For a simple union SU, gen_visit_union() generates a visit of its
single tag member, like this:
visit_type_SUKind(v, "type", &(*obj)->type, &err);
For a flat union FU with base B, it generates a visit of its base
fields:
visit_type_B_fields(v, (B **)obj, &err);
Instead, we can simply visit the common members using the same fields
visit function we use for structs, generated with
gen_visit_struct_fields(). This function visits the base if any, then
the local members.
For a simple union SU, visit_type_SU_fields() contains exactly the old
tag member visit, because there is no base, and the tag member is the
only member. For instance, the code generated for qapi-schema.json's
KeyValue changes like this:
+static void visit_type_KeyValue_fields(Visitor *v, KeyValue **obj, Error **errp)
+{
+ Error *err = NULL;
+
+ visit_type_KeyValueKind(v, "type", &(*obj)->type, &err);
+ if (err) {
+ goto out;
+ }
+
+out:
+ error_propagate(errp, err);
+}
+
void visit_type_KeyValue(Visitor *v, const char *name, KeyValue **obj, Error **errp)
{
Error *err = NULL;
@@ -4863,7 +4911,7 @@ void visit_type_KeyValue(Visitor *v, con
if (!*obj) {
goto out_obj;
}
- visit_type_KeyValueKind(v, "type", &(*obj)->type, &err);
+ visit_type_KeyValue_fields(v, obj, &err);
if (err) {
goto out_obj;
}
For a flat union FU, visit_type_FU_fields() contains exactly the old
base fields visit, because there is a base, but no members. For
instance, the code generated for qapi-schema.json's CpuInfo changes
like this:
static void visit_type_CpuInfoBase_fields(Visitor *v, CpuInfoBase **obj, Error **errp);
+static void visit_type_CpuInfo_fields(Visitor *v, CpuInfo **obj, Error **errp)
+{
+ Error *err = NULL;
+
+ visit_type_CpuInfoBase_fields(v, (CpuInfoBase **)obj, &err);
+ if (err) {
+ goto out;
+ }
+
+out:
+ error_propagate(errp, err);
+}
+
static void visit_type_CpuInfoX86_fields(Visitor *v, CpuInfoX86 **obj, Error **errp)
...
@@ -3485,7 +3509,7 @@ void visit_type_CpuInfo(Visitor *v, cons
if (!*obj) {
goto out_obj;
}
- visit_type_CpuInfoBase_fields(v, (CpuInfoBase **)obj, &err);
+ visit_type_CpuInfo_fields(v, obj, &err);
if (err) {
goto out_obj;
}
As you see, the generated code grows a bit, but in practice, it's lost
in the noise: qapi-schema.json's qapi-visit.c gains roughly 1%.
This simplification became possible with commit 441cbac
"qapi-visit:
Convert to QAPISchemaVisitor, fixing bugs". It's a step towards
unifying gen_struct() and gen_union().
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1453902888-20457-2-git-send-email-armbru@redhat.com>
[improve commit message examples]
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1455778109-6278-6-git-send-email-eblake@redhat.com>
[Commit message tweaked]
441 lines
12 KiB
Python
441 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);
|
|
}
|
|
|
|
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:
|
|
visit_end_implicit_struct(v);
|
|
out:
|
|
error_propagate(errp, err);
|
|
}
|
|
''',
|
|
name=name)
|
|
|
|
return ret
|
|
|
|
|
|
def gen_visit_union(name, base, members, variants):
|
|
ret = gen_visit_struct_fields(name, base, members)
|
|
|
|
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;
|
|
}
|
|
visit_type_%(c_name)s_fields(v, obj, &err);
|
|
''',
|
|
c_name=c_name(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,
|
|
variants.tag_member.type.prefix))
|
|
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:
|
|
self.defn += gen_visit_union(name, base, members, 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/osdep.h"
|
|
#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)
|