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// Protocol Buffers - Google's data interchange format
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// Copyright 2023 Google LLC. All rights reserved.
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//
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file or at
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// https://developers.google.com/open-source/licenses/bsd
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#include "google/protobuf/compiler/hpb/gen_messages.h"
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#include <cstddef>
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#include <string>
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#include <vector>
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#include "google/protobuf/descriptor.pb.h"
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#include "absl/strings/ascii.h"
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#include "absl/strings/str_cat.h"
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#include "absl/strings/string_view.h"
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#include "google/protobuf/compiler/hpb/gen_accessors.h"
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#include "google/protobuf/compiler/hpb/gen_enums.h"
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#include "google/protobuf/compiler/hpb/gen_extensions.h"
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#include "google/protobuf/compiler/hpb/gen_utils.h"
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#include "google/protobuf/compiler/hpb/names.h"
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#include "google/protobuf/compiler/hpb/output.h"
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#include "google/protobuf/descriptor.h"
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#include "upb_generator/common.h"
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#include "upb_generator/file_layout.h"
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namespace google::protobuf::hpb_generator {
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namespace protobuf = ::proto2;
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void WriteModelAccessDeclaration(const protobuf::Descriptor* descriptor,
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Output& output);
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void WriteModelPublicDeclaration(
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const protobuf::Descriptor* descriptor,
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const std::vector<const protobuf::FieldDescriptor*>& file_exts,
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const std::vector<const protobuf::EnumDescriptor*>& file_enums,
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Output& output);
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void WriteExtensionIdentifiersInClassHeader(
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const protobuf::Descriptor* message,
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const std::vector<const protobuf::FieldDescriptor*>& file_exts,
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Output& output);
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void WriteModelProxyDeclaration(const protobuf::Descriptor* descriptor,
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Output& output);
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void WriteModelCProxyDeclaration(const protobuf::Descriptor* descriptor,
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Output& output);
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void WriteInternalForwardDeclarationsInHeader(
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const protobuf::Descriptor* message, Output& output);
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void WriteDefaultInstanceHeader(const protobuf::Descriptor* message,
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Output& output);
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void WriteExtensionIdentifiersImplementation(
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const protobuf::Descriptor* message,
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const std::vector<const protobuf::FieldDescriptor*>& file_exts,
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Output& output);
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void WriteUsingEnumsInHeader(
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const protobuf::Descriptor* message,
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const std::vector<const protobuf::EnumDescriptor*>& file_enums,
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Output& output);
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// Writes message class declarations into .upb.proto.h.
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//
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// For each proto Foo, FooAccess and FooProxy/FooCProxy are generated
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// that are exposed to users as Foo , Ptr<Foo> and Ptr<const Foo>.
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void WriteMessageClassDeclarations(
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const protobuf::Descriptor* descriptor,
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const std::vector<const protobuf::FieldDescriptor*>& file_exts,
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const std::vector<const protobuf::EnumDescriptor*>& file_enums,
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Output& output) {
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if (IsMapEntryMessage(descriptor)) {
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// Skip map entry generation. Low level accessors for maps are
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// generated that don't require a separate map type.
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return;
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}
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// Forward declaration of Proto Class for GCC handling of free friend method.
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output("class $0;\n", ClassName(descriptor));
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output("namespace internal {\n\n");
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WriteModelAccessDeclaration(descriptor, output);
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output("\n");
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WriteInternalForwardDeclarationsInHeader(descriptor, output);
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output("\n");
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output("} // namespace internal\n\n");
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WriteModelPublicDeclaration(descriptor, file_exts, file_enums, output);
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output("namespace internal {\n");
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WriteModelCProxyDeclaration(descriptor, output);
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WriteModelProxyDeclaration(descriptor, output);
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output("} // namespace internal\n\n");
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}
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void WriteModelAccessDeclaration(const protobuf::Descriptor* descriptor,
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Output& output) {
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output(
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R"cc(
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class $0Access {
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public:
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$0Access() {}
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$0Access($1* msg, upb_Arena* arena) : msg_(msg), arena_(arena) {
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assert(arena != nullptr);
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} // NOLINT
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$0Access(const $1* msg, upb_Arena* arena)
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: msg_(const_cast<$1*>(msg)), arena_(arena) {
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assert(arena != nullptr);
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} // NOLINT
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void* GetInternalArena() const { return arena_; }
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)cc",
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ClassName(descriptor), MessageName(descriptor));
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WriteFieldAccessorsInHeader(descriptor, output);
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WriteOneofAccessorsInHeader(descriptor, output);
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output.Indent();
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output(
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R"cc(
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private:
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friend class $2;
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friend class $0Proxy;
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friend class $0CProxy;
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friend struct ::hpb::internal::PrivateAccess;
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$1* msg_;
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upb_Arena* arena_;
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)cc",
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ClassName(descriptor), MessageName(descriptor),
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QualifiedClassName(descriptor));
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output.Outdent();
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output("};\n");
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}
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std::string UnderscoresToCamelCase(absl::string_view input,
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bool cap_next_letter) {
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std::string result;
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for (size_t i = 0; i < input.size(); i++) {
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if (absl::ascii_islower(input[i])) {
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if (cap_next_letter) {
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result += absl::ascii_toupper(input[i]);
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} else {
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result += input[i];
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}
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cap_next_letter = false;
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} else if (absl::ascii_isupper(input[i])) {
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// Capital letters are left as-is.
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result += input[i];
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cap_next_letter = false;
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} else if (absl::ascii_isdigit(input[i])) {
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result += input[i];
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cap_next_letter = true;
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} else {
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cap_next_letter = true;
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}
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}
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return result;
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}
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std::string FieldConstantName(const protobuf::FieldDescriptor* field) {
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std::string field_name = UnderscoresToCamelCase(field->name(), true);
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std::string result = absl::StrCat("k", field_name, "FieldNumber");
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if (!field->is_extension() &&
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field->containing_type()->FindFieldByCamelcaseName(
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field->camelcase_name()) != field) {
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// This field's camelcase name is not unique, add field number to make it
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// unique.
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absl::StrAppend(&result, "_", field->number());
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}
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return result;
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}
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void WriteConstFieldNumbers(Output& output,
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const protobuf::Descriptor* descriptor) {
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for (auto field : FieldRange(descriptor)) {
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output("static constexpr ::uint32_t $0 = $1;\n", FieldConstantName(field),
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field->number());
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}
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output("\n\n");
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}
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void WriteModelPublicDeclaration(
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const protobuf::Descriptor* descriptor,
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const std::vector<const protobuf::FieldDescriptor*>& file_exts,
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const std::vector<const protobuf::EnumDescriptor*>& file_enums,
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Output& output) {
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output(
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R"cc(
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class $0 final : private internal::$0Access {
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public:
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using Access = internal::$0Access;
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using Proxy = internal::$0Proxy;
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using CProxy = internal::$0CProxy;
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$0();
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$0(const $0& from);
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$0& operator=(const $3& from);
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$0(const CProxy& from);
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$0(const Proxy& from);
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$0& operator=(const CProxy& from);
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$0($0&& m)
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: Access(std::exchange(m.msg_, nullptr),
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std::exchange(m.arena_, nullptr)),
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owned_arena_(std::move(m.owned_arena_)) {}
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$0& operator=($0&& m) {
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msg_ = std::exchange(m.msg_, nullptr);
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arena_ = std::exchange(m.arena_, nullptr);
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owned_arena_ = std::move(m.owned_arena_);
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return *this;
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}
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)cc",
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ClassName(descriptor),
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::upb::generator::MessageInit(descriptor->full_name()),
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MessageName(descriptor), QualifiedClassName(descriptor));
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WriteUsingAccessorsInHeader(descriptor, MessageClassType::kMessage, output);
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WriteUsingEnumsInHeader(descriptor, file_enums, output);
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WriteDefaultInstanceHeader(descriptor, output);
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WriteExtensionIdentifiersInClassHeader(descriptor, file_exts, output);
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if (descriptor->extension_range_count()) {
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// for typetrait checking
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output("using ExtendableType = $0;\n", ClassName(descriptor));
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}
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// Note: free function friends that are templates such as ::hpb::Parse
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// require explicit <$2> type parameter in declaration to be able to compile
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// with gcc otherwise the compiler will fail with
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// "has not been declared within namespace" error. Even though there is a
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// namespace qualifier, cross namespace matching fails.
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output.Indent();
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output(
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R"cc(
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static const upb_MiniTable* minitable();
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using $0Access::GetInternalArena;
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)cc",
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ClassName(descriptor));
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output("\n");
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WriteConstFieldNumbers(output, descriptor);
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output(
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R"cc(
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private:
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const upb_Message* msg() const { return UPB_UPCAST(msg_); }
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upb_Message* msg() { return UPB_UPCAST(msg_); }
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$0(upb_Message* msg, upb_Arena* arena) : $0Access() {
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msg_ = ($1*)msg;
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arena_ = owned_arena_.ptr();
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upb_Arena_Fuse(arena_, arena);
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}
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::hpb::Arena owned_arena_;
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friend struct ::hpb::internal::PrivateAccess;
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friend Proxy;
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friend CProxy;
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friend absl::StatusOr<$2>(::hpb::Parse<$2>(absl::string_view bytes,
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int options));
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friend absl::StatusOr<$2>(::hpb::Parse<$2>(
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absl::string_view bytes,
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const ::hpb::ExtensionRegistry& extension_registry, int options));
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friend upb_Arena* ::hpb::internal::GetArena<$0>($0* message);
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friend upb_Arena* ::hpb::internal::GetArena<$0>(::hpb::Ptr<$0> message);
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friend $0(::hpb::internal::MoveMessage<$0>(upb_Message* msg, upb_Arena* arena));
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)cc",
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ClassName(descriptor), MessageName(descriptor),
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QualifiedClassName(descriptor));
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output.Outdent();
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output("};\n\n");
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}
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void WriteModelProxyDeclaration(const protobuf::Descriptor* descriptor,
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Output& output) {
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// Foo::Proxy.
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output(
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R"cc(
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class $0Proxy final : private internal::$0Access {
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public:
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$0Proxy() = delete;
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$0Proxy(const $0Proxy& m) : internal::$0Access() {
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msg_ = m.msg_;
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arena_ = m.arena_;
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}
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$0Proxy($0* m) : internal::$0Access() {
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msg_ = m->msg_;
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arena_ = m->arena_;
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}
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$0Proxy operator=(const $0Proxy& m) {
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msg_ = m.msg_;
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arena_ = m.arena_;
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return *this;
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}
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using $0Access::GetInternalArena;
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)cc",
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ClassName(descriptor));
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WriteUsingAccessorsInHeader(descriptor, MessageClassType::kMessageProxy,
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output);
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output("\n");
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output.Indent(1);
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output(
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R"cc(
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private:
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upb_Message* msg() const { return UPB_UPCAST(msg_); }
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$0Proxy(upb_Message* msg, upb_Arena* arena)
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: internal::$0Access(($1*)msg, arena) {}
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friend $0::Proxy(::hpb::CreateMessage<$0>(::hpb::Arena& arena));
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friend $0::Proxy(::hpb::internal::CreateMessageProxy<$0>(upb_Message*,
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upb_Arena*));
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friend struct ::hpb::internal::PrivateAccess;
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friend class RepeatedFieldProxy;
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friend class $0CProxy;
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friend class $0Access;
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friend class ::hpb::Ptr<$0>;
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friend class ::hpb::Ptr<const $0>;
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static const upb_MiniTable* minitable() { return $0::minitable(); }
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friend const upb_MiniTable* ::hpb::interop::upb::GetMiniTable<$0Proxy>(
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const $0Proxy* message);
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friend const upb_MiniTable* ::hpb::interop::upb::GetMiniTable<$0Proxy>(
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::hpb::Ptr<$0Proxy> message);
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friend upb_Arena* ::hpb::internal::GetArena<$2>($2* message);
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friend upb_Arena* ::hpb::internal::GetArena<$2>(::hpb::Ptr<$2> message);
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static void Rebind($0Proxy& lhs, const $0Proxy& rhs) {
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lhs.msg_ = rhs.msg_;
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lhs.arena_ = rhs.arena_;
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}
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)cc",
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ClassName(descriptor), MessageName(descriptor),
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QualifiedClassName(descriptor));
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output.Outdent(1);
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output("};\n\n");
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}
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void WriteModelCProxyDeclaration(const protobuf::Descriptor* descriptor,
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Output& output) {
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// Foo::CProxy.
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output(
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R"cc(
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class $0CProxy final : private internal::$0Access {
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public:
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$0CProxy() = delete;
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$0CProxy(const $0* m)
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: internal::$0Access(m->msg_, ::hpb::internal::GetArena(m)) {}
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$0CProxy($0Proxy m);
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using $0Access::GetInternalArena;
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)cc",
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ClassName(descriptor), MessageName(descriptor));
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WriteUsingAccessorsInHeader(descriptor, MessageClassType::kMessageCProxy,
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output);
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output.Indent(1);
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output(
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R"cc(
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private:
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using AsNonConst = $0Proxy;
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const upb_Message* msg() const { return UPB_UPCAST(msg_); }
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$0CProxy(const upb_Message* msg, upb_Arena* arena)
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: internal::$0Access(($1*)msg, arena){};
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friend struct ::hpb::internal::PrivateAccess;
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friend class RepeatedFieldProxy;
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friend class ::hpb::Ptr<$0>;
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friend class ::hpb::Ptr<const $0>;
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static const upb_MiniTable* minitable() { return $0::minitable(); }
|
|
|
|
friend const upb_MiniTable* ::hpb::interop::upb::GetMiniTable<$0CProxy>(
|
|
|
|
const $0CProxy* message);
|
|
|
|
friend const upb_MiniTable* ::hpb::interop::upb::GetMiniTable<$0CProxy>(
|
|
|
|
::hpb::Ptr<$0CProxy> message);
|
|
|
|
|
|
|
|
static void Rebind($0CProxy& lhs, const $0CProxy& rhs) {
|
|
|
|
lhs.msg_ = rhs.msg_;
|
|
|
|
lhs.arena_ = rhs.arena_;
|
|
|
|
}
|
|
|
|
)cc",
|
|
|
|
ClassName(descriptor), MessageName(descriptor));
|
|
|
|
output.Outdent(1);
|
|
|
|
output("};\n\n");
|
|
|
|
}
|
|
|
|
|
|
|
|
void WriteDefaultInstanceHeader(const protobuf::Descriptor* message,
|
|
|
|
Output& output) {
|
|
|
|
output(" static ::hpb::Ptr<const $0> default_instance();\n",
|
|
|
|
ClassName(message));
|
|
|
|
}
|
|
|
|
|
|
|
|
void WriteMessageImplementation(
|
|
|
|
const protobuf::Descriptor* descriptor,
|
|
|
|
const std::vector<const protobuf::FieldDescriptor*>& file_exts,
|
|
|
|
Output& output) {
|
|
|
|
bool message_is_map_entry = descriptor->options().map_entry();
|
|
|
|
if (!message_is_map_entry) {
|
|
|
|
// Constructor.
|
|
|
|
output(
|
|
|
|
R"cc(
|
|
|
|
$0::$0() : $0Access() {
|
|
|
|
arena_ = owned_arena_.ptr();
|
|
|
|
msg_ = $1_new(arena_);
|
|
|
|
}
|
|
|
|
$0::$0(const $0& from) : $0Access() {
|
|
|
|
arena_ = owned_arena_.ptr();
|
|
|
|
msg_ = ($1*)::hpb::internal::DeepClone(UPB_UPCAST(from.msg_), &$2, arena_);
|
|
|
|
}
|
|
|
|
$0::$0(const CProxy& from) : $0Access() {
|
|
|
|
arena_ = owned_arena_.ptr();
|
|
|
|
msg_ = ($1*)::hpb::internal::DeepClone(
|
|
|
|
::hpb::internal::GetInternalMsg(&from), &$2, arena_);
|
|
|
|
}
|
|
|
|
$0::$0(const Proxy& from) : $0(static_cast<const CProxy&>(from)) {}
|
|
|
|
internal::$0CProxy::$0CProxy($0Proxy m) : $0Access() {
|
|
|
|
arena_ = m.arena_;
|
|
|
|
msg_ = ($1*)::hpb::internal::GetInternalMsg(&m);
|
|
|
|
}
|
|
|
|
$0& $0::operator=(const $3& from) {
|
|
|
|
arena_ = owned_arena_.ptr();
|
|
|
|
msg_ = ($1*)::hpb::internal::DeepClone(UPB_UPCAST(from.msg_), &$2, arena_);
|
|
|
|
return *this;
|
|
|
|
}
|
|
|
|
$0& $0::operator=(const CProxy& from) {
|
|
|
|
arena_ = owned_arena_.ptr();
|
|
|
|
msg_ = ($1*)::hpb::internal::DeepClone(
|
|
|
|
::hpb::internal::GetInternalMsg(&from), &$2, arena_);
|
|
|
|
return *this;
|
|
|
|
}
|
|
|
|
)cc",
|
|
|
|
ClassName(descriptor), MessageName(descriptor),
|
|
|
|
::upb::generator::MessageInit(descriptor->full_name()),
|
|
|
|
QualifiedClassName(descriptor));
|
|
|
|
output("\n");
|
|
|
|
// Minitable
|
|
|
|
output(
|
|
|
|
R"cc(
|
|
|
|
const upb_MiniTable* $0::minitable() { return &$1; }
|
|
|
|
)cc",
|
|
|
|
ClassName(descriptor),
|
|
|
|
::upb::generator::MessageInit(descriptor->full_name()));
|
|
|
|
output("\n");
|
|
|
|
}
|
|
|
|
|
upb is self-hosting!
This CL changes the upb compiler to no longer depend on C++ protobuf libraries. upb now uses its own reflection libraries to implement its code generator.
# Key Benefits
1. upb can now use its own reflection libraries throughout the compiler. This makes upb more consistent and principled, and gives us more chances to dogfood our own C++ reflection API. This highlighted several parts of the C++ reflection API that were incomplete.
2. This CL removes code duplication that previously existed in the compiler. The upb reflection library has code to build MiniDescriptors and MiniTables out of descriptors, but prior to this CL the upb compiler could not use it. The upb compiler had a separate copy of this logic, and the compiler's copy of this logic was especially tricky and hard to maintain. This CL removes the separate copy of that logic.
3. This CL (mostly) removes upb's dependency on the C++ protobuf library. We still depend on `protoc` (the binary), but the runtime and compiler no longer link against C++'s libraries. This opens up the possibility of speeding up some builds significantly if we can use a prebuilt `protoc` binary.
# Bootstrap Stages
To bootstrap, we check in a copy of our generated code for `descriptor.proto` and `plugin.proto`. This allows the compiler to depend on the generated code for these two protos without creating a circular dependency. This code is checked in to the `stage0` directory.
The bootstrapping process is divided into a few stages. All `cc_library()`, `upb_proto_library()`, and `cc_binary()` targets that would otherwise be circular participate in this staging process. That currently includes:
* `//third_party/upb:descriptor_upb_proto`
* `//third_party/upb:plugin_upb_proto`
* `//third_party/upb:reflection`
* `//third_party/upb:reflection_internal`
* `//third_party/upbc:common`
* `//third_party/upbc:file_layout`
* `//third_party/upbc:plugin`
* `//third_party/upbc:protoc-gen-upb`
For each of these targets, we produce a rule for each stage (the logic for this is nicely encapsulated in Blaze/Bazel macros like `bootstrap_cc_library()` and `bootstrap_upb_proto_library()`, so the `BUILD` file remains readable). For example:
* `//third_party/upb:descriptor_upb_proto_stage0`
* `//third_party/upb:descriptor_upb_proto_stage1`
* `//third_party/upb:descriptor_upb_proto`
The stages are:
1. `stage0`: This uses the checked-in version of the generated code. The stage0 compiler is correct and outputs the same code as all other compilers, but it is unnecessarily slow because its protos were compiled in bootstrap mode. The stage0 compiler is used to generate protos for stage1.
2. `stage1`: The stage1 compiler is correct and fast, and therefore we use it in almost all cases (eg. `upb_proto_library()`). However its own protos were not generated using `upb_proto_library()`, so its `cc_library()` targets cannot be safely mixed with `upb_proto_library()`, as this would lead to duplicate symbols.
3. final (no stage): The final compiler is identical to the `stage1` compiler. The only difference is that its protos were built with `upb_proto_library()`. This doesn't matter very much for the compiler binary, but for the `cc_library()` targets like `//third_party/upb:reflection`, only the final targets can be safely linked in by other applications.
# "Bootstrap Mode" Protos
The checked-in generated code is generated in a special "bootstrap" mode that is a bit different than normal generated code. Bootstrap mode avoids depending on the internal representation of MiniTables or the messages, at the cost of slower runtime performance.
Bootstrap mode only interacts with MiniTables and messages using public APIs such as `upb_MiniTable_Build()`, `upb_Message_GetInt32()`, etc. This is very important as it allows us to change the internal representation without needing to regenerate our bootstrap protos. This will make it far easier to write CLs that change the internal representation, because it avoids the awkward dance of trying to regenerate the bootstrap protos when the compiler itself is broken due to bootstrap protos being out of date.
The bootstrap generated code does have two downsides:
1. The accessors are less efficient, because they look up MiniTable fields by number instead of hard-coding the MiniTableField into the generated code.
2. It requires runtime initialization of the MiniTables, which costs CPU cycles at startup, and also allocates memory which is never freed. Per google3 rules this is not really a leak, since this memory is still reachable via static variables, but it is undesirable in many contexts. We could fix this part by introducing the equivalent of `google::protobuf::ShutdownProtobufLibrary()`).
These downsides are fine for the bootstrapping process, but they are reason enough not to enable bootstrap mode in general for all protos.
# Bootstrapping Always Uses OSS Protos
To enable smooth syncing between Google3 and OSS, we always use an OSS version of the checked in generated code for `stage0`, even in google3.
This requires that the google3 code can be switched to reference the OSS proto names using a preprocessor define. We introduce the `UPB_DESC(xyz)` macro for this, which will expand into either `proto2_xyz` or `google_protobuf_xyz`. Any libraries used in `stage0` must use `UPB_DESC(xyz)` rather than refer to the symbol names directly.
PiperOrigin-RevId: 501458451
2 years ago
|
|
|
WriteAccessorsInSource(descriptor, output);
|
|
|
|
|
|
|
|
if (!message_is_map_entry) {
|
|
|
|
output(
|
|
|
|
R"cc(
|
|
|
|
struct $0DefaultTypeInternal {
|
|
|
|
$1* msg;
|
|
|
|
upb_Arena* arena;
|
|
|
|
};
|
|
|
|
static $0DefaultTypeInternal _$0DefaultTypeBuilder() {
|
|
|
|
upb_Arena* arena = upb_Arena_New();
|
|
|
|
return $0DefaultTypeInternal{$1_new(arena), arena};
|
|
|
|
}
|
|
|
|
$0DefaultTypeInternal _$0_default_instance_ = _$0DefaultTypeBuilder();
|
|
|
|
)cc",
|
|
|
|
ClassName(descriptor), MessageName(descriptor));
|
|
|
|
|
|
|
|
output(
|
|
|
|
R"cc(
|
|
|
|
::hpb::Ptr<const $0> $0::default_instance() {
|
|
|
|
return ::hpb::interop::upb::MakeCHandle<$0>(
|
|
|
|
(upb_Message *)_$0_default_instance_.msg,
|
|
|
|
_$0_default_instance_.arena);
|
|
|
|
}
|
|
|
|
)cc",
|
|
|
|
ClassName(descriptor));
|
|
|
|
|
|
|
|
WriteExtensionIdentifiersImplementation(descriptor, file_exts, output);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
void WriteInternalForwardDeclarationsInHeader(
|
|
|
|
const protobuf::Descriptor* message, Output& output) {
|
|
|
|
// Write declaration for internal re-usable default_instance without
|
|
|
|
// leaking implementation.
|
|
|
|
output(
|
|
|
|
R"cc(
|
|
|
|
struct $0DefaultTypeInternal;
|
|
|
|
extern $0DefaultTypeInternal _$0_default_instance_;
|
|
|
|
)cc",
|
|
|
|
ClassName(message));
|
|
|
|
}
|
|
|
|
|
|
|
|
void WriteExtensionIdentifiersInClassHeader(
|
|
|
|
const protobuf::Descriptor* message,
|
|
|
|
const std::vector<const protobuf::FieldDescriptor*>& file_exts,
|
|
|
|
Output& output) {
|
|
|
|
for (auto* ext : file_exts) {
|
|
|
|
if (ext->extension_scope() &&
|
|
|
|
ext->extension_scope()->full_name() == message->full_name()) {
|
|
|
|
WriteExtensionIdentifierHeader(ext, output);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
void WriteExtensionIdentifiersImplementation(
|
|
|
|
const protobuf::Descriptor* message,
|
|
|
|
const std::vector<const protobuf::FieldDescriptor*>& file_exts,
|
|
|
|
Output& output) {
|
|
|
|
for (auto* ext : file_exts) {
|
|
|
|
if (ext->extension_scope() &&
|
|
|
|
ext->extension_scope()->full_name() == message->full_name()) {
|
|
|
|
WriteExtensionIdentifier(ext, output);
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
void WriteUsingEnumsInHeader(
|
|
|
|
const protobuf::Descriptor* message,
|
|
|
|
const std::vector<const protobuf::EnumDescriptor*>& file_enums,
|
|
|
|
Output& output) {
|
|
|
|
for (auto* enum_descriptor : file_enums) {
|
|
|
|
std::string enum_type_name = EnumTypeName(enum_descriptor);
|
|
|
|
std::string enum_resolved_type_name =
|
|
|
|
enum_descriptor->file()->package().empty() &&
|
|
|
|
enum_descriptor->containing_type() == nullptr
|
|
|
|
? absl::StrCat(kNoPackageNamePrefix,
|
|
|
|
ToCIdent(enum_descriptor->name()))
|
|
|
|
: enum_type_name;
|
|
|
|
if (enum_descriptor->containing_type() == nullptr ||
|
|
|
|
enum_descriptor->containing_type()->full_name() !=
|
|
|
|
message->full_name()) {
|
|
|
|
continue;
|
|
|
|
}
|
|
|
|
output("using $0", enum_descriptor->name());
|
|
|
|
if (enum_descriptor->options().deprecated()) {
|
|
|
|
output(" ABSL_DEPRECATED(\"Proto enum $0\")", enum_descriptor->name());
|
|
|
|
}
|
|
|
|
output(" = $0;", enum_resolved_type_name);
|
|
|
|
output("\n");
|
|
|
|
int value_count = enum_descriptor->value_count();
|
|
|
|
for (int i = 0; i < value_count; i++) {
|
|
|
|
output("static constexpr $0 $1", enum_descriptor->name(),
|
|
|
|
enum_descriptor->value(i)->name());
|
|
|
|
if (enum_descriptor->options().deprecated() ||
|
|
|
|
enum_descriptor->value(i)->options().deprecated()) {
|
|
|
|
output(" ABSL_DEPRECATED(\"Proto enum value $0\") ",
|
|
|
|
enum_descriptor->value(i)->name());
|
|
|
|
}
|
|
|
|
output(" = $0;\n", EnumValueSymbolInNameSpace(enum_descriptor,
|
|
|
|
enum_descriptor->value(i)));
|
|
|
|
}
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
} // namespace protobuf
|
|
|
|
} // namespace google::hpb_generator
|