scripts/qapi/commands.py

   1 """
   2 QAPI command marshaller generator
   3
   4 Copyright IBM, Corp. 2011
   5 Copyright (C) 2014-2018 Red Hat, Inc.
   6
   7 Authors:
   8  Anthony Liguori <aliguori@us.ibm.com>
   9  Michael Roth <mdroth@linux.vnet.ibm.com>
  10  Markus Armbruster <armbru@redhat.com>
  11
  12 This work is licensed under the terms of the GNU GPL, version 2.
  13 See the COPYING file in the top-level directory.
  14 """
  15
  16 from qapi.common import *
  17
  18
  19 def gen_command_decl(name, arg_type, boxed, ret_type):
  20     return mcgen('''
  21 %(c_type)s qmp_%(c_name)s(%(params)s);
  22 ''',
  23                  c_type=(ret_type and ret_type.c_type()) or 'void',
  24                  c_name=c_name(name),
  25                  params=build_params(arg_type, boxed, 'Error **errp'))
  26
  27
  28 def gen_call(name, arg_type, boxed, ret_type):
  29     ret = ''
  30
  31     argstr = ''
  32     if boxed:
  33         assert arg_type and not arg_type.is_empty()
  34         argstr = '&arg, '
  35     elif arg_type:
  36         assert not arg_type.variants
  37         for memb in arg_type.members:
  38             if memb.optional:
  39                 argstr += 'arg.has_%s, ' % c_name(memb.name)
  40             argstr += 'arg.%s, ' % c_name(memb.name)
  41
  42     lhs = ''
  43     if ret_type:
  44         lhs = 'retval = '
  45
  46     ret = mcgen('''
  47
  48     %(lhs)sqmp_%(c_name)s(%(args)s&err);
  49 ''',
  50                 c_name=c_name(name), args=argstr, lhs=lhs)
  51     if ret_type:
  52         ret += mcgen('''
  53     if (err) {
  54         goto out;
  55     }
  56
  57     qmp_marshal_output_%(c_name)s(retval, ret, &err);
  58 ''',
  59                      c_name=ret_type.c_name())
  60     return ret
  61
  62
  63 def gen_marshal_output(ret_type):
  64     return mcgen('''
  65
  66 static void qmp_marshal_output_%(c_name)s(%(c_type)s ret_in, QObject **ret_out, Error **errp)
  67 {
  68     Error *err = NULL;
  69     Visitor *v;
  70
  71     v = qobject_output_visitor_new(ret_out);
  72     visit_type_%(c_name)s(v, "unused", &ret_in, &err);
  73     if (!err) {
  74         visit_complete(v, ret_out);
  75     }
  76     error_propagate(errp, err);
  77     visit_free(v);
  78     v = qapi_dealloc_visitor_new();
  79     visit_type_%(c_name)s(v, "unused", &ret_in, NULL);
  80     visit_free(v);
  81 }
  82 ''',
  83                  c_type=ret_type.c_type(), c_name=ret_type.c_name())
  84
  85
  86 def build_marshal_proto(name):
  87     return ('void qmp_marshal_%s(QDict *args, QObject **ret, Error **errp)'
  88             % c_name(name))
  89
  90
  91 def gen_marshal_decl(name):
  92     return mcgen('''
  93 %(proto)s;
  94 ''',
  95                  proto=build_marshal_proto(name))
  96
  97
  98 def gen_marshal(name, arg_type, boxed, ret_type):
  99     have_args = arg_type and not arg_type.is_empty()
 100
 101     ret = mcgen('''
 102
 103 %(proto)s
 104 {
 105     Error *err = NULL;
 106 ''',
 107                 proto=build_marshal_proto(name))
 108
 109     if ret_type:
 110         ret += mcgen('''
 111     %(c_type)s retval;
 112 ''',
 113                      c_type=ret_type.c_type())
 114
 115     if have_args:
 116         visit_members = ('visit_type_%s_members(v, &arg, &err);'
 117                          % arg_type.c_name())
 118         ret += mcgen('''
 119     Visitor *v;
 120     %(c_name)s arg = {0};
 121
 122 ''',
 123                      c_name=arg_type.c_name())
 124     else:
 125         visit_members = ''
 126         ret += mcgen('''
 127     Visitor *v = NULL;
 128
 129     if (args) {
 130 ''')
 131         push_indent()
 132
 133     ret += mcgen('''
 134     v = qobject_input_visitor_new(QOBJECT(args));
 135     visit_start_struct(v, NULL, NULL, 0, &err);
 136     if (err) {
 137         goto out;
 138     }
 139     %(visit_members)s
 140     if (!err) {
 141         visit_check_struct(v, &err);
 142     }
 143     visit_end_struct(v, NULL);
 144     if (err) {
 145         goto out;
 146     }
 147 ''',
 148                  visit_members=visit_members)
 149
 150     if not have_args:
 151         pop_indent()
 152         ret += mcgen('''
 153     }
 154 ''')
 155
 156     ret += gen_call(name, arg_type, boxed, ret_type)
 157
 158     ret += mcgen('''
 159
 160 out:
 161     error_propagate(errp, err);
 162     visit_free(v);
 163 ''')
 164
 165     if have_args:
 166         visit_members = ('visit_type_%s_members(v, &arg, NULL);'
 167                          % arg_type.c_name())
 168     else:
 169         visit_members = ''
 170         ret += mcgen('''
 171     if (args) {
 172 ''')
 173         push_indent()
 174
 175     ret += mcgen('''
 176     v = qapi_dealloc_visitor_new();
 177     visit_start_struct(v, NULL, NULL, 0, NULL);
 178     %(visit_members)s
 179     visit_end_struct(v, NULL);
 180     visit_free(v);
 181 ''',
 182                  visit_members=visit_members)
 183
 184     if not have_args:
 185         pop_indent()
 186         ret += mcgen('''
 187     }
 188 ''')
 189
 190     ret += mcgen('''
 191 }
 192 ''')
 193     return ret
 194
 195
 196 def gen_register_command(name, success_response, allow_oob, allow_preconfig):
 197     options = []
 198
 199     if not success_response:
 200         options += ['QCO_NO_SUCCESS_RESP']
 201     if allow_oob:
 202         options += ['QCO_ALLOW_OOB']
 203     if allow_preconfig:
 204         options += ['QCO_ALLOW_PRECONFIG']
 205
 206     if not options:
 207         options = ['QCO_NO_OPTIONS']
 208
 209     options = " | ".join(options)
 210
 211     ret = mcgen('''
 212     qmp_register_command(cmds, "%(name)s",
 213                          qmp_marshal_%(c_name)s, %(opts)s);
 214 ''',
 215                 name=name, c_name=c_name(name),
 216                 opts=options)
 217     return ret
 218
 219
 220 def gen_registry(registry, prefix):
 221     ret = mcgen('''
 222
 223 void %(c_prefix)sqmp_init_marshal(QmpCommandList *cmds)
 224 {
 225     QTAILQ_INIT(cmds);
 226
 227 ''',
 228                 c_prefix=c_name(prefix, protect=False))
 229     ret += registry
 230     ret += mcgen('''
 231 }
 232 ''')
 233     return ret
 234
 235
 236 class QAPISchemaGenCommandVisitor(QAPISchemaModularCVisitor):
 237
 238     def __init__(self, prefix):
 239         QAPISchemaModularCVisitor.__init__(
 240             self, prefix, 'qapi-commands',
 241             ' * Schema-defined QAPI/QMP commands', __doc__)
 242         self._regy = QAPIGenCCode()
 243         self._visited_ret_types = {}
 244
 245     def _begin_module(self, name):
 246         self._visited_ret_types[self._genc] = set()
 247         commands = self._module_basename('qapi-commands', name)
 248         types = self._module_basename('qapi-types', name)
 249         visit = self._module_basename('qapi-visit', name)
 250         self._genc.add(mcgen('''
 251 #include "qemu/osdep.h"
 252 #include "qemu-common.h"
 253 #include "qemu/module.h"
 254 #include "qapi/visitor.h"
 255 #include "qapi/qmp/qdict.h"
 256 #include "qapi/qobject-output-visitor.h"
 257 #include "qapi/qobject-input-visitor.h"
 258 #include "qapi/dealloc-visitor.h"
 259 #include "qapi/error.h"
 260 #include "%(visit)s.h"
 261 #include "%(commands)s.h"
 262
 263 ''',
 264                              commands=commands, visit=visit))
 265         self._genh.add(mcgen('''
 266 #include "%(types)s.h"
 267 #include "qapi/qmp/dispatch.h"
 268
 269 ''',
 270                              types=types))
 271
 272     def visit_end(self):
 273         (genc, genh) = self._module[self._main_module]
 274         genh.add(mcgen('''
 275 void %(c_prefix)sqmp_init_marshal(QmpCommandList *cmds);
 276 ''',
 277                        c_prefix=c_name(self._prefix, protect=False)))
 278         genc.add(gen_registry(self._regy.get_content(), self._prefix))
 279
 280     def visit_command(self, name, info, ifcond, arg_type, ret_type, gen,
 281                       success_response, boxed, allow_oob, allow_preconfig):
 282         if not gen:
 283             return
 284         # FIXME: If T is a user-defined type, the user is responsible
 285         # for making this work, i.e. to make T's condition the
 286         # conjunction of the T-returning commands' conditions.  If T
 287         # is a built-in type, this isn't possible: the
 288         # qmp_marshal_output_T() will be generated unconditionally.
 289         if ret_type and ret_type not in self._visited_ret_types[self._genc]:
 290             self._visited_ret_types[self._genc].add(ret_type)
 291             with ifcontext(ret_type.ifcond,
 292                            self._genh, self._genc, self._regy):
 293                 self._genc.add(gen_marshal_output(ret_type))
 294         with ifcontext(ifcond, self._genh, self._genc, self._regy):
 295             self._genh.add(gen_command_decl(name, arg_type, boxed, ret_type))
 296             self._genh.add(gen_marshal_decl(name))
 297             self._genc.add(gen_marshal(name, arg_type, boxed, ret_type))
 298             self._regy.add(gen_register_command(name, success_response,
 299                                                 allow_oob, allow_preconfig))
 300
 301
 302 def gen_commands(schema, output_dir, prefix):
 303     vis = QAPISchemaGenCommandVisitor(prefix)
 304     schema.visit(vis)
 305     vis.write(output_dir)