|  | // Copyright (c) 2012 The Chromium Authors. All rights reserved. | 
|  | // Use of this source code is governed by a BSD-style license that can be | 
|  | // found in the LICENSE file. | 
|  |  | 
|  | #ifndef BASE_JSON_JSON_FILE_VALUE_SERIALIZER_H_ | 
|  | #define BASE_JSON_JSON_FILE_VALUE_SERIALIZER_H_ | 
|  |  | 
|  | #include <stddef.h> | 
|  |  | 
|  | #include <string> | 
|  |  | 
|  | #include "base/base_export.h" | 
|  | #include "base/files/file_path.h" | 
|  | #include "base/macros.h" | 
|  | #include "base/values.h" | 
|  |  | 
|  | class BASE_EXPORT JSONFileValueSerializer : public base::ValueSerializer { | 
|  | public: | 
|  | // |json_file_path_| is the path of a file that will be destination of the | 
|  | // serialization. The serializer will attempt to create the file at the | 
|  | // specified location. | 
|  | explicit JSONFileValueSerializer(const base::FilePath& json_file_path); | 
|  |  | 
|  | ~JSONFileValueSerializer() override; | 
|  |  | 
|  | // DO NOT USE except in unit tests to verify the file was written properly. | 
|  | // We should never serialize directly to a file since this will block the | 
|  | // thread. Instead, serialize to a string and write to the file you want on | 
|  | // the file thread. | 
|  | // | 
|  | // Attempt to serialize the data structure represented by Value into | 
|  | // JSON.  If the return value is true, the result will have been written | 
|  | // into the file whose name was passed into the constructor. | 
|  | bool Serialize(const base::Value& root) override; | 
|  |  | 
|  | // Equivalent to Serialize(root) except binary values are omitted from the | 
|  | // output. | 
|  | bool SerializeAndOmitBinaryValues(const base::Value& root); | 
|  |  | 
|  | private: | 
|  | bool SerializeInternal(const base::Value& root, bool omit_binary_values); | 
|  |  | 
|  | const base::FilePath json_file_path_; | 
|  |  | 
|  | DISALLOW_IMPLICIT_CONSTRUCTORS(JSONFileValueSerializer); | 
|  | }; | 
|  |  | 
|  | class BASE_EXPORT JSONFileValueDeserializer : public base::ValueDeserializer { | 
|  | public: | 
|  | // |json_file_path_| is the path of a file that will be source of the | 
|  | // deserialization. |options| is a bitmask of JSONParserOptions. | 
|  | explicit JSONFileValueDeserializer(const base::FilePath& json_file_path, | 
|  | int options = 0); | 
|  |  | 
|  | ~JSONFileValueDeserializer() override; | 
|  |  | 
|  | // Attempt to deserialize the data structure encoded in the file passed | 
|  | // in to the constructor into a structure of Value objects.  If the return | 
|  | // value is NULL, and if |error_code| is non-null, |error_code| will | 
|  | // contain an integer error code (either JsonFileError or JsonParseError). | 
|  | // If |error_message| is non-null, it will be filled in with a formatted | 
|  | // error message including the location of the error if appropriate. | 
|  | // The caller takes ownership of the returned value. | 
|  | std::unique_ptr<base::Value> Deserialize(int* error_code, | 
|  | std::string* error_message) override; | 
|  |  | 
|  | // This enum is designed to safely overlap with JSONReader::JsonParseError. | 
|  | enum JsonFileError { | 
|  | JSON_NO_ERROR = 0, | 
|  | JSON_ACCESS_DENIED = 1000, | 
|  | JSON_CANNOT_READ_FILE, | 
|  | JSON_FILE_LOCKED, | 
|  | JSON_NO_SUCH_FILE | 
|  | }; | 
|  |  | 
|  | // File-specific error messages that can be returned. | 
|  | static const char kAccessDenied[]; | 
|  | static const char kCannotReadFile[]; | 
|  | static const char kFileLocked[]; | 
|  | static const char kNoSuchFile[]; | 
|  |  | 
|  | // Convert an error code into an error message.  |error_code| is assumed to | 
|  | // be a JsonFileError. | 
|  | static const char* GetErrorMessageForCode(int error_code); | 
|  |  | 
|  | // Returns the size (in bytes) of JSON string read from disk in the last | 
|  | // successful |Deserialize()| call. | 
|  | size_t get_last_read_size() const { return last_read_size_; } | 
|  |  | 
|  | private: | 
|  | // A wrapper for ReadFileToString which returns a non-zero JsonFileError if | 
|  | // there were file errors. | 
|  | int ReadFileToString(std::string* json_string); | 
|  |  | 
|  | const base::FilePath json_file_path_; | 
|  | const int options_; | 
|  | size_t last_read_size_; | 
|  |  | 
|  | DISALLOW_IMPLICIT_CONSTRUCTORS(JSONFileValueDeserializer); | 
|  | }; | 
|  |  | 
|  | #endif  // BASE_JSON_JSON_FILE_VALUE_SERIALIZER_H_ | 
|  |  |