Replace select backends with poll backends. selscan() and pollscan()

now call the poll backend.  With this change we implement greater
poll(2) functionality instead of emulating it via the select backend.
Adapted from NetBSD and including some changes from FreeBSD.
Tested by many, deraadt@ OK

1 files changed, 16 insertions, 14 deletions

diff --git a/sys/dev/systrace.c b/sys/dev/systrace.c
index d7c8972207d..0dfbbe5ff44 100644
--- a/sys/dev/systrace.c
+++ b/sys/dev/systrace.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: systrace.c,v 1.31 2003/08/15 20:32:16 tedu Exp $	*/
+/*	$OpenBSD: systrace.c,v 1.32 2003/09/23 16:51:12 millert Exp $	*/
 /*
  * Copyright 2002 Niels Provos <provos@citi.umich.edu>
  * All rights reserved.
@@ -45,6 +45,7 @@
 #include <sys/lock.h>
 #include <sys/pool.h>
 #include <sys/mount.h>
+#include <sys/poll.h>
 
 #include <compat/common/compat_util.h>
 
@@ -59,14 +60,14 @@ int	systraceclose(dev_t, int, int, struct proc *);
 int	systraceread(dev_t, struct uio *, int);
 int	systracewrite(dev_t, struct uio *, int);
 int	systraceioctl(dev_t, u_long, caddr_t, int, struct proc *);
-int	systraceselect(dev_t, int, struct proc *);
+int	systracepoll(dev_t, int, struct proc *);
 
 uid_t	systrace_seteuid(struct proc *,  uid_t);
 gid_t	systrace_setegid(struct proc *,  gid_t);
 int	systracef_read(struct file *, off_t *, struct uio *, struct ucred *);
 int	systracef_write(struct file *, off_t *, struct uio *, struct ucred *);
 int	systracef_ioctl(struct file *, u_long, caddr_t, struct proc *p);
-int	systracef_select(struct file *, int, struct proc *);
+int	systracef_poll(struct file *, int, struct proc *);
 int	systracef_kqfilter(struct file *, struct knote *);
 int	systracef_stat(struct file *, struct stat *, struct proc *);
 int	systracef_close(struct file *, struct proc *);
@@ -152,7 +153,7 @@ static struct fileops systracefops = {
 	systracef_read,
 	systracef_write,
 	systracef_ioctl,
-	systracef_select,
+	systracef_poll,
 	systracef_kqfilter,
 	systracef_stat,
 	systracef_close
@@ -361,26 +362,27 @@ systracef_ioctl(fp, cmd, data, p)
 
 /* ARGSUSED */
 int
-systracef_select(fp, which, p)
+systracef_poll(fp, events, p)
 	struct file *fp;
-	int which;
+	int events;
 	struct proc *p;
 {
 	struct fsystrace *fst = (struct fsystrace *)fp->f_data;
-	int ready = 0;
+	int revents = 0;
 
-	if (which != FREAD)
+	if ((events & (POLLIN | POLLRDNORM)) == 0)
 		return (0);
 
 	systrace_lock();
 	lockmgr(&fst->lock, LK_EXCLUSIVE, NULL, p);
 	systrace_unlock();
-	ready = TAILQ_FIRST(&fst->messages) != NULL;
-	if (!ready)
+	if (!TAILQ_EMPTY(&fst->messages))
+		revents = events & (POLLIN | POLLRDNORM);
+	else
 		selrecord(p, &fst->si);
 	lockmgr(&fst->lock, LK_RELEASE, NULL, p);
 
-	return (ready);
+	return (revents);
 }
 
 /* ARGSUSED */
@@ -558,12 +560,12 @@ systraceioctl(dev, cmd, data, flag, p)
 }
 
 int
-systraceselect(dev, rw, p)
+systracepoll(dev, events, p)
 	dev_t	dev;
-	int	rw;
+	int	events;
 	struct proc *p;
 {
-	return (0);
+	return (seltrue(dev, events, p));
 }
 
 void