introduce a filter called EVFILT_DEVICE that can be used to notify

listeners of device state changes.
currently only supports NOTE_CHANGE that will be used by drm(4)

ok kettenis@

diff --git a/lib/libc/sys/kqueue.2 b/lib/libc/sys/kqueue.2
index 7dbd3a5..41fbc23 100644 (file)
--- a/lib/libc/sys/kqueue.2
+++ b/lib/libc/sys/kqueue.2
@@ -1,4 +1,4 @@
-.\"    $OpenBSD: kqueue.2,v 1.35 2017/07/10 06:38:07 dlg Exp $
+.\"    $OpenBSD: kqueue.2,v 1.36 2018/01/13 12:58:40 robert Exp $
 .\"
 .\" Copyright (c) 2000 Jonathan Lemon
 .\" All rights reserved.
@@ -26,7 +26,7 @@
 .\"
 .\" $FreeBSD: src/lib/libc/sys/kqueue.2,v 1.18 2001/02/14 08:48:35 guido Exp $
 .\"
-.Dd $Mdocdate: July 10 2017 $
+.Dd $Mdocdate: January 13 2018 $
 .Dt KQUEUE 2
 .Os
 .Sh NAME
@@ -451,6 +451,19 @@ contains the number of times the timeout has expired since the last call to
 This filter automatically sets the
 .Dv EV_CLEAR
 flag internally.
+.It Dv EVFILT_DEVICE
+Takes a descriptor as the identifier, and the events to watch for in 
+.Va fflags ,
+and returns when one or more of the reuqested events occur on the
+descriptor. The events to monitor are:
+.Bl -tag -width XXNOTE_CHANGE
+.It Dv NOTE_CHANGE
+A device change event has occured, e.g. an HDMI cable has been plugged in to a port.
+.El
+.Pp
+On return,
+.Va fflags
+contains the events which triggered the filter.
 .El
 .Sh RETURN VALUES
 .Fn kqueue

diff --git a/sys/kern/kern_event.c b/sys/kern/kern_event.c
index 9666320..fb9cad3 100644 (file)
--- a/sys/kern/kern_event.c
+++ b/sys/kern/kern_event.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: kern_event.c,v 1.83 2017/12/18 10:10:53 mpi Exp $     */
+/*     $OpenBSD: kern_event.c,v 1.84 2018/01/13 12:58:40 robert Exp $  */
 
 /*-
  * Copyright (c) 1999,2000,2001 Jonathan Lemon <jlemon@FreeBSD.org>
@@ -137,6 +137,7 @@ struct filterops *sysfilt_ops[] = {
        &proc_filtops,                  /* EVFILT_PROC */
        &sig_filtops,                   /* EVFILT_SIGNAL */
        &timer_filtops,                 /* EVFILT_TIMER */
+       &file_filtops,                  /* EVFILT_DEVICE */
 };
 
 void KQREF(struct kqueue *);

diff --git a/sys/sys/event.h b/sys/sys/event.h
index c3b2b28..e29c112 100644 (file)
--- a/sys/sys/event.h
+++ b/sys/sys/event.h
@@ -1,4 +1,4 @@
-/*     $OpenBSD: event.h,v 1.29 2017/12/21 21:04:38 millert Exp $      */
+/*     $OpenBSD: event.h,v 1.30 2018/01/13 12:58:40 robert Exp $       */
 
 /*-
  * Copyright (c) 1999,2000,2001 Jonathan Lemon <jlemon@FreeBSD.org>
@@ -38,8 +38,9 @@
 #define EVFILT_PROC            (-5)    /* attached to struct process */
 #define EVFILT_SIGNAL          (-6)    /* attached to struct process */
 #define EVFILT_TIMER           (-7)    /* timers */
+#define EVFILT_DEVICE          (-8)    /* devices */
 
-#define EVFILT_SYSCOUNT                7
+#define EVFILT_SYSCOUNT                8
 
 #define EV_SET(kevp_, a, b, c, d, e, f) do {   \
        struct kevent *kevp = (kevp_);          \
@@ -111,6 +112,9 @@ struct kevent {
 #define        NOTE_TRACKERR   0x00000002              /* could not track child */
 #define        NOTE_CHILD      0x00000004              /* am a child process */
 
+/* data/hint flags for EVFILT_DEVICE, shared with userspace */
+#define NOTE_CHANGE    0x00000001              /* device change event */
+
 /*
  * This is currently visible to userland to work around broken
  * programs which pull in <sys/proc.h> or <sys/selinfo.h>.