qdev: Fix exit code for -device ?

Help was shoehorned into device creation, qdev_device_add().  Since
help doesn't create a device, it returns NULL, which looks to callers
just like failed device creation.  Monitor handler do_device_add()
doesn't care, but main() exits unsuccessfully.

Move help out of device creation, into new qdev_device_help().

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/vl.c b/vl.c
index 6f1e1ab71f..39833fc3b3 100644
--- a/vl.c
+++ b/vl.c
@@ -4459,6 +4459,11 @@ char *qemu_find_file(int type, const char *name)
     return buf;
 }
 
+static int device_help_func(QemuOpts *opts, void *opaque)
+{
+    return qdev_device_help(opts);
+}
+
 static int device_init_func(QemuOpts *opts, void *opaque)
 {
     DeviceState *dev;
@@ -5828,6 +5833,9 @@ int main(int argc, char **argv, char **envp)
 
     module_call_init(MODULE_INIT_DEVICE);
 
+    if (qemu_opts_foreach(&qemu_device_opts, device_help_func, NULL, 0) != 0)
+        exit(0);
+
     if (watchdog) {
         i = select_watchdog(watchdog);
         if (i > 0)