# Copyright 2013 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
# This module's classes provide an interface to mojo modules. Modules are
# collections of interfaces and structs to be used by mojo ipc clients and
# servers.
#
# A simple interface would be created this way:
# module = mojom.generate.module.Module('Foo')
# interface = module.AddInterface('Bar')
# method = interface.AddMethod('Tat', 0)
# method.AddParameter('baz', 0, mojom.INT32)
# We use our own version of __repr__ when displaying the AST, as the
# AST currently doesn't capture which nodes are reference (e.g. to
# types) and which nodes are definitions. This allows us to e.g. print
# the definition of a struct when it's defined inside a module, but
# only print its name when it's referenced in e.g. a method parameter.
def Repr(obj, as_ref=True):
"""A version of __repr__ that can distinguish references.
Sometimes we like to print an object's full representation
(e.g. with its fields) and sometimes we just want to reference an
object that was printed in full elsewhere. This function allows us
to make that distinction.
Args:
obj: The object whose string representation we compute.
as_ref: If True, use the short reference representation.
Returns:
A str representation of |obj|.
"""
if hasattr(obj, 'Repr'):
return obj.Repr(as_ref=as_ref)
# Since we cannot implement Repr for existing container types, we
# handle them here.
elif isinstance(obj, list):
if not obj:
return '[]'
else:
return ('[\n%s\n]' % (',\n'.join(' %s' % Repr(elem, as_ref).replace(
'\n', '\n ') for elem in obj)))
elif isinstance(obj, dict):
if not obj:
return '{}'
else:
return ('{\n%s\n}' % (',\n'.join(' %s: %s' % (
Repr(key, as_ref).replace('\n', '\n '),
Repr(val, as_ref).replace('\n', '\n '))
for key, val in obj.iteritems())))
else:
return repr(obj)
def GenericRepr(obj, names):
"""Compute generic Repr for |obj| based on the attributes in |names|.
Args:
obj: The object to compute a Repr for.
names: A dict from attribute names to include, to booleans
specifying whether those attributes should be shown as
references or not.
Returns:
A str representation of |obj|.
"""
def ReprIndent(name, as_ref):
return ' %s=%s' % (name, Repr(getattr(obj, name), as_ref).replace(
'\n', '\n '))
return '%s(\n%s\n)' % (
obj.__class__.__name__,
',\n'.join(ReprIndent(name, as_ref)
for (name, as_ref) in names.iteritems()))
class Kind(object):
"""Kind represents a type (e.g. int8, string).
Attributes:
spec: A string uniquely identifying the type. May be None.
parent_kind: The enclosing type. For example, a struct defined
inside an interface has that interface as its parent. May be None.
"""
def __init__(self, spec=None):
self.spec = spec
self.parent_kind = None
def Repr(self, as_ref=True):
return '<%s spec=%r>' % (self.__class__.__name__, self.spec)
def __repr__(self):
# Gives us a decent __repr__ for all kinds.
return self.Repr()
class ReferenceKind(Kind):
"""ReferenceKind represents pointer and handle types.
A type is nullable if null (for pointer types) or invalid handle (for handle
types) is a legal value for the type.
Attributes:
is_nullable: True if the type is nullable.
"""
def __init__(self, spec=None, is_nullable=False):
assert spec is None or is_nullable == spec.startswith('?')
Kind.__init__(self, spec)
self.is_nullable = is_nullable
self.shared_definition = {}
def Repr(self, as_ref=True):
return '<%s spec=%r is_nullable=%r>' % (self.__class__.__name__, self.spec,
self.is_nullable)
def MakeNullableKind(self):
assert not self.is_nullable
if self == STRING:
return NULLABLE_STRING
if self == HANDLE:
return NULLABLE_HANDLE
if self == DCPIPE:
return NULLABLE_DCPIPE
if self == DPPIPE:
return NULLABLE_DPPIPE
if self == MSGPIPE:
return NULLABLE_MSGPIPE
if self == SHAREDBUFFER:
return NULLABLE_SHAREDBUFFER
nullable_kind = type(self)()
nullable_kind.shared_definition = self.shared_definition
if self.spec is not None:
nullable_kind.spec = '?' + self.spec
nullable_kind.is_nullable = True
return nullable_kind
@classmethod
def AddSharedProperty(cls, name):
"""Adds a property |name| to |cls|, which accesses the corresponding item in
|shared_definition|.
The reason of adding such indirection is to enable sharing definition
between a reference kind and its nullable variation. For example:
a = Struct('test_struct_1')
b = a.MakeNullableKind()
a.name = 'test_struct_2'
print b.name # Outputs 'test_struct_2'.
"""
def Get(self):
return self.shared_definition[name]
def Set(self, value):
self.shared_definition[name] = value
setattr(cls, name, property(Get, Set))
# Initialize the set of primitive types. These can be accessed by clients.
BOOL = Kind('b')
INT8 = Kind('i8')
INT16 = Kind('i16')
INT32 = Kind('i32')
INT64 = Kind('i64')
UINT8 = Kind('u8')
UINT16 = Kind('u16')
UINT32 = Kind('u32')
UINT64 = Kind('u64')
FLOAT = Kind('f')
DOUBLE = Kind('d')
STRING = ReferenceKind('s')
HANDLE = ReferenceKind('h')
DCPIPE = ReferenceKind('h:d:c')
DPPIPE = ReferenceKind('h:d:p')
MSGPIPE = ReferenceKind('h:m')
SHAREDBUFFER = ReferenceKind('h:s')
NULLABLE_STRING = ReferenceKind('?s', True)
NULLABLE_HANDLE = ReferenceKind('?h', True)
NULLABLE_DCPIPE = ReferenceKind('?h:d:c', True)
NULLABLE_DPPIPE = ReferenceKind('?h:d:p', True)
NULLABLE_MSGPIPE = ReferenceKind('?h:m', True)
NULLABLE_SHAREDBUFFER = ReferenceKind('?h:s', True)
# Collection of all Primitive types
PRIMITIVES = (
BOOL,
INT8,
INT16,
INT32,
INT64,
UINT8,
UINT16,
UINT32,
UINT64,
FLOAT,
DOUBLE,
STRING,
HANDLE,
DCPIPE,
DPPIPE,
MSGPIPE,
SHAREDBUFFER,
NULLABLE_STRING,
NULLABLE_HANDLE,
NULLABLE_DCPIPE,
NULLABLE_DPPIPE,
NULLABLE_MSGPIPE,
NULLABLE_SHAREDBUFFER
)
ATTRIBUTE_MIN_VERSION = 'MinVersion'
ATTRIBUTE_EXTENSIBLE = 'Extensible'
ATTRIBUTE_SYNC = 'Sync'
class NamedValue(object):
def __init__(self, module, parent_kind, name):
self.module = module
self.namespace = module.namespace
self.parent_kind = parent_kind
self.name = name
self.imported_from = None
def GetSpec(self):
return (self.namespace + '.' +
(self.parent_kind and (self.parent_kind.name + '.') or "") +
self.name)
class BuiltinValue(object):
def __init__(self, value):
self.value = value
class ConstantValue(NamedValue):
def __init__(self, module, parent_kind, constant):
NamedValue.__init__(self, module, parent_kind, constant.name)
self.constant = constant
class EnumValue(NamedValue):
def __init__(self, module, enum, field):
NamedValue.__init__(self, module, enum.parent_kind, field.name)
self.enum = enum
def GetSpec(self):
return (self.namespace + '.' +
(self.parent_kind and (self.parent_kind.name + '.') or "") +
self.enum.name + '.' + self.name)
class Constant(object):
def __init__(self, name=None, kind=None, value=None, parent_kind=None):
self.name = name
self.kind = kind
self.value = value
self.parent_kind = parent_kind
class Field(object):
def __init__(self, name=None, kind=None, ordinal=None, default=None,
attributes=None):
if self.__class__.__name__ == 'Field':
raise Exception()
self.name = name
self.kind = kind
self.ordinal = ordinal
self.default = default
self.attributes = attributes
def Repr(self, as_ref=True):
# Fields are only referenced by objects which define them and thus
# they are always displayed as non-references.
return GenericRepr(self, {'name': False, 'kind': True})
@property
def min_version(self):
return self.attributes.get(ATTRIBUTE_MIN_VERSION) \
if self.attributes else None
class StructField(Field): pass
class UnionField(Field): pass
class Struct(ReferenceKind):
"""A struct with typed fields.
Attributes:
name: {str} The name of the struct type.
native_only: {bool} Does the struct have a body (i.e. any fields) or is it
purely a native struct.
module: {Module} The defining module.
imported_from: {dict} Information about where this union was
imported from.
fields: {List[StructField]} The members of the struct.
attributes: {dict} Additional information about the struct, such as
if it's a native struct.
"""
ReferenceKind.AddSharedProperty('name')
ReferenceKind.AddSharedProperty('native_only')
ReferenceKind.AddSharedProperty('module')
ReferenceKind.AddSharedProperty('imported_from')
ReferenceKind.AddSharedProperty('fields')
ReferenceKind.AddSharedProperty('attributes')
def __init__(self, name=None, module=None, attributes=None):
if name is not None:
spec = 'x:' + name
else:
spec = None
ReferenceKind.__init__(self, spec)
self.name = name
self.native_only = False
self.module = module
self.imported_from = None
self.fields = []
self.attributes = attributes
def Repr(self, as_ref=True):
if as_ref:
return '<%s name=%r imported_from=%s>' % (
self.__class__.__name__, self.name,
Repr(self.imported_from, as_ref=True))
else:
return GenericRepr(self, {'name': False, 'fields': False,
'imported_from': True})
def AddField(self, name, kind, ordinal=None, default=None, attributes=None):
field = StructField(name, kind, ordinal, default, attributes)
self.fields.append(field)
return field
class Union(ReferenceKind):
"""A union of several kinds.
Attributes:
name: {str} The name of the union type.
module: {Module} The defining module.
imported_from: {dict} Information about where this union was
imported from.
fields: {List[UnionField]} The members of the union.
attributes: {dict} Additional information about the union, such as
which Java class name to use to represent it in the generated
bindings.
"""
ReferenceKind.AddSharedProperty('name')
ReferenceKind.AddSharedProperty('module')
ReferenceKind.AddSharedProperty('imported_from')
ReferenceKind.AddSharedProperty('fields')
ReferenceKind.AddSharedProperty('attributes')
def __init__(self, name=None, module=None, attributes=None):
if name is not None:
spec = 'x:' + name
else:
spec = None
ReferenceKind.__init__(self, spec)
self.name = name
self.module = module
self.imported_from = None
self.fields = []
self.attributes = attributes
def Repr(self, as_ref=True):
if as_ref:
return '<%s spec=%r is_nullable=%r fields=%s>' % (
self.__class__.__name__, self.spec, self.is_nullable,
Repr(self.fields))
else:
return GenericRepr(self, {'fields': True, 'is_nullable': False})
def AddField(self, name, kind, ordinal=None, attributes=None):
field = UnionField(name, kind, ordinal, None, attributes)
self.fields.append(field)
return field
class Array(ReferenceKind):
"""An array.
Attributes:
kind: {Kind} The type of the elements. May be None.
length: The number of elements. None if unknown.
"""
ReferenceKind.AddSharedProperty('kind')
ReferenceKind.AddSharedProperty('length')
def __init__(self, kind=None, length=None):
if kind is not None:
if length is not None:
spec = 'a%d:%s' % (length, kind.spec)
else:
spec = 'a:%s' % kind.spec
ReferenceKind.__init__(self, spec)
else:
ReferenceKind.__init__(self)
self.kind = kind
self.length = length
def Repr(self, as_ref=True):
if as_ref:
return '<%s spec=%r is_nullable=%r kind=%s length=%r>' % (
self.__class__.__name__, self.spec, self.is_nullable, Repr(self.kind),
self.length)
else:
return GenericRepr(self, {'kind': True, 'length': False,
'is_nullable': False})
class Map(ReferenceKind):
"""A map.
Attributes:
key_kind: {Kind} The type of the keys. May be None.
value_kind: {Kind} The type of the elements. May be None.
"""
ReferenceKind.AddSharedProperty('key_kind')
ReferenceKind.AddSharedProperty('value_kind')
def __init__(self, key_kind=None, value_kind=None):
if (key_kind is not None and value_kind is not None):
ReferenceKind.__init__(self,
'm[' + key_kind.spec + '][' + value_kind.spec +
']')
if IsNullableKind(key_kind):
raise Exception("Nullable kinds cannot be keys in maps.")
if IsAnyHandleKind(key_kind):
raise Exception("Handles cannot be keys in maps.")
if IsAnyInterfaceKind(key_kind):
raise Exception("Interfaces cannot be keys in maps.")
if IsArrayKind(key_kind):
raise Exception("Arrays cannot be keys in maps.")
else:
ReferenceKind.__init__(self)
self.key_kind = key_kind
self.value_kind = value_kind
def Repr(self, as_ref=True):
if as_ref:
return '<%s spec=%r is_nullable=%r key_kind=%s value_kind=%s>' % (
self.__class__.__name__, self.spec, self.is_nullable,
Repr(self.key_kind), Repr(self.value_kind))
else:
return GenericRepr(self, {'key_kind': True, 'value_kind': True})
class InterfaceRequest(ReferenceKind):
ReferenceKind.AddSharedProperty('kind')
def __init__(self, kind=None):
if kind is not None:
if not isinstance(kind, Interface):
raise Exception(
"Interface request requires %r to be an interface." % kind.spec)
ReferenceKind.__init__(self, 'r:' + kind.spec)
else:
ReferenceKind.__init__(self)
self.kind = kind
class AssociatedInterfaceRequest(ReferenceKind):
ReferenceKind.AddSharedProperty('kind')
def __init__(self, kind=None):
if kind is not None:
if not isinstance(kind, InterfaceRequest):
raise Exception(
"Associated interface request requires %r to be an interface "
"request." % kind.spec)
assert not kind.is_nullable
ReferenceKind.__init__(self, 'asso:' + kind.spec)
else:
ReferenceKind.__init__(self)
self.kind = kind.kind if kind is not None else None
class Parameter(object):
def __init__(self, name=None, kind=None, ordinal=None, default=None,
attributes=None):
self.name = name
self.ordinal = ordinal
self.kind = kind
self.default = default
self.attributes = attributes
def Repr(self, as_ref=True):
return '<%s name=%r kind=%s>' % (self.__class__.__name__, self.name,
self.kind.Repr(as_ref=True))
@property
def min_version(self):
return self.attributes.get(ATTRIBUTE_MIN_VERSION) \
if self.attributes else None
class Method(object):
def __init__(self, interface, name, ordinal=None, attributes=None):
self.interface = interface
self.name = name
self.ordinal = ordinal
self.parameters = []
self.response_parameters = None
self.attributes = attributes
def Repr(self, as_ref=True):
if as_ref:
return '<%s name=%r>' % (self.__class__.__name__, self.name)
else:
return GenericRepr(self, {'name': False, 'parameters': True,
'response_parameters': True})
def AddParameter(self, name, kind, ordinal=None, default=None,
attributes=None):
parameter = Parameter(name, kind, ordinal, default, attributes)
self.parameters.append(parameter)
return parameter
def AddResponseParameter(self, name, kind, ordinal=None, default=None,
attributes=None):
if self.response_parameters == None:
self.response_parameters = []
parameter = Parameter(name, kind, ordinal, default, attributes)
self.response_parameters.append(parameter)
return parameter
@property
def min_version(self):
return self.attributes.get(ATTRIBUTE_MIN_VERSION) \
if self.attributes else None
@property
def sync(self):
return self.attributes.get(ATTRIBUTE_SYNC) \
if self.attributes else None
class Interface(ReferenceKind):
ReferenceKind.AddSharedProperty('module')
ReferenceKind.AddSharedProperty('name')
ReferenceKind.AddSharedProperty('imported_from')
ReferenceKind.AddSharedProperty('methods')
ReferenceKind.AddSharedProperty('attributes')
def __init__(self, name=None, module=None, attributes=None):
if name is not None:
spec = 'x:' + name
else:
spec = None
ReferenceKind.__init__(self, spec)
self.module = module
self.name = name
self.imported_from = None
self.methods = []
self.attributes = attributes
def Repr(self, as_ref=True):
if as_ref:
return '<%s name=%r>' % (self.__class__.__name__, self.name)
else:
return GenericRepr(self, {'name': False, 'attributes': False,
'methods': False})
def AddMethod(self, name, ordinal=None, attributes=None):
method = Method(self, name, ordinal, attributes)
self.methods.append(method)
return method
# TODO(451323): Remove when the language backends no longer rely on this.
@property
def client(self):
return None
class AssociatedInterface(ReferenceKind):
ReferenceKind.AddSharedProperty('kind')
def __init__(self, kind=None):
if kind is not None:
if not isinstance(kind, Interface):
raise Exception(
"Associated interface requires %r to be an interface." % kind.spec)
assert not kind.is_nullable
ReferenceKind.__init__(self, 'asso:' + kind.spec)
else:
ReferenceKind.__init__(self)
self.kind = kind
class EnumField(object):
def __init__(self, name=None, value=None, attributes=None,
numeric_value=None):
self.name = name
self.value = value
self.attributes = attributes
self.numeric_value = numeric_value
@property
def min_version(self):
return self.attributes.get(ATTRIBUTE_MIN_VERSION) \
if self.attributes else None
class Enum(Kind):
def __init__(self, name=None, module=None, attributes=None):
self.module = module
self.name = name
self.native_only = False
self.imported_from = None
if name is not None:
spec = 'x:' + name
else:
spec = None
Kind.__init__(self, spec)
self.fields = []
self.attributes = attributes
def Repr(self, as_ref=True):
if as_ref:
return '<%s name=%r>' % (self.__class__.__name__, self.name)
else:
return GenericRepr(self, {'name': False, 'fields': False})
@property
def extensible(self):
return self.attributes.get(ATTRIBUTE_EXTENSIBLE, False) \
if self.attributes else False
class Module(object):
def __init__(self, name=None, namespace=None, attributes=None):
self.name = name
self.path = name
self.namespace = namespace
self.structs = []
self.unions = []
self.interfaces = []
self.kinds = {}
self.attributes = attributes
def __repr__(self):
# Gives us a decent __repr__ for modules.
return self.Repr()
def Repr(self, as_ref=True):
if as_ref:
return '<%s name=%r namespace=%r>' % (
self.__class__.__name__, self.name, self.namespace)
else:
return GenericRepr(self, {'name': False, 'namespace': False,
'attributes': False, 'structs': False,
'interfaces': False, 'unions': False})
def AddInterface(self, name, attributes=None):
interface = Interface(name, self, attributes)
self.interfaces.append(interface)
return interface
def AddStruct(self, name, attributes=None):
struct = Struct(name, self, attributes)
self.structs.append(struct)
return struct
def AddUnion(self, name, attributes=None):
union = Union(name, self, attributes)
self.unions.append(union)
return union
def IsBoolKind(kind):
return kind.spec == BOOL.spec
def IsFloatKind(kind):
return kind.spec == FLOAT.spec
def IsDoubleKind(kind):
return kind.spec == DOUBLE.spec
def IsIntegralKind(kind):
return (kind.spec == BOOL.spec or
kind.spec == INT8.spec or
kind.spec == INT16.spec or
kind.spec == INT32.spec or
kind.spec == INT64.spec or
kind.spec == UINT8.spec or
kind.spec == UINT16.spec or
kind.spec == UINT32.spec or
kind.spec == UINT64.spec)
def IsStringKind(kind):
return kind.spec == STRING.spec or kind.spec == NULLABLE_STRING.spec
def IsGenericHandleKind(kind):
return kind.spec == HANDLE.spec or kind.spec == NULLABLE_HANDLE.spec
def IsDataPipeConsumerKind(kind):
return kind.spec == DCPIPE.spec or kind.spec == NULLABLE_DCPIPE.spec
def IsDataPipeProducerKind(kind):
return kind.spec == DPPIPE.spec or kind.spec == NULLABLE_DPPIPE.spec
def IsMessagePipeKind(kind):
return kind.spec == MSGPIPE.spec or kind.spec == NULLABLE_MSGPIPE.spec
def IsSharedBufferKind(kind):
return (kind.spec == SHAREDBUFFER.spec or
kind.spec == NULLABLE_SHAREDBUFFER.spec)
def IsStructKind(kind):
return isinstance(kind, Struct)
def IsUnionKind(kind):
return isinstance(kind, Union)
def IsArrayKind(kind):
return isinstance(kind, Array)
def IsInterfaceKind(kind):
return isinstance(kind, Interface)
def IsAssociatedInterfaceKind(kind):
return isinstance(kind, AssociatedInterface)
def IsInterfaceRequestKind(kind):
return isinstance(kind, InterfaceRequest)
def IsAssociatedInterfaceRequestKind(kind):
return isinstance(kind, AssociatedInterfaceRequest)
def IsEnumKind(kind):
return isinstance(kind, Enum)
def IsReferenceKind(kind):
return isinstance(kind, ReferenceKind)
def IsNullableKind(kind):
return IsReferenceKind(kind) and kind.is_nullable
def IsMapKind(kind):
return isinstance(kind, Map)
def IsObjectKind(kind):
return IsPointerKind(kind) or IsUnionKind(kind)
def IsPointerKind(kind):
return (IsStructKind(kind) or IsArrayKind(kind) or IsStringKind(kind) or
IsMapKind(kind))
# Please note that it doesn't include any interface kind.
def IsAnyHandleKind(kind):
return (IsGenericHandleKind(kind) or
IsDataPipeConsumerKind(kind) or
IsDataPipeProducerKind(kind) or
IsMessagePipeKind(kind) or
IsSharedBufferKind(kind))
def IsAnyInterfaceKind(kind):
return (IsInterfaceKind(kind) or IsInterfaceRequestKind(kind) or
IsAssociatedKind(kind))
def IsAnyHandleOrInterfaceKind(kind):
return IsAnyHandleKind(kind) or IsAnyInterfaceKind(kind)
def IsAssociatedKind(kind):
return (IsAssociatedInterfaceKind(kind) or
IsAssociatedInterfaceRequestKind(kind))
def HasCallbacks(interface):
for method in interface.methods:
if method.response_parameters != None:
return True
return False
# Finds out whether an interface passes associated interfaces and associated
# interface requests.
def PassesAssociatedKinds(interface):
def _ContainsAssociatedKinds(kind, visited_kinds):
if kind in visited_kinds:
# No need to examine the kind again.
return False
visited_kinds.add(kind)
if IsAssociatedKind(kind):
return True
if IsArrayKind(kind):
return _ContainsAssociatedKinds(kind.kind, visited_kinds)
if IsStructKind(kind) or IsUnionKind(kind):
for field in kind.fields:
if _ContainsAssociatedKinds(field.kind, visited_kinds):
return True
if IsMapKind(kind):
# No need to examine the key kind, only primitive kinds and non-nullable
# string are allowed to be key kinds.
return _ContainsAssociatedKinds(kind.value_kind, visited_kinds)
return False
visited_kinds = set()
for method in interface.methods:
for param in method.parameters:
if _ContainsAssociatedKinds(param.kind, visited_kinds):
return True
if method.response_parameters != None:
for param in method.response_parameters:
if _ContainsAssociatedKinds(param.kind, visited_kinds):
return True
return False
def HasSyncMethods(interface):
for method in interface.methods:
if method.sync:
return True
return False
def ContainsHandlesOrInterfaces(kind):
"""Check if the kind contains any handles.
This check is recursive so it checks all struct fields, containers elements,
etc.
Args:
struct: {Kind} The kind to check.
Returns:
{bool}: True if the kind contains handles.
"""
# We remember the types we already checked to avoid infinite recursion when
# checking recursive (or mutually recursive) types:
checked = set()
def Check(kind):
if kind.spec in checked:
return False
checked.add(kind.spec)
if IsStructKind(kind):
return any(Check(field.kind) for field in kind.fields)
elif IsUnionKind(kind):
return any(Check(field.kind) for field in kind.fields)
elif IsAnyHandleKind(kind):
return True
elif IsAnyInterfaceKind(kind):
return True
elif IsArrayKind(kind):
return Check(kind.kind)
elif IsMapKind(kind):
return Check(kind.key_kind) or Check(kind.value_kind)
else:
return False
return Check(kind)