private long _appendStart; // When appending, prevent overwriting file.
internal OSFileStreamStrategy(SafeFileHandle handle, FileAccess access)
{
_access = access;
handle.EnsureThreadPoolBindingInitialized();
if (handle.CanSeek)
{
// given strategy was created out of existing handle, so we have to perform
// a syscall to get the current handle offset
_filePosition = FileStreamHelpers.Seek(handle, 0, SeekOrigin.Current);
}
else
{
_filePosition = 0;
}
_fileHandle = handle;
}
private bool _exposedHandle; // created from handle, or SafeFileHandle was used and the handle got exposed
internal WindowsFileStreamStrategy(SafeFileHandle handle, FileAccess access, FileShare share)
{
_access = access;
_share = share;
_exposedHandle = true;
handle.InitThreadPoolBindingIfNeeded();
if (handle.CanSeek)
{
// given strategy was created out of existing handle, so we have to perform
// a syscall to get the current handle offset
_filePosition = FileStreamHelpers.Seek(handle, _path, 0, SeekOrigin.Current);
}
else
{
_filePosition = 0;
}
_fileHandle = handle;
}
// This doesn't do argument checking. Necessary for SetLength, which must
// set the file pointer beyond the end of the file. This will update the
// internal position
private long SeekCore(SafeFileHandle fileHandle, long offset, SeekOrigin origin, bool closeInvalidHandle = false)
{
Debug.Assert(fileHandle.CanSeek, "fileHandle.CanSeek");
return(_filePosition = FileStreamHelpers.Seek(fileHandle, offset, origin, closeInvalidHandle));
}
// This doesn't do argument checking. Necessary for SetLength, which must
// set the file pointer beyond the end of the file. This will update the
// internal position
protected long SeekCore(SafeFileHandle fileHandle, long offset, SeekOrigin origin, bool closeInvalidHandle = false)
{
Debug.Assert(!fileHandle.IsClosed && _canSeek, "!fileHandle.IsClosed && _canSeek");
return(_filePosition = FileStreamHelpers.Seek(fileHandle, _path, offset, origin, closeInvalidHandle));
}