gdbus/object.c

   1 /*
   2  *
   3  *  D-Bus helper library
   4  *
   5  *  Copyright (C) 2004-2010  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 struct generic_data {
  41         unsigned int refcount;
  42         GSList *interfaces;
  43         char *introspect;
  44 };
  45
  46 struct interface_data {
  47         char *name;
  48         const GDBusMethodTable *methods;
  49         const GDBusSignalTable *signals;
  50         const GDBusPropertyTable *properties;
  51         void *user_data;
  52         GDBusDestroyFunction destroy;
  53 };
  54
  55 static void print_arguments(GString *gstr, const char *sig,
  56                                                 const char *direction)
  57 {
  58         int i;
  59
  60         for (i = 0; sig[i]; i++) {
  61                 char type[32];
  62                 int struct_level, dict_level;
  63                 unsigned int len;
  64                 gboolean complete;
  65
  66                 complete = FALSE;
  67                 struct_level = dict_level = 0;
  68                 memset(type, 0, sizeof(type));
  69
  70                 /* Gather enough data to have a single complete type */
  71                 for (len = 0; len < (sizeof(type) - 1) && sig[i]; len++, i++) {
  72                         switch (sig[i]){
  73                         case '(':
  74                                 struct_level++;
  75                                 break;
  76                         case ')':
  77                                 struct_level--;
  78                                 if (struct_level <= 0 && dict_level <= 0)
  79                                         complete = TRUE;
  80                                 break;
  81                         case '{':
  82                                 dict_level++;
  83                                 break;
  84                         case '}':
  85                                 dict_level--;
  86                                 if (struct_level <= 0 && dict_level <= 0)
  87                                         complete = TRUE;
  88                                 break;
  89                         case 'a':
  90                                 break;
  91                         default:
  92                                 if (struct_level <= 0 && dict_level <= 0)
  93                                         complete = TRUE;
  94                                 break;
  95                         }
  96
  97                         type[len] = sig[i];
  98
  99                         if (complete)
 100                                 break;
 101                 }
 102
 103
 104                 if (direction)
 105                         g_string_append_printf(gstr,
 106                                         "\t\t\t<arg type=\"%s\" direction=\"%s\"/>\n",
 107                                         type, direction);
 108                 else
 109                         g_string_append_printf(gstr,
 110                                         "\t\t\t<arg type=\"%s\"/>\n",
 111                                         type);
 112         }
 113 }
 114
 115 static void generate_interface_xml(GString *gstr, struct interface_data *iface)
 116 {
 117         const GDBusMethodTable *method;
 118         const GDBusSignalTable *signal;
 119
 120         for (method = iface->methods; method && method->name; method++) {
 121                 if (!strlen(method->signature) && !strlen(method->reply))
 122                         g_string_append_printf(gstr, "\t\t<method name=\"%s\"/>\n",
 123                                                                 method->name);
 124                 else {
 125                         g_string_append_printf(gstr, "\t\t<method name=\"%s\">\n",
 126                                                                 method->name);
 127                         print_arguments(gstr, method->signature, "in");
 128                         print_arguments(gstr, method->reply, "out");
 129                         g_string_append_printf(gstr, "\t\t</method>\n");
 130                 }
 131         }
 132
 133         for (signal = iface->signals; signal && signal->name; signal++) {
 134                 if (!strlen(signal->signature))
 135                         g_string_append_printf(gstr, "\t\t<signal name=\"%s\"/>\n",
 136                                                                 signal->name);
 137                 else {
 138                         g_string_append_printf(gstr, "\t\t<signal name=\"%s\">\n",
 139                                                                 signal->name);
 140                         print_arguments(gstr, signal->signature, NULL);
 141                         g_string_append_printf(gstr, "\t\t</signal>\n");
 142                 }
 143         }
 144 }
 145
 146 static void generate_introspection_xml(DBusConnection *conn,
 147                                 struct generic_data *data, const char *path)
 148 {
 149         GSList *list;
 150         GString *gstr;
 151         char **children;
 152         int i;
 153
 154         g_free(data->introspect);
 155
 156         gstr = g_string_new(DBUS_INTROSPECT_1_0_XML_DOCTYPE_DECL_NODE);
 157
 158         g_string_append_printf(gstr, "<node name=\"%s\">\n", path);
 159
 160         for (list = data->interfaces; list; list = list->next) {
 161                 struct interface_data *iface = list->data;
 162
 163                 g_string_append_printf(gstr, "\t<interface name=\"%s\">\n",
 164                                                                 iface->name);
 165
 166                 generate_interface_xml(gstr, iface);
 167
 168                 g_string_append_printf(gstr, "\t</interface>\n");
 169         }
 170
 171         if (!dbus_connection_list_registered(conn, path, &children))
 172                 goto done;
 173
 174         for (i = 0; children[i]; i++)
 175                 g_string_append_printf(gstr, "\t<node name=\"%s\"/>\n",
 176                                                                 children[i]);
 177
 178         dbus_free_string_array(children);
 179
 180 done:
 181         g_string_append_printf(gstr, "</node>\n");
 182
 183         data->introspect = g_string_free(gstr, FALSE);
 184 }
 185
 186 static DBusMessage *introspect(DBusConnection *connection,
 187                                 DBusMessage *message, void *user_data)
 188 {
 189         struct generic_data *data = user_data;
 190         DBusMessage *reply;
 191
 192         if (!dbus_message_has_signature(message, DBUS_TYPE_INVALID_AS_STRING)) {
 193                 error("Unexpected signature to introspect call");
 194                 return NULL;
 195         }
 196
 197         if (!data->introspect)
 198                 generate_introspection_xml(connection, data,
 199                                                 dbus_message_get_path(message));
 200
 201         reply = dbus_message_new_method_return(message);
 202         if (!reply)
 203                 return NULL;
 204
 205         dbus_message_append_args(reply, DBUS_TYPE_STRING, &data->introspect,
 206                                         DBUS_TYPE_INVALID);
 207
 208         return reply;
 209 }
 210
 211 static void generic_unregister(DBusConnection *connection, void *user_data)
 212 {
 213         struct generic_data *data = user_data;
 214
 215         g_free(data->introspect);
 216         g_free(data);
 217 }
 218
 219 static struct interface_data *find_interface(GSList *interfaces,
 220                                                 const char *name)
 221 {
 222         GSList *list;
 223
 224         if (!name)
 225                 return NULL;
 226
 227         for (list = interfaces; list; list = list->next) {
 228                 struct interface_data *iface = list->data;
 229                 if (!strcmp(name, iface->name))
 230                         return iface;
 231         }
 232
 233         return NULL;
 234 }
 235
 236 static DBusHandlerResult generic_message(DBusConnection *connection,
 237                                         DBusMessage *message, void *user_data)
 238 {
 239         struct generic_data *data = user_data;
 240         struct interface_data *iface;
 241         const GDBusMethodTable *method;
 242         const char *interface;
 243
 244         interface = dbus_message_get_interface(message);
 245
 246         iface = find_interface(data->interfaces, interface);
 247         if (!iface)
 248                 return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 249
 250         for (method = iface->methods; method &&
 251                         method->name && method->function; method++) {
 252                 DBusMessage *reply;
 253
 254                 if (dbus_message_is_method_call(message, iface->name,
 255                                                         method->name) == FALSE)
 256                         continue;
 257
 258                 if (dbus_message_has_signature(message,
 259                                                 method->signature) == FALSE)
 260                         continue;
 261
 262                 reply = method->function(connection, message, iface->user_data);
 263
 264                 if (method->flags & G_DBUS_METHOD_FLAG_NOREPLY) {
 265                         if (reply != NULL)
 266                                 dbus_message_unref(reply);
 267                         return DBUS_HANDLER_RESULT_HANDLED;
 268                 }
 269
 270                 if (method->flags & G_DBUS_METHOD_FLAG_ASYNC) {
 271                         if (reply == NULL)
 272                                 return DBUS_HANDLER_RESULT_HANDLED;
 273                 }
 274
 275                 if (reply == NULL)
 276                         return DBUS_HANDLER_RESULT_NEED_MEMORY;
 277
 278                 dbus_connection_send(connection, reply, NULL);
 279                 dbus_message_unref(reply);
 280
 281                 return DBUS_HANDLER_RESULT_HANDLED;
 282         }
 283
 284         return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 285 }
 286
 287 static DBusObjectPathVTable generic_table = {
 288         .unregister_function    = generic_unregister,
 289         .message_function       = generic_message,
 290 };
 291
 292 static void invalidate_parent_data(DBusConnection *conn, const char *child_path)
 293 {
 294         struct generic_data *data = NULL;
 295         char *parent_path, *slash;
 296
 297         parent_path = g_strdup(child_path);
 298         slash = strrchr(parent_path, '/');
 299         if (!slash)
 300                 goto done;
 301
 302         if (slash == parent_path && parent_path[1] != '\0')
 303                 parent_path[1] = '\0';
 304         else
 305                 *slash = '\0';
 306
 307         if (!strlen(parent_path))
 308                 goto done;
 309
 310         if (!dbus_connection_get_object_path_data(conn, parent_path,
 311                                                         (void *) &data))
 312                 goto done;
 313
 314         if (!data)
 315                 goto done;
 316
 317         g_free(data->introspect);
 318         data->introspect = NULL;
 319
 320 done:
 321         g_free(parent_path);
 322 }
 323
 324 static GDBusMethodTable introspect_methods[] = {
 325         { "Introspect", "",     "s", introspect },
 326         { }
 327 };
 328
 329 static void add_interface(struct generic_data *data, const char *name,
 330                                 const GDBusMethodTable *methods,
 331                                 const GDBusSignalTable *signals,
 332                                 const GDBusPropertyTable *properties,
 333                                 void *user_data,
 334                                 GDBusDestroyFunction destroy)
 335 {
 336         struct interface_data *iface;
 337
 338         iface = g_new0(struct interface_data, 1);
 339         iface->name = g_strdup(name);
 340         iface->methods = methods;
 341         iface->signals = signals;
 342         iface->properties = properties;
 343         iface->user_data = user_data;
 344         iface->destroy = destroy;
 345
 346         data->interfaces = g_slist_append(data->interfaces, iface);
 347 }
 348
 349 static struct generic_data *object_path_ref(DBusConnection *connection,
 350                                                         const char *path)
 351 {
 352         struct generic_data *data;
 353
 354         if (dbus_connection_get_object_path_data(connection, path,
 355                                                 (void *) &data) == TRUE) {
 356                 if (data != NULL) {
 357                         data->refcount++;
 358                         return data;
 359                 }
 360         }
 361
 362         data = g_new0(struct generic_data, 1);
 363
 364         data->introspect = g_strdup(DBUS_INTROSPECT_1_0_XML_DOCTYPE_DECL_NODE "<node></node>");
 365
 366         data->refcount = 1;
 367
 368         if (!dbus_connection_register_object_path(connection, path,
 369                                                 &generic_table, data)) {
 370                 g_free(data->introspect);
 371                 g_free(data);
 372                 return NULL;
 373         }
 374
 375         invalidate_parent_data(connection, path);
 376
 377         add_interface(data, DBUS_INTERFACE_INTROSPECTABLE,
 378                         introspect_methods, NULL, NULL, data, NULL);
 379
 380         return data;
 381 }
 382
 383 static gboolean remove_interface(struct generic_data *data, const char *name)
 384 {
 385         struct interface_data *iface;
 386
 387         iface = find_interface(data->interfaces, name);
 388         if (!iface)
 389                 return FALSE;
 390
 391         data->interfaces = g_slist_remove(data->interfaces, iface);
 392
 393         if (iface->destroy)
 394                 iface->destroy(iface->user_data);
 395
 396         g_free(iface->name);
 397         g_free(iface);
 398
 399         return TRUE;
 400 }
 401
 402 static void object_path_unref(DBusConnection *connection, const char *path)
 403 {
 404         struct generic_data *data = NULL;
 405
 406         if (dbus_connection_get_object_path_data(connection, path,
 407                                                 (void *) &data) == FALSE)
 408                 return;
 409
 410         if (data == NULL)
 411                 return;
 412
 413         data->refcount--;
 414
 415         if (data->refcount > 0)
 416                 return;
 417
 418         remove_interface(data, DBUS_INTERFACE_INTROSPECTABLE);
 419
 420         invalidate_parent_data(connection, path);
 421
 422         dbus_connection_unregister_object_path(connection, path);
 423 }
 424
 425 static gboolean check_signal(DBusConnection *conn, const char *path,
 426                                 const char *interface, const char *name,
 427                                 const char **args)
 428 {
 429         struct generic_data *data = NULL;
 430         struct interface_data *iface;
 431         const GDBusSignalTable *signal;
 432
 433         *args = NULL;
 434         if (!dbus_connection_get_object_path_data(conn, path,
 435                                         (void *) &data) || !data) {
 436                 error("dbus_connection_emit_signal: path %s isn't registered",
 437                                 path);
 438                 return FALSE;
 439         }
 440
 441         iface = find_interface(data->interfaces, interface);
 442         if (!iface) {
 443                 error("dbus_connection_emit_signal: %s does not implement %s",
 444                                 path, interface);
 445                 return FALSE;
 446         }
 447
 448         for (signal = iface->signals; signal && signal->name; signal++) {
 449                 if (!strcmp(signal->name, name)) {
 450                         *args = signal->signature;
 451                         break;
 452                 }
 453         }
 454
 455         if (!*args) {
 456                 error("No signal named %s on interface %s", name, interface);
 457                 return FALSE;
 458         }
 459
 460         return TRUE;
 461 }
 462
 463 static dbus_bool_t emit_signal_valist(DBusConnection *conn,
 464                                                 const char *path,
 465                                                 const char *interface,
 466                                                 const char *name,
 467                                                 int first,
 468                                                 va_list var_args)
 469 {
 470         DBusMessage *signal;
 471         dbus_bool_t ret;
 472         const char *signature, *args;
 473
 474         if (!check_signal(conn, path, interface, name, &args))
 475                 return FALSE;
 476
 477         signal = dbus_message_new_signal(path, interface, name);
 478         if (!signal) {
 479                 error("Unable to allocate new %s.%s signal", interface,  name);
 480                 return FALSE;
 481         }
 482
 483         ret = dbus_message_append_args_valist(signal, first, var_args);
 484         if (!ret)
 485                 goto fail;
 486
 487         signature = dbus_message_get_signature(signal);
 488         if (strcmp(args, signature) != 0) {
 489                 error("%s.%s: expected signature'%s' but got '%s'",
 490                                 interface, name, args, signature);
 491                 ret = FALSE;
 492                 goto fail;
 493         }
 494
 495         ret = dbus_connection_send(conn, signal, NULL);
 496
 497 fail:
 498         dbus_message_unref(signal);
 499
 500         return ret;
 501 }
 502
 503 gboolean g_dbus_register_interface(DBusConnection *connection,
 504                                         const char *path, const char *name,
 505                                         const GDBusMethodTable *methods,
 506                                         const GDBusSignalTable *signals,
 507                                         const GDBusPropertyTable *properties,
 508                                         void *user_data,
 509                                         GDBusDestroyFunction destroy)
 510 {
 511         struct generic_data *data;
 512
 513         data = object_path_ref(connection, path);
 514         if (data == NULL)
 515                 return FALSE;
 516
 517         if (find_interface(data->interfaces, name))
 518                 return FALSE;
 519
 520         add_interface(data, name, methods, signals,
 521                         properties, user_data, destroy);
 522
 523         g_free(data->introspect);
 524         data->introspect = NULL;
 525
 526         return TRUE;
 527 }
 528
 529 gboolean g_dbus_unregister_interface(DBusConnection *connection,
 530                                         const char *path, const char *name)
 531 {
 532         struct generic_data *data = NULL;
 533
 534         if (!path)
 535                 return FALSE;
 536
 537         if (dbus_connection_get_object_path_data(connection, path,
 538                                                 (void *) &data) == FALSE)
 539                 return FALSE;
 540
 541         if (data == NULL)
 542                 return FALSE;
 543
 544         if (remove_interface(data, name) == FALSE)
 545                 return FALSE;
 546
 547         g_free(data->introspect);
 548         data->introspect = NULL;
 549
 550         object_path_unref(connection, path);
 551
 552         return TRUE;
 553 }
 554
 555 DBusMessage *g_dbus_create_error_valist(DBusMessage *message, const char *name,
 556                                         const char *format, va_list args)
 557 {
 558         char str[1024];
 559
 560         vsnprintf(str, sizeof(str), format, args);
 561
 562         return dbus_message_new_error(message, name, str);
 563 }
 564
 565 DBusMessage *g_dbus_create_error(DBusMessage *message, const char *name,
 566                                                 const char *format, ...)
 567 {
 568         va_list args;
 569         DBusMessage *reply;
 570
 571         va_start(args, format);
 572
 573         reply = g_dbus_create_error_valist(message, name, format, args);
 574
 575         va_end(args);
 576
 577         return reply;
 578 }
 579
 580 DBusMessage *g_dbus_create_reply_valist(DBusMessage *message,
 581                                                 int type, va_list args)
 582 {
 583         DBusMessage *reply;
 584
 585         reply = dbus_message_new_method_return(message);
 586         if (reply == NULL)
 587                 return NULL;
 588
 589         if (dbus_message_append_args_valist(reply, type, args) == FALSE) {
 590                 dbus_message_unref(reply);
 591                 return NULL;
 592         }
 593
 594         return reply;
 595 }
 596
 597 DBusMessage *g_dbus_create_reply(DBusMessage *message, int type, ...)
 598 {
 599         va_list args;
 600         DBusMessage *reply;
 601
 602         va_start(args, type);
 603
 604         reply = g_dbus_create_reply_valist(message, type, args);
 605
 606         va_end(args);
 607
 608         return reply;
 609 }
 610
 611 gboolean g_dbus_send_message(DBusConnection *connection, DBusMessage *message)
 612 {
 613         dbus_bool_t result;
 614
 615         if (dbus_message_get_type(message) == DBUS_MESSAGE_TYPE_METHOD_CALL)
 616                 dbus_message_set_no_reply(message, TRUE);
 617
 618         result = dbus_connection_send(connection, message, NULL);
 619
 620         dbus_message_unref(message);
 621
 622         return result;
 623 }
 624
 625 gboolean g_dbus_send_reply_valist(DBusConnection *connection,
 626                                 DBusMessage *message, int type, va_list args)
 627 {
 628         DBusMessage *reply;
 629
 630         reply = dbus_message_new_method_return(message);
 631         if (reply == NULL)
 632                 return FALSE;
 633
 634         if (dbus_message_append_args_valist(reply, type, args) == FALSE) {
 635                 dbus_message_unref(reply);
 636                 return FALSE;
 637         }
 638
 639         return g_dbus_send_message(connection, reply);
 640 }
 641
 642 gboolean g_dbus_send_reply(DBusConnection *connection,
 643                                 DBusMessage *message, int type, ...)
 644 {
 645         va_list args;
 646         gboolean result;
 647
 648         va_start(args, type);
 649
 650         result = g_dbus_send_reply_valist(connection, message, type, args);
 651
 652         va_end(args);
 653
 654         return result;
 655 }
 656
 657 gboolean g_dbus_emit_signal(DBusConnection *connection,
 658                                 const char *path, const char *interface,
 659                                 const char *name, int type, ...)
 660 {
 661         va_list args;
 662         gboolean result;
 663
 664         va_start(args, type);
 665
 666         result = emit_signal_valist(connection, path, interface,
 667                                                         name, type, args);
 668
 669         va_end(args);
 670
 671         return result;
 672 }
 673
 674 gboolean g_dbus_emit_signal_valist(DBusConnection *connection,
 675                                 const char *path, const char *interface,
 676                                 const char *name, int type, va_list args)
 677 {
 678         return emit_signal_valist(connection, path, interface,
 679                                                         name, type, args);
 680 }