1 files changed, 100 insertions, 0 deletions
diff --git a/python/weenix/list.py b/python/weenix/list.py
new file mode 100644
index 0000000..6f951ae
--- /dev/null
+++ b/python/weenix/list.py
@@ -0,0 +1,100 @@
+import gdb
+import weenix
+
+_char_type = gdb.lookup_type("char")
+_list_type = gdb.lookup_type("list_t")
+_list_link_type = gdb.lookup_type("list_link_t")
+
+class Link:
+
+	def __init__(self, value, dtype=None, dmemb=None):
+		self._value = value
+		self._dtype = dtype
+		self._dmemb = dmemb
+
+	def value(self):
+		return self._value
+
+	def item(self, typ=None, memb=None):
+		if (typ == None):
+			typ = self._dtype
+		if (memb == None):
+			memb = self._dmemb
+		if (typ == None or memb == None):
+			raise RuntimeError("list reference requires "
+							   "both type and member name")
+
+		for field in gdb.lookup_type(typ).fields():
+			if (field.name == memb):
+				link = self._value.address.cast(_char_type.pointer())
+				link -= (field.bitpos // 8)
+				link = link.cast(gdb.lookup_type(typ).pointer())
+				return link.dereference()
+		raise weenix.WeenixError("no member {0} of {1}"
+								 .format(memb, typ))
+
+	def link_addr(self):
+		return self._value.address
+
+class List:
+
+	def __init__(self, value, dtype=None, dmemb=None):
+		self._value = value
+		self._dtype = dtype
+		self._dmemb = dmemb
+
+	def __iter__(self):
+		curr = self._value["l_next"].dereference()
+		while (curr.address != self._value.address):
+			yield Link(curr, self._dtype, self._dmemb)
+			curr = curr["l_next"].dereference()
+		raise StopIteration
+
+	def __len__(self):
+		try:
+			return self.__count
+		except AttributeError:
+			self.__count = 0
+			curr = self._value["l_next"].dereference()
+			while (curr.address != self._value.address):
+				curr = curr["l_next"].dereference()
+				self.__count += 1
+			return self.__count
+
+	def __getitem__(self, key):
+		if (type(key) != int):
+			raise TypeError(key)
+
+		for i, item in enumerate(self):
+			if (i == key):
+				return item
+		raise IndexError(key)
+
+def load(name, dtype=None, dmemb=None):
+	weenix.assert_type(name, _list_type)
+
+	if (dtype != None):
+		try:
+			if (not isinstance(dtype, gdb.Type)):
+				typ = gdb.lookup_type(dtype)
+			else:
+				typ = dtype
+		except RuntimeError:
+			raise gdb.GdbError("no such type: {0}".format(dtype))
+	
+		found = False
+		for field in typ.strip_typedefs().fields():
+			if (field.name == dmemb):
+				try:
+					weenix.assert_type(field.type, _list_link_type)
+				except gdb.GdbError as err:
+					raise gdb.GdbError(
+						"field '{0}' of type '{1}' has wrong type: {2}"
+						.format(dmemb, dtype, str(err)))
+				found = True
+		if (not found):
+			raise gdb.GdbError("'{0}' type does not contain field '{1}'"
+							   .format(dtype, dmemb))
+
+	value = name if isinstance(name, gdb.Value) else gdb.parse_and_eval(name)
+	return List(value, dtype, dmemb)