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 struct security_data {
  56         GDBusPendingReply pending;
  57         DBusMessage *message;
  58         const GDBusMethodTable *method;
  59         void *iface_user_data;
  60 };
  61
  62 static void print_arguments(GString *gstr, const char *sig,
  63                                                 const char *direction)
  64 {
  65         int i;
  66
  67         for (i = 0; sig[i]; i++) {
  68                 char type[32];
  69                 int struct_level, dict_level;
  70                 unsigned int len;
  71                 gboolean complete;
  72
  73                 complete = FALSE;
  74                 struct_level = dict_level = 0;
  75                 memset(type, 0, sizeof(type));
  76
  77                 /* Gather enough data to have a single complete type */
  78                 for (len = 0; len < (sizeof(type) - 1) && sig[i]; len++, i++) {
  79                         switch (sig[i]){
  80                         case '(':
  81                                 struct_level++;
  82                                 break;
  83                         case ')':
  84                                 struct_level--;
  85                                 if (struct_level <= 0 && dict_level <= 0)
  86                                         complete = TRUE;
  87                                 break;
  88                         case '{':
  89                                 dict_level++;
  90                                 break;
  91                         case '}':
  92                                 dict_level--;
  93                                 if (struct_level <= 0 && dict_level <= 0)
  94                                         complete = TRUE;
  95                                 break;
  96                         case 'a':
  97                                 break;
  98                         default:
  99                                 if (struct_level <= 0 && dict_level <= 0)
 100                                         complete = TRUE;
 101                                 break;
 102                         }
 103
 104                         type[len] = sig[i];
 105
 106                         if (complete)
 107                                 break;
 108                 }
 109
 110
 111                 if (direction)
 112                         g_string_append_printf(gstr,
 113                                         "\t\t\t<arg type=\"%s\" direction=\"%s\"/>\n",
 114                                         type, direction);
 115                 else
 116                         g_string_append_printf(gstr,
 117                                         "\t\t\t<arg type=\"%s\"/>\n",
 118                                         type);
 119         }
 120 }
 121
 122 static void generate_interface_xml(GString *gstr, struct interface_data *iface)
 123 {
 124         const GDBusMethodTable *method;
 125         const GDBusSignalTable *signal;
 126
 127         for (method = iface->methods; method && method->name; method++) {
 128                 if (!strlen(method->signature) && !strlen(method->reply))
 129                         g_string_append_printf(gstr, "\t\t<method name=\"%s\"/>\n",
 130                                                                 method->name);
 131                 else {
 132                         g_string_append_printf(gstr, "\t\t<method name=\"%s\">\n",
 133                                                                 method->name);
 134                         print_arguments(gstr, method->signature, "in");
 135                         print_arguments(gstr, method->reply, "out");
 136                         g_string_append_printf(gstr, "\t\t</method>\n");
 137                 }
 138         }
 139
 140         for (signal = iface->signals; signal && signal->name; signal++) {
 141                 if (!strlen(signal->signature))
 142                         g_string_append_printf(gstr, "\t\t<signal name=\"%s\"/>\n",
 143                                                                 signal->name);
 144                 else {
 145                         g_string_append_printf(gstr, "\t\t<signal name=\"%s\">\n",
 146                                                                 signal->name);
 147                         print_arguments(gstr, signal->signature, NULL);
 148                         g_string_append_printf(gstr, "\t\t</signal>\n");
 149                 }
 150         }
 151 }
 152
 153 static void generate_introspection_xml(DBusConnection *conn,
 154                                 struct generic_data *data, const char *path)
 155 {
 156         GSList *list;
 157         GString *gstr;
 158         char **children;
 159         int i;
 160
 161         g_free(data->introspect);
 162
 163         gstr = g_string_new(DBUS_INTROSPECT_1_0_XML_DOCTYPE_DECL_NODE);
 164
 165         g_string_append_printf(gstr, "<node name=\"%s\">\n", path);
 166
 167         for (list = data->interfaces; list; list = list->next) {
 168                 struct interface_data *iface = list->data;
 169
 170                 g_string_append_printf(gstr, "\t<interface name=\"%s\">\n",
 171                                                                 iface->name);
 172
 173                 generate_interface_xml(gstr, iface);
 174
 175                 g_string_append_printf(gstr, "\t</interface>\n");
 176         }
 177
 178         if (!dbus_connection_list_registered(conn, path, &children))
 179                 goto done;
 180
 181         for (i = 0; children[i]; i++)
 182                 g_string_append_printf(gstr, "\t<node name=\"%s\"/>\n",
 183                                                                 children[i]);
 184
 185         dbus_free_string_array(children);
 186
 187 done:
 188         g_string_append_printf(gstr, "</node>\n");
 189
 190         data->introspect = g_string_free(gstr, FALSE);
 191 }
 192
 193 static DBusMessage *introspect(DBusConnection *connection,
 194                                 DBusMessage *message, void *user_data)
 195 {
 196         struct generic_data *data = user_data;
 197         DBusMessage *reply;
 198
 199         if (!dbus_message_has_signature(message, DBUS_TYPE_INVALID_AS_STRING)) {
 200                 error("Unexpected signature to introspect call");
 201                 return NULL;
 202         }
 203
 204         if (!data->introspect)
 205                 generate_introspection_xml(connection, data,
 206                                                 dbus_message_get_path(message));
 207
 208         reply = dbus_message_new_method_return(message);
 209         if (!reply)
 210                 return NULL;
 211
 212         dbus_message_append_args(reply, DBUS_TYPE_STRING, &data->introspect,
 213                                         DBUS_TYPE_INVALID);
 214
 215         return reply;
 216 }
 217
 218 static DBusHandlerResult process_message(DBusConnection *connection,
 219                         DBusMessage *message, const GDBusMethodTable *method,
 220                                                         void *iface_user_data)
 221 {
 222         DBusMessage *reply;
 223
 224         reply = method->function(connection, message, iface_user_data);
 225
 226         if (method->flags & G_DBUS_METHOD_FLAG_NOREPLY) {
 227                 if (reply != NULL)
 228                         dbus_message_unref(reply);
 229                 return DBUS_HANDLER_RESULT_HANDLED;
 230         }
 231
 232         if (method->flags & G_DBUS_METHOD_FLAG_ASYNC) {
 233                 if (reply == NULL)
 234                         return DBUS_HANDLER_RESULT_HANDLED;
 235         }
 236
 237         if (reply == NULL)
 238                 return DBUS_HANDLER_RESULT_NEED_MEMORY;
 239
 240         dbus_connection_send(connection, reply, NULL);
 241         dbus_message_unref(reply);
 242
 243         return DBUS_HANDLER_RESULT_HANDLED;
 244 }
 245
 246 static GDBusPendingReply next_pending = 1;
 247 static GSList *pending_security = NULL;
 248
 249 static const GDBusSecurityTable *security_table = NULL;
 250
 251 void g_dbus_pending_success(DBusConnection *connection,
 252                                         GDBusPendingReply pending)
 253 {
 254         GSList *list;
 255
 256         for (list = pending_security; list; list = list->next) {
 257                 struct security_data *secdata = list->data;
 258                 DBusHandlerResult result;
 259
 260                 if (secdata->pending != pending)
 261                         continue;
 262
 263                 pending_security = g_slist_remove(pending_security, secdata);
 264
 265                 result = process_message(connection, secdata->message,
 266                                 secdata->method, secdata->iface_user_data);
 267
 268                 dbus_message_unref(secdata->message);
 269                 g_free(secdata);
 270                 return;
 271         }
 272 }
 273
 274 void g_dbus_pending_error(DBusConnection *connection,
 275                                 GDBusPendingReply pending, DBusMessage *error)
 276 {
 277         GSList *list;
 278
 279         for (list = pending_security; list; list = list->next) {
 280                 struct security_data *secdata = list->data;
 281
 282                 if (secdata->pending != pending)
 283                         continue;
 284
 285                 pending_security = g_slist_remove(pending_security, secdata);
 286
 287                 if (error != NULL) {
 288                         dbus_connection_send(connection, error, NULL);
 289                         dbus_message_unref(error);
 290                 }
 291
 292                 dbus_message_unref(secdata->message);
 293                 g_free(secdata);
 294                 return;
 295         }
 296 }
 297
 298 static gboolean check_privilege(DBusConnection *conn, DBusMessage *msg,
 299                         const GDBusMethodTable *method, void *iface_user_data)
 300 {
 301         const GDBusSecurityTable *security;
 302
 303         for (security = security_table; security && security->function &&
 304                                         security->privilege; security++) {
 305                 struct security_data *secdata;
 306
 307                 if (security->privilege != method->privilege)
 308                         continue;
 309
 310                 secdata = g_new(struct security_data, 1);
 311                 secdata->pending = next_pending++;
 312                 secdata->message = dbus_message_ref(msg);
 313                 secdata->method = method;
 314                 secdata->iface_user_data = iface_user_data;
 315
 316                 pending_security = g_slist_prepend(pending_security, secdata);
 317
 318                 security->function(conn, secdata->message, secdata->pending);
 319
 320                 return TRUE;
 321         }
 322
 323         return FALSE;
 324 }
 325
 326 static void generic_unregister(DBusConnection *connection, void *user_data)
 327 {
 328         struct generic_data *data = user_data;
 329
 330         g_free(data->introspect);
 331         g_free(data);
 332 }
 333
 334 static struct interface_data *find_interface(GSList *interfaces,
 335                                                 const char *name)
 336 {
 337         GSList *list;
 338
 339         if (!name)
 340                 return NULL;
 341
 342         for (list = interfaces; list; list = list->next) {
 343                 struct interface_data *iface = list->data;
 344                 if (!strcmp(name, iface->name))
 345                         return iface;
 346         }
 347
 348         return NULL;
 349 }
 350
 351 static DBusHandlerResult generic_message(DBusConnection *connection,
 352                                         DBusMessage *message, void *user_data)
 353 {
 354         struct generic_data *data = user_data;
 355         struct interface_data *iface;
 356         const GDBusMethodTable *method;
 357         const char *interface;
 358
 359         interface = dbus_message_get_interface(message);
 360
 361         iface = find_interface(data->interfaces, interface);
 362         if (!iface)
 363                 return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 364
 365         for (method = iface->methods; method &&
 366                         method->name && method->function; method++) {
 367                 if (dbus_message_is_method_call(message, iface->name,
 368                                                         method->name) == FALSE)
 369                         continue;
 370
 371                 if (dbus_message_has_signature(message,
 372                                                 method->signature) == FALSE)
 373                         continue;
 374
 375                 if (check_privilege(connection, message, method,
 376                                                 iface->user_data) == TRUE)
 377                         return DBUS_HANDLER_RESULT_HANDLED;
 378
 379                 return process_message(connection, message, method,
 380                                                         iface->user_data);
 381         }
 382
 383         return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
 384 }
 385
 386 static DBusObjectPathVTable generic_table = {
 387         .unregister_function    = generic_unregister,
 388         .message_function       = generic_message,
 389 };
 390
 391 static void invalidate_parent_data(DBusConnection *conn, const char *child_path)
 392 {
 393         struct generic_data *data = NULL;
 394         char *parent_path, *slash;
 395
 396         parent_path = g_strdup(child_path);
 397         slash = strrchr(parent_path, '/');
 398         if (!slash)
 399                 goto done;
 400
 401         if (slash == parent_path && parent_path[1] != '\0')
 402                 parent_path[1] = '\0';
 403         else
 404                 *slash = '\0';
 405
 406         if (!strlen(parent_path))
 407                 goto done;
 408
 409         if (!dbus_connection_get_object_path_data(conn, parent_path,
 410                                                         (void *) &data)) {
 411                 invalidate_parent_data(conn, parent_path);
 412                 goto done;
 413         }
 414
 415         if (!data)
 416                 goto done;
 417
 418         g_free(data->introspect);
 419         data->introspect = NULL;
 420
 421 done:
 422         g_free(parent_path);
 423 }
 424
 425 static GDBusMethodTable introspect_methods[] = {
 426         { "Introspect", "",     "s", introspect },
 427         { }
 428 };
 429
 430 static void add_interface(struct generic_data *data, const char *name,
 431                                 const GDBusMethodTable *methods,
 432                                 const GDBusSignalTable *signals,
 433                                 const GDBusPropertyTable *properties,
 434                                 void *user_data,
 435                                 GDBusDestroyFunction destroy)
 436 {
 437         struct interface_data *iface;
 438
 439         iface = g_new0(struct interface_data, 1);
 440         iface->name = g_strdup(name);
 441         iface->methods = methods;
 442         iface->signals = signals;
 443         iface->properties = properties;
 444         iface->user_data = user_data;
 445         iface->destroy = destroy;
 446
 447         data->interfaces = g_slist_append(data->interfaces, iface);
 448 }
 449
 450 static struct generic_data *object_path_ref(DBusConnection *connection,
 451                                                         const char *path)
 452 {
 453         struct generic_data *data;
 454
 455         if (dbus_connection_get_object_path_data(connection, path,
 456                                                 (void *) &data) == TRUE) {
 457                 if (data != NULL) {
 458                         data->refcount++;
 459                         return data;
 460                 }
 461         }
 462
 463         data = g_new0(struct generic_data, 1);
 464         data->refcount = 1;
 465
 466         data->introspect = g_strdup(DBUS_INTROSPECT_1_0_XML_DOCTYPE_DECL_NODE "<node></node>");
 467
 468         if (!dbus_connection_register_object_path(connection, path,
 469                                                 &generic_table, data)) {
 470                 g_free(data->introspect);
 471                 g_free(data);
 472                 return NULL;
 473         }
 474
 475         invalidate_parent_data(connection, path);
 476
 477         add_interface(data, DBUS_INTERFACE_INTROSPECTABLE,
 478                         introspect_methods, NULL, NULL, data, NULL);
 479
 480         return data;
 481 }
 482
 483 static gboolean remove_interface(struct generic_data *data, const char *name)
 484 {
 485         struct interface_data *iface;
 486
 487         iface = find_interface(data->interfaces, name);
 488         if (!iface)
 489                 return FALSE;
 490
 491         data->interfaces = g_slist_remove(data->interfaces, iface);
 492
 493         if (iface->destroy)
 494                 iface->destroy(iface->user_data);
 495
 496         g_free(iface->name);
 497         g_free(iface);
 498
 499         return TRUE;
 500 }
 501
 502 static void object_path_unref(DBusConnection *connection, const char *path)
 503 {
 504         struct generic_data *data = NULL;
 505
 506         if (dbus_connection_get_object_path_data(connection, path,
 507                                                 (void *) &data) == FALSE)
 508                 return;
 509
 510         if (data == NULL)
 511                 return;
 512
 513         data->refcount--;
 514
 515         if (data->refcount > 0)
 516                 return;
 517
 518         remove_interface(data, DBUS_INTERFACE_INTROSPECTABLE);
 519
 520         invalidate_parent_data(connection, path);
 521
 522         dbus_connection_unregister_object_path(connection, path);
 523 }
 524
 525 static gboolean check_signal(DBusConnection *conn, const char *path,
 526                                 const char *interface, const char *name,
 527                                 const char **args)
 528 {
 529         struct generic_data *data = NULL;
 530         struct interface_data *iface;
 531         const GDBusSignalTable *signal;
 532
 533         *args = NULL;
 534         if (!dbus_connection_get_object_path_data(conn, path,
 535                                         (void *) &data) || !data) {
 536                 error("dbus_connection_emit_signal: path %s isn't registered",
 537                                 path);
 538                 return FALSE;
 539         }
 540
 541         iface = find_interface(data->interfaces, interface);
 542         if (!iface) {
 543                 error("dbus_connection_emit_signal: %s does not implement %s",
 544                                 path, interface);
 545                 return FALSE;
 546         }
 547
 548         for (signal = iface->signals; signal && signal->name; signal++) {
 549                 if (!strcmp(signal->name, name)) {
 550                         *args = signal->signature;
 551                         break;
 552                 }
 553         }
 554
 555         if (!*args) {
 556                 error("No signal named %s on interface %s", name, interface);
 557                 return FALSE;
 558         }
 559
 560         return TRUE;
 561 }
 562
 563 static dbus_bool_t emit_signal_valist(DBusConnection *conn,
 564                                                 const char *path,
 565                                                 const char *interface,
 566                                                 const char *name,
 567                                                 int first,
 568                                                 va_list var_args)
 569 {
 570         DBusMessage *signal;
 571         dbus_bool_t ret;
 572         const char *signature, *args;
 573
 574         if (!check_signal(conn, path, interface, name, &args))
 575                 return FALSE;
 576
 577         signal = dbus_message_new_signal(path, interface, name);
 578         if (!signal) {
 579                 error("Unable to allocate new %s.%s signal", interface,  name);
 580                 return FALSE;
 581         }
 582
 583         ret = dbus_message_append_args_valist(signal, first, var_args);
 584         if (!ret)
 585                 goto fail;
 586
 587         signature = dbus_message_get_signature(signal);
 588         if (strcmp(args, signature) != 0) {
 589                 error("%s.%s: expected signature'%s' but got '%s'",
 590                                 interface, name, args, signature);
 591                 ret = FALSE;
 592                 goto fail;
 593         }
 594
 595         ret = dbus_connection_send(conn, signal, NULL);
 596
 597 fail:
 598         dbus_message_unref(signal);
 599
 600         return ret;
 601 }
 602
 603 gboolean g_dbus_register_interface(DBusConnection *connection,
 604                                         const char *path, const char *name,
 605                                         const GDBusMethodTable *methods,
 606                                         const GDBusSignalTable *signals,
 607                                         const GDBusPropertyTable *properties,
 608                                         void *user_data,
 609                                         GDBusDestroyFunction destroy)
 610 {
 611         struct generic_data *data;
 612
 613         data = object_path_ref(connection, path);
 614         if (data == NULL)
 615                 return FALSE;
 616
 617         if (find_interface(data->interfaces, name)) {
 618                 object_path_unref(connection, path);
 619                 return FALSE;
 620         }
 621
 622         add_interface(data, name, methods, signals,
 623                         properties, user_data, destroy);
 624
 625         g_free(data->introspect);
 626         data->introspect = NULL;
 627
 628         return TRUE;
 629 }
 630
 631 gboolean g_dbus_unregister_interface(DBusConnection *connection,
 632                                         const char *path, const char *name)
 633 {
 634         struct generic_data *data = NULL;
 635
 636         if (!path)
 637                 return FALSE;
 638
 639         if (dbus_connection_get_object_path_data(connection, path,
 640                                                 (void *) &data) == FALSE)
 641                 return FALSE;
 642
 643         if (data == NULL)
 644                 return FALSE;
 645
 646         if (remove_interface(data, name) == FALSE)
 647                 return FALSE;
 648
 649         g_free(data->introspect);
 650         data->introspect = NULL;
 651
 652         object_path_unref(connection, path);
 653
 654         return TRUE;
 655 }
 656
 657 gboolean g_dbus_register_security(const GDBusSecurityTable *security)
 658 {
 659         if (security_table != NULL)
 660                 return FALSE;
 661
 662         security_table = security;
 663
 664         return TRUE;
 665 }
 666
 667 gboolean g_dbus_unregister_security(const GDBusSecurityTable *security)
 668 {
 669         security_table = NULL;
 670
 671         return TRUE;
 672 }
 673
 674 DBusMessage *g_dbus_create_error_valist(DBusMessage *message, const char *name,
 675                                         const char *format, va_list args)
 676 {
 677         char str[1024];
 678
 679         vsnprintf(str, sizeof(str), format, args);
 680
 681         return dbus_message_new_error(message, name, str);
 682 }
 683
 684 DBusMessage *g_dbus_create_error(DBusMessage *message, const char *name,
 685                                                 const char *format, ...)
 686 {
 687         va_list args;
 688         DBusMessage *reply;
 689
 690         va_start(args, format);
 691
 692         reply = g_dbus_create_error_valist(message, name, format, args);
 693
 694         va_end(args);
 695
 696         return reply;
 697 }
 698
 699 DBusMessage *g_dbus_create_reply_valist(DBusMessage *message,
 700                                                 int type, va_list args)
 701 {
 702         DBusMessage *reply;
 703
 704         reply = dbus_message_new_method_return(message);
 705         if (reply == NULL)
 706                 return NULL;
 707
 708         if (dbus_message_append_args_valist(reply, type, args) == FALSE) {
 709                 dbus_message_unref(reply);
 710                 return NULL;
 711         }
 712
 713         return reply;
 714 }
 715
 716 DBusMessage *g_dbus_create_reply(DBusMessage *message, int type, ...)
 717 {
 718         va_list args;
 719         DBusMessage *reply;
 720
 721         va_start(args, type);
 722
 723         reply = g_dbus_create_reply_valist(message, type, args);
 724
 725         va_end(args);
 726
 727         return reply;
 728 }
 729
 730 gboolean g_dbus_send_message(DBusConnection *connection, DBusMessage *message)
 731 {
 732         dbus_bool_t result;
 733
 734         if (dbus_message_get_type(message) == DBUS_MESSAGE_TYPE_METHOD_CALL)
 735                 dbus_message_set_no_reply(message, TRUE);
 736
 737         result = dbus_connection_send(connection, message, NULL);
 738
 739         dbus_message_unref(message);
 740
 741         return result;
 742 }
 743
 744 gboolean g_dbus_send_reply_valist(DBusConnection *connection,
 745                                 DBusMessage *message, int type, va_list args)
 746 {
 747         DBusMessage *reply;
 748
 749         reply = dbus_message_new_method_return(message);
 750         if (reply == NULL)
 751                 return FALSE;
 752
 753         if (dbus_message_append_args_valist(reply, type, args) == FALSE) {
 754                 dbus_message_unref(reply);
 755                 return FALSE;
 756         }
 757
 758         return g_dbus_send_message(connection, reply);
 759 }
 760
 761 gboolean g_dbus_send_reply(DBusConnection *connection,
 762                                 DBusMessage *message, int type, ...)
 763 {
 764         va_list args;
 765         gboolean result;
 766
 767         va_start(args, type);
 768
 769         result = g_dbus_send_reply_valist(connection, message, type, args);
 770
 771         va_end(args);
 772
 773         return result;
 774 }
 775
 776 gboolean g_dbus_emit_signal(DBusConnection *connection,
 777                                 const char *path, const char *interface,
 778                                 const char *name, int type, ...)
 779 {
 780         va_list args;
 781         gboolean result;
 782
 783         va_start(args, type);
 784
 785         result = emit_signal_valist(connection, path, interface,
 786                                                         name, type, args);
 787
 788         va_end(args);
 789
 790         return result;
 791 }
 792
 793 gboolean g_dbus_emit_signal_valist(DBusConnection *connection,
 794                                 const char *path, const char *interface,
 795                                 const char *name, int type, va_list args)
 796 {
 797         return emit_signal_valist(connection, path, interface,
 798                                                         name, type, args);
 799 }