[newlib-cygwin] Add _IOC_NEWLEN() and _IOC_NEWTYPE() macros.

[Sebastian Huber <sh@sourceware.org>]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=4d144963ea0149c6a4bd8a9c2aec4ce740dad9d5

commit 4d144963ea0149c6a4bd8a9c2aec4ce740dad9d5
Author: brooks <brooks@FreeBSD.org>
Date:   Fri Mar 16 22:23:04 2018 +0000

    Add _IOC_NEWLEN() and _IOC_NEWTYPE() macros.
    
    These macros take an existing ioctl(2) command and replace the length
    with the specified length or length of the specified type respectively.
    These can be used to define commands for 32-bit compatibility with fewer
    opportunities for cut-and-paste errors then a whole new definition.
    
    Reviewed by:	cem, kib
    Obtained from:	CheriBSD
    Sponsored by:	DARPA, AFRL
    Differential Revision:	https://reviews.freebsd.org/D14706

Diff:
---
 newlib/libc/sys/rtems/include/sys/ioccom.h | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/newlib/libc/sys/rtems/include/sys/ioccom.h b/newlib/libc/sys/rtems/include/sys/ioccom.h
index 34ea1e1..2a8416c 100644
--- a/newlib/libc/sys/rtems/include/sys/ioccom.h
+++ b/newlib/libc/sys/rtems/include/sys/ioccom.h
@@ -68,6 +68,10 @@ typedef unsigned long ioctl_command_t;
 #define	_IOW(g,n,t)	_IOC(IOC_IN,	(g), (n), sizeof(t))
 /* this should be _IORW, but stdio got there first */
 #define	_IOWR(g,n,t)	_IOC(IOC_INOUT,	(g), (n), sizeof(t))
+/* Replace length/type in an ioctl command. */
+#define	_IOC_NEWLEN(ioc, len) \
+    (((~(IOCPARM_MASK << 16)) & (ioc)) | (((len) & IOCPARM_MASK) << 16))
+#define	_IOC_NEWTYPE(ioc, type)	_IOC_NEWLEN((ioc), sizeof(type))
 
 #ifdef _KERNEL