git.maemo.org Git - connman/blob - gdbus/watch.c

   1 /*
   2  *
   3  *  D-Bus helper library
   4  *
   5  *  Copyright (C) 2004-2009  Marcel Holtmann <marcel@holtmann.org>
   6  *
   7  *
   8  *  This program is free software; you can redistribute it and/or modify
   9  *  it under the terms of the GNU General Public License as published by
  10  *  the Free Software Foundation; either version 2 of the License, or
  11  *  (at your option) any later version.
  12  *
  13  *  This program is distributed in the hope that it will be useful,
  14  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  *  GNU General Public License for more details.
  17  *
  18  *  You should have received a copy of the GNU General Public License
  19  *  along with this program; if not, write to the Free Software
  20  *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  21  *
  22  */
  23
  24 #ifdef HAVE_CONFIG_H
  25 #include <config.h>
  26 #endif
  27
  28 #include <stdio.h>
  29 #include <string.h>
  30
  31 #include <glib.h>
  32 #include <dbus/dbus.h>
  33
  34 #include "gdbus.h"
  35
  36 #define info(fmt...)
  37 #define error(fmt...)
  38 #define debug(fmt...)
  39
  40 static guint listener_id = 0;
  41 static GSList *name_listeners = NULL;
  42
  43 struct name_callback {
  44         GDBusWatchFunction conn_func;
  45         GDBusWatchFunction disc_func;
  46         void *user_data;
  47         guint id;
  48 };
  49
  50 struct name_data {
  51         DBusConnection *connection;
  52         char *name;
  53         GSList *callbacks;
  54 };
  55
  56 static struct name_data *name_data_find(DBusConnection *connection,
  57                                                         const char *name)
  58 {
  59         GSList *current;
  60
  61         for (current = name_listeners;
  62                         current != NULL; current = current->next) {
  63                 struct name_data *data = current->data;
  64
  65                 if (name == NULL && data->name == NULL) {
  66                         if (connection == data->connection)
  67                                 return data;
  68                 } else {
  69                         if (strcmp(name, data->name) == 0)
  70                                 return data;
  71                 }
  72         }
  73
  74         return NULL;
  75 }
  76
  77 static struct name_callback *name_callback_find(GSList *callbacks, guint id)
  78 {
  79         GSList *current;
  80
  81         for (current = callbacks; current != NULL; current = current->next) {
  82                 struct name_callback *cb = current->data;
  83                 if (cb->id == id)
  84                         return cb;
  85         }
  86
  87         return NULL;
  88 }
  89
  90 static void name_data_call_and_free(struct name_data *data)
  91 {
  92         GSList *l;
  93
  94         for (l = data->callbacks; l != NULL; l = l->next) {
  95                 struct name_callback *cb = l->data;
  96                 if (cb->disc_func)
  97                         cb->disc_func(data->connection, cb->user_data);
  98                 g_free(cb);
  99         }
 100
 101         g_slist_free(data->callbacks);
 102         g_free(data->name);
 103         g_free(data);
 104 }
 105
 106 static void name_data_free(struct name_data *data)
 107 {
 108         GSList *l;
 109
 110         for (l = data->callbacks; l != NULL; l = l->next)
 111                 g_free(l->data);
 112
 113         g_slist_free(data->callbacks);
 114         g_free(data->name);
 115         g_free(data);
 116 }
 117
 118 static int name_data_add(DBusConnection *connection, const char *name,
 119                                                 GDBusWatchFunction connect,
 120                                                 GDBusWatchFunction disconnect,
 121                                                 void *user_data, guint id)
 122 {
 123         int first = 1;
 124         struct name_data *data = NULL;
 125         struct name_callback *cb = NULL;
 126
 127         cb = g_new(struct name_callback, 1);
 128
 129         cb->conn_func = connect;
 130         cb->disc_func = disconnect;
 131         cb->user_data = user_data;
 132         cb->id = id;
 133
 134         data = name_data_find(connection, name);
 135         if (data) {
 136                 first = 0;
 137                 goto done;
 138         }
 139
 140         data = g_new0(struct name_data, 1);
 141
 142         data->connection = connection;
 143         data->name = g_strdup(name);
 144
 145         name_listeners = g_slist_append(name_listeners, data);
 146
 147 done:
 148         data->callbacks = g_slist_append(data->callbacks, cb);
 149         return first;
 150 }
 151
 152 static void name_data_remove(DBusConnection *connection,
 153                                         const char *name, guint id)
 154 {
 155         struct name_data *data;
 156         struct name_callback *cb = NULL;
 157
 158         data = name_data_find(connection, name);
 159         if (!data)
 160                 return;
 161
 162         cb = name_callback_find(data->callbacks, id);
 163         if (cb) {
 164                 data->callbacks = g_slist_remove(data->callbacks, cb);
 165                 g_free(cb);
 166         }
 167
 168         if (!data->callbacks) {
 169                 name_listeners = g_slist_remove(name_listeners, data);
 170                 name_data_free(data);
 171         }
 172 }
 173
 174 static gboolean add_match(DBusConnection *connection, const char *name)
 175 {
 176         DBusError err;
 177         char match_string[128];
 178
 179         snprintf(match_string, sizeof(match_string),
 180                         "interface=%s,member=NameOwnerChanged,arg0=%s",
 181                         DBUS_INTERFACE_DBUS, name);
 182
 183         dbus_error_init(&err);
 184
 185         dbus_bus_add_match(connection, match_string, &err);
 186
 187         if (dbus_error_is_set(&err)) {
 188                 error("Adding match rule \"%s\" failed: %s", match_string,
 189                                 err.message);
 190                 dbus_error_free(&err);
 191                 return FALSE;
 192         }
 193
 194         return TRUE;
 195 }
 196
 197 static gboolean remove_match(DBusConnection *connection, const char *name)
 198 {
 199         DBusError err;
 200         char match_string[128];
 201
 202         snprintf(match_string, sizeof(match_string),
 203                         "interface=%s,member=NameOwnerChanged,arg0=%s",
 204                         DBUS_INTERFACE_DBUS, name);
 205
 206         dbus_error_init(&err);
 207
 208         dbus_bus_remove_match(connection, match_string, &err);
 209
 210         if (dbus_error_is_set(&err)) {
 211                 error("Removing owner match rule for %s failed: %s",
 212                                 name, err.message);
 213                 dbus_error_free(&err);
 214                 return FALSE;
 215         }
 216
 217         return TRUE;
 218 }
 219
 220 static DBusHandlerResult name_exit_filter(DBusConnection *connection,
 221                                         DBusMessage *message, void *user_data)
 222 {
 223         GSList *l;
 224         struct name_data *data;
 225         char *name, *old, *new;
 226         int keep = 0;
 227
 228         if (!dbus_message_is_signal(message, DBUS_INTERFACE_DBUS,
 229                                                         "NameOwnerChanged"))
 230                 return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 231
 232         if (!dbus_message_get_args(message, NULL,
 233                                 DBUS_TYPE_STRING, &name,
 234                                 DBUS_TYPE_STRING, &old,
 235                                 DBUS_TYPE_STRING, &new,
 236                                 DBUS_TYPE_INVALID)) {
 237                 error("Invalid arguments for NameOwnerChanged signal");
 238                 return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 239         }
 240
 241         data = name_data_find(connection, name);
 242         if (!data) {
 243                 error("Got NameOwnerChanged signal for %s which has no listeners", name);
 244                 return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 245         }
 246
 247         for (l = data->callbacks; l != NULL; l = l->next) {
 248                 struct name_callback *cb = l->data;
 249                 if (*new == '\0') {
 250                         if (cb->disc_func)
 251                                 cb->disc_func(connection, cb->user_data);
 252                 } else {
 253                         if (cb->conn_func)
 254                                 cb->conn_func(connection, cb->user_data);
 255                 }
 256                 if (cb->conn_func && cb->disc_func)
 257                         keep = 1;
 258         }
 259
 260         if (keep)
 261                 return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 262
 263         name_listeners = g_slist_remove(name_listeners, data);
 264         name_data_free(data);
 265
 266         remove_match(connection, name);
 267
 268         return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 269 }
 270
 271 guint g_dbus_add_service_watch(DBusConnection *connection, const char *name,
 272                                 GDBusWatchFunction connect,
 273                                 GDBusWatchFunction disconnect,
 274                                 void *user_data, GDBusDestroyFunction destroy)
 275 {
 276         int first;
 277
 278         if (!listener_id) {
 279                 if (!dbus_connection_add_filter(connection,
 280                                         name_exit_filter, NULL, NULL)) {
 281                         error("dbus_connection_add_filter() failed");
 282                         return 0;
 283                 }
 284         }
 285
 286         listener_id++;
 287         first = name_data_add(connection, name, connect, disconnect,
 288                                                 user_data, listener_id);
 289         /* The filter is already added if this is not the first callback
 290          * registration for the name */
 291         if (!first)
 292                 return listener_id;
 293
 294         if (name) {
 295                 debug("name_listener_add(%s)", name);
 296
 297                 if (!add_match(connection, name)) {
 298                         name_data_remove(connection, name, listener_id);
 299                         return 0;
 300                 }
 301         }
 302
 303         return listener_id;
 304 }
 305
 306 guint g_dbus_add_disconnect_watch(DBusConnection *connection, const char *name,
 307                                 GDBusWatchFunction func,
 308                                 void *user_data, GDBusDestroyFunction destroy)
 309 {
 310         return g_dbus_add_service_watch(connection, name, NULL, func,
 311                                                         user_data, destroy);
 312 }
 313
 314 guint g_dbus_add_signal_watch(DBusConnection *connection,
 315                                 const char *rule, GDBusSignalFunction function,
 316                                 void *user_data, GDBusDestroyFunction destroy)
 317 {
 318         return 0;
 319 }
 320
 321 gboolean g_dbus_remove_watch(DBusConnection *connection, guint id)
 322 {
 323         struct name_data *data;
 324         struct name_callback *cb;
 325         GSList *ldata, *lcb;
 326
 327         if (id == 0)
 328                 return FALSE;
 329
 330         for (ldata = name_listeners; ldata; ldata = ldata->next) {
 331                 data = ldata->data;
 332                 for (lcb = data->callbacks; lcb; lcb = lcb->next) {
 333                         cb = lcb->data;
 334                         if (cb->id == id)
 335                                 goto remove;
 336                 }
 337         }
 338
 339         return FALSE;
 340
 341 remove:
 342         data->callbacks = g_slist_remove(data->callbacks, cb);
 343         g_free(cb);
 344
 345         /* Don't remove the filter if other callbacks exist */
 346         if (data->callbacks)
 347                 return TRUE;
 348
 349         if (data->name) {
 350                 if (!remove_match(data->connection, data->name))
 351                         return FALSE;
 352         }
 353
 354         name_listeners = g_slist_remove(name_listeners, data);
 355         name_data_free(data);
 356
 357         return TRUE;
 358 }
 359
 360 void g_dbus_remove_all_watches(DBusConnection *connection)
 361 {
 362         struct name_data *data;
 363
 364         data = name_data_find(connection, NULL);
 365         if (!data) {
 366                 error("name_listener_indicate_disconnect: no listener found");
 367                 return;
 368         }
 369
 370         debug("name_listener_indicate_disconnect");
 371
 372         name_data_call_and_free(data);
 373 }