scanner: parse the copyright tag

proto/ei-scanner

@@ -374,8 +374,15 @@ class XmlError(Exception):
         return cls(line=location[0], column=location[1], message=message)
 
 
+@attr.s
+class Copyright:
+    text: str = attr.ib(default="")
+    is_complete: bool = attr.ib(init=False, default=False)
+
+
 @attr.s
 class Protocol:
+    copyright: Optional[str] = attr.ib(default=None)
     interfaces: list[Interface] = attr.ib(factory=list)
 
 
@@ -387,6 +394,7 @@ class ProtocolParser(xml.sax.handler.ContentHandler):
     current_interface: Optional[Interface] = attr.ib(init=False, default=None)
     current_message: Optional[Union[Message, Enum]] = attr.ib(init=False, default=None)
     current_description: Optional[Description] = attr.ib(init=False, default=None)
+    copyright: Optional[Copyright] = attr.ib(init=False, default=None)
 
     _run_counter: int = attr.ib(init=False, default=0, repr=False)
 
@@ -612,6 +620,12 @@ class ProtocolParser(xml.sax.handler.ContentHandler):
         elif element == "description":
             summary = attrs.get("summary", "")
             self.current_description = Description(summary=summary)
+        elif element == "copyright":
+            if self.copyright is not None:
+                raise XmlError.create(
+                    "Multiple <copyright> tags in file", self.location
+                )
+            self.copyright = Copyright()
 
     def endElement(self, name):
         if name == "interface":
@@ -640,11 +654,16 @@ class ProtocolParser(xml.sax.handler.ContentHandler):
             else:
                 self.current_message.description = self.current_description
             self.current_description = None
+        elif name == "copyright":
+            assert self.copyright is not None
+            self.copyright.text = dedent(self.copyright.text)
+            self.copyright.is_complete = True
 
     def characters(self, content):
         if self.current_description is not None:
             self.current_description.text += content
-        pass
+        elif self.copyright is not None and not self.copyright.is_complete:
+            self.copyright.text += content
 
     @classmethod
     def create(cls, component: str) -> "ProtocolParser":
@@ -657,7 +676,8 @@ def parse(protofile: Path, component: str) -> Protocol:
     xml.sax.parse(os.fspath(protofile), proto)
     # We parse two times, once to fetch all the interfaces, then to parse the details
     xml.sax.parse(os.fspath(protofile), proto)
-    return Protocol(proto.interfaces)
+    copyright = proto.copyright.text if proto.copyright else None
+    return Protocol(copyright=copyright, interfaces=proto.interfaces)
 
 
 def generate_source(