intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 896 insertions, 0 deletions

diff --git a/contrib/libs/protoc/src/google/protobuf/compiler/cpp/cpp_helpers.h b/contrib/libs/protoc/src/google/protobuf/compiler/cpp/cpp_helpers.h
new file mode 100644
index 00000000000..1cc9329c86f
--- /dev/null
+++ b/contrib/libs/protoc/src/google/protobuf/compiler/cpp/cpp_helpers.h
@@ -0,0 +1,896 @@
+// Protocol Buffers - Google's data interchange format
+// Copyright 2008 Google Inc.  All rights reserved.
+// https://developers.google.com/protocol-buffers/
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Author: [email protected] (Kenton Varda)
+//  Based on original Protocol Buffers design by
+//  Sanjay Ghemawat, Jeff Dean, and others.
+
+#ifndef GOOGLE_PROTOBUF_COMPILER_CPP_HELPERS_H__
+#define GOOGLE_PROTOBUF_COMPILER_CPP_HELPERS_H__
+
+#include <algorithm>
+#include <cstdint>
+#include <iterator>
+#include <map>
+#include <string>
+
+#include <google/protobuf/compiler/cpp/cpp_options.h>
+#include <google/protobuf/compiler/cpp/cpp_names.h>
+#include <google/protobuf/compiler/scc.h>
+#include <google/protobuf/compiler/code_generator.h>
+#include <google/protobuf/descriptor.pb.h>
+#include <google/protobuf/io/printer.h>
+#include <google/protobuf/descriptor.h>
+#include <google/protobuf/port.h>
+#include <google/protobuf/stubs/strutil.h>
+
+// Must be included last.
+#include <google/protobuf/port_def.inc>
+
+namespace google {
+namespace protobuf {
+namespace compiler {
+namespace cpp {
+
+inline TProtoStringType ProtobufNamespace(const Options& /* options */) {
+  return "PROTOBUF_NAMESPACE_ID";
+}
+
+inline TProtoStringType MacroPrefix(const Options& options) {
+  return options.opensource_runtime ? "GOOGLE_PROTOBUF" : "GOOGLE_PROTOBUF";
+}
+
+inline TProtoStringType DeprecatedAttribute(const Options& /* options */,
+                                       const FieldDescriptor* d) {
+  return d->options().deprecated() ? "PROTOBUF_DEPRECATED " : "";
+}
+
+inline TProtoStringType DeprecatedAttribute(const Options& /* options */,
+                                       const EnumValueDescriptor* d) {
+  return d->options().deprecated() ? "PROTOBUF_DEPRECATED_ENUM " : "";
+}
+
+// Commonly-used separator comments.  Thick is a line of '=', thin is a line
+// of '-'.
+extern const char kThickSeparator[];
+extern const char kThinSeparator[];
+
+void SetCommonVars(const Options& options,
+                   std::map<TProtoStringType, TProtoStringType>* variables);
+
+void SetUnknownFieldsVariable(const Descriptor* descriptor,
+                              const Options& options,
+                              std::map<TProtoStringType, TProtoStringType>* variables);
+
+bool GetBootstrapBasename(const Options& options, const TProtoStringType& basename,
+                          TProtoStringType* bootstrap_basename);
+bool MaybeBootstrap(const Options& options, GeneratorContext* generator_context,
+                    bool bootstrap_flag, TProtoStringType* basename);
+bool IsBootstrapProto(const Options& options, const FileDescriptor* file);
+
+// Name space of the proto file. This namespace is such that the string
+// "<namespace>::some_name" is the correct fully qualified namespace.
+// This means if the package is empty the namespace is "", and otherwise
+// the namespace is "::foo::bar::...::baz" without trailing semi-colons.
+TProtoStringType Namespace(const FileDescriptor* d, const Options& options);
+TProtoStringType Namespace(const Descriptor* d, const Options& options);
+TProtoStringType Namespace(const FieldDescriptor* d, const Options& options);
+TProtoStringType Namespace(const EnumDescriptor* d, const Options& options);
+
+// Returns true if it's safe to reset "field" to zero.
+bool CanInitializeByZeroing(const FieldDescriptor* field);
+
+TProtoStringType ClassName(const Descriptor* descriptor);
+TProtoStringType ClassName(const EnumDescriptor* enum_descriptor);
+
+TProtoStringType QualifiedClassName(const Descriptor* d, const Options& options);
+TProtoStringType QualifiedClassName(const EnumDescriptor* d, const Options& options);
+
+TProtoStringType QualifiedClassName(const Descriptor* d);
+TProtoStringType QualifiedClassName(const EnumDescriptor* d);
+
+// DEPRECATED just use ClassName or QualifiedClassName, a boolean is very
+// unreadable at the callsite.
+// Returns the non-nested type name for the given type.  If "qualified" is
+// true, prefix the type with the full namespace.  For example, if you had:
+//   package foo.bar;
+//   message Baz { message Qux {} }
+// Then the qualified ClassName for Qux would be:
+//   ::foo::bar::Baz_Qux
+// While the non-qualified version would be:
+//   Baz_Qux
+inline TProtoStringType ClassName(const Descriptor* descriptor, bool qualified) {
+  return qualified ? QualifiedClassName(descriptor, Options())
+                   : ClassName(descriptor);
+}
+
+inline TProtoStringType ClassName(const EnumDescriptor* descriptor, bool qualified) {
+  return qualified ? QualifiedClassName(descriptor, Options())
+                   : ClassName(descriptor);
+}
+
+// Returns the extension name prefixed with the class name if nested but without
+// the package name.
+TProtoStringType ExtensionName(const FieldDescriptor* d);
+
+TProtoStringType QualifiedExtensionName(const FieldDescriptor* d,
+                                   const Options& options);
+TProtoStringType QualifiedExtensionName(const FieldDescriptor* d);
+
+// Type name of default instance.
+TProtoStringType DefaultInstanceType(const Descriptor* descriptor,
+                                const Options& options);
+
+// Non-qualified name of the default_instance of this message.
+TProtoStringType DefaultInstanceName(const Descriptor* descriptor,
+                                const Options& options);
+
+// Non-qualified name of the default instance pointer. This is used only for
+// implicit weak fields, where we need an extra indirection.
+TProtoStringType DefaultInstancePtr(const Descriptor* descriptor,
+                               const Options& options);
+
+// Fully qualified name of the default_instance of this message.
+TProtoStringType QualifiedDefaultInstanceName(const Descriptor* descriptor,
+                                         const Options& options);
+
+// Fully qualified name of the default instance pointer.
+TProtoStringType QualifiedDefaultInstancePtr(const Descriptor* descriptor,
+                                        const Options& options);
+
+// DescriptorTable variable name.
+TProtoStringType DescriptorTableName(const FileDescriptor* file,
+                                const Options& options);
+
+// When declaring symbol externs from another file, this macro will supply the
+// dllexport needed for the target file, if any.
+TProtoStringType FileDllExport(const FileDescriptor* file, const Options& options);
+
+// Name of the base class: google::protobuf::Message or google::protobuf::MessageLite.
+TProtoStringType SuperClassName(const Descriptor* descriptor,
+                           const Options& options);
+
+// Adds an underscore if necessary to prevent conflicting with a keyword.
+TProtoStringType ResolveKeyword(const TProtoStringType& name);
+
+// Get the (unqualified) name that should be used for this field in C++ code.
+// The name is coerced to lower-case to emulate proto1 behavior.  People
+// should be using lowercase-with-underscores style for proto field names
+// anyway, so normally this just returns field->name().
+TProtoStringType FieldName(const FieldDescriptor* field);
+
+// Returns an estimate of the compiler's alignment for the field.  This
+// can't guarantee to be correct because the generated code could be compiled on
+// different systems with different alignment rules.  The estimates below assume
+// 64-bit pointers.
+int EstimateAlignmentSize(const FieldDescriptor* field);
+
+// Get the unqualified name that should be used for a field's field
+// number constant.
+TProtoStringType FieldConstantName(const FieldDescriptor* field);
+
+// Returns the scope where the field was defined (for extensions, this is
+// different from the message type to which the field applies).
+inline const Descriptor* FieldScope(const FieldDescriptor* field) {
+  return field->is_extension() ? field->extension_scope()
+                               : field->containing_type();
+}
+
+// Returns the fully-qualified type name field->message_type().  Usually this
+// is just ClassName(field->message_type(), true);
+TProtoStringType FieldMessageTypeName(const FieldDescriptor* field,
+                                 const Options& options);
+
+// Get the C++ type name for a primitive type (e.g. "double", "::google::protobuf::int32", etc.).
+const char* PrimitiveTypeName(FieldDescriptor::CppType type);
+TProtoStringType PrimitiveTypeName(const Options& options,
+                              FieldDescriptor::CppType type);
+
+// Get the declared type name in CamelCase format, as is used e.g. for the
+// methods of WireFormat.  For example, TYPE_INT32 becomes "Int32".
+const char* DeclaredTypeMethodName(FieldDescriptor::Type type);
+
+// Return the code that evaluates to the number when compiled.
+TProtoStringType Int32ToString(int number);
+
+// Get code that evaluates to the field's default value.
+TProtoStringType DefaultValue(const Options& options, const FieldDescriptor* field);
+
+// Compatibility function for callers outside proto2.
+TProtoStringType DefaultValue(const FieldDescriptor* field);
+
+// Convert a file name into a valid identifier.
+TProtoStringType FilenameIdentifier(const TProtoStringType& filename);
+
+// For each .proto file generates a unique name. To prevent collisions of
+// symbols in the global namespace
+TProtoStringType UniqueName(const TProtoStringType& name, const TProtoStringType& filename,
+                       const Options& options);
+inline TProtoStringType UniqueName(const TProtoStringType& name, const FileDescriptor* d,
+                              const Options& options) {
+  return UniqueName(name, d->name(), options);
+}
+inline TProtoStringType UniqueName(const TProtoStringType& name, const Descriptor* d,
+                              const Options& options) {
+  return UniqueName(name, d->file(), options);
+}
+inline TProtoStringType UniqueName(const TProtoStringType& name, const EnumDescriptor* d,
+                              const Options& options) {
+  return UniqueName(name, d->file(), options);
+}
+inline TProtoStringType UniqueName(const TProtoStringType& name,
+                              const ServiceDescriptor* d,
+                              const Options& options) {
+  return UniqueName(name, d->file(), options);
+}
+
+// Versions for call sites that only support the internal runtime (like proto1
+// support).
+inline Options InternalRuntimeOptions() {
+  Options options;
+  options.opensource_runtime = false;
+  return options;
+}
+inline TProtoStringType UniqueName(const TProtoStringType& name,
+                              const TProtoStringType& filename) {
+  return UniqueName(name, filename, InternalRuntimeOptions());
+}
+inline TProtoStringType UniqueName(const TProtoStringType& name,
+                              const FileDescriptor* d) {
+  return UniqueName(name, d->name(), InternalRuntimeOptions());
+}
+inline TProtoStringType UniqueName(const TProtoStringType& name, const Descriptor* d) {
+  return UniqueName(name, d->file(), InternalRuntimeOptions());
+}
+inline TProtoStringType UniqueName(const TProtoStringType& name,
+                              const EnumDescriptor* d) {
+  return UniqueName(name, d->file(), InternalRuntimeOptions());
+}
+inline TProtoStringType UniqueName(const TProtoStringType& name,
+                              const ServiceDescriptor* d) {
+  return UniqueName(name, d->file(), InternalRuntimeOptions());
+}
+
+// Return the qualified C++ name for a file level symbol.
+TProtoStringType QualifiedFileLevelSymbol(const FileDescriptor* file,
+                                     const TProtoStringType& name,
+                                     const Options& options);
+
+// Escape C++ trigraphs by escaping question marks to \?
+TProtoStringType EscapeTrigraphs(const TProtoStringType& to_escape);
+
+// Escaped function name to eliminate naming conflict.
+TProtoStringType SafeFunctionName(const Descriptor* descriptor,
+                             const FieldDescriptor* field,
+                             const TProtoStringType& prefix);
+
+// Returns true if generated messages have public unknown fields accessors
+inline bool PublicUnknownFieldsAccessors(const Descriptor* message) {
+  return message->file()->syntax() != FileDescriptor::SYNTAX_PROTO3;
+}
+
+// Returns the optimize mode for <file>, respecting <options.enforce_lite>.
+FileOptions_OptimizeMode GetOptimizeFor(const FileDescriptor* file,
+                                        const Options& options);
+
+// Determines whether unknown fields will be stored in an UnknownFieldSet or
+// a string.
+inline bool UseUnknownFieldSet(const FileDescriptor* file,
+                               const Options& options) {
+  return GetOptimizeFor(file, options) != FileOptions::LITE_RUNTIME;
+}
+
+inline bool IsWeak(const FieldDescriptor* field, const Options& options) {
+  if (field->options().weak()) {
+    GOOGLE_CHECK(!options.opensource_runtime);
+    return true;
+  }
+  return false;
+}
+
+// For a string field, returns the effective ctype.  If the actual ctype is
+// not supported, returns the default of STRING.
+FieldOptions::CType EffectiveStringCType(const FieldDescriptor* field,
+                                         const Options& options);
+
+inline bool IsCord(const FieldDescriptor* field, const Options& options) {
+  return field->cpp_type() == FieldDescriptor::CPPTYPE_STRING &&
+         EffectiveStringCType(field, options) == FieldOptions::CORD;
+}
+
+inline bool IsStringPiece(const FieldDescriptor* field,
+                          const Options& options) {
+  return field->cpp_type() == FieldDescriptor::CPPTYPE_STRING &&
+         EffectiveStringCType(field, options) == FieldOptions::STRING_PIECE;
+}
+
+class MessageSCCAnalyzer;
+
+// Does the given FileDescriptor use lazy fields?
+bool HasLazyFields(const FileDescriptor* file, const Options& options,
+                   MessageSCCAnalyzer* scc_analyzer);
+
+// Is the given field a supported lazy field?
+bool IsLazy(const FieldDescriptor* field, const Options& options,
+            MessageSCCAnalyzer* scc_analyzer);
+
+inline bool IsLazilyVerifiedLazy(const FieldDescriptor* field,
+                                 const Options& options) {
+  return field->options().lazy() && !field->is_repeated() &&
+         field->type() == FieldDescriptor::TYPE_MESSAGE &&
+         GetOptimizeFor(field->file(), options) != FileOptions::LITE_RUNTIME &&
+         !options.opensource_runtime;
+}
+
+inline bool IsEagerlyVerifiedLazy(const FieldDescriptor* field,
+                                  const Options& options,
+                                  MessageSCCAnalyzer* scc_analyzer) {
+  return IsLazy(field, options, scc_analyzer) && !field->options().lazy();
+}
+
+inline bool IsFieldUsed(const FieldDescriptor* /* field */,
+                        const Options& /* options */) {
+  return true;
+}
+
+// Returns true if "field" is stripped.
+inline bool IsFieldStripped(const FieldDescriptor* /*field*/,
+                            const Options& /*options*/) {
+  return false;
+}
+
+// Does the file contain any definitions that need extension_set.h?
+bool HasExtensionsOrExtendableMessage(const FileDescriptor* file);
+
+// Does the file have any repeated fields, necessitating the file to include
+// repeated_field.h? This does not include repeated extensions, since those are
+// all stored internally in an ExtensionSet, not a separate RepeatedField*.
+bool HasRepeatedFields(const FileDescriptor* file);
+
+// Does the file have any string/bytes fields with ctype=STRING_PIECE? This
+// does not include extensions, since ctype is ignored for extensions.
+bool HasStringPieceFields(const FileDescriptor* file, const Options& options);
+
+// Does the file have any string/bytes fields with ctype=CORD? This does not
+// include extensions, since ctype is ignored for extensions.
+bool HasCordFields(const FileDescriptor* file, const Options& options);
+
+// Does the file have any map fields, necessitating the file to include
+// map_field_inl.h and map.h.
+bool HasMapFields(const FileDescriptor* file);
+
+// Does this file have any enum type definitions?
+bool HasEnumDefinitions(const FileDescriptor* file);
+
+// Does this file have generated parsing, serialization, and other
+// standard methods for which reflection-based fallback implementations exist?
+inline bool HasGeneratedMethods(const FileDescriptor* file,
+                                const Options& options) {
+  return GetOptimizeFor(file, options) != FileOptions::CODE_SIZE;
+}
+
+// Do message classes in this file have descriptor and reflection methods?
+inline bool HasDescriptorMethods(const FileDescriptor* file,
+                                 const Options& options) {
+  return GetOptimizeFor(file, options) != FileOptions::LITE_RUNTIME;
+}
+
+// Should we generate generic services for this file?
+inline bool HasGenericServices(const FileDescriptor* file,
+                               const Options& options) {
+  return file->service_count() > 0 &&
+         GetOptimizeFor(file, options) != FileOptions::LITE_RUNTIME &&
+         file->options().cc_generic_services();
+}
+
+inline bool IsProto2MessageSet(const Descriptor* descriptor,
+                               const Options& options) {
+  return !options.opensource_runtime &&
+         options.enforce_mode != EnforceOptimizeMode::kLiteRuntime &&
+         !options.lite_implicit_weak_fields &&
+         descriptor->options().message_set_wire_format() &&
+         descriptor->full_name() == "google.protobuf.bridge.MessageSet";
+}
+
+inline bool IsMapEntryMessage(const Descriptor* descriptor) {
+  return descriptor->options().map_entry();
+}
+
+// Returns true if the field's CPPTYPE is string or message.
+bool IsStringOrMessage(const FieldDescriptor* field);
+
+TProtoStringType UnderscoresToCamelCase(const TProtoStringType& input,
+                                   bool cap_next_letter);
+
+inline bool IsProto3(const FileDescriptor* file) {
+  return file->syntax() == FileDescriptor::SYNTAX_PROTO3;
+}
+
+inline bool HasHasbit(const FieldDescriptor* field) {
+  // This predicate includes proto3 message fields only if they have "optional".
+  //   Foo submsg1 = 1;           // HasHasbit() == false
+  //   optional Foo submsg2 = 2;  // HasHasbit() == true
+  // This is slightly odd, as adding "optional" to a singular proto3 field does
+  // not change the semantics or API. However whenever any field in a message
+  // has a hasbit, it forces reflection to include hasbit offsets for *all*
+  // fields, even if almost all of them are set to -1 (no hasbit). So to avoid
+  // causing a sudden size regression for ~all proto3 messages, we give proto3
+  // message fields a hasbit only if "optional" is present. If the user is
+  // explicitly writing "optional", it is likely they are writing it on
+  // primitive fields also.
+  return (field->has_optional_keyword() || field->is_required()) &&
+         !field->options().weak();
+}
+
+// Returns true if 'enum' semantics are such that unknown values are preserved
+// in the enum field itself, rather than going to the UnknownFieldSet.
+inline bool HasPreservingUnknownEnumSemantics(const FieldDescriptor* field) {
+  return field->file()->syntax() == FileDescriptor::SYNTAX_PROTO3;
+}
+
+inline bool IsCrossFileMessage(const FieldDescriptor* field) {
+  return field->type() == FieldDescriptor::TYPE_MESSAGE &&
+         field->message_type()->file() != field->file();
+}
+
+inline TProtoStringType MakeDefaultName(const FieldDescriptor* field) {
+  return "_i_give_permission_to_break_this_code_default_" + FieldName(field) +
+         "_";
+}
+
+bool IsAnyMessage(const FileDescriptor* descriptor, const Options& options);
+bool IsAnyMessage(const Descriptor* descriptor, const Options& options);
+
+bool IsWellKnownMessage(const FileDescriptor* descriptor);
+
+inline TProtoStringType IncludeGuard(const FileDescriptor* file, bool pb_h,
+                                const Options& options) {
+  // If we are generating a .pb.h file and the proto_h option is enabled, then
+  // the .pb.h gets an extra suffix.
+  TProtoStringType filename_identifier = FilenameIdentifier(
+      file->name() + (pb_h && options.proto_h ? ".pb.h" : ""));
+
+  if (IsWellKnownMessage(file)) {
+    // For well-known messages we need third_party/protobuf and net/proto2 to
+    // have distinct include guards, because some source files include both and
+    // both need to be defined (the third_party copies will be in the
+    // google::protobuf_opensource namespace).
+    return MacroPrefix(options) + "_INCLUDED_" + filename_identifier;
+  } else {
+    // Ideally this case would use distinct include guards for opensource and
+    // google3 protos also.  (The behavior of "first #included wins" is not
+    // ideal).  But unfortunately some legacy code includes both and depends on
+    // the identical include guards to avoid compile errors.
+    //
+    // We should clean this up so that this case can be removed.
+    return "GOOGLE_PROTOBUF_INCLUDED_" + filename_identifier;
+  }
+}
+
+// Returns the OptimizeMode for this file, furthermore it updates a status
+// bool if has_opt_codesize_extension is non-null. If this status bool is true
+// it means this file contains an extension that itself is defined as
+// optimized_for = CODE_SIZE.
+FileOptions_OptimizeMode GetOptimizeFor(const FileDescriptor* file,
+                                        const Options& options,
+                                        bool* has_opt_codesize_extension);
+inline FileOptions_OptimizeMode GetOptimizeFor(const FileDescriptor* file,
+                                               const Options& options) {
+  return GetOptimizeFor(file, options, nullptr);
+}
+inline bool NeedsEagerDescriptorAssignment(const FileDescriptor* file,
+                                           const Options& options) {
+  bool has_opt_codesize_extension;
+  if (GetOptimizeFor(file, options, &has_opt_codesize_extension) ==
+          FileOptions::CODE_SIZE &&
+      has_opt_codesize_extension) {
+    // If this filedescriptor contains an extension from another file which
+    // is optimized_for = CODE_SIZE. We need to be careful in the ordering so
+    // we eagerly build the descriptors in the dependencies before building
+    // the descriptors of this file.
+    return true;
+  } else {
+    // If we have a generated code based parser we never need eager
+    // initialization of descriptors of our deps.
+    return false;
+  }
+}
+
+// This orders the messages in a .pb.cc as it's outputted by file.cc
+void FlattenMessagesInFile(const FileDescriptor* file,
+                           std::vector<const Descriptor*>* result);
+inline std::vector<const Descriptor*> FlattenMessagesInFile(
+    const FileDescriptor* file) {
+  std::vector<const Descriptor*> result;
+  FlattenMessagesInFile(file, &result);
+  return result;
+}
+
+bool HasWeakFields(const Descriptor* desc, const Options& options);
+bool HasWeakFields(const FileDescriptor* desc, const Options& options);
+
+// Returns true if the "required" restriction check should be ignored for the
+// given field.
+inline static bool ShouldIgnoreRequiredFieldCheck(const FieldDescriptor* field,
+                                                  const Options& options) {
+  // Do not check "required" for lazily verified lazy fields.
+  return IsLazilyVerifiedLazy(field, options);
+}
+
+struct MessageAnalysis {
+  bool is_recursive;
+  bool contains_cord;
+  bool contains_extension;
+  bool contains_required;
+  bool contains_weak;  // Implicit weak as well.
+};
+
+// This class is used in FileGenerator, to ensure linear instead of
+// quadratic performance, if we do this per message we would get O(V*(V+E)).
+// Logically this is just only used in message.cc, but in the header for
+// FileGenerator to help share it.
+class PROTOC_EXPORT MessageSCCAnalyzer {
+ public:
+  explicit MessageSCCAnalyzer(const Options& options) : options_(options) {}
+
+  MessageAnalysis GetSCCAnalysis(const SCC* scc);
+
+  bool HasRequiredFields(const Descriptor* descriptor) {
+    MessageAnalysis result = GetSCCAnalysis(GetSCC(descriptor));
+    return result.contains_required || result.contains_extension;
+  }
+  bool HasWeakField(const Descriptor* descriptor) {
+    MessageAnalysis result = GetSCCAnalysis(GetSCC(descriptor));
+    return result.contains_weak;
+  }
+  const SCC* GetSCC(const Descriptor* descriptor) {
+    return analyzer_.GetSCC(descriptor);
+  }
+
+ private:
+  struct DepsGenerator {
+    std::vector<const Descriptor*> operator()(const Descriptor* desc) const {
+      std::vector<const Descriptor*> deps;
+      for (int i = 0; i < desc->field_count(); i++) {
+        if (desc->field(i)->message_type()) {
+          deps.push_back(desc->field(i)->message_type());
+        }
+      }
+      return deps;
+    }
+  };
+  SCCAnalyzer<DepsGenerator> analyzer_;
+  Options options_;
+  std::map<const SCC*, MessageAnalysis> analysis_cache_;
+};
+
+void ListAllFields(const Descriptor* d,
+                   std::vector<const FieldDescriptor*>* fields);
+void ListAllFields(const FileDescriptor* d,
+                   std::vector<const FieldDescriptor*>* fields);
+
+template <class T>
+void ForEachField(const Descriptor* d, T&& func) {
+  for (int i = 0; i < d->nested_type_count(); i++) {
+    ForEachField(d->nested_type(i), std::forward<T&&>(func));
+  }
+  for (int i = 0; i < d->extension_count(); i++) {
+    func(d->extension(i));
+  }
+  for (int i = 0; i < d->field_count(); i++) {
+    func(d->field(i));
+  }
+}
+
+template <class T>
+void ForEachField(const FileDescriptor* d, T&& func) {
+  for (int i = 0; i < d->message_type_count(); i++) {
+    ForEachField(d->message_type(i), std::forward<T&&>(func));
+  }
+  for (int i = 0; i < d->extension_count(); i++) {
+    func(d->extension(i));
+  }
+}
+
+void ListAllTypesForServices(const FileDescriptor* fd,
+                             std::vector<const Descriptor*>* types);
+
+// Indicates whether we should use implicit weak fields for this file.
+bool UsingImplicitWeakFields(const FileDescriptor* file,
+                             const Options& options);
+
+// Indicates whether to treat this field as implicitly weak.
+bool IsImplicitWeakField(const FieldDescriptor* field, const Options& options,
+                         MessageSCCAnalyzer* scc_analyzer);
+
+// Formatter is a functor class which acts as a closure around printer and
+// the variable map. It's much like printer->Print except it supports both named
+// variables that are substituted using a key value map and direct arguments. In
+// the format string $1$, $2$, etc... are substituted for the first, second, ...
+// direct argument respectively in the format call, it accepts both strings and
+// integers. The implementation verifies all arguments are used and are "first"
+// used in order of appearance in the argument list. For example,
+//
+// Format("return array[$1$];", 3) -> "return array[3];"
+// Format("array[$2$] = $1$;", "Bla", 3) -> FATAL error (wrong order)
+// Format("array[$1$] = $2$;", 3, "Bla") -> "array[3] = Bla;"
+//
+// The arguments can be used more than once like
+//
+// Format("array[$1$] = $2$;  // Index = $1$", 3, "Bla") ->
+//        "array[3] = Bla;  // Index = 3"
+//
+// If you use more arguments use the following style to help the reader,
+//
+// Format("int $1$() {\n"
+//        "  array[$2$] = $3$;\n"
+//        "  return $4$;"
+//        "}\n",
+//        funname, // 1
+//        idx,  // 2
+//        varname,  // 3
+//        retval);  // 4
+//
+// but consider using named variables. Named variables like $foo$, with some
+// identifier foo, are looked up in the map. One additional feature is that
+// spaces are accepted between the '$' delimiters, $ foo$ will
+// substiture to " bar" if foo stands for "bar", but in case it's empty
+// will substitute to "". Hence, for example,
+//
+// Format(vars, "$dllexport $void fun();") -> "void fun();"
+//                                            "__declspec(export) void fun();"
+//
+// which is convenient to prevent double, leading or trailing spaces.
+class PROTOC_EXPORT Formatter {
+ public:
+  explicit Formatter(io::Printer* printer) : printer_(printer) {}
+  Formatter(io::Printer* printer,
+            const std::map<TProtoStringType, TProtoStringType>& vars)
+      : printer_(printer), vars_(vars) {}
+
+  template <typename T>
+  void Set(const TProtoStringType& key, const T& value) {
+    vars_[key] = ToString(value);
+  }
+
+  void AddMap(const std::map<TProtoStringType, TProtoStringType>& vars) {
+    for (const auto& keyval : vars) vars_[keyval.first] = keyval.second;
+  }
+
+  template <typename... Args>
+  void operator()(const char* format, const Args&... args) const {
+    printer_->FormatInternal({ToString(args)...}, vars_, format);
+  }
+
+  void Indent() const { printer_->Indent(); }
+  void Outdent() const { printer_->Outdent(); }
+  io::Printer* printer() const { return printer_; }
+
+  class PROTOC_EXPORT SaveState {
+   public:
+    explicit SaveState(Formatter* format)
+        : format_(format), vars_(format->vars_) {}
+    ~SaveState() { format_->vars_.swap(vars_); }
+
+   private:
+    Formatter* format_;
+    std::map<TProtoStringType, TProtoStringType> vars_;
+  };
+
+ private:
+  io::Printer* printer_;
+  std::map<TProtoStringType, TProtoStringType> vars_;
+
+  // Convenience overloads to accept different types as arguments.
+  static TProtoStringType ToString(const TProtoStringType& s) { return s; }
+  template <typename I, typename = typename std::enable_if<
+                            std::is_integral<I>::value>::type>
+  static TProtoStringType ToString(I x) {
+    return StrCat(x);
+  }
+  static TProtoStringType ToString(strings::Hex x) { return StrCat(x); }
+  static TProtoStringType ToString(const FieldDescriptor* d) { return Payload(d); }
+  static TProtoStringType ToString(const Descriptor* d) { return Payload(d); }
+  static TProtoStringType ToString(const EnumDescriptor* d) { return Payload(d); }
+  static TProtoStringType ToString(const EnumValueDescriptor* d) {
+    return Payload(d);
+  }
+  static TProtoStringType ToString(const OneofDescriptor* d) { return Payload(d); }
+
+  template <typename Descriptor>
+  static TProtoStringType Payload(const Descriptor* descriptor) {
+    std::vector<int> path;
+    descriptor->GetLocationPath(&path);
+    GeneratedCodeInfo::Annotation annotation;
+    for (int index : path) {
+      annotation.add_path(index);
+    }
+    annotation.set_source_file(descriptor->file()->name());
+    return annotation.SerializeAsString();
+  }
+};
+
+template <class T>
+void PrintFieldComment(const Formatter& format, const T* field) {
+  // Print the field's (or oneof's) proto-syntax definition as a comment.
+  // We don't want to print group bodies so we cut off after the first
+  // line.
+  DebugStringOptions options;
+  options.elide_group_body = true;
+  options.elide_oneof_body = true;
+  TProtoStringType def = field->DebugStringWithOptions(options);
+  format("// $1$\n", def.substr(0, def.find_first_of('\n')));
+}
+
+class PROTOC_EXPORT NamespaceOpener {
+ public:
+  explicit NamespaceOpener(const Formatter& format)
+      : printer_(format.printer()) {}
+  NamespaceOpener(const TProtoStringType& name, const Formatter& format)
+      : NamespaceOpener(format) {
+    ChangeTo(name);
+  }
+  ~NamespaceOpener() { ChangeTo(""); }
+
+  void ChangeTo(const TProtoStringType& name) {
+    std::vector<TProtoStringType> new_stack_ =
+        Split(name, "::", true);
+    size_t len = std::min(name_stack_.size(), new_stack_.size());
+    size_t common_idx = 0;
+    while (common_idx < len) {
+      if (name_stack_[common_idx] != new_stack_[common_idx]) break;
+      common_idx++;
+    }
+    for (auto it = name_stack_.crbegin();
+         it != name_stack_.crend() - common_idx; ++it) {
+      if (*it == "PROTOBUF_NAMESPACE_ID") {
+        printer_->Print("PROTOBUF_NAMESPACE_CLOSE\n");
+      } else {
+        printer_->Print("}  // namespace $ns$\n", "ns", *it);
+      }
+    }
+    name_stack_.swap(new_stack_);
+    for (size_t i = common_idx; i < name_stack_.size(); ++i) {
+      if (name_stack_[i] == "PROTOBUF_NAMESPACE_ID") {
+        printer_->Print("PROTOBUF_NAMESPACE_OPEN\n");
+      } else {
+        printer_->Print("namespace $ns$ {\n", "ns", name_stack_[i]);
+      }
+    }
+  }
+
+ private:
+  io::Printer* printer_;
+  std::vector<TProtoStringType> name_stack_;
+};
+
+enum class Utf8CheckMode {
+  kStrict = 0,  // Parsing will fail if non UTF-8 data is in string fields.
+  kVerify = 1,  // Only log an error but parsing will succeed.
+  kNone = 2,    // No UTF-8 check.
+};
+
+Utf8CheckMode GetUtf8CheckMode(const FieldDescriptor* field,
+                               const Options& options);
+
+void GenerateUtf8CheckCodeForString(const FieldDescriptor* field,
+                                    const Options& options, bool for_parse,
+                                    const char* parameters,
+                                    const Formatter& format);
+
+void GenerateUtf8CheckCodeForCord(const FieldDescriptor* field,
+                                  const Options& options, bool for_parse,
+                                  const char* parameters,
+                                  const Formatter& format);
+
+template <typename T>
+struct FieldRangeImpl {
+  struct Iterator {
+    using iterator_category = std::forward_iterator_tag;
+    using value_type = const FieldDescriptor*;
+    using difference_type = int;
+
+    value_type operator*() { return descriptor->field(idx); }
+
+    friend bool operator==(const Iterator& a, const Iterator& b) {
+      GOOGLE_DCHECK(a.descriptor == b.descriptor);
+      return a.idx == b.idx;
+    }
+    friend bool operator!=(const Iterator& a, const Iterator& b) {
+      return !(a == b);
+    }
+
+    Iterator& operator++() {
+      idx++;
+      return *this;
+    }
+
+    int idx;
+    const T* descriptor;
+  };
+
+  Iterator begin() const { return {0, descriptor}; }
+  Iterator end() const { return {descriptor->field_count(), descriptor}; }
+
+  const T* descriptor;
+};
+
+template <typename T>
+FieldRangeImpl<T> FieldRange(const T* desc) {
+  return {desc};
+}
+
+struct OneOfRangeImpl {
+  struct Iterator {
+    using iterator_category = std::forward_iterator_tag;
+    using value_type = const OneofDescriptor*;
+    using difference_type = int;
+
+    value_type operator*() { return descriptor->oneof_decl(idx); }
+
+    friend bool operator==(const Iterator& a, const Iterator& b) {
+      GOOGLE_DCHECK(a.descriptor == b.descriptor);
+      return a.idx == b.idx;
+    }
+    friend bool operator!=(const Iterator& a, const Iterator& b) {
+      return !(a == b);
+    }
+
+    Iterator& operator++() {
+      idx++;
+      return *this;
+    }
+
+    int idx;
+    const Descriptor* descriptor;
+  };
+
+  Iterator begin() const { return {0, descriptor}; }
+  Iterator end() const {
+    return {descriptor->real_oneof_decl_count(), descriptor};
+  }
+
+  const Descriptor* descriptor;
+};
+
+inline OneOfRangeImpl OneOfRange(const Descriptor* desc) { return {desc}; }
+
+PROTOC_EXPORT TProtoStringType StripProto(const TProtoStringType& filename);
+
+inline bool EnableMessageOwnedArena(const Descriptor* /* desc */ ) { return false; }
+
+}  // namespace cpp
+}  // namespace compiler
+}  // namespace protobuf
+}  // namespace google
+
+#include <google/protobuf/port_undef.inc>
+
+#endif  // GOOGLE_PROTOBUF_COMPILER_CPP_HELPERS_H__