tests: Introduce generic device hot-plug/hot-unplug functions

A lot of tests provide code for adding and removing a device via the
device_add and device_del QMP commands. Maintaining this code in so many
places is cumbersome and error-prone (some of the code parts check the
responses for device deletion in an incorrect way, for example, we've got
to deal with both, error code and DEVICE_DEL event here). So let's provide
some proper generic functions for adding and removing a device instead.

The code for correctly unplugging a device has been taken from a patch
from Peter Xu.

Reviewed-by: Peter Xu <peterx@redhat.com>
Tested-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>

1 files changed, 19 insertions, 0 deletions

diff --git a/tests/libqtest.h b/tests/libqtest.h
index 3ae570927a..44803d772e 100644
--- a/tests/libqtest.h
+++ b/tests/libqtest.h
@@ -927,4 +927,23 @@ QDict *qmp_fd(int fd, const char *fmt, ...);
  */
 void qtest_cb_for_every_machine(void (*cb)(const char *machine));
 
+/**
+ * qtest_qmp_device_add:
+ * @driver: Name of the device that should be added
+ * @id: Identification string
+ * @fmt: printf-like format string for further options to device_add
+ *
+ * Generic hot-plugging test via the device_add QMP command.
+ */
+void qtest_qmp_device_add(const char *driver, const char *id, const char *fmt,
+                          ...) GCC_FMT_ATTR(3, 4);
+
+/**
+ * qtest_qmp_device_del:
+ * @id: Identification string
+ *
+ * Generic hot-unplugging test via the device_del QMP command.
+ */
+void qtest_qmp_device_del(const char *id);
+
 #endif