dbus/helpers.c

   1 /* -*- Mode: C ; c-basic-offset: 2 -*- */
   2 /*
   3  * LADI Session Handler (ladish)
   4  *
   5  * Copyright (C) 2008, 2009 Nedko Arnaudov <nedko@arnaudov.name>
   6  * Copyright (C) 2008 Juuso Alasuutari <juuso.alasuutari@gmail.com>
   7  *
   8  **************************************************************************
   9  * This file contains code of the D-Bus helpers
  10  **************************************************************************
  11  *
  12  * LADI Session Handler is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU General Public License as published by
  14  * the Free Software Foundation; either version 2 of the License, or
  15  * (at your option) any later version.
  16  *
  17  * LADI Session Handler is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with LADI Session Handler. If not, see <http://www.gnu.org/licenses/>
  24  * or write to the Free Software Foundation, Inc.,
  25  * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  26  */
  27
  28 #include <stdbool.h>
  29 #include <dbus/dbus.h>
  30 #include <string.h>
  31 #include <assert.h>
  32
  33 #include "helpers.h"
  34 #include "method.h"
  35 #include "../common/debug.h"
  36
  37 DBusConnection * g_dbus_connection;
  38 DBusError g_dbus_error;
  39
  40 #define DBUS_CALL_DEFAULT_TIMEOUT 1000 // in milliseconds
  41
  42 bool dbus_maybe_add_dict_entry_string(DBusMessageIter *dict_iter_ptr, const char * key, const char * value)
  43 {
  44   DBusMessageIter dict_entry_iter;
  45
  46   if (value == NULL)
  47   {
  48     return true;
  49   }
  50
  51   if (!dbus_message_iter_open_container(dict_iter_ptr, DBUS_TYPE_DICT_ENTRY, NULL, &dict_entry_iter))
  52   {
  53     return false;
  54   }
  55
  56   if (!dbus_message_iter_append_basic(&dict_entry_iter, DBUS_TYPE_STRING, (const void *) &key))
  57   {
  58     dbus_message_iter_close_container(dict_iter_ptr, &dict_entry_iter);
  59     return false;
  60   }
  61
  62   method_iter_append_variant(&dict_entry_iter, DBUS_TYPE_STRING, &value);
  63
  64   if (!dbus_message_iter_close_container(dict_iter_ptr, &dict_entry_iter))
  65   {
  66     return false;
  67   }
  68
  69   return true;
  70 }
  71
  72 bool dbus_add_dict_entry_uint32(DBusMessageIter * dict_iter_ptr, const char * key, dbus_uint32_t value)
  73 {
  74   DBusMessageIter dict_entry_iter;
  75
  76   if (!dbus_message_iter_open_container(dict_iter_ptr, DBUS_TYPE_DICT_ENTRY, NULL, &dict_entry_iter))
  77   {
  78     return false;
  79   }
  80
  81   if (!dbus_message_iter_append_basic(&dict_entry_iter, DBUS_TYPE_STRING, (const void *) &key))
  82   {
  83     dbus_message_iter_close_container(dict_iter_ptr, &dict_entry_iter);
  84     return false;
  85   }
  86
  87   method_iter_append_variant(&dict_entry_iter, DBUS_TYPE_UINT32, &value);
  88
  89   if (!dbus_message_iter_close_container(dict_iter_ptr, &dict_entry_iter))
  90   {
  91     return false;
  92   }
  93
  94   return true;
  95 }
  96
  97 bool dbus_add_dict_entry_bool(DBusMessageIter * dict_iter_ptr, const char * key, dbus_bool_t value)
  98 {
  99   DBusMessageIter dict_entry_iter;
 100
 101   if (!dbus_message_iter_open_container(dict_iter_ptr, DBUS_TYPE_DICT_ENTRY, NULL, &dict_entry_iter))
 102   {
 103     return false;
 104   }
 105
 106   if (!dbus_message_iter_append_basic(&dict_entry_iter, DBUS_TYPE_STRING, (const void *) &key))
 107   {
 108     dbus_message_iter_close_container(dict_iter_ptr, &dict_entry_iter);
 109     return false;
 110   }
 111
 112   method_iter_append_variant(&dict_entry_iter, DBUS_TYPE_BOOLEAN, &value);
 113
 114   if (!dbus_message_iter_close_container(dict_iter_ptr, &dict_entry_iter))
 115   {
 116     return false;
 117   }
 118
 119   return true;
 120 }
 121
 122 bool
 123 dbus_call_simple(
 124   const char * service,
 125   const char * object,
 126   const char * iface,
 127   const char * method,
 128   char * input_signature,
 129   ...)
 130 {
 131   DBusMessageIter iter;
 132   DBusMessage * request_ptr;
 133   DBusMessage * reply_ptr;
 134   const char * output_signature;
 135   const char * reply_signature;
 136   va_list ap;
 137   bool ret;
 138   void * parameter_ptr;
 139   int type;
 140   DBusSignatureIter sig_iter;
 141
 142   lash_info("dbus_call_simple('%s', '%s', '%s', '%s')", service, object, iface, method);
 143
 144   ret = false;
 145   va_start(ap, input_signature);
 146
 147   if (!dbus_signature_validate(input_signature, NULL))
 148   {
 149     lash_error("input signature '%s' is invalid", input_signature);
 150     goto fail;
 151   }
 152
 153   dbus_signature_iter_init(&sig_iter, input_signature);
 154
 155   request_ptr = dbus_message_new_method_call(service, object, iface, method);
 156   if (request_ptr == NULL)
 157   {
 158     lash_error("dbus_message_new_method_call() failed.");
 159     goto fail;
 160   }
 161
 162   dbus_message_iter_init_append(request_ptr, &iter);
 163
 164   while (*input_signature != '\0')
 165   {
 166     type = dbus_signature_iter_get_current_type(&sig_iter);
 167     if (!dbus_type_is_basic(type))
 168     {
 169       lash_error("non-basic input parameter '%c' (%d)", *input_signature, type);
 170       goto fail;
 171     }
 172
 173     parameter_ptr = va_arg(ap, void *);
 174
 175     if (!dbus_message_iter_append_basic(&iter, type, parameter_ptr))
 176     {
 177       lash_error("dbus_message_iter_append_basic() failed.");
 178       goto fail;
 179     }
 180
 181     dbus_signature_iter_next(&sig_iter);
 182     input_signature++;
 183   }
 184
 185   output_signature = va_arg(ap, const char *);
 186
 187   reply_ptr = dbus_connection_send_with_reply_and_block(
 188     g_dbus_connection,
 189     request_ptr,
 190     DBUS_CALL_DEFAULT_TIMEOUT,
 191     &g_dbus_error);
 192
 193   dbus_message_unref(request_ptr);
 194
 195   if (reply_ptr == NULL)
 196   {
 197     lash_error("calling method '%s' failed, error is '%s'", method, g_dbus_error.message);
 198     dbus_error_free(&g_dbus_error);
 199     goto fail;
 200   }
 201
 202   reply_signature = dbus_message_get_signature(reply_ptr);
 203
 204   if (strcmp(reply_signature, output_signature) != 0)
 205   {
 206     lash_error("reply signature is '%s' but expected signature is '%s'", reply_signature, output_signature);
 207   }
 208
 209   dbus_message_iter_init(reply_ptr, &iter);
 210
 211   while (*output_signature++ != '\0')
 212   {
 213     assert(dbus_message_iter_get_arg_type(&iter) != DBUS_TYPE_INVALID); /* we've checked the signature, this should not happen */
 214     parameter_ptr = va_arg(ap, void *);
 215     dbus_message_iter_get_basic(&iter, parameter_ptr);
 216     dbus_message_iter_next(&iter);
 217   }
 218
 219   assert(dbus_message_iter_get_arg_type(&iter) == DBUS_TYPE_INVALID); /* we've checked the signature, this should not happen */
 220
 221   ret = true;
 222
 223 fail:
 224   va_end(ap);
 225   return ret;
 226 }
 227