_iterator.211 | passed iterators may not belong to container | The iterator range passed to the insert function must not be a subrange of the container to insert to.
188 json.exception.invalid_iterator.212 | cannot compare iterators of different containers | When two iterators are compared, they must belong to the same container.
189 json.exception.invalid_iterator.213 | cannot compare order of object iterators | The order of object iterators cannot be compared, because JSON objects are unordered.
190 json.exception.invalid_iterator.214 | cannot get value | Cannot get value for iterator: Either the iterator belongs to a null value or it is an iterator to a primitive type (number, boolean, or string), but the iterator is different to @ref begin().
191 
192 @liveexample{The following code shows how an `invalid_iterator` exception can be
193 caught.,invalid_iterator}
194 
195 @sa - @ref exception for the base class of the library exceptions
196 @sa - @ref parse_error for exceptions indicating a parse error
197 @sa - @ref type_error for exceptions indicating executing a member function with
198                     a wrong type
199 @sa - @ref out_of_range for exceptions indicating access out of the defined range
200 @sa - @ref other_error for exceptions indicating other library errors
201 
202 @since version 3.0.0
203 */
204 class invalid_iterator : public exception
205 {
206   public:
create(int id_,const std::string & what_arg)207     static invalid_iterator create(int id_, const std::string& what_arg)
208     {
209         std::string w = exception::name("invalid_iterator", id_) + what_arg;
210         return invalid_iterator(id_, w.c_str());
211     }
212 
213   private:
214     JSON_HEDLEY_NON_NULL(3)
invalid_iterator(int id_,const char * what_arg)215     invalid_iterator(int id_, const char* what_arg)
216         : exception(id_, what_arg) {}
217 };
218 
219 /*!
220 @brief exception indicating executing a member function with a wrong type
221 
222 This exception is thrown in case of a type error; that is, a library function is
223 executed on a JSON value whose type does not match the expected semantics.
224 
225 Exceptions have ids 3xx.
226 
227 name / id                     | example message | description
228 ----------------------------- | --------------- | -------------------------
229 json.exception.type_error.301 | cannot create object from initializer list | To create an object from an initializer list, the initializer list must consist only of a list of pairs whose first element is a string. When this constraint is violated, an array is created instead.
230 json.exception.type_error.302 | type must be object, but is array | During implicit or explicit value conversion, the JSON type must be compatible to the target type. For instance, a JSON string can only be converted into string types, but not into numbers or boolean types.
231 json.exception.type_error.303 | incompatible ReferenceType for get_ref, actual type is object | To retrieve a reference to a value stored in a @ref basic_json object with @ref get_ref, the type of the reference must match the value type. For instance, for a JSON array, the @a ReferenceType must be @ref array_t &.
232 json.exception.type_error.304 | cannot use at() with string | The @ref at() member functions can only be executed for certain JSON types.
233 json.exception.type_error.305 | cannot use operator[] with string | The @ref operator[] member functions can only be executed for certain JSON types.
234 json.exception.type_error.306 | cannot use value() with string | The @ref value() member functions can only be executed for certain JSON types.
235 json.exception.type_error.307 | cannot use erase() with string | The @ref erase() member functions can only be executed for certain JSON types.
236 json.exception.type_error.308 | cannot use push_back() with string | The @ref push_back() and @ref operator+= member functions can only be executed for certain JSON types.
237 json.exception.type_error.309 | cannot use insert() with | The @ref insert() member functions can only be executed for certain JSON types.
238 json.exception.type_error.310 | cannot use swap() with number | The @ref swap() member functions can only be executed for certain JSON types.
239 json.exception.type_error.311 | cannot use emplace_back() with string | The @ref emplace_back() member function can only be executed for certain JSON types.
240 json.exception.type_error.312 | cannot use update() with string | The @ref update() member functions can only be executed for certain JSON types.
241 json.exception.type_error.313 | invalid value to unflatten | The @ref unflatten function converts an object whose keys are JSON Pointers back into an arbitrary nested JSON value. The JSON Pointers must not overlap, because then the resulting value would not be well defined.
242 json.exception.type_error.314 | only objects can be unflattened | The @ref unflatten function only works for an object whose keys are JSON Pointers.
243 json.exception.type_error.315 | values in object must be primitive | The @ref unflatten function only works for an object whose keys are JSON Pointers and whose values are primitive.
244 json.exception.type_error.316 | invalid UTF-8 byte at index 10: 0x7E | The @ref dump function only works with UTF-8 encoded strings; that is, if you assign a `std::string` to a JSON value, make sure it is UTF-8 encoded. |
245 json.exception.type_error.317 | JSON value cannot be serialized to requested format | The dynamic type of the object cannot be represented in the requested serialization format (e.g. a raw `true` or `null` JSON object cannot be serialized to BSON) |
246 
247 @liveexample{The following code shows how a `type_error` exception can be
248 caught.,type_error}
249 
250 @sa - @ref exception for the base class of the library exceptions
251 @sa - @ref parse_error for exceptions indicating a parse error
252 @sa - @ref invalid_iterator for exceptions indicating errors with iterators
253 @sa - @ref out_of_range for exceptions indicating access out of the defined range
254 @sa - @ref other_error for exceptions indicating other library errors
255 
256 @since version 3.0.0
257 */
258 class type_error : public exception
259 {
260   public:
create(int id_,const std::string & what_arg)261     static type_error create(int id_, const std::string& what_arg)
262     {
263         std::string w = exception::name("type_error", id_) + what_arg;
264         return type_error(id_, w.c_str());
265     }
266 
267   private:
268     JSON_HEDLEY_NON_NULL(3)
type_error(int id_,const char * what_arg)269     type_error(int id_, const char* what_arg) : exception(id_, what_arg) {}
270 };
271 
272 /*!
273 @brief exception indicating access out of the defined range
274 
275 This exception is thrown in case a library function is called on an input
276 parameter that exceeds the expected range, for instance in case of array
277 indices or nonexisting object keys.
278 
279 Exceptions have ids 4xx.
280 
281 name / id                       | example message | description
282 ------------------------------- | --------------- | -------------------------
283 json.exception.out_of_range.401 | array index 3 is out of range | The provided array index @a i is larger than @a size-1.
284 json.exception.out_of_range.402 | array index '-' (3) is out of range | The special array index `-` in a JSON Pointer never describes a valid element of the array, but the index past the end. That is, it can only be used to add elements at this position, but not to read it.
285 json.exception.out_of_range.403 | key 'foo' not found | The provided key was not found in the JSON object.
286 json.exception.out_of_range.404 | unresolved reference token 'foo' | A reference token in a JSON Pointer could not be resolved.
287 json.exception.out_of_range.405 | JSON pointer has no parent | The JSON Patch operations 'remove' and 'add' can not be applied to the root element of the JSON value.
288 json.exception.out_of_range.406 | number overflow parsing '10E1000' | A parsed number could not be stored as without changing it to NaN or INF.
289 json.exception.out_of_range.407 | number overflow serializing '9223372036854775808' | UBJSON and BSON only support integer numbers up to 9223372036854775807. (until version 3.8.0) |
290 json.exception.out_of_range.408 | excessive array size: 8658170730974374167 | The size (following `#`) of an UBJSON array or object exceeds the maximal capacity. |
291 json.exception.out_of_range.409 | BSON key cannot contain code point U+0000 (at byte 2) | Key identifiers to be serialized to BSON cannot contain code point U+0000, since the key is stored as zero-terminated c-string |
292 
293 @liveexample{The following code shows how an `out_of_range` exception can be
294 caught.,out_of_range}
295 
296 @sa - @ref exception for the base class of the library exceptions
297 @sa - @ref parse_error for exceptions indicating a parse error
298 @sa - @ref invalid_iterator for exceptions indicating errors with iterators
299 @sa - @ref type_error for exceptions indicating executing a member function with
300                     a wrong type
301 @sa - @ref other_error for exceptions indicating other library errors
302 
303 @since version 3.0.0
304 */
305 class out_of_range : public exception
306 {
307   public:
create(int id_,const std::string & what_arg)308     static out_of_range create(int id_, const std::string& what_arg)
309     {
310         std::string w = exception::name("out_of_range", id_) + what_arg;
311         return out_of_range(id_, w.c_str());
312     }
313 
314   private:
315     JSON_HEDLEY_NON_NULL(3)
out_of_range(int id_,const char * what_arg)316     out_of_range(int id_, const char* what_arg) : exception(id_, what_arg) {}
317 };
318 
319 /*!
320 @brief exception indicating other library errors
321 
322 This exception is thrown in case of errors that cannot be classified with the
323 other exception types.
324 
325 Exceptions have ids 5xx.
326 
327 name / id                      | example message | description
328 ------------------------------ | --------------- | -------------------------
329 json.exception.other_error.501 | unsuccessful: {"op":"test","path":"/baz", "value":"bar"} | A JSON Patch operation 'test' failed. The unsuccessful operation is also printed.
330 
331 @sa - @ref exception for the base class of the library exceptions
332 @sa - @ref parse_error for exceptions indicating a parse error
333 @sa - @ref invalid_iterator for exceptions indicating errors with iterators
334 @sa - @ref type_error for exceptions indicating executing a member function with
335                     a wrong type
336 @sa - @ref out_of_range for exceptions indicating access out of the defined range
337 
338 @liveexample{The following code shows how an `other_error` exception can be
339 caught.,other_error}
340 
341 @since version 3.0.0
342 */
343 class other_error : public exception
344 {
345   public:
create(int id_,const std::string & what_arg)346     static other_error create(int id_, const std::string& what_arg)
347     {
348         std::string w = exception::name("other_error", id_) + what_arg;
349         return other_error(id_, w.c_str());
350     }
351 
352   private:
353     JSON_HEDLEY_NON_NULL(3)
other_error(int id_,const char * what_arg)354     other_error(int id_, const char* what_arg) : exception(id_, what_arg) {}
355 };
356 }  // namespace detail
357 }  // namespace nlohmann
358