From 21df02e499290e4041f7b1b75443bbef3980b6a4 Mon Sep 17 00:00:00 2001
From: Peter Hutterer <peter.hutterer@who-t.net>
Date: Wed, 8 Feb 2023 13:17:47 +1000
Subject: [PATCH] protocol: add the "bitmask" enum type and check for it

Plus check for duplicate values in enums
---
 proto/protocol.xml |  4 ++--
 proto/scanner.py   | 39 ++++++++++++++++++++++++++++++++++-----
 2 files changed, 36 insertions(+), 7 deletions(-)

diff --git a/proto/protocol.xml b/proto/protocol.xml
index f37af85..bcedebd 100644
--- a/proto/protocol.xml
+++ b/proto/protocol.xml
@@ -311,7 +311,7 @@
       </description>
     </request>
 
-    <enum name="capabilities" since="1">
+    <enum name="capabilities" since="1" type="bitmask">
       <description summary="Seat capabilities">
         A set of capabilities possible available on this seat. A client may bind to these
         capabilies and an EIS implementation may then create device based on the bound
@@ -417,7 +417,7 @@
       <arg name="name" type="string" help="the device name"/>
     </event>
 
-    <enum name="capabilities" since="1">
+    <enum name="capabilities" since="1" type="bitmask">
       <entry name="pointer" value="2"/>
       <entry name="pointer_absolute" value="4"/>
       <entry name="keyboard" value="8"/>
diff --git a/proto/scanner.py b/proto/scanner.py
index 7a61a2f..8211dd8 100755
--- a/proto/scanner.py
+++ b/proto/scanner.py
@@ -183,14 +183,27 @@ class Enum:
     name: str = attr.ib()
     since: int = attr.ib()
     interface: "Interface" = attr.ib()
+    is_bitmask: bool = attr.ib(default=False)
 
     entries: list[Entry] = attr.ib(init=False, factory=list)
 
     @classmethod
-    def create(cls, name: str, interface: "Interface", since: int = 1) -> "Enum":
-        return cls(name=name, since=since, interface=interface)
+    def create(
+        cls, name: str, interface: "Interface", since: int = 1, is_bitmask: bool = False
+    ) -> "Enum":
+        return cls(name=name, since=since, interface=interface, is_bitmask=is_bitmask)
 
     def add_entry(self, entry: Entry) -> None:
+        for e in self.entries:
+            if e.value == entry.value:
+                raise ValueError(f"Duplicate enum value {entry.value}")
+
+            if self.is_bitmask:
+                if e.value < 0:
+                    raise ValueError("Bitmasks must not be less than zero")
+                if e.value.bit_count() > 1:
+                    raise ValueError("Bitmasks must have exactly one bit set")
+
         self.entries.append(entry)
 
     @property
@@ -376,7 +389,20 @@ class Protocol(xml.sax.handler.ContentHandler):
                     *self.location, f"Missing attribute {e} in element '{element}'"
                 )
 
-            enum = Enum.create(name=name, since=since, interface=self.current_interface)
+            enum_type = attrs.get("type", None)
+            if enum_type is not None and enum_type not in ["bitmask"]:
+                raise XmlError(
+                    *self.location,
+                    f"Invalid enum type {enum_type} in element '{element}'",
+                )
+            is_bitmask = enum_type == "bitmask"
+
+            enum = Enum.create(
+                name=name,
+                since=since,
+                interface=self.current_interface,
+                is_bitmask=is_bitmask,
+            )
             self.current_interface.add_enum(enum)
             self.current_message = enum
         elif element == "arg":
@@ -414,10 +440,13 @@ class Protocol(xml.sax.handler.ContentHandler):
                     *self.location, f"Invalid element '{element}' must be inside <enum>"
                 )
             name = attrs["name"]
-            value = attrs["value"]
+            value = int(attrs["value"])
             summary = attrs.get("summary", "")
             entry = Entry.create(name=name, value=value, summary=summary)
-            self.current_message.add_entry(entry)
+            try:
+                self.current_message.add_entry(entry)
+            except ValueError as e:
+                raise XmlError(*self.location, str(e))
 
     def endElement(self, name):
         if name == "interface":