Reduce copying & memory allocation by writing directly into function argument instead of allocating & copying (#38846)

Author: gmarcosb

src/app/SafeAttributePersistenceProvider.h

@@ -71,7 +71,7 @@ class SafeAttributePersistenceProvider
      * Read an attribute of type intX, uintX or bool from non-volatile memory.
      *
      * @param [in]     aPath the attribute path for the data being persisted.
-     * @param [in,out] aValue where to place the data.
+     * @param [out]    aValue where to place the data.
      *
      * @retval CHIP_ERROR_PERSISTED_STORAGE_VALUE_NOT_FOUND if no stored value exists for the attribute
      */
@@ -112,7 +112,7 @@ class SafeAttributePersistenceProvider
      * Read an attribute of type nullable intX, uintX from non-volatile memory.
      *
      * @param [in]     aPath the attribute path for the data being persisted.
-     * @param [in,out] aValue where to place the data.
+     * @param [out]    aValue where to place the data.
      *
      * @retval CHIP_ERROR_PERSISTED_STORAGE_VALUE_NOT_FOUND if no stored value exists for the attribute
      */

src/app/clusters/scenes-server/SceneTable.h

@@ -20,7 +20,6 @@
 #include <app/clusters/scenes-server/ExtensionFieldSets.h>
 #include <app/storage/TableEntry.h>
 #include <lib/support/CHIPMemString.h>
-#include <lib/support/CommonIterator.h>
 #include <lib/support/IntrusiveList.h>
 #include <lib/support/PersistentData.h>
 #include <lib/support/Span.h>
@@ -233,7 +232,7 @@ class SceneTable
 
     SceneTable & operator=(const SceneTable &) = delete;
 
-    virtual CHIP_ERROR Init(PersistentStorageDelegate * storage) = 0;
+    virtual CHIP_ERROR Init(PersistentStorageDelegate & storage) = 0;
     virtual void Finish()                                        = 0;
 
     // Global scene count

src/app/clusters/scenes-server/SceneTableImpl.cpp

@@ -48,7 +48,7 @@ StorageKeyName Serializer::FabricEntryDataKey(FabricIndex fabric, EndpointId end
 
 // Worst case tested: Add Scene Command with EFS using the default SerializeAdd Method. This yielded a serialized scene of 175 bytes
 // when using the OnOff, Level Control and Color Control as well as the maximal name length of 16 bytes. Putting 256 gives some
-// slack in case different clusters are used. Value obtained by using writer.GetLengthWritten at the end of the SceneTableData
+// slack in case different clusters are used. Value obtained by using writer.GetLengthWritten at the end of the Serializer
 // Serialize method.
 template <>
 constexpr size_t Serializer::kEntryMaxBytes()
@@ -83,7 +83,7 @@ namespace {
 /// kGroupId: Tag for GroupID if the Scene is a Group Scene
 /// kSceneId: Tag for the scene ID. Together with kGroupId, forms the SceneStorageId
 /// kName: Tag for the name of the scene
-/// kTransitionTime: Tag for the transition time of the scene in miliseconds
+/// kTransitionTime: Tag for the transition time of the scene in milliseconds
 enum class TagScene : uint8_t
 {
     kGroupId = static_cast<uint8_t>(TagEntry::kFabricTableFirstSpecializationReservedTag),
@@ -93,13 +93,12 @@ enum class TagScene : uint8_t
 };
 } // namespace
 
-using SceneTableData = TableEntryData<SceneStorageId, SceneData, Serializer::kEntryMaxBytes()>;
 using FabricSceneData =
     FabricEntryData<SceneStorageId, SceneData, Serializer::kEntryMaxBytes(), Serializer::kFabricMaxBytes(), kMaxScenesPerFabric>;
 
 template class chip::app::Storage::FabricTableImpl<SceneTableBase::SceneStorageId, SceneTableBase::SceneData, kIteratorsMax>;
 
-CHIP_ERROR DefaultSceneTableImpl::Init(PersistentStorageDelegate * storage)
+CHIP_ERROR DefaultSceneTableImpl::Init(PersistentStorageDelegate & storage)
 {
     return FabricTableImpl::Init(storage);
 }
@@ -156,7 +155,6 @@ CHIP_ERROR DefaultSceneTableImpl::GetAllSceneIdsInGroup(FabricIndex fabric_index
     VerifyOrReturnError(IsInitialized(), CHIP_ERROR_INTERNAL);
 
     FabricSceneData fabric(mEndpointId, fabric_index, mMaxPerFabric, mMaxPerEndpoint);
-    SceneTableData scene(mEndpointId, fabric_index);
 
     uint8_t scene_count = 0;
     CHIP_ERROR err      = fabric.Load(this->mStorage);
@@ -190,7 +188,6 @@ CHIP_ERROR DefaultSceneTableImpl::DeleteAllScenesInGroup(FabricIndex fabric_inde
     VerifyOrReturnError(IsInitialized(), CHIP_ERROR_INTERNAL);
 
     FabricSceneData fabric(mEndpointId, fabric_index, mMaxPerFabric, mMaxPerEndpoint);
-    SceneTableData scene(mEndpointId, fabric_index);
 
     CHIP_ERROR err = fabric.Load(this->mStorage);
     VerifyOrReturnValue(CHIP_ERROR_NOT_FOUND != err, CHIP_NO_ERROR);

src/app/clusters/scenes-server/SceneTableImpl.h

@@ -23,7 +23,6 @@
 #include <app/util/attribute-storage.h>
 #include <app/util/config.h>
 #include <lib/core/DataModelTypes.h>
-#include <lib/support/CommonIterator.h>
 #include <lib/support/PersistentData.h>
 #include <lib/support/Pool.h>
 
@@ -61,7 +60,7 @@ class DefaultSceneTableImpl
     DefaultSceneTableImpl() : Super(kMaxScenesPerFabric, kMaxScenesPerEndpoint) {}
     ~DefaultSceneTableImpl() { Finish(); };
 
-    CHIP_ERROR Init(PersistentStorageDelegate * storage) override;
+    CHIP_ERROR Init(PersistentStorageDelegate & storage) override;
     void Finish() override;
 
     // Scene count

src/app/clusters/scenes-server/scenes-server.cpp

@@ -333,7 +333,7 @@ CHIP_ERROR ScenesServer::Init()
     mGroupProvider = Credentials::GetGroupDataProvider();
 
     SceneTable * sceneTable = scenes::GetSceneTableImpl();
-    ReturnErrorOnFailure(sceneTable->Init(&Server::GetInstance().GetPersistentStorage()));
+    ReturnErrorOnFailure(sceneTable->Init(Server::GetInstance().GetPersistentStorage()));
     ReturnErrorOnFailure(Server::GetInstance().GetFabricTable().AddFabricDelegate(&gFabricDelegate));
 
     mIsInitialized = true;

src/app/icd/server/ICDMonitoringTable.cpp

@@ -30,7 +30,7 @@ enum class Fields : uint8_t
     kClientType       = 5,
 };
 
-CHIP_ERROR ICDMonitoringEntry::UpdateKey(StorageKeyName & skey)
+CHIP_ERROR ICDMonitoringEntry::UpdateKey(StorageKeyName & skey) const
 {
     VerifyOrReturnError(kUndefinedFabricIndex != this->fabricIndex, CHIP_ERROR_INVALID_FABRIC_INDEX);
     skey = DefaultStorageKeyAllocator::ICDManagementTableEntry(this->fabricIndex, index);

src/app/icd/server/ICDMonitoringTable.h

@@ -68,7 +68,7 @@ struct ICDMonitoringEntry : public PersistentData<kICDMonitoringBufferSize>
         this->symmetricKeystore = keyStore;
     }
 
-    CHIP_ERROR UpdateKey(StorageKeyName & key) override;
+    CHIP_ERROR UpdateKey(StorageKeyName & key) const override;
     CHIP_ERROR Serialize(TLV::TLVWriter & writer) const override;
     CHIP_ERROR Deserialize(TLV::TLVReader & reader) override;
     void Clear() override;

src/app/storage/FabricTableImpl.h

@@ -17,6 +17,9 @@
 
 #pragma once
 
+#include <app/storage/TableEntry.h>
+#include <lib/support/CommonIterator.h>
+#include <lib/support/PersistentData.h>
 #include <lib/support/TypeTraits.h>
 
 namespace chip {
@@ -41,7 +44,7 @@ class FabricTableImpl
 public:
     virtual ~FabricTableImpl() { Finish(); };
 
-    CHIP_ERROR Init(PersistentStorageDelegate * storage);
+    CHIP_ERROR Init(PersistentStorageDelegate & storage);
     void Finish();
 
     // Entry count