gio/gdbusprivate.c

   1 /* GDBus - GLib D-Bus Library
   2  *
   3  * Copyright (C) 2008-2010 Red Hat, Inc.
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General
  16  * Public License along with this library; if not, write to the
  17  * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  18  * Boston, MA 02111-1307, USA.
  19  *
  20  * Author: David Zeuthen <davidz@redhat.com>
  21  */
  22
  23 #include "config.h"
  24
  25 #include <stdlib.h>
  26 #include <string.h>
  27 #ifdef HAVE_UNISTD_H
  28 #include <unistd.h>
  29 #endif
  30
  31 #include "giotypes.h"
  32 #include "gsocket.h"
  33 #include "gdbusprivate.h"
  34 #include "gdbusmessage.h"
  35 #include "gdbuserror.h"
  36 #include "gdbusintrospection.h"
  37 #include "gasyncresult.h"
  38 #include "gsimpleasyncresult.h"
  39 #include "ginputstream.h"
  40 #include "giostream.h"
  41 #include "gsocketcontrolmessage.h"
  42 #include "gsocketconnection.h"
  43
  44 #ifdef G_OS_UNIX
  45 #include "gunixfdmessage.h"
  46 #include "gunixconnection.h"
  47 #include "gunixcredentialsmessage.h"
  48 #endif
  49
  50 #ifdef G_OS_WIN32
  51 #include <windows.h>
  52 #endif
  53
  54 #include "glibintl.h"
  55 #include "gioalias.h"
  56
  57 /* ---------------------------------------------------------------------------------------------------- */
  58
  59 gchar *
  60 _g_dbus_hexdump (const gchar *data, gsize len, guint indent)
  61 {
  62  guint n, m;
  63  GString *ret;
  64
  65  ret = g_string_new (NULL);
  66
  67  for (n = 0; n < len; n += 16)
  68    {
  69      g_string_append_printf (ret, "%*s%04x: ", indent, "", n);
  70
  71      for (m = n; m < n + 16; m++)
  72        {
  73          if (m > n && (m%4) == 0)
  74            g_string_append_c (ret, ' ');
  75          if (m < len)
  76            g_string_append_printf (ret, "%02x ", (guchar) data[m]);
  77          else
  78            g_string_append (ret, "   ");
  79        }
  80
  81      g_string_append (ret, "   ");
  82
  83      for (m = n; m < len && m < n + 16; m++)
  84        g_string_append_c (ret, g_ascii_isprint (data[m]) ? data[m] : '.');
  85
  86      g_string_append_c (ret, '\n');
  87    }
  88
  89  return g_string_free (ret, FALSE);
  90 }
  91
  92 /* ---------------------------------------------------------------------------------------------------- */
  93
  94 /* Unfortunately ancillary messages are discarded when reading from a
  95  * socket using the GSocketInputStream abstraction. So we provide a
  96  * very GInputStream-ish API that uses GSocket in this case (very
  97  * similar to GSocketInputStream).
  98  */
  99
 100 typedef struct
 101 {
 102   GSocket *socket;
 103   GCancellable *cancellable;
 104
 105   void *buffer;
 106   gsize count;
 107
 108   GSocketControlMessage ***messages;
 109   gint *num_messages;
 110
 111   GSimpleAsyncResult *simple;
 112
 113   gboolean from_mainloop;
 114 } ReadWithControlData;
 115
 116 static void
 117 read_with_control_data_free (ReadWithControlData *data)
 118 {
 119   g_object_unref (data->socket);
 120   if (data->cancellable != NULL)
 121     g_object_unref (data->cancellable);
 122   g_free (data);
 123 }
 124
 125 static gboolean
 126 _g_socket_read_with_control_messages_ready (GSocket      *socket,
 127                                             GIOCondition  condition,
 128                                             gpointer      user_data)
 129 {
 130   ReadWithControlData *data = user_data;
 131   GError *error;
 132   gssize result;
 133   GInputVector vector;
 134
 135   error = NULL;
 136   vector.buffer = data->buffer;
 137   vector.size = data->count;
 138   result = g_socket_receive_message (data->socket,
 139                                      NULL, /* address */
 140                                      &vector,
 141                                      1,
 142                                      data->messages,
 143                                      data->num_messages,
 144                                      NULL,
 145                                      data->cancellable,
 146                                      &error);
 147   if (result >= 0)
 148     {
 149       g_simple_async_result_set_op_res_gssize (data->simple, result);
 150     }
 151   else
 152     {
 153       g_assert (error != NULL);
 154       g_simple_async_result_set_from_error (data->simple, error);
 155       g_error_free (error);
 156     }
 157
 158   if (data->from_mainloop)
 159     g_simple_async_result_complete (data->simple);
 160   else
 161     g_simple_async_result_complete_in_idle (data->simple);
 162
 163   return FALSE;
 164 }
 165
 166 static void
 167 _g_socket_read_with_control_messages (GSocket                 *socket,
 168                                       void                    *buffer,
 169                                       gsize                    count,
 170                                       GSocketControlMessage ***messages,
 171                                       gint                    *num_messages,
 172                                       gint                     io_priority,
 173                                       GCancellable            *cancellable,
 174                                       GAsyncReadyCallback      callback,
 175                                       gpointer                 user_data)
 176 {
 177   ReadWithControlData *data;
 178
 179   data = g_new0 (ReadWithControlData, 1);
 180   data->socket = g_object_ref (socket);
 181   data->cancellable = cancellable != NULL ? g_object_ref (cancellable) : NULL;
 182   data->buffer = buffer;
 183   data->count = count;
 184   data->messages = messages;
 185   data->num_messages = num_messages;
 186
 187   data->simple = g_simple_async_result_new (G_OBJECT (socket),
 188                                             callback,
 189                                             user_data,
 190                                             _g_socket_read_with_control_messages);
 191
 192   if (!g_socket_condition_check (socket, G_IO_IN))
 193     {
 194       GSource *source;
 195       data->from_mainloop = TRUE;
 196       source = g_socket_create_source (data->socket,
 197                                        G_IO_IN | G_IO_HUP | G_IO_ERR,
 198                                        cancellable);
 199       g_source_set_callback (source,
 200                              (GSourceFunc) _g_socket_read_with_control_messages_ready,
 201                              data,
 202                              (GDestroyNotify) read_with_control_data_free);
 203       g_source_attach (source, g_main_context_get_thread_default ());
 204       g_source_unref (source);
 205     }
 206   else
 207     {
 208       _g_socket_read_with_control_messages_ready (data->socket, G_IO_IN, data);
 209       read_with_control_data_free (data);
 210     }
 211 }
 212
 213 static gssize
 214 _g_socket_read_with_control_messages_finish (GSocket       *socket,
 215                                              GAsyncResult  *result,
 216                                              GError       **error)
 217 {
 218   GSimpleAsyncResult *simple = G_SIMPLE_ASYNC_RESULT (result);
 219
 220   g_return_val_if_fail (G_IS_SOCKET (socket), -1);
 221   g_warn_if_fail (g_simple_async_result_get_source_tag (simple) == _g_socket_read_with_control_messages);
 222
 223   if (g_simple_async_result_propagate_error (simple, error))
 224       return -1;
 225   else
 226     return g_simple_async_result_get_op_res_gssize (simple);
 227 }
 228
 229 /* ---------------------------------------------------------------------------------------------------- */
 230
 231 G_LOCK_DEFINE_STATIC (shared_thread_lock);
 232
 233 typedef struct
 234 {
 235   gint num_users;
 236   GThread *thread;
 237   GMainContext *context;
 238   GMainLoop *loop;
 239 } SharedThreadData;
 240
 241 static SharedThreadData *shared_thread_data = NULL;
 242
 243 static gpointer
 244 shared_thread_func (gpointer data)
 245 {
 246   g_main_context_push_thread_default (shared_thread_data->context);
 247   g_main_loop_run (shared_thread_data->loop);
 248   g_main_context_pop_thread_default (shared_thread_data->context);
 249   return NULL;
 250 }
 251
 252 typedef void (*GDBusSharedThreadFunc) (gpointer user_data);
 253
 254 typedef struct
 255 {
 256   GDBusSharedThreadFunc func;
 257   gpointer              user_data;
 258   gboolean              done;
 259 } CallerData;
 260
 261 static gboolean
 262 invoke_caller (gpointer user_data)
 263 {
 264   CallerData *data = user_data;
 265   data->func (data->user_data);
 266   data->done = TRUE;
 267   return FALSE;
 268 }
 269
 270 static void
 271 _g_dbus_shared_thread_ref (GDBusSharedThreadFunc func,
 272                            gpointer              user_data)
 273 {
 274   GError *error;
 275   GSource *idle_source;
 276   CallerData *data;
 277
 278   G_LOCK (shared_thread_lock);
 279
 280   if (shared_thread_data != NULL)
 281     {
 282       shared_thread_data->num_users += 1;
 283       goto have_thread;
 284     }
 285
 286   shared_thread_data = g_new0 (SharedThreadData, 1);
 287   shared_thread_data->num_users = 1;
 288
 289   error = NULL;
 290   shared_thread_data->context = g_main_context_new ();
 291   shared_thread_data->loop = g_main_loop_new (shared_thread_data->context, FALSE);
 292   shared_thread_data->thread = g_thread_create (shared_thread_func,
 293                                                 NULL,
 294                                                 TRUE,
 295                                                 &error);
 296   g_assert_no_error (error);
 297
 298  have_thread:
 299
 300   data = g_new0 (CallerData, 1);
 301   data->func = func;
 302   data->user_data = user_data;
 303   data->done = FALSE;
 304
 305   idle_source = g_idle_source_new ();
 306   g_source_set_priority (idle_source, G_PRIORITY_DEFAULT);
 307   g_source_set_callback (idle_source,
 308                          invoke_caller,
 309                          data,
 310                          NULL);
 311   g_source_attach (idle_source, shared_thread_data->context);
 312   g_source_unref (idle_source);
 313
 314   /* wait for the user code to run.. hmm.. probably use a condition variable instead */
 315   while (!data->done)
 316     g_thread_yield ();
 317
 318   g_free (data);
 319
 320   G_UNLOCK (shared_thread_lock);
 321 }
 322
 323 static void
 324 _g_dbus_shared_thread_unref (void)
 325 {
 326   /* TODO: actually destroy the shared thread here */
 327 #if 0
 328   G_LOCK (shared_thread_lock);
 329   g_assert (shared_thread_data != NULL);
 330   shared_thread_data->num_users -= 1;
 331   if (shared_thread_data->num_users == 0)
 332     {
 333       g_main_loop_quit (shared_thread_data->loop);
 334       //g_thread_join (shared_thread_data->thread);
 335       g_main_loop_unref (shared_thread_data->loop);
 336       g_main_context_unref (shared_thread_data->context);
 337       g_free (shared_thread_data);
 338       shared_thread_data = NULL;
 339       G_UNLOCK (shared_thread_lock);
 340     }
 341   else
 342     {
 343       G_UNLOCK (shared_thread_lock);
 344     }
 345 #endif
 346 }
 347
 348 /* ---------------------------------------------------------------------------------------------------- */
 349
 350 struct GDBusWorker
 351 {
 352   volatile gint                       ref_count;
 353   gboolean                            stopped;
 354   GIOStream                          *stream;
 355   GDBusCapabilityFlags                capabilities;
 356   GCancellable                       *cancellable;
 357   GDBusWorkerMessageReceivedCallback  message_received_callback;
 358   GDBusWorkerMessageAboutToBeSentCallback message_about_to_be_sent_callback;
 359   GDBusWorkerDisconnectedCallback     disconnected_callback;
 360   gpointer                            user_data;
 361
 362   GThread                            *thread;
 363
 364   /* if not NULL, stream is GSocketConnection */
 365   GSocket *socket;
 366
 367   /* used for reading */
 368   GMutex                             *read_lock;
 369   gchar                              *read_buffer;
 370   gsize                               read_buffer_allocated_size;
 371   gsize                               read_buffer_cur_size;
 372   gsize                               read_buffer_bytes_wanted;
 373   GUnixFDList                        *read_fd_list;
 374   GSocketControlMessage             **read_ancillary_messages;
 375   gint                                read_num_ancillary_messages;
 376
 377   /* used for writing */
 378   GMutex                             *write_lock;
 379   GQueue                             *write_queue;
 380   gboolean                            write_is_pending;
 381 };
 382
 383 struct _MessageToWriteData ;
 384 typedef struct _MessageToWriteData MessageToWriteData;
 385
 386 static void message_to_write_data_free (MessageToWriteData *data);
 387
 388 static GDBusWorker *
 389 _g_dbus_worker_ref (GDBusWorker *worker)
 390 {
 391   g_atomic_int_inc (&worker->ref_count);
 392   return worker;
 393 }
 394
 395 static void
 396 _g_dbus_worker_unref (GDBusWorker *worker)
 397 {
 398   if (g_atomic_int_dec_and_test (&worker->ref_count))
 399     {
 400       _g_dbus_shared_thread_unref ();
 401
 402       g_object_unref (worker->stream);
 403
 404       g_mutex_free (worker->read_lock);
 405       g_object_unref (worker->cancellable);
 406       if (worker->read_fd_list != NULL)
 407         g_object_unref (worker->read_fd_list);
 408
 409       g_mutex_free (worker->write_lock);
 410       g_queue_foreach (worker->write_queue,
 411                        (GFunc) message_to_write_data_free,
 412                        NULL);
 413       g_queue_free (worker->write_queue);
 414       g_free (worker);
 415     }
 416 }
 417
 418 static void
 419 _g_dbus_worker_emit_disconnected (GDBusWorker  *worker,
 420                                   gboolean      remote_peer_vanished,
 421                                   GError       *error)
 422 {
 423   if (!worker->stopped)
 424     worker->disconnected_callback (worker, remote_peer_vanished, error, worker->user_data);
 425 }
 426
 427 static void
 428 _g_dbus_worker_emit_message_received (GDBusWorker  *worker,
 429                                       GDBusMessage *message)
 430 {
 431   if (!worker->stopped)
 432     worker->message_received_callback (worker, message, worker->user_data);
 433 }
 434
 435 static gboolean
 436 _g_dbus_worker_emit_message_about_to_be_sent (GDBusWorker  *worker,
 437                                               GDBusMessage *message)
 438 {
 439   gboolean ret;
 440   ret = FALSE;
 441   if (!worker->stopped)
 442     ret = worker->message_about_to_be_sent_callback (worker, message, worker->user_data);
 443   return ret;
 444 }
 445
 446 static void _g_dbus_worker_do_read_unlocked (GDBusWorker *worker);
 447
 448 /* called in private thread shared by all GDBusConnection instances (without read-lock held) */
 449 static void
 450 _g_dbus_worker_do_read_cb (GInputStream  *input_stream,
 451                            GAsyncResult  *res,
 452                            gpointer       user_data)
 453 {
 454   GDBusWorker *worker = user_data;
 455   GError *error;
 456   gssize bytes_read;
 457
 458   g_mutex_lock (worker->read_lock);
 459
 460   /* If already stopped, don't even process the reply */
 461   if (worker->stopped)
 462     goto out;
 463
 464   error = NULL;
 465   if (worker->socket == NULL)
 466     bytes_read = g_input_stream_read_finish (g_io_stream_get_input_stream (worker->stream),
 467                                              res,
 468                                              &error);
 469   else
 470     bytes_read = _g_socket_read_with_control_messages_finish (worker->socket,
 471                                                               res,
 472                                                               &error);
 473   if (worker->read_num_ancillary_messages > 0)
 474     {
 475       gint n;
 476       for (n = 0; n < worker->read_num_ancillary_messages; n++)
 477         {
 478           GSocketControlMessage *control_message = G_SOCKET_CONTROL_MESSAGE (worker->read_ancillary_messages[n]);
 479
 480           if (FALSE)
 481             {
 482             }
 483 #ifdef G_OS_UNIX
 484           else if (G_IS_UNIX_FD_MESSAGE (control_message))
 485             {
 486               GUnixFDMessage *fd_message;
 487               gint *fds;
 488               gint num_fds;
 489
 490               fd_message = G_UNIX_FD_MESSAGE (control_message);
 491               fds = g_unix_fd_message_steal_fds (fd_message, &num_fds);
 492               if (worker->read_fd_list == NULL)
 493                 {
 494                   worker->read_fd_list = g_unix_fd_list_new_from_array (fds, num_fds);
 495                 }
 496               else
 497                 {
 498                   gint n;
 499                   for (n = 0; n < num_fds; n++)
 500                     {
 501                       /* TODO: really want a append_steal() */
 502                       g_unix_fd_list_append (worker->read_fd_list, fds[n], NULL);
 503                       close (fds[n]);
 504                     }
 505                 }
 506               g_free (fds);
 507             }
 508           else if (G_IS_UNIX_CREDENTIALS_MESSAGE (control_message))
 509             {
 510               /* do nothing */
 511             }
 512 #endif
 513           else
 514             {
 515               if (error == NULL)
 516                 {
 517                   g_set_error (&error,
 518                                G_IO_ERROR,
 519                                G_IO_ERROR_FAILED,
 520                                "Unexpected ancillary message of type %s received from peer",
 521                                g_type_name (G_TYPE_FROM_INSTANCE (control_message)));
 522                   _g_dbus_worker_emit_disconnected (worker, TRUE, error);
 523                   g_error_free (error);
 524                   g_object_unref (control_message);
 525                   n++;
 526                   while (n < worker->read_num_ancillary_messages)
 527                     g_object_unref (worker->read_ancillary_messages[n++]);
 528                   g_free (worker->read_ancillary_messages);
 529                   goto out;
 530                 }
 531             }
 532           g_object_unref (control_message);
 533         }
 534       g_free (worker->read_ancillary_messages);
 535     }
 536
 537   if (bytes_read == -1)
 538     {
 539       _g_dbus_worker_emit_disconnected (worker, TRUE, error);
 540       g_error_free (error);
 541       goto out;
 542     }
 543
 544 #if 0
 545   g_debug ("read %d bytes (is_closed=%d blocking=%d condition=0x%02x) stream %p, %p",
 546            (gint) bytes_read,
 547            g_socket_is_closed (g_socket_connection_get_socket (G_SOCKET_CONNECTION (worker->stream))),
 548            g_socket_get_blocking (g_socket_connection_get_socket (G_SOCKET_CONNECTION (worker->stream))),
 549            g_socket_condition_check (g_socket_connection_get_socket (G_SOCKET_CONNECTION (worker->stream)),
 550                                      G_IO_IN | G_IO_OUT | G_IO_HUP),
 551            worker->stream,
 552            worker);
 553 #endif
 554
 555   /* TODO: hmm, hmm... */
 556   if (bytes_read == 0)
 557     {
 558       g_set_error (&error,
 559                    G_IO_ERROR,
 560                    G_IO_ERROR_FAILED,
 561                    "Underlying GIOStream returned 0 bytes on an async read");
 562       _g_dbus_worker_emit_disconnected (worker, TRUE, error);
 563       g_error_free (error);
 564       goto out;
 565     }
 566
 567   worker->read_buffer_cur_size += bytes_read;
 568   if (worker->read_buffer_bytes_wanted == worker->read_buffer_cur_size)
 569     {
 570       /* OK, got what we asked for! */
 571       if (worker->read_buffer_bytes_wanted == 16)
 572         {
 573           gssize message_len;
 574           /* OK, got the header - determine how many more bytes are needed */
 575           error = NULL;
 576           message_len = g_dbus_message_bytes_needed ((guchar *) worker->read_buffer,
 577                                                      16,
 578                                                      &error);
 579           if (message_len == -1)
 580             {
 581               g_warning ("_g_dbus_worker_do_read_cb: error determing bytes needed: %s", error->message);
 582               _g_dbus_worker_emit_disconnected (worker, FALSE, error);
 583               g_error_free (error);
 584               goto out;
 585             }
 586
 587           worker->read_buffer_bytes_wanted = message_len;
 588           _g_dbus_worker_do_read_unlocked (worker);
 589         }
 590       else
 591         {
 592           GDBusMessage *message;
 593           error = NULL;
 594
 595           /* TODO: use connection->priv->auth to decode the message */
 596
 597           message = g_dbus_message_new_from_blob ((guchar *) worker->read_buffer,
 598                                                   worker->read_buffer_cur_size,
 599                                                   worker->capabilities,
 600                                                   &error);
 601           if (message == NULL)
 602             {
 603               gchar *s;
 604               s = _g_dbus_hexdump (worker->read_buffer, worker->read_buffer_cur_size, 2);
 605               g_warning ("Error decoding D-Bus message of %" G_GSIZE_FORMAT " bytes\n"
 606                          "The error is: %s\n"
 607                          "The payload is as follows:\n"
 608                          "%s\n",
 609                          worker->read_buffer_cur_size,
 610                          error->message,
 611                          s);
 612               g_free (s);
 613               _g_dbus_worker_emit_disconnected (worker, FALSE, error);
 614               g_error_free (error);
 615               goto out;
 616             }
 617
 618 #ifdef G_OS_UNIX
 619           if (worker->read_fd_list != NULL)
 620             {
 621               g_dbus_message_set_unix_fd_list (message, worker->read_fd_list);
 622               worker->read_fd_list = NULL;
 623             }
 624 #endif
 625
 626           if (G_UNLIKELY (_g_dbus_debug_message ()))
 627             {
 628               gchar *s;
 629               g_print ("========================================================================\n"
 630                        "GDBus-debug:Message:\n"
 631                        "  <<<< RECEIVED D-Bus message (%" G_GSIZE_FORMAT " bytes)\n",
 632                        worker->read_buffer_cur_size);
 633               s = g_dbus_message_print (message, 2);
 634               g_print ("%s", s);
 635               g_free (s);
 636               s = _g_dbus_hexdump (worker->read_buffer, worker->read_buffer_cur_size, 2);
 637               g_print ("%s\n", s);
 638               g_free (s);
 639             }
 640
 641           /* yay, got a message, go deliver it */
 642           _g_dbus_worker_emit_message_received (worker, message);
 643           g_object_unref (message);
 644
 645           /* start reading another message! */
 646           worker->read_buffer_bytes_wanted = 0;
 647           worker->read_buffer_cur_size = 0;
 648           _g_dbus_worker_do_read_unlocked (worker);
 649         }
 650     }
 651   else
 652     {
 653       /* didn't get all the bytes we requested - so repeat the request... */
 654       _g_dbus_worker_do_read_unlocked (worker);
 655     }
 656
 657  out:
 658   g_mutex_unlock (worker->read_lock);
 659
 660   /* gives up the reference acquired when calling g_input_stream_read_async() */
 661   _g_dbus_worker_unref (worker);
 662 }
 663
 664 /* called in private thread shared by all GDBusConnection instances (with read-lock held) */
 665 static void
 666 _g_dbus_worker_do_read_unlocked (GDBusWorker *worker)
 667 {
 668   /* if bytes_wanted is zero, it means start reading a message */
 669   if (worker->read_buffer_bytes_wanted == 0)
 670     {
 671       worker->read_buffer_cur_size = 0;
 672       worker->read_buffer_bytes_wanted = 16;
 673     }
 674
 675   /* ensure we have a (big enough) buffer */
 676   if (worker->read_buffer == NULL || worker->read_buffer_bytes_wanted > worker->read_buffer_allocated_size)
 677     {
 678       /* TODO: 4096 is randomly chosen; might want a better chosen default minimum */
 679       worker->read_buffer_allocated_size = MAX (worker->read_buffer_bytes_wanted, 4096);
 680       worker->read_buffer = g_realloc (worker->read_buffer, worker->read_buffer_allocated_size);
 681     }
 682
 683   if (worker->socket == NULL)
 684     g_input_stream_read_async (g_io_stream_get_input_stream (worker->stream),
 685                                worker->read_buffer + worker->read_buffer_cur_size,
 686                                worker->read_buffer_bytes_wanted - worker->read_buffer_cur_size,
 687                                G_PRIORITY_DEFAULT,
 688                                worker->cancellable,
 689                                (GAsyncReadyCallback) _g_dbus_worker_do_read_cb,
 690                                _g_dbus_worker_ref (worker));
 691   else
 692     {
 693       worker->read_ancillary_messages = NULL;
 694       worker->read_num_ancillary_messages = 0;
 695       _g_socket_read_with_control_messages (worker->socket,
 696                                             worker->read_buffer + worker->read_buffer_cur_size,
 697                                             worker->read_buffer_bytes_wanted - worker->read_buffer_cur_size,
 698                                             &worker->read_ancillary_messages,
 699                                             &worker->read_num_ancillary_messages,
 700                                             G_PRIORITY_DEFAULT,
 701                                             worker->cancellable,
 702                                             (GAsyncReadyCallback) _g_dbus_worker_do_read_cb,
 703                                             _g_dbus_worker_ref (worker));
 704     }
 705 }
 706
 707 /* called in private thread shared by all GDBusConnection instances (without read-lock held) */
 708 static void
 709 _g_dbus_worker_do_read (GDBusWorker *worker)
 710 {
 711   g_mutex_lock (worker->read_lock);
 712   _g_dbus_worker_do_read_unlocked (worker);
 713   g_mutex_unlock (worker->read_lock);
 714 }
 715
 716 /* ---------------------------------------------------------------------------------------------------- */
 717
 718 struct _MessageToWriteData
 719 {
 720   GDBusMessage *message;
 721   gchar        *blob;
 722   gsize         blob_size;
 723 };
 724
 725 static void
 726 message_to_write_data_free (MessageToWriteData *data)
 727 {
 728   g_object_unref (data->message);
 729   g_free (data->blob);
 730   g_free (data);
 731 }
 732
 733 /* ---------------------------------------------------------------------------------------------------- */
 734
 735 /* called in private thread shared by all GDBusConnection instances (without write-lock held) */
 736 static gboolean
 737 write_message (GDBusWorker         *worker,
 738                MessageToWriteData  *data,
 739                GError             **error)
 740 {
 741   gboolean ret;
 742
 743   g_return_val_if_fail (data->blob_size > 16, FALSE);
 744
 745   ret = FALSE;
 746
 747   /* First, the initial 16 bytes - special case UNIX sockets here
 748    * since it may involve writing an ancillary message with file
 749    * descriptors
 750    */
 751 #ifdef G_OS_UNIX
 752   {
 753     GOutputVector vector;
 754     GSocketControlMessage *message;
 755     GUnixFDList *fd_list;
 756     gssize bytes_written;
 757
 758     fd_list = g_dbus_message_get_unix_fd_list (data->message);
 759
 760     message = NULL;
 761     if (fd_list != NULL)
 762       {
 763         if (!G_IS_UNIX_CONNECTION (worker->stream))
 764           {
 765             g_set_error (error,
 766                          G_IO_ERROR,
 767                          G_IO_ERROR_INVALID_ARGUMENT,
 768                          "Tried sending a file descriptor on unsupported stream of type %s",
 769                          g_type_name (G_TYPE_FROM_INSTANCE (worker->stream)));
 770             goto out;
 771           }
 772         else if (!(worker->capabilities & G_DBUS_CAPABILITY_FLAGS_UNIX_FD_PASSING))
 773           {
 774             g_set_error_literal (error,
 775                                  G_IO_ERROR,
 776                                  G_IO_ERROR_INVALID_ARGUMENT,
 777                                  "Tried sending a file descriptor but remote peer does not support this capability");
 778             goto out;
 779           }
 780         message = g_unix_fd_message_new_with_fd_list (fd_list);
 781       }
 782
 783     vector.buffer = data->blob;
 784     vector.size = 16;
 785
 786     bytes_written = g_socket_send_message (worker->socket,
 787                                            NULL, /* address */
 788                                            &vector,
 789                                            1,
 790                                            message != NULL ? &message : NULL,
 791                                            message != NULL ? 1 : 0,
 792                                            G_SOCKET_MSG_NONE,
 793                                            worker->cancellable,
 794                                            error);
 795     if (bytes_written == -1)
 796       {
 797         g_prefix_error (error, _("Error writing first 16 bytes of message to socket: "));
 798         if (message != NULL)
 799           g_object_unref (message);
 800         goto out;
 801       }
 802     if (message != NULL)
 803       g_object_unref (message);
 804
 805     if (bytes_written < 16)
 806       {
 807         /* TODO: I think this needs to be handled ... are we guaranteed that the ancillary
 808          * messages are sent?
 809          */
 810         g_assert_not_reached ();
 811       }
 812   }
 813 #else
 814   /* write the first 16 bytes (guaranteed to return an error if everything can't be written) */
 815   if (!g_output_stream_write_all (g_io_stream_get_output_stream (worker->stream),
 816                                   (const gchar *) data->blob,
 817                                   16,
 818                                   NULL, /* bytes_written */
 819                                   worker->cancellable, /* cancellable */
 820                                   error))
 821     goto out;
 822 #endif
 823
 824   /* Then write the rest of the message (guaranteed to return an error if everything can't be written) */
 825   if (!g_output_stream_write_all (g_io_stream_get_output_stream (worker->stream),
 826                                   (const gchar *) data->blob + 16,
 827                                   data->blob_size - 16,
 828                                   NULL, /* bytes_written */
 829                                   worker->cancellable, /* cancellable */
 830                                   error))
 831     goto out;
 832
 833   ret = TRUE;
 834
 835   if (G_UNLIKELY (_g_dbus_debug_message ()))
 836     {
 837       gchar *s;
 838       g_print ("========================================================================\n"
 839                "GDBus-debug:Message:\n"
 840                "  >>>> SENT D-Bus message (%" G_GSIZE_FORMAT " bytes)\n",
 841                data->blob_size);
 842       s = g_dbus_message_print (data->message, 2);
 843       g_print ("%s", s);
 844       g_free (s);
 845       s = _g_dbus_hexdump (data->blob, data->blob_size, 2);
 846       g_print ("%s\n", s);
 847       g_free (s);
 848     }
 849
 850  out:
 851   return ret;
 852 }
 853
 854 /* ---------------------------------------------------------------------------------------------------- */
 855
 856 /* called in private thread shared by all GDBusConnection instances (without write-lock held) */
 857 static gboolean
 858 write_message_in_idle_cb (gpointer user_data)
 859 {
 860   GDBusWorker *worker = user_data;
 861   gboolean more_writes_are_pending;
 862   MessageToWriteData *data;
 863   gboolean message_was_dropped;
 864   GError *error;
 865
 866   g_mutex_lock (worker->write_lock);
 867   data = g_queue_pop_head (worker->write_queue);
 868   g_assert (data != NULL);
 869   more_writes_are_pending = (g_queue_get_length (worker->write_queue) > 0);
 870   worker->write_is_pending = more_writes_are_pending;
 871   g_mutex_unlock (worker->write_lock);
 872
 873   /* Note that write_lock is only used for protecting the @write_queue
 874    * and @write_is_pending fields of the GDBusWorker struct ... which we
 875    * need to modify from arbitrary threads in _g_dbus_worker_send_message().
 876    *
 877    * Therefore, it's fine to drop it here when calling back into user
 878    * code and then writing the message out onto the GIOStream since this
 879    * function only runs on the worker thread.
 880    */
 881   message_was_dropped = _g_dbus_worker_emit_message_about_to_be_sent (worker, data->message);
 882   if (G_LIKELY (!message_was_dropped))
 883     {
 884       error = NULL;
 885       if (!write_message (worker,
 886                           data,
 887                           &error))
 888         {
 889           /* TODO: handle */
 890           _g_dbus_worker_emit_disconnected (worker, TRUE, error);
 891           g_error_free (error);
 892         }
 893     }
 894   message_to_write_data_free (data);
 895
 896   return more_writes_are_pending;
 897 }
 898
 899 /* ---------------------------------------------------------------------------------------------------- */
 900
 901 /* can be called from any thread - steals blob */
 902 void
 903 _g_dbus_worker_send_message (GDBusWorker    *worker,
 904                              GDBusMessage   *message,
 905                              gchar          *blob,
 906                              gsize           blob_len)
 907 {
 908   MessageToWriteData *data;
 909
 910   g_return_if_fail (G_IS_DBUS_MESSAGE (message));
 911   g_return_if_fail (blob != NULL);
 912   g_return_if_fail (blob_len > 16);
 913
 914   data = g_new0 (MessageToWriteData, 1);
 915   data->message = g_object_ref (message);
 916   data->blob = blob; /* steal! */
 917   data->blob_size = blob_len;
 918
 919   g_mutex_lock (worker->write_lock);
 920   g_queue_push_tail (worker->write_queue, data);
 921   if (!worker->write_is_pending)
 922     {
 923       GSource *idle_source;
 924
 925       worker->write_is_pending = TRUE;
 926
 927       idle_source = g_idle_source_new ();
 928       g_source_set_priority (idle_source, G_PRIORITY_DEFAULT);
 929       g_source_set_callback (idle_source,
 930                              write_message_in_idle_cb,
 931                              _g_dbus_worker_ref (worker),
 932                              (GDestroyNotify) _g_dbus_worker_unref);
 933       g_source_attach (idle_source, shared_thread_data->context);
 934       g_source_unref (idle_source);
 935     }
 936   g_mutex_unlock (worker->write_lock);
 937 }
 938
 939 /* ---------------------------------------------------------------------------------------------------- */
 940
 941 static void
 942 _g_dbus_worker_thread_begin_func (gpointer user_data)
 943 {
 944   GDBusWorker *worker = user_data;
 945
 946   worker->thread = g_thread_self ();
 947
 948   /* begin reading */
 949   _g_dbus_worker_do_read (worker);
 950 }
 951
 952 GDBusWorker *
 953 _g_dbus_worker_new (GIOStream                              *stream,
 954                     GDBusCapabilityFlags                    capabilities,
 955                     GDBusWorkerMessageReceivedCallback      message_received_callback,
 956                     GDBusWorkerMessageAboutToBeSentCallback message_about_to_be_sent_callback,
 957                     GDBusWorkerDisconnectedCallback         disconnected_callback,
 958                     gpointer                                user_data)
 959 {
 960   GDBusWorker *worker;
 961
 962   g_return_val_if_fail (G_IS_IO_STREAM (stream), NULL);
 963   g_return_val_if_fail (message_received_callback != NULL, NULL);
 964   g_return_val_if_fail (message_about_to_be_sent_callback != NULL, NULL);
 965   g_return_val_if_fail (disconnected_callback != NULL, NULL);
 966
 967   worker = g_new0 (GDBusWorker, 1);
 968   worker->ref_count = 1;
 969
 970   worker->read_lock = g_mutex_new ();
 971   worker->message_received_callback = message_received_callback;
 972   worker->message_about_to_be_sent_callback = message_about_to_be_sent_callback;
 973   worker->disconnected_callback = disconnected_callback;
 974   worker->user_data = user_data;
 975   worker->stream = g_object_ref (stream);
 976   worker->capabilities = capabilities;
 977   worker->cancellable = g_cancellable_new ();
 978
 979   worker->write_lock = g_mutex_new ();
 980   worker->write_queue = g_queue_new ();
 981
 982   if (G_IS_SOCKET_CONNECTION (worker->stream))
 983     worker->socket = g_socket_connection_get_socket (G_SOCKET_CONNECTION (worker->stream));
 984
 985   _g_dbus_shared_thread_ref (_g_dbus_worker_thread_begin_func, worker);
 986
 987   return worker;
 988 }
 989
 990 /* This can be called from any thread - frees worker - guarantees no callbacks
 991  * will ever be issued again
 992  */
 993 void
 994 _g_dbus_worker_stop (GDBusWorker *worker)
 995 {
 996   /* If we're called in the worker thread it means we are called from
 997    * a worker callback. This is fine, we just can't lock in that case since
 998    * we're already holding the lock...
 999    */
1000   if (g_thread_self () != worker->thread)
1001     g_mutex_lock (worker->read_lock);
1002   worker->stopped = TRUE;
1003   if (g_thread_self () != worker->thread)
1004     g_mutex_unlock (worker->read_lock);
1005
1006   g_cancellable_cancel (worker->cancellable);
1007   _g_dbus_worker_unref (worker);
1008 }
1009
1010 #define G_DBUS_DEBUG_AUTHENTICATION (1<<0)
1011 #define G_DBUS_DEBUG_MESSAGE        (1<<1)
1012 #define G_DBUS_DEBUG_ALL            0xffffffff
1013 static gint _gdbus_debug_flags = 0;
1014
1015 gboolean
1016 _g_dbus_debug_authentication (void)
1017 {
1018   _g_dbus_initialize ();
1019   return (_gdbus_debug_flags & G_DBUS_DEBUG_AUTHENTICATION) != 0;
1020 }
1021
1022 gboolean
1023 _g_dbus_debug_message (void)
1024 {
1025   _g_dbus_initialize ();
1026   return (_gdbus_debug_flags & G_DBUS_DEBUG_MESSAGE) != 0;
1027 }
1028
1029 /*
1030  * _g_dbus_initialize:
1031  *
1032  * Does various one-time init things such as
1033  *
1034  *  - registering the G_DBUS_ERROR error domain
1035  *  - parses the G_DBUS_DEBUG environment variable
1036  */
1037 void
1038 _g_dbus_initialize (void)
1039 {
1040   static volatile gsize initialized = 0;
1041
1042   if (g_once_init_enter (&initialized))
1043     {
1044       volatile GQuark g_dbus_error_domain;
1045       const gchar *debug;
1046
1047       g_dbus_error_domain = G_DBUS_ERROR;
1048
1049       debug = g_getenv ("G_DBUS_DEBUG");
1050       if (debug != NULL)
1051         {
1052           gchar **tokens;
1053           guint n;
1054           tokens = g_strsplit (debug, ",", 0);
1055           for (n = 0; tokens[n] != NULL; n++)
1056             {
1057               if (g_strcmp0 (tokens[n], "authentication") == 0)
1058                 _gdbus_debug_flags |= G_DBUS_DEBUG_AUTHENTICATION;
1059               else if (g_strcmp0 (tokens[n], "message") == 0)
1060                 _gdbus_debug_flags |= G_DBUS_DEBUG_MESSAGE;
1061               else if (g_strcmp0 (tokens[n], "all") == 0)
1062                 _gdbus_debug_flags |= G_DBUS_DEBUG_ALL;
1063             }
1064           g_strfreev (tokens);
1065         }
1066
1067       g_once_init_leave (&initialized, 1);
1068     }
1069 }
1070
1071 /* ---------------------------------------------------------------------------------------------------- */
1072
1073 GVariantType *
1074 _g_dbus_compute_complete_signature (GDBusArgInfo **args)
1075 {
1076   const GVariantType *arg_types[256];
1077   guint n;
1078
1079   if (args)
1080     for (n = 0; args[n] != NULL; n++)
1081       {
1082         /* DBus places a hard limit of 255 on signature length.
1083          * therefore number of args must be less than 256.
1084          */
1085         g_assert (n < 256);
1086
1087         arg_types[n] = G_VARIANT_TYPE (args[n]->signature);
1088
1089         if G_UNLIKELY (arg_types[n] == NULL)
1090           return NULL;
1091       }
1092   else
1093     n = 0;
1094
1095   return g_variant_type_new_tuple (arg_types, n);
1096 }
1097
1098 /* ---------------------------------------------------------------------------------------------------- */
1099
1100 #ifdef G_OS_WIN32
1101
1102 extern BOOL WINAPI ConvertSidToStringSidA (PSID Sid, LPSTR *StringSid);
1103
1104 gchar *
1105 _g_dbus_win32_get_user_sid (void)
1106 {
1107   HANDLE h;
1108   TOKEN_USER *user;
1109   DWORD token_information_len;
1110   PSID psid;
1111   gchar *sid;
1112   gchar *ret;
1113
1114   ret = NULL;
1115   user = NULL;
1116   h = INVALID_HANDLE_VALUE;
1117
1118   if (!OpenProcessToken (GetCurrentProcess (), TOKEN_QUERY, &h))
1119     {
1120       g_warning ("OpenProcessToken failed with error code %d", (gint) GetLastError ());
1121       goto out;
1122     }
1123
1124   /* Get length of buffer */
1125   token_information_len = 0;
1126   if (!GetTokenInformation (h, TokenUser, NULL, 0, &token_information_len))
1127     {
1128       if (GetLastError () != ERROR_INSUFFICIENT_BUFFER)
1129         {
1130           g_warning ("GetTokenInformation() failed with error code %d", (gint) GetLastError ());
1131           goto out;
1132         }
1133     }
1134   user = g_malloc (token_information_len);
1135   if (!GetTokenInformation (h, TokenUser, user, token_information_len, &token_information_len))
1136     {
1137       g_warning ("GetTokenInformation() failed with error code %d", (gint) GetLastError ());
1138       goto out;
1139     }
1140
1141   psid = user->User.Sid;
1142   if (!IsValidSid (psid))
1143     {
1144       g_warning ("Invalid SID");
1145       goto out;
1146     }
1147
1148   if (!ConvertSidToStringSidA (psid, &sid))
1149     {
1150       g_warning ("Invalid SID");
1151       goto out;
1152     }
1153
1154   ret = g_strdup (sid);
1155   LocalFree (sid);
1156
1157 out:
1158   g_free (user);
1159   if (h != INVALID_HANDLE_VALUE)
1160     CloseHandle (h);
1161   return ret;
1162 }
1163 #endif
1164
1165 /* ---------------------------------------------------------------------------------------------------- */
1166
1167 #define __G_DBUS_PRIVATE_C__
1168 #include "gioaliasdef.c"