unicorn/qemu/scripts/qapi-event.py
Eric Blake 13b3a6c92f
qapi: Consistent generated code: minimize push_indent() usage
We had some pointless differences in the generated code for visit,
command marshalling, and events; unifying them makes it easier for
future patches to consolidate to common helper functions.
This is one patch of a series to clean up these differences.

This patch reduces the number of push_indent()/pop_indent() pairs
so that generated code is typically already at its natural output
indentation in the python files. It is easier to reason about
generated code if the reader does not have to track how much
spacing will be inserted alongside the code, and moreso when all
of the generators use the same patterns (qapi-type and qapi-event
were already using in-place indentation).

Arguably, the resulting python may be a bit harder to read with C
code at the same indentation as python; on the other hand, not
having to think about push_indent() is a win, and most decent
editors provide syntax highlighting that makes it easier to
visually distinguish python code from string literals that will
become C code.

There is no change to the generated output.

Backports commit 05372f708a8cb3556e4d67458de79417dadf241f from qemu
2018-02-19 18:38:48 -05:00

216 lines
4.9 KiB
Python

#
# QAPI event generator
#
# Copyright (c) 2014 Wenchao Xia
# Copyright (c) 2015 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))
def gen_event_send(name, arg_type):
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;
QObject *obj;
''')
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();
g_assert(qov);
v = qmp_output_get_visitor(qov);
g_assert(v);
/* Fake visit, as if all members are under a structure */
visit_start_struct(v, NULL, "", "%(name)s", 0, &err);
''',
name=name)
ret += gen_err_check()
for memb in arg_type.members:
if memb.optional:
ret += mcgen('''
if (has_%(c_name)s) {
''',
c_name=c_name(memb.name))
push_indent()
# Ugly: need to cast away the const
if memb.type.name == "str":
cast = '(char **)'
else:
cast = ''
ret += mcgen('''
visit_type_%(c_type)s(v, %(cast)s&%(c_name)s, "%(name)s", &err);
''',
cast=cast,
c_name=c_name(memb.name),
c_type=memb.type.c_name(),
name=memb.name)
ret += gen_err_check()
if memb.optional:
pop_indent()
ret += mcgen('''
}
''')
ret += mcgen('''
visit_end_struct(v, &err);
if (err) {
goto out;
}
obj = qmp_output_get_qobject(qov);
g_assert(obj != NULL);
qdict_put_obj(qmp, "data", obj);
''')
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:
qmp_output_visitor_cleanup(qov);
''')
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-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)