qapi-types: add #if conditions to types & visitors

Types & visitors are coupled and must be handled together to avoid
temporary build regression.

Wrap generated types/visitor code with #if/#endif using the context
helpers. Derived from a patch by Marc-André.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <20180703155648.11933-12-marcandre.lureau@redhat.com>

scripts/qapi/types.py

@@ -55,7 +55,7 @@ def gen_struct_members(members):
     return ret
 
 
-def gen_object(name, base, members, variants):
+def gen_object(name, ifcond, base, members, variants):
     if name in objects_seen:
         return ''
     objects_seen.add(name)
@@ -64,11 +64,14 @@ def gen_object(name, base, members, variants):
     if variants:
         for v in variants.variants:
             if isinstance(v.type, QAPISchemaObjectType):
-                ret += gen_object(v.type.name, v.type.base,
+                ret += gen_object(v.type.name, v.type.ifcond, v.type.base,
                                   v.type.local_members, v.type.variants)
 
     ret += mcgen('''
 
+''')
+    ret += gen_if(ifcond)
+    ret += mcgen('''
 struct %(c_name)s {
 ''',
                  c_name=c_name(name))
@@ -101,6 +104,7 @@ struct %(c_name)s {
     ret += mcgen('''
 };
 ''')
+    ret += gen_endif(ifcond)
 
     return ret
 
@@ -209,10 +213,12 @@ class QAPISchemaGenTypeVisitor(QAPISchemaModularCVisitor):
         self._genc.add(gen_type_cleanup(name))
 
     def visit_enum_type(self, name, info, ifcond, values, prefix):
+        with ifcontext(ifcond, self._genh, self._genc):
             self._genh.preamble_add(gen_enum(name, values, prefix))
             self._genc.add(gen_enum_lookup(name, values, prefix))
 
     def visit_array_type(self, name, info, ifcond, element_type):
+        with ifcontext(ifcond, self._genh, self._genc):
             self._genh.preamble_add(gen_fwd_object_or_array(name))
             self._genh.add(gen_array(name, element_type))
             self._gen_type_cleanup(name)
@@ -221,8 +227,10 @@ class QAPISchemaGenTypeVisitor(QAPISchemaModularCVisitor):
         # Nothing to do for the special empty builtin
         if name == 'q_empty':
             return
+        with ifcontext(ifcond, self._genh):
             self._genh.preamble_add(gen_fwd_object_or_array(name))
-        self._genh.add(gen_object(name, base, members, variants))
+        self._genh.add(gen_object(name, ifcond, base, members, variants))
+        with ifcontext(ifcond, self._genh, self._genc):
             if base and not base.is_implicit():
                 self._genh.add(gen_upcast(name, base))
             # TODO Worth changing the visitor signature, so we could
@@ -232,9 +240,11 @@ class QAPISchemaGenTypeVisitor(QAPISchemaModularCVisitor):
                 self._gen_type_cleanup(name)
 
     def visit_alternate_type(self, name, info, ifcond, variants):
+        with ifcontext(ifcond, self._genh):
             self._genh.preamble_add(gen_fwd_object_or_array(name))
-        self._genh.add(gen_object(name, None,
+        self._genh.add(gen_object(name, ifcond, None,
                                   [variants.tag_member], variants))
+        with ifcontext(ifcond, self._genh, self._genc):
             self._gen_type_cleanup(name)
 
 

scripts/qapi/visit.py

@@ -311,10 +311,12 @@ class QAPISchemaGenVisitVisitor(QAPISchemaModularCVisitor):
                                       types=types))
 
     def visit_enum_type(self, name, info, ifcond, values, prefix):
+        with ifcontext(ifcond, self._genh, self._genc):
             self._genh.add(gen_visit_decl(name, scalar=True))
             self._genc.add(gen_visit_enum(name))
 
     def visit_array_type(self, name, info, ifcond, element_type):
+        with ifcontext(ifcond, self._genh, self._genc):
             self._genh.add(gen_visit_decl(name))
             self._genc.add(gen_visit_list(name, element_type))
 
@@ -322,8 +324,10 @@ class QAPISchemaGenVisitVisitor(QAPISchemaModularCVisitor):
         # Nothing to do for the special empty builtin
         if name == 'q_empty':
             return
+        with ifcontext(ifcond, self._genh, self._genc):
             self._genh.add(gen_visit_members_decl(name))
-        self._genc.add(gen_visit_object_members(name, base, members, variants))
+            self._genc.add(gen_visit_object_members(name, base,
+                                                    members, variants))
             # TODO Worth changing the visitor signature, so we could
             # directly use rather than repeat type.is_implicit()?
             if not name.startswith('q_'):
@@ -332,6 +336,7 @@ class QAPISchemaGenVisitVisitor(QAPISchemaModularCVisitor):
                 self._genc.add(gen_visit_object(name, base, members, variants))
 
     def visit_alternate_type(self, name, info, ifcond, variants):
+        with ifcontext(ifcond, self._genh, self._genc):
             self._genh.add(gen_visit_decl(name))
             self._genc.add(gen_visit_alternate(name, variants))