* errno.cc (errmap): Map ERROR_BEGINNING_OF_MEDIA and

ERROR_SETMARK_DETECTED to EIO instead of ESPIPE.
	Handle ERROR_FILEMARK_DETECTED.
	* fhandler_tape.cc (TAPE_FUNC): Add comment that ERROR_BUS_RESET
	has still to be handled correctly.
	(fhandler_dev_tape::open): Accomodate fact that get.mt_dsreg
	also contains density code.
	(fhandler_dev_tape::ioctl): Rearrange slightly.  Reset devbuf also on
	MTNOP, MTWSM, MTSETBLK, MTSETDRVBUFFER, MTSETPART and MTMKPART.
	(fhandler_dev_tape::tape_set_pos): Rearrange.  Match behaviour to
	the Linux tape driver.
	(fhandler_dev_tape::tape_status): Call IOCTL_STORAGE_GET_MEDIA_TYPES_EX
	if available.  Return device type and density code in appropriate
	mtget members.
	* wincap.h (wincaps::has_ioctl_storage_get_media_types_ex): New element.
	* wincap.cc: Implement above element throughout.
	* include/cygwin/mtio.h: Add tape device types as returned by
	IOCTL_STORAGE_GET_MEDIA_TYPES_EX.
	(MT_TAPE_INFO): Use above type codes.
	(struct mtget): Change mt_dsreg comment.

winsup/cygwin/errno.cc

@@ -102,8 +102,8 @@ static NO_COPY struct
   X (NOT_OWNER,			EPERM),
   X (END_OF_MEDIA,		ENOSPC),
   X (EOM_OVERFLOW,		ENOSPC),
-  X (BEGINNING_OF_MEDIA,	ESPIPE),
-  X (SETMARK_DETECTED,		ESPIPE),
+  X (BEGINNING_OF_MEDIA,	EIO),
+  X (SETMARK_DETECTED,		EIO),
   X (NO_DATA_DETECTED,		ENOSPC),
   X (POSSIBLE_DEADLOCK,		EDEADLOCK),
   X (CRC,			EIO),
@@ -115,6 +115,7 @@ static NO_COPY struct
   X (INVALID_ADDRESS,		EOVERFLOW),
   X (INVALID_BLOCK_LENGTH,	EIO),
   X (BUS_RESET,			EIO),
+  X (FILEMARK_DETECTED,		EIO),
   { 0, NULL, 0}
 };