unicorn/qemu/scripts/qapi-event.py
Markus Armbruster a3660e451d
qapi: New QAPISchema intermediate reperesentation
The QAPI code generators work with a syntax tree (nested dictionaries)
plus a few symbol tables (also dictionaries) on the side.

They have clearly outgrown these simple data structures. There's lots
of rummaging around in dictionaries, and information is recomputed on
the fly. For the work I'm going to do, I want more clearly defined
and more convenient interfaces.

Going forward, I also want less coupling between the back-ends and the
syntax tree, to make messing with the syntax easier.

Create a bunch of classes to represent QAPI schemata.

Have the QAPISchema initializer call the parser, then walk the syntax
tree to create the new internal representation, and finally perform
semantic analysis.

Shortcut: the semantic analysis still relies on existing check_exprs()
to do the actual semantic checking. All this code needs to move into
the classes. Mark as TODO.

Simple unions are lowered to flat unions. Flat unions and structs are
represented as a more general object type.

Catching name collisions in generated code would be nice. Mark as
TODO.

We generate array types eagerly, even though most of them aren't used.
Mark as TODO.

Nothing uses the new intermediate representation just yet, thus no
change to generated files.

Backports commit ac88219a6c78302c693fb60fe6cf04358540fbce from qemu
2018-02-19 16:43:30 -05:00

297 lines
7 KiB
Python

#
# QAPI event generator
#
# Copyright (c) 2014 Wenchao Xia
#
# Authors:
# Wenchao Xia <wenchaoqemu@gmail.com>
#
# This work is licensed under the terms of the GNU GPL, version 2.
# See the COPYING file in the top-level directory.
from ordereddict import OrderedDict
from qapi import *
def _generate_event_api_name(event_name, params):
api_name = "void qapi_event_send_%s(" % c_name(event_name).lower();
l = len(api_name)
if params:
for argname, argentry, optional in parse_args(params):
if optional:
api_name += "bool has_%s,\n" % c_name(argname)
api_name += "".ljust(l)
api_name += "%s %s,\n" % (c_type(argentry, is_param=True),
c_name(argname))
api_name += "".ljust(l)
api_name += "Error **errp)"
return api_name;
# Following are the core functions that generate C APIs to emit event.
def generate_event_declaration(api_name):
return mcgen('''
%(api_name)s;
''',
api_name = api_name)
def generate_event_implement(api_name, event_name, params):
# step 1: declare any variables
ret = mcgen("""
%(api_name)s
{
QDict *qmp;
Error *local_err = NULL;
QMPEventFuncEmit emit;
""",
api_name = api_name)
if params:
ret += mcgen("""
QmpOutputVisitor *qov;
Visitor *v;
QObject *obj;
""")
# step 2: check emit function, create a dict
ret += mcgen("""
emit = qmp_event_get_func_emit();
if (!emit) {
return;
}
qmp = qmp_event_build_dict("%(event_name)s");
""",
event_name = event_name)
# step 3: visit the params if params != None
if params:
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, "", "%(event_name)s", 0, &local_err);
if (local_err) {
goto clean;
}
""",
event_name = event_name)
for argname, argentry, optional in parse_args(params):
if optional:
ret += mcgen("""
if (has_%(var)s) {
""",
var = c_name(argname))
push_indent()
if argentry == "str":
var_type = "(char **)"
else:
var_type = ""
ret += mcgen("""
visit_type_%(type)s(v, %(var_type)s&%(var)s, "%(name)s", &local_err);
if (local_err) {
goto clean;
}
""",
var_type = var_type,
var = c_name(argname),
type = type_name(argentry),
name = argname)
if optional:
pop_indent()
ret += mcgen("""
}
""")
ret += mcgen("""
visit_end_struct(v, &local_err);
if (local_err) {
goto clean;
}
obj = qmp_output_get_qobject(qov);
g_assert(obj != NULL);
qdict_put_obj(qmp, "data", obj);
""")
# step 4: call qmp event api
ret += mcgen("""
emit(%(event_enum_value)s, qmp, &local_err);
""",
event_enum_value = event_enum_value)
# step 5: clean up
if params:
ret += mcgen("""
clean:
qmp_output_visitor_cleanup(qov);
""")
ret += mcgen("""
error_propagate(errp, local_err);
QDECREF(qmp);
}
""")
return ret
# Following are the functions that generate an enum type for all defined
# events, similar to qapi-types.py. Here we already have enum name and
# values which were generated before and recorded in event_enum_*. It also
# works around the issue that "import qapi-types" can't work.
def generate_event_enum_decl(event_enum_name, event_enum_values):
lookup_decl = mcgen('''
extern const char *%(event_enum_name)s_lookup[];
''',
event_enum_name = event_enum_name)
enum_decl = mcgen('''
typedef enum %(event_enum_name)s {
''',
event_enum_name = event_enum_name)
# append automatically generated _MAX value
enum_max_value = c_enum_const(event_enum_name, "MAX")
enum_values = event_enum_values + [ enum_max_value ]
i = 0
for value in enum_values:
enum_decl += mcgen('''
%(value)s = %(i)d,
''',
value = value,
i = i)
i += 1
enum_decl += mcgen('''
} %(event_enum_name)s;
''',
event_enum_name = event_enum_name)
return lookup_decl + enum_decl
def generate_event_enum_lookup(event_enum_name, event_enum_strings):
ret = mcgen('''
const char *%(event_enum_name)s_lookup[] = {
''',
event_enum_name = event_enum_name)
for string in event_enum_strings:
ret += mcgen('''
"%(string)s",
''',
string = string)
ret += mcgen('''
NULL,
};
''')
return ret
(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))
exprs = QAPISchema(input_file).get_exprs()
event_enum_name = c_name(prefix + "QAPIEvent", protect=False)
event_enum_values = []
event_enum_strings = []
for expr in exprs:
if expr.has_key('event'):
event_name = expr['event']
params = expr.get('data')
if params and len(params) == 0:
params = None
api_name = _generate_event_api_name(event_name, params)
ret = generate_event_declaration(api_name)
fdecl.write(ret)
# We need an enum value per event
event_enum_value = c_enum_const(event_enum_name, event_name)
ret = generate_event_implement(api_name, event_name, params)
fdef.write(ret)
# Record it, and generate enum later
event_enum_values.append(event_enum_value)
event_enum_strings.append(event_name)
ret = generate_event_enum_decl(event_enum_name, event_enum_values)
fdecl.write(ret)
ret = generate_event_enum_lookup(event_enum_name, event_enum_strings)
fdef.write(ret)
close_output(fdef, fdecl)