[Libguestfs] [PATCH nbdkit] python: Allow extents to return any iterable (which includes lists).
Thanks: Nir Soffer.
Enhances: commit c12e3cb150259f0058727a50341a2d14bb0015a3
---
plugins/python/nbdkit-python-plugin.pod | 3 +-
plugins/python/python.c | 39 +++++++++++++++----------
2 files changed, 25 insertions(+), 17 deletions(-)
diff --git a/plugins/python/nbdkit-python-plugin.pod
b/plugins/python/nbdkit-python-plugin.pod
index d7b6033f..ddae677e 100644
--- a/plugins/python/nbdkit-python-plugin.pod
+++ b/plugins/python/nbdkit-python-plugin.pod
@@ -377,7 +377,8 @@ optionally using C<nbdkit.set_error> first.
(Optional)
def extents(h, count, offset, flags):
- # return a list of (offset, length, type) tuples:
+ # return an iterable object (eg. list) of
+ # (offset, length, type) tuples:
return [ (off1, len1, type1), (off2, len2, type2), ... ]
=back
diff --git a/plugins/python/python.c b/plugins/python/python.c
index 46b912e2..27c5ede2 100644
--- a/plugins/python/python.c
+++ b/plugins/python/python.c
@@ -1035,7 +1035,8 @@ py_extents (void *handle, uint32_t count, uint64_t offset,
struct handle *h = handle;
PyObject *fn;
PyObject *r;
- Py_ssize_t i, size;
+ PyObject *iter, *t;
+ size_t size;
if (callback_defined ("extents", &fn)) {
PyErr_Clear ();
@@ -1045,29 +1046,25 @@ py_extents (void *handle, uint32_t count, uint64_t offset,
if (check_python_failure ("extents") == -1)
return -1;
- /* We expect a list of extents to be returned. Each extent is a
- * tuple (offset, length, type). The list must not be empty.
- */
- if (!PyList_Check (r)) {
- nbdkit_error ("extents method did not return a list");
- Py_DECREF (r);
- return -1;
- }
- size = PyList_Size (r);
- if (size < 1) {
- nbdkit_error ("extents method cannot return an empty list");
+ iter = PyObject_GetIter (r);
+ if (iter == NULL) {
+ nbdkit_error ("extents method did not return "
+ "something which is iterable");
Py_DECREF (r);
return -1;
}
- for (i = 0; i < size; ++i) {
- PyObject *t, *py_offset, *py_length, *py_type;
+ size = 0;
+ while ((t = PyIter_Next (iter)) != NULL) {
+ PyObject *py_offset, *py_length, *py_type;
uint64_t extent_offset, extent_length;
uint32_t extent_type;
- t = PyList_GetItem (r, i);
+ size++;
+
if (!PyTuple_Check (t) || PyTuple_Size (t) != 3) {
- nbdkit_error ("extents method did not return a list of 3-tuples");
+ nbdkit_error ("extents method did not return an iterable of
3-tuples");
+ Py_DECREF (iter);
Py_DECREF (r);
return -1;
}
@@ -1078,16 +1075,26 @@ py_extents (void *handle, uint32_t count, uint64_t offset,
extent_length = PyLong_AsUnsignedLongLong (py_length);
extent_type = PyLong_AsUnsignedLong (py_type);
if (check_python_failure ("PyLong") == -1) {
+ Py_DECREF (iter);
Py_DECREF (r);
return -1;
}
if (nbdkit_add_extent (extents,
extent_offset, extent_length, extent_type) == -1) {
+ Py_DECREF (iter);
Py_DECREF (r);
return -1;
}
}
+ if (size < 1) {
+ nbdkit_error ("extents method cannot return an empty list");
+ Py_DECREF (iter);
+ Py_DECREF (r);
+ return -1;
+ }
+
+ Py_DECREF (iter);
Py_DECREF (r);
}
else {
--
2.27.0