vl: New qemu_get_machine_opts()

To be used in the next few commits to fix or clean up queries of
"machine" options (-machine and its sugared forms).
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Message-id: 1372943363-24081-4-git-send-email-armbru@redhat.com
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

include/sysemu/sysemu.h

@@ -185,6 +185,8 @@ char *get_boot_devices_list(size_t *size);
 
 DeviceState *get_boot_device(uint32_t position);
 
+QemuOpts *qemu_get_machine_opts(void);
+
 bool usb_enabled(bool default_usb);
 
 extern QemuOptsList qemu_drive_opts;

vl.c

@@ -516,6 +516,25 @@ static QemuOptsList qemu_realtime_opts = {
     },
 };
 
+/**
+ * Get machine options
+ *
+ * Returns: machine options (never null).
+ */
+QemuOpts *qemu_get_machine_opts(void)
+{
+    QemuOptsList *list;
+    QemuOpts *opts;
+
+    list = qemu_find_opts("machine");
+    assert(list);
+    opts = qemu_opts_find(list, NULL);
+    if (!opts) {
+        opts = qemu_opts_create_nofail(list);
+    }
+    return opts;
+}
+
 const char *qemu_get_vm_name(void)
 {
     return qemu_name;