xemu/scripts/qapi/schema.py
John Snow 3404e57410 qapi/parser: Don't try to handle file errors
Fixes: f5d4361cda
Fixes: 52a474180a
Fixes: 46f49468c6

Remove the try/except block that handles file-opening errors in
QAPISchemaParser.__init__() and add one each to
QAPISchemaParser._include() and QAPISchema.__init__() respectively.

This simultaneously fixes the typing of info.fname (f5d4361cda), A
static typing violation in test-qapi (46f49468c6), and a regression of
an error message (52a474180a).

The short-ish version of what motivates this patch is:

- It's hard to write a good error message in the init method,
  because we need to determine the context of our caller to do so.
  It's easier to just let the caller write the message.
- We don't want to allow QAPISourceInfo(None, None, None) to exist. The
  typing introduced by commit f5d4361cda types the 'fname' field as
  (non-optional) str, which was premature until the removal of this
  construct.
- Errors made using such an object are currently incorrect (since
  52a474180a)
- It's not technically a semantic error if we cannot open the schema.
- There are various typing constraints that make mixing these two cases
  undesirable for a single special case.
- test-qapi's code handling an fname of 'None' is now dead, drop it.
  Additionally, Not all QAPIError objects have an 'info' field (since
  46f49468), so deleting this stanza corrects a typing oversight in
  test-qapi introduced by that commit.

Other considerations:

- open() is moved to a 'with' block to ensure file pointers are
  cleaned up deterministically.
- Python 3.3 deprecated IOError and made it a synonym for OSError.
  Avoid the misleading perception these exception handlers are
  narrower than they really are.

The long version:

The error message here is incorrect (since commit 52a474180a):

> python3 qapi-gen.py 'fake.json'
qapi-gen.py: qapi-gen.py: can't read schema file 'fake.json': No such file or directory

In pursuing it, we find that QAPISourceInfo has a special accommodation
for when there's no filename. Meanwhile, the intent when QAPISourceInfo
was typed (f5d4361cda) was non-optional 'str'. This usage was
overlooked.

To remove this, I'd want to avoid having a "fake" QAPISourceInfo
object. I also don't want to explicitly begin accommodating
QAPISourceInfo itself being None, because we actually want to eventually
prove that this can never happen -- We don't want to confuse "The file
isn't open yet" with "This error stems from a definition that wasn't
defined in any file".

(An earlier series tried to create a dummy info object, but it was tough
to prove in review that it worked correctly without creating new
regressions. This patch avoids that distraction. We would like to first
prove that we never raise QAPISemError for any built-in object before we
add "special" info objects. We aren't ready to do that yet.)

So, which way out of the labyrinth?

Here's one way: Don't try to handle errors at a level with "mixed"
semantic contexts; i.e. don't mix inclusion errors (should report a
source line where the include was triggered) and command line errors
(where we specified a file we couldn't read).

Remove the error handling from the initializer of the parser. Pythonic!
Now it's the caller's job to figure out what to do about it. Handle the
error in QAPISchemaParser._include() instead, where we can write a
targeted error message where we are guaranteed to have an 'info' context
to report with.

The root level error can similarly move to QAPISchema.__init__(), where
we know we'll never have an info context to report with, so we use a
more abstract error type.

Now the error looks sensible again:

> python3 qapi-gen.py 'fake.json'
qapi-gen.py: can't read schema file 'fake.json': No such file or directory

With these error cases separated, QAPISourceInfo can be solidified as
never having placeholder arguments that violate our desired types. Clean
up test-qapi along similar lines.

Signed-off-by: John Snow <jsnow@redhat.com>
Message-Id: <20210519183951.3946870-2-jsnow@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2021-05-20 11:28:27 +02:00

1184 lines
42 KiB
Python

# -*- coding: utf-8 -*-
#
# QAPI schema internal representation
#
# Copyright (c) 2015-2019 Red Hat Inc.
#
# Authors:
# Markus Armbruster <armbru@redhat.com>
# Eric Blake <eblake@redhat.com>
# Marc-André Lureau <marcandre.lureau@redhat.com>
#
# This work is licensed under the terms of the GNU GPL, version 2.
# See the COPYING file in the top-level directory.
# TODO catching name collisions in generated code would be nice
from collections import OrderedDict
import os
import re
from typing import Optional
from .common import POINTER_SUFFIX, c_name
from .error import QAPIError, QAPISemError, QAPISourceError
from .expr import check_exprs
from .parser import QAPISchemaParser
class QAPISchemaEntity:
meta: Optional[str] = None
def __init__(self, name: str, info, doc, ifcond=None, features=None):
assert name is None or isinstance(name, str)
for f in features or []:
assert isinstance(f, QAPISchemaFeature)
f.set_defined_in(name)
self.name = name
self._module = None
# For explicitly defined entities, info points to the (explicit)
# definition. For builtins (and their arrays), info is None.
# For implicitly defined entities, info points to a place that
# triggered the implicit definition (there may be more than one
# such place).
self.info = info
self.doc = doc
self._ifcond = ifcond or []
self.features = features or []
self._checked = False
def c_name(self):
return c_name(self.name)
def check(self, schema):
assert not self._checked
seen = {}
for f in self.features:
f.check_clash(self.info, seen)
self._checked = True
def connect_doc(self, doc=None):
doc = doc or self.doc
if doc:
for f in self.features:
doc.connect_feature(f)
def check_doc(self):
if self.doc:
self.doc.check()
def _set_module(self, schema, info):
assert self._checked
fname = info.fname if info else QAPISchemaModule.BUILTIN_MODULE_NAME
self._module = schema.module_by_fname(fname)
self._module.add_entity(self)
def set_module(self, schema):
self._set_module(schema, self.info)
@property
def ifcond(self):
assert self._checked
return self._ifcond
def is_implicit(self):
return not self.info
def visit(self, visitor):
assert self._checked
def describe(self):
assert self.meta
return "%s '%s'" % (self.meta, self.name)
class QAPISchemaVisitor:
def visit_begin(self, schema):
pass
def visit_end(self):
pass
def visit_module(self, name):
pass
def visit_needed(self, entity):
# Default to visiting everything
return True
def visit_include(self, name, info):
pass
def visit_builtin_type(self, name, info, json_type):
pass
def visit_enum_type(self, name, info, ifcond, features, members, prefix):
pass
def visit_array_type(self, name, info, ifcond, element_type):
pass
def visit_object_type(self, name, info, ifcond, features,
base, members, variants):
pass
def visit_object_type_flat(self, name, info, ifcond, features,
members, variants):
pass
def visit_alternate_type(self, name, info, ifcond, features, variants):
pass
def visit_command(self, name, info, ifcond, features,
arg_type, ret_type, gen, success_response, boxed,
allow_oob, allow_preconfig, coroutine):
pass
def visit_event(self, name, info, ifcond, features, arg_type, boxed):
pass
class QAPISchemaModule:
BUILTIN_MODULE_NAME = './builtin'
def __init__(self, name):
self.name = name
self._entity_list = []
@staticmethod
def is_system_module(name: str) -> bool:
"""
System modules are internally defined modules.
Their names start with the "./" prefix.
"""
return name.startswith('./')
@classmethod
def is_user_module(cls, name: str) -> bool:
"""
User modules are those defined by the user in qapi JSON files.
They do not start with the "./" prefix.
"""
return not cls.is_system_module(name)
@classmethod
def is_builtin_module(cls, name: str) -> bool:
"""
The built-in module is a single System module for the built-in types.
It is always "./builtin".
"""
return name == cls.BUILTIN_MODULE_NAME
def add_entity(self, ent):
self._entity_list.append(ent)
def visit(self, visitor):
visitor.visit_module(self.name)
for entity in self._entity_list:
if visitor.visit_needed(entity):
entity.visit(visitor)
class QAPISchemaInclude(QAPISchemaEntity):
def __init__(self, sub_module, info):
super().__init__(None, info, None)
self._sub_module = sub_module
def visit(self, visitor):
super().visit(visitor)
visitor.visit_include(self._sub_module.name, self.info)
class QAPISchemaType(QAPISchemaEntity):
# Return the C type for common use.
# For the types we commonly box, this is a pointer type.
def c_type(self):
pass
# 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
def alternate_qtype(self):
json2qtype = {
'null': 'QTYPE_QNULL',
'string': 'QTYPE_QSTRING',
'number': 'QTYPE_QNUM',
'int': 'QTYPE_QNUM',
'boolean': 'QTYPE_QBOOL',
'object': 'QTYPE_QDICT'
}
return json2qtype.get(self.json_type())
def doc_type(self):
if self.is_implicit():
return None
return self.name
def check(self, schema):
QAPISchemaEntity.check(self, schema)
if 'deprecated' in [f.name for f in self.features]:
raise QAPISemError(
self.info, "feature 'deprecated' is not supported for types")
def describe(self):
assert self.meta
return "%s type '%s'" % (self.meta, self.name)
class QAPISchemaBuiltinType(QAPISchemaType):
meta = 'built-in'
def __init__(self, name, json_type, c_type):
super().__init__(name, None, 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
def c_name(self):
return self.name
def c_type(self):
return self._c_type_name
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
def doc_type(self):
return self.json_type()
def visit(self, visitor):
super().visit(visitor)
visitor.visit_builtin_type(self.name, self.info, self.json_type())
class QAPISchemaEnumType(QAPISchemaType):
meta = 'enum'
def __init__(self, name, info, doc, ifcond, features, members, prefix):
super().__init__(name, info, doc, ifcond, features)
for m in members:
assert isinstance(m, QAPISchemaEnumMember)
m.set_defined_in(name)
assert prefix is None or isinstance(prefix, str)
self.members = members
self.prefix = prefix
def check(self, schema):
super().check(schema)
seen = {}
for m in self.members:
m.check_clash(self.info, seen)
def connect_doc(self, doc=None):
super().connect_doc(doc)
doc = doc or self.doc
for m in self.members:
m.connect_doc(doc)
def is_implicit(self):
# See QAPISchema._make_implicit_enum_type() and ._def_predefineds()
return self.name.endswith('Kind') or self.name == 'QType'
def c_type(self):
return c_name(self.name)
def member_names(self):
return [m.name for m in self.members]
def json_type(self):
return 'string'
def visit(self, visitor):
super().visit(visitor)
visitor.visit_enum_type(
self.name, self.info, self.ifcond, self.features,
self.members, self.prefix)
class QAPISchemaArrayType(QAPISchemaType):
meta = 'array'
def __init__(self, name, info, element_type):
super().__init__(name, info, None)
assert isinstance(element_type, str)
self._element_type_name = element_type
self.element_type = None
def check(self, schema):
super().check(schema)
self.element_type = schema.resolve_type(
self._element_type_name, self.info,
self.info and self.info.defn_meta)
assert not isinstance(self.element_type, QAPISchemaArrayType)
def set_module(self, schema):
self._set_module(schema, self.element_type.info)
@property
def ifcond(self):
assert self._checked
return self.element_type.ifcond
def is_implicit(self):
return True
def c_type(self):
return c_name(self.name) + POINTER_SUFFIX
def json_type(self):
return 'array'
def doc_type(self):
elt_doc_type = self.element_type.doc_type()
if not elt_doc_type:
return None
return 'array of ' + elt_doc_type
def visit(self, visitor):
super().visit(visitor)
visitor.visit_array_type(self.name, self.info, self.ifcond,
self.element_type)
def describe(self):
assert self.meta
return "%s type ['%s']" % (self.meta, self._element_type_name)
class QAPISchemaObjectType(QAPISchemaType):
def __init__(self, name, info, doc, ifcond, features,
base, local_members, variants):
# struct has local_members, optional base, and no variants
# flat union has base, variants, and no local_members
# simple union has local_members, variants, and no base
super().__init__(name, info, doc, ifcond, features)
self.meta = 'union' if variants else 'struct'
assert base is None or isinstance(base, str)
for m in local_members:
assert isinstance(m, QAPISchemaObjectTypeMember)
m.set_defined_in(name)
if variants is not None:
assert isinstance(variants, QAPISchemaVariants)
variants.set_defined_in(name)
self._base_name = base
self.base = None
self.local_members = local_members
self.variants = variants
self.members = None
def check(self, schema):
# This calls another type T's .check() exactly when the C
# struct emitted by gen_object() contains that T's C struct
# (pointers don't count).
if self.members is not None:
# A previous .check() completed: nothing to do
return
if self._checked:
# Recursed: C struct contains itself
raise QAPISemError(self.info,
"object %s contains itself" % self.name)
super().check(schema)
assert self._checked and self.members is None
seen = OrderedDict()
if self._base_name:
self.base = schema.resolve_type(self._base_name, self.info,
"'base'")
if (not isinstance(self.base, QAPISchemaObjectType)
or self.base.variants):
raise QAPISemError(
self.info,
"'base' requires a struct type, %s isn't"
% self.base.describe())
self.base.check(schema)
self.base.check_clash(self.info, seen)
for m in self.local_members:
m.check(schema)
m.check_clash(self.info, seen)
members = seen.values()
if self.variants:
self.variants.check(schema, seen)
self.variants.check_clash(self.info, seen)
self.members = members # mark completed
# 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, info, seen):
assert self._checked
assert not self.variants # not implemented
for m in self.members:
m.check_clash(info, seen)
def connect_doc(self, doc=None):
super().connect_doc(doc)
doc = doc or self.doc
if self.base and self.base.is_implicit():
self.base.connect_doc(doc)
for m in self.local_members:
m.connect_doc(doc)
@property
def ifcond(self):
assert self._checked
if isinstance(self._ifcond, QAPISchemaType):
# Simple union wrapper type inherits from wrapped type;
# see _make_implicit_object_type()
return self._ifcond.ifcond
return self._ifcond
def is_implicit(self):
# 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 self.name != 'q_empty'
return super().c_name()
def c_type(self):
assert not self.is_implicit()
return c_name(self.name) + POINTER_SUFFIX
def c_unboxed_type(self):
return c_name(self.name)
def json_type(self):
return 'object'
def visit(self, visitor):
super().visit(visitor)
visitor.visit_object_type(
self.name, self.info, self.ifcond, self.features,
self.base, self.local_members, self.variants)
visitor.visit_object_type_flat(
self.name, self.info, self.ifcond, self.features,
self.members, self.variants)
class QAPISchemaAlternateType(QAPISchemaType):
meta = 'alternate'
def __init__(self, name, info, doc, ifcond, features, variants):
super().__init__(name, info, doc, ifcond, features)
assert isinstance(variants, QAPISchemaVariants)
assert variants.tag_member
variants.set_defined_in(name)
variants.tag_member.set_defined_in(self.name)
self.variants = variants
def check(self, schema):
super().check(schema)
self.variants.tag_member.check(schema)
# 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 = {}
types_seen = {}
for v in self.variants.variants:
v.check_clash(self.info, seen)
qtype = v.type.alternate_qtype()
if not qtype:
raise QAPISemError(
self.info,
"%s cannot use %s"
% (v.describe(self.info), v.type.describe()))
conflicting = set([qtype])
if qtype == 'QTYPE_QSTRING':
if isinstance(v.type, QAPISchemaEnumType):
for m in v.type.members:
if m.name in ['on', 'off']:
conflicting.add('QTYPE_QBOOL')
if re.match(r'[-+0-9.]', m.name):
# lazy, could be tightened
conflicting.add('QTYPE_QNUM')
else:
conflicting.add('QTYPE_QNUM')
conflicting.add('QTYPE_QBOOL')
for qt in conflicting:
if qt in types_seen:
raise QAPISemError(
self.info,
"%s can't be distinguished from '%s'"
% (v.describe(self.info), types_seen[qt]))
types_seen[qt] = v.name
def connect_doc(self, doc=None):
super().connect_doc(doc)
doc = doc or self.doc
for v in self.variants.variants:
v.connect_doc(doc)
def c_type(self):
return c_name(self.name) + POINTER_SUFFIX
def json_type(self):
return 'value'
def visit(self, visitor):
super().visit(visitor)
visitor.visit_alternate_type(
self.name, self.info, self.ifcond, self.features, self.variants)
class QAPISchemaVariants:
def __init__(self, tag_name, info, tag_member, variants):
# Flat unions pass tag_name but not tag_member.
# Simple unions and alternates pass tag_member but not tag_name.
# After check(), tag_member is always set, and tag_name remains
# a reliable witness of being used by a flat union.
assert bool(tag_member) != bool(tag_name)
assert (isinstance(tag_name, str) or
isinstance(tag_member, QAPISchemaObjectTypeMember))
for v in variants:
assert isinstance(v, QAPISchemaVariant)
self._tag_name = tag_name
self.info = info
self.tag_member = tag_member
self.variants = variants
def set_defined_in(self, name):
for v in self.variants:
v.set_defined_in(name)
def check(self, schema, seen):
if not self.tag_member: # flat union
self.tag_member = seen.get(c_name(self._tag_name))
base = "'base'"
# Pointing to the base type when not implicit would be
# nice, but we don't know it here
if not self.tag_member or self._tag_name != self.tag_member.name:
raise QAPISemError(
self.info,
"discriminator '%s' is not a member of %s"
% (self._tag_name, base))
# Here we do:
base_type = schema.lookup_type(self.tag_member.defined_in)
assert base_type
if not base_type.is_implicit():
base = "base type '%s'" % self.tag_member.defined_in
if not isinstance(self.tag_member.type, QAPISchemaEnumType):
raise QAPISemError(
self.info,
"discriminator member '%s' of %s must be of enum type"
% (self._tag_name, base))
if self.tag_member.optional:
raise QAPISemError(
self.info,
"discriminator member '%s' of %s must not be optional"
% (self._tag_name, base))
if self.tag_member.ifcond:
raise QAPISemError(
self.info,
"discriminator member '%s' of %s must not be conditional"
% (self._tag_name, base))
else: # simple union
assert isinstance(self.tag_member.type, QAPISchemaEnumType)
assert not self.tag_member.optional
assert self.tag_member.ifcond == []
if self._tag_name: # flat union
# branches that are not explicitly covered get an empty type
cases = {v.name for v in self.variants}
for m in self.tag_member.type.members:
if m.name not in cases:
v = QAPISchemaVariant(m.name, self.info,
'q_empty', m.ifcond)
v.set_defined_in(self.tag_member.defined_in)
self.variants.append(v)
if not self.variants:
raise QAPISemError(self.info, "union has no branches")
for v in self.variants:
v.check(schema)
# Union names must match enum values; alternate names are
# checked separately. Use 'seen' to tell the two apart.
if seen:
if v.name not in self.tag_member.type.member_names():
raise QAPISemError(
self.info,
"branch '%s' is not a value of %s"
% (v.name, self.tag_member.type.describe()))
if (not isinstance(v.type, QAPISchemaObjectType)
or v.type.variants):
raise QAPISemError(
self.info,
"%s cannot use %s"
% (v.describe(self.info), v.type.describe()))
v.type.check(schema)
def check_clash(self, info, seen):
for v in self.variants:
# Reset seen map for each variant, since qapi names from one
# branch do not affect another branch
v.type.check_clash(info, dict(seen))
class QAPISchemaMember:
""" Represents object members, enum members and features """
role = 'member'
def __init__(self, name, info, ifcond=None):
assert isinstance(name, str)
self.name = name
self.info = info
self.ifcond = ifcond or []
self.defined_in = None
def set_defined_in(self, name):
assert not self.defined_in
self.defined_in = name
def check_clash(self, info, seen):
cname = c_name(self.name)
if cname in seen:
raise QAPISemError(
info,
"%s collides with %s"
% (self.describe(info), seen[cname].describe(info)))
seen[cname] = self
def connect_doc(self, doc):
if doc:
doc.connect_member(self)
def describe(self, info):
role = self.role
defined_in = self.defined_in
assert defined_in
if defined_in.startswith('q_obj_'):
# See QAPISchema._make_implicit_object_type() - reverse the
# mapping there to create a nice human-readable description
defined_in = defined_in[6:]
if defined_in.endswith('-arg'):
# Implicit type created for a command's dict 'data'
assert role == 'member'
role = 'parameter'
elif defined_in.endswith('-base'):
# Implicit type created for a flat union's dict 'base'
role = 'base ' + role
else:
# Implicit type created for a simple union's branch
assert defined_in.endswith('-wrapper')
# Unreachable and not implemented
assert False
elif defined_in.endswith('Kind'):
# See QAPISchema._make_implicit_enum_type()
# Implicit enum created for simple union's branches
assert role == 'value'
role = 'branch'
elif defined_in != info.defn_name:
return "%s '%s' of type '%s'" % (role, self.name, defined_in)
return "%s '%s'" % (role, self.name)
class QAPISchemaEnumMember(QAPISchemaMember):
role = 'value'
class QAPISchemaFeature(QAPISchemaMember):
role = 'feature'
class QAPISchemaObjectTypeMember(QAPISchemaMember):
def __init__(self, name, info, typ, optional, ifcond=None, features=None):
super().__init__(name, info, ifcond)
assert isinstance(typ, str)
assert isinstance(optional, bool)
for f in features or []:
assert isinstance(f, QAPISchemaFeature)
f.set_defined_in(name)
self._type_name = typ
self.type = None
self.optional = optional
self.features = features or []
def check(self, schema):
assert self.defined_in
self.type = schema.resolve_type(self._type_name, self.info,
self.describe)
seen = {}
for f in self.features:
f.check_clash(self.info, seen)
def connect_doc(self, doc):
super().connect_doc(doc)
if doc:
for f in self.features:
doc.connect_feature(f)
class QAPISchemaVariant(QAPISchemaObjectTypeMember):
role = 'branch'
def __init__(self, name, info, typ, ifcond=None):
super().__init__(name, info, typ, False, ifcond)
class QAPISchemaCommand(QAPISchemaEntity):
meta = 'command'
def __init__(self, name, info, doc, ifcond, features,
arg_type, ret_type,
gen, success_response, boxed, allow_oob, allow_preconfig,
coroutine):
super().__init__(name, info, doc, ifcond, features)
assert not arg_type or isinstance(arg_type, str)
assert not ret_type or isinstance(ret_type, str)
self._arg_type_name = arg_type
self.arg_type = None
self._ret_type_name = ret_type
self.ret_type = None
self.gen = gen
self.success_response = success_response
self.boxed = boxed
self.allow_oob = allow_oob
self.allow_preconfig = allow_preconfig
self.coroutine = coroutine
def check(self, schema):
super().check(schema)
if self._arg_type_name:
self.arg_type = schema.resolve_type(
self._arg_type_name, self.info, "command's 'data'")
if not isinstance(self.arg_type, QAPISchemaObjectType):
raise QAPISemError(
self.info,
"command's 'data' cannot take %s"
% self.arg_type.describe())
if self.arg_type.variants and not self.boxed:
raise QAPISemError(
self.info,
"command's 'data' can take %s only with 'boxed': true"
% self.arg_type.describe())
if self._ret_type_name:
self.ret_type = schema.resolve_type(
self._ret_type_name, self.info, "command's 'returns'")
if self.name not in self.info.pragma.command_returns_exceptions:
typ = self.ret_type
if isinstance(typ, QAPISchemaArrayType):
typ = self.ret_type.element_type
assert typ
if not isinstance(typ, QAPISchemaObjectType):
raise QAPISemError(
self.info,
"command's 'returns' cannot take %s"
% self.ret_type.describe())
def connect_doc(self, doc=None):
super().connect_doc(doc)
doc = doc or self.doc
if doc:
if self.arg_type and self.arg_type.is_implicit():
self.arg_type.connect_doc(doc)
def visit(self, visitor):
super().visit(visitor)
visitor.visit_command(
self.name, self.info, self.ifcond, self.features,
self.arg_type, self.ret_type, self.gen, self.success_response,
self.boxed, self.allow_oob, self.allow_preconfig,
self.coroutine)
class QAPISchemaEvent(QAPISchemaEntity):
meta = 'event'
def __init__(self, name, info, doc, ifcond, features, arg_type, boxed):
super().__init__(name, info, doc, ifcond, features)
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):
super().check(schema)
if self._arg_type_name:
self.arg_type = schema.resolve_type(
self._arg_type_name, self.info, "event's 'data'")
if not isinstance(self.arg_type, QAPISchemaObjectType):
raise QAPISemError(
self.info,
"event's 'data' cannot take %s"
% self.arg_type.describe())
if self.arg_type.variants and not self.boxed:
raise QAPISemError(
self.info,
"event's 'data' can take %s only with 'boxed': true"
% self.arg_type.describe())
def connect_doc(self, doc=None):
super().connect_doc(doc)
doc = doc or self.doc
if doc:
if self.arg_type and self.arg_type.is_implicit():
self.arg_type.connect_doc(doc)
def visit(self, visitor):
super().visit(visitor)
visitor.visit_event(
self.name, self.info, self.ifcond, self.features,
self.arg_type, self.boxed)
class QAPISchema:
def __init__(self, fname):
self.fname = fname
try:
parser = QAPISchemaParser(fname)
except OSError as err:
raise QAPIError(
f"can't read schema file '{fname}': {err.strerror}"
) from err
exprs = check_exprs(parser.exprs)
self.docs = parser.docs
self._entity_list = []
self._entity_dict = {}
self._module_dict = OrderedDict()
self._schema_dir = os.path.dirname(fname)
self._make_module(QAPISchemaModule.BUILTIN_MODULE_NAME)
self._make_module(fname)
self._predefining = True
self._def_predefineds()
self._predefining = False
self._def_exprs(exprs)
self.check()
def _def_entity(self, ent):
# Only the predefined types are allowed to not have info
assert ent.info or self._predefining
self._entity_list.append(ent)
if ent.name is None:
return
# TODO reject names that differ only in '_' vs. '.' vs. '-',
# because they're liable to clash in generated C.
other_ent = self._entity_dict.get(ent.name)
if other_ent:
if other_ent.info:
where = QAPISourceError(other_ent.info, "previous definition")
raise QAPISemError(
ent.info,
"'%s' is already defined\n%s" % (ent.name, where))
raise QAPISemError(
ent.info, "%s is already defined" % other_ent.describe())
self._entity_dict[ent.name] = ent
def lookup_entity(self, name, typ=None):
ent = self._entity_dict.get(name)
if typ and not isinstance(ent, typ):
return None
return ent
def lookup_type(self, name):
return self.lookup_entity(name, QAPISchemaType)
def resolve_type(self, name, info, what):
typ = self.lookup_type(name)
if not typ:
if callable(what):
what = what(info)
raise QAPISemError(
info, "%s uses unknown type '%s'" % (what, name))
return typ
def _module_name(self, fname: str) -> str:
if QAPISchemaModule.is_system_module(fname):
return fname
return os.path.relpath(fname, self._schema_dir)
def _make_module(self, fname):
name = self._module_name(fname)
if name not in self._module_dict:
self._module_dict[name] = QAPISchemaModule(name)
return self._module_dict[name]
def module_by_fname(self, fname):
name = self._module_name(fname)
return self._module_dict[name]
def _def_include(self, expr, info, doc):
include = expr['include']
assert doc is None
self._def_entity(QAPISchemaInclude(self._make_module(include), info))
def _def_builtin_type(self, name, json_type, c_type):
self._def_entity(QAPISchemaBuiltinType(name, json_type, c_type))
# Instantiating only the arrays that are actually used would
# be nice, but we can't as long as their generated code
# (qapi-builtin-types.[ch]) may be shared by some other
# schema.
self._make_array_type(name, None)
def _def_predefineds(self):
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),
('null', 'null', 'QNull' + POINTER_SUFFIX)]:
self._def_builtin_type(*t)
self.the_empty_object_type = QAPISchemaObjectType(
'q_empty', None, None, None, None, None, [], None)
self._def_entity(self.the_empty_object_type)
qtypes = ['none', 'qnull', 'qnum', 'qstring', 'qdict', 'qlist',
'qbool']
qtype_values = self._make_enum_members(
[{'name': n} for n in qtypes], None)
self._def_entity(QAPISchemaEnumType('QType', None, None, None, None,
qtype_values, 'QTYPE'))
def _make_features(self, features, info):
if features is None:
return []
return [QAPISchemaFeature(f['name'], info, f.get('if'))
for f in features]
def _make_enum_members(self, values, info):
return [QAPISchemaEnumMember(v['name'], info, v.get('if'))
for v in values]
def _make_implicit_enum_type(self, name, info, ifcond, values):
# See also QAPISchemaObjectTypeMember.describe()
name = name + 'Kind' # reserved by check_defn_name_str()
self._def_entity(QAPISchemaEnumType(
name, info, None, ifcond, None,
self._make_enum_members(values, info),
None))
return name
def _make_array_type(self, element_type, info):
name = element_type + 'List' # reserved by check_defn_name_str()
if not self.lookup_type(name):
self._def_entity(QAPISchemaArrayType(name, info, element_type))
return name
def _make_implicit_object_type(self, name, info, ifcond, role, members):
if not members:
return None
# See also QAPISchemaObjectTypeMember.describe()
name = 'q_obj_%s-%s' % (name, role)
typ = self.lookup_entity(name, QAPISchemaObjectType)
if typ:
# The implicit object type has multiple users. This can
# happen only for simple unions' implicit wrapper types.
# Its ifcond should be the disjunction of its user's
# ifconds. Not implemented. Instead, we always pass the
# wrapped type's ifcond, which is trivially the same for all
# users. It's also necessary for the wrapper to compile.
# But it's not tight: the disjunction need not imply it. We
# may end up compiling useless wrapper types.
# TODO kill simple unions or implement the disjunction
# pylint: disable=protected-access
assert (ifcond or []) == typ._ifcond
else:
self._def_entity(QAPISchemaObjectType(
name, info, None, ifcond, None, None, members, None))
return name
def _def_enum_type(self, expr, info, doc):
name = expr['enum']
data = expr['data']
prefix = expr.get('prefix')
ifcond = expr.get('if')
features = self._make_features(expr.get('features'), info)
self._def_entity(QAPISchemaEnumType(
name, info, doc, ifcond, features,
self._make_enum_members(data, info), prefix))
def _make_member(self, name, typ, ifcond, features, info):
optional = False
if name.startswith('*'):
name = name[1:]
optional = True
if isinstance(typ, list):
assert len(typ) == 1
typ = self._make_array_type(typ[0], info)
return QAPISchemaObjectTypeMember(name, info, typ, optional, ifcond,
self._make_features(features, info))
def _make_members(self, data, info):
return [self._make_member(key, value['type'], value.get('if'),
value.get('features'), info)
for (key, value) in data.items()]
def _def_struct_type(self, expr, info, doc):
name = expr['struct']
base = expr.get('base')
data = expr['data']
ifcond = expr.get('if')
features = self._make_features(expr.get('features'), info)
self._def_entity(QAPISchemaObjectType(
name, info, doc, ifcond, features, base,
self._make_members(data, info),
None))
def _make_variant(self, case, typ, ifcond, info):
return QAPISchemaVariant(case, info, typ, ifcond)
def _make_simple_variant(self, case, typ, ifcond, info):
if isinstance(typ, list):
assert len(typ) == 1
typ = self._make_array_type(typ[0], info)
typ = self._make_implicit_object_type(
typ, info, self.lookup_type(typ),
'wrapper', [self._make_member('data', typ, None, None, info)])
return QAPISchemaVariant(case, info, typ, ifcond)
def _def_union_type(self, expr, info, doc):
name = expr['union']
data = expr['data']
base = expr.get('base')
ifcond = expr.get('if')
features = self._make_features(expr.get('features'), info)
tag_name = expr.get('discriminator')
tag_member = None
if isinstance(base, dict):
base = self._make_implicit_object_type(
name, info, ifcond,
'base', self._make_members(base, info))
if tag_name:
variants = [self._make_variant(key, value['type'],
value.get('if'), info)
for (key, value) in data.items()]
members = []
else:
variants = [self._make_simple_variant(key, value['type'],
value.get('if'), info)
for (key, value) in data.items()]
enum = [{'name': v.name, 'if': v.ifcond} for v in variants]
typ = self._make_implicit_enum_type(name, info, ifcond, enum)
tag_member = QAPISchemaObjectTypeMember('type', info, typ, False)
members = [tag_member]
self._def_entity(
QAPISchemaObjectType(name, info, doc, ifcond, features,
base, members,
QAPISchemaVariants(
tag_name, info, tag_member, variants)))
def _def_alternate_type(self, expr, info, doc):
name = expr['alternate']
data = expr['data']
ifcond = expr.get('if')
features = self._make_features(expr.get('features'), info)
variants = [self._make_variant(key, value['type'], value.get('if'),
info)
for (key, value) in data.items()]
tag_member = QAPISchemaObjectTypeMember('type', info, 'QType', False)
self._def_entity(
QAPISchemaAlternateType(name, info, doc, ifcond, features,
QAPISchemaVariants(
None, info, tag_member, variants)))
def _def_command(self, expr, info, doc):
name = expr['command']
data = expr.get('data')
rets = expr.get('returns')
gen = expr.get('gen', True)
success_response = expr.get('success-response', True)
boxed = expr.get('boxed', False)
allow_oob = expr.get('allow-oob', False)
allow_preconfig = expr.get('allow-preconfig', False)
coroutine = expr.get('coroutine', False)
ifcond = expr.get('if')
features = self._make_features(expr.get('features'), info)
if isinstance(data, OrderedDict):
data = self._make_implicit_object_type(
name, info, ifcond,
'arg', self._make_members(data, info))
if isinstance(rets, list):
assert len(rets) == 1
rets = self._make_array_type(rets[0], info)
self._def_entity(QAPISchemaCommand(name, info, doc, ifcond, features,
data, rets,
gen, success_response,
boxed, allow_oob, allow_preconfig,
coroutine))
def _def_event(self, expr, info, doc):
name = expr['event']
data = expr.get('data')
boxed = expr.get('boxed', False)
ifcond = expr.get('if')
features = self._make_features(expr.get('features'), info)
if isinstance(data, OrderedDict):
data = self._make_implicit_object_type(
name, info, ifcond,
'arg', self._make_members(data, info))
self._def_entity(QAPISchemaEvent(name, info, doc, ifcond, features,
data, boxed))
def _def_exprs(self, exprs):
for expr_elem in exprs:
expr = expr_elem['expr']
info = expr_elem['info']
doc = expr_elem.get('doc')
if 'enum' in expr:
self._def_enum_type(expr, info, doc)
elif 'struct' in expr:
self._def_struct_type(expr, info, doc)
elif 'union' in expr:
self._def_union_type(expr, info, doc)
elif 'alternate' in expr:
self._def_alternate_type(expr, info, doc)
elif 'command' in expr:
self._def_command(expr, info, doc)
elif 'event' in expr:
self._def_event(expr, info, doc)
elif 'include' in expr:
self._def_include(expr, info, doc)
else:
assert False
def check(self):
for ent in self._entity_list:
ent.check(self)
ent.connect_doc()
ent.check_doc()
for ent in self._entity_list:
ent.set_module(self)
def visit(self, visitor):
visitor.visit_begin(self)
for mod in self._module_dict.values():
mod.visit(visitor)
visitor.visit_end()