Add Babeltrace 2 Python bindings

[babeltrace.git] / bindings / python / bt2 / notification_iterator.py

diff --git a/bindings/python/bt2/notification_iterator.py b/bindings/python/bt2/notification_iterator.py
new file mode 100644 (file)
index 0000000..e0d0b0c
--- /dev/null
+++ b/bindings/python/bt2/notification_iterator.py
@@ -0,0 +1,115 @@
+# The MIT License (MIT)
+#
+# Copyright (c) 2017 Philippe Proulx <pproulx@efficios.com>
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in
+# all copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+# THE SOFTWARE.
+
+from bt2 import native_bt, object, utils
+import bt2.notification
+import collections.abc
+import bt2.component
+import bt2
+
+
+class NotificationIteratorSeekOrigin:
+    BEGIN = native_bt.NOTIFICATION_ITERATOR_SEEK_ORIGIN_BEGIN
+    CURRENT = native_bt.NOTIFICATION_ITERATOR_SEEK_ORIGIN_CURRENT
+    END = native_bt.NOTIFICATION_ITERATOR_SEEK_ORIGIN_END
+
+
+class _GenericNotificationIteratorMethods(collections.abc.Iterator):
+    @property
+    def notification(self):
+        notif_ptr = native_bt.notification_iterator_get_notification(self._ptr)
+        utils._handle_ptr(notif_ptr, "cannot get notification iterator object's current notification object")
+        return bt2.notification._create_from_ptr(notif_ptr)
+
+    def _handle_status(self, status, gen_error_msg):
+        if status == native_bt.NOTIFICATION_ITERATOR_STATUS_END:
+            raise bt2.Stop
+        elif status == native_bt.NOTIFICATION_ITERATOR_STATUS_UNSUPPORTED:
+            raise bt2.UnsupportedFeature
+        elif status < 0:
+            raise bt2.Error(gen_error_msg)
+
+    def next(self):
+        status = native_bt.notification_iterator_next(self._ptr)
+        self._handle_status(status,
+                            'unexpected error: cannot go to the next notification')
+
+    def __next__(self):
+        self.next()
+        return self.notification
+
+    def seek_to_time(self, origin, time):
+        utils._check_int64(origin)
+        utils._check_int64(time)
+        status = native_bt.notification_iterator_seek_time(self._ptr, origin,
+                                                           time)
+        self._handle_status(status,
+                            'unexpected error: cannot seek notification iterator to time')
+
+
+class _GenericNotificationIterator(object._Object, _GenericNotificationIteratorMethods):
+    @property
+    def component(self):
+        comp_ptr = native_bt.notification_iterator_get_component(self._ptr)
+        utils._handle_ptr(comp_ptr, "cannot get notification iterator object's component object")
+        return bt2.component._create_generic_component_from_ptr(comp_ptr)
+
+
+class UserNotificationIterator(_GenericNotificationIteratorMethods):
+    def __new__(cls, ptr):
+        # User iterator objects are always created by the BT system,
+        # that is, never instantiated directly by Python code.
+        #
+        # The system calls this, then manually calls self.__init__()
+        # without the `ptr` argument. The user has access to
+        # self.component during this call, thanks to this self._ptr
+        # argument being set.
+        #
+        # self._ptr is NOT owned by this object here, so there's nothing
+        # to do in __del__().
+        self = super().__new__(cls)
+        self._ptr = ptr
+        return self
+
+    def __init__(self):
+        pass
+
+    @property
+    def component(self):
+        return native_bt.py3_get_component_from_notif_iter(self._ptr)
+
+    @property
+    def addr(self):
+        return int(self._ptr)
+
+    def _destroy(self):
+        pass
+
+    def _get_from_bt(self):
+        # this can raise anything: it's catched by the system
+        notif = self._get()
+        utils._check_type(notif, bt2.notification._Notification)
+
+        # steal the underlying native notification object for the caller
+        notif_ptr = notif._ptr
+        notif._ptr = None
+        return int(notif_ptr)