1// Copyright (c) 2012 The Chromium Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style license that can be 3// found in the LICENSE file. 4 5#include "base/json/json_reader.h" 6 7#include <utility> 8#include <vector> 9 10#include "base/json/json_parser.h" 11#include "base/logging.h" 12#include "base/values.h" 13 14namespace base { 15 16// Chosen to support 99.9% of documents found in the wild late 2016. 17// http://crbug.com/673263 18const int JSONReader::kStackMaxDepth = 200; 19 20// Values 1000 and above are used by JSONFileValueSerializer::JsonFileError. 21static_assert(JSONReader::JSON_PARSE_ERROR_COUNT < 1000, 22 "JSONReader error out of bounds"); 23 24const char JSONReader::kInvalidEscape[] = "Invalid escape sequence."; 25const char JSONReader::kSyntaxError[] = "Syntax error."; 26const char JSONReader::kUnexpectedToken[] = "Unexpected token."; 27const char JSONReader::kTrailingComma[] = "Trailing comma not allowed."; 28const char JSONReader::kTooMuchNesting[] = "Too much nesting."; 29const char JSONReader::kUnexpectedDataAfterRoot[] = 30 "Unexpected data after root element."; 31const char JSONReader::kUnsupportedEncoding[] = 32 "Unsupported encoding. JSON must be UTF-8."; 33const char JSONReader::kUnquotedDictionaryKey[] = 34 "Dictionary keys must be quoted."; 35const char JSONReader::kInputTooLarge[] = "Input string is too large (>2GB)."; 36 37JSONReader::JSONReader(int options, int max_depth) 38 : parser_(new internal::JSONParser(options, max_depth)) {} 39 40JSONReader::~JSONReader() = default; 41 42// static 43std::unique_ptr<Value> JSONReader::Read(std::string_view json, 44 int options, 45 int max_depth) { 46 internal::JSONParser parser(options, max_depth); 47 std::optional<Value> root = parser.Parse(json); 48 return root ? std::make_unique<Value>(std::move(*root)) : nullptr; 49} 50 51// static 52std::unique_ptr<Value> JSONReader::ReadAndReturnError( 53 std::string_view json, 54 int options, 55 int* error_code_out, 56 std::string* error_msg_out, 57 int* error_line_out, 58 int* error_column_out) { 59 internal::JSONParser parser(options); 60 std::optional<Value> root = parser.Parse(json); 61 if (!root) { 62 if (error_code_out) 63 *error_code_out = parser.error_code(); 64 if (error_msg_out) 65 *error_msg_out = parser.GetErrorMessage(); 66 if (error_line_out) 67 *error_line_out = parser.error_line(); 68 if (error_column_out) 69 *error_column_out = parser.error_column(); 70 } 71 72 return root ? std::make_unique<Value>(std::move(*root)) : nullptr; 73} 74 75// static 76std::string JSONReader::ErrorCodeToString(JsonParseError error_code) { 77 switch (error_code) { 78 case JSON_NO_ERROR: 79 return std::string(); 80 case JSON_INVALID_ESCAPE: 81 return kInvalidEscape; 82 case JSON_SYNTAX_ERROR: 83 return kSyntaxError; 84 case JSON_UNEXPECTED_TOKEN: 85 return kUnexpectedToken; 86 case JSON_TRAILING_COMMA: 87 return kTrailingComma; 88 case JSON_TOO_MUCH_NESTING: 89 return kTooMuchNesting; 90 case JSON_UNEXPECTED_DATA_AFTER_ROOT: 91 return kUnexpectedDataAfterRoot; 92 case JSON_UNSUPPORTED_ENCODING: 93 return kUnsupportedEncoding; 94 case JSON_UNQUOTED_DICTIONARY_KEY: 95 return kUnquotedDictionaryKey; 96 case JSON_TOO_LARGE: 97 return kInputTooLarge; 98 case JSON_PARSE_ERROR_COUNT: 99 break; 100 } 101 NOTREACHED(); 102 return std::string(); 103} 104 105std::unique_ptr<Value> JSONReader::ReadToValue(std::string_view json) { 106 std::optional<Value> value = parser_->Parse(json); 107 return value ? std::make_unique<Value>(std::move(*value)) : nullptr; 108} 109 110JSONReader::JsonParseError JSONReader::error_code() const { 111 return parser_->error_code(); 112} 113 114std::string JSONReader::GetErrorMessage() const { 115 return parser_->GetErrorMessage(); 116} 117 118} // namespace base 119