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 gen_event_send_proto(name, arg_type):
  18     return 'void qapi_event_send_%(c_name)s(%(param)s)' % {
  19         'c_name': c_name(name.lower()),
  20         'param': gen_params(arg_type, 'Error **errp')}
  21
  22
  23 def gen_event_send_decl(name, arg_type):
  24     return mcgen('''
  25
  26 %(proto)s;
  27 ''',
  28                  proto=gen_event_send_proto(name, arg_type))
  29
  30
  31 # Declare and initialize an object 'qapi' using parameters from gen_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 gen_params()
  46             ret += '(char *)'
  47         ret += c_name(memb.name)
  48     ret += mcgen('''
  49
  50     };
  51 ''')
  52     return ret
  53
  54
  55 def gen_event_send(name, arg_type):
  56     # FIXME: Our declaration of local variables (and of 'errp' in the
  57     # parameter list) can collide with exploded members of the event's
  58     # data type passed in as parameters.  If this collision ever hits in
  59     # practice, we can rename our local variables with a leading _ prefix,
  60     # or split the code into a wrapper function that creates a boxed
  61     # 'param' object then calls another to do the real work.
  62     ret = mcgen('''
  63
  64 %(proto)s
  65 {
  66     QDict *qmp;
  67     Error *err = NULL;
  68     QMPEventFuncEmit emit;
  69 ''',
  70                 proto=gen_event_send_proto(name, arg_type))
  71
  72     if arg_type and arg_type.members:
  73         ret += mcgen('''
  74     QmpOutputVisitor *qov;
  75     Visitor *v;
  76 ''')
  77         ret += gen_param_var(arg_type)
  78
  79     ret += mcgen('''
  80
  81     emit = qmp_event_get_func_emit();
  82     if (!emit) {
  83         return;
  84     }
  85
  86     qmp = qmp_event_build_dict("%(name)s");
  87
  88 ''',
  89                  name=name)
  90
  91     if arg_type and arg_type.members:
  92         ret += mcgen('''
  93     qov = qmp_output_visitor_new();
  94     v = qmp_output_get_visitor(qov);
  95
  96     visit_start_struct(v, "%(name)s", NULL, 0, &err);
  97     if (err) {
  98         goto out;
  99     }
 100     visit_type_%(c_name)s_members(v, &param, &err);
 101     if (!err) {
 102         visit_check_struct(v, &err);
 103     }
 104     visit_end_struct(v, NULL);
 105     if (err) {
 106         goto out;
 107     }
 108
 109     qdict_put_obj(qmp, "data", qmp_output_get_qobject(qov));
 110 ''',
 111                      name=name, c_name=arg_type.c_name())
 112
 113     ret += mcgen('''
 114     emit(%(c_enum)s, qmp, &err);
 115
 116 ''',
 117                  c_enum=c_enum_const(event_enum_name, name))
 118
 119     if arg_type and arg_type.members:
 120         ret += mcgen('''
 121 out:
 122     visit_free(v);
 123 ''')
 124     ret += mcgen('''
 125     error_propagate(errp, err);
 126     QDECREF(qmp);
 127 }
 128 ''')
 129     return ret
 130
 131
 132 class QAPISchemaGenEventVisitor(QAPISchemaVisitor):
 133     def __init__(self):
 134         self.decl = None
 135         self.defn = None
 136         self._event_names = None
 137
 138     def visit_begin(self, schema):
 139         self.decl = ''
 140         self.defn = ''
 141         self._event_names = []
 142
 143     def visit_end(self):
 144         self.decl += gen_enum(event_enum_name, self._event_names)
 145         self.defn += gen_enum_lookup(event_enum_name, self._event_names)
 146         self._event_names = None
 147
 148     def visit_event(self, name, info, arg_type):
 149         self.decl += gen_event_send_decl(name, arg_type)
 150         self.defn += gen_event_send(name, arg_type)
 151         self._event_names.append(name)
 152
 153
 154 (input_file, output_dir, do_c, do_h, prefix, dummy) = parse_command_line()
 155
 156 c_comment = '''
 157 /*
 158  * schema-defined QAPI event functions
 159  *
 160  * Copyright (c) 2014 Wenchao Xia
 161  *
 162  * Authors:
 163  *  Wenchao Xia   <wenchaoqemu@gmail.com>
 164  *
 165  * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
 166  * See the COPYING.LIB file in the top-level directory.
 167  *
 168  */
 169 '''
 170 h_comment = '''
 171 /*
 172  * schema-defined QAPI event functions
 173  *
 174  * Copyright (c) 2014 Wenchao Xia
 175  *
 176  * Authors:
 177  *  Wenchao Xia  <wenchaoqemu@gmail.com>
 178  *
 179  * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
 180  * See the COPYING.LIB file in the top-level directory.
 181  *
 182  */
 183 '''
 184
 185 (fdef, fdecl) = open_output(output_dir, do_c, do_h, prefix,
 186                             'qapi-event.c', 'qapi-event.h',
 187                             c_comment, h_comment)
 188
 189 fdef.write(mcgen('''
 190 #include "qemu/osdep.h"
 191 #include "qemu-common.h"
 192 #include "%(prefix)sqapi-event.h"
 193 #include "%(prefix)sqapi-visit.h"
 194 #include "qapi/qmp-output-visitor.h"
 195 #include "qapi/qmp-event.h"
 196
 197 ''',
 198                  prefix=prefix))
 199
 200 fdecl.write(mcgen('''
 201 #include "qapi/error.h"
 202 #include "qapi/qmp/qdict.h"
 203 #include "%(prefix)sqapi-types.h"
 204
 205 ''',
 206                   prefix=prefix))
 207
 208 event_enum_name = c_name(prefix + "QAPIEvent", protect=False)
 209
 210 schema = QAPISchema(input_file)
 211 gen = QAPISchemaGenEventVisitor()
 212 schema.visit(gen)
 213 fdef.write(gen.defn)
 214 fdecl.write(gen.decl)
 215
 216 close_output(fdef, fdecl)