auto-guest: try opening port by name before opening by id

The control channel for the tests is named 'test0', and is always the
first port of the first device we add (/dev/vport0p0).  However, the
device number can change based on pending upstream patches, so instead
of relying on the id, try opening by name first.

Signed-off-by: Amit Shah <amit.shah@redhat.com>

1 files changed, 14 insertions, 5 deletions

diff --git a/auto-virtserial-guest.c b/auto-virtserial-guest.c
index cfa90b7..53d815d 100644
--- a/auto-virtserial-guest.c
+++ b/auto-virtserial-guest.c
@@ -35,7 +35,8 @@
 #include <sys/wait.h>
 #include "virtserial.h"
 
-#define CONTROL_PORT "/dev/vport0p1"
+#define CONTROL_PORT "/dev/virtio-ports/test0"
+#define CONTROL_PORT2 "/dev/vport0p1"
 #define MAX_PORTS 10
 
 /* The fd to work with for read / write requests. Set by the open message */
@@ -604,13 +605,21 @@ int main(int argc, char *argv[])
 	install_sigio_handler();
 
 	ret = access(CONTROL_PORT, R_OK|W_OK);
-	if (ret == -1)
-		error(errno, errno, "No control port found %s", CONTROL_PORT);
+	if (ret == -1) {
+		ret = access(CONTROL_PORT2, R_OK|W_OK);
+		if (ret == -1) {
+			error(errno, errno, "No control port found %s or %s", CONTROL_PORT, CONTROL_PORT2);
+		}
+	}
 
 back_to_open:
 	cfd = open(CONTROL_PORT, O_RDWR);
-	if (cfd == -1)
-		error(errno, errno, "open control port %s", CONTROL_PORT);
+	if (cfd == -1) {
+		cfd = open(CONTROL_PORT2, O_RDWR);
+		if (cfd == -1) {
+			error(errno, errno, "open control port %s", CONTROL_PORT);
+		}
+	}
 
 	gpkt.key = KEY_STATUS_OK;
 	gpkt.value = 1;