]> git.proxmox.com Git - mirror_qemu.git/blobdiff - scripts/qapi.py
Merge remote-tracking branch 'remotes/kraxel/tags/pull-usb-20160720-1' into staging
[mirror_qemu.git] / scripts / qapi.py
index 296b9bb142ea96931d47ca0e52bdefa03884be1b..21bc32fda3d1e1d59f76d7b22c126deea236ea8c 100644 (file)
@@ -2,7 +2,7 @@
 # QAPI helper library
 #
 # Copyright IBM, Corp. 2011
-# Copyright (c) 2013-2015 Red Hat Inc.
+# Copyright (c) 2013-2016 Red Hat Inc.
 #
 # Authors:
 #  Anthony Liguori <aliguori@us.ibm.com>
@@ -33,7 +33,8 @@ builtin_types = {
     'uint32':   'QTYPE_QINT',
     'uint64':   'QTYPE_QINT',
     'size':     'QTYPE_QINT',
-    'any':      None,           # any qtype_code possible, actually
+    'any':      None,           # any QType possible, actually
+    'QType':    'QTYPE_QSTRING',
 }
 
 # Whitelist of commands allowed to return a non-dictionary
@@ -58,6 +59,18 @@ returns_whitelist = [
     'guest-sync-delimited',
 ]
 
+# Whitelist of entities allowed to violate case conventions
+case_whitelist = [
+    # From QMP:
+    'ACPISlotType',         # DIMM, visible through query-acpi-ospm-status
+    'CpuInfoMIPS',          # PC, visible through query-cpu
+    'CpuInfoTricore',       # PC, visible through query-cpu
+    'QapiErrorClass',       # all members, visible through errors
+    'UuidInfo',             # UUID, visible through query-uuid
+    'X86CPURegister32',     # all members, visible indirectly through qom-get
+    'q_obj_CpuInfo-base',   # CPU, visible through query-cpu
+]
+
 enum_types = []
 struct_types = []
 union_types = []
@@ -152,7 +165,7 @@ class QAPISchemaParser(object):
                     continue
                 try:
                     fobj = open(incl_abs_fname, 'r')
-                except IOError, e:
+                except IOError as e:
                     raise QAPIExprError(expr_info,
                                         '%s: %s' % (e.strerror, include))
                 exprs_include = QAPISchemaParser(fobj, previously_included,
@@ -313,7 +326,9 @@ class QAPISchemaParser(object):
 #
 
 
-def find_base_fields(base):
+def find_base_members(base):
+    if isinstance(base, dict):
+        return base
     base_struct_define = find_struct(base)
     if not base_struct_define:
         return None
@@ -342,20 +357,22 @@ def discriminator_find_enum_define(expr):
     if not (discriminator and base):
         return None
 
-    base_fields = find_base_fields(base)
-    if not base_fields:
+    base_members = find_base_members(base)
+    if not base_members:
         return None
 
-    discriminator_type = base_fields.get(discriminator)
+    discriminator_type = base_members.get(discriminator)
     if not discriminator_type:
         return None
 
     return find_enum(discriminator_type)
 
 
-# FIXME should enforce "other than downstream extensions [...], all
-# names should begin with a letter".
-valid_name = re.compile('^[a-zA-Z_][a-zA-Z0-9_.-]*$')
+# Names must be letters, numbers, -, and _.  They must start with letter,
+# except for downstream extensions which must start with __RFQDN_.
+# Dots are only valid in the downstream extension prefix.
+valid_name = re.compile('^(__[a-zA-Z0-9.-]+_)?'
+                        '[a-zA-Z][a-zA-Z0-9_-]*$')
 
 
 def check_name(expr_info, source, name, allow_optional=False,
@@ -374,9 +391,10 @@ def check_name(expr_info, source, name, allow_optional=False,
                                 % (source, name))
     # Enum members can start with a digit, because the generated C
     # code always prefixes it with the enum name
-    if enum_member:
-        membername = '_' + membername
-    # Reserve the entire 'q_' namespace for c_name()
+    if enum_member and membername[0].isdigit():
+        membername = 'D' + membername
+    # Reserve the entire 'q_' namespace for c_name(), and for 'q_empty'
+    # and 'q_obj_*' implicit type names.
     if not valid_name.match(membername) or \
        c_name(membername, False).startswith('q_'):
         raise QAPIExprError(expr_info,
@@ -502,27 +520,16 @@ def check_type(expr_info, source, value, allow_array=False,
                                 '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']
+    boxed = expr.get('boxed', False)
 
+    args_meta = ['struct']
+    if boxed:
+        args_meta += ['union', 'alternate']
     check_type(expr_info, "'data' for command '%s'" % name,
-               expr.get('data'), allow_dict=True, allow_optional=True,
-               allow_metas=['struct'])
+               expr.get('data'), allow_dict=not boxed, allow_optional=True,
+               allow_metas=args_meta)
     returns_meta = ['union', 'struct']
     if name in returns_whitelist:
         returns_meta += ['built-in', 'alternate', 'enum']
@@ -534,13 +541,15 @@ def check_command(expr, expr_info):
 def check_event(expr, expr_info):
     global events
     name = expr['event']
+    boxed = expr.get('boxed', False)
 
-    if name.upper() == 'MAX':
-        raise QAPIExprError(expr_info, "Event name 'MAX' cannot be created")
+    meta = ['struct']
+    if boxed:
+        meta += ['union', 'alternate']
     events.append(name)
     check_type(expr_info, "'data' for event '%s'" % name,
-               expr.get('data'), allow_dict=True, allow_optional=True,
-               allow_metas=['struct'])
+               expr.get('data'), allow_dict=not boxed, allow_optional=True,
+               allow_metas=meta)
 
 
 def check_union(expr, expr_info):
@@ -548,8 +557,6 @@ def check_union(expr, expr_info):
     base = expr.get('base')
     discriminator = expr.get('discriminator')
     members = expr['data']
-    values = {'MAX': '(automatic)', 'KIND': '(automatic)',
-              'TYPE': '(automatic)'}
 
     # Two types of unions, determined by discriminator.
 
@@ -564,21 +571,22 @@ def check_union(expr, expr_info):
 
     # Else, it's a flat union.
     else:
-        # The object must have a string member 'base'.
+        # The object must have a string or dictionary 'base'.
         check_type(expr_info, "'base' for union '%s'" % name,
-                   base, allow_metas=['struct'])
+                   base, allow_dict=True, allow_optional=True,
+                   allow_metas=['struct'])
         if not base:
             raise QAPIExprError(expr_info,
                                 "Flat union '%s' must have a base"
                                 % name)
-        base_fields = find_base_fields(base)
-        assert base_fields
+        base_members = find_base_members(base)
+        assert base_members
 
         # The value of member 'discriminator' must name a non-optional
         # member of the base struct.
         check_name(expr_info, "Discriminator of flat union '%s'" % name,
                    discriminator)
-        discriminator_type = base_fields.get(discriminator)
+        discriminator_type = base_members.get(discriminator)
         if not discriminator_type:
             raise QAPIExprError(expr_info,
                                 "Discriminator '%s' is not a member of base "
@@ -592,69 +600,57 @@ def check_union(expr, expr_info):
                                 "Discriminator '%s' must be of enumeration "
                                 "type" % discriminator)
 
-    # Check every branch
+    # Check every branch; don't allow an empty union
+    if len(members) == 0:
+        raise QAPIExprError(expr_info,
+                            "Union '%s' cannot have empty 'data'" % name)
     for (key, value) in members.items():
         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 with no overlapping member names
+        # Each value must name a known type
         check_type(expr_info, "Member '%s' of union '%s'" % (key, name),
                    value, allow_array=not base, 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, which in turn
-        # must not collide with the discriminator name.
+        # of 'data' must also be members of the enum type.
         if enum_define:
             if key not in enum_define['enum_values']:
                 raise QAPIExprError(expr_info,
                                     "Discriminator value '%s' is not found in "
                                     "enum '%s'" %
                                     (key, enum_define["enum_name"]))
-            if discriminator in enum_define['enum_values']:
-                raise QAPIExprError(expr_info,
-                                    "Discriminator name '%s' collides with "
-                                    "enum value in '%s'" %
-                                    (discriminator, enum_define["enum_name"]))
 
-        # Otherwise, check for conflicts in the generated enum
-        else:
-            c_key = camel_to_upper(key)
-            if c_key in values:
+    # If discriminator is user-defined, ensure all values are covered
+    if enum_define:
+        for value in enum_define['enum_values']:
+            if value not in members.keys():
                 raise QAPIExprError(expr_info,
-                                    "Union '%s' member '%s' clashes with '%s'"
-                                    % (name, key, values[c_key]))
-            values[c_key] = key
+                                    "Union '%s' data missing '%s' branch"
+                                    % (name, value))
 
 
 def check_alternate(expr, expr_info):
     name = expr['alternate']
     members = expr['data']
-    values = {'MAX': '(automatic)'}
     types_seen = {}
 
-    # Check every branch
+    # Check every branch; require at least two branches
+    if len(members) < 2:
+        raise QAPIExprError(expr_info,
+                            "Alternate '%s' should have at least two branches "
+                            "in 'data'" % name)
     for (key, value) in members.items():
         check_name(expr_info, "Member of alternate '%s'" % name, key)
 
-        # Check for conflicts in the generated enum
-        c_key = camel_to_upper(key)
-        if c_key in values:
-            raise QAPIExprError(expr_info,
-                                "Alternate '%s' member '%s' clashes with '%s'"
-                                % (name, key, values[c_key]))
-        values[c_key] = key
-
         # Ensure alternates have no type conflicts.
         check_type(expr_info, "Member '%s' of alternate '%s'" % (key, name),
                    value,
                    allow_metas=['built-in', 'union', 'struct', 'enum'])
         qtype = find_alternate_member_qtype(value)
-        assert qtype
+        if not qtype:
+            raise QAPIExprError(expr_info,
+                                "Alternate '%s' member '%s' cannot use "
+                                "type '%s'" % (name, key, value))
         if qtype in types_seen:
             raise QAPIExprError(expr_info,
                                 "Alternate '%s' member '%s' can't "
@@ -667,7 +663,6 @@ def check_enum(expr, expr_info):
     name = expr['enum']
     members = expr.get('data')
     prefix = expr.get('prefix')
-    values = {'MAX': '(automatic)'}
 
     if not isinstance(members, list):
         raise QAPIExprError(expr_info,
@@ -678,12 +673,6 @@ def check_enum(expr, expr_info):
     for member in members:
         check_name(expr_info, "Member of enum '%s'" % name, member,
                    enum_member=True)
-        key = camel_to_upper(member)
-        if key in values:
-            raise QAPIExprError(expr_info,
-                                "Enum '%s' member '%s' clashes with '%s'"
-                                % (name, member, values[key]))
-        values[key] = member
 
 
 def check_struct(expr, expr_info):
@@ -694,8 +683,6 @@ def check_struct(expr, expr_info):
                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_keys(expr_elem, meta, required, optional=[]):
@@ -715,6 +702,10 @@ def check_keys(expr_elem, meta, required, optional=[]):
             raise QAPIExprError(info,
                                 "'%s' of %s '%s' should only use false value"
                                 % (key, meta, name))
+        if key == 'boxed' and value is not True:
+            raise QAPIExprError(info,
+                                "'%s' of %s '%s' should only use true value"
+                                % (key, meta, name))
     for key in required:
         if key not in expr:
             raise QAPIExprError(info,
@@ -746,10 +737,10 @@ def check_exprs(exprs):
             add_struct(expr, info)
         elif 'command' in expr:
             check_keys(expr_elem, 'command', [],
-                       ['data', 'returns', 'gen', 'success-response'])
+                       ['data', 'returns', 'gen', 'success-response', 'boxed'])
             add_name(expr['command'], info, 'command')
         elif 'event' in expr:
-            check_keys(expr_elem, 'event', [], ['data'])
+            check_keys(expr_elem, 'event', [], ['data', 'boxed'])
             add_name(expr['event'], info, 'event')
         else:
             raise QAPIExprError(expr_elem['info'],
@@ -847,19 +838,26 @@ class QAPISchemaVisitor(object):
         pass
 
     def visit_command(self, name, info, arg_type, ret_type,
-                      gen, success_response):
+                      gen, success_response, boxed):
         pass
 
-    def visit_event(self, name, info, arg_type):
+    def visit_event(self, name, info, arg_type, boxed):
         pass
 
 
 class QAPISchemaType(QAPISchemaEntity):
-    def c_type(self, is_param=False):
-        return c_name(self.name) + pointer_suffix
+    # Return the C type for common use.
+    # For the types we commonly box, this is a pointer type.
+    def c_type(self):
+        pass
 
-    def c_null(self):
-        return 'NULL'
+    # Return the C type to be used in a parameter list.
+    def c_param_type(self):
+        return self.c_type()
+
+    # Return the C type to be used where we suppress boxing.
+    def c_unboxed_type(self):
+        return self.c_type()
 
     def json_type(self):
         pass
@@ -876,25 +874,24 @@ class QAPISchemaType(QAPISchemaEntity):
 
 
 class QAPISchemaBuiltinType(QAPISchemaType):
-    def __init__(self, name, json_type, c_type, c_null):
+    def __init__(self, name, json_type, c_type):
         QAPISchemaType.__init__(self, name, None)
         assert not c_type or isinstance(c_type, str)
         assert json_type in ('string', 'number', 'int', 'boolean', 'null',
                              'value')
         self._json_type_name = json_type
         self._c_type_name = c_type
-        self._c_null_val = c_null
 
     def c_name(self):
         return self.name
 
-    def c_type(self, is_param=False):
-        if is_param and self.name == 'str':
-            return 'const ' + self._c_type_name
+    def c_type(self):
         return self._c_type_name
 
-    def c_null(self):
-        return self._c_null_val
+    def c_param_type(self):
+        if self.name == 'str':
+            return 'const ' + self._c_type_name
+        return self._c_type_name
 
     def json_type(self):
         return self._json_type_name
@@ -907,31 +904,33 @@ class QAPISchemaEnumType(QAPISchemaType):
     def __init__(self, name, info, values, prefix):
         QAPISchemaType.__init__(self, name, info)
         for v in values:
-            assert isinstance(v, str)
+            assert isinstance(v, QAPISchemaMember)
+            v.set_owner(name)
         assert prefix is None or isinstance(prefix, str)
         self.values = values
         self.prefix = prefix
 
     def check(self, schema):
-        assert len(set(self.values)) == len(self.values)
+        seen = {}
+        for v in self.values:
+            v.check_clash(self.info, seen)
 
     def is_implicit(self):
         # See QAPISchema._make_implicit_enum_type()
         return self.name.endswith('Kind')
 
-    def c_type(self, is_param=False):
+    def c_type(self):
         return c_name(self.name)
 
-    def c_null(self):
-        return c_enum_const(self.name, (self.values + ['MAX'])[0],
-                            self.prefix)
+    def member_names(self):
+        return [v.name for v in self.values]
 
     def json_type(self):
         return 'string'
 
     def visit(self, visitor):
         visitor.visit_enum_type(self.name, self.info,
-                                self.values, self.prefix)
+                                self.member_names(), self.prefix)
 
 
 class QAPISchemaArrayType(QAPISchemaType):
@@ -948,6 +947,9 @@ class QAPISchemaArrayType(QAPISchemaType):
     def is_implicit(self):
         return True
 
+    def c_type(self):
+        return c_name(self.name) + pointer_suffix
+
     def json_type(self):
         return 'array'
 
@@ -964,8 +966,10 @@ class QAPISchemaObjectType(QAPISchemaType):
         assert base is None or isinstance(base, str)
         for m in local_members:
             assert isinstance(m, QAPISchemaObjectTypeMember)
-        assert (variants is None or
-                isinstance(variants, QAPISchemaObjectTypeVariants))
+            m.set_owner(name)
+        if variants is not None:
+            assert isinstance(variants, QAPISchemaObjectTypeVariants)
+            variants.set_owner(name)
         self._base_name = base
         self.base = None
         self.local_members = local_members
@@ -973,7 +977,9 @@ class QAPISchemaObjectType(QAPISchemaType):
         self.members = None
 
     def check(self, schema):
-        assert self.members is not False        # not running in cycles
+        if self.members is False:               # check for cycles
+            raise QAPIExprError(self.info,
+                                "Object %s contains itself" % self.name)
         if self.members:
             return
         self.members = False                    # mark as being checked
@@ -982,32 +988,43 @@ class QAPISchemaObjectType(QAPISchemaType):
             self.base = schema.lookup_type(self._base_name)
             assert isinstance(self.base, QAPISchemaObjectType)
             self.base.check(schema)
-            self.base.check_clash(schema, seen)
+            self.base.check_clash(schema, self.info, seen)
         for m in self.local_members:
             m.check(schema)
-            m.check_clash(seen)
+            m.check_clash(self.info, seen)
         self.members = seen.values()
         if self.variants:
             self.variants.check(schema, seen)
             assert self.variants.tag_member in self.members
-            self.variants.check_clash(schema, seen)
+            self.variants.check_clash(schema, self.info, seen)
 
-    def check_clash(self, schema, seen):
+    # Check that the members of this type do not cause duplicate JSON members,
+    # and update seen to track the members seen so far. Report any errors
+    # on behalf of info, which is not necessarily self.info
+    def check_clash(self, schema, info, seen):
         assert not self.variants       # not implemented
         for m in self.members:
-            m.check_clash(seen)
+            m.check_clash(info, seen)
 
     def is_implicit(self):
-        # See QAPISchema._make_implicit_object_type()
-        return self.name[0] == ':'
+        # See QAPISchema._make_implicit_object_type(), as well as
+        # _def_predefineds()
+        return self.name.startswith('q_')
+
+    def is_empty(self):
+        assert self.members is not None
+        return not self.members and not self.variants
 
     def c_name(self):
-        assert not self.is_implicit()
+        assert self.name != 'q_empty'
         return QAPISchemaType.c_name(self)
 
-    def c_type(self, is_param=False):
+    def c_type(self):
         assert not self.is_implicit()
-        return QAPISchemaType.c_type(self)
+        return c_name(self.name) + pointer_suffix
+
+    def c_unboxed_type(self):
+        return c_name(self.name)
 
     def json_type(self):
         return 'object'
@@ -1019,25 +1036,66 @@ class QAPISchemaObjectType(QAPISchemaType):
                                        self.members, self.variants)
 
 
-class QAPISchemaObjectTypeMember(object):
-    def __init__(self, name, typ, optional):
+class QAPISchemaMember(object):
+    role = 'member'
+
+    def __init__(self, name):
         assert isinstance(name, str)
+        self.name = name
+        self.owner = None
+
+    def set_owner(self, name):
+        assert not self.owner
+        self.owner = name
+
+    def check_clash(self, info, seen):
+        cname = c_name(self.name)
+        if cname.lower() != cname and self.owner not in case_whitelist:
+            raise QAPIExprError(info,
+                                "%s should not use uppercase" % self.describe())
+        if cname in seen:
+            raise QAPIExprError(info,
+                                "%s collides with %s"
+                                % (self.describe(), seen[cname].describe()))
+        seen[cname] = self
+
+    def _pretty_owner(self):
+        owner = self.owner
+        if owner.startswith('q_obj_'):
+            # See QAPISchema._make_implicit_object_type() - reverse the
+            # mapping there to create a nice human-readable description
+            owner = owner[6:]
+            if owner.endswith('-arg'):
+                return '(parameter of %s)' % owner[:-4]
+            elif owner.endswith('-base'):
+                return '(base of %s)' % owner[:-5]
+            else:
+                assert owner.endswith('-wrapper')
+                # Unreachable and not implemented
+                assert False
+        if owner.endswith('Kind'):
+            # See QAPISchema._make_implicit_enum_type()
+            return '(branch of %s)' % owner[:-4]
+        return '(%s of %s)' % (self.role, owner)
+
+    def describe(self):
+        return "'%s' %s" % (self.name, self._pretty_owner())
+
+
+class QAPISchemaObjectTypeMember(QAPISchemaMember):
+    def __init__(self, name, typ, optional):
+        QAPISchemaMember.__init__(self, name)
         assert isinstance(typ, str)
         assert isinstance(optional, bool)
-        self.name = name
         self._type_name = typ
         self.type = None
         self.optional = optional
 
     def check(self, schema):
+        assert self.owner
         self.type = schema.lookup_type(self._type_name)
         assert self.type
 
-    def check_clash(self, seen):
-        # TODO change key of seen from QAPI name to C name
-        assert self.name not in seen
-        seen[self.name] = self
-
 
 class QAPISchemaObjectTypeVariants(object):
     def __init__(self, tag_name, tag_member, variants):
@@ -1048,53 +1106,53 @@ class QAPISchemaObjectTypeVariants(object):
         assert bool(tag_member) != bool(tag_name)
         assert (isinstance(tag_name, str) or
                 isinstance(tag_member, QAPISchemaObjectTypeMember))
+        assert len(variants) > 0
         for v in variants:
             assert isinstance(v, QAPISchemaObjectTypeVariant)
-        self.tag_name = tag_name
+        self._tag_name = tag_name
         self.tag_member = tag_member
         self.variants = variants
 
+    def set_owner(self, name):
+        for v in self.variants:
+            v.set_owner(name)
+
     def check(self, schema, seen):
         if not self.tag_member:    # flat union
-            self.tag_member = seen[self.tag_name]
+            self.tag_member = seen[c_name(self._tag_name)]
+            assert self._tag_name == self.tag_member.name
         assert isinstance(self.tag_member.type, QAPISchemaEnumType)
         for v in self.variants:
-            v.check(schema, self.tag_member.type)
-            if isinstance(v.type, QAPISchemaObjectType):
+            v.check(schema)
+            # Union names must match enum values; alternate names are
+            # checked separately. Use 'seen' to tell the two apart.
+            if seen:
+                assert v.name in self.tag_member.type.member_names()
+                assert isinstance(v.type, QAPISchemaObjectType)
                 v.type.check(schema)
 
-    def check_clash(self, schema, seen):
+    def check_clash(self, schema, info, seen):
         for v in self.variants:
             # Reset seen map for each variant, since qapi names from one
             # branch do not affect another branch
             assert isinstance(v.type, QAPISchemaObjectType)
-            v.type.check_clash(schema, dict(seen))
+            v.type.check_clash(schema, info, dict(seen))
 
 
 class QAPISchemaObjectTypeVariant(QAPISchemaObjectTypeMember):
+    role = 'branch'
+
     def __init__(self, name, typ):
         QAPISchemaObjectTypeMember.__init__(self, name, typ, False)
 
-    def check(self, schema, tag_type):
-        QAPISchemaObjectTypeMember.check(self, schema)
-        assert self.name in tag_type.values
-
-    # This function exists to support ugly simple union special cases
-    # TODO get rid of them, and drop the function
-    def simple_union_type(self):
-        if (self.type.is_implicit() and
-                isinstance(self.type, QAPISchemaObjectType)):
-            assert len(self.type.members) == 1
-            assert not self.type.variants
-            return self.type.members[0].type
-        return None
-
 
 class QAPISchemaAlternateType(QAPISchemaType):
     def __init__(self, name, info, variants):
         QAPISchemaType.__init__(self, name, info)
         assert isinstance(variants, QAPISchemaObjectTypeVariants)
-        assert not variants.tag_name
+        assert variants.tag_member
+        variants.set_owner(name)
+        variants.tag_member.set_owner(self.name)
         self.variants = variants
 
     def check(self, schema):
@@ -1102,6 +1160,14 @@ class QAPISchemaAlternateType(QAPISchemaType):
         # Not calling self.variants.check_clash(), because there's nothing
         # to clash with
         self.variants.check(schema, {})
+        # Alternate branch names have no relation to the tag enum values;
+        # so we have to check for potential name collisions ourselves.
+        seen = {}
+        for v in self.variants.variants:
+            v.check_clash(self.info, seen)
+
+    def c_type(self):
+        return c_name(self.name) + pointer_suffix
 
     def json_type(self):
         return 'value'
@@ -1109,9 +1175,13 @@ class QAPISchemaAlternateType(QAPISchemaType):
     def visit(self, visitor):
         visitor.visit_alternate_type(self.name, self.info, self.variants)
 
+    def is_empty(self):
+        return False
+
 
 class QAPISchemaCommand(QAPISchemaEntity):
-    def __init__(self, name, info, arg_type, ret_type, gen, success_response):
+    def __init__(self, name, info, arg_type, ret_type, gen, success_response,
+                 boxed):
         QAPISchemaEntity.__init__(self, name, info)
         assert not arg_type or isinstance(arg_type, str)
         assert not ret_type or isinstance(ret_type, str)
@@ -1121,12 +1191,24 @@ class QAPISchemaCommand(QAPISchemaEntity):
         self.ret_type = None
         self.gen = gen
         self.success_response = success_response
+        self.boxed = boxed
 
     def check(self, schema):
         if self._arg_type_name:
             self.arg_type = schema.lookup_type(self._arg_type_name)
-            assert isinstance(self.arg_type, QAPISchemaObjectType)
-            assert not self.arg_type.variants   # not implemented
+            assert (isinstance(self.arg_type, QAPISchemaObjectType) or
+                    isinstance(self.arg_type, QAPISchemaAlternateType))
+            self.arg_type.check(schema)
+            if self.boxed:
+                if self.arg_type.is_empty():
+                    raise QAPIExprError(self.info,
+                                        "Cannot use 'boxed' with empty type")
+            else:
+                assert not isinstance(self.arg_type, QAPISchemaAlternateType)
+                assert not self.arg_type.variants
+        elif self.boxed:
+            raise QAPIExprError(self.info,
+                                "Use of 'boxed' requires 'data'")
         if self._ret_type_name:
             self.ret_type = schema.lookup_type(self._ret_type_name)
             assert isinstance(self.ret_type, QAPISchemaType)
@@ -1134,24 +1216,36 @@ class QAPISchemaCommand(QAPISchemaEntity):
     def visit(self, visitor):
         visitor.visit_command(self.name, self.info,
                               self.arg_type, self.ret_type,
-                              self.gen, self.success_response)
+                              self.gen, self.success_response, self.boxed)
 
 
 class QAPISchemaEvent(QAPISchemaEntity):
-    def __init__(self, name, info, arg_type):
+    def __init__(self, name, info, arg_type, boxed):
         QAPISchemaEntity.__init__(self, name, info)
         assert not arg_type or isinstance(arg_type, str)
         self._arg_type_name = arg_type
         self.arg_type = None
+        self.boxed = boxed
 
     def check(self, schema):
         if self._arg_type_name:
             self.arg_type = schema.lookup_type(self._arg_type_name)
-            assert isinstance(self.arg_type, QAPISchemaObjectType)
-            assert not self.arg_type.variants   # not implemented
+            assert (isinstance(self.arg_type, QAPISchemaObjectType) or
+                    isinstance(self.arg_type, QAPISchemaAlternateType))
+            self.arg_type.check(schema)
+            if self.boxed:
+                if self.arg_type.is_empty():
+                    raise QAPIExprError(self.info,
+                                        "Cannot use 'boxed' with empty type")
+            else:
+                assert not isinstance(self.arg_type, QAPISchemaAlternateType)
+                assert not self.arg_type.variants
+        elif self.boxed:
+            raise QAPIExprError(self.info,
+                                "Use of 'boxed' requires 'data'")
 
     def visit(self, visitor):
-        visitor.visit_event(self.name, self.info, self.arg_type)
+        visitor.visit_event(self.name, self.info, self.arg_type, self.boxed)
 
 
 class QAPISchema(object):
@@ -1164,7 +1258,7 @@ class QAPISchema(object):
             self._predefining = False
             self._def_exprs()
             self.check()
-        except (QAPISchemaError, QAPIExprError), err:
+        except (QAPISchemaError, QAPIExprError) as err:
             print >>sys.stderr, err
             exit(1)
 
@@ -1183,9 +1277,8 @@ class QAPISchema(object):
     def lookup_type(self, name):
         return self.lookup_entity(name, QAPISchemaType)
 
-    def _def_builtin_type(self, name, json_type, c_type, c_null):
-        self._def_entity(QAPISchemaBuiltinType(name, json_type,
-                                               c_type, c_null))
+    def _def_builtin_type(self, name, json_type, c_type):
+        self._def_entity(QAPISchemaBuiltinType(name, json_type, c_type))
         # TODO As long as we have QAPI_TYPES_BUILTIN to share multiple
         # qapi-types.h from a single .c, all arrays of builtins must be
         # declared in the first file whether or not they are used.  Nicer
@@ -1194,28 +1287,38 @@ class QAPISchema(object):
         self._make_array_type(name, None)
 
     def _def_predefineds(self):
-        for t in [('str',    'string',  'char' + pointer_suffix, 'NULL'),
-                  ('number', 'number',  'double',   '0'),
-                  ('int',    'int',     'int64_t',  '0'),
-                  ('int8',   'int',     'int8_t',   '0'),
-                  ('int16',  'int',     'int16_t',  '0'),
-                  ('int32',  'int',     'int32_t',  '0'),
-                  ('int64',  'int',     'int64_t',  '0'),
-                  ('uint8',  'int',     'uint8_t',  '0'),
-                  ('uint16', 'int',     'uint16_t', '0'),
-                  ('uint32', 'int',     'uint32_t', '0'),
-                  ('uint64', 'int',     'uint64_t', '0'),
-                  ('size',   'int',     'uint64_t', '0'),
-                  ('bool',   'boolean', 'bool',     'false'),
-                  ('any',    'value',   'QObject' + pointer_suffix, 'NULL')]:
+        for t in [('str',    'string',  'char' + pointer_suffix),
+                  ('number', 'number',  'double'),
+                  ('int',    'int',     'int64_t'),
+                  ('int8',   'int',     'int8_t'),
+                  ('int16',  'int',     'int16_t'),
+                  ('int32',  'int',     'int32_t'),
+                  ('int64',  'int',     'int64_t'),
+                  ('uint8',  'int',     'uint8_t'),
+                  ('uint16', 'int',     'uint16_t'),
+                  ('uint32', 'int',     'uint32_t'),
+                  ('uint64', 'int',     'uint64_t'),
+                  ('size',   'int',     'uint64_t'),
+                  ('bool',   'boolean', 'bool'),
+                  ('any',    'value',   'QObject' + pointer_suffix)]:
             self._def_builtin_type(*t)
-        self.the_empty_object_type = QAPISchemaObjectType(':empty', None, None,
-                                                          [], None)
+        self.the_empty_object_type = QAPISchemaObjectType('q_empty', None,
+                                                          None, [], None)
         self._def_entity(self.the_empty_object_type)
+        qtype_values = self._make_enum_members(['none', 'qnull', 'qint',
+                                                'qstring', 'qdict', 'qlist',
+                                                'qfloat', 'qbool'])
+        self._def_entity(QAPISchemaEnumType('QType', None, qtype_values,
+                                            'QTYPE'))
+
+    def _make_enum_members(self, values):
+        return [QAPISchemaMember(v) for v in values]
 
     def _make_implicit_enum_type(self, name, info, values):
+        # See also QAPISchemaObjectTypeMember._pretty_owner()
         name = name + 'Kind'   # Use namespace reserved by add_name()
-        self._def_entity(QAPISchemaEnumType(name, info, values, None))
+        self._def_entity(QAPISchemaEnumType(
+            name, info, self._make_enum_members(values), None))
         return name
 
     def _make_array_type(self, element_type, info):
@@ -1227,7 +1330,8 @@ class QAPISchema(object):
     def _make_implicit_object_type(self, name, info, role, members):
         if not members:
             return None
-        name = ':obj-%s-%s' % (name, role)
+        # See also QAPISchemaObjectTypeMember._pretty_owner()
+        name = 'q_obj_%s-%s' % (name, role)
         if not self.lookup_entity(name, QAPISchemaObjectType):
             self._def_entity(QAPISchemaObjectType(name, info, None,
                                                   members, None))
@@ -1237,7 +1341,8 @@ class QAPISchema(object):
         name = expr['enum']
         data = expr['data']
         prefix = expr.get('prefix')
-        self._def_entity(QAPISchemaEnumType(name, info, data, prefix))
+        self._def_entity(QAPISchemaEnumType(
+            name, info, self._make_enum_members(data), prefix))
 
     def _make_member(self, name, typ, info):
         optional = False
@@ -1272,17 +1377,15 @@ class QAPISchema(object):
             typ, info, 'wrapper', [self._make_member('data', typ, info)])
         return QAPISchemaObjectTypeVariant(case, typ)
 
-    def _make_implicit_tag(self, type_name, info, variants):
-        typ = self._make_implicit_enum_type(type_name, info,
-                                            [v.name for v in variants])
-        return QAPISchemaObjectTypeMember('type', typ, False)
-
     def _def_union_type(self, expr, info):
         name = expr['union']
         data = expr['data']
         base = expr.get('base')
         tag_name = expr.get('discriminator')
         tag_member = None
+        if isinstance(base, dict):
+            base = (self._make_implicit_object_type(
+                    name, info, 'base', self._make_members(base, info)))
         if tag_name:
             variants = [self._make_variant(key, value)
                         for (key, value) in data.iteritems()]
@@ -1290,7 +1393,9 @@ class QAPISchema(object):
         else:
             variants = [self._make_simple_variant(key, value, info)
                         for (key, value) in data.iteritems()]
-            tag_member = self._make_implicit_tag(name, info, variants)
+            typ = self._make_implicit_enum_type(name, info,
+                                                [v.name for v in variants])
+            tag_member = QAPISchemaObjectTypeMember('type', typ, False)
             members = [tag_member]
         self._def_entity(
             QAPISchemaObjectType(name, info, base, members,
@@ -1303,7 +1408,7 @@ class QAPISchema(object):
         data = expr['data']
         variants = [self._make_variant(key, value)
                     for (key, value) in data.iteritems()]
-        tag_member = self._make_implicit_tag(name, info, variants)
+        tag_member = QAPISchemaObjectTypeMember('type', 'QType', False)
         self._def_entity(
             QAPISchemaAlternateType(name, info,
                                     QAPISchemaObjectTypeVariants(None,
@@ -1316,6 +1421,7 @@ class QAPISchema(object):
         rets = expr.get('returns')
         gen = expr.get('gen', True)
         success_response = expr.get('success-response', True)
+        boxed = expr.get('boxed', False)
         if isinstance(data, OrderedDict):
             data = self._make_implicit_object_type(
                 name, info, 'arg', self._make_members(data, info))
@@ -1323,15 +1429,16 @@ class QAPISchema(object):
             assert len(rets) == 1
             rets = self._make_array_type(rets[0], info)
         self._def_entity(QAPISchemaCommand(name, info, data, rets, gen,
-                                           success_response))
+                                           success_response, boxed))
 
     def _def_event(self, expr, info):
         name = expr['event']
         data = expr.get('data')
+        boxed = expr.get('boxed', False)
         if isinstance(data, OrderedDict):
             data = self._make_implicit_object_type(
                 name, info, 'arg', self._make_members(data, info))
-        self._def_entity(QAPISchemaEvent(name, info, data))
+        self._def_entity(QAPISchemaEvent(name, info, data, boxed))
 
     def _def_exprs(self):
         for expr_elem in self.exprs:
@@ -1407,7 +1514,7 @@ def camel_to_upper(value):
 def c_enum_const(type_name, const_name, prefix=None):
     if prefix is not None:
         type_name = prefix
-    return camel_to_upper(type_name + '_' + const_name)
+    return camel_to_upper(type_name) + '_' + c_name(const_name, False).upper()
 
 c_name_trans = string.maketrans('.-', '__')
 
@@ -1448,11 +1555,12 @@ def c_name(name, protect=True):
                      'and', 'and_eq', 'bitand', 'bitor', 'compl', 'not',
                      'not_eq', 'or', 'or_eq', 'xor', 'xor_eq'])
     # namespace pollution:
-    polluted_words = set(['unix', 'errno'])
+    polluted_words = set(['unix', 'errno', 'mips', 'sparc'])
+    name = name.translate(c_name_trans)
     if protect and (name in c89_words | c99_words | c11_words | gcc_words
                     | cpp_words | polluted_words):
         return "q_" + name
-    return name.translate(c_name_trans)
+    return name
 
 eatspace = '\033EATSPACE.'
 pointer_suffix = ' *' + eatspace
@@ -1532,7 +1640,7 @@ const char *const %(c_name)s_lookup[] = {
 ''',
                      index=index, value=value)
 
-    max_index = c_enum_const(name, 'MAX', prefix)
+    max_index = c_enum_const(name, '_MAX', prefix)
     ret += mcgen('''
     [%(max_index)s] = NULL,
 };
@@ -1543,7 +1651,7 @@ const char *const %(c_name)s_lookup[] = {
 
 def gen_enum(name, values, prefix=None):
     # append automatically generated _MAX value
-    enum_values = values + ['MAX']
+    enum_values = values + ['_MAX']
 
     ret = mcgen('''
 
@@ -1573,77 +1681,29 @@ extern const char *const %(c_name)s_lookup[];
     return ret
 
 
-def gen_params(arg_type, extra):
+def gen_params(arg_type, boxed, extra):
     if not arg_type:
+        assert not boxed
         return extra
-    assert not arg_type.variants
     ret = ''
     sep = ''
-    for memb in arg_type.members:
-        ret += sep
+    if boxed:
+        ret += '%s arg' % arg_type.c_param_type()
         sep = ', '
-        if memb.optional:
-            ret += 'bool has_%s, ' % c_name(memb.name)
-        ret += '%s %s' % (memb.type.c_type(is_param=True), c_name(memb.name))
+    else:
+        assert not arg_type.variants
+        for memb in arg_type.members:
+            ret += sep
+            sep = ', '
+            if memb.optional:
+                ret += 'bool has_%s, ' % c_name(memb.name)
+            ret += '%s %s' % (memb.type.c_param_type(),
+                              c_name(memb.name))
     if extra:
         ret += sep + extra
     return ret
 
 
-def gen_err_check(label='out', skiperr=False):
-    if skiperr:
-        return ''
-    return mcgen('''
-    if (err) {
-        goto %(label)s;
-    }
-''',
-                 label=label)
-
-
-def gen_visit_fields(members, prefix='', need_cast=False, skiperr=False):
-    ret = ''
-    if skiperr:
-        errparg = 'NULL'
-    else:
-        errparg = '&err'
-
-    for memb in members:
-        if memb.optional:
-            ret += mcgen('''
-    visit_optional(v, &%(prefix)shas_%(c_name)s, "%(name)s", %(errp)s);
-''',
-                         prefix=prefix, c_name=c_name(memb.name),
-                         name=memb.name, errp=errparg)
-            ret += gen_err_check(skiperr=skiperr)
-            ret += mcgen('''
-    if (%(prefix)shas_%(c_name)s) {
-''',
-                         prefix=prefix, c_name=c_name(memb.name))
-            push_indent()
-
-        # Ugly: sometimes we need to cast away const
-        if need_cast and memb.type.name == 'str':
-            cast = '(char **)'
-        else:
-            cast = ''
-
-        ret += mcgen('''
-    visit_type_%(c_type)s(v, %(cast)s&%(prefix)s%(c_name)s, "%(name)s", %(errp)s);
-''',
-                     c_type=memb.type.c_name(), prefix=prefix, cast=cast,
-                     c_name=c_name(memb.name), name=memb.name,
-                     errp=errparg)
-        ret += gen_err_check(skiperr=skiperr)
-
-        if memb.optional:
-            pop_indent()
-            ret += mcgen('''
-    }
-''')
-    return ret
-
-
 #
 # Common command line parsing
 #
@@ -1656,7 +1716,7 @@ def parse_command_line(extra_options="", extra_long_options=[]):
                                        "chp:o:" + extra_options,
                                        ["source", "header", "prefix=",
                                         "output-dir="] + extra_long_options)
-    except getopt.GetoptError, err:
+    except getopt.GetoptError as err:
         print >>sys.stderr, "%s: %s" % (sys.argv[0], str(err))
         sys.exit(1)
 
@@ -1710,7 +1770,7 @@ def open_output(output_dir, do_c, do_h, prefix, c_file, h_file,
     if output_dir:
         try:
             os.makedirs(output_dir)
-        except os.error, e:
+        except os.error as e:
             if e.errno != errno.EEXIST:
                 raise