bt2: Mass notification -> message rename

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

diff --git a/bindings/python/bt2/bt2/message_iterator.py b/bindings/python/bt2/bt2/message_iterator.py
new file mode 100644 (file)
index 0000000..69b1c4f
--- /dev/null
+++ b/bindings/python/bt2/bt2/message_iterator.py
@@ -0,0 +1,121 @@
+# 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.message
+import collections.abc
+import bt2.component
+import bt2
+
+
+class _MessageIterator(collections.abc.Iterator):
+    def _handle_status(self, status, gen_error_msg):
+        if status == native_bt.MESSAGE_ITERATOR_STATUS_CANCELED:
+            raise bt2.MessageIteratorCanceled
+        elif status == native_bt.MESSAGE_ITERATOR_STATUS_AGAIN:
+            raise bt2.TryAgain
+        elif status == native_bt.MESSAGE_ITERATOR_STATUS_END:
+            raise bt2.Stop
+        elif status == native_bt.MESSAGE_ITERATOR_STATUS_UNSUPPORTED:
+            raise bt2.UnsupportedFeature
+        elif status < 0:
+            raise bt2.Error(gen_error_msg)
+
+    def __next__(self):
+        raise NotImplementedError
+
+
+class _GenericMessageIterator(object._Object, _MessageIterator):
+    def _get_msg(self):
+        msg_ptr = native_bt.message_iterator_get_message(self._ptr)
+        utils._handle_ptr(msg_ptr, "cannot get message iterator object's current message object")
+        return bt2.message._create_from_ptr(msg_ptr)
+
+    def _next(self):
+        status = native_bt.message_iterator_next(self._ptr)
+        self._handle_status(status,
+                            'unexpected error: cannot advance the message iterator')
+
+    def __next__(self):
+        self._next()
+        return self._get_msg()
+
+
+class _PrivateConnectionMessageIterator(_GenericMessageIterator):
+    @property
+    def component(self):
+        comp_ptr = native_bt.private_connection_message_iterator_get_component(self._ptr)
+        assert(comp_ptr)
+        return bt2.component._create_generic_component_from_ptr(comp_ptr)
+
+
+class _OutputPortMessageIterator(_GenericMessageIterator):
+    pass
+
+
+class _UserMessageIterator(_MessageIterator):
+    def __new__(cls, ptr):
+        # User iterator objects are always created by the native side,
+        # that is, never instantiated directly by Python code.
+        #
+        # The native code 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_user_component_from_user_msg_iter(self._ptr)
+
+    @property
+    def addr(self):
+        return int(self._ptr)
+
+    def _finalize(self):
+        pass
+
+    def __next__(self):
+        raise bt2.Stop
+
+    def _next_from_native(self):
+        # this can raise anything: it's catched by the native part
+        try:
+            msg = next(self)
+        except StopIteration:
+            raise bt2.Stop
+        except:
+            raise
+
+        utils._check_type(msg, bt2.message._Message)
+
+        # take a new reference for the native part
+        msg._get()
+        return int(msg._ptr)