tests: Clean up string interpolation around qtest_qmp_device_add()

Leaving interpolation into JSON to qmp() is more robust than building
QMP input manually, as explained in the commit before previous.

qtest_qmp_device_add() and its wrappers interpolate into JSON as
follows:

* qtest_qmp_device_add() interpolates members into a JSON object.

* So do its wrappers qpci_plug_device_test() and usb_test_hotplug().

* usb_test_hotplug() additionally interpolates strings and numbers
  into JSON strings.

Clean them up:

* Have qtest_qmp_device_add() take its extra device properties as
  arguments for qdict_from_jsonf_nofail() instead of a string
  containing JSON members.

* Drop qpci_plug_device_test(), use qtest_qmp_device_add()
  directly.

* Change usb_test_hotplug() parameter @port to string, to avoid
  interpolation.  Interpolate @hcd_id separately.

Bonus: gets rid of a non-literal format string.  A step towards
compile-time format string checking without triggering
-Wformat-nonliteral.

Cc: Thomas Huth <thuth@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <20180806065344.7103-15-armbru@redhat.com>

1 files changed, 3 insertions, 5 deletions

diff --git a/tests/ivshmem-test.c b/tests/ivshmem-test.c
index 9b407a3..c37b196 100644
--- a/tests/ivshmem-test.c
+++ b/tests/ivshmem-test.c
@@ -420,19 +420,17 @@ static void test_ivshmem_server_irq(void)
 static void test_ivshmem_hotplug(void)
 {
     const char *arch = qtest_get_arch();
-    gchar *opts;
 
     qtest_start("");
 
-    opts = g_strdup_printf("'shm': '%s', 'size': '1M'", tmpshm);
-
-    qpci_plug_device_test("ivshmem", "iv1", PCI_SLOT_HP, opts);
+    qtest_qmp_device_add("ivshmem",
+                         "iv1", "{'addr': %s, 'shm': %s, 'size': '1M'}",
+                         stringify(PCI_SLOT_HP), tmpshm);
     if (strcmp(arch, "ppc64") != 0) {
         qpci_unplug_acpi_device_test("iv1", PCI_SLOT_HP);
     }
 
     qtest_end();
-    g_free(opts);
 }
 
 static void test_ivshmem_memdev(void)