2024-05-11 17:43:38 +08:00

663 lines
25 KiB
C++

// 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.
#include "google/protobuf/compiler/objectivec/message.h"
#include <algorithm>
#include <cstddef>
#include <memory>
#include <string>
#include <vector>
#include "absl/log/absl_log.h"
#include "absl/strings/escaping.h"
#include "absl/strings/str_cat.h"
#include "google/protobuf/compiler/objectivec/extension.h"
#include "google/protobuf/compiler/objectivec/helpers.h"
#include "google/protobuf/compiler/objectivec/names.h"
#include "google/protobuf/compiler/objectivec/oneof.h"
#include "google/protobuf/compiler/objectivec/text_format_decode_data.h"
#include "google/protobuf/descriptor.h"
#include "google/protobuf/descriptor.pb.h"
#include "google/protobuf/io/printer.h"
namespace google {
namespace protobuf {
namespace compiler {
namespace objectivec {
namespace {
bool IsMapEntryMessage(const Descriptor* descriptor) {
return descriptor->options().map_entry();
}
struct FieldOrderingByNumber {
inline bool operator()(const FieldDescriptor* a,
const FieldDescriptor* b) const {
return a->number() < b->number();
}
};
int OrderGroupForFieldDescriptor(const FieldDescriptor* descriptor) {
// The first item in the object structure is our uint32[] for has bits.
// We then want to order things to make the instances as small as
// possible. So we follow the has bits with:
// 1. Anything always 4 bytes - float, *32, enums
// 2. Anything that is always a pointer (they will be 8 bytes on 64 bit
// builds and 4 bytes on 32bit builds.
// 3. Anything always 8 bytes - double, *64
//
// NOTE: Bools aren't listed, they were stored in the has bits.
//
// Why? Using 64bit builds as an example, this means worse case, we have
// enough bools that we overflow 1 byte from 4 byte alignment, so 3 bytes
// are wasted before the 4 byte values. Then if we have an odd number of
// those 4 byte values, the 8 byte values will be pushed down by 32bits to
// keep them aligned. But the structure will end 8 byte aligned, so no
// waste on the end. If you did the reverse order, you could waste 4 bytes
// before the first 8 byte value (after the has array), then a single
// bool on the end would need 7 bytes of padding to make the overall
// structure 8 byte aligned; so 11 bytes, wasted total.
// Anything repeated is a GPB*Array/NSArray, so pointer.
if (descriptor->is_repeated()) {
return 3;
}
switch (descriptor->type()) {
// All always 8 bytes.
case FieldDescriptor::TYPE_DOUBLE:
case FieldDescriptor::TYPE_INT64:
case FieldDescriptor::TYPE_SINT64:
case FieldDescriptor::TYPE_UINT64:
case FieldDescriptor::TYPE_SFIXED64:
case FieldDescriptor::TYPE_FIXED64:
return 4;
// Pointers (string and bytes are NSString and NSData); 8 or 4 bytes
// depending on the build architecture.
case FieldDescriptor::TYPE_GROUP:
case FieldDescriptor::TYPE_MESSAGE:
case FieldDescriptor::TYPE_STRING:
case FieldDescriptor::TYPE_BYTES:
return 3;
// All always 4 bytes (enums are int32s).
case FieldDescriptor::TYPE_FLOAT:
case FieldDescriptor::TYPE_INT32:
case FieldDescriptor::TYPE_SINT32:
case FieldDescriptor::TYPE_UINT32:
case FieldDescriptor::TYPE_SFIXED32:
case FieldDescriptor::TYPE_FIXED32:
case FieldDescriptor::TYPE_ENUM:
return 2;
// 0 bytes. Stored in the has bits.
case FieldDescriptor::TYPE_BOOL:
return 99; // End of the list (doesn't really matter).
}
// Some compilers report reaching end of function even though all cases of
// the enum are handed in the switch.
ABSL_LOG(FATAL) << "Can't get here.";
return 0;
}
struct FieldOrderingByStorageSize {
inline bool operator()(const FieldDescriptor* a,
const FieldDescriptor* b) const {
// Order by grouping.
const int order_group_a = OrderGroupForFieldDescriptor(a);
const int order_group_b = OrderGroupForFieldDescriptor(b);
if (order_group_a != order_group_b) {
return order_group_a < order_group_b;
}
// Within the group, order by field number (provides stable ordering).
return a->number() < b->number();
}
};
struct ExtensionRangeOrdering {
bool operator()(const Descriptor::ExtensionRange* a,
const Descriptor::ExtensionRange* b) const {
return a->start_number() < b->start_number();
}
};
// This is a reduced case of Descriptor::ExtensionRange with just start and end.
struct SimpleExtensionRange {
SimpleExtensionRange(int start, int end) : start(start), end(end){};
int start; // inclusive
int end; // exclusive
// Descriptors expose extension ranges in the order they were defined in the
// file, but this reorders and merges the ranges that are contiguous (i.e. -
// [(21,30),(10,20)] -> [(10,30)])
static std::vector<SimpleExtensionRange> Normalize(
const Descriptor* descriptor) {
std::vector<const Descriptor::ExtensionRange*> sorted_extensions;
sorted_extensions.reserve(descriptor->extension_range_count());
for (int i = 0; i < descriptor->extension_range_count(); ++i) {
sorted_extensions.push_back(descriptor->extension_range(i));
}
std::sort(sorted_extensions.begin(), sorted_extensions.end(),
ExtensionRangeOrdering());
std::vector<SimpleExtensionRange> result;
result.reserve(sorted_extensions.size());
for (const auto ext : sorted_extensions) {
if (!result.empty() && result.back().end == ext->start_number()) {
result.back().end = ext->end_number();
} else {
result.emplace_back(ext->start_number(), ext->end_number());
}
}
return result;
}
};
// Sort the fields of the given Descriptor by number into a new[]'d array
// and return it.
const FieldDescriptor** SortFieldsByNumber(const Descriptor* descriptor) {
const FieldDescriptor** fields =
new const FieldDescriptor*[descriptor->field_count()];
for (int i = 0; i < descriptor->field_count(); i++) {
fields[i] = descriptor->field(i);
}
std::sort(fields, fields + descriptor->field_count(),
FieldOrderingByNumber());
return fields;
}
// Sort the fields of the given Descriptor by storage size into a new[]'d
// array and return it.
const FieldDescriptor** SortFieldsByStorageSize(const Descriptor* descriptor) {
const FieldDescriptor** fields =
new const FieldDescriptor*[descriptor->field_count()];
for (int i = 0; i < descriptor->field_count(); i++) {
fields[i] = descriptor->field(i);
}
std::sort(fields, fields + descriptor->field_count(),
FieldOrderingByStorageSize());
return fields;
}
} // namespace
MessageGenerator::MessageGenerator(const std::string& file_description_name,
const Descriptor* descriptor)
: file_description_name_(file_description_name),
descriptor_(descriptor),
field_generators_(descriptor),
class_name_(ClassName(descriptor_)),
deprecated_attribute_(GetOptionalDeprecatedAttribute(
descriptor, descriptor->file(), false, true)) {
for (int i = 0; i < descriptor_->real_oneof_decl_count(); i++) {
oneof_generators_.push_back(
std::make_unique<OneofGenerator>(descriptor_->oneof_decl(i)));
}
// Assign has bits:
// 1. FieldGeneratorMap::CalculateHasBits() loops through the fields seeing
// who needs has bits and assigning them.
// 2. FieldGenerator::SetOneofIndexBase() overrides has_bit with a negative
// index that groups all the elements in the oneof.
size_t num_has_bits = field_generators_.CalculateHasBits();
size_t sizeof_has_storage = (num_has_bits + 31) / 32;
if (sizeof_has_storage == 0) {
// In the case where no field needs has bits, don't let the _has_storage_
// end up as zero length (zero length arrays are sort of a grey area
// since it has to be at the start of the struct). This also ensures a
// field with only oneofs keeps the required negative indices they need.
sizeof_has_storage = 1;
}
// Tell all the fields the oneof base.
for (const auto& generator : oneof_generators_) {
generator->SetOneofIndexBase(sizeof_has_storage);
}
field_generators_.SetOneofIndexBase(sizeof_has_storage);
// sizeof_has_storage needs enough bits for the single fields that aren't in
// any oneof, and then one int32 for each oneof (to store the field number).
sizeof_has_storage += oneof_generators_.size();
sizeof_has_storage_ = sizeof_has_storage;
}
void MessageGenerator::AddExtensionGenerators(
std::vector<std::unique_ptr<ExtensionGenerator>>* extension_generators) {
for (int i = 0; i < descriptor_->extension_count(); i++) {
extension_generators->push_back(std::make_unique<ExtensionGenerator>(
class_name_, descriptor_->extension(i)));
extension_generators_.push_back(extension_generators->back().get());
}
}
void MessageGenerator::DetermineForwardDeclarations(
absl::btree_set<std::string>* fwd_decls,
bool include_external_types) const {
if (IsMapEntryMessage(descriptor_)) {
return;
}
for (int i = 0; i < descriptor_->field_count(); i++) {
const FieldDescriptor* fieldDescriptor = descriptor_->field(i);
field_generators_.get(fieldDescriptor)
.DetermineForwardDeclarations(fwd_decls, include_external_types);
}
}
void MessageGenerator::DetermineObjectiveCClassDefinitions(
absl::btree_set<std::string>* fwd_decls) const {
if (!IsMapEntryMessage(descriptor_)) {
// Forward declare this class, as a linker symbol, so the symbol can be used
// to reference the class instead of calling +class later.
fwd_decls->insert(ObjCClassDeclaration(class_name_));
for (int i = 0; i < descriptor_->field_count(); i++) {
const FieldDescriptor* fieldDescriptor = descriptor_->field(i);
field_generators_.get(fieldDescriptor)
.DetermineObjectiveCClassDefinitions(fwd_decls);
}
}
const Descriptor* containing_descriptor = descriptor_->containing_type();
if (containing_descriptor != nullptr) {
std::string containing_class = ClassName(containing_descriptor);
fwd_decls->insert(ObjCClassDeclaration(containing_class));
}
}
void MessageGenerator::GenerateMessageHeader(io::Printer* printer) const {
// This a a map entry message, do nothing.
if (IsMapEntryMessage(descriptor_)) {
return;
}
auto vars = printer->WithVars({{"classname", class_name_}});
printer->Emit(
{{"deprecated_attribute", deprecated_attribute_},
{"message_comments",
[&] {
EmitCommentsString(printer, descriptor_,
CommentStringFlags::kForceMultiline);
}},
{"message_fieldnum_enum",
[&] {
if (descriptor_->field_count() == 0) return;
printer->Emit(R"objc(
typedef GPB_ENUM($classname$_FieldNumber) {
$message_fieldnum_enum_values$,
};
)objc");
printer->Emit("\n");
}},
{"message_fieldnum_enum_values",
[&] {
std::unique_ptr<const FieldDescriptor*[]> sorted_fields(
SortFieldsByNumber(descriptor_));
for (size_t i = 0; i < (size_t)descriptor_->field_count(); i++) {
field_generators_.get(sorted_fields[i])
.GenerateFieldNumberConstant(printer);
}
}},
{"oneof_enums",
[&] {
for (const auto& generator : oneof_generators_) {
generator->GenerateCaseEnum(printer);
}
}},
{"message_properties",
[&] {
std::vector<char> seen_oneofs(oneof_generators_.size(), 0);
for (int i = 0; i < descriptor_->field_count(); i++) {
const FieldDescriptor* field = descriptor_->field(i);
const OneofDescriptor* oneof = field->real_containing_oneof();
if (oneof) {
const size_t oneof_index = (size_t)oneof->index();
if (!seen_oneofs[oneof_index]) {
seen_oneofs[oneof_index] = 1;
oneof_generators_[oneof_index]
->GeneratePublicCasePropertyDeclaration(printer);
}
}
field_generators_.get(field).GeneratePropertyDeclaration(printer);
}
}}},
R"objc(
#pragma mark - $classname$
$message_fieldnum_enum$
$oneof_enums$
$message_comments$
$deprecated_attribute$GPB_FINAL @interface $classname$ : GPBMessage
$message_properties$
@end
)objc");
printer->Emit("\n");
for (int i = 0; i < descriptor_->field_count(); i++) {
field_generators_.get(descriptor_->field(i))
.GenerateCFunctionDeclarations(printer);
}
if (!oneof_generators_.empty()) {
for (const auto& generator : oneof_generators_) {
generator->GenerateClearFunctionDeclaration(printer);
}
printer->Emit("\n");
}
if (descriptor_->extension_count() > 0) {
printer->Emit({{"extension_info",
[&] {
for (const auto* generator : extension_generators_) {
generator->GenerateMembersHeader(printer);
}
}}},
R"objc(
@interface $classname$ (DynamicMethods)
$extension_info$
@end
)objc");
printer->Emit("\n");
}
}
void MessageGenerator::GenerateSource(io::Printer* printer) const {
if (IsMapEntryMessage(descriptor_)) {
return;
}
std::unique_ptr<const FieldDescriptor*[]> sorted_fields(
SortFieldsByNumber(descriptor_));
std::unique_ptr<const FieldDescriptor*[]> size_order_fields(
SortFieldsByStorageSize(descriptor_));
std::vector<SimpleExtensionRange> sorted_extensions(
SimpleExtensionRange::Normalize(descriptor_));
bool has_fields = descriptor_->field_count() > 0;
bool need_defaults = field_generators_.DoesAnyFieldHaveNonZeroDefault();
TextFormatDecodeData text_format_decode_data;
for (int i = 0; i < descriptor_->field_count(); ++i) {
const FieldGenerator& field_generator =
field_generators_.get(sorted_fields[i]);
if (field_generator.needs_textformat_name_support()) {
text_format_decode_data.AddString(sorted_fields[i]->number(),
field_generator.generated_objc_name(),
field_generator.raw_field_name());
}
}
const absl::string_view field_description_type(
need_defaults ? "GPBMessageFieldDescriptionWithDefault"
: "GPBMessageFieldDescription");
std::vector<std::string> init_flags;
init_flags.push_back("GPBDescriptorInitializationFlag_UsesClassRefs");
init_flags.push_back("GPBDescriptorInitializationFlag_Proto3OptionalKnown");
init_flags.push_back(
"GPBDescriptorInitializationFlag_ClosedEnumSupportKnown");
if (need_defaults) {
init_flags.push_back("GPBDescriptorInitializationFlag_FieldsWithDefault");
}
if (descriptor_->options().message_set_wire_format()) {
init_flags.push_back("GPBDescriptorInitializationFlag_WireFormat");
}
printer->Emit(
{{"classname", class_name_},
{"clang_diagnostic_push",
[&] {
if (deprecated_attribute_.empty()) return;
// No warnings when compiling the impl of this deprecated class.
printer->Emit(R"objc(
#pragma clang diagnostic push
#pragma clang diagnostic ignored "-Wdeprecated-implementations"
)objc");
printer->Emit("\n");
}},
{"clang_diagnostic_pop",
[&] {
if (deprecated_attribute_.empty()) return;
printer->Emit(R"objc(
#pragma clang diagnostic pop
)objc");
printer->Emit("\n");
}},
{"property_implementation",
[&] {
for (const auto& generator : oneof_generators_) {
generator->GeneratePropertyImplementation(printer);
}
for (int i = 0; i < descriptor_->field_count(); i++) {
field_generators_.get(descriptor_->field(i))
.GeneratePropertyImplementation(printer);
}
}},
{"sizeof_has_storage", sizeof_has_storage_},
{"storage_fields",
[&] {
for (int i = 0; i < descriptor_->field_count(); i++) {
field_generators_.get(size_order_fields[i])
.GenerateFieldStorageDeclaration(printer);
}
}},
{"descriptor_startup",
[&] {
// If the message scopes extensions, trigger the root class
// +initialize/+extensionRegistry as that is where the
// runtime support for extensions lives.
if (descriptor_->extension_count() > 0) {
printer->Emit(R"objc(
// Start up the root class to support the scoped extensions.
__unused Class rootStartup = [$root_class_name$ class];
)objc");
} else {
// The Root class has a debug runtime check, so if not
// starting that up, add the check.
printer->Emit("GPB_DEBUG_CHECK_RUNTIME_VERSIONS();\n");
}
}},
{"field_description_type", field_description_type},
{"declare_fields_static",
[&] {
if (!has_fields) return;
printer->Emit(R"objc(
static $field_description_type$ fields[] = {
$declare_fields_static_fields$,
};
)objc");
}},
{"declare_fields_static_fields",
[&] {
for (int i = 0; i < descriptor_->field_count(); ++i) {
const FieldGenerator& field_generator =
field_generators_.get(sorted_fields[i]);
field_generator.GenerateFieldDescription(printer, need_defaults);
}
}},
{"message_name", descriptor_->name()},
{"class_reference", ObjCClass(class_name_)},
{"file_description_name", file_description_name_},
{"fields", has_fields ? "fields" : "NULL"},
{"fields_count",
has_fields ? absl::StrCat("(uint32_t)(sizeof(fields) / sizeof(",
field_description_type, "))")
: "0"},
{"init_flags",
BuildFlagsString(FLAGTYPE_DESCRIPTOR_INITIALIZATION, init_flags)},
{"oneof_support",
[&] {
if (oneof_generators_.empty()) return;
printer->Emit(
{{"first_has_index", oneof_generators_[0]->HasIndexAsString()}},
R"objc(
static const char *oneofs[] = {
$declare_oneof_static_oneofs$,
};
[localDescriptor setupOneofs:oneofs
count:(uint32_t)(sizeof(oneofs) / sizeof(char*))
firstHasIndex:$first_has_index$];
)objc");
}},
{"declare_oneof_static_oneofs",
[&] {
for (const auto& generator : oneof_generators_) {
printer->Emit({{"name", generator->DescriptorName()}}, R"objc(
"$name$",
)objc");
}
}},
{"text_format_decode_support",
[&] {
if (text_format_decode_data.num_entries() == 0) return;
printer->Emit(R"objc(
#if !GPBOBJC_SKIP_MESSAGE_TEXTFORMAT_EXTRAS
static const char *extraTextFormatInfo =
$text_format_decode_support_blob$
[localDescriptor setupExtraTextInfo:extraTextFormatInfo];
#endif // !GPBOBJC_SKIP_MESSAGE_TEXTFORMAT_EXTRAS
)objc");
}},
{"text_format_decode_support_blob",
[&] {
static const int kBytesPerLine = 40; // allow for escaping
const std::string text_format_data_str(
text_format_decode_data.Data());
for (size_t i = 0; i < text_format_data_str.size();
i += kBytesPerLine) {
printer->Emit(
{{"data", EscapeTrigraphs(absl::CEscape(
text_format_data_str.substr(i, kBytesPerLine)))},
{"ending_semi",
(i + kBytesPerLine) < text_format_data_str.size() ? ""
: ";"}},
R"objc(
"$data$"$ending_semi$
)objc");
}
}},
{"extension_range_support",
[&] {
if (sorted_extensions.empty()) return;
printer->Emit(
{{"ranges",
[&] {
for (const auto& extension_range : sorted_extensions) {
printer->Emit({{"start", extension_range.start},
{"end", extension_range.end}},
"{ .start = $start$, .end = $end$ },\n");
}
}}},
R"objc(
static const GPBExtensionRange ranges[] = {
$ranges$,
};
[localDescriptor setupExtensionRanges:ranges
count:(uint32_t)(sizeof(ranges) / sizeof(GPBExtensionRange))];
)objc");
}},
{"containing_type_support",
[&] {
if (descriptor_->containing_type() == nullptr) return;
std::string containing_class =
ClassName(descriptor_->containing_type());
std::string parent_class_ref = ObjCClass(containing_class);
printer->Emit({{"parent_class_ref", parent_class_ref}}, R"objc(
[localDescriptor setupContainingMessageClass:$parent_class_ref$];
)objc");
}}},
R"objc(
#pragma mark - $classname$
$clang_diagnostic_push$;
@implementation $classname$
$property_implementation$
typedef struct $classname$__storage_ {
uint32_t _has_storage_[$sizeof_has_storage$];
$storage_fields$,
} $classname$__storage_;
// This method is threadsafe because it is initially called
// in +initialize for each subclass.
+ (GPBDescriptor *)descriptor {
static GPBDescriptor *descriptor = nil;
if (!descriptor) {
$descriptor_startup$;
$declare_fields_static$;
GPBDescriptor *localDescriptor =
[GPBDescriptor allocDescriptorForClass:$class_reference$
messageName:@"$message_name$"
fileDescription:&$file_description_name$
fields:$fields$
fieldCount:$fields_count$
storageSize:sizeof($classname$__storage_)
flags:$init_flags$];
$oneof_support$;
$text_format_decode_support$;
$extension_range_support$;
$containing_type_support$;
#if defined(DEBUG) && DEBUG
NSAssert(descriptor == nil, @"Startup recursed!");
#endif // DEBUG
descriptor = localDescriptor;
}
return descriptor;
}
@end
$clang_diagnostic_pop$;
)objc");
for (int i = 0; i < descriptor_->field_count(); i++) {
field_generators_.get(descriptor_->field(i))
.GenerateCFunctionImplementations(printer);
}
for (const auto& generator : oneof_generators_) {
generator->GenerateClearFunctionImplementation(printer);
}
}
} // namespace objectivec
} // namespace compiler
} // namespace protobuf
} // namespace google