scripts/qapi-commands.py

#
# QAPI command marshaller generator
#
# Copyright IBM, Corp. 2011
# Copyright (C) 2014-2015 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 ordereddict import OrderedDict
from qapi import *
import re

def generate_command_decl(name, args, ret_type):
    arglist=""
    for argname, argtype, optional in parse_args(args):
        argtype = c_type(argtype, is_param=True)
        if optional:
            arglist += "bool has_%s, " % c_name(argname)
        arglist += "%s %s, " % (argtype, c_name(argname))
    return mcgen('''
%(ret_type)s qmp_%(name)s(%(args)sError **errp);
''',
                 ret_type=c_type(ret_type), name=c_name(name),
                 args=arglist).strip()

def gen_err_check(errvar):
    if errvar:
        return mcgen('''
if (local_err) {
    goto out;
}
''')
    return ''

def gen_sync_call(name, args, ret_type, indent=0):
    ret = ""
    arglist=""
    retval=""
    if ret_type:
        retval = "retval = "
    for argname, argtype, optional in parse_args(args):
        if optional:
            arglist += "has_%s, " % c_name(argname)
        arglist += "%s, " % (c_name(argname))
    push_indent(indent)
    ret = mcgen('''
%(retval)sqmp_%(name)s(%(args)s&local_err);

''',
                name=c_name(name), args=arglist, retval=retval).rstrip()
    if ret_type:
        ret += "\n" + gen_err_check('local_err')
        ret += "\n" + mcgen('''
%(marshal_output_call)s
''',
                            marshal_output_call=gen_marshal_output_call(name, ret_type)).rstrip()
    pop_indent(indent)
    return ret.rstrip()


def gen_marshal_output_call(name, ret_type):
    if not ret_type:
        return ""
    return "qmp_marshal_output_%s(retval, ret, &local_err);" % c_name(name)

def gen_visitor_input_containers_decl(args, obj):
    ret = ""

    push_indent()
    if len(args) > 0:
        ret += mcgen('''
QmpInputVisitor *mi = qmp_input_visitor_new_strict(%(obj)s);
QapiDeallocVisitor *md;
Visitor *v;
''',
                     obj=obj)
    pop_indent()

    return ret.rstrip()

def gen_visitor_input_vars_decl(args):
    ret = ""
    push_indent()
    for argname, argtype, optional in parse_args(args):
        if optional:
            ret += mcgen('''
bool has_%(argname)s = false;
''',
                         argname=c_name(argname))
        if is_c_ptr(argtype):
            ret += mcgen('''
%(argtype)s %(argname)s = NULL;
''',
                         argname=c_name(argname), argtype=c_type(argtype))
        else:
            ret += mcgen('''
%(argtype)s %(argname)s = {0};
''',
                         argname=c_name(argname), argtype=c_type(argtype))

    pop_indent()
    return ret.rstrip()

def gen_visitor_input_block(args, dealloc=False):
    ret = ""
    errparg = '&local_err'
    errarg = 'local_err'

    if len(args) == 0:
        return ret

    push_indent()

    if dealloc:
        errparg = 'NULL'
        errarg = None;
        ret += mcgen('''
qmp_input_visitor_cleanup(mi);
md = qapi_dealloc_visitor_new();
v = qapi_dealloc_get_visitor(md);
''')
    else:
        ret += mcgen('''
v = qmp_input_get_visitor(mi);
''')

    for argname, argtype, optional in parse_args(args):
        if optional:
            ret += mcgen('''
visit_optional(v, &has_%(c_name)s, "%(name)s", %(errp)s);
''',
                         c_name=c_name(argname), name=argname, errp=errparg)
            ret += gen_err_check(errarg)
            ret += mcgen('''
if (has_%(c_name)s) {
''',
                         c_name=c_name(argname))
            push_indent()
        ret += mcgen('''
visit_type_%(visitor)s(v, &%(c_name)s, "%(name)s", %(errp)s);
''',
                     c_name=c_name(argname), name=argname, argtype=argtype,
                     visitor=type_name(argtype), errp=errparg)
        ret += gen_err_check(errarg)
        if optional:
            pop_indent()
            ret += mcgen('''
}
''')

    if dealloc:
        ret += mcgen('''
qapi_dealloc_visitor_cleanup(md);
''')
    pop_indent()
    return ret.rstrip()

def gen_marshal_output(name, args, ret_type, middle_mode):
    if not ret_type:
        return ""

    ret = mcgen('''
static void qmp_marshal_output_%(c_name)s(%(c_ret_type)s ret_in, QObject **ret_out, Error **errp)
{
    Error *local_err = NULL;
    QmpOutputVisitor *mo = qmp_output_visitor_new();
    QapiDeallocVisitor *md;
    Visitor *v;

    v = qmp_output_get_visitor(mo);
    visit_type_%(visitor)s(v, &ret_in, "unused", &local_err);
    if (local_err) {
        goto out;
    }
    *ret_out = qmp_output_get_qobject(mo);

out:
    error_propagate(errp, local_err);
    qmp_output_visitor_cleanup(mo);
    md = qapi_dealloc_visitor_new();
    v = qapi_dealloc_get_visitor(md);
    visit_type_%(visitor)s(v, &ret_in, "unused", NULL);
    qapi_dealloc_visitor_cleanup(md);
}
''',
                c_ret_type=c_type(ret_type), c_name=c_name(name),
                visitor=type_name(ret_type))

    return ret

def gen_marshal_input_decl(name, args, ret_type, middle_mode):
    ret = 'void qmp_marshal_input_%s(QDict *args, QObject **ret, Error **errp)' % c_name(name)
    if not middle_mode:
        ret = "static " + ret
    return ret

def gen_marshal_input(name, args, ret_type, middle_mode):
    hdr = gen_marshal_input_decl(name, args, ret_type, middle_mode)

    ret = mcgen('''
%(header)s
{
    Error *local_err = NULL;
''',
                header=hdr)

    if ret_type:
        if is_c_ptr(ret_type):
            retval = "    %s retval = NULL;" % c_type(ret_type)
        else:
            retval = "    %s retval;" % c_type(ret_type)
        ret += mcgen('''
%(retval)s
''',
                     retval=retval)

    if len(args) > 0:
        ret += mcgen('''
%(visitor_input_containers_decl)s
%(visitor_input_vars_decl)s

%(visitor_input_block)s

''',
                     visitor_input_containers_decl=gen_visitor_input_containers_decl(args, "QOBJECT(args)"),
                     visitor_input_vars_decl=gen_visitor_input_vars_decl(args),
                     visitor_input_block=gen_visitor_input_block(args))
    else:
        ret += mcgen('''

    (void)args;
''')

    ret += mcgen('''
%(sync_call)s
''',
                 sync_call=gen_sync_call(name, args, ret_type, indent=4))
    if re.search('^ *goto out\\;', ret, re.MULTILINE):
        ret += mcgen('''

out:
''')
    ret += mcgen('''
    error_propagate(errp, local_err);
%(visitor_input_block_cleanup)s
}
''',
                 visitor_input_block_cleanup=gen_visitor_input_block(args,
                                                                     dealloc=True))
    return ret

def gen_registry(commands):
    registry=""
    push_indent()
    for cmd in commands:
        options = 'QCO_NO_OPTIONS'
        if not cmd.get('success-response', True):
            options = 'QCO_NO_SUCCESS_RESP'

        registry += mcgen('''
qmp_register_command("%(name)s", qmp_marshal_input_%(c_name)s, %(opts)s);
''',
                     name=cmd['command'], c_name=c_name(cmd['command']),
                     opts=options)
    pop_indent()
    ret = mcgen('''
static void qmp_init_marshal(void)
{
%(registry)s
}

qapi_init(qmp_init_marshal);
''',
                registry=registry.rstrip())
    return ret

middle_mode = False

(input_file, output_dir, do_c, do_h, prefix, opts) = \
    parse_command_line("m", ["middle"])

for o, a in opts:
    if o in ("-m", "--middle"):
        middle_mode = True

exprs = parse_schema(input_file)
commands = filter(lambda expr: expr.has_key('command'), exprs)
commands = filter(lambda expr: not expr.has_key('gen'), commands)

c_comment = '''
/*
 * schema-defined QMP->QAPI command dispatch
 *
 * 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 function prototypes
 *
 * 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,
                            'qmp-marshal.c', 'qmp-commands.h',
                            c_comment, h_comment)

fdef.write(mcgen('''
#include "qemu-common.h"
#include "qemu/module.h"
#include "qapi/qmp/types.h"
#include "qapi/qmp/dispatch.h"
#include "qapi/visitor.h"
#include "qapi/qmp-output-visitor.h"
#include "qapi/qmp-input-visitor.h"
#include "qapi/dealloc-visitor.h"
#include "%(prefix)sqapi-types.h"
#include "%(prefix)sqapi-visit.h"
#include "%(prefix)sqmp-commands.h"

''',
                prefix=prefix))

fdecl.write(mcgen('''
#include "%(prefix)sqapi-types.h"
#include "qapi/qmp/qdict.h"
#include "qapi/error.h"

''',
                 prefix=prefix))

for cmd in commands:
    arglist = []
    ret_type = None
    if cmd.has_key('data'):
        arglist = cmd['data']
    if cmd.has_key('returns'):
        ret_type = cmd['returns']
    ret = generate_command_decl(cmd['command'], arglist, ret_type) + "\n"
    fdecl.write(ret)
    if ret_type:
        ret = gen_marshal_output(cmd['command'], arglist, ret_type, middle_mode) + "\n"
        fdef.write(ret)

    if middle_mode:
        fdecl.write('%s;\n' % gen_marshal_input_decl(cmd['command'], arglist, ret_type, middle_mode))

    ret = gen_marshal_input(cmd['command'], arglist, ret_type, middle_mode) + "\n"
    fdef.write(ret)

if not middle_mode:
    ret = gen_registry(commands)
    fdef.write(ret)

close_output(fdef, fdecl)