public void Seek(long dlibMove, STREAM_SEEK dwOrigin, IntPtr plibNewPosition)
{
SeekOrigin seekOrigin;
switch (dwOrigin)
{
case STREAM_SEEK.STREAM_SEEK_SET:
seekOrigin = SeekOrigin.Begin;
break;
case STREAM_SEEK.STREAM_SEEK_CUR:
seekOrigin = SeekOrigin.Current;
break;
case STREAM_SEEK.STREAM_SEEK_END:
seekOrigin = SeekOrigin.End;
break;
default:
throw new ArgumentOutOfRangeException(nameof(dwOrigin));
}
long newPosition = UnderlyingStream.Seek(dlibMove, seekOrigin);
if (plibNewPosition != IntPtr.Zero)
{
Marshal.WriteInt64(plibNewPosition, 0, newPosition);
}
}
int IStream.Seek(long dlibMove, STREAM_SEEK dwOrigin, IntPtr plibNewPosition)
{
SeekOrigin origin;
switch (dwOrigin)
{
case STREAM_SEEK.STREAM_SEEK_SET:
origin = SeekOrigin.Begin;
break;
case STREAM_SEEK.STREAM_SEEK_CUR:
origin = SeekOrigin.Current;
break;
case STREAM_SEEK.STREAM_SEEK_END:
origin = SeekOrigin.End;
break;
default:
return(STG_E_INVALIDFUNCTION);
}
if (plibNewPosition != IntPtr.Zero)
{
Marshal.WriteInt64(plibNewPosition, stream.Seek(dlibMove, origin));
}
return(S_OK);
}
public static void Seek(this IStream stream, long dlibMove, STREAM_SEEK dwOrigin, out long plibNewPosition)
{
var plibNewPositionPtr = Marshal.AllocCoTaskMem(8);
try
{
stream.Seek(dlibMove, dwOrigin, plibNewPositionPtr);
plibNewPosition = Marshal.ReadInt64(plibNewPositionPtr, 0);
}
finally
{
Marshal.FreeCoTaskMem(plibNewPositionPtr);
}
}
public unsafe void Seek(long dlibMove, STREAM_SEEK dwOrigin, ulong *plibNewPosition = default)
{
var seekOrigin = dwOrigin switch
{
STREAM_SEEK.STREAM_SEEK_SET => SeekOrigin.Begin,
STREAM_SEEK.STREAM_SEEK_CUR => SeekOrigin.Current,
STREAM_SEEK.STREAM_SEEK_END => SeekOrigin.End,
_ => throw new ArgumentOutOfRangeException(nameof(dwOrigin))
};
var newPosition = _baseStream.Seek(dlibMove, seekOrigin);
if (plibNewPosition is not null)
{
Marshal.WriteInt64(new IntPtr(plibNewPosition), newPosition);
}
}
internal static int Seek(this IStream stream, long dlibMove, STREAM_SEEK dwOrigin)
{
IntPtr plibNewPosition = default(IntPtr);
return(stream.Seek(dlibMove, (int)dwOrigin, plibNewPosition));
}
int IStream.Seek(long dlibMove, STREAM_SEEK dwOrigin, IntPtr plibNewPosition)
{
SeekOrigin origin;
switch (dwOrigin)
{
case STREAM_SEEK.STREAM_SEEK_SET:
origin = SeekOrigin.Begin;
break;
case STREAM_SEEK.STREAM_SEEK_CUR:
origin = SeekOrigin.Current;
break;
case STREAM_SEEK.STREAM_SEEK_END:
origin = SeekOrigin.End;
break;
default:
return STG_E_INVALIDFUNCTION;
}
if (plibNewPosition != IntPtr.Zero)
Marshal.WriteInt64(plibNewPosition, stream.Seek(dlibMove, origin));
return S_OK;
}
public static void Seek(this IStream stream, long dlibMove, STREAM_SEEK dwOrigin)
{
stream.Seek(dlibMove, dwOrigin, IntPtr.Zero);
}