qemu/scripts/qapi-types.py
Michael Roth a678e26cbe qapi: pad GenericList value fields to 64 bits
With the introduction of native list types, we now have types such as
int64List where the 'value' field is not a pointer, but the actual
64-bit value.

On 32-bit architectures, this can lead to situations where 'next' field
offset in GenericList does not correspond to the 'next' field in the
types that we cast to GenericList when using the visit_next_list()
interface, causing issues when we attempt to traverse linked list
structures of these types.

To fix this, pad the 'value' field of GenericList and other
schema-defined/native *List types out to 64-bits.

This is less memory-efficient for 32-bit architectures, but allows us to
continue to rely on list-handling interfaces that target GenericList to
simply visitor implementations.

In the future we can improve efficiency by defaulting to using native C
array backends to handle list of non-pointer types, which would be more
memory efficient in itself and allow us to roll back this change.

Signed-off-by: Michael Roth <mdroth@linux.vnet.ibm.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2013-05-30 09:08:38 -04:00

376 lines
8.8 KiB
Python

#
# QAPI types generator
#
# Copyright IBM, Corp. 2011
#
# Authors:
# Anthony Liguori <aliguori@us.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_fwd_struct(name, members, builtin_type=False):
if builtin_type:
return mcgen('''
typedef struct %(name)sList
{
union {
%(type)s value;
uint64_t padding;
};
struct %(name)sList *next;
} %(name)sList;
''',
type=c_type(name),
name=name)
return mcgen('''
typedef struct %(name)s %(name)s;
typedef struct %(name)sList
{
union {
%(name)s *value;
uint64_t padding;
};
struct %(name)sList *next;
} %(name)sList;
''',
name=name)
def generate_fwd_enum_struct(name, members):
return mcgen('''
typedef struct %(name)sList
{
%(name)s value;
struct %(name)sList *next;
} %(name)sList;
''',
name=name)
def generate_struct(structname, fieldname, members):
ret = mcgen('''
struct %(name)s
{
''',
name=structname)
for argname, argentry, optional, structured in parse_args(members):
if optional:
ret += mcgen('''
bool has_%(c_name)s;
''',
c_name=c_var(argname))
if structured:
push_indent()
ret += generate_struct("", argname, argentry)
pop_indent()
else:
ret += mcgen('''
%(c_type)s %(c_name)s;
''',
c_type=c_type(argentry), c_name=c_var(argname))
if len(fieldname):
fieldname = " " + fieldname
ret += mcgen('''
}%(field)s;
''',
field=fieldname)
return ret
def generate_enum_lookup(name, values):
ret = mcgen('''
const char *%(name)s_lookup[] = {
''',
name=name)
i = 0
for value in values:
ret += mcgen('''
"%(value)s",
''',
value=value)
ret += mcgen('''
NULL,
};
''')
return ret
def generate_enum_name(name):
if name.isupper():
return c_fun(name, False)
new_name = ''
for c in c_fun(name, False):
if c.isupper():
new_name += '_'
new_name += c
return new_name.lstrip('_').upper()
def generate_enum(name, values):
lookup_decl = mcgen('''
extern const char *%(name)s_lookup[];
''',
name=name)
enum_decl = mcgen('''
typedef enum %(name)s
{
''',
name=name)
# append automatically generated _MAX value
enum_values = values + [ 'MAX' ]
i = 0
for value in enum_values:
enum_decl += mcgen('''
%(abbrev)s_%(value)s = %(i)d,
''',
abbrev=de_camel_case(name).upper(),
value=generate_enum_name(value),
i=i)
i += 1
enum_decl += mcgen('''
} %(name)s;
''',
name=name)
return lookup_decl + enum_decl
def generate_union(name, typeinfo):
ret = mcgen('''
struct %(name)s
{
%(name)sKind kind;
union {
void *data;
''',
name=name)
for key in typeinfo:
ret += mcgen('''
%(c_type)s %(c_name)s;
''',
c_type=c_type(typeinfo[key]),
c_name=c_fun(key))
ret += mcgen('''
};
};
''')
return ret
def generate_type_cleanup_decl(name):
ret = mcgen('''
void qapi_free_%(type)s(%(c_type)s obj);
''',
c_type=c_type(name),type=name)
return ret
def generate_type_cleanup(name):
ret = mcgen('''
void qapi_free_%(type)s(%(c_type)s obj)
{
QapiDeallocVisitor *md;
Visitor *v;
if (!obj) {
return;
}
md = qapi_dealloc_visitor_new();
v = qapi_dealloc_get_visitor(md);
visit_type_%(type)s(v, &obj, NULL, NULL);
qapi_dealloc_visitor_cleanup(md);
}
''',
c_type=c_type(name),type=name)
return ret
try:
opts, args = getopt.gnu_getopt(sys.argv[1:], "chbp:o:",
["source", "header", "builtins",
"prefix=", "output-dir="])
except getopt.GetoptError, err:
print str(err)
sys.exit(1)
output_dir = ""
prefix = ""
c_file = 'qapi-types.c'
h_file = 'qapi-types.h'
do_c = False
do_h = False
do_builtins = 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
elif o in ("-b", "--builtins"):
do_builtins = 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('''
/* AUTOMATICALLY GENERATED, DO NOT MODIFY */
/*
* deallocation functions for schema-defined QAPI types
*
* 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 LGPL, version 2.1 or later.
* See the COPYING.LIB file in the top-level directory.
*
*/
#include "qapi/dealloc-visitor.h"
#include "%(prefix)sqapi-types.h"
#include "%(prefix)sqapi-visit.h"
''', prefix=prefix))
fdecl.write(mcgen('''
/* AUTOMATICALLY GENERATED, DO NOT MODIFY */
/*
* schema-defined QAPI types
*
* 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 <stdbool.h>
#include <stdint.h>
''',
guard=guardname(h_file)))
exprs = parse_schema(sys.stdin)
exprs = filter(lambda expr: not expr.has_key('gen'), exprs)
fdecl.write(guardstart("QAPI_TYPES_BUILTIN_STRUCT_DECL"))
for typename in builtin_types:
fdecl.write(generate_fwd_struct(typename, None, builtin_type=True))
fdecl.write(guardend("QAPI_TYPES_BUILTIN_STRUCT_DECL"))
for expr in exprs:
ret = "\n"
if expr.has_key('type'):
ret += generate_fwd_struct(expr['type'], expr['data'])
elif expr.has_key('enum'):
ret += generate_enum(expr['enum'], expr['data']) + "\n"
ret += generate_fwd_enum_struct(expr['enum'], expr['data'])
fdef.write(generate_enum_lookup(expr['enum'], expr['data']))
elif expr.has_key('union'):
ret += generate_fwd_struct(expr['union'], expr['data']) + "\n"
ret += generate_enum('%sKind' % expr['union'], expr['data'].keys())
fdef.write(generate_enum_lookup('%sKind' % expr['union'], expr['data'].keys()))
else:
continue
fdecl.write(ret)
# to avoid header dependency hell, we always generate declarations
# for built-in types in our header files and simply guard them
fdecl.write(guardstart("QAPI_TYPES_BUILTIN_CLEANUP_DECL"))
for typename in builtin_types:
fdecl.write(generate_type_cleanup_decl(typename + "List"))
fdecl.write(guardend("QAPI_TYPES_BUILTIN_CLEANUP_DECL"))
# ...this doesn't work for cases where we link in multiple objects that
# have the functions defined, so we use -b option to provide control
# over these cases
if do_builtins:
fdef.write(guardstart("QAPI_TYPES_BUILTIN_CLEANUP_DEF"))
for typename in builtin_types:
fdef.write(generate_type_cleanup(typename + "List"))
fdef.write(guardend("QAPI_TYPES_BUILTIN_CLEANUP_DEF"))
for expr in exprs:
ret = "\n"
if expr.has_key('type'):
ret += generate_struct(expr['type'], "", expr['data']) + "\n"
ret += generate_type_cleanup_decl(expr['type'] + "List")
fdef.write(generate_type_cleanup(expr['type'] + "List") + "\n")
ret += generate_type_cleanup_decl(expr['type'])
fdef.write(generate_type_cleanup(expr['type']) + "\n")
elif expr.has_key('union'):
ret += generate_union(expr['union'], expr['data'])
ret += generate_type_cleanup_decl(expr['union'] + "List")
fdef.write(generate_type_cleanup(expr['union'] + "List") + "\n")
ret += generate_type_cleanup_decl(expr['union'])
fdef.write(generate_type_cleanup(expr['union']) + "\n")
elif expr.has_key('enum'):
ret += generate_type_cleanup_decl(expr['enum'] + "List")
fdef.write(generate_type_cleanup(expr['enum'] + "List") + "\n")
else:
continue
fdecl.write(ret)
fdecl.write('''
#endif
''')
fdecl.flush()
fdecl.close()
fdef.flush()
fdef.close()