tests: Add parameter to qtest_init_without_qmp_handshake

Allow callers to choose whether to allow OOB support during a test;
for now, all existing callers pass false, but the next patch will
add a new caller.  Also, rewrite the monitor setup to be generic
(using the -qmp shorthand is insufficient for honoring the parameter).

Based on an idea by Peter Xu, in <20180326063901.27425-8-peterx@redhat.com>
Signed-off-by: NEric Blake <eblake@redhat.com>
Message-Id: <20180327013620.1644387-4-eblake@redhat.com>
Tested-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Acked-by: NPeter Xu <peterx@redhat.com>
Reviewed-by: NMarc-André Lureau <marcandre.lureau@redhat.com>

tests/libqtest.c

@@ -166,7 +166,8 @@ static const char *qtest_qemu_binary(void)
     return qemu_bin;
 }
 
-QTestState *qtest_init_without_qmp_handshake(const char *extra_args)
+QTestState *qtest_init_without_qmp_handshake(bool use_oob,
+                                             const char *extra_args)
 {
     QTestState *s;
     int sock, qmpsock, i;
@@ -199,12 +200,13 @@ QTestState *qtest_init_without_qmp_handshake(const char *extra_args)
         command = g_strdup_printf("exec %s "
                                   "-qtest unix:%s,nowait "
                                   "-qtest-log %s "
-                                  "-qmp unix:%s,nowait "
+                                  "-chardev socket,path=%s,nowait,id=char0 "
+                                  "-mon chardev=char0,mode=control%s "
                                   "-machine accel=qtest "
                                   "-display none "
                                   "%s", qemu_binary, socket_path,
                                   getenv("QTEST_LOG") ? "/dev/fd/2" : "/dev/null",
-                                  qmp_socket_path,
+                                  qmp_socket_path, use_oob ? ",x-oob=on" : "",
                                   extra_args ?: "");
         execlp("/bin/sh", "sh", "-c", command, NULL);
         exit(1);
@@ -239,7 +241,7 @@ QTestState *qtest_init_without_qmp_handshake(const char *extra_args)
 
 QTestState *qtest_init(const char *extra_args)
 {
-    QTestState *s = qtest_init_without_qmp_handshake(extra_args);
+    QTestState *s = qtest_init_without_qmp_handshake(false, extra_args);
 
     /* Read the QMP greeting and then do the handshake */
     qtest_qmp_discard_response(s, "");

tests/libqtest.h

@@ -56,11 +56,14 @@ QTestState *qtest_init(const char *extra_args);
 
 /**
  * qtest_init_without_qmp_handshake:
- * @extra_args: other arguments to pass to QEMU.
+ * @use_oob: true to have the server advertise OOB support
+ * @extra_args: other arguments to pass to QEMU.  CAUTION: these
+ * arguments are subject to word splitting and shell evaluation.
  *
  * Returns: #QTestState instance.
  */
-QTestState *qtest_init_without_qmp_handshake(const char *extra_args);
+QTestState *qtest_init_without_qmp_handshake(bool use_oob,
+                                             const char *extra_args);
 
 /**
  * qtest_quit:

tests/qmp-test.c

@@ -81,7 +81,7 @@ static void test_qmp_protocol(void)
     QList *capabilities;
     QTestState *qts;
 
-    qts = qtest_init_without_qmp_handshake(common_args);
+    qts = qtest_init_without_qmp_handshake(false, common_args);
 
     /* Test greeting */
     resp = qtest_qmp_receive(qts);