feat: add optimized parser for InterfacesRemoved (#123)

bench/unmarshall_interfaces_removed.py

@@ -0,0 +1,31 @@
+import io
+import timeit
+
+from dbus_fast._private.unmarshaller import Unmarshaller
+
+#  cythonize -X language_level=3 -a -i  src/dbus_fast/_private/unmarshaller.py
+
+
+bluez_interfaces_removed_message = (
+    b'l\4\1\1\222\0\0\0\377@-\0~\0\0\0\1\1o\0\1\0\0\0/\0\0\0\0\0\0\0\2\1s\0"\0\0\0'
+    b"org.freedesktop.DBus.ObjectManager\0\0\0\0\0\0\3\1s\0\21\0\0\0InterfacesRemoved"
+    b"\0\0\0\0\0\0\0\10\1g\0\3oas\0\0\0\0\0\0\0\0\7\1s\0\5\0\0\0:1.12\0\0\0%\0\0\0"
+    b"/org/bluez/hci0/dev_5F_13_47_38_26_55\0\0\0b\0\0\0\37\0\0\0org.freedesktop.DBus"
+    b".Properties\0#\0\0\0org.freedesktop.DBus.Introspectable\0\21\0\0\0org.bluez.Dev"
+    b"ice1\0"
+)
+
+
+stream = io.BytesIO(bluez_interfaces_removed_message)
+unmarshaller = Unmarshaller(stream)
+
+
+def unmarshall_interfaces_removed_message():
+    stream.seek(0)
+    unmarshaller.reset()
+    unmarshaller.unmarshall()
+
+
+count = 3000000
+time = timeit.Timer(unmarshall_interfaces_removed_message).timeit(count)
+print(f"Unmarshalling {count} bluetooth InterfacesRemoved messages took {time} seconds")

src/dbus_fast/_private/unmarshaller.pxd

@@ -52,6 +52,8 @@ cdef object SIGNATURE_TREE_A_SV_TYPES_0
 cdef object SIGNATURE_TREE_SA_SV_AS
 cdef object SIGNATURE_TREE_SA_SV_AS_TYPES_1
 cdef object SIGNATURE_TREE_SA_SV_AS_TYPES_2
+cdef object SIGNATURE_TREE_OAS
+cdef object SIGNATURE_TREE_OAS_TYPES_1
 cdef object SIGNATURE_TREE_OA_SA_SV
 cdef object SIGNATURE_TREE_OA_SA_SV_TYPES_1
 cdef object SIGNATURE_TREE_AY

src/dbus_fast/_private/unmarshaller.py

@@ -70,6 +70,9 @@ SIGNATURE_TREE_AS_TYPES_0 = SIGNATURE_TREE_AS.types[0]
 SIGNATURE_TREE_A_SV = get_signature_tree("a{sv}")
 SIGNATURE_TREE_A_SV_TYPES_0 = SIGNATURE_TREE_A_SV.types[0]
 
+SIGNATURE_TREE_OAS = get_signature_tree("oas")
+SIGNATURE_TREE_OAS_TYPES_1 = SIGNATURE_TREE_OAS.types[1]
+
 SIGNATURE_TREE_AY_TYPES_0 = SIGNATURE_TREE_AY.types[0]
 SIGNATURE_TREE_A_QV = get_signature_tree("a{qv}")
 SIGNATURE_TREE_A_QV_TYPES_0 = SIGNATURE_TREE_A_QV.types[0]
@@ -417,8 +420,9 @@ class Unmarshaller:
         if token == "{":
             result_dict = {}
             beginning_pos = self._pos
-            child_0 = child_type.children[0]
+            children = child_type.children
-            child_1 = child_type.children[1]
+            child_0 = children[0]
+            child_1 = children[1]
             child_0_token = child_0.token
             child_1_token = child_1.token
             # Strings with variant values are the most common case
@@ -442,7 +446,6 @@ class Unmarshaller:
             else:
                 reader_1 = self._readers[child_1_token]
                 reader_0 = self._readers[child_0_token]
-
                 while self._pos - beginning_pos < array_length:
                     self._pos += -self._pos & 7  # align 8
                     key = reader_0(self, child_0)
@@ -455,7 +458,11 @@ class Unmarshaller:
 
         result_list = []
         beginning_pos = self._pos
-        reader = self._readers[child_type.token]
+        if token in "os":
+            while self._pos - beginning_pos < array_length:
+                result_list.append(self._read_string_unpack())
+            return result_list
+        reader = self._readers[token]
         while self._pos - beginning_pos < array_length:
             result_list.append(reader(self, child_type))
         return result_list
@@ -568,6 +575,12 @@ class Unmarshaller:
                 self._read_string_unpack(),
                 self._read_array(SIGNATURE_TREE_OA_SA_SV_TYPES_1),
             ]
+        elif signature == "oas":
+            tree = SIGNATURE_TREE_OAS
+            body = [
+                self._read_string_unpack(),
+                self._read_array(SIGNATURE_TREE_OAS_TYPES_1),
+            ]
         else:
             tree = get_signature_tree(signature)
             body = [self._readers[t.token](self, t) for t in tree.types]

tests/test_marshaller.py

@@ -321,6 +321,49 @@ def test_unmarshall_bluez_interfaces_added_message():
     ]
 
 
+def test_unmarshall_bluez_interfaces_removed_message():
+    bluez_interfaces_removed_message = (
+        b'l\4\1\1\222\0\0\0\377@-\0~\0\0\0\1\1o\0\1\0\0\0/\0\0\0\0\0\0\0\2\1s\0"\0\0\0'
+        b"org.freedesktop.DBus.ObjectManager\0\0\0\0\0\0\3\1s\0\21\0\0\0InterfacesRemoved"
+        b"\0\0\0\0\0\0\0\10\1g\0\3oas\0\0\0\0\0\0\0\0\7\1s\0\5\0\0\0:1.12\0\0\0%\0\0\0"
+        b"/org/bluez/hci0/dev_5F_13_47_38_26_55\0\0\0b\0\0\0\37\0\0\0org.freedesktop.DBus"
+        b".Properties\0#\0\0\0org.freedesktop.DBus.Introspectable\0\21\0\0\0org.bluez.Dev"
+        b"ice1\0"
+    )
+
+    stream = io.BytesIO(bluez_interfaces_removed_message)
+    unmarshaller = Unmarshaller(stream)
+    assert unmarshaller.unmarshall()
+    message = unmarshaller.message
+    assert message is not None
+    assert message.body == [
+        "/org/bluez/hci0/dev_5F_13_47_38_26_55",
+        [
+            "org.freedesktop.DBus.Properties",
+            "org.freedesktop.DBus.Introspectable",
+            "org.bluez.Device1",
+        ],
+    ]
+    assert message.sender == ":1.12"
+    assert message.path == "/"
+    assert message.interface == "org.freedesktop.DBus.ObjectManager"
+    assert message.member == "InterfacesRemoved"
+    assert message.signature == "oas"
+    assert message.message_type == MessageType.SIGNAL
+    assert message.flags == MessageFlag.NO_REPLY_EXPECTED
+    assert message.serial == 2965759
+    assert message.destination is None
+    unpacked = unpack_variants(message.body)
+    assert unpacked == [
+        "/org/bluez/hci0/dev_5F_13_47_38_26_55",
+        [
+            "org.freedesktop.DBus.Properties",
+            "org.freedesktop.DBus.Introspectable",
+            "org.bluez.Device1",
+        ],
+    ]
+
+
 def test_ay_buffer():
     body = [bytes(10000)]
     msg = Message(path="/test", member="test", signature="ay", body=body)