[libvirt] [PATCH] tests: Don't touch /dev/vhost-net in qemuxml2argvtest

[Martin Kletzander]

The code is trying to open /dev/vhost-net from the host machine and if the
current user has access to it, the command line will end up having two more
options for an interface (,vhost=on,vhostfd=X where X is next free file
descriptor).

Signed-off-by: Martin Kletzander <mkletzan at redhat.com>
---
 tests/qemuxml2argvmock.c | 36 ++++++++++++++++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/tests/qemuxml2argvmock.c b/tests/qemuxml2argvmock.c
index 177b24e0a953..11626e2794c1 100644
--- a/tests/qemuxml2argvmock.c
+++ b/tests/qemuxml2argvmock.c
@@ -20,6 +20,10 @@
 
 #include <config.h>
 
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
 #include "internal.h"
 #include "viralloc.h"
 #include "vircommand.h"
@@ -188,3 +192,35 @@ virNetDevOpenvswitchGetVhostuserIfname(const char *path ATTRIBUTE_UNUSED,
 {
     return VIR_STRDUP(*ifname, "vhost-user0");
 }
+
+static int (*real_open)(const char *path, int flags, ...);
+
+static void init_syms(void)
+{
+    if (real_open)
+        return;
+
+    VIR_MOCK_REAL_INIT(open);
+}
+
+int open(const char *path, int flags, ...)
+{
+    va_list ap;
+    mode_t mode = 0;
+
+    init_syms();
+
+    if (STREQ(path, "/dev/vhost-net"))
+        return -1;
+
+    /* The mode argument is mandatory when O_CREAT is set in flags,
+     * otherwise the argument is ignored.
+     */
+    if (flags & O_CREAT) {
+        va_start(ap, flags);
+        mode = (mode_t) va_arg(ap, int);
+        va_end(ap);
+    }
+
+    return real_open(path, flags, mode);
+}
-- 
2.17.0