qapi: Pseudo-type '**' is now unused, drop it

'gen': false needs to stay for now, because netdev_add is still using
it.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NDaniel P. Berrange <berrange@redhat.com>
Message-Id: <1442401589-24189-25-git-send-email-armbru@redhat.com>

docs/qapi-code-gen.txt

@@ -111,10 +111,7 @@ and field names within a type, should be all lower case with words
 separated by a hyphen.  However, some existing older commands and
 complex types use underscore; when extending such expressions,
 consistency is preferred over blindly avoiding underscore.  Event
-names should be ALL_CAPS with words separated by underscore.  The
-special string '**' appears for some commands that manually perform
-their own type checking rather than relying on the type-safe code
-produced by the qapi code generators.
+names should be ALL_CAPS with words separated by underscore.
 
 Any name (command, event, type, field, or enum value) beginning with
 "x-" is marked experimental, and may be withdrawn or changed
@@ -461,14 +458,11 @@ which would validate this Client JSON Protocol transaction:
  <= { "return": [ { "value": "one" }, { } ] }
 
 In rare cases, QAPI cannot express a type-safe representation of a
-corresponding Client JSON Protocol command.  In these cases, if the
-command expression includes the key 'gen' with boolean value false,
-then the 'data' or 'returns' member that intends to bypass generated
-type-safety and do its own manual validation should use an inline
-dictionary definition, with a value of '**' rather than a valid type
-name for the keys that the generated code will not validate.  Please
-try to avoid adding new commands that rely on this, and instead use
-type-safe unions.  For an example of bypass usage:
+corresponding Client JSON Protocol command.  You then have to suppress
+generation of a marshalling function by including a key 'gen' with
+boolean value false, and instead write your own function.  Please try
+to avoid adding new commands that rely on this, and instead use
+type-safe unions.  For an example of this usage:
 
  { 'command': 'netdev_add',
    'data': {'type': 'str', 'id': 'str'},

scripts/qapi.py

@@ -428,15 +428,12 @@ def is_enum(name):
 
 def check_type(expr_info, source, value, allow_array = False,
                allow_dict = False, allow_optional = False,
-               allow_star = False, allow_metas = []):
+               allow_metas = []):
     global all_names
 
     if value is None:
         return
 
-    if allow_star and value == '**':
-        return
-
     # Check if array type for value is okay
     if isinstance(value, list):
         if not allow_array:
@@ -450,10 +447,6 @@ def check_type(expr_info, source, value, allow_array = False,
 
     # Check if type name for value is okay
     if isinstance(value, str):
-        if value == '**':
-            raise QAPIExprError(expr_info,
-                                "%s uses '**' but did not request 'gen':false"
-                                % source)
         if not value in all_names:
             raise QAPIExprError(expr_info,
                                 "%s uses unknown type '%s'"
@@ -479,7 +472,7 @@ def check_type(expr_info, source, value, allow_array = False,
         # Todo: allow dictionaries to represent default values of
         # an optional argument.
         check_type(expr_info, "Member '%s' of %s" % (key, source), arg,
-                   allow_array=True, allow_star=allow_star,
+                   allow_array=True,
                    allow_metas=['built-in', 'union', 'alternate', 'struct',
                                 'enum'])
 
@@ -499,18 +492,16 @@ def check_member_clash(expr_info, base_name, data, source = ""):
 
 def check_command(expr, expr_info):
     name = expr['command']
-    allow_star = expr.has_key('gen')
 
     check_type(expr_info, "'data' for command '%s'" % name,
                expr.get('data'), allow_dict=True, allow_optional=True,
-               allow_metas=['struct'], allow_star=allow_star)
+               allow_metas=['struct'])
     returns_meta = ['union', 'struct']
     if name in returns_whitelist:
         returns_meta += ['built-in', 'alternate', 'enum']
     check_type(expr_info, "'returns' for command '%s'" % name,
                expr.get('returns'), allow_array=True,
-               allow_optional=True, allow_metas=returns_meta,
-               allow_star=allow_star)
+               allow_optional=True, allow_metas=returns_meta)
 
 def check_event(expr, expr_info):
     global events
@@ -1122,7 +1113,6 @@ class QAPISchema(object):
                   ('bool',   'boolean', 'bool',     'false'),
                   ('any',    'value',   'QObject' + pointer_suffix, 'NULL')]:
             self._def_builtin_type(*t)
-        self._entity_dict['**'] = self.lookup_type('any') # TODO drop this alias
 
     def _make_implicit_enum_type(self, name, values):
         name = name + 'Kind'
@@ -1272,8 +1262,6 @@ class QAPISchema(object):
     def visit(self, visitor):
         visitor.visit_begin(self)
         for name in sorted(self._entity_dict.keys()):
-            if self._entity_dict[name].name != name:
-                continue        # ignore alias TODO drop alias and remove
             self._entity_dict[name].visit(visitor)
         visitor.visit_end()
 

tests/Makefile

@@ -234,7 +234,7 @@ check-qapi-schema-y := $(addprefix tests/qapi-schema/, \
 	bad-type-dict.json double-data.json unknown-expr-key.json \
 	redefined-type.json redefined-command.json redefined-builtin.json \
 	redefined-event.json command-int.json bad-data.json event-max.json \
-	type-bypass.json type-bypass-no-gen.json type-bypass-bad-gen.json \
+	type-bypass-bad-gen.json \
 	args-invalid.json \
 	args-array-empty.json args-array-unknown.json args-int.json \
 	args-unknown.json args-member-unknown.json args-member-array.json \

tests/qapi-schema/type-bypass-no-gen.err

-tests/qapi-schema/type-bypass-no-gen.json:2: Member 'arg' of 'data' for command 'unsafe' uses '**' but did not request 'gen':false

tests/qapi-schema/type-bypass-no-gen.exit

-1

tests/qapi-schema/type-bypass-no-gen.json

-# type bypass only works with 'gen':false
-{ 'command': 'unsafe', 'data': { 'arg': '**' }, 'returns': '**' }

tests/qapi-schema/type-bypass.exit

-0

tests/qapi-schema/type-bypass.json

-# Use of 'gen':false allows bypassing type system
-{ 'command': 'unsafe', 'data': { 'arg': '**' }, 'returns': '**', 'gen': false }

tests/qapi-schema/type-bypass.out

-object :obj-unsafe-arg
-    member arg: any optional=False
-command unsafe :obj-unsafe-arg -> any
-   gen=False success_response=True