qemu/scripts/qapi-types.py

344 lines
8.9 KiB
Python

#
# QAPI types generator
#
# Copyright IBM, Corp. 2011
# Copyright (c) 2013-2015 Red Hat Inc.
#
# Authors:
# Anthony Liguori <aliguori@us.ibm.com>
# 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 *
def gen_fwd_object_or_array(name):
return mcgen('''
typedef struct %(c_name)s %(c_name)s;
''',
c_name=c_name(name))
def gen_array(name, element_type):
return mcgen('''
struct %(c_name)s {
union {
%(c_type)s value;
uint64_t padding;
};
%(c_name)s *next;
};
''',
c_name=c_name(name), c_type=element_type.c_type())
def gen_struct_field(name, typ, optional):
ret = ''
if optional:
ret += mcgen('''
bool has_%(c_name)s;
''',
c_name=c_name(name))
ret += mcgen('''
%(c_type)s %(c_name)s;
''',
c_type=typ.c_type(), c_name=c_name(name))
return ret
def gen_struct_fields(members):
ret = ''
for memb in members:
ret += gen_struct_field(memb.name, memb.type, memb.optional)
return ret
def gen_struct(name, base, members):
ret = mcgen('''
struct %(c_name)s {
''',
c_name=c_name(name))
if base:
ret += gen_struct_field('base', base, False)
ret += gen_struct_fields(members)
# Make sure that all structs have at least one field; this avoids
# potential issues with attempting to malloc space for zero-length
# structs in C, and also incompatibility with C++ (where an empty
# struct is size 1).
if not base and not members:
ret += mcgen('''
char qapi_dummy_field_for_empty_struct;
''')
ret += mcgen('''
};
''')
return ret
def gen_alternate_qtypes_decl(name):
return mcgen('''
extern const int %(c_name)s_qtypes[];
''',
c_name=c_name(name))
def gen_alternate_qtypes(name, variants):
ret = mcgen('''
const int %(c_name)s_qtypes[QTYPE_MAX] = {
''',
c_name=c_name(name))
for var in variants.variants:
qtype = var.type.alternate_qtype()
assert qtype
ret += mcgen('''
[%(qtype)s] = %(enum_const)s,
''',
qtype=qtype,
enum_const=c_enum_const(variants.tag_member.type.name,
var.name))
ret += mcgen('''
};
''')
return ret
def gen_union(name, base, variants):
ret = mcgen('''
struct %(c_name)s {
''',
c_name=c_name(name))
if base:
ret += mcgen('''
/* Members inherited from %(c_name)s: */
''',
c_name=c_name(base.name))
ret += gen_struct_fields(base.members)
ret += mcgen('''
/* Own members: */
''')
else:
ret += mcgen('''
%(c_type)s kind;
''',
c_type=c_name(variants.tag_member.type.name))
# FIXME: What purpose does data serve, besides preventing a union that
# has a branch named 'data'? We use it in qapi-visit.py to decide
# whether to bypass the switch statement if visiting the discriminator
# failed; but since we 0-initialize structs, and cannot tell what
# branch of the union is in use if the discriminator is invalid, there
# should not be any data leaks even without a data pointer. Or, if
# 'data' is merely added to guarantee we don't have an empty union,
# shouldn't we enforce that at .json parse time?
ret += mcgen('''
union { /* union tag is @%(c_name)s */
void *data;
''',
# TODO ugly special case for simple union
# Use same tag name in C as on the wire to get rid of
# it, then: c_name=c_name(variants.tag_member.name)
c_name=c_name(variants.tag_name or 'kind'))
for var in variants.variants:
# Ugly special case for simple union TODO get rid of it
typ = var.simple_union_type() or var.type
ret += mcgen('''
%(c_type)s %(c_name)s;
''',
c_type=typ.c_type(),
c_name=c_name(var.name))
ret += mcgen('''
};
};
''')
return ret
def gen_type_cleanup_decl(name):
ret = mcgen('''
void qapi_free_%(c_name)s(%(c_name)s *obj);
''',
c_name=c_name(name))
return ret
def gen_type_cleanup(name):
ret = mcgen('''
void qapi_free_%(c_name)s(%(c_name)s *obj)
{
QapiDeallocVisitor *qdv;
Visitor *v;
if (!obj) {
return;
}
qdv = qapi_dealloc_visitor_new();
v = qapi_dealloc_get_visitor(qdv);
visit_type_%(c_name)s(v, &obj, NULL, NULL);
qapi_dealloc_visitor_cleanup(qdv);
}
''',
c_name=c_name(name))
return ret
class QAPISchemaGenTypeVisitor(QAPISchemaVisitor):
def __init__(self):
self.decl = None
self.defn = None
self._fwdecl = None
self._fwdefn = None
self._btin = None
def visit_begin(self, schema):
self.decl = ''
self.defn = ''
self._fwdecl = ''
self._fwdefn = ''
self._btin = guardstart('QAPI_TYPES_BUILTIN')
def visit_end(self):
self.decl = self._fwdecl + self.decl
self._fwdecl = None
self.defn = self._fwdefn + self.defn
self._fwdefn = None
# To avoid header dependency hell, we always generate
# declarations for built-in types in our header files and
# simply guard them. See also do_builtins (command line
# option -b).
self._btin += guardend('QAPI_TYPES_BUILTIN')
self.decl = self._btin + self.decl
self._btin = None
def visit_needed(self, entity):
# Visit everything except implicit objects
return not (entity.is_implicit() and
isinstance(entity, QAPISchemaObjectType))
def _gen_type_cleanup(self, name):
self.decl += gen_type_cleanup_decl(name)
self.defn += gen_type_cleanup(name)
def visit_enum_type(self, name, info, values, prefix):
self._fwdecl += gen_enum(name, values, prefix)
self._fwdefn += gen_enum_lookup(name, values, prefix)
def visit_array_type(self, name, info, element_type):
if isinstance(element_type, QAPISchemaBuiltinType):
self._btin += gen_fwd_object_or_array(name)
self._btin += gen_array(name, element_type)
self._btin += gen_type_cleanup_decl(name)
if do_builtins:
self.defn += gen_type_cleanup(name)
else:
self._fwdecl += gen_fwd_object_or_array(name)
self.decl += gen_array(name, element_type)
self._gen_type_cleanup(name)
def visit_object_type(self, name, info, base, members, variants):
self._fwdecl += gen_fwd_object_or_array(name)
if variants:
assert not members # not implemented
self.decl += gen_union(name, base, variants)
else:
self.decl += gen_struct(name, base, members)
self._gen_type_cleanup(name)
def visit_alternate_type(self, name, info, variants):
self._fwdecl += gen_fwd_object_or_array(name)
self._fwdefn += gen_alternate_qtypes(name, variants)
self.decl += gen_union(name, None, variants)
self.decl += gen_alternate_qtypes_decl(name)
self._gen_type_cleanup(name)
# If you link code generated from multiple schemata, you want only one
# instance of the code for built-in types. Generate it only when
# do_builtins, enabled by command line option -b. See also
# QAPISchemaGenTypeVisitor.visit_end().
do_builtins = False
(input_file, output_dir, do_c, do_h, prefix, opts) = \
parse_command_line("b", ["builtins"])
for o, a in opts:
if o in ("-b", "--builtins"):
do_builtins = True
c_comment = '''
/*
* deallocation functions for schema-defined QAPI types
*
* Copyright IBM, Corp. 2011
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.com>
* Michael Roth <mdroth@linux.vnet.ibm.com>
*
* 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 = '''
/*
* schema-defined QAPI types
*
* Copyright IBM, Corp. 2011
*
* Authors:
* Anthony Liguori <aliguori@us.ibm.com>
*
* 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,
'qapi-types.c', 'qapi-types.h',
c_comment, h_comment)
fdef.write(mcgen('''
#include "qapi/dealloc-visitor.h"
#include "%(prefix)sqapi-types.h"
#include "%(prefix)sqapi-visit.h"
''',
prefix=prefix))
fdecl.write(mcgen('''
#include <stdbool.h>
#include <stdint.h>
#include "qapi/qmp/qobject.h"
'''))
schema = QAPISchema(input_file)
gen = QAPISchemaGenTypeVisitor()
schema.visit(gen)
fdef.write(gen.defn)
fdecl.write(gen.decl)
close_output(fdef, fdecl)