From: Serhiy Storchaka <storchaka@gmail.com>
Date: Sun, 6 Dec 2015 21:51:53 +0000 (+0200)
Subject: Issue25814: Propagate all errors from custom XML parser handlers
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=45cf0b7f3e3a7a4f98fb0a2a316c620d9b3f58aa;p=python

Issue25814: Propagate all errors from custom XML parser handlers
in ElementTree.iterparse().
---

diff --git a/Modules/_elementtree.c b/Modules/_elementtree.c
index 35643a785c..2bf8014f4c 100644
--- a/Modules/_elementtree.c
+++ b/Modules/_elementtree.c
@@ -1720,6 +1720,23 @@ treebuilder_dealloc(TreeBuilderObject* self)
     PyObject_Del(self);
 }
 
+LOCAL(int)
+treebuilder_append_event(TreeBuilderObject *self, PyObject *action,
+                         PyObject *node)
+{
+    if (action != NULL) {
+        PyObject *res = PyTuple_Pack(2, action, node);
+        if (res == NULL)
+            return -1;
+        if (PyList_Append(self->events, res) < 0) {
+            Py_DECREF(res);
+            return -1;
+        }
+        Py_DECREF(res);
+    }
+    return 0;
+}
+
 /* -------------------------------------------------------------------- */
 /* handlers */
 
@@ -1791,18 +1808,8 @@ treebuilder_handle_start(TreeBuilderObject* self, PyObject* tag,
     Py_INCREF(node);
     self->last = (ElementObject*) node;
 
-    if (self->start_event_obj) {
-        PyObject* res;
-        PyObject* action = self->start_event_obj;
-        res = PyTuple_New(2);
-        if (res) {
-            Py_INCREF(action); PyTuple_SET_ITEM(res, 0, (PyObject*) action);
-            Py_INCREF(node);   PyTuple_SET_ITEM(res, 1, (PyObject*) node);
-            PyList_Append(self->events, res);
-            Py_DECREF(res);
-        } else
-            PyErr_Clear(); /* FIXME: propagate error */
-    }
+    if (treebuilder_append_event(self, self->start_event_obj, node) < 0)
+        goto error;
 
     return node;
 
@@ -1885,63 +1892,13 @@ treebuilder_handle_end(TreeBuilderObject* self, PyObject* tag)
     self->last = (ElementObject*) self->this;
     self->this = (ElementObject*) item;
 
-    if (self->end_event_obj) {
-        PyObject* res;
-        PyObject* action = self->end_event_obj;
-        PyObject* node = (PyObject*) self->last;
-        res = PyTuple_New(2);
-        if (res) {
-            Py_INCREF(action); PyTuple_SET_ITEM(res, 0, (PyObject*) action);
-            Py_INCREF(node);   PyTuple_SET_ITEM(res, 1, (PyObject*) node);
-            PyList_Append(self->events, res);
-            Py_DECREF(res);
-        } else
-            PyErr_Clear(); /* FIXME: propagate error */
-    }
+    if (treebuilder_append_event(self, self->end_event_obj, (PyObject*)self->last) < 0)
+        return NULL;
 
     Py_INCREF(self->last);
     return (PyObject*) self->last;
 }
 
-LOCAL(void)
-treebuilder_handle_namespace(TreeBuilderObject* self, int start,
-                             PyObject *prefix, PyObject *uri)
-{
-    PyObject* res;
-    PyObject* action;
-    PyObject* parcel;
-
-    if (!self->events)
-        return;
-
-    if (start) {
-        if (!self->start_ns_event_obj)
-            return;
-        action = self->start_ns_event_obj;
-        parcel = Py_BuildValue("OO", prefix, uri);
-        if (!parcel)
-            return;
-        Py_INCREF(action);
-    } else {
-        if (!self->end_ns_event_obj)
-            return;
-        action = self->end_ns_event_obj;
-        Py_INCREF(action);
-        parcel = Py_None;
-        Py_INCREF(parcel);
-    }
-
-    res = PyTuple_New(2);
-
-    if (res) {
-        PyTuple_SET_ITEM(res, 0, action);
-        PyTuple_SET_ITEM(res, 1, parcel);
-        PyList_Append(self->events, res);
-        Py_DECREF(res);
-    } else
-        PyErr_Clear(); /* FIXME: propagate error */
-}
-
 /* -------------------------------------------------------------------- */
 /* methods (in alphabetical order) */
 
@@ -2367,8 +2324,16 @@ static void
 expat_start_ns_handler(XMLParserObject* self, const XML_Char* prefix,
                        const XML_Char *uri)
 {
-    PyObject* sprefix = NULL;
-    PyObject* suri = NULL;
+    TreeBuilderObject *target = (TreeBuilderObject*) self->target;
+    PyObject *parcel;
+    PyObject *sprefix = NULL;
+    PyObject *suri = NULL;
+
+    if (PyErr_Occurred())
+        return;
+
+    if (!target->events || !target->start_ns_event_obj)
+        return;
 
     if (uri)
         suri = makestring(uri, strlen(uri));
@@ -2386,20 +2351,27 @@ expat_start_ns_handler(XMLParserObject* self, const XML_Char* prefix,
         return;
     }
 
-    treebuilder_handle_namespace(
-        (TreeBuilderObject*) self->target, 1, sprefix, suri
-        );
-
+    parcel = PyTuple_Pack(2, sprefix, suri);
     Py_DECREF(sprefix);
     Py_DECREF(suri);
+    if (!parcel)
+        return;
+    treebuilder_append_event(target, target->start_ns_event_obj, parcel);
+    Py_DECREF(parcel);
 }
 
 static void
 expat_end_ns_handler(XMLParserObject* self, const XML_Char* prefix_in)
 {
-    treebuilder_handle_namespace(
-        (TreeBuilderObject*) self->target, 0, NULL, NULL
-        );
+    TreeBuilderObject *target = (TreeBuilderObject*) self->target;
+
+    if (PyErr_Occurred())
+        return;
+
+    if (!target->events)
+        return;
+
+    treebuilder_append_event(target, target->end_ns_event_obj, Py_None);
 }
 
 static void