tools/aapt2/compile/IdAssigner.cpp - android_frameworks_base - Gitiles

 /*
  * Copyright (C) 2015 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #include "compile/IdAssigner.h"

 #include <map>
 #include <unordered_map>

 #include "android-base/expected.h"
 #include "android-base/logging.h"

 #include "ResourceTable.h"
 #include "process/IResourceTableConsumer.h"
 #include "util/Util.h"

 using android::base::expected;
 using android::base::unexpected;

 namespace aapt {

 namespace {
 template <typename T>
 using Result = expected<T, std::string>;

 template <typename Id, typename Key>
 struct NextIdFinder {
   explicit NextIdFinder(Id start_id = 0u) : next_id_(start_id){};

   // Attempts to reserve an identifier for the specified key.
   // If the identifier is already reserved by a different key, an error message is returned.
   // Reserving identifiers must be completed before `NextId` is called for the first time.
   Result<Id> ReserveId(Key key, Id id);

   // Retrieves the next available identifier that has not been reserved.
   std::optional<Id> NextId();

  private:
   // Attempts to set `next_id_` to the next available identifier that has not been reserved.
   // Returns whether there were any available identifiers.
   std::optional<Id> SkipToNextAvailableId();

   Id next_id_;
   bool next_id_called_ = false;
   bool exhausted_ = false;
   std::map<Id, Key> pre_assigned_ids_;
   typename std::map<Id, Key>::iterator next_preassigned_id_;
 };

 struct TypeGroup {
   explicit TypeGroup(uint8_t package_id, uint8_t type_id)
       : package_id_(package_id), type_id_(type_id){};

   // Attempts to reserve the resource id for the specified resource name.
   // If the id is already reserved by a different name, an error message is returned.
   // Reserving identifiers must be completed before `NextId` is called for the first time.
   Result<std::monostate> ReserveId(const ResourceName& name, ResourceId id);

   // Retrieves the next available resource id that has not been reserved.
   Result<ResourceId> NextId();

  private:
   uint8_t package_id_;
   uint8_t type_id_;
   NextIdFinder<uint16_t, ResourceName> next_entry_id_;
 };

 struct IdAssignerContext {
   IdAssignerContext(std::string package_name, uint8_t package_id)
       : package_name_(std::move(package_name)), package_id_(package_id) {
   }

   // Attempts to reserve the resource id for the specified resource name.
   // Returns whether the id was reserved successfully.
   // Reserving identifiers must be completed before `NextId` is called for the first time.
   bool ReserveId(const ResourceName& name, ResourceId id, IDiagnostics* diag);

   // Retrieves the next available resource id that has not been reserved.
   std::optional<ResourceId> NextId(const ResourceName& name, IDiagnostics* diag);

  private:
   std::string package_name_;
   uint8_t package_id_;
   std::map<ResourceType, TypeGroup> types_;
   NextIdFinder<uint8_t, ResourceType> type_id_finder_ = NextIdFinder<uint8_t, ResourceType>(1);
 };

 }  // namespace

 bool IdAssigner::Consume(IAaptContext* context, ResourceTable* table) {
   IdAssignerContext assigned_ids(context->GetCompilationPackage(), context->GetPackageId());
   for (auto& package : table->packages) {
     for (auto& type : package->types) {
       for (auto& entry : type->entries) {
         const ResourceName name(package->name, type->type, entry->name);
         if (entry->id) {
           if (!assigned_ids.ReserveId(name, entry->id.value(), context->GetDiagnostics())) {
             return false;
           }
         }

         if (assigned_id_map_) {
           // Assign the pre-assigned stable ID meant for this resource.
           const auto iter = assigned_id_map_->find(name);
           if (iter != assigned_id_map_->end()) {
             const ResourceId assigned_id = iter->second;
             if (!assigned_ids.ReserveId(name, assigned_id, context->GetDiagnostics())) {
               return false;
             }
             entry->id = assigned_id;
           }
         }
       }
     }
   }

   if (assigned_id_map_) {
     // Reserve all the IDs mentioned in the stable ID map. That way we won't assig IDs that were
     // listed in the map if they don't exist in the table.
     for (const auto& stable_id_entry : *assigned_id_map_) {
       const ResourceName& pre_assigned_name = stable_id_entry.first;
       const ResourceId& pre_assigned_id = stable_id_entry.second;
       if (!assigned_ids.ReserveId(pre_assigned_name, pre_assigned_id, context->GetDiagnostics())) {
         return false;
       }
     }
   }

   // Assign any resources without IDs the next available ID. Gaps will be filled if possible,
   // unless those IDs have been reserved.
   for (auto& package : table->packages) {
     for (auto& type : package->types) {
       for (auto& entry : type->entries) {
         const ResourceName name(package->name, type->type, entry->name);
         if (entry->id) {
           continue;
         }
         auto id = assigned_ids.NextId(name, context->GetDiagnostics());
         if (!id.has_value()) {
           return false;
         }
         entry->id = id.value();
       }
     }
   }
   return true;
 }

 namespace {
 template <typename Id, typename Key>
 Result<Id> NextIdFinder<Id, Key>::ReserveId(Key key, Id id) {
   CHECK(!next_id_called_) << "ReserveId cannot be called after NextId";
   auto assign_result = pre_assigned_ids_.emplace(id, key);
   if (!assign_result.second && assign_result.first->second != key) {
     std::stringstream error;
     error << "ID " << id << " is already assigned to " << assign_result.first->second;
     return unexpected(error.str());
   }
   return id;
 }

 template <typename Id, typename Key>
 std::optional<Id> NextIdFinder<Id, Key>::NextId() {
   if (!next_id_called_) {
     next_id_called_ = true;
     next_preassigned_id_ = pre_assigned_ids_.begin();
   }
   return SkipToNextAvailableId();
 }

 template <typename Id, typename Key>
 std::optional<Id> NextIdFinder<Id, Key>::SkipToNextAvailableId() {
   if (exhausted_) {
     return {};
   }
   while (next_preassigned_id_ != pre_assigned_ids_.end()) {
     if (next_preassigned_id_->first == next_id_) {
       if (next_id_ == std::numeric_limits<Id>::max()) {
         // The last identifier was reserved so there are no more available identifiers.
         exhausted_ = true;
         return {};
       }
       ++next_id_;
       ++next_preassigned_id_;
       continue;
     }
     CHECK(next_preassigned_id_->first > next_id_) << "Preassigned IDs are not in sorted order";
     break;
   }
   if (next_id_ == std::numeric_limits<Id>::max()) {
     // There are no more identifiers after this one, but this one is still available so return it.
     exhausted_ = true;
   }
   return next_id_++;
 }

 Result<std::monostate> TypeGroup::ReserveId(const ResourceName& name, ResourceId id) {
   if (type_id_ != id.type_id()) {
     // Currently there cannot be multiple type ids for a single type.
     std::stringstream error;
     error << "type '" << name.type << "' already has ID " << id.type_id();
     return unexpected(error.str());
   }

   auto assign_result = next_entry_id_.ReserveId(name, id.entry_id());
   if (!assign_result.has_value()) {
     std::stringstream error;
     error << "entry " << assign_result.error();
     return unexpected(error.str());
   }
   return {};
 }

 Result<ResourceId> TypeGroup::NextId() {
   auto entry_id = next_entry_id_.NextId();
   if (!entry_id.has_value()) {
     std::stringstream error;
     error << "resource type ID has exceeded the maximum number of resource entries ("
           << (std::numeric_limits<uint16_t>::max() + 1u) << ")";
     return unexpected(error.str());
   }
   return ResourceId(package_id_, type_id_, entry_id.value());
 }

 bool IdAssignerContext::ReserveId(const ResourceName& name, ResourceId id, IDiagnostics* diag) {
   if (package_id_ != id.package_id()) {
     diag->Error(DiagMessage() << "can't assign ID " << id << " to resource " << name
                               << " because package already has ID " << id.package_id());
     return false;
   }

   auto type = types_.find(name.type);
   if (type == types_.end()) {
     // The type has not been assigned an id yet. Ensure that the specified id is not being used by
     // another type.
     auto assign_result = type_id_finder_.ReserveId(name.type, id.type_id());
     if (!assign_result.has_value()) {
       diag->Error(DiagMessage() << "can't assign ID " << id << " to resource " << name
                                 << " because type " << assign_result.error());
       return false;
     }
     type = types_.emplace(name.type, TypeGroup(package_id_, id.type_id())).first;
   }

   auto assign_result = type->second.ReserveId(name, id);
   if (!assign_result.has_value()) {
     diag->Error(DiagMessage() << "can't assign ID " << id << " to resource " << name << " because "
                               << assign_result.error());
     return false;
   }

   return true;
 }

 std::optional<ResourceId> IdAssignerContext::NextId(const ResourceName& name, IDiagnostics* diag) {
   // The package name is not known during the compile stage.
   // Resources without a package name are considered a part of the app being linked.
   CHECK(name.package.empty() || name.package == package_name_);
   auto type = types_.find(name.type);
   if (type == types_.end()) {
     auto next_type_id = type_id_finder_.NextId();
     CHECK(next_type_id.has_value()) << "resource type IDs allocated have exceeded maximum (256)";
     type = types_.emplace(name.type, TypeGroup(package_id_, next_type_id.value())).first;
   }

   auto assign_result = type->second.NextId();
   if (!assign_result.has_value()) {
     diag->Error(DiagMessage() << "can't assign resource ID to resource " << name << " because "
                               << assign_result.error());
     return {};
   }
   return assign_result.value();
 }
 }  // namespace

 }  // namespace aapt
	/*
	* Copyright (C) 2015 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#include "compile/IdAssigner.h"

	#include <map>
	#include <unordered_map>

	#include "android-base/expected.h"
	#include "android-base/logging.h"

	#include "ResourceTable.h"
	#include "process/IResourceTableConsumer.h"
	#include "util/Util.h"

	using android::base::expected;
	using android::base::unexpected;

	namespace aapt {

	namespace {
	template <typename T>
	using Result = expected<T, std::string>;

	template <typename Id, typename Key>
	struct NextIdFinder {
	explicit NextIdFinder(Id start_id = 0u) : next_id_(start_id){};

	// Attempts to reserve an identifier for the specified key.
	// If the identifier is already reserved by a different key, an error message is returned.
	// Reserving identifiers must be completed before `NextId` is called for the first time.
	Result<Id> ReserveId(Key key, Id id);

	// Retrieves the next available identifier that has not been reserved.
	std::optional<Id> NextId();

	private:
	// Attempts to set `next_id_` to the next available identifier that has not been reserved.
	// Returns whether there were any available identifiers.
	std::optional<Id> SkipToNextAvailableId();

	Id next_id_;
	bool next_id_called_ = false;
	bool exhausted_ = false;
	std::map<Id, Key> pre_assigned_ids_;
	typename std::map<Id, Key>::iterator next_preassigned_id_;
	};

	struct TypeGroup {
	explicit TypeGroup(uint8_t package_id, uint8_t type_id)
	: package_id_(package_id), type_id_(type_id){};

	// Attempts to reserve the resource id for the specified resource name.
	// If the id is already reserved by a different name, an error message is returned.
	// Reserving identifiers must be completed before `NextId` is called for the first time.
	Result<std::monostate> ReserveId(const ResourceName& name, ResourceId id);

	// Retrieves the next available resource id that has not been reserved.
	Result<ResourceId> NextId();

	private:
	uint8_t package_id_;
	uint8_t type_id_;
	NextIdFinder<uint16_t, ResourceName> next_entry_id_;
	};

	struct IdAssignerContext {
	IdAssignerContext(std::string package_name, uint8_t package_id)
	: package_name_(std::move(package_name)), package_id_(package_id) {
	}

	// Attempts to reserve the resource id for the specified resource name.
	// Returns whether the id was reserved successfully.
	// Reserving identifiers must be completed before `NextId` is called for the first time.
	bool ReserveId(const ResourceName& name, ResourceId id, IDiagnostics* diag);

	// Retrieves the next available resource id that has not been reserved.
	std::optional<ResourceId> NextId(const ResourceName& name, IDiagnostics* diag);

	private:
	std::string package_name_;
	uint8_t package_id_;
	std::map<ResourceType, TypeGroup> types_;
	NextIdFinder<uint8_t, ResourceType> type_id_finder_ = NextIdFinder<uint8_t, ResourceType>(1);
	};

	} // namespace

	bool IdAssigner::Consume(IAaptContext* context, ResourceTable* table) {
	IdAssignerContext assigned_ids(context->GetCompilationPackage(), context->GetPackageId());
	for (auto& package : table->packages) {
	for (auto& type : package->types) {
	for (auto& entry : type->entries) {
	const ResourceName name(package->name, type->type, entry->name);
	if (entry->id) {
	if (!assigned_ids.ReserveId(name, entry->id.value(), context->GetDiagnostics())) {
	return false;
	}
	}

	if (assigned_id_map_) {
	// Assign the pre-assigned stable ID meant for this resource.
	const auto iter = assigned_id_map_->find(name);
	if (iter != assigned_id_map_->end()) {
	const ResourceId assigned_id = iter->second;
	if (!assigned_ids.ReserveId(name, assigned_id, context->GetDiagnostics())) {
	return false;
	}
	entry->id = assigned_id;
	}
	}
	}
	}
	}

	if (assigned_id_map_) {
	// Reserve all the IDs mentioned in the stable ID map. That way we won't assig IDs that were
	// listed in the map if they don't exist in the table.
	for (const auto& stable_id_entry : *assigned_id_map_) {
	const ResourceName& pre_assigned_name = stable_id_entry.first;
	const ResourceId& pre_assigned_id = stable_id_entry.second;
	if (!assigned_ids.ReserveId(pre_assigned_name, pre_assigned_id, context->GetDiagnostics())) {
	return false;
	}
	}
	}

	// Assign any resources without IDs the next available ID. Gaps will be filled if possible,
	// unless those IDs have been reserved.
	for (auto& package : table->packages) {
	for (auto& type : package->types) {
	for (auto& entry : type->entries) {
	const ResourceName name(package->name, type->type, entry->name);
	if (entry->id) {
	continue;
	}
	auto id = assigned_ids.NextId(name, context->GetDiagnostics());
	if (!id.has_value()) {
	return false;
	}
	entry->id = id.value();
	}
	}
	}
	return true;
	}

	namespace {
	template <typename Id, typename Key>
	Result<Id> NextIdFinder<Id, Key>::ReserveId(Key key, Id id) {
	CHECK(!next_id_called_) << "ReserveId cannot be called after NextId";
	auto assign_result = pre_assigned_ids_.emplace(id, key);
	if (!assign_result.second && assign_result.first->second != key) {
	std::stringstream error;
	error << "ID " << id << " is already assigned to " << assign_result.first->second;
	return unexpected(error.str());
	}
	return id;
	}

	template <typename Id, typename Key>
	std::optional<Id> NextIdFinder<Id, Key>::NextId() {
	if (!next_id_called_) {
	next_id_called_ = true;
	next_preassigned_id_ = pre_assigned_ids_.begin();
	}
	return SkipToNextAvailableId();
	}

	template <typename Id, typename Key>
	std::optional<Id> NextIdFinder<Id, Key>::SkipToNextAvailableId() {
	if (exhausted_) {
	return {};
	}
	while (next_preassigned_id_ != pre_assigned_ids_.end()) {
	if (next_preassigned_id_->first == next_id_) {
	if (next_id_ == std::numeric_limits<Id>::max()) {
	// The last identifier was reserved so there are no more available identifiers.
	exhausted_ = true;
	return {};
	}
	++next_id_;
	++next_preassigned_id_;
	continue;
	}
	CHECK(next_preassigned_id_->first > next_id_) << "Preassigned IDs are not in sorted order";
	break;
	}
	if (next_id_ == std::numeric_limits<Id>::max()) {
	// There are no more identifiers after this one, but this one is still available so return it.
	exhausted_ = true;
	}
	return next_id_++;
	}

	Result<std::monostate> TypeGroup::ReserveId(const ResourceName& name, ResourceId id) {
	if (type_id_ != id.type_id()) {
	// Currently there cannot be multiple type ids for a single type.
	std::stringstream error;
	error << "type '" << name.type << "' already has ID " << id.type_id();
	return unexpected(error.str());
	}

	auto assign_result = next_entry_id_.ReserveId(name, id.entry_id());
	if (!assign_result.has_value()) {
	std::stringstream error;
	error << "entry " << assign_result.error();
	return unexpected(error.str());
	}
	return {};
	}

	Result<ResourceId> TypeGroup::NextId() {
	auto entry_id = next_entry_id_.NextId();
	if (!entry_id.has_value()) {
	std::stringstream error;
	error << "resource type ID has exceeded the maximum number of resource entries ("
	<< (std::numeric_limits<uint16_t>::max() + 1u) << ")";
	return unexpected(error.str());
	}
	return ResourceId(package_id_, type_id_, entry_id.value());
	}

	bool IdAssignerContext::ReserveId(const ResourceName& name, ResourceId id, IDiagnostics* diag) {
	if (package_id_ != id.package_id()) {
	diag->Error(DiagMessage() << "can't assign ID " << id << " to resource " << name
	<< " because package already has ID " << id.package_id());
	return false;
	}

	auto type = types_.find(name.type);
	if (type == types_.end()) {
	// The type has not been assigned an id yet. Ensure that the specified id is not being used by
	// another type.
	auto assign_result = type_id_finder_.ReserveId(name.type, id.type_id());
	if (!assign_result.has_value()) {
	diag->Error(DiagMessage() << "can't assign ID " << id << " to resource " << name
	<< " because type " << assign_result.error());
	return false;
	}
	type = types_.emplace(name.type, TypeGroup(package_id_, id.type_id())).first;
	}

	auto assign_result = type->second.ReserveId(name, id);
	if (!assign_result.has_value()) {
	diag->Error(DiagMessage() << "can't assign ID " << id << " to resource " << name << " because "
	<< assign_result.error());
	return false;
	}

	return true;
	}

	std::optional<ResourceId> IdAssignerContext::NextId(const ResourceName& name, IDiagnostics* diag) {
	// The package name is not known during the compile stage.
	// Resources without a package name are considered a part of the app being linked.
	CHECK(name.package.empty() \|\| name.package == package_name_);
	auto type = types_.find(name.type);
	if (type == types_.end()) {
	auto next_type_id = type_id_finder_.NextId();
	CHECK(next_type_id.has_value()) << "resource type IDs allocated have exceeded maximum (256)";
	type = types_.emplace(name.type, TypeGroup(package_id_, next_type_id.value())).first;
	}

	auto assign_result = type->second.NextId();
	if (!assign_result.has_value()) {
	diag->Error(DiagMessage() << "can't assign resource ID to resource " << name << " because "
	<< assign_result.error());
	return {};
	}
	return assign_result.value();
	}
	} // namespace

	} // namespace aapt