[newlib-cygwin] Implement read(2)/write(2) and neccessary lseek(2)

[newlib-cygwin] Implement read(2)/write(2) and neccessary lseek(2)

[Sebastian Huber]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=e6a85661cee799cd51c2afff4d6d5ec54d3e8a43

commit e6a85661cee799cd51c2afff4d6d5ec54d3e8a43
Author: kib <kib@FreeBSD.org>
Date:   Wed Aug 21 17:45:00 2013 +0000

    Implement read(2)/write(2) and neccessary lseek(2)
    
    for posix shmfd. Add MAC framework entries for posix shm read and write.
    
    Do not allow implicit extension of the underlying memory segment past
    the limit set by ftruncate(2) by either of the syscalls.  Read and
    write returns short i/o, lseek(2) fails with EINVAL when resulting
    offset does not fit into the limit.
    
    Discussed with:	alc
    Tested by:	pho
    Sponsored by:	The FreeBSD Foundation

Diff:
---
 newlib/libc/sys/rtems/include/sys/mman.h | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/newlib/libc/sys/rtems/include/sys/mman.h b/newlib/libc/sys/rtems/include/sys/mman.h
index e7e5cf4..536bfd5 100644
--- a/newlib/libc/sys/rtems/include/sys/mman.h
+++ b/newlib/libc/sys/rtems/include/sys/mman.h
@@ -190,6 +190,10 @@ typedef	__size_t	size_t;
 #endif
 
 #if defined(_KERNEL) || defined(_WANT_FILE)
+#include <sys/lock.h>
+#include <sys/mutex.h>
+#include <sys/queue.h>
+#include <sys/rangelock.h>
 #include <vm/vm.h>
 
 struct file;
@@ -215,6 +219,9 @@ struct shmfd {
 
 	struct label	*shm_label;		/* MAC label */
 	const char	*shm_path;
+
+	struct rangelock shm_rl;
+	struct mtx	shm_mtx;
 };
 #endif