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

121 lines
3.9 KiB
C++

// Copyright Epic Games, Inc. All Rights Reserved.
#include "RuntimeAssetCacheFilesystemBackend.h"
#include "GenericPlatform/GenericPlatformFile.h"
#include "HAL/FileManager.h"
#include "Misc/Paths.h"
#include "Misc/ConfigCacheIni.h"
#include "RuntimeAssetCacheBucket.h"
#include "RuntimeAssetCacheEntryMetadata.h"
FArchive* FRuntimeAssetCacheFilesystemBackend::CreateReadArchive(FName Bucket, const TCHAR* CacheKey)
{
FString Path = FPaths::Combine(*PathToRAC, *Bucket.ToString(), CacheKey);
return IFileManager::Get().CreateFileReader(*Path);
}
FArchive* FRuntimeAssetCacheFilesystemBackend::CreateWriteArchive(FName Bucket, const TCHAR* CacheKey)
{
FString Path = FPaths::Combine(*PathToRAC, *Bucket.ToString(), CacheKey);
return IFileManager::Get().CreateFileWriter(*Path);
}
FRuntimeAssetCacheFilesystemBackend::FRuntimeAssetCacheFilesystemBackend()
{
GConfig->GetString(TEXT("RuntimeAssetCache"), TEXT("PathToRAC"), PathToRAC, GEngineIni);
PathToRAC = FPaths::ProjectSavedDir() / PathToRAC;
}
bool FRuntimeAssetCacheFilesystemBackend::RemoveCacheEntry(const FName Bucket, const TCHAR* CacheKey)
{
FString Path = FPaths::Combine(*PathToRAC, *Bucket.ToString(), CacheKey);
return IFileManager::Get().Delete(*Path);
}
bool FRuntimeAssetCacheFilesystemBackend::ClearCache()
{
return IFileManager::Get().DeleteDirectory(*PathToRAC, false, true);
}
bool FRuntimeAssetCacheFilesystemBackend::ClearCache(FName Bucket)
{
if (Bucket != NAME_None)
{
return IFileManager::Get().DeleteDirectory(*FPaths::Combine(*PathToRAC, *Bucket.ToString()), false, true);
}
return false;
}
FRuntimeAssetCacheBucket* FRuntimeAssetCacheFilesystemBackend::PreLoadBucket(FName BucketName, int32 BucketSize)
{
FString Path = FPaths::Combine(*PathToRAC, *BucketName.ToString());
FRuntimeAssetCacheBucket* Result = new FRuntimeAssetCacheBucket(BucketSize);
class FRuntimeAssetCacheFilesystemBackendDirectoryVisitor : public IPlatformFile::FDirectoryVisitor
{
public:
FRuntimeAssetCacheFilesystemBackendDirectoryVisitor(FRuntimeAssetCacheBucket* InBucket, FName InBucketName, FRuntimeAssetCacheFilesystemBackend* InBackend)
: Bucket(InBucket)
, BucketName(InBucketName)
, Backend(InBackend)
{ }
virtual bool Visit(const TCHAR* FilenameOrDirectory, bool bIsDirectory)
{
if (bIsDirectory)
{
return true;
}
FString CacheKey = FPaths::GetBaseFilename(FilenameOrDirectory);
FArchive* Ar = Backend->CreateReadArchive(BucketName, *CacheKey);
FCacheEntryMetadata* Metadata = Backend->PreloadMetadata(Ar);
Files.Add(TFilenameMetadataPair(*FPaths::GetBaseFilename(FilenameOrDirectory), Metadata));
delete Ar;
return true;
}
void Finalize()
{
Files.Sort([](const TFilenameMetadataPair& A, const TFilenameMetadataPair& B) { return A.Get<1>()->GetLastAccessTime() > B.Get<1>()->GetLastAccessTime(); });
int32 CurrentFileIndex = 0;
for (; CurrentFileIndex < Files.Num(); ++CurrentFileIndex)
{
FName Name = Files[CurrentFileIndex].Get<0>();
FCacheEntryMetadata* Metadata = Files[CurrentFileIndex].Get<1>();
if ((Bucket->GetCurrentSize() + Metadata->GetCachedAssetSize()) <= Bucket->GetSize())
{
Bucket->AddMetadataEntry(Name.ToString(), Metadata, true);
}
else
{
// No space left. Stop adding entries to the bucket, and all the rest of the older files
break;
}
}
for (; CurrentFileIndex < Files.Num(); ++CurrentFileIndex)
{
FName Name = Files[CurrentFileIndex].Get<0>();
FCacheEntryMetadata* Metadata = Files[CurrentFileIndex].Get<1>();
Backend->RemoveCacheEntry(BucketName, *Name.ToString());
delete Metadata;
}
}
private:
FRuntimeAssetCacheBucket* Bucket;
FName BucketName;
FRuntimeAssetCacheFilesystemBackend* Backend;
typedef TTuple<FName, FCacheEntryMetadata*> TFilenameMetadataPair;
TArray<TFilenameMetadataPair> Files;
} Visitor(Result, BucketName, this);
IFileManager::Get().IterateDirectory(*Path, Visitor);
Visitor.Finalize();
return Result;
}