qemu/scripts/qapi-introspect.py
Markus Armbruster 1a9a507b2e qapi-introspect: Hide type names
To eliminate the temptation for clients to look up types by name
(which are not ABI), replace all type names by meaningless strings.

Reduces output of query-schema by 13 out of 85KiB.

As a debugging aid, provide option -u to suppress the hiding.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1442401589-24189-27-git-send-email-armbru@redhat.com>
2015-09-21 09:56:49 +02:00

214 lines
6.8 KiB
Python

#
# QAPI introspection generator
#
# Copyright (C) 2015 Red Hat, Inc.
#
# Authors:
# Markus Armbruster <armbru@redhat.com>
#
# This work is licensed under the terms of the GNU GPL, version 2.
# See the COPYING file in the top-level directory.
from qapi import *
# Caveman's json.dumps() replacement (we're stuck at Python 2.4)
# TODO try to use json.dumps() once we get unstuck
def to_json(obj, level=0):
if obj is None:
ret = 'null'
elif isinstance(obj, str):
ret = '"' + obj.replace('"', r'\"') + '"'
elif isinstance(obj, list):
elts = [to_json(elt, level + 1)
for elt in obj]
ret = '[' + ', '.join(elts) + ']'
elif isinstance(obj, dict):
elts = ['"%s": %s' % (key.replace('"', r'\"'),
to_json(obj[key], level + 1))
for key in sorted(obj.keys())]
ret = '{' + ', '.join(elts) + '}'
else:
assert False # not implemented
if level == 1:
ret = '\n' + ret
return ret
def to_c_string(string):
return '"' + string.replace('\\', r'\\').replace('"', r'\"') + '"'
class QAPISchemaGenIntrospectVisitor(QAPISchemaVisitor):
def __init__(self, unmask):
self._unmask = unmask
self.defn = None
self.decl = None
self._schema = None
self._jsons = None
self._used_types = None
self._name_map = None
def visit_begin(self, schema):
self._schema = schema
self._jsons = []
self._used_types = []
self._name_map = {}
return QAPISchemaType # don't visit types for now
def visit_end(self):
# visit the types that are actually used
jsons = self._jsons
self._jsons = []
for typ in self._used_types:
typ.visit(self)
# generate C
# TODO can generate awfully long lines
jsons.extend(self._jsons)
name = prefix + 'qmp_schema_json'
self.decl = mcgen('''
extern const char %(c_name)s[];
''',
c_name=c_name(name))
lines = to_json(jsons).split('\n')
c_string = '\n '.join([to_c_string(line) for line in lines])
self.defn = mcgen('''
const char %(c_name)s[] = %(c_string)s;
''',
c_name=c_name(name),
c_string=c_string)
self._schema = None
self._jsons = None
self._used_types = None
self._name_map = None
def _name(self, name):
if self._unmask:
return name
if name not in self._name_map:
self._name_map[name] = '%d' % len(self._name_map)
return self._name_map[name]
def _use_type(self, typ):
# Map the various integer types to plain int
if typ.json_type() == 'int':
typ = self._schema.lookup_type('int')
elif (isinstance(typ, QAPISchemaArrayType) and
typ.element_type.json_type() == 'int'):
typ = self._schema.lookup_type('intList')
# Add type to work queue if new
if typ not in self._used_types:
self._used_types.append(typ)
# Clients should examine commands and events, not types. Hide
# type names to reduce the temptation. Also saves a few
# characters.
if isinstance(typ, QAPISchemaBuiltinType):
return typ.name
return self._name(typ.name)
def _gen_json(self, name, mtype, obj):
if mtype != 'command' and mtype != 'event' and mtype != 'builtin':
name = self._name(name)
obj['name'] = name
obj['meta-type'] = mtype
self._jsons.append(obj)
def _gen_member(self, member):
ret = {'name': member.name, 'type': self._use_type(member.type)}
if member.optional:
ret['default'] = None
return ret
def _gen_variants(self, tag_name, variants):
return {'tag': tag_name,
'variants': [self._gen_variant(v) for v in variants]}
def _gen_variant(self, variant):
return {'case': variant.name, 'type': self._use_type(variant.type)}
def visit_builtin_type(self, name, info, json_type):
self._gen_json(name, 'builtin', {'json-type': json_type})
def visit_enum_type(self, name, info, values, prefix):
self._gen_json(name, 'enum', {'values': values})
def visit_array_type(self, name, info, element_type):
self._gen_json(name, 'array',
{'element-type': self._use_type(element_type)})
def visit_object_type_flat(self, name, info, members, variants):
obj = {'members': [self._gen_member(m) for m in members]}
if variants:
obj.update(self._gen_variants(variants.tag_member.name,
variants.variants))
self._gen_json(name, 'object', obj)
def visit_alternate_type(self, name, info, variants):
self._gen_json(name, 'alternate',
{'members': [{'type': self._use_type(m.type)}
for m in variants.variants]})
def visit_command(self, name, info, arg_type, ret_type,
gen, success_response):
arg_type = arg_type or self._schema.the_empty_object_type
ret_type = ret_type or self._schema.the_empty_object_type
self._gen_json(name, 'command',
{'arg-type': self._use_type(arg_type),
'ret-type': self._use_type(ret_type)})
def visit_event(self, name, info, arg_type):
arg_type = arg_type or self._schema.the_empty_object_type
self._gen_json(name, 'event', {'arg-type': self._use_type(arg_type)})
# Debugging aid: unmask QAPI schema's type names
# We normally mask them, because they're not QMP wire ABI
opt_unmask = False
(input_file, output_dir, do_c, do_h, prefix, opts) = \
parse_command_line("u", ["unmask-non-abi-names"])
for o, a in opts:
if o in ("-u", "--unmask-non-abi-names"):
opt_unmask = True
c_comment = '''
/*
* QAPI/QMP schema introspection
*
* Copyright (C) 2015 Red Hat, Inc.
*
* This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
* See the COPYING.LIB file in the top-level directory.
*
*/
'''
h_comment = '''
/*
* QAPI/QMP schema introspection
*
* Copyright (C) 2015 Red Hat, Inc.
*
* This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
* See the COPYING.LIB file in the top-level directory.
*
*/
'''
(fdef, fdecl) = open_output(output_dir, do_c, do_h, prefix,
'qmp-introspect.c', 'qmp-introspect.h',
c_comment, h_comment)
fdef.write(mcgen('''
#include "%(prefix)sqmp-introspect.h"
''',
prefix=prefix))
schema = QAPISchema(input_file)
gen = QAPISchemaGenIntrospectVisitor(opt_unmask)
schema.visit(gen)
fdef.write(gen.defn)
fdecl.write(gen.decl)
close_output(fdef, fdecl)