update from main archive 960105 cvs/libc-970107 cvs/libc-970106

1 files changed, 57 insertions, 0 deletions

diff --git a/sysdeps/i386/selectbits.h b/sysdeps/i386/selectbits.h
new file mode 100644
index 0000000000..973ecad58e
--- /dev/null
+++ b/sysdeps/i386/selectbits.h
@@ -0,0 +1,57 @@
+/* Copyright (C) 1997 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#ifndef _SELECTBITS_H
+#define _SELECTBITS_H	1
+
+#if defined __GNUC__ && __GNUC__ >= 2
+
+#define __FD_ZERO(fdsetp) \
+  __asm__ __volatile__ ("cld ; rep ; stosl"				      \
+			: "=m" (*(__fd_set *) (fdsetp))			      \
+			: "a" (0), "c" (sizeof (__fd_set)		      \
+					/ sizeof (__fd_mask)),		      \
+			  "D" ((__fd_set *) (fdsetp))			      \
+			:"cx","di")
+#define __FD_SET(fd, fdsetp) \
+  __asm__ __volatile__ ("btsl %1,%0"					      \
+			: "=m" (*(__fd_set *) (fdsetp))			      \
+			: "r" ((int) (fd)))
+#define __FD_CLR(fd, fdsetp) \
+  __asm__ __volatile__ ("btrl %1,%0"					      \
+			: "=m" (*(__fd_set *) (fdsetp))			      \
+			: "r" ((int) (fd)))
+#define __FD_ISSET(fd, fdsetp) \
+  (__extension__							      \
+   ({unsigned char __result;						      \
+     __asm__ __volatile__ ("btl %1,%2 ; setb %0"			      \
+			   : "=q" (__result)				      \
+			   : "r" ((int) (fd)), "m" (*(__fd_set *) (fdsetp))); \
+     __result; }))
+
+#else	/* ! GNU CC */
+
+#define __FD_ZERO(set)  \
+  ((void) memset ((__ptr_t) (set), 0, sizeof (fd_set)))
+#define __FD_SET(d, set)	((set)->fds_bits[__FDELT(d)] |= __FDMASK(d))
+#define __FD_CLR(d, set)	((set)->fds_bits[__FDELT(d)] &= ~__FDMASK(d))
+#define __FD_ISSET(d, set)	((set)->fds_bits[__FDELT(d)] & __FDMASK(d))
+
+#endif	/* GNU CC */
+
+#endif /* selectbits.h */