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);
}