Fix up the python bindings for snapshotting.

This involved a few fixes.  To start with,
an virDomainSnapshot object is really tied to a
domain, not a connection, so we have to generate
a slightly different object so that we can get
at self._dom for the object.

Next, we had to "dummy" up an override piece of
XML with a bogus argument that the function doesn't
actually take.  That's so that the generator places
virDomainRevertToSnapshot underneath the correct
class (namely, the virDomain class).

Finally, we had to hand-implement the
virDomainRevertToSnapshot implementation, ignoring the
bogus pointer we are being passed.

With all of this in place, I was able to successfully
take a snapshot and revert to it using only the
Python bindings.

Signed-off-by: Chris Lalancette <clalance@redhat.com>

python/generator.py

@@ -331,7 +331,7 @@ skip_impl = (
     'virNodeListDevices',
     'virNodeDeviceListCaps',
     'virConnectBaselineCPU',
-    'virDomainSnapshotListNames',
+    'virDomainRevertToSnapshot',
 )
 
 
@@ -385,6 +385,10 @@ skip_function = (
     "virStorageVolGetConnect",
 )
 
+function_skip_index_one = (
+    "virDomainRevertToSnapshot",
+)
+
 
 def print_function_wrapper(name, output, export, include):
     global py_types
@@ -688,9 +692,13 @@ classes_destructors = {
 }
 
 class_skip_connect_impl = {
-    "virConnect" : True
+    "virConnect" : True,
+    "virDomainSnapshot": True,
 }
 
+class_domain_impl = {
+    "virDomainSnapshot": True,
+}
 
 functions_noexcept = {
     'virDomainGetID': True,
@@ -986,7 +994,7 @@ def buildWrappers():
 		info = (0, func, name, ret, args, file)
 		function_classes[classe].append(info)
 	    elif name[0:3] == "vir" and len(args) >= 2 and args[1][1] == type \
-	        and file != "python_accessor":
+	        and file != "python_accessor" and not name in function_skip_index_one:
 		found = 1
 		func = nameFixup(name, classe, type, file)
 		info = (1, func, name, ret, args, file)
@@ -1128,6 +1136,8 @@ def buildWrappers():
                                   "virStorageVol", "virNodeDevice", "virSecret","virStream",
                                   "virNWFilter" ]:
                     classes.write("    def __init__(self, conn, _obj=None):\n")
+                elif classname in [ 'virDomainSnapshot' ]:
+                    classes.write("    def __init__(self, dom, _obj=None):\n")
                 else:
                     classes.write("    def __init__(self, _obj=None):\n")
 		if reference_keepers.has_key(classname):
@@ -1142,6 +1152,8 @@ def buildWrappers():
                     classes.write("        self._conn = conn\n" + \
                                   "        if not isinstance(conn, virConnect):\n" + \
                                   "            self._conn = conn._conn\n")
+                elif classname in [ "virDomainSnapshot" ]:
+                    classes.write("        self._dom = dom\n")
 		classes.write("        if _obj != None:self._o = _obj;return\n")
 		classes.write("        self._o = None\n\n");
 	    destruct=None
@@ -1158,6 +1170,10 @@ def buildWrappers():
                 classes.write("    def connect(self):\n")
                 classes.write("        return self._conn\n\n")
 
+            if class_domain_impl.has_key(classname):
+                classes.write("    def domain(self):\n")
+                classes.write("        return self._dom\n\n")
+
 	    flist = function_classes[classname]
 	    flist.sort(functionCompare)
 	    oldfile = ""
@@ -1252,6 +1268,10 @@ def buildWrappers():
                                 classes.write(
 		     "        if ret is None:raise libvirtError('%s() failed', vol=self)\n" %
                                               (name))
+                            elif classname == "virDomainSnapshot":
+                                classes.write(
+                     "        if ret is None:raise libvirtError('%s() failed', dom=self._dom)\n" %
+                                              (name))
                             else:
                                 classes.write(
 		     "        if ret is None:raise libvirtError('%s() failed')\n" %

python/libvirt-override-api.xml

@@ -277,5 +277,12 @@
       <arg name='flags' type='unsigned int' info='flags, curently unused'/>
       <return type='str *' info='the list of Names of None in case of error'/>
     </function>
+    <function name='virDomainRevertToSnapshot' file='python'>
+      <info>revert the domain to the given snapshot</info>
+      <arg name='dom' type='virDomainPtr' info='dummy domain pointer'/>
+      <arg name='snap' type='virDomainSnapshotPtr' info='pointer to the snapshot'/>
+      <arg name='flags' type='unsigned int' info='flags, curently unused'/>
+      <return type='int' info="0 on success, -1 on error"/>
+    </function>
   </symbols>
 </api>

python/libvirt-override.c

@@ -987,6 +987,28 @@ libvirt_virDomainSnapshotListNames(PyObject *self ATTRIBUTE_UNUSED,
     return(py_retval);
 }
 
+static PyObject *
+libvirt_virDomainRevertToSnapshot(PyObject *self ATTRIBUTE_UNUSED,
+                                  PyObject *args) {
+    int c_retval;
+    virDomainSnapshotPtr snap;
+    PyObject *pyobj_snap;
+    PyObject *pyobj_dom;
+    int flags;
+
+    if (!PyArg_ParseTuple(args, (char *)"OOi:virDomainRevertToSnapshot", &pyobj_dom, &pyobj_snap, &flags))
+        return(NULL);
+    snap = (virDomainSnapshotPtr) PyvirDomainSnapshot_Get(pyobj_snap);
+
+    LIBVIRT_BEGIN_ALLOW_THREADS;
+    c_retval = virDomainRevertToSnapshot(snap, flags);
+    LIBVIRT_END_ALLOW_THREADS;
+    if (c_retval < 0)
+        return VIR_PY_INT_FAIL;
+
+    return PyInt_FromLong(c_retval);
+}
+
 static PyObject *
 libvirt_virDomainGetInfo(PyObject *self ATTRIBUTE_UNUSED, PyObject *args) {
     PyObject *py_retval;
@@ -3527,6 +3549,7 @@ static PyMethodDef libvirtMethods[] = {
     {(char *) "virConnectBaselineCPU", libvirt_virConnectBaselineCPU, METH_VARARGS, NULL},
     {(char *) "virDomainGetJobInfo", libvirt_virDomainGetJobInfo, METH_VARARGS, NULL},
     {(char *) "virDomainSnapshotListNames", libvirt_virDomainSnapshotListNames, METH_VARARGS, NULL},
+    {(char *) "virDomainRevertToSnapshot", libvirt_virDomainRevertToSnapshot, METH_VARARGS, NULL},
     {NULL, NULL, 0, NULL}
 };