blob: 912a7f0ad50fd493e0dd3c3e5bad7d55a4c79551 [file] [log] [blame]
// 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.
#include "base/json/json_writer.h"
#include <stdint.h>
#include <cmath>
#include <limits>
#include "base/json/string_escape.h"
#include "base/logging.h"
#include "base/strings/string_number_conversions.h"
#include "base/strings/utf_string_conversions.h"
#include "base/values.h"
#include "util/build_config.h"
namespace base {
#if defined(OS_WIN)
const char kPrettyPrintLineEnding[] = "\r\n";
#else
const char kPrettyPrintLineEnding[] = "\n";
#endif
// static
bool JSONWriter::Write(const Value& node, std::string* json) {
return WriteWithOptions(node, 0, json);
}
// static
bool JSONWriter::WriteWithOptions(const Value& node,
int options,
std::string* json) {
json->clear();
// Is there a better way to estimate the size of the output?
json->reserve(1024);
JSONWriter writer(options, json);
bool result = writer.BuildJSONString(node, 0U);
if (options & OPTIONS_PRETTY_PRINT)
json->append(kPrettyPrintLineEnding);
return result;
}
JSONWriter::JSONWriter(int options, std::string* json)
: omit_binary_values_((options & OPTIONS_OMIT_BINARY_VALUES) != 0),
pretty_print_((options & OPTIONS_PRETTY_PRINT) != 0),
json_string_(json) {
DCHECK(json);
}
bool JSONWriter::BuildJSONString(const Value& node, size_t depth) {
switch (node.type()) {
case Value::Type::NONE: {
json_string_->append("null");
return true;
}
case Value::Type::BOOLEAN: {
bool value;
bool result = node.GetAsBoolean(&value);
DCHECK(result);
json_string_->append(value ? "true" : "false");
return result;
}
case Value::Type::INTEGER: {
int value;
bool result = node.GetAsInteger(&value);
DCHECK(result);
json_string_->append(IntToString(value));
return result;
}
case Value::Type::STRING: {
std::string value;
bool result = node.GetAsString(&value);
DCHECK(result);
EscapeJSONString(value, true, json_string_);
return result;
}
case Value::Type::LIST: {
json_string_->push_back('[');
if (pretty_print_)
json_string_->push_back(' ');
const ListValue* list = nullptr;
bool first_value_has_been_output = false;
bool result = node.GetAsList(&list);
DCHECK(result);
for (const auto& value : *list) {
if (omit_binary_values_ && value.type() == Value::Type::BINARY)
continue;
if (first_value_has_been_output) {
json_string_->push_back(',');
if (pretty_print_)
json_string_->push_back(' ');
}
if (!BuildJSONString(value, depth))
result = false;
first_value_has_been_output = true;
}
if (pretty_print_)
json_string_->push_back(' ');
json_string_->push_back(']');
return result;
}
case Value::Type::DICTIONARY: {
json_string_->push_back('{');
if (pretty_print_)
json_string_->append(kPrettyPrintLineEnding);
const DictionaryValue* dict = nullptr;
bool first_value_has_been_output = false;
bool result = node.GetAsDictionary(&dict);
DCHECK(result);
for (DictionaryValue::Iterator itr(*dict); !itr.IsAtEnd();
itr.Advance()) {
if (omit_binary_values_ && itr.value().type() == Value::Type::BINARY) {
continue;
}
if (first_value_has_been_output) {
json_string_->push_back(',');
if (pretty_print_)
json_string_->append(kPrettyPrintLineEnding);
}
if (pretty_print_)
IndentLine(depth + 1U);
EscapeJSONString(itr.key(), true, json_string_);
json_string_->push_back(':');
if (pretty_print_)
json_string_->push_back(' ');
if (!BuildJSONString(itr.value(), depth + 1U))
result = false;
first_value_has_been_output = true;
}
if (pretty_print_) {
json_string_->append(kPrettyPrintLineEnding);
IndentLine(depth);
}
json_string_->push_back('}');
return result;
}
case Value::Type::BINARY:
// Successful only if we're allowed to omit it.
DLOG_IF(ERROR, !omit_binary_values_) << "Cannot serialize binary value.";
return omit_binary_values_;
}
NOTREACHED();
return false;
}
void JSONWriter::IndentLine(size_t depth) {
json_string_->append(depth * 3U, ' ');
}
} // namespace base