xend: Fix Py_BuildValue() invocation (don't use I specifier).

Various error-handlign cleanup and fix a reference leakage.
Signed-off-by: Keir Fraser <keir@xensource.com>

tools/python/xen/lowlevel/xc/xc.c

@@ -50,17 +50,21 @@ static PyObject *pyxc_error_to_exception(void)
     const xc_error *err = xc_get_last_error();
     const char *desc = xc_error_code_to_desc(err->code);
 
-    if (err->code == XC_ERROR_NONE)
+    if ( err->code == XC_ERROR_NONE )
         return PyErr_SetFromErrno(xc_error_obj);
 
-    if (err->message[0] != '\0')
+    if ( err->message[0] != '\0' )
 	pyerr = Py_BuildValue("(iss)", err->code, desc, err->message);
     else
 	pyerr = Py_BuildValue("(is)", err->code, desc);
 
     xc_clear_last_error();
 
-    PyErr_SetObject(xc_error_obj, pyerr);
+    if ( pyerr != NULL )
+    {
+        PyErr_SetObject(xc_error_obj, pyerr);
+        Py_DECREF(pyerr);
+    }
 
     return NULL;
 }
@@ -70,13 +74,13 @@ static PyObject *pyxc_domain_dumpcore(XcObject *self, PyObject *args)
     uint32_t dom;
     char *corefile;
 
-    if (!PyArg_ParseTuple(args, "is", &dom, &corefile))
+    if ( !PyArg_ParseTuple(args, "is", &dom, &corefile) )
         return NULL;
 
     if ( (corefile == NULL) || (corefile[0] == '\0') )
         return NULL;
 
-    if (xc_domain_dumpcore(self->xc_handle, dom, corefile) != 0)
+    if ( xc_domain_dumpcore(self->xc_handle, dom, corefile) != 0 )
         return pyxc_error_to_exception();
     
     Py_INCREF(zero);
@@ -168,10 +172,10 @@ static PyObject *pyxc_domain_shutdown(XcObject *self, PyObject *args)
 {
     uint32_t dom, reason;
 
-    if (!PyArg_ParseTuple(args, "ii", &dom, &reason))
+    if ( !PyArg_ParseTuple(args, "ii", &dom, &reason) )
       return NULL;
 
-    if (xc_domain_shutdown(self->xc_handle, dom, reason) != 0)
+    if ( xc_domain_shutdown(self->xc_handle, dom, reason) != 0 )
         return pyxc_error_to_exception();
     
     Py_INCREF(zero);
@@ -183,10 +187,10 @@ static PyObject *pyxc_domain_resume(XcObject *self, PyObject *args)
     uint32_t dom;
     int fast;
 
-    if (!PyArg_ParseTuple(args, "ii", &dom, &fast))
+    if ( !PyArg_ParseTuple(args, "ii", &dom, &fast) )
         return NULL;
 
-    if (xc_domain_resume(self->xc_handle, dom, fast) != 0)
+    if ( xc_domain_resume(self->xc_handle, dom, fast) != 0 )
         return pyxc_error_to_exception();
 
     Py_INCREF(zero);
@@ -282,7 +286,7 @@ static PyObject *pyxc_domain_getinfo(XcObject *self,
                                      PyObject *args,
                                      PyObject *kwds)
 {
-    PyObject *list, *info_dict;
+    PyObject *list, *info_dict, *pyhandle;
 
     uint32_t first_dom = 0;
     int max_doms = 1024, nr_doms, i, j;
@@ -308,12 +312,9 @@ static PyObject *pyxc_domain_getinfo(XcObject *self,
     list = PyList_New(nr_doms);
     for ( i = 0 ; i < nr_doms; i++ )
     {
-        PyObject *pyhandle = PyList_New(sizeof(xen_domain_handle_t));
-        for ( j = 0; j < sizeof(xen_domain_handle_t); j++ )
-            PyList_SetItem(pyhandle, j, PyInt_FromLong(info[i].handle[j]));
         info_dict = Py_BuildValue(
-            "{s:i,s:I,s:I,s:i,s:i,s:i,s:i,s:i,s:i,s:i"
-            ",s:k,s:L,s:k,s:i,s:I}",
+            "{s:i,s:i,s:i,s:i,s:i,s:i,s:i,s:i,s:i,s:i"
+            ",s:k,s:L,s:k,s:i,s:i}",
             "domid",           (int)info[i].domid,
             "online_vcpus",    info[i].nr_online_vcpus,
             "max_vcpu_id",     info[i].max_vcpu_id,
@@ -324,12 +325,21 @@ static PyObject *pyxc_domain_getinfo(XcObject *self,
             "paused",          info[i].paused,
             "blocked",         info[i].blocked,
             "running",         info[i].running,
-            
             "mem_kb",          info[i].nr_pages*(XC_PAGE_SIZE/1024),
             "cpu_time",        (long long)info[i].cpu_time,
             "maxmem_kb",       info[i].max_memkb,
             "ssidref",         (int)info[i].ssidref,
             "shutdown_reason", info[i].shutdown_reason);
+        pyhandle = PyList_New(sizeof(xen_domain_handle_t));
+        if ( (pyhandle == NULL) || (info_dict == NULL) )
+        {
+            Py_DECREF(list);
+            if ( pyhandle  != NULL ) { Py_DECREF(pyhandle);  }
+            if ( info_dict != NULL ) { Py_DECREF(info_dict); }
+            return NULL;
+        }
+        for ( j = 0; j < sizeof(xen_domain_handle_t); j++ )
+            PyList_SetItem(pyhandle, j, PyInt_FromLong(info[i].handle[j]));
         PyDict_SetItemString(info_dict, "handle", pyhandle);
         Py_DECREF(pyhandle);
         PyList_SetItem(list, i, info_dict);