diff options
Diffstat (limited to 'third_party/chromium/base/json/json_parser.cc')
-rw-r--r-- | third_party/chromium/base/json/json_parser.cc | 82 |
1 files changed, 44 insertions, 38 deletions
diff --git a/third_party/chromium/base/json/json_parser.cc b/third_party/chromium/base/json/json_parser.cc index 304a7bd..708965a 100644 --- a/third_party/chromium/base/json/json_parser.cc +++ b/third_party/chromium/base/json/json_parser.cc @@ -5,10 +5,11 @@ #include "base/json/json_parser.h" #include <cmath> +#include <utility> #include "base/logging.h" #include "base/macros.h" -#include "base/memory/scoped_ptr.h" +#include "base/memory/ptr_util.h" #include "base/strings/string_number_conversions.h" #include "base/strings/string_piece.h" #include "base/strings/string_util.h" @@ -26,16 +27,19 @@ const int kStackMaxDepth = 100; const int32_t kExtendedASCIIStart = 0x80; -// This and the class below are used to own the JSON input string for when -// string tokens are stored as StringPiece instead of std::string. This -// optimization avoids about 2/3rds of string memory copies. The constructor -// takes ownership of the input string. The real root value is Swap()ed into -// the new instance. +// DictionaryHiddenRootValue and ListHiddenRootValue are used in conjunction +// with JSONStringValue as an optimization for reducing the number of string +// copies. When this optimization is active, the parser uses a hidden root to +// keep the original JSON input string live and creates JSONStringValue children +// holding StringPiece references to the input string, avoiding about 2/3rds of +// string memory copies. The real root value is Swap()ed into the new instance. class DictionaryHiddenRootValue : public DictionaryValue { public: - DictionaryHiddenRootValue(std::string* json, Value* root) : json_(json) { + DictionaryHiddenRootValue(std::unique_ptr<std::string> json, + std::unique_ptr<Value> root) + : json_(std::move(json)) { DCHECK(root->IsType(Value::TYPE_DICTIONARY)); - DictionaryValue::Swap(static_cast<DictionaryValue*>(root)); + DictionaryValue::Swap(static_cast<DictionaryValue*>(root.get())); } void Swap(DictionaryValue* other) override { @@ -43,7 +47,7 @@ class DictionaryHiddenRootValue : public DictionaryValue { // First deep copy to convert JSONStringValue to std::string and swap that // copy with |other|, which contains the new contents of |this|. - scoped_ptr<DictionaryValue> copy(DeepCopy()); + std::unique_ptr<DictionaryValue> copy(CreateDeepCopy()); copy->Swap(other); // Then erase the contents of the current dictionary and swap in the @@ -57,7 +61,7 @@ class DictionaryHiddenRootValue : public DictionaryValue { // the method below. bool RemoveWithoutPathExpansion(const std::string& key, - scoped_ptr<Value>* out) override { + std::unique_ptr<Value>* out) override { // If the caller won't take ownership of the removed value, just call up. if (!out) return DictionaryValue::RemoveWithoutPathExpansion(key, out); @@ -66,26 +70,28 @@ class DictionaryHiddenRootValue : public DictionaryValue { // Otherwise, remove the value while its still "owned" by this and copy it // to convert any JSONStringValues to std::string. - scoped_ptr<Value> out_owned; + std::unique_ptr<Value> out_owned; if (!DictionaryValue::RemoveWithoutPathExpansion(key, &out_owned)) return false; - out->reset(out_owned->DeepCopy()); + *out = out_owned->CreateDeepCopy(); return true; } private: - scoped_ptr<std::string> json_; + std::unique_ptr<std::string> json_; DISALLOW_COPY_AND_ASSIGN(DictionaryHiddenRootValue); }; class ListHiddenRootValue : public ListValue { public: - ListHiddenRootValue(std::string* json, Value* root) : json_(json) { + ListHiddenRootValue(std::unique_ptr<std::string> json, + std::unique_ptr<Value> root) + : json_(std::move(json)) { DCHECK(root->IsType(Value::TYPE_LIST)); - ListValue::Swap(static_cast<ListValue*>(root)); + ListValue::Swap(static_cast<ListValue*>(root.get())); } void Swap(ListValue* other) override { @@ -93,7 +99,7 @@ class ListHiddenRootValue : public ListValue { // First deep copy to convert JSONStringValue to std::string and swap that // copy with |other|, which contains the new contents of |this|. - scoped_ptr<ListValue> copy(DeepCopy()); + std::unique_ptr<ListValue> copy(CreateDeepCopy()); copy->Swap(other); // Then erase the contents of the current list and swap in the new contents, @@ -103,7 +109,7 @@ class ListHiddenRootValue : public ListValue { ListValue::Swap(copy.get()); } - bool Remove(size_t index, scoped_ptr<Value>* out) override { + bool Remove(size_t index, std::unique_ptr<Value>* out) override { // If the caller won't take ownership of the removed value, just call up. if (!out) return ListValue::Remove(index, out); @@ -112,17 +118,17 @@ class ListHiddenRootValue : public ListValue { // Otherwise, remove the value while its still "owned" by this and copy it // to convert any JSONStringValues to std::string. - scoped_ptr<Value> out_owned; + std::unique_ptr<Value> out_owned; if (!ListValue::Remove(index, &out_owned)) return false; - out->reset(out_owned->DeepCopy()); + *out = out_owned->CreateDeepCopy(); return true; } private: - scoped_ptr<std::string> json_; + std::unique_ptr<std::string> json_; DISALLOW_COPY_AND_ASSIGN(ListHiddenRootValue); }; @@ -132,10 +138,8 @@ class ListHiddenRootValue : public ListValue { // otherwise the referenced string will not be guaranteed to outlive it. class JSONStringValue : public Value { public: - explicit JSONStringValue(const StringPiece& piece) - : Value(TYPE_STRING), - string_piece_(piece) { - } + explicit JSONStringValue(StringPiece piece) + : Value(TYPE_STRING), string_piece_(piece) {} // Overridden from Value: bool GetAsString(std::string* out_value) const override { @@ -198,13 +202,13 @@ JSONParser::JSONParser(int options) JSONParser::~JSONParser() { } -Value* JSONParser::Parse(const StringPiece& input) { - scoped_ptr<std::string> input_copy; +std::unique_ptr<Value> JSONParser::Parse(StringPiece input) { + std::unique_ptr<std::string> input_copy; // If the children of a JSON root can be detached, then hidden roots cannot // be used, so do not bother copying the input because StringPiece will not // be used anywhere. if (!(options_ & JSON_DETACHABLE_CHILDREN)) { - input_copy.reset(new std::string(input.as_string())); + input_copy = WrapUnique(new std::string(input.as_string())); start_pos_ = input_copy->data(); } else { start_pos_ = input.data(); @@ -230,15 +234,15 @@ Value* JSONParser::Parse(const StringPiece& input) { } // Parse the first and any nested tokens. - scoped_ptr<Value> root(ParseNextToken()); - if (!root.get()) - return NULL; + std::unique_ptr<Value> root(ParseNextToken()); + if (!root) + return nullptr; // Make sure the input stream is at an end. if (GetNextToken() != T_END_OF_INPUT) { if (!CanConsume(1) || (NextChar() && GetNextToken() != T_END_OF_INPUT)) { ReportError(JSONReader::JSON_UNEXPECTED_DATA_AFTER_ROOT, 1); - return NULL; + return nullptr; } } @@ -246,19 +250,21 @@ Value* JSONParser::Parse(const StringPiece& input) { // hidden root. if (!(options_ & JSON_DETACHABLE_CHILDREN)) { if (root->IsType(Value::TYPE_DICTIONARY)) { - return new DictionaryHiddenRootValue(input_copy.release(), root.get()); + return WrapUnique(new DictionaryHiddenRootValue(std::move(input_copy), + std::move(root))); } else if (root->IsType(Value::TYPE_LIST)) { - return new ListHiddenRootValue(input_copy.release(), root.get()); + return WrapUnique( + new ListHiddenRootValue(std::move(input_copy), std::move(root))); } else if (root->IsType(Value::TYPE_STRING)) { // A string type could be a JSONStringValue, but because there's no // corresponding HiddenRootValue, the memory will be lost. Deep copy to // preserve it. - return root->DeepCopy(); + return root->CreateDeepCopy(); } } // All other values can be returned directly. - return root.release(); + return root; } JSONReader::JsonParseError JSONParser::error_code() const { @@ -304,7 +310,7 @@ JSONParser::StringBuilder::~StringBuilder() { void JSONParser::StringBuilder::Append(const char& c) { DCHECK_GE(c, 0); - DCHECK_LT(c, 128); + DCHECK_LT(static_cast<unsigned char>(c), 128); if (string_) string_->push_back(c); @@ -494,7 +500,7 @@ Value* JSONParser::ConsumeDictionary() { return NULL; } - scoped_ptr<DictionaryValue> dict(new DictionaryValue); + std::unique_ptr<DictionaryValue> dict(new DictionaryValue); NextChar(); Token token = GetNextToken(); @@ -558,7 +564,7 @@ Value* JSONParser::ConsumeList() { return NULL; } - scoped_ptr<ListValue> list(new ListValue); + std::unique_ptr<ListValue> list(new ListValue); NextChar(); Token token = GetNextToken(); |