path: root/src/google/protobuf/compiler/cpp/cpp_map_field.cc

// Protocol Buffers - Google's data interchange format
// Copyright 2008 Google Inc.  All rights reserved.
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#include <google/protobuf/compiler/cpp/cpp_map_field.h>
#include <google/protobuf/compiler/cpp/cpp_helpers.h>
#include <google/protobuf/io/printer.h>
#include <google/protobuf/wire_format.h>
#include <google/protobuf/stubs/strutil.h>


namespace google {
namespace protobuf {
namespace compiler {
namespace cpp {

bool IsProto3Field(const FieldDescriptor* field_descriptor) {
  const FileDescriptor* file_descriptor = field_descriptor->file();
  return file_descriptor->syntax() == FileDescriptor::SYNTAX_PROTO3;
}

void SetMessageVariables(const FieldDescriptor* descriptor,
                         std::map<string, string>* variables,
                         const Options& options) {
  SetCommonFieldVariables(descriptor, variables, options);
  (*variables)["type"] = ClassName(descriptor->message_type(), false);
  (*variables)["stream_writer"] =
      (*variables)["declared_type"] +
      (HasFastArraySerialization(descriptor->message_type()->file(), options)
           ? "MaybeToArray"
           : "");
  (*variables)["full_name"] = descriptor->full_name();

  const FieldDescriptor* key =
      descriptor->message_type()->FindFieldByName("key");
  const FieldDescriptor* val =
      descriptor->message_type()->FindFieldByName("value");
  (*variables)["key_cpp"] = PrimitiveTypeName(options, key->cpp_type());
  switch (val->cpp_type()) {
    case FieldDescriptor::CPPTYPE_MESSAGE:
      (*variables)["val_cpp"] = FieldMessageTypeName(val);
      (*variables)["wrapper"] = "EntryWrapper";
      break;
    case FieldDescriptor::CPPTYPE_ENUM:
      (*variables)["val_cpp"] = ClassName(val->enum_type(), true);
      (*variables)["wrapper"] = "EnumEntryWrapper";
      break;
    default:
      (*variables)["val_cpp"] = PrimitiveTypeName(options, val->cpp_type());
      (*variables)["wrapper"] = "EntryWrapper";
  }
  (*variables)["key_wire_type"] =
      "TYPE_" + ToUpper(DeclaredTypeMethodName(key->type()));
  (*variables)["val_wire_type"] =
      "TYPE_" + ToUpper(DeclaredTypeMethodName(val->type()));
  (*variables)["map_classname"] = ClassName(descriptor->message_type(), false);
  (*variables)["number"] = SimpleItoa(descriptor->number());
  (*variables)["tag"] =
      SimpleItoa(internal::WireFormat::MakeTag(descriptor));

  if (HasDescriptorMethods(descriptor->file(), options)) {
    (*variables)["lite"] = "";
  } else {
    (*variables)["lite"] = "Lite";
  }

  if (!IsProto3Field(descriptor) &&
      val->type() == FieldDescriptor::TYPE_ENUM) {
    const EnumValueDescriptor* default_value = val->default_value_enum();
    (*variables)["default_enum_value"] = Int32ToString(default_value->number());
  } else {
    (*variables)["default_enum_value"] = "0";
  }
}

MapFieldGenerator::MapFieldGenerator(const FieldDescriptor* descriptor,
                                     const Options& options)
    : FieldGenerator(descriptor, options) {
  SetMessageVariables(descriptor, &variables_, options);
}

MapFieldGenerator::~MapFieldGenerator() {}

void MapFieldGenerator::
GeneratePrivateMembers(io::Printer* printer) const {
  Formatter format(printer, variables_);
  format(
      "::$proto_ns$::internal::MapField$lite$<\n"
      "    $map_classname$,\n"
      "    $key_cpp$, $val_cpp$,\n"
      "    ::$proto_ns$::internal::WireFormatLite::$key_wire_type$,\n"
      "    ::$proto_ns$::internal::WireFormatLite::$val_wire_type$,\n"
      "    $default_enum_value$ > $name$_;\n");
}

void MapFieldGenerator::
GenerateAccessorDeclarations(io::Printer* printer) const {
  Formatter format(printer, variables_);
  format(
      "$deprecated_attr$const ::$proto_ns$::Map< $key_cpp$, $val_cpp$ >&\n"
      "    ${1$$name$$}$() const;\n"
      "$deprecated_attr$::$proto_ns$::Map< $key_cpp$, $val_cpp$ >*\n"
      "    ${1$mutable_$name$$}$();\n",
      descriptor_);
}

void MapFieldGenerator::
GenerateInlineAccessorDefinitions(io::Printer* printer) const {
  Formatter format(printer, variables_);
  format(
      "inline const ::$proto_ns$::Map< $key_cpp$, $val_cpp$ >&\n"
      "$classname$::$name$() const {\n"
      "  // @@protoc_insertion_point(field_map:$full_name$)\n"
      "  return $name$_.GetMap();\n"
      "}\n"
      "inline ::$proto_ns$::Map< $key_cpp$, $val_cpp$ >*\n"
      "$classname$::mutable_$name$() {\n"
      "  // @@protoc_insertion_point(field_mutable_map:$full_name$)\n"
      "  return $name$_.MutableMap();\n"
      "}\n");
}

void MapFieldGenerator::
GenerateClearingCode(io::Printer* printer) const {
  Formatter format(printer, variables_);
  format("$name$_.Clear();\n");
}

void MapFieldGenerator::
GenerateMergingCode(io::Printer* printer) const {
  Formatter format(printer, variables_);
  format("$name$_.MergeFrom(from.$name$_);\n");
}

void MapFieldGenerator::
GenerateSwappingCode(io::Printer* printer) const {
  Formatter format(printer, variables_);
  format("$name$_.Swap(&other->$name$_);\n");
}

void MapFieldGenerator::
GenerateCopyConstructorCode(io::Printer* printer) const {
  GenerateConstructorCode(printer);
  GenerateMergingCode(printer);
}

void MapFieldGenerator::
GenerateMergeFromCodedStream(io::Printer* printer) const {
  Formatter format(printer, variables_);
  const FieldDescriptor* key_field =
      descriptor_->message_type()->FindFieldByName("key");
  const FieldDescriptor* value_field =
      descriptor_->message_type()->FindFieldByName("value");
  string key;
  string value;
  format(
      "$map_classname$::Parser< ::$proto_ns$::internal::MapField$lite$<\n"
      "    $map_classname$,\n"
      "    $key_cpp$, $val_cpp$,\n"
      "    ::$proto_ns$::internal::WireFormatLite::$key_wire_type$,\n"
      "    ::$proto_ns$::internal::WireFormatLite::$val_wire_type$,\n"
      "    $default_enum_value$ >,\n"
      "  ::$proto_ns$::Map< $key_cpp$, $val_cpp$ > >"
      " parser(&$name$_);\n");
  if (IsProto3Field(descriptor_) ||
      value_field->type() != FieldDescriptor::TYPE_ENUM) {
    format(
        "DO_(::$proto_ns$::internal::WireFormatLite::ReadMessageNoVirtual(\n"
        "    input, &parser));\n");
    key = "parser.key()";
    value = "parser.value()";
  } else {
    key = "entry->key()";
    value = "entry->value()";
    format("auto entry = parser.NewEntry();\n");
    format(
        "::std::string data;\n"
        "DO_(::$proto_ns$::internal::WireFormatLite::ReadString(input, "
        "&data));\n"
        "DO_(entry->ParseFromString(data));\n"
        "if ($val_cpp$_IsValid(*entry->mutable_value())) {\n"
        "  (*mutable_$name$())[entry->key()] =\n"
        "      static_cast< $val_cpp$ >(*entry->mutable_value());\n"
        "} else {\n");
    if (HasDescriptorMethods(descriptor_->file(), options_)) {
      format(
          "  mutable_unknown_fields()"
          "->AddLengthDelimited($number$, data);\n");
    } else {
      format(
          "  unknown_fields_stream.WriteVarint32($tag$u);\n"
          "  unknown_fields_stream.WriteVarint32(\n"
          "      static_cast< ::google::protobuf::uint32>(data.size()));\n"
          "  unknown_fields_stream.WriteString(data);\n");
    }
    format("}\n");
  }

  if (key_field->type() == FieldDescriptor::TYPE_STRING) {
    GenerateUtf8CheckCodeForString(
        key_field, options_, true,
        StrCat(key, ".data(), static_cast<int>(", key, ".length()),\n")
            .data(),
        format);
  }
  if (value_field->type() == FieldDescriptor::TYPE_STRING) {
    GenerateUtf8CheckCodeForString(
        value_field, options_, true,
        StrCat(value, ".data(), static_cast<int>(", value,
                     ".length()),\n")
            .data(),
        format);
  }
}

static void GenerateSerializationLoop(const Formatter& format,
                                      bool supports_arenas, bool string_key,
                                      bool string_value, bool to_array,
                                      bool is_deterministic) {
  format("::std::unique_ptr<$map_classname$> entry;\n");
  string ptr;
  if (is_deterministic) {
    format("for (size_type i = 0; i < n; i++) {\n");
    ptr = string_key ? "items[static_cast<ptrdiff_t>(i)]"
                     : "items[static_cast<ptrdiff_t>(i)].second";
  } else {
    format(
        "for (::$proto_ns$::Map< $key_cpp$, $val_cpp$ >::const_iterator\n"
        "    it = this->$name$().begin();\n"
        "    it != this->$name$().end(); ++it) {\n");
    ptr = "it";
  }
  format.Indent();

  format("entry.reset($name$_.New$wrapper$($1$->first, $1$->second));\n", ptr);
  if (to_array) {
    format(
        "target = ::$proto_ns$::internal::WireFormatLite::InternalWrite"
        "$declared_type$NoVirtualToArray($number$, *entry, deterministic, "
        "target);\n");
  } else {
    format(
        "::$proto_ns$::internal::WireFormatLite::Write$stream_writer$($number$,"
        " "
        "*entry, output);\n");
  }

  // If entry is allocated by arena, its desctructor should be avoided.
  if (supports_arenas) {
    format(
        "if (entry->GetArena() != NULL) {\n"
        "  entry.release();\n"
        "}\n");
  }

  if (string_key || string_value) {
    // ptr is either an actual pointer or an iterator, either way we can
    // create a pointer by taking the address after de-referencing it.
    format("Utf8Check::Check(&(*$1$));\n", ptr);
  }

  format.Outdent();
  format("}\n");
}

void MapFieldGenerator::
GenerateSerializeWithCachedSizes(io::Printer* printer) const {
  GenerateSerializeWithCachedSizes(printer, false);
}

void MapFieldGenerator::
GenerateSerializeWithCachedSizesToArray(io::Printer* printer) const {
  GenerateSerializeWithCachedSizes(printer, true);
}

void MapFieldGenerator::GenerateSerializeWithCachedSizes(io::Printer* printer,
                                                         bool to_array) const {
  Formatter format(printer, variables_);
  format("if (!this->$name$().empty()) {\n");
  format.Indent();
  const FieldDescriptor* key_field =
      descriptor_->message_type()->FindFieldByName("key");
  const FieldDescriptor* value_field =
      descriptor_->message_type()->FindFieldByName("value");
  const bool string_key = key_field->type() == FieldDescriptor::TYPE_STRING;
  const bool string_value = value_field->type() == FieldDescriptor::TYPE_STRING;

  format(
      "typedef ::$proto_ns$::Map< $key_cpp$, $val_cpp$ >::const_pointer\n"
      "    ConstPtr;\n");
  if (string_key) {
    format(
        "typedef ConstPtr SortItem;\n"
        "typedef ::$proto_ns$::internal::"
        "CompareByDerefFirst<SortItem> Less;\n");
  } else {
    format(
        "typedef ::$proto_ns$::internal::SortItem< $key_cpp$, ConstPtr > "
        "SortItem;\n"
        "typedef ::$proto_ns$::internal::CompareByFirstField<SortItem> "
        "Less;\n");
  }
  bool utf8_check = string_key || string_value;
  if (utf8_check) {
    format(
        "struct Utf8Check {\n"
        "  static void Check(ConstPtr p) {\n");
    format.Indent();
    format.Indent();
    if (string_key) {
      GenerateUtf8CheckCodeForString(
          key_field, options_, false,
          "p->first.data(), static_cast<int>(p->first.length()),\n", format);
    }
    if (string_value) {
      GenerateUtf8CheckCodeForString(
          value_field, options_, false,
          "p->second.data(), static_cast<int>(p->second.length()),\n", format);
    }
    format.Outdent();
    format.Outdent();
    format(
        "  }\n"
        "};\n");
  }

  format(
      "\n"
      "if ($1$ &&\n"
      "    this->$name$().size() > 1) {\n"
      "  ::std::unique_ptr<SortItem[]> items(\n"
      "      new SortItem[this->$name$().size()]);\n"
      "  typedef ::$proto_ns$::Map< $key_cpp$, $val_cpp$ >::size_type "
      "size_type;\n"
      "  size_type n = 0;\n"
      "  for (::$proto_ns$::Map< $key_cpp$, $val_cpp$ >::const_iterator\n"
      "      it = this->$name$().begin();\n"
      "      it != this->$name$().end(); ++it, ++n) {\n"
      "    items[static_cast<ptrdiff_t>(n)] = SortItem(&*it);\n"
      "  }\n"
      "  ::std::sort(&items[0], &items[static_cast<ptrdiff_t>(n)], Less());\n",
      to_array ? "deterministic" : "output->IsSerializationDeterministic()");
  format.Indent();
  GenerateSerializationLoop(format, SupportsArenas(descriptor_), string_key,
                            string_value, to_array, true);
  format.Outdent();
  format("} else {\n");
  format.Indent();
  GenerateSerializationLoop(format, SupportsArenas(descriptor_), string_key,
                            string_value, to_array, false);
  format.Outdent();
  format("}\n");
  format.Outdent();
  format("}\n");
}

void MapFieldGenerator::
GenerateByteSize(io::Printer* printer) const {
  Formatter format(printer, variables_);
  format(
      "total_size += $tag_size$ *\n"
      "    ::$proto_ns$::internal::FromIntSize(this->$name$_size());\n"
      "{\n"
      "  ::std::unique_ptr<$map_classname$> entry;\n"
      "  for (::$proto_ns$::Map< $key_cpp$, $val_cpp$ >::const_iterator\n"
      "      it = this->$name$().begin();\n"
      "      it != this->$name$().end(); ++it) {\n");

  // If entry is allocated by arena, its desctructor should be avoided.
  if (SupportsArenas(descriptor_)) {
    format(
        "    if (entry.get() != NULL && entry->GetArena() != NULL) {\n"
        "      entry.release();\n"
        "    }\n");
  }

  format(
      "    entry.reset($name$_.New$wrapper$(it->first, it->second));\n"
      "    total_size += ::$proto_ns$::internal::WireFormatLite::\n"
      "        $declared_type$SizeNoVirtual(*entry);\n"
      "  }\n");

  // If entry is allocated by arena, its desctructor should be avoided.
  if (SupportsArenas(descriptor_)) {
    format(
        "  if (entry.get() != NULL && entry->GetArena() != NULL) {\n"
        "    entry.release();\n"
        "  }\n");
  }

  format("}\n");
}

}  // namespace cpp
}  // namespace compiler
}  // namespace protobuf
}  // namespace google