scripts/qapi-event.py

   1 #
   2 # QAPI event generator
   3 #
   4 # Copyright (c) 2014 Wenchao Xia
   5 # Copyright (c) 2015-2016 Red Hat Inc.
   6 #
   7 # Authors:
   8 #  Wenchao Xia <wenchaoqemu@gmail.com>
   9 #  Markus Armbruster <armbru@redhat.com>
  10 #
  11 # This work is licensed under the terms of the GNU GPL, version 2.
  12 # See the COPYING file in the top-level directory.
  13
  14 from qapi import *
  15
  16
  17 def build_event_send_proto(name, arg_type, boxed):
  18     return 'void qapi_event_send_%(c_name)s(%(param)s)' % {
  19         'c_name': c_name(name.lower()),
  20         'param': build_params(arg_type, boxed, 'Error **errp')}
  21
  22
  23 def gen_event_send_decl(name, arg_type, boxed):
  24     return mcgen('''
  25
  26 %(proto)s;
  27 ''',
  28                  proto=build_event_send_proto(name, arg_type, boxed))
  29
  30
  31 # Declare and initialize an object 'qapi' using parameters from build_params()
  32 def gen_param_var(typ):
  33     assert not typ.variants
  34     ret = mcgen('''
  35     %(c_name)s param = {
  36 ''',
  37                 c_name=typ.c_name())
  38     sep = '        '
  39     for memb in typ.members:
  40         ret += sep
  41         sep = ', '
  42         if memb.optional:
  43             ret += 'has_' + c_name(memb.name) + sep
  44         if memb.type.name == 'str':
  45             # Cast away const added in build_params()
  46             ret += '(char *)'
  47         ret += c_name(memb.name)
  48     ret += mcgen('''
  49
  50     };
  51 ''')
  52     if not typ.is_implicit():
  53         ret += mcgen('''
  54     %(c_name)s *arg = &param;
  55 ''',
  56                      c_name=typ.c_name())
  57     return ret
  58
  59
  60 def gen_event_send(name, arg_type, boxed):
  61     # FIXME: Our declaration of local variables (and of 'errp' in the
  62     # parameter list) can collide with exploded members of the event's
  63     # data type passed in as parameters.  If this collision ever hits in
  64     # practice, we can rename our local variables with a leading _ prefix,
  65     # or split the code into a wrapper function that creates a boxed
  66     # 'param' object then calls another to do the real work.
  67     ret = mcgen('''
  68
  69 %(proto)s
  70 {
  71     QDict *qmp;
  72     Error *err = NULL;
  73     QMPEventFuncEmit emit;
  74 ''',
  75                 proto=build_event_send_proto(name, arg_type, boxed))
  76
  77     if arg_type and not arg_type.is_empty():
  78         ret += mcgen('''
  79     QObject *obj;
  80     Visitor *v;
  81 ''')
  82         if not boxed:
  83             ret += gen_param_var(arg_type)
  84     else:
  85         assert not boxed
  86
  87     ret += mcgen('''
  88
  89     emit = qmp_event_get_func_emit();
  90     if (!emit) {
  91         return;
  92     }
  93
  94     qmp = qmp_event_build_dict("%(name)s");
  95
  96 ''',
  97                  name=name)
  98
  99     if arg_type and not arg_type.is_empty():
 100         ret += mcgen('''
 101     v = qobject_output_visitor_new(&obj);
 102 ''')
 103         if not arg_type.is_implicit():
 104             ret += mcgen('''
 105     visit_type_%(c_name)s(v, "%(name)s", &arg, &err);
 106 ''',
 107                          name=name, c_name=arg_type.c_name())
 108         else:
 109             ret += mcgen('''
 110
 111     visit_start_struct(v, "%(name)s", NULL, 0, &err);
 112     if (err) {
 113         goto out;
 114     }
 115     visit_type_%(c_name)s_members(v, &param, &err);
 116     if (!err) {
 117         visit_check_struct(v, &err);
 118     }
 119     visit_end_struct(v, NULL);
 120 ''',
 121                          name=name, c_name=arg_type.c_name())
 122         ret += mcgen('''
 123     if (err) {
 124         goto out;
 125     }
 126
 127     visit_complete(v, &obj);
 128     qdict_put_obj(qmp, "data", obj);
 129 ''')
 130
 131     ret += mcgen('''
 132     emit(%(c_enum)s, qmp, &err);
 133
 134 ''',
 135                  c_enum=c_enum_const(event_enum_name, name))
 136
 137     if arg_type and not arg_type.is_empty():
 138         ret += mcgen('''
 139 out:
 140     visit_free(v);
 141 ''')
 142     ret += mcgen('''
 143     error_propagate(errp, err);
 144     QDECREF(qmp);
 145 }
 146 ''')
 147     return ret
 148
 149
 150 class QAPISchemaGenEventVisitor(QAPISchemaVisitor):
 151     def __init__(self):
 152         self.decl = None
 153         self.defn = None
 154         self._event_names = None
 155
 156     def visit_begin(self, schema):
 157         self.decl = ''
 158         self.defn = ''
 159         self._event_names = []
 160
 161     def visit_end(self):
 162         self.decl += gen_enum(event_enum_name, self._event_names)
 163         self.defn += gen_enum_lookup(event_enum_name, self._event_names)
 164         self._event_names = None
 165
 166     def visit_event(self, name, info, arg_type, boxed):
 167         self.decl += gen_event_send_decl(name, arg_type, boxed)
 168         self.defn += gen_event_send(name, arg_type, boxed)
 169         self._event_names.append(name)
 170
 171
 172 (input_file, output_dir, do_c, do_h, prefix, dummy) = parse_command_line()
 173
 174 c_comment = '''
 175 /*
 176  * schema-defined QAPI event functions
 177  *
 178  * Copyright (c) 2014 Wenchao Xia
 179  *
 180  * Authors:
 181  *  Wenchao Xia   <wenchaoqemu@gmail.com>
 182  *
 183  * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
 184  * See the COPYING.LIB file in the top-level directory.
 185  *
 186  */
 187 '''
 188 h_comment = '''
 189 /*
 190  * schema-defined QAPI event functions
 191  *
 192  * Copyright (c) 2014 Wenchao Xia
 193  *
 194  * Authors:
 195  *  Wenchao Xia  <wenchaoqemu@gmail.com>
 196  *
 197  * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
 198  * See the COPYING.LIB file in the top-level directory.
 199  *
 200  */
 201 '''
 202
 203 (fdef, fdecl) = open_output(output_dir, do_c, do_h, prefix,
 204                             'qapi-event.c', 'qapi-event.h',
 205                             c_comment, h_comment)
 206
 207 fdef.write(mcgen('''
 208 #include "qemu/osdep.h"
 209 #include "qemu-common.h"
 210 #include "%(prefix)sqapi-event.h"
 211 #include "%(prefix)sqapi-visit.h"
 212 #include "qapi/qobject-output-visitor.h"
 213 #include "qapi/qmp-event.h"
 214
 215 ''',
 216                  prefix=prefix))
 217
 218 fdecl.write(mcgen('''
 219 #include "qapi/error.h"
 220 #include "qapi/util.h"
 221 #include "qapi/qmp/qdict.h"
 222 #include "%(prefix)sqapi-types.h"
 223
 224 ''',
 225                   prefix=prefix))
 226
 227 event_enum_name = c_name(prefix + 'QAPIEvent', protect=False)
 228
 229 schema = QAPISchema(input_file)
 230 gen = QAPISchemaGenEventVisitor()
 231 schema.visit(gen)
 232 fdef.write(gen.defn)
 233 fdecl.write(gen.decl)
 234
 235 close_output(fdef, fdecl)