vbox: Make CreateHardDisk support all vbox versions

The CreateHardDiskMedium only support create HardDisk for medium
type, and it only works when vbox version >= 3.1. This patch make
the function workable with all vbox versions and rename it as
CreateHardDisk.

In vbox 2.2 and 3.0 this function will create a IHardDisk object.
In vbox later than 3.0, this function will create a IMedium object.

src/vbox/vbox_common.c

@@ -5115,7 +5115,7 @@ vboxSnapshotRedefine(virDomainPtr dom,
             if (virAsprintf(&newLocationUtf8, "%sfakedisk-%d.vdi", machineLocationPath, it) < 0)
                 goto cleanup;
             VBOX_UTF8_TO_UTF16(newLocationUtf8, &newLocation);
-            rc = gVBoxAPI.UIVirtualBox.CreateHardDiskMedium(data->vboxObj,
+            rc = gVBoxAPI.UIVirtualBox.CreateHardDisk(data->vboxObj,
                                                       formatUtf16,
                                                       newLocation,
                                                       &newMedium);
@@ -6877,7 +6877,7 @@ vboxDomainSnapshotDeleteMetadataOnly(virDomainSnapshotPtr snapshot)
                                 machineLocationPath, def->parent, it) < 0)
                     goto cleanup;
                 VBOX_UTF8_TO_UTF16(newLocationUtf8, &newLocation);
-                rc = gVBoxAPI.UIVirtualBox.CreateHardDiskMedium(data->vboxObj,
+                rc = gVBoxAPI.UIVirtualBox.CreateHardDisk(data->vboxObj,
                                                           formatUtf16,
                                                           newLocation,
                                                           &newMedium);

src/vbox/vbox_tmpl.c

@@ -3456,17 +3456,13 @@ _virtualboxCreateMachine(vboxGlobalData *data, virDomainDefPtr def, IMachine **m
 }
 
 static nsresult
-_virtualboxCreateHardDiskMedium(IVirtualBox *vboxObj ATTRIBUTE_UNUSED,
-                                PRUnichar *format ATTRIBUTE_UNUSED,
-                                PRUnichar *location ATTRIBUTE_UNUSED,
-                                IMedium **medium ATTRIBUTE_UNUSED)
+_virtualboxCreateHardDisk(IVirtualBox *vboxObj, PRUnichar *format,
+                          PRUnichar *location, IHardDisk **hardDisk)
 {
-#if VBOX_API_VERSION < 3001000
-    vboxUnsupported();
-    return 0;
-#else /* VBOX_API_VERSION >= 3001000 */
-    return vboxObj->vtbl->CreateHardDisk(vboxObj, format, location, medium);
-#endif /* VBOX_API_VERSION >= 3001000 */
+    /* In vbox 2.2 and 3.0, this function will create a IHardDisk object.
+     * In vbox 3.1 and later, this function will create a IMedium object.
+     */
+    return vboxObj->vtbl->CreateHardDisk(vboxObj, format, location, hardDisk);
 }
 
 static nsresult
@@ -5209,7 +5205,7 @@ static vboxUniformedIVirtualBox _UIVirtualBox = {
     .GetSystemProperties = _virtualboxGetSystemProperties,
     .GetHost = _virtualboxGetHost,
     .CreateMachine = _virtualboxCreateMachine,
-    .CreateHardDiskMedium = _virtualboxCreateHardDiskMedium,
+    .CreateHardDisk = _virtualboxCreateHardDisk,
     .RegisterMachine = _virtualboxRegisterMachine,
     .FindHardDisk = _virtualboxFindHardDisk,
     .OpenMedium = _virtualboxOpenMedium,

src/vbox/vbox_uniformed_api.h

@@ -194,7 +194,7 @@ typedef struct {
     nsresult (*GetSystemProperties)(IVirtualBox *vboxObj, ISystemProperties **systemProperties);
     nsresult (*GetHost)(IVirtualBox *vboxObj, IHost **host);
     nsresult (*CreateMachine)(vboxGlobalData *data, virDomainDefPtr def, IMachine **machine, char *uuidstr);
-    nsresult (*CreateHardDiskMedium)(IVirtualBox *vboxObj, PRUnichar *format, PRUnichar *location, IMedium **medium);
+    nsresult (*CreateHardDisk)(IVirtualBox *vboxObj, PRUnichar *format, PRUnichar *location, IHardDisk **hardDisk);
     nsresult (*RegisterMachine)(IVirtualBox *vboxObj, IMachine *machine);
     nsresult (*FindHardDisk)(IVirtualBox *vboxObj, PRUnichar *location, PRUint32 deviceType,
                              PRUint32 accessMode, IHardDisk **hardDisk);