qapi: Check for member name conflicts with a base class
Our type inheritance for both 'struct' and for flat 'union' merges
key/value pairs from the base class with those from the type in
question. Although the C code currently boxes things so that there
is a distinction between which member is referred to, the QMP wire
format does not allow passing a key more than once in a single
object. Besides, if we ever change the generated C code to not be
quite so boxy, we'd want to avoid duplicate member names there,
too.
Fix a testsuite entry added in an earlier patch, as well as adding
a couple more tests to ensure we have appropriate coverage. Ensure
that collisions are detected, regardless of whether there is a
difference in opinion on whether the member name is optional.
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
diff --git a/scripts/qapi.py b/scripts/qapi.py
index 6a9aa24..166b74f 100644
--- a/scripts/qapi.py
+++ b/scripts/qapi.py
@@ -414,6 +414,20 @@
allow_metas=['built-in', 'union', 'alternate', 'struct',
'enum'])
+def check_member_clash(expr_info, base_name, data, source = ""):
+ base = find_struct(base_name)
+ assert base
+ base_members = base['data']
+ for key in data.keys():
+ if key.startswith('*'):
+ key = key[1:]
+ if key in base_members or "*" + key in base_members:
+ raise QAPIExprError(expr_info,
+ "Member name '%s'%s clashes with base '%s'"
+ % (key, source, base_name))
+ if base.get('base'):
+ check_member_clash(expr_info, base['base'], data, source)
+
def check_command(expr, expr_info):
name = expr['command']
allow_star = expr.has_key('gen')
@@ -503,9 +517,14 @@
check_name(expr_info, "Member of union '%s'" % name, key)
# Each value must name a known type; furthermore, in flat unions,
- # branches must be a struct
+ # branches must be a struct with no overlapping member names
check_type(expr_info, "Member '%s' of union '%s'" % (key, name),
value, allow_array=True, allow_metas=allow_metas)
+ if base:
+ branch_struct = find_struct(value)
+ assert branch_struct
+ check_member_clash(expr_info, base, branch_struct['data'],
+ " of branch '%s'" % key)
# If the discriminator names an enum type, then all members
# of 'data' must also be members of the enum type.
@@ -582,6 +601,8 @@
allow_dict=True, allow_optional=True)
check_type(expr_info, "'base' for struct '%s'" % name, expr.get('base'),
allow_metas=['struct'])
+ if expr.get('base'):
+ check_member_clash(expr_info, expr['base'], expr['data'])
def check_exprs(schema):
for expr_elem in schema.exprs:
