unicorn/qemu/scripts/qapi-visit.py
Eric Blake 1f54314cbb
qapi: Drop unused 'kind' for struct/enum visit
visit_start_struct() and visit_type_enum() had a 'kind' argument
that was usually set to either the stringized version of the
corresponding qapi type name, or to NULL (although some clients
didn't even get that right). But nothing ever used the argument.
It's even hard to argue that it would be useful in a debugger,
as a stack backtrace also tells which type is being visited.

Therefore, drop the 'kind' argument as dead.

Backports commit 337283dffbb5ad5860ed00408a5fd0665c21be07 from qemu
2018-02-19 23:43:54 -05:00

461 lines
12 KiB
Python

#
# QAPI visitor generator
#
# Copyright IBM, Corp. 2011
# Copyright (C) 2014-2016 Red Hat, Inc.
#
# Authors:
# Anthony Liguori <aliguori@us.ibm.com>
# Michael Roth <mdroth@linux.vnet.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 *
import re
# visit_type_FOO_implicit() is emitted as needed; track if it has already
# been output.
implicit_structs_seen = set()
# visit_type_FOO_fields() is always emitted; track if a forward declaration
# or implementation has already been output.
struct_fields_seen = set()
def gen_visit_decl(name, scalar=False):
c_type = c_name(name) + ' *'
if not scalar:
c_type += '*'
return mcgen('''
void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_type)sobj, Error **errp);
''',
c_name=c_name(name), c_type=c_type)
def gen_visit_fields_decl(typ):
ret = ''
if typ.name not in struct_fields_seen:
ret += mcgen('''
static void visit_type_%(c_type)s_fields(Visitor *v, %(c_type)s **obj, Error **errp);
''',
c_type=typ.c_name())
struct_fields_seen.add(typ.name)
return ret
def gen_visit_implicit_struct(typ):
if typ in implicit_structs_seen:
return ''
implicit_structs_seen.add(typ)
ret = gen_visit_fields_decl(typ)
ret += mcgen('''
static void visit_type_implicit_%(c_type)s(Visitor *v, %(c_type)s **obj, Error **errp)
{
Error *err = NULL;
visit_start_implicit_struct(v, (void **)obj, sizeof(%(c_type)s), &err);
if (!err) {
visit_type_%(c_type)s_fields(v, obj, errp);
visit_end_implicit_struct(v);
}
error_propagate(errp, err);
}
''',
c_type=typ.c_name())
return ret
def gen_visit_struct_fields(name, base, members):
ret = ''
if base:
ret += gen_visit_fields_decl(base)
struct_fields_seen.add(name)
ret += mcgen('''
static void visit_type_%(c_name)s_fields(Visitor *v, %(c_name)s **obj, Error **errp)
{
Error *err = NULL;
''',
c_name=c_name(name))
if base:
ret += mcgen('''
visit_type_%(c_type)s_fields(v, (%(c_type)s **)obj, &err);
''',
c_type=base.c_name())
ret += gen_err_check()
ret += gen_visit_fields(members, prefix='(*obj)->')
# 'goto out' produced for base, and by gen_visit_fields() for each member
if base or members:
ret += mcgen('''
out:
''')
ret += mcgen('''
error_propagate(errp, err);
}
''')
return ret
def gen_visit_struct(name, base, members):
ret = gen_visit_struct_fields(name, base, members)
# FIXME: if *obj is NULL on entry, and visit_start_struct() assigns to
# *obj, but then visit_type_FOO_fields() fails, we should clean up *obj
# rather than leaving it non-NULL. As currently written, the caller must
# call qapi_free_FOO() to avoid a memory leak of the partial FOO.
ret += mcgen('''
void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s **obj, Error **errp)
{
Error *err = NULL;
visit_start_struct(v, name, (void **)obj, sizeof(%(c_name)s), &err);
if (err) {
goto out;
}
if (!*obj) {
goto out_obj;
}
visit_type_%(c_name)s_fields(v, obj, &err);
error_propagate(errp, err);
err = NULL;
out_obj:
visit_end_struct(v, &err);
out:
error_propagate(errp, err);
}
''',
c_name=c_name(name))
return ret
def gen_visit_list(name, element_type):
# FIXME: if *obj is NULL on entry, and the first visit_next_list()
# assigns to *obj, while a later one fails, we should clean up *obj
# rather than leaving it non-NULL. As currently written, the caller must
# call qapi_free_FOOList() to avoid a memory leak of the partial FOOList.
return mcgen('''
void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s **obj, Error **errp)
{
Error *err = NULL;
GenericList *i, **prev;
visit_start_list(v, name, &err);
if (err) {
goto out;
}
for (prev = (GenericList **)obj;
!err && (i = visit_next_list(v, prev)) != NULL;
prev = &i) {
%(c_name)s *native_i = (%(c_name)s *)i;
visit_type_%(c_elt_type)s(v, NULL, &native_i->value, &err);
}
error_propagate(errp, err);
err = NULL;
visit_end_list(v);
out:
error_propagate(errp, err);
}
''',
c_name=c_name(name), c_elt_type=element_type.c_name())
def gen_visit_enum(name):
return mcgen('''
void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s *obj, Error **errp)
{
int value = *obj;
visit_type_enum(v, name, &value, %(c_name)s_lookup, errp);
*obj = value;
}
''',
c_name=c_name(name))
def gen_visit_alternate(name, variants):
promote_int = 'true'
for var in variants.variants:
if var.type.alternate_qtype() == 'QTYPE_QINT':
promote_int = 'false'
ret = mcgen('''
void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s **obj, Error **errp)
{
Error *err = NULL;
visit_start_implicit_struct(v, (void**) obj, sizeof(%(c_name)s), &err);
if (err) {
goto out;
}
visit_get_next_type(v, name, &(*obj)->type, %(promote_int)s, &err);
if (err) {
goto out_obj;
}
switch ((*obj)->type) {
''',
c_name=c_name(name), promote_int=promote_int)
for var in variants.variants:
ret += mcgen('''
case %(case)s:
visit_type_%(c_type)s(v, name, &(*obj)->u.%(c_name)s, &err);
break;
''',
case=var.type.alternate_qtype(),
c_type=var.type.c_name(),
c_name=c_name(var.name))
ret += mcgen('''
default:
error_setg(&err, QERR_INVALID_PARAMETER_TYPE, name ? name : "null",
"%(name)s");
}
out_obj:
error_propagate(errp, err);
err = NULL;
visit_end_implicit_struct(v);
out:
error_propagate(errp, err);
}
''',
name=name)
return ret
def gen_visit_union(name, base, variants):
ret = ''
if base:
ret += gen_visit_fields_decl(base)
for var in variants.variants:
# Ugly special case for simple union TODO get rid of it
if not var.simple_union_type():
ret += gen_visit_implicit_struct(var.type)
ret += mcgen('''
void visit_type_%(c_name)s(Visitor *v, const char *name, %(c_name)s **obj, Error **errp)
{
Error *err = NULL;
visit_start_struct(v, name, (void **)obj, sizeof(%(c_name)s), &err);
if (err) {
goto out;
}
if (!*obj) {
goto out_obj;
}
''',
c_name=c_name(name))
if base:
ret += mcgen('''
visit_type_%(c_name)s_fields(v, (%(c_name)s **)obj, &err);
''',
c_name=base.c_name())
else:
ret += mcgen('''
visit_type_%(c_type)s(v, "%(name)s", &(*obj)->%(c_name)s, &err);
''',
c_type=variants.tag_member.type.c_name(),
c_name=c_name(variants.tag_member.name),
name=variants.tag_member.name)
ret += gen_err_check(label='out_obj')
ret += mcgen('''
if (!visit_start_union(v, !!(*obj)->u.data, &err) || err) {
goto out_obj;
}
switch ((*obj)->%(c_name)s) {
''',
c_name=c_name(variants.tag_member.name))
for var in variants.variants:
# TODO ugly special case for simple union
simple_union_type = var.simple_union_type()
ret += mcgen('''
case %(case)s:
''',
case=c_enum_const(variants.tag_member.type.name,
var.name))
if simple_union_type:
ret += mcgen('''
visit_type_%(c_type)s(v, "data", &(*obj)->u.%(c_name)s, &err);
''',
c_type=simple_union_type.c_name(),
c_name=c_name(var.name))
else:
ret += mcgen('''
visit_type_implicit_%(c_type)s(v, &(*obj)->u.%(c_name)s, &err);
''',
c_type=var.type.c_name(),
c_name=c_name(var.name))
ret += mcgen('''
break;
''')
ret += mcgen('''
default:
abort();
}
out_obj:
error_propagate(errp, err);
err = NULL;
visit_end_struct(v, &err);
out:
error_propagate(errp, err);
}
''')
return ret
class QAPISchemaGenVisitVisitor(QAPISchemaVisitor):
def __init__(self):
self.decl = None
self.defn = None
self._btin = None
def visit_begin(self, schema):
self.decl = ''
self.defn = ''
self._btin = guardstart('QAPI_VISIT_BUILTIN')
def visit_end(self):
# 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_VISIT_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 visit_enum_type(self, name, info, values, prefix):
# Special case for our lone builtin enum type
# TODO use something cleaner than existence of info
if not info:
self._btin += gen_visit_decl(name, scalar=True)
if do_builtins:
self.defn += gen_visit_enum(name)
else:
self.decl += gen_visit_decl(name, scalar=True)
self.defn += gen_visit_enum(name)
def visit_array_type(self, name, info, element_type):
decl = gen_visit_decl(name)
defn = gen_visit_list(name, element_type)
if isinstance(element_type, QAPISchemaBuiltinType):
self._btin += decl
if do_builtins:
self.defn += defn
else:
self.decl += decl
self.defn += defn
def visit_object_type(self, name, info, base, members, variants):
self.decl += gen_visit_decl(name)
if variants:
if members:
# Members other than variants.tag_member not implemented
assert len(members) == 1
assert members[0] == variants.tag_member
self.defn += gen_visit_union(name, base, variants)
else:
self.defn += gen_visit_struct(name, base, members)
def visit_alternate_type(self, name, info, variants):
self.decl += gen_visit_decl(name)
self.defn += gen_visit_alternate(name, variants)
# 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
# QAPISchemaGenVisitVisitor.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 = '''
/*
* schema-defined QAPI visitor functions
*
* 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.
*
*/
'''
h_comment = '''
/*
* schema-defined QAPI visitor functions
*
* 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-visit.c', 'qapi-visit.h',
c_comment, h_comment)
fdef.write(mcgen('''
#include "qemu-common.h"
#include "%(prefix)sqapi-visit.h"
''',
prefix=prefix))
fdecl.write(mcgen('''
#include "qapi/visitor.h"
#include "qapi/qmp/qerror.h"
#include "%(prefix)sqapi-types.h"
''',
prefix=prefix))
schema = QAPISchema(input_file)
gen = QAPISchemaGenVisitVisitor()
schema.visit(gen)
fdef.write(gen.defn)
fdecl.write(gen.decl)
close_output(fdef, fdecl)