Files
UnrealEngine/Engine/Source/Runtime/Serialization/Private/Backends/CborStructDeserializerBackend.cpp
2025-05-18 13:04:45 +08:00

392 lines
15 KiB
C++

// Copyright Epic Games, Inc. All Rights Reserved.
#include "Backends/CborStructDeserializerBackend.h"
#include "Backends/StructDeserializerBackendUtilities.h"
#include "StructSerializationUtilities.h"
#include "UObject/Class.h"
#include "UObject/AnsiStrProperty.h"
#include "UObject/EnumProperty.h"
#include "UObject/TextProperty.h"
#include "UObject/UnrealType.h"
#include "UObject/Utf8StrProperty.h"
FCborStructDeserializerBackend::FCborStructDeserializerBackend(FArchive& Archive, ECborEndianness CborDataEndianness, bool bInIsLWCCompatibilityMode)
: CborReader(&Archive, CborDataEndianness)
, bIsLWCCompatibilityMode(bInIsLWCCompatibilityMode)
{}
FCborStructDeserializerBackend::~FCborStructDeserializerBackend() = default;
const FString& FCborStructDeserializerBackend::GetCurrentPropertyName() const
{
return LastMapKey;
}
FString FCborStructDeserializerBackend::GetDebugString() const
{
FArchive* Ar = const_cast<FArchive*>(CborReader.GetArchive());
return FString::Printf(TEXT("Offset: %" UINT64_FMT), Ar ? Ar->Tell() : 0);
}
const FString& FCborStructDeserializerBackend::GetLastErrorMessage() const
{
// interface function that is actually entirely unused...
static FString Dummy;
return Dummy;
}
bool FCborStructDeserializerBackend::GetNextToken(EStructDeserializerBackendTokens& OutToken)
{
LastMapKey.Reset();
if (bDeserializingByteArray) // Deserializing the content of a TArray<uint8>/TArray<int8> property?
{
if (DeserializingByteArrayIndex < LastContext.AsByteArray().Num())
{
OutToken = EStructDeserializerBackendTokens::Property; // Need to consume a byte from the CBOR ByteString as a UByteProperty/UInt8Property.
}
else
{
bDeserializingByteArray = false;
OutToken = EStructDeserializerBackendTokens::ArrayEnd; // All bytes from the byte string were deserialized into the TArray<uint8>/TArray<int8>.
}
return true;
}
if (!CborReader.ReadNext(LastContext))
{
OutToken = LastContext.IsError() ? EStructDeserializerBackendTokens::Error : EStructDeserializerBackendTokens::None;
return false;
}
if (LastContext.IsBreak())
{
ECborCode ContainerEndType = LastContext.AsBreak();
// We do not support indefinite string container type
check(ContainerEndType == ECborCode::Array || ContainerEndType == ECborCode::Map);
OutToken = ContainerEndType == ECborCode::Array ? EStructDeserializerBackendTokens::ArrayEnd : EStructDeserializerBackendTokens::StructureEnd;
return true;
}
// if after reading the last context, the parent context is a map with an odd length, we just read a key
if (CborReader.GetContext().MajorType() == ECborCode::Map && (CborReader.GetContext().AsLength() & 1))
{
// Should be a string
check(LastContext.MajorType() == ECborCode::TextString);
LastMapKey = LastContext.AsString();
// Read next and carry on
if (!CborReader.ReadNext(LastContext))
{
OutToken = LastContext.IsError() ? EStructDeserializerBackendTokens::Error : EStructDeserializerBackendTokens::None;
return false;
}
}
switch (LastContext.MajorType())
{
case ECborCode::Array:
OutToken = EStructDeserializerBackendTokens::ArrayStart;
break;
case ECborCode::Map:
OutToken = EStructDeserializerBackendTokens::StructureStart;
break;
case ECborCode::ByteString: // Used for size optimization on TArray<uint8>/TArray<int8>. Might be replaced if https://datatracker.ietf.org/doc/draft-ietf-cbor-array-tags/ is adopted.
OutToken = EStructDeserializerBackendTokens::ArrayStart;
DeserializingByteArrayIndex = 0;
bDeserializingByteArray = true;
break;
case ECborCode::Int:
// fall through
case ECborCode::Uint:
// fall through
case ECborCode::TextString:
// fall through
case ECborCode::Prim:
OutToken = EStructDeserializerBackendTokens::Property;
break;
default:
// Other types are unsupported
check(false);
}
return true;
}
bool FCborStructDeserializerBackend::ReadProperty(FProperty* Property, FProperty* Outer, void* Data, int32 ArrayIndex)
{
switch (LastContext.MajorType())
{
// Unsigned Integers
case ECborCode::Uint:
{
if (FByteProperty* ByteProperty = CastField<FByteProperty>(Property))
{
return StructDeserializerBackendUtilities::SetPropertyValue(ByteProperty, Outer, Data, ArrayIndex, (uint8)LastContext.AsUInt());
}
if (FUInt16Property* FInt16Property = CastField<FUInt16Property>(Property))
{
return StructDeserializerBackendUtilities::SetPropertyValue(FInt16Property, Outer, Data, ArrayIndex, (uint16)LastContext.AsUInt());
}
if (FUInt32Property* UInt32Property = CastField<FUInt32Property>(Property))
{
return StructDeserializerBackendUtilities::SetPropertyValue(UInt32Property, Outer, Data, ArrayIndex, (uint32)LastContext.AsUInt());
}
if (FUInt64Property* FInt64Property = CastField<FUInt64Property>(Property))
{
return StructDeserializerBackendUtilities::SetPropertyValue(FInt64Property, Outer, Data, ArrayIndex, (uint64)LastContext.AsUInt());
}
}
// Fall through - cbor can encode positive signed integers as unsigned
// Signed Integers
case ECborCode::Int:
{
if (FInt8Property* Int8Property = CastField<FInt8Property>(Property))
{
return StructDeserializerBackendUtilities::SetPropertyValue(Int8Property, Outer, Data, ArrayIndex, (int8)LastContext.AsInt());
}
if (FInt16Property* Int16Property = CastField<FInt16Property>(Property))
{
return StructDeserializerBackendUtilities::SetPropertyValue(Int16Property, Outer, Data, ArrayIndex, (int16)LastContext.AsInt());
}
if (FIntProperty* IntProperty = CastField<FIntProperty>(Property))
{
return StructDeserializerBackendUtilities::SetPropertyValue(IntProperty, Outer, Data, ArrayIndex, (int32)LastContext.AsInt());
}
if (FInt64Property* Int64Property = CastField<FInt64Property>(Property))
{
return StructDeserializerBackendUtilities::SetPropertyValue(Int64Property, Outer, Data, ArrayIndex, (int64)LastContext.AsInt());
}
UE_LOG(LogSerialization, Verbose, TEXT("Integer field %s with value '%" UINT64_FMT "' is not supported in FProperty type %s (%s)"), *Property->GetFName().ToString(), LastContext.AsUInt(), *Property->GetClass()->GetName(), *GetDebugString());
return false;
}
// Strings, Names, Enumerations & Object/Class reference
case ECborCode::TextString:
{
if (FAnsiStrProperty* AnsiStrProperty = CastField<FAnsiStrProperty>(Property))
{
return StructDeserializerBackendUtilities::SetPropertyValue(AnsiStrProperty, Outer, Data, ArrayIndex, LastContext.AsAnsiString());
}
if (FUtf8StrProperty* Utf8StrProperty = CastField<FUtf8StrProperty>(Property))
{
return StructDeserializerBackendUtilities::SetPropertyValue(Utf8StrProperty, Outer, Data, ArrayIndex, LastContext.AsUtf8String());
}
FString StringValue = LastContext.AsString();
if (FStrProperty* StrProperty = CastField<FStrProperty>(Property))
{
return StructDeserializerBackendUtilities::SetPropertyValue(StrProperty, Outer, Data, ArrayIndex, StringValue);
}
if (FNameProperty* NameProperty = CastField<FNameProperty>(Property))
{
return StructDeserializerBackendUtilities::SetPropertyValue(NameProperty, Outer, Data, ArrayIndex, FName(*StringValue));
}
if (FTextProperty* TextProperty = CastField<FTextProperty>(Property))
{
FText TextValue;
if (!FTextStringHelper::ReadFromBuffer(*StringValue, TextValue))
{
TextValue = FText::FromString(StringValue);
}
return StructDeserializerBackendUtilities::SetPropertyValue(TextProperty, Outer, Data, ArrayIndex, TextValue);
}
if (FByteProperty* ByteProperty = CastField<FByteProperty>(Property))
{
if (!ByteProperty->Enum)
{
return false;
}
int64 Value = ByteProperty->Enum->GetValueByName(*StringValue);
if (Value == INDEX_NONE)
{
return false;
}
return StructDeserializerBackendUtilities::SetPropertyValue(ByteProperty, Outer, Data, ArrayIndex, (uint8)Value);
}
if (FEnumProperty* EnumProperty = CastField<FEnumProperty>(Property))
{
int64 Value = EnumProperty->GetEnum()->GetValueByName(*StringValue);
if (Value == INDEX_NONE)
{
return false;
}
if (void* ElementPtr = StructDeserializerBackendUtilities::GetPropertyValuePtr(EnumProperty, Outer, Data, ArrayIndex))
{
EnumProperty->GetUnderlyingProperty()->SetIntPropertyValue(ElementPtr, Value);
return true;
}
return false;
}
if (FClassProperty* ClassProperty = CastField<FClassProperty>(Property))
{
return StructDeserializerBackendUtilities::SetPropertyValue(ClassProperty, Outer, Data, ArrayIndex, LoadObject<UClass>(NULL, *StringValue, NULL, LOAD_NoWarn));
}
if (FSoftClassProperty* SoftClassProperty = CastField<FSoftClassProperty>(Property))
{
return StructDeserializerBackendUtilities::SetPropertyValue(SoftClassProperty, Outer, Data, ArrayIndex, FSoftObjectPtr(FSoftObjectPath(StringValue)));
}
if (FObjectProperty* ObjectProperty = CastField<FObjectProperty>(Property))
{
return StructDeserializerBackendUtilities::SetPropertyValue(ObjectProperty, Outer, Data, ArrayIndex, StaticFindObject(ObjectProperty->PropertyClass, nullptr, *StringValue));
}
if (FWeakObjectProperty* WeakObjectProperty = CastField<FWeakObjectProperty>(Property))
{
return StructDeserializerBackendUtilities::SetPropertyValue(WeakObjectProperty, Outer, Data, ArrayIndex, FWeakObjectPtr(StaticFindObject(WeakObjectProperty->PropertyClass, nullptr, *StringValue)));
}
if (FSoftObjectProperty* SoftObjectProperty = CastField<FSoftObjectProperty>(Property))
{
return StructDeserializerBackendUtilities::SetPropertyValue(SoftObjectProperty, Outer, Data, ArrayIndex, FSoftObjectPtr(FSoftObjectPath(StringValue)));
}
UE_LOG(LogSerialization, Verbose, TEXT("String field %s with value '%s' is not supported in FProperty type %s (%s)"), *Property->GetFName().ToString(), *StringValue, *Property->GetClass()->GetName(), *GetDebugString());
return false;
}
// Stream of bytes: Used for TArray<uint8>/TArray<int8>
case ECborCode::ByteString:
{
check(bDeserializingByteArray);
// Consume one byte from the byte string.
TArrayView<const uint8> DeserializedByteArray = LastContext.AsByteArray();
check(DeserializingByteArrayIndex < DeserializedByteArray.Num());
uint8 ByteValue = DeserializedByteArray[DeserializingByteArrayIndex++];
if (FByteProperty* ByteProperty = CastField<FByteProperty>(Property))
{
return StructDeserializerBackendUtilities::SetPropertyValue(ByteProperty, Outer, Data, ArrayIndex, ByteValue);
}
else if (FInt8Property* Int8Property = CastField<FInt8Property>(Property))
{
return StructDeserializerBackendUtilities::SetPropertyValue(Int8Property, Outer, Data, ArrayIndex, (int8)ByteValue);
}
UE_LOG(LogSerialization, Verbose, TEXT("Error while deserializing field %s. Unexpected UProperty type %s. Expected a UByteProperty/UInt8Property to deserialize a TArray<uint8>/TArray<int8>"), *Property->GetFName().ToString(), *Property->GetClass()->GetName());
return false;
}
// Prim
case ECborCode::Prim:
{
switch (LastContext.AdditionalValue())
{
// Boolean
case ECborCode::True:
// fall through
case ECborCode::False:
{
const FCoreTexts& CoreTexts = FCoreTexts::Get();
if (FBoolProperty* BoolProperty = CastField<FBoolProperty>(Property))
{
return StructDeserializerBackendUtilities::SetPropertyValue(BoolProperty, Outer, Data, ArrayIndex, LastContext.AsBool());
}
UE_LOG(LogSerialization, Verbose, TEXT("Boolean field %s with value '%s' is not supported in FProperty type %s (%s)"), *Property->GetFName().ToString(), LastContext.AsBool() ? *(CoreTexts.True.ToString()) : *(CoreTexts.False.ToString()), *Property->GetClass()->GetName(), *GetDebugString());
return false;
}
// Null
case ECborCode::Null:
return StructDeserializerBackendUtilities::ClearPropertyValue(Property, Outer, Data, ArrayIndex);
// Float
case ECborCode::Value_4Bytes:
if (bIsLWCCompatibilityMode == true && StructSerializationUtilities::IsLWCType(Property->GetOwnerStruct()))
{
FDoubleProperty* DoubleProperty = CastField<FDoubleProperty>(Property);
if (ensureMsgf(DoubleProperty, TEXT("Float field %s with value '%f' from LWC struct type '%s' was expected to be a DoubleProperty but was of type %s (%s)"), *Property->GetFName().ToString(), LastContext.AsFloat(), *Property->GetOwnerStruct()->GetName(), * Property->GetClass()->GetName(), *GetDebugString()))
{
const double DoubleValue = LastContext.AsFloat();
return StructDeserializerBackendUtilities::SetPropertyValue(DoubleProperty, Outer, Data, ArrayIndex, DoubleValue);
}
}
else if(FFloatProperty* FloatProperty = CastField<FFloatProperty>(Property))
{
return StructDeserializerBackendUtilities::SetPropertyValue(FloatProperty, Outer, Data, ArrayIndex, LastContext.AsFloat());
}
UE_LOG(LogSerialization, Verbose, TEXT("Float field %s with value '%f' is not supported in FProperty type %s (%s)"), *Property->GetFName().ToString(), LastContext.AsFloat(), *Property->GetClass()->GetName(), *GetDebugString());
return false;
// Double
case ECborCode::Value_8Bytes:
if (FDoubleProperty* DoubleProperty = CastField<FDoubleProperty>(Property))
{
return StructDeserializerBackendUtilities::SetPropertyValue(DoubleProperty, Outer, Data, ArrayIndex, LastContext.AsDouble());
}
UE_LOG(LogSerialization, Verbose, TEXT("Double field %s with value '%f' is not supported in FProperty type %s (%s)"), *Property->GetFName().ToString(), LastContext.AsDouble(), *Property->GetClass()->GetName(), *GetDebugString());
return false;
default:
UE_LOG(LogSerialization, Verbose, TEXT("Unsupported primitive type for %s with value '%f' in FProperty type %s (%s)"), *Property->GetFName().ToString(), LastContext.AsDouble(), *Property->GetClass()->GetName(), *GetDebugString());
return false;
}
}
}
return true;
}
bool FCborStructDeserializerBackend::ReadPODArray(FArrayProperty* ArrayProperty, void* Data)
{
// if we just read a byte array, copy the full array if the inner property is of the appropriate type
if (bDeserializingByteArray
&& (CastField<FByteProperty>(ArrayProperty->Inner) || CastField<FInt8Property>(ArrayProperty->Inner)))
{
FScriptArrayHelper ArrayHelper(ArrayProperty, ArrayProperty->template ContainerPtrToValuePtr<void>(Data));
TArrayView<const uint8> DeserializedByteArray = LastContext.AsByteArray();
if (DeserializedByteArray.Num())
{
ArrayHelper.AddUninitializedValues(DeserializedByteArray.Num());
void* ArrayStart = ArrayHelper.GetRawPtr();
FMemory::Memcpy(ArrayStart, DeserializedByteArray.GetData(), DeserializedByteArray.Num());
}
bDeserializingByteArray = false;
return true;
}
return false;
}
void FCborStructDeserializerBackend::SkipArray()
{
if (bDeserializingByteArray) // Deserializing a TArray<uint8>/TArray<int8> property as byte string?
{
check(DeserializingByteArrayIndex == 0);
bDeserializingByteArray = false;
}
else
{
CborReader.SkipContainer(ECborCode::Array);
}
}
void FCborStructDeserializerBackend::SkipStructure()
{
CborReader.SkipContainer(ECborCode::Map);
}