| // Protocol Buffers - Google's data interchange format | |
| // Copyright 2008 Google Inc. All rights reserved. | |
| // | |
| // Use of this source code is governed by a BSD-style | |
| // license that can be found in the LICENSE file or at | |
| // https://developers.google.com/open-source/licenses/bsd | |
| // Author: kenton@google.com (Kenton Varda) | |
| // Based on original Protocol Buffers design by | |
| // Sanjay Ghemawat, Jeff Dean, and others. | |
| // | |
| // Defines the abstract interface implemented by each of the language-specific | |
| // code generators. | |
| // Must be included last. | |
| namespace google { | |
| namespace protobuf { | |
| namespace io { | |
| class ZeroCopyOutputStream; | |
| } | |
| class FileDescriptor; | |
| class GeneratedCodeInfo; | |
| namespace compiler { | |
| class AccessInfoMap; | |
| class Version; | |
| // Defined in this file. | |
| class CodeGenerator; | |
| class GeneratorContext; | |
| // The abstract interface to a class which generates code implementing a | |
| // particular proto file in a particular language. A number of these may | |
| // be registered with CommandLineInterface to support various languages. | |
| class PROTOC_EXPORT CodeGenerator { | |
| public: | |
| CodeGenerator() = default; | |
| CodeGenerator(const CodeGenerator&) = delete; | |
| CodeGenerator& operator=(const CodeGenerator&) = delete; | |
| virtual ~CodeGenerator(); | |
| // Generates code for the given proto file, generating one or more files in | |
| // the given output directory. | |
| // | |
| // A parameter to be passed to the generator can be specified on the command | |
| // line. This is intended to be used to pass generator specific parameters. | |
| // It is empty if no parameter was given. ParseGeneratorParameter (below), | |
| // can be used to accept multiple parameters within the single parameter | |
| // command line flag. | |
| // | |
| // Returns true if successful. Otherwise, sets *error to a description of | |
| // the problem (e.g. "invalid parameter") and returns false. | |
| virtual bool Generate(const FileDescriptor* file, | |
| const std::string& parameter, | |
| GeneratorContext* generator_context, | |
| std::string* error) const = 0; | |
| // Generates code for all given proto files. | |
| // | |
| // WARNING: The canonical code generator design produces one or two output | |
| // files per input .proto file, and we do not wish to encourage alternate | |
| // designs. | |
| // | |
| // A parameter is given as passed on the command line, as in |Generate()| | |
| // above. | |
| // | |
| // Returns true if successful. Otherwise, sets *error to a description of | |
| // the problem (e.g. "invalid parameter") and returns false. | |
| virtual bool GenerateAll(const std::vector<const FileDescriptor*>& files, | |
| const std::string& parameter, | |
| GeneratorContext* generator_context, | |
| std::string* error) const; | |
| // This must be kept in sync with plugin.proto. See that file for | |
| // documentation on each value. | |
| // TODO Use CodeGeneratorResponse.Feature here. | |
| enum Feature { | |
| FEATURE_PROTO3_OPTIONAL = 1, | |
| FEATURE_SUPPORTS_EDITIONS = 2, | |
| }; | |
| // Implement this to indicate what features this code generator supports. | |
| // | |
| // This must be a bitwise OR of values from the Feature enum above (or zero). | |
| virtual uint64_t GetSupportedFeatures() const { return 0; } | |
| // This is no longer used, but this class is part of the opensource protobuf | |
| // library, so it has to remain to keep vtables the same for the current | |
| // version of the library. When protobufs does a api breaking change, the | |
| // method can be removed. | |
| virtual bool HasGenerateAll() const { return true; } | |
| // Returns all the feature extensions used by this generator. This must be in | |
| // the generated pool, meaning that the extensions should be linked into this | |
| // binary. Any generator features not included here will not get properly | |
| // resolved and GetResolvedSourceFeatures will not provide useful values. | |
| virtual std::vector<const FieldDescriptor*> GetFeatureExtensions() const { | |
| return {}; | |
| } | |
| // Returns the minimum edition (inclusive) supported by this generator. Any | |
| // proto files with an edition before this will result in an error. | |
| virtual Edition GetMinimumEdition() const { return Edition::EDITION_UNKNOWN; } | |
| // Returns the maximum edition (inclusive) supported by this generator. Any | |
| // proto files with an edition after this will result in an error. | |
| virtual Edition GetMaximumEdition() const { return Edition::EDITION_UNKNOWN; } | |
| // Builds a default feature set mapping for this generator. | |
| // | |
| // This will use the extensions specified by GetFeatureExtensions(), with the | |
| // supported edition range [GetMinimumEdition(), GetMaximumEdition]. It has | |
| // no side-effects, and code generators only need to call this if they want to | |
| // embed the defaults into the generated code. | |
| absl::StatusOr<FeatureSetDefaults> BuildFeatureSetDefaults() const; | |
| protected: | |
| // Retrieves the resolved source features for a given descriptor. All the | |
| // global features and language features returned by GetFeatureExtensions will | |
| // be fully resolved. These should be used to make any feature-based decisions | |
| // during code generation. | |
| template <typename DescriptorT> | |
| static const FeatureSet& GetResolvedSourceFeatures(const DescriptorT& desc) { | |
| return ::google::protobuf::internal::InternalFeatureHelper::GetFeatures(desc); | |
| } | |
| // Retrieves the unresolved source features for a given descriptor. These | |
| // should be used to validate the original .proto file. These represent the | |
| // original proto files from generated code, but should be stripped of | |
| // source-retention features before sending to a runtime. | |
| template <typename DescriptorT, typename TypeTraitsT, uint8_t field_type, | |
| bool is_packed> | |
| static typename TypeTraitsT::ConstType GetUnresolvedSourceFeatures( | |
| const DescriptorT& descriptor, | |
| const google::protobuf::internal::ExtensionIdentifier< | |
| FeatureSet, TypeTraitsT, field_type, is_packed>& extension) { | |
| return ::google::protobuf::internal::InternalFeatureHelper::GetUnresolvedFeatures( | |
| descriptor, extension); | |
| } | |
| // Retrieves the edition of a built file descriptor. | |
| static Edition GetEdition(const FileDescriptor& file) { | |
| return ::google::protobuf::internal::InternalFeatureHelper::GetEdition(file); | |
| } | |
| }; | |
| constexpr auto MinimumAllowedEdition() { return Edition::EDITION_PROTO2; } | |
| constexpr auto MaximumAllowedEdition() { return Edition::EDITION_2023; } | |
| // CodeGenerators generate one or more files in a given directory. This | |
| // abstract interface represents the directory to which the CodeGenerator is | |
| // to write and other information about the context in which the Generator | |
| // runs. | |
| class PROTOC_EXPORT GeneratorContext { | |
| public: | |
| GeneratorContext() { | |
| } | |
| GeneratorContext(const GeneratorContext&) = delete; | |
| GeneratorContext& operator=(const GeneratorContext&) = delete; | |
| virtual ~GeneratorContext(); | |
| // Opens the given file, truncating it if it exists, and returns a | |
| // ZeroCopyOutputStream that writes to the file. The caller takes ownership | |
| // of the returned object. This method never fails (a dummy stream will be | |
| // returned instead). | |
| // | |
| // The filename given should be relative to the root of the source tree. | |
| // E.g. the C++ generator, when generating code for "foo/bar.proto", will | |
| // generate the files "foo/bar.pb.h" and "foo/bar.pb.cc"; note that | |
| // "foo/" is included in these filenames. The filename is not allowed to | |
| // contain "." or ".." components. | |
| virtual io::ZeroCopyOutputStream* Open(const std::string& filename) = 0; | |
| // Similar to Open() but the output will be appended to the file if exists | |
| virtual io::ZeroCopyOutputStream* OpenForAppend(const std::string& filename); | |
| // Creates a ZeroCopyOutputStream which will insert code into the given file | |
| // at the given insertion point. See plugin.proto (plugin.pb.h) for more | |
| // information on insertion points. The default implementation | |
| // assert-fails -- it exists only for backwards-compatibility. | |
| // | |
| // WARNING: This feature is currently EXPERIMENTAL and is subject to change. | |
| virtual io::ZeroCopyOutputStream* OpenForInsert( | |
| const std::string& filename, const std::string& insertion_point); | |
| // Similar to OpenForInsert, but if `info` is non-empty, will open (or create) | |
| // filename.pb.meta and insert info at the appropriate place with the | |
| // necessary shifts. The default implementation ignores `info`. | |
| // | |
| // WARNING: This feature will be REMOVED in the near future. | |
| virtual io::ZeroCopyOutputStream* OpenForInsertWithGeneratedCodeInfo( | |
| const std::string& filename, const std::string& insertion_point, | |
| const google::protobuf::GeneratedCodeInfo& info); | |
| // Returns a vector of FileDescriptors for all the files being compiled | |
| // in this run. Useful for languages, such as Go, that treat files | |
| // differently when compiled as a set rather than individually. | |
| virtual void ListParsedFiles(std::vector<const FileDescriptor*>* output); | |
| // Retrieves the version number of the protocol compiler associated with | |
| // this GeneratorContext. | |
| virtual void GetCompilerVersion(Version* version) const; | |
| }; | |
| // The type GeneratorContext was once called OutputDirectory. This typedef | |
| // provides backward compatibility. | |
| typedef GeneratorContext OutputDirectory; | |
| // Returns true if the proto path can skip edition check. | |
| PROTOC_EXPORT bool CanSkipEditionCheck(absl::string_view filename); | |
| } // namespace compiler | |
| } // namespace protobuf | |
| } // namespace google | |