protected override async Task <FileMetadata> GetFileMetadataImplAsync(string path, FileMetadataGetFlags flags = FileMetadataGetFlags.DefaultAll, CancellationToken cancel = default)
{
FileMetadata physicalMetadata = await UnderlayFileSystem.GetFileMetadataAsync(path, flags, cancel);
try
{
long headerOffset = 0;
long physicalSize = physicalMetadata.Size;
using (FileObject physicalFile = await UnderlayFileSystem.OpenAsync(path))
{
byte[] bomRead = new byte[3];
Memory <byte> tmp = new byte[3];
if (await physicalFile.ReadRandomAsync(0, tmp, cancel) == tmp.Length)
{
if (tmp.Span.SequenceEqual(Str.BOM_UTF_8.Span))
{
headerOffset = 3;
}
}
physicalSize = await physicalFile.GetFileSizeAsync(true, cancel) - headerOffset;
if (physicalSize >= 0)
{
physicalMetadata.Size = physicalSize;
}
}
}
catch { }
return(physicalMetadata);
}
protected override async Task <FileMetadata> GetFileMetadataImplAsync(string path, FileMetadataGetFlags flags = FileMetadataGetFlags.DefaultAll, CancellationToken cancel = default)
{
// Try physical file first
try
{
return(await UnderlayFileSystem.GetFileMetadataAsync(path, flags, cancel));
}
catch { }
LargeFileSystem.ParsedPath[] physicalFiles = await GetPhysicalFileStateInternal(path, cancel);
var lastFileParsed = physicalFiles.OrderBy(x => x.FileNumber).LastOrDefault();
if (lastFileParsed == null)
{
// File not found
throw new IOException($"The file '{path}' not found.");
}
else
{
// Large file exists
checked
{
FileMetadata ret = await UnderlayFileSystem.GetFileMetadataAsync(lastFileParsed.PhysicalFilePath, flags | FileMetadataGetFlags.NoSecurity | FileMetadataGetFlags.NoAlternateStream, cancel);
long sizeOfLastFile = ret.Size;
sizeOfLastFile = Math.Min(sizeOfLastFile, Params.MaxSinglePhysicalFileSize);
long currentFileSize = lastFileParsed.FileNumber * Params.MaxSinglePhysicalFileSize + sizeOfLastFile;
ret.Size = currentFileSize;
ret.PhysicalSize = physicalFiles.Sum(x => x.PhysicalEntity !.PhysicalSize);
ret.CreationTime = physicalFiles.Min(x => x.PhysicalEntity !.CreationTime);
ret.LastWriteTime = physicalFiles.Max(x => x.PhysicalEntity !.LastWriteTime);
ret.LastAccessTime = physicalFiles.Max(x => x.PhysicalEntity !.LastAccessTime);
return(ret);
}
}
}