qemu/scripts/qapi-visit.py
Paolo Bonzini 3a86a0fa76 qapi: untangle next_list
Right now, the semantics of next_list are complicated.  The caller must:

* call start_list

* call next_list for each element *including the first*

* on the first call to next_list, the second argument should point to
NULL and the result is the head of the list.  On subsequent calls,
the second argument should point to the last node (last result of
next_list) and next_list itself tacks the element at the tail of the
list.

This works for both input and output visitor, but having the visitor
write memory when it is only reading the list is ugly.  Plus, relying
on *list to detect the first call is tricky and undocumented.

We can initialize so->entry in next_list instead of start_list, leaving
it NULL in start_list.  This way next_list sees clearly whether it is
on the first call---as a bonus, it discriminates the cases based on
internal state of the visitor rather than external state.  We can
also pull the assignment of the list head from generated code up to
next_list.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2012-03-27 09:14:19 -03:00

311 lines
7.5 KiB
Python

#
# QAPI visitor generator
#
# Copyright IBM, Corp. 2011
#
# Authors:
# Anthony Liguori <aliguori@us.ibm.com>
# Michael Roth <mdroth@linux.vnet.ibm.com>
#
# This work is licensed under the terms of the GNU GPLv2.
# See the COPYING.LIB file in the top-level directory.
from ordereddict import OrderedDict
from qapi import *
import sys
import os
import getopt
import errno
def generate_visit_struct_body(field_prefix, members):
ret = ""
if len(field_prefix):
field_prefix = field_prefix + "."
for argname, argentry, optional, structured in parse_args(members):
if optional:
ret += mcgen('''
visit_start_optional(m, (obj && *obj) ? &(*obj)->%(c_prefix)shas_%(c_name)s : NULL, "%(name)s", errp);
if ((*obj)->%(prefix)shas_%(c_name)s) {
''',
c_prefix=c_var(field_prefix), prefix=field_prefix,
c_name=c_var(argname), name=argname)
push_indent()
if structured:
ret += mcgen('''
visit_start_struct(m, NULL, "", "%(name)s", 0, errp);
''',
name=argname)
ret += generate_visit_struct_body(field_prefix + argname, argentry)
ret += mcgen('''
visit_end_struct(m, errp);
''')
else:
ret += mcgen('''
visit_type_%(type)s(m, (obj && *obj) ? &(*obj)->%(c_prefix)s%(c_name)s : NULL, "%(name)s", errp);
''',
c_prefix=c_var(field_prefix), prefix=field_prefix,
type=type_name(argentry), c_name=c_var(argname),
name=argname)
if optional:
pop_indent()
ret += mcgen('''
}
visit_end_optional(m, errp);
''')
return ret
def generate_visit_struct(name, members):
ret = mcgen('''
void visit_type_%(name)s(Visitor *m, %(name)s ** obj, const char *name, Error **errp)
{
if (error_is_set(errp)) {
return;
}
visit_start_struct(m, (void **)obj, "%(name)s", name, sizeof(%(name)s), errp);
if (obj && !*obj) {
goto end;
}
''',
name=name)
push_indent()
ret += generate_visit_struct_body("", members)
pop_indent()
ret += mcgen('''
end:
visit_end_struct(m, errp);
}
''')
return ret
def generate_visit_list(name, members):
return mcgen('''
void visit_type_%(name)sList(Visitor *m, %(name)sList ** obj, const char *name, Error **errp)
{
GenericList *i, **prev = (GenericList **)obj;
if (error_is_set(errp)) {
return;
}
visit_start_list(m, name, errp);
for (; (i = visit_next_list(m, prev, errp)) != NULL; prev = &i) {
%(name)sList *native_i = (%(name)sList *)i;
visit_type_%(name)s(m, &native_i->value, NULL, errp);
}
visit_end_list(m, errp);
}
''',
name=name)
def generate_visit_enum(name, members):
return mcgen('''
void visit_type_%(name)s(Visitor *m, %(name)s * obj, const char *name, Error **errp)
{
visit_type_enum(m, (int *)obj, %(name)s_lookup, "%(name)s", name, errp);
}
''',
name=name)
def generate_visit_union(name, members):
ret = generate_visit_enum('%sKind' % name, members.keys())
ret += mcgen('''
void visit_type_%(name)s(Visitor *m, %(name)s ** obj, const char *name, Error **errp)
{
Error *err = NULL;
if (error_is_set(errp)) {
return;
}
visit_start_struct(m, (void **)obj, "%(name)s", name, sizeof(%(name)s), &err);
if (obj && !*obj) {
goto end;
}
visit_type_%(name)sKind(m, &(*obj)->kind, "type", &err);
if (err) {
error_propagate(errp, err);
goto end;
}
switch ((*obj)->kind) {
''',
name=name)
for key in members:
ret += mcgen('''
case %(abbrev)s_KIND_%(enum)s:
visit_type_%(c_type)s(m, &(*obj)->%(c_name)s, "data", errp);
break;
''',
abbrev = de_camel_case(name).upper(),
enum = c_fun(de_camel_case(key)).upper(),
c_type=members[key],
c_name=c_fun(key))
ret += mcgen('''
default:
abort();
}
end:
visit_end_struct(m, errp);
}
''')
return ret
def generate_declaration(name, members, genlist=True):
ret = mcgen('''
void visit_type_%(name)s(Visitor *m, %(name)s ** obj, const char *name, Error **errp);
''',
name=name)
if genlist:
ret += mcgen('''
void visit_type_%(name)sList(Visitor *m, %(name)sList ** obj, const char *name, Error **errp);
''',
name=name)
return ret
def generate_decl_enum(name, members, genlist=True):
return mcgen('''
void visit_type_%(name)s(Visitor *m, %(name)s * obj, const char *name, Error **errp);
''',
name=name)
try:
opts, args = getopt.gnu_getopt(sys.argv[1:], "chp:o:",
["source", "header", "prefix=", "output-dir="])
except getopt.GetoptError, err:
print str(err)
sys.exit(1)
output_dir = ""
prefix = ""
c_file = 'qapi-visit.c'
h_file = 'qapi-visit.h'
do_c = False
do_h = False
for o, a in opts:
if o in ("-p", "--prefix"):
prefix = a
elif o in ("-o", "--output-dir"):
output_dir = a + "/"
elif o in ("-c", "--source"):
do_c = True
elif o in ("-h", "--header"):
do_h = True
if not do_c and not do_h:
do_c = True
do_h = True
c_file = output_dir + prefix + c_file
h_file = output_dir + prefix + h_file
try:
os.makedirs(output_dir)
except os.error, e:
if e.errno != errno.EEXIST:
raise
def maybe_open(really, name, opt):
if really:
return open(name, opt)
else:
import StringIO
return StringIO.StringIO()
fdef = maybe_open(do_c, c_file, 'w')
fdecl = maybe_open(do_h, h_file, 'w')
fdef.write(mcgen('''
/* THIS FILE IS AUTOMATICALLY GENERATED, DO NOT MODIFY */
/*
* 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.
*
*/
#include "%(header)s"
''',
header=basename(h_file)))
fdecl.write(mcgen('''
/* THIS FILE IS AUTOMATICALLY GENERATED, DO NOT MODIFY */
/*
* schema-defined QAPI visitor function
*
* 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.
*
*/
#ifndef %(guard)s
#define %(guard)s
#include "qapi/qapi-visit-core.h"
#include "%(prefix)sqapi-types.h"
''',
prefix=prefix, guard=guardname(h_file)))
exprs = parse_schema(sys.stdin)
for expr in exprs:
if expr.has_key('type'):
ret = generate_visit_struct(expr['type'], expr['data'])
ret += generate_visit_list(expr['type'], expr['data'])
fdef.write(ret)
ret = generate_declaration(expr['type'], expr['data'])
fdecl.write(ret)
elif expr.has_key('union'):
ret = generate_visit_union(expr['union'], expr['data'])
ret += generate_visit_list(expr['union'], expr['data'])
fdef.write(ret)
ret = generate_decl_enum('%sKind' % expr['union'], expr['data'].keys())
ret += generate_declaration(expr['union'], expr['data'])
fdecl.write(ret)
elif expr.has_key('enum'):
ret = generate_visit_enum(expr['enum'], expr['data'])
fdef.write(ret)
ret = generate_decl_enum(expr['enum'], expr['data'])
fdecl.write(ret)
fdecl.write('''
#endif
''')
fdecl.flush()
fdecl.close()
fdef.flush()
fdef.close()