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 from qapi.gen import QAPIGenCCode, QAPISchemaModularCVisitor, ifcontext
  18
  19
  20 def gen_command_decl(name, arg_type, boxed, ret_type):
  21     return mcgen('''
  22 %(c_type)s qmp_%(c_name)s(%(params)s);
  23 ''',
  24                  c_type=(ret_type and ret_type.c_type()) or 'void',
  25                  c_name=c_name(name),
  26                  params=build_params(arg_type, boxed, 'Error **errp'))
  27
  28
  29 def gen_call(name, arg_type, boxed, ret_type):
  30     ret = ''
  31
  32     argstr = ''
  33     if boxed:
  34         assert arg_type
  35         argstr = '&arg, '
  36     elif arg_type:
  37         assert not arg_type.variants
  38         for memb in arg_type.members:
  39             if memb.optional:
  40                 argstr += 'arg.has_%s, ' % c_name(memb.name)
  41             argstr += 'arg.%s, ' % c_name(memb.name)
  42
  43     lhs = ''
  44     if ret_type:
  45         lhs = 'retval = '
  46
  47     ret = mcgen('''
  48
  49     %(lhs)sqmp_%(c_name)s(%(args)s&err);
  50     error_propagate(errp, err);
  51 ''',
  52                 c_name=c_name(name), args=argstr, lhs=lhs)
  53     if ret_type:
  54         ret += mcgen('''
  55     if (err) {
  56         goto out;
  57     }
  58
  59     qmp_marshal_output_%(c_name)s(retval, ret, errp);
  60 ''',
  61                      c_name=ret_type.c_name())
  62     return ret
  63
  64
  65 def gen_marshal_output(ret_type):
  66     return mcgen('''
  67
  68 static void qmp_marshal_output_%(c_name)s(%(c_type)s ret_in, QObject **ret_out, Error **errp)
  69 {
  70     Visitor *v;
  71
  72     v = qobject_output_visitor_new(ret_out);
  73     if (visit_type_%(c_name)s(v, "unused", &ret_in, errp)) {
  74         visit_complete(v, ret_out);
  75     }
  76     visit_free(v);
  77     v = qapi_dealloc_visitor_new();
  78     visit_type_%(c_name)s(v, "unused", &ret_in, NULL);
  79     visit_free(v);
  80 }
  81 ''',
  82                  c_type=ret_type.c_type(), c_name=ret_type.c_name())
  83
  84
  85 def build_marshal_proto(name):
  86     return ('void qmp_marshal_%s(QDict *args, QObject **ret, Error **errp)'
  87             % c_name(name))
  88
  89
  90 def gen_marshal_decl(name):
  91     return mcgen('''
  92 %(proto)s;
  93 ''',
  94                  proto=build_marshal_proto(name))
  95
  96
  97 def gen_marshal(name, arg_type, boxed, ret_type):
  98     have_args = boxed or (arg_type and not arg_type.is_empty())
  99
 100     ret = mcgen('''
 101
 102 %(proto)s
 103 {
 104     Error *err = NULL;
 105     bool ok = false;
 106     Visitor *v;
 107 ''',
 108                 proto=build_marshal_proto(name))
 109
 110     if ret_type:
 111         ret += mcgen('''
 112     %(c_type)s retval;
 113 ''',
 114                      c_type=ret_type.c_type())
 115
 116     if have_args:
 117         ret += mcgen('''
 118     %(c_name)s arg = {0};
 119 ''',
 120                      c_name=arg_type.c_name())
 121
 122     ret += mcgen('''
 123
 124     v = qobject_input_visitor_new(QOBJECT(args));
 125     if (!visit_start_struct(v, NULL, NULL, 0, errp)) {
 126         goto out;
 127     }
 128 ''')
 129
 130     if have_args:
 131         ret += mcgen('''
 132     if (visit_type_%(c_arg_type)s_members(v, &arg, errp)) {
 133         ok = visit_check_struct(v, errp);
 134     }
 135 ''',
 136                      c_arg_type=arg_type.c_name())
 137     else:
 138         ret += mcgen('''
 139     ok = visit_check_struct(v, errp);
 140 ''')
 141
 142     ret += mcgen('''
 143     visit_end_struct(v, NULL);
 144     if (!ok) {
 145         goto out;
 146     }
 147 ''')
 148
 149     ret += gen_call(name, arg_type, boxed, ret_type)
 150
 151     ret += mcgen('''
 152
 153 out:
 154     visit_free(v);
 155 ''')
 156
 157     ret += mcgen('''
 158     v = qapi_dealloc_visitor_new();
 159     visit_start_struct(v, NULL, NULL, 0, NULL);
 160 ''')
 161
 162     if have_args:
 163         ret += mcgen('''
 164     visit_type_%(c_arg_type)s_members(v, &arg, NULL);
 165 ''',
 166                      c_arg_type=arg_type.c_name())
 167
 168     ret += mcgen('''
 169     visit_end_struct(v, NULL);
 170     visit_free(v);
 171 ''')
 172
 173     ret += mcgen('''
 174 }
 175 ''')
 176     return ret
 177
 178
 179 def gen_register_command(name, success_response, allow_oob, allow_preconfig):
 180     options = []
 181
 182     if not success_response:
 183         options += ['QCO_NO_SUCCESS_RESP']
 184     if allow_oob:
 185         options += ['QCO_ALLOW_OOB']
 186     if allow_preconfig:
 187         options += ['QCO_ALLOW_PRECONFIG']
 188
 189     if not options:
 190         options = ['QCO_NO_OPTIONS']
 191
 192     options = " | ".join(options)
 193
 194     ret = mcgen('''
 195     qmp_register_command(cmds, "%(name)s",
 196                          qmp_marshal_%(c_name)s, %(opts)s);
 197 ''',
 198                 name=name, c_name=c_name(name),
 199                 opts=options)
 200     return ret
 201
 202
 203 def gen_registry(registry, prefix):
 204     ret = mcgen('''
 205
 206 void %(c_prefix)sqmp_init_marshal(QmpCommandList *cmds)
 207 {
 208     QTAILQ_INIT(cmds);
 209
 210 ''',
 211                 c_prefix=c_name(prefix, protect=False))
 212     ret += registry
 213     ret += mcgen('''
 214 }
 215 ''')
 216     return ret
 217
 218
 219 class QAPISchemaGenCommandVisitor(QAPISchemaModularCVisitor):
 220
 221     def __init__(self, prefix):
 222         super().__init__(
 223             prefix, 'qapi-commands',
 224             ' * Schema-defined QAPI/QMP commands', None, __doc__)
 225         self._regy = QAPIGenCCode(None)
 226         self._visited_ret_types = {}
 227
 228     def _begin_user_module(self, name):
 229         self._visited_ret_types[self._genc] = set()
 230         commands = self._module_basename('qapi-commands', name)
 231         types = self._module_basename('qapi-types', name)
 232         visit = self._module_basename('qapi-visit', name)
 233         self._genc.add(mcgen('''
 234 #include "qemu/osdep.h"
 235 #include "qapi/visitor.h"
 236 #include "qapi/qmp/qdict.h"
 237 #include "qapi/qobject-output-visitor.h"
 238 #include "qapi/qobject-input-visitor.h"
 239 #include "qapi/dealloc-visitor.h"
 240 #include "qapi/error.h"
 241 #include "%(visit)s.h"
 242 #include "%(commands)s.h"
 243
 244 ''',
 245                              commands=commands, visit=visit))
 246         self._genh.add(mcgen('''
 247 #include "%(types)s.h"
 248
 249 ''',
 250                              types=types))
 251
 252     def visit_end(self):
 253         self._add_system_module('init', ' * QAPI Commands initialization')
 254         self._genh.add(mcgen('''
 255 #include "qapi/qmp/dispatch.h"
 256
 257 void %(c_prefix)sqmp_init_marshal(QmpCommandList *cmds);
 258 ''',
 259                              c_prefix=c_name(self._prefix, protect=False)))
 260         self._genc.preamble_add(mcgen('''
 261 #include "qemu/osdep.h"
 262 #include "%(prefix)sqapi-commands.h"
 263 #include "%(prefix)sqapi-init-commands.h"
 264 ''',
 265                                       prefix=self._prefix))
 266         self._genc.add(gen_registry(self._regy.get_content(), self._prefix))
 267
 268     def visit_command(self, name, info, ifcond, features,
 269                       arg_type, ret_type, gen, success_response, boxed,
 270                       allow_oob, allow_preconfig):
 271         if not gen:
 272             return
 273         # FIXME: If T is a user-defined type, the user is responsible
 274         # for making this work, i.e. to make T's condition the
 275         # conjunction of the T-returning commands' conditions.  If T
 276         # is a built-in type, this isn't possible: the
 277         # qmp_marshal_output_T() will be generated unconditionally.
 278         if ret_type and ret_type not in self._visited_ret_types[self._genc]:
 279             self._visited_ret_types[self._genc].add(ret_type)
 280             with ifcontext(ret_type.ifcond,
 281                            self._genh, self._genc, self._regy):
 282                 self._genc.add(gen_marshal_output(ret_type))
 283         with ifcontext(ifcond, self._genh, self._genc, self._regy):
 284             self._genh.add(gen_command_decl(name, arg_type, boxed, ret_type))
 285             self._genh.add(gen_marshal_decl(name))
 286             self._genc.add(gen_marshal(name, arg_type, boxed, ret_type))
 287             self._regy.add(gen_register_command(name, success_response,
 288                                                 allow_oob, allow_preconfig))
 289
 290
 291 def gen_commands(schema, output_dir, prefix):
 292     vis = QAPISchemaGenCommandVisitor(prefix)
 293     schema.visit(vis)
 294     vis.write(output_dir)