qemu-patch-raspberry4/scripts/qapi-event.py
Eric Blake 2c0ef9f411 qapi: Add new visit_free() function
Making each visitor provide its own (awkwardly-named) FOO_cleanup()
is unusual, when we can instead have a polymorphic visit_free()
interface.  Over the next few patches, we can use the polymorphic
functions to eliminate the need for a FOO_get_visitor() function
for accessing specific visitor functionality, once everything can
be accessed directly through the Visitor* interfaces.

The dealloc visitor is the first one converted to completely use
the new entry point, since qapi_dealloc_visitor_cleanup() was the
only reason that qapi_dealloc_get_visitor() existed, and only
generated and testsuite code was even using it.  With the new
visit_free() entry point in place, we no longer need to expose
the QapiDeallocVisitor subtype through qapi_dealloc_visitor_new(),
and can get by with less generated code, with diffs that look like:

| void qapi_free_ACPIOSTInfo(ACPIOSTInfo *obj)
| {
|-    QapiDeallocVisitor *qdv;
|     Visitor *v;
|
|     if (!obj) {
|         return;
|     }
|
|-    qdv = qapi_dealloc_visitor_new();
|-    v = qapi_dealloc_get_visitor(qdv);
|+    v = qapi_dealloc_visitor_new();
|     visit_type_ACPIOSTInfo(v, NULL, &obj, NULL);
|-    qapi_dealloc_visitor_cleanup(qdv);
|+    visit_free(v);
|}

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1465490926-28625-5-git-send-email-eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-07-06 10:52:04 +02:00

217 lines
5.1 KiB
Python

#
# QAPI event generator
#
# Copyright (c) 2014 Wenchao Xia
# Copyright (c) 2015-2016 Red Hat Inc.
#
# Authors:
# Wenchao Xia <wenchaoqemu@gmail.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_event_send_proto(name, arg_type):
return 'void qapi_event_send_%(c_name)s(%(param)s)' % {
'c_name': c_name(name.lower()),
'param': gen_params(arg_type, 'Error **errp')}
def gen_event_send_decl(name, arg_type):
return mcgen('''
%(proto)s;
''',
proto=gen_event_send_proto(name, arg_type))
# Declare and initialize an object 'qapi' using parameters from gen_params()
def gen_param_var(typ):
assert not typ.variants
ret = mcgen('''
%(c_name)s param = {
''',
c_name=typ.c_name())
sep = ' '
for memb in typ.members:
ret += sep
sep = ', '
if memb.optional:
ret += 'has_' + c_name(memb.name) + sep
if memb.type.name == 'str':
# Cast away const added in gen_params()
ret += '(char *)'
ret += c_name(memb.name)
ret += mcgen('''
};
''')
return ret
def gen_event_send(name, arg_type):
# FIXME: Our declaration of local variables (and of 'errp' in the
# parameter list) can collide with exploded members of the event's
# data type passed in as parameters. If this collision ever hits in
# practice, we can rename our local variables with a leading _ prefix,
# or split the code into a wrapper function that creates a boxed
# 'param' object then calls another to do the real work.
ret = mcgen('''
%(proto)s
{
QDict *qmp;
Error *err = NULL;
QMPEventFuncEmit emit;
''',
proto=gen_event_send_proto(name, arg_type))
if arg_type and arg_type.members:
ret += mcgen('''
QmpOutputVisitor *qov;
Visitor *v;
''')
ret += gen_param_var(arg_type)
ret += mcgen('''
emit = qmp_event_get_func_emit();
if (!emit) {
return;
}
qmp = qmp_event_build_dict("%(name)s");
''',
name=name)
if arg_type and arg_type.members:
ret += mcgen('''
qov = qmp_output_visitor_new();
v = qmp_output_get_visitor(qov);
visit_start_struct(v, "%(name)s", NULL, 0, &err);
if (err) {
goto out;
}
visit_type_%(c_name)s_members(v, &param, &err);
if (!err) {
visit_check_struct(v, &err);
}
visit_end_struct(v, NULL);
if (err) {
goto out;
}
qdict_put_obj(qmp, "data", qmp_output_get_qobject(qov));
''',
name=name, c_name=arg_type.c_name())
ret += mcgen('''
emit(%(c_enum)s, qmp, &err);
''',
c_enum=c_enum_const(event_enum_name, name))
if arg_type and arg_type.members:
ret += mcgen('''
out:
visit_free(v);
''')
ret += mcgen('''
error_propagate(errp, err);
QDECREF(qmp);
}
''')
return ret
class QAPISchemaGenEventVisitor(QAPISchemaVisitor):
def __init__(self):
self.decl = None
self.defn = None
self._event_names = None
def visit_begin(self, schema):
self.decl = ''
self.defn = ''
self._event_names = []
def visit_end(self):
self.decl += gen_enum(event_enum_name, self._event_names)
self.defn += gen_enum_lookup(event_enum_name, self._event_names)
self._event_names = None
def visit_event(self, name, info, arg_type):
self.decl += gen_event_send_decl(name, arg_type)
self.defn += gen_event_send(name, arg_type)
self._event_names.append(name)
(input_file, output_dir, do_c, do_h, prefix, dummy) = parse_command_line()
c_comment = '''
/*
* schema-defined QAPI event functions
*
* Copyright (c) 2014 Wenchao Xia
*
* Authors:
* Wenchao Xia <wenchaoqemu@gmail.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 event functions
*
* Copyright (c) 2014 Wenchao Xia
*
* Authors:
* Wenchao Xia <wenchaoqemu@gmail.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-event.c', 'qapi-event.h',
c_comment, h_comment)
fdef.write(mcgen('''
#include "qemu/osdep.h"
#include "qemu-common.h"
#include "%(prefix)sqapi-event.h"
#include "%(prefix)sqapi-visit.h"
#include "qapi/qmp-output-visitor.h"
#include "qapi/qmp-event.h"
''',
prefix=prefix))
fdecl.write(mcgen('''
#include "qapi/error.h"
#include "qapi/qmp/qdict.h"
#include "%(prefix)sqapi-types.h"
''',
prefix=prefix))
event_enum_name = c_name(prefix + "QAPIEvent", protect=False)
schema = QAPISchema(input_file)
gen = QAPISchemaGenEventVisitor()
schema.visit(gen)
fdef.write(gen.defn)
fdecl.write(gen.decl)
close_output(fdef, fdecl)