From 14dc44913037f6e2ba9a2871addd3d4a49498797 Mon Sep 17 00:00:00 2001
From: Steven Smith <ssmith@xensource.com>
Date: Fri, 1 Dec 2006 12:03:15 +0000
Subject: [PATCH] [PVFB] Make sure that framebuffer backend goes away when the
 domain terminates, and that it cleans up its area of xenstore.

Tidy up argument parsing a little while I'm here.

Signed-off-by: Steven Smith <sos22@cam.ac.uk>
---
 tools/xenfb/sdlfb.c | 10 +++++++++-
 tools/xenfb/vncfb.c | 10 +++++++++-
 tools/xenfb/xenfb.c | 27 ++++++++++++++++++++++++---
 tools/xenfb/xenfb.h |  1 +
 4 files changed, 43 insertions(+), 5 deletions(-)

diff --git a/tools/xenfb/sdlfb.c b/tools/xenfb/sdlfb.c
index cc5f8d6f52..6276c34659 100644
--- a/tools/xenfb/sdlfb.c
+++ b/tools/xenfb/sdlfb.c
@@ -204,6 +204,7 @@ static int sdl_on_event(struct xenfb *xenfb, SDL_Event *event)
 static struct option options[] = {
 	{ "domid", 1, NULL, 'd' },
 	{ "title", 1, NULL, 't' },
+	{ NULL }
 };
 
 int main(int argc, char **argv)
@@ -220,6 +221,7 @@ int main(int argc, char **argv)
 	int do_quit = 0;
 	int opt;
 	char *endp;
+	int retval;
 
 	while ((opt = getopt_long(argc, argv, "d:t:", options,
 				  NULL)) != -1) {
@@ -234,6 +236,8 @@ int main(int argc, char **argv)
                 case 't':
 			title = strdup(optarg);
 			break;
+		case '?':
+			exit(1);
                 }
         }
         if (optind != argc) {
@@ -323,7 +327,11 @@ int main(int argc, char **argv)
                 if (do_quit)
 			break;
 
-		xenfb_poll(xenfb, &readfds);
+		retval = xenfb_poll(xenfb, &readfds);
+		if (retval == -2)
+		    xenfb_teardown(xenfb);
+		if (retval < 0)
+		    break;
 	}
 
 	xenfb_delete(xenfb);
diff --git a/tools/xenfb/vncfb.c b/tools/xenfb/vncfb.c
index 2fc970e0cc..49fc730625 100644
--- a/tools/xenfb/vncfb.c
+++ b/tools/xenfb/vncfb.c
@@ -253,6 +253,7 @@ static struct option options[] = {
 	{ "title", 1, NULL, 't' },
 	{ "unused", 0, NULL, 'u' },
 	{ "listen", 1, NULL, 'l' },
+	{ NULL }
 };
 
 int main(int argc, char **argv)
@@ -272,6 +273,7 @@ int main(int argc, char **argv)
 	int nfds;
 	char portstr[10];
 	char *endp;
+	int r;
 
 	while ((opt = getopt_long(argc, argv, "d:p:t:u", options,
 				  NULL)) != -1) {
@@ -301,6 +303,8 @@ int main(int argc, char **argv)
                 case 'l':
 			listen = strdup(optarg);
 			break;
+		case '?':
+			exit(1);
                 }
         }
         if (optind != argc) {
@@ -383,7 +387,11 @@ int main(int argc, char **argv)
 			break;
 		}
 
-		xenfb_poll(xenfb, &readfds);
+		r = xenfb_poll(xenfb, &readfds);
+		if (r == -2)
+		    xenfb_teardown(xenfb);
+		if (r < 0)
+		    break;
 	}
 
 	rfbScreenCleanup(server);
diff --git a/tools/xenfb/xenfb.c b/tools/xenfb/xenfb.c
index 82d31772df..496a365079 100644
--- a/tools/xenfb/xenfb.c
+++ b/tools/xenfb/xenfb.c
@@ -187,6 +187,17 @@ struct xenfb *xenfb_new(void)
 	return NULL;
 }
 
+/* Remove the backend area in xenbus since the framebuffer really is
+   going away. */
+void xenfb_teardown(struct xenfb *xenfb_pub)
+{
+       struct xenfb_private *xenfb = (struct xenfb_private *)xenfb_pub;
+
+       xs_rm(xenfb->xsh, XBT_NULL, xenfb->fb.nodename);
+       xs_rm(xenfb->xsh, XBT_NULL, xenfb->kbd.nodename);
+}
+
+
 void xenfb_delete(struct xenfb *xenfb_pub)
 {
 	struct xenfb_private *xenfb = (struct xenfb_private *)xenfb_pub;
@@ -564,7 +575,7 @@ static void xenfb_on_kbd_event(struct xenfb_private *xenfb)
 	xc_evtchn_notify(xenfb->evt_xch, xenfb->kbd.port);
 }
 
-static void xenfb_on_state_change(struct xenfb_device *dev)
+static int xenfb_on_state_change(struct xenfb_device *dev)
 {
 	enum xenbus_state state;
 
@@ -572,6 +583,10 @@ static void xenfb_on_state_change(struct xenfb_device *dev)
 
 	switch (state) {
 	case XenbusStateUnknown:
+		/* There was an error reading the frontend state.  The
+		   domain has probably gone away; in any case, there's
+		   not much point in us continuing. */
+		return -1;
 	case XenbusStateInitialising:
 	case XenbusStateInitWait:
 	case XenbusStateInitialised:
@@ -585,14 +600,17 @@ static void xenfb_on_state_change(struct xenfb_device *dev)
 		xs_unwatch(dev->xenfb->xsh, dev->otherend, "");
 		xenfb_switch_state(dev, state);
 	}
+	return 0;
 }
 
+/* Returns 0 normally, -1 on error, or -2 if the domain went away. */
 int xenfb_poll(struct xenfb *xenfb_pub, fd_set *readfds)
 {
 	struct xenfb_private *xenfb = (struct xenfb_private *)xenfb_pub;
 	evtchn_port_t port;
 	unsigned dummy;
 	char **vec;
+	int r;
 
 	if (FD_ISSET(xc_evtchn_fd(xenfb->evt_xch), readfds)) {
 		port = xc_evtchn_pending(xenfb->evt_xch);
@@ -611,8 +629,11 @@ int xenfb_poll(struct xenfb *xenfb_pub, fd_set *readfds)
 	if (FD_ISSET(xs_fileno(xenfb->xsh), readfds)) {
 		vec = xs_read_watch(xenfb->xsh, &dummy);
 		free(vec);
-		xenfb_on_state_change(&xenfb->fb);
-		xenfb_on_state_change(&xenfb->kbd);
+		r = xenfb_on_state_change(&xenfb->fb);
+		if (r == 0)
+			r = xenfb_on_state_change(&xenfb->kbd);
+		if (r == -1)
+			return -2;
 	}
 
 	return 0;
diff --git a/tools/xenfb/xenfb.h b/tools/xenfb/xenfb.h
index 007eb3b9b4..c08d979b39 100644
--- a/tools/xenfb/xenfb.h
+++ b/tools/xenfb/xenfb.h
@@ -21,6 +21,7 @@ struct xenfb
 
 struct xenfb *xenfb_new(void);
 void xenfb_delete(struct xenfb *xenfb);
+void xenfb_teardown(struct xenfb *xenfb);
 
 int xenfb_attach_dom(struct xenfb *xenfb, int domid);
 
-- 
2.30.2