/* This Source Code Form is subject to the terms of the Mozilla Public * License, v. 2.0. If a copy of the MPL was not distributed with this * file, You can obtain one at http://mozilla.org/MPL/2.0/. */ /* * JSON serialization and deserialization operations. */ #ifndef js_JSON_h #define js_JSON_h #include // uint32_t #include "jstypes.h" // JS_PUBLIC_API #include "js/TypeDecls.h" using JSONWriteCallback = bool (*)(const char16_t* buf, uint32_t len, void* data); /** * Performs the JSON.stringify operation, as specified by ECMAScript, except * writing stringified data by exactly one call of |callback|, passing |data| as * argument. * * In cases where JSON.stringify would return undefined, this function calls * |callback| with the string "null". * * If a length hint is passed, space will be reserved for at least that many * characters. */ extern JS_PUBLIC_API bool JS_Stringify(JSContext* cx, JS::MutableHandle value, JS::Handle replacer, JS::Handle space, JSONWriteCallback callback, void* data); extern JS_PUBLIC_API bool JS_StringifyWithLengthHint( JSContext* cx, JS::MutableHandle value, JS::Handle replacer, JS::Handle space, JSONWriteCallback callback, void* data, size_t lengthHint); namespace JS { /** * An API akin to JS_Stringify but with the goal of not having observable * side-effects when the stringification is performed. This means it does not * allow a replacer or a custom space and has the following constraints on its * input: * * 1) The input must be a plain object or array, not an arbitrary value. * 2) Every value in the graph reached by the algorithm starting with this * object must be one of the following: null, undefined, a string (NOT a * string object!), a boolean, a finite number (i.e. no NaN or Infinity or * -Infinity), a plain object with no accessor properties, or an Array with * no holes. * * The actual behavior differs from JS_Stringify only in asserting the above and * NOT attempting to get the "toJSON" property from things, since that could * clearly have side-effects. */ extern JS_PUBLIC_API bool ToJSONMaybeSafely(JSContext* cx, JS::Handle input, JSONWriteCallback callback, void* data); /** * Performs the JSON.stringify operation, as specified by ECMAScript, except * writing stringified data by one call of |callback|, passing |data| as * argument. * * In cases where JSON.stringify would return undefined, this function does not * call |callback| at all. */ extern JS_PUBLIC_API bool ToJSON(JSContext* cx, Handle value, Handle replacer, Handle space, JSONWriteCallback callback, void* data); } /* namespace JS */ /** * Performs the JSON.parse operation as specified by ECMAScript. */ extern JS_PUBLIC_API bool JS_ParseJSON(JSContext* cx, const char16_t* chars, uint32_t len, JS::MutableHandle vp); /** * Performs the JSON.parse operation as specified by ECMAScript. */ extern JS_PUBLIC_API bool JS_ParseJSON(JSContext* cx, JS::Handle str, JS::MutableHandle vp); /** * Performs the JSON.parse operation as specified by ECMAScript. */ extern JS_PUBLIC_API bool JS_ParseJSON(JSContext* cx, const JS::Latin1Char* chars, uint32_t len, JS::MutableHandle vp); /** * Performs the JSON.parse operation as specified by ECMAScript, using the * given |reviver| argument as the corresponding optional argument to that * function. */ extern JS_PUBLIC_API bool JS_ParseJSONWithReviver( JSContext* cx, const char16_t* chars, uint32_t len, JS::Handle reviver, JS::MutableHandle vp); /** * Performs the JSON.parse operation as specified by ECMAScript, using the * given |reviver| argument as the corresponding optional argument to that * function. */ extern JS_PUBLIC_API bool JS_ParseJSONWithReviver( JSContext* cx, JS::Handle str, JS::Handle reviver, JS::MutableHandle vp); namespace JS { /** * Returns true if the given text is valid JSON. */ extern JS_PUBLIC_API bool IsValidJSON(const JS::Latin1Char* chars, uint32_t len); extern JS_PUBLIC_API bool IsValidJSON(const char16_t* chars, uint32_t len); /** * Handler with callbacks for JS::ParseJSONWithHandler. * * Each method is called during parsing the JSON string. If the method returns * true, the parsing keeps going. If the method returns false, the parsing * stops and fails. * * The error method is called when syntax error happens while parsing the input. * This method is not called when handler's method returns false. */ class JSONParseHandler { public: JSONParseHandler() {} virtual ~JSONParseHandler() {} // Called when '{' is found for an object. virtual bool startObject() = 0; // Called when a property name is found for an object. // The character type depends on the input type and also the content of the // property name. The consumer should implement both methods. virtual bool propertyName(const JS::Latin1Char* name, size_t length) = 0; virtual bool propertyName(const char16_t* name, size_t length) = 0; // Called when '}' is found for an object. virtual bool endObject() = 0; // Called when '[' is found for an array. virtual bool startArray() = 0; // Called when ']' is found for an array. virtual bool endArray() = 0; // Called when a string is found. // The character type depends on the input type and also the content of the // string. The consumer should implement both methods. virtual bool stringValue(const JS::Latin1Char* str, size_t length) = 0; virtual bool stringValue(const char16_t* str, size_t length) = 0; // Called when a number is found. virtual bool numberValue(double d) = 0; // Called when a boolean is found. virtual bool booleanValue(bool v) = 0; // Called when null is found. virtual bool nullValue() = 0; // Called when syntax error happens. virtual void error(const char* msg, uint32_t line, uint32_t column) = 0; }; /** * Performs the JSON.parse operation as specified by ECMAScript, and call * callbacks defined by the handler. */ extern JS_PUBLIC_API bool ParseJSONWithHandler(const JS::Latin1Char* chars, uint32_t len, JSONParseHandler* handler); extern JS_PUBLIC_API bool ParseJSONWithHandler(const char16_t* chars, uint32_t len, JSONParseHandler* handler); } // namespace JS #endif /* js_JSON_h */