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 "gmemoryinputstream.h"
  41 #include "giostream.h"
  42 #include "gsocketcontrolmessage.h"
  43 #include "gsocketconnection.h"
  44 #include "gsocketoutputstream.h"
  45
  46 #ifdef G_OS_UNIX
  47 #include "gunixfdmessage.h"
  48 #include "gunixconnection.h"
  49 #include "gunixcredentialsmessage.h"
  50 #endif
  51
  52 #ifdef G_OS_WIN32
  53 #include <windows.h>
  54 #endif
  55
  56 #include "glibintl.h"
  57
  58 /* ---------------------------------------------------------------------------------------------------- */
  59
  60 gchar *
  61 _g_dbus_hexdump (const gchar *data, gsize len, guint indent)
  62 {
  63  guint n, m;
  64  GString *ret;
  65
  66  ret = g_string_new (NULL);
  67
  68  for (n = 0; n < len; n += 16)
  69    {
  70      g_string_append_printf (ret, "%*s%04x: ", indent, "", n);
  71
  72      for (m = n; m < n + 16; m++)
  73        {
  74          if (m > n && (m%4) == 0)
  75            g_string_append_c (ret, ' ');
  76          if (m < len)
  77            g_string_append_printf (ret, "%02x ", (guchar) data[m]);
  78          else
  79            g_string_append (ret, "   ");
  80        }
  81
  82      g_string_append (ret, "   ");
  83
  84      for (m = n; m < len && m < n + 16; m++)
  85        g_string_append_c (ret, g_ascii_isprint (data[m]) ? data[m] : '.');
  86
  87      g_string_append_c (ret, '\n');
  88    }
  89
  90  return g_string_free (ret, FALSE);
  91 }
  92
  93 /* ---------------------------------------------------------------------------------------------------- */
  94
  95 /* Unfortunately ancillary messages are discarded when reading from a
  96  * socket using the GSocketInputStream abstraction. So we provide a
  97  * very GInputStream-ish API that uses GSocket in this case (very
  98  * similar to GSocketInputStream).
  99  */
 100
 101 typedef struct
 102 {
 103   GSocket *socket;
 104   GCancellable *cancellable;
 105
 106   void *buffer;
 107   gsize count;
 108
 109   GSocketControlMessage ***messages;
 110   gint *num_messages;
 111
 112   GSimpleAsyncResult *simple;
 113
 114   gboolean from_mainloop;
 115 } ReadWithControlData;
 116
 117 static void
 118 read_with_control_data_free (ReadWithControlData *data)
 119 {
 120   g_object_unref (data->socket);
 121   if (data->cancellable != NULL)
 122     g_object_unref (data->cancellable);
 123   g_object_unref (data->simple);
 124   g_free (data);
 125 }
 126
 127 static gboolean
 128 _g_socket_read_with_control_messages_ready (GSocket      *socket,
 129                                             GIOCondition  condition,
 130                                             gpointer      user_data)
 131 {
 132   ReadWithControlData *data = user_data;
 133   GError *error;
 134   gssize result;
 135   GInputVector vector;
 136
 137   error = NULL;
 138   vector.buffer = data->buffer;
 139   vector.size = data->count;
 140   result = g_socket_receive_message (data->socket,
 141                                      NULL, /* address */
 142                                      &vector,
 143                                      1,
 144                                      data->messages,
 145                                      data->num_messages,
 146                                      NULL,
 147                                      data->cancellable,
 148                                      &error);
 149   if (result >= 0)
 150     {
 151       g_simple_async_result_set_op_res_gssize (data->simple, result);
 152     }
 153   else
 154     {
 155       g_assert (error != NULL);
 156       g_simple_async_result_set_from_error (data->simple, error);
 157       g_error_free (error);
 158     }
 159
 160   if (data->from_mainloop)
 161     g_simple_async_result_complete (data->simple);
 162   else
 163     g_simple_async_result_complete_in_idle (data->simple);
 164
 165   return FALSE;
 166 }
 167
 168 static void
 169 _g_socket_read_with_control_messages (GSocket                 *socket,
 170                                       void                    *buffer,
 171                                       gsize                    count,
 172                                       GSocketControlMessage ***messages,
 173                                       gint                    *num_messages,
 174                                       gint                     io_priority,
 175                                       GCancellable            *cancellable,
 176                                       GAsyncReadyCallback      callback,
 177                                       gpointer                 user_data)
 178 {
 179   ReadWithControlData *data;
 180
 181   data = g_new0 (ReadWithControlData, 1);
 182   data->socket = g_object_ref (socket);
 183   data->cancellable = cancellable != NULL ? g_object_ref (cancellable) : NULL;
 184   data->buffer = buffer;
 185   data->count = count;
 186   data->messages = messages;
 187   data->num_messages = num_messages;
 188
 189   data->simple = g_simple_async_result_new (G_OBJECT (socket),
 190                                             callback,
 191                                             user_data,
 192                                             _g_socket_read_with_control_messages);
 193
 194   if (!g_socket_condition_check (socket, G_IO_IN))
 195     {
 196       GSource *source;
 197       data->from_mainloop = TRUE;
 198       source = g_socket_create_source (data->socket,
 199                                        G_IO_IN | G_IO_HUP | G_IO_ERR,
 200                                        cancellable);
 201       g_source_set_callback (source,
 202                              (GSourceFunc) _g_socket_read_with_control_messages_ready,
 203                              data,
 204                              (GDestroyNotify) read_with_control_data_free);
 205       g_source_attach (source, g_main_context_get_thread_default ());
 206       g_source_unref (source);
 207     }
 208   else
 209     {
 210       _g_socket_read_with_control_messages_ready (data->socket, G_IO_IN, data);
 211       read_with_control_data_free (data);
 212     }
 213 }
 214
 215 static gssize
 216 _g_socket_read_with_control_messages_finish (GSocket       *socket,
 217                                              GAsyncResult  *result,
 218                                              GError       **error)
 219 {
 220   GSimpleAsyncResult *simple = G_SIMPLE_ASYNC_RESULT (result);
 221
 222   g_return_val_if_fail (G_IS_SOCKET (socket), -1);
 223   g_warn_if_fail (g_simple_async_result_get_source_tag (simple) == _g_socket_read_with_control_messages);
 224
 225   if (g_simple_async_result_propagate_error (simple, error))
 226       return -1;
 227   else
 228     return g_simple_async_result_get_op_res_gssize (simple);
 229 }
 230
 231 /* ---------------------------------------------------------------------------------------------------- */
 232
 233 /* Work-around for https://bugzilla.gnome.org/show_bug.cgi?id=627724 */
 234
 235 static GPtrArray *ensured_classes = NULL;
 236
 237 static void
 238 ensure_type (GType gtype)
 239 {
 240   g_ptr_array_add (ensured_classes, g_type_class_ref (gtype));
 241 }
 242
 243 static void
 244 released_required_types (void)
 245 {
 246   g_ptr_array_foreach (ensured_classes, (GFunc) g_type_class_unref, NULL);
 247   g_ptr_array_unref (ensured_classes);
 248   ensured_classes = NULL;
 249 }
 250
 251 static void
 252 ensure_required_types (void)
 253 {
 254   g_assert (ensured_classes == NULL);
 255   ensured_classes = g_ptr_array_new ();
 256   ensure_type (G_TYPE_SIMPLE_ASYNC_RESULT);
 257   ensure_type (G_TYPE_MEMORY_INPUT_STREAM);
 258 }
 259 /* ---------------------------------------------------------------------------------------------------- */
 260
 261 G_LOCK_DEFINE_STATIC (shared_thread_lock);
 262
 263 typedef struct
 264 {
 265   gint num_users;
 266   GThread *thread;
 267   GMainContext *context;
 268   GMainLoop *loop;
 269 } SharedThreadData;
 270
 271 static SharedThreadData *shared_thread_data = NULL;
 272
 273 static gpointer
 274 gdbus_shared_thread_func (gpointer data)
 275 {
 276   g_main_context_push_thread_default (shared_thread_data->context);
 277   g_main_loop_run (shared_thread_data->loop);
 278   g_main_context_pop_thread_default (shared_thread_data->context);
 279   return NULL;
 280 }
 281
 282 typedef void (*GDBusSharedThreadFunc) (gpointer user_data);
 283
 284 typedef struct
 285 {
 286   GDBusSharedThreadFunc func;
 287   gpointer              user_data;
 288   gboolean              done;
 289 } CallerData;
 290
 291 static gboolean
 292 invoke_caller (gpointer user_data)
 293 {
 294   CallerData *data = user_data;
 295   data->func (data->user_data);
 296   data->done = TRUE;
 297   return FALSE;
 298 }
 299
 300 /* ---------------------------------------------------------------------------------------------------- */
 301
 302 static void
 303 _g_dbus_shared_thread_ref (GDBusSharedThreadFunc func,
 304                            gpointer              user_data)
 305 {
 306   GError *error;
 307   GSource *idle_source;
 308   CallerData *data;
 309   gboolean release_types;
 310
 311   G_LOCK (shared_thread_lock);
 312
 313   release_types = FALSE;
 314
 315   if (shared_thread_data != NULL)
 316     {
 317       shared_thread_data->num_users += 1;
 318       goto have_thread;
 319     }
 320
 321   shared_thread_data = g_new0 (SharedThreadData, 1);
 322   shared_thread_data->num_users = 1;
 323
 324   /* Work-around for https://bugzilla.gnome.org/show_bug.cgi?id=627724 */
 325   ensure_required_types ();
 326   release_types = TRUE;
 327
 328   error = NULL;
 329   shared_thread_data->context = g_main_context_new ();
 330   shared_thread_data->loop = g_main_loop_new (shared_thread_data->context, FALSE);
 331   shared_thread_data->thread = g_thread_create (gdbus_shared_thread_func,
 332                                                 NULL,
 333                                                 TRUE,
 334                                                 &error);
 335   g_assert_no_error (error);
 336
 337  have_thread:
 338
 339   data = g_new0 (CallerData, 1);
 340   data->func = func;
 341   data->user_data = user_data;
 342   data->done = FALSE;
 343
 344   idle_source = g_idle_source_new ();
 345   g_source_set_priority (idle_source, G_PRIORITY_DEFAULT);
 346   g_source_set_callback (idle_source,
 347                          invoke_caller,
 348                          data,
 349                          NULL);
 350   g_source_attach (idle_source, shared_thread_data->context);
 351   g_source_unref (idle_source);
 352
 353   /* wait for the user code to run.. hmm.. probably use a condition variable instead */
 354   while (!data->done)
 355     g_thread_yield ();
 356
 357   if (release_types)
 358     released_required_types ();
 359
 360   g_free (data);
 361
 362   G_UNLOCK (shared_thread_lock);
 363 }
 364
 365 static void
 366 _g_dbus_shared_thread_unref (void)
 367 {
 368   /* TODO: actually destroy the shared thread here */
 369 #if 0
 370   G_LOCK (shared_thread_lock);
 371   g_assert (shared_thread_data != NULL);
 372   shared_thread_data->num_users -= 1;
 373   if (shared_thread_data->num_users == 0)
 374     {
 375       g_main_loop_quit (shared_thread_data->loop);
 376       //g_thread_join (shared_thread_data->thread);
 377       g_main_loop_unref (shared_thread_data->loop);
 378       g_main_context_unref (shared_thread_data->context);
 379       g_free (shared_thread_data);
 380       shared_thread_data = NULL;
 381       G_UNLOCK (shared_thread_lock);
 382     }
 383   else
 384     {
 385       G_UNLOCK (shared_thread_lock);
 386     }
 387 #endif
 388 }
 389
 390 /* ---------------------------------------------------------------------------------------------------- */
 391
 392 struct GDBusWorker
 393 {
 394   volatile gint                       ref_count;
 395
 396   gboolean                            stopped;
 397
 398   /* TODO: frozen (e.g. G_DBUS_CONNECTION_FLAGS_DELAY_MESSAGE_PROCESSING) currently
 399    * only affects messages received from the other peer (since GDBusServer is the
 400    * only user) - we might want it to affect messages sent to the other peer too?
 401    */
 402   gboolean                            frozen;
 403   GQueue                             *received_messages_while_frozen;
 404
 405   GIOStream                          *stream;
 406   GDBusCapabilityFlags                capabilities;
 407   GCancellable                       *cancellable;
 408   GDBusWorkerMessageReceivedCallback  message_received_callback;
 409   GDBusWorkerMessageAboutToBeSentCallback message_about_to_be_sent_callback;
 410   GDBusWorkerDisconnectedCallback     disconnected_callback;
 411   gpointer                            user_data;
 412
 413   GThread                            *thread;
 414
 415   /* if not NULL, stream is GSocketConnection */
 416   GSocket *socket;
 417
 418   /* used for reading */
 419   GMutex                             *read_lock;
 420   gchar                              *read_buffer;
 421   gsize                               read_buffer_allocated_size;
 422   gsize                               read_buffer_cur_size;
 423   gsize                               read_buffer_bytes_wanted;
 424   GUnixFDList                        *read_fd_list;
 425   GSocketControlMessage             **read_ancillary_messages;
 426   gint                                read_num_ancillary_messages;
 427
 428   /* used for writing */
 429   GMutex                             *write_lock;
 430   GQueue                             *write_queue;
 431   gint                                num_writes_pending;
 432   guint64                             write_num_messages_written;
 433   GList                              *write_pending_flushes;
 434 };
 435
 436 /* ---------------------------------------------------------------------------------------------------- */
 437
 438 typedef struct
 439 {
 440   GMutex *mutex;
 441   GCond *cond;
 442   guint64 number_to_wait_for;
 443   GError *error;
 444 } FlushData;
 445
 446 struct _MessageToWriteData ;
 447 typedef struct _MessageToWriteData MessageToWriteData;
 448
 449 static void message_to_write_data_free (MessageToWriteData *data);
 450
 451 static void read_message_print_transport_debug (gssize bytes_read,
 452                                                 GDBusWorker *worker);
 453
 454 static void write_message_print_transport_debug (gssize bytes_written,
 455                                                  MessageToWriteData *data);
 456
 457 /* ---------------------------------------------------------------------------------------------------- */
 458
 459 static GDBusWorker *
 460 _g_dbus_worker_ref (GDBusWorker *worker)
 461 {
 462   g_atomic_int_inc (&worker->ref_count);
 463   return worker;
 464 }
 465
 466 static void
 467 _g_dbus_worker_unref (GDBusWorker *worker)
 468 {
 469   if (g_atomic_int_dec_and_test (&worker->ref_count))
 470     {
 471       g_assert (worker->write_pending_flushes == NULL);
 472
 473       _g_dbus_shared_thread_unref ();
 474
 475       g_object_unref (worker->stream);
 476
 477       g_mutex_free (worker->read_lock);
 478       g_object_unref (worker->cancellable);
 479       if (worker->read_fd_list != NULL)
 480         g_object_unref (worker->read_fd_list);
 481
 482       g_queue_foreach (worker->received_messages_while_frozen, (GFunc) g_object_unref, NULL);
 483       g_queue_free (worker->received_messages_while_frozen);
 484
 485       g_mutex_free (worker->write_lock);
 486       g_queue_foreach (worker->write_queue, (GFunc) message_to_write_data_free, NULL);
 487       g_queue_free (worker->write_queue);
 488
 489       g_free (worker->read_buffer);
 490
 491       g_free (worker);
 492     }
 493 }
 494
 495 static void
 496 _g_dbus_worker_emit_disconnected (GDBusWorker  *worker,
 497                                   gboolean      remote_peer_vanished,
 498                                   GError       *error)
 499 {
 500   if (!worker->stopped)
 501     worker->disconnected_callback (worker, remote_peer_vanished, error, worker->user_data);
 502 }
 503
 504 static void
 505 _g_dbus_worker_emit_message_received (GDBusWorker  *worker,
 506                                       GDBusMessage *message)
 507 {
 508   if (!worker->stopped)
 509     worker->message_received_callback (worker, message, worker->user_data);
 510 }
 511
 512 static GDBusMessage *
 513 _g_dbus_worker_emit_message_about_to_be_sent (GDBusWorker  *worker,
 514                                               GDBusMessage *message)
 515 {
 516   GDBusMessage *ret;
 517   if (!worker->stopped)
 518     ret = worker->message_about_to_be_sent_callback (worker, message, worker->user_data);
 519   else
 520     ret = message;
 521   return ret;
 522 }
 523
 524 /* can only be called from private thread with read-lock held - takes ownership of @message */
 525 static void
 526 _g_dbus_worker_queue_or_deliver_received_message (GDBusWorker  *worker,
 527                                                   GDBusMessage *message)
 528 {
 529   if (worker->frozen || g_queue_get_length (worker->received_messages_while_frozen) > 0)
 530     {
 531       /* queue up */
 532       g_queue_push_tail (worker->received_messages_while_frozen, message);
 533     }
 534   else
 535     {
 536       /* not frozen, nor anything in queue */
 537       _g_dbus_worker_emit_message_received (worker, message);
 538       g_object_unref (message);
 539     }
 540 }
 541
 542 /* called in private thread shared by all GDBusConnection instances (without read-lock held) */
 543 static gboolean
 544 unfreeze_in_idle_cb (gpointer user_data)
 545 {
 546   GDBusWorker *worker = user_data;
 547   GDBusMessage *message;
 548
 549   g_mutex_lock (worker->read_lock);
 550   if (worker->frozen)
 551     {
 552       while ((message = g_queue_pop_head (worker->received_messages_while_frozen)) != NULL)
 553         {
 554           _g_dbus_worker_emit_message_received (worker, message);
 555           g_object_unref (message);
 556         }
 557       worker->frozen = FALSE;
 558     }
 559   else
 560     {
 561       g_assert (g_queue_get_length (worker->received_messages_while_frozen) == 0);
 562     }
 563   g_mutex_unlock (worker->read_lock);
 564   return FALSE;
 565 }
 566
 567 /* can be called from any thread */
 568 void
 569 _g_dbus_worker_unfreeze (GDBusWorker *worker)
 570 {
 571   GSource *idle_source;
 572   idle_source = g_idle_source_new ();
 573   g_source_set_priority (idle_source, G_PRIORITY_DEFAULT);
 574   g_source_set_callback (idle_source,
 575                          unfreeze_in_idle_cb,
 576                          _g_dbus_worker_ref (worker),
 577                          (GDestroyNotify) _g_dbus_worker_unref);
 578   g_source_attach (idle_source, shared_thread_data->context);
 579   g_source_unref (idle_source);
 580 }
 581
 582 /* ---------------------------------------------------------------------------------------------------- */
 583
 584 static void _g_dbus_worker_do_read_unlocked (GDBusWorker *worker);
 585
 586 /* called in private thread shared by all GDBusConnection instances (without read-lock held) */
 587 static void
 588 _g_dbus_worker_do_read_cb (GInputStream  *input_stream,
 589                            GAsyncResult  *res,
 590                            gpointer       user_data)
 591 {
 592   GDBusWorker *worker = user_data;
 593   GError *error;
 594   gssize bytes_read;
 595
 596   g_mutex_lock (worker->read_lock);
 597
 598   /* If already stopped, don't even process the reply */
 599   if (worker->stopped)
 600     goto out;
 601
 602   error = NULL;
 603   if (worker->socket == NULL)
 604     bytes_read = g_input_stream_read_finish (g_io_stream_get_input_stream (worker->stream),
 605                                              res,
 606                                              &error);
 607   else
 608     bytes_read = _g_socket_read_with_control_messages_finish (worker->socket,
 609                                                               res,
 610                                                               &error);
 611   if (worker->read_num_ancillary_messages > 0)
 612     {
 613       gint n;
 614       for (n = 0; n < worker->read_num_ancillary_messages; n++)
 615         {
 616           GSocketControlMessage *control_message = G_SOCKET_CONTROL_MESSAGE (worker->read_ancillary_messages[n]);
 617
 618           if (FALSE)
 619             {
 620             }
 621 #ifdef G_OS_UNIX
 622           else if (G_IS_UNIX_FD_MESSAGE (control_message))
 623             {
 624               GUnixFDMessage *fd_message;
 625               gint *fds;
 626               gint num_fds;
 627
 628               fd_message = G_UNIX_FD_MESSAGE (control_message);
 629               fds = g_unix_fd_message_steal_fds (fd_message, &num_fds);
 630               if (worker->read_fd_list == NULL)
 631                 {
 632                   worker->read_fd_list = g_unix_fd_list_new_from_array (fds, num_fds);
 633                 }
 634               else
 635                 {
 636                   gint n;
 637                   for (n = 0; n < num_fds; n++)
 638                     {
 639                       /* TODO: really want a append_steal() */
 640                       g_unix_fd_list_append (worker->read_fd_list, fds[n], NULL);
 641                       close (fds[n]);
 642                     }
 643                 }
 644               g_free (fds);
 645             }
 646           else if (G_IS_UNIX_CREDENTIALS_MESSAGE (control_message))
 647             {
 648               /* do nothing */
 649             }
 650 #endif
 651           else
 652             {
 653               if (error == NULL)
 654                 {
 655                   g_set_error (&error,
 656                                G_IO_ERROR,
 657                                G_IO_ERROR_FAILED,
 658                                "Unexpected ancillary message of type %s received from peer",
 659                                g_type_name (G_TYPE_FROM_INSTANCE (control_message)));
 660                   _g_dbus_worker_emit_disconnected (worker, TRUE, error);
 661                   g_error_free (error);
 662                   g_object_unref (control_message);
 663                   n++;
 664                   while (n < worker->read_num_ancillary_messages)
 665                     g_object_unref (worker->read_ancillary_messages[n++]);
 666                   g_free (worker->read_ancillary_messages);
 667                   goto out;
 668                 }
 669             }
 670           g_object_unref (control_message);
 671         }
 672       g_free (worker->read_ancillary_messages);
 673     }
 674
 675   if (bytes_read == -1)
 676     {
 677       _g_dbus_worker_emit_disconnected (worker, TRUE, error);
 678       g_error_free (error);
 679       goto out;
 680     }
 681
 682 #if 0
 683   g_debug ("read %d bytes (is_closed=%d blocking=%d condition=0x%02x) stream %p, %p",
 684            (gint) bytes_read,
 685            g_socket_is_closed (g_socket_connection_get_socket (G_SOCKET_CONNECTION (worker->stream))),
 686            g_socket_get_blocking (g_socket_connection_get_socket (G_SOCKET_CONNECTION (worker->stream))),
 687            g_socket_condition_check (g_socket_connection_get_socket (G_SOCKET_CONNECTION (worker->stream)),
 688                                      G_IO_IN | G_IO_OUT | G_IO_HUP),
 689            worker->stream,
 690            worker);
 691 #endif
 692
 693   /* TODO: hmm, hmm... */
 694   if (bytes_read == 0)
 695     {
 696       g_set_error (&error,
 697                    G_IO_ERROR,
 698                    G_IO_ERROR_FAILED,
 699                    "Underlying GIOStream returned 0 bytes on an async read");
 700       _g_dbus_worker_emit_disconnected (worker, TRUE, error);
 701       g_error_free (error);
 702       goto out;
 703     }
 704
 705   read_message_print_transport_debug (bytes_read, worker);
 706
 707   worker->read_buffer_cur_size += bytes_read;
 708   if (worker->read_buffer_bytes_wanted == worker->read_buffer_cur_size)
 709     {
 710       /* OK, got what we asked for! */
 711       if (worker->read_buffer_bytes_wanted == 16)
 712         {
 713           gssize message_len;
 714           /* OK, got the header - determine how many more bytes are needed */
 715           error = NULL;
 716           message_len = g_dbus_message_bytes_needed ((guchar *) worker->read_buffer,
 717                                                      16,
 718                                                      &error);
 719           if (message_len == -1)
 720             {
 721               g_warning ("_g_dbus_worker_do_read_cb: error determing bytes needed: %s", error->message);
 722               _g_dbus_worker_emit_disconnected (worker, FALSE, error);
 723               g_error_free (error);
 724               goto out;
 725             }
 726
 727           worker->read_buffer_bytes_wanted = message_len;
 728           _g_dbus_worker_do_read_unlocked (worker);
 729         }
 730       else
 731         {
 732           GDBusMessage *message;
 733           error = NULL;
 734
 735           /* TODO: use connection->priv->auth to decode the message */
 736
 737           message = g_dbus_message_new_from_blob ((guchar *) worker->read_buffer,
 738                                                   worker->read_buffer_cur_size,
 739                                                   worker->capabilities,
 740                                                   &error);
 741           if (message == NULL)
 742             {
 743               gchar *s;
 744               s = _g_dbus_hexdump (worker->read_buffer, worker->read_buffer_cur_size, 2);
 745               g_warning ("Error decoding D-Bus message of %" G_GSIZE_FORMAT " bytes\n"
 746                          "The error is: %s\n"
 747                          "The payload is as follows:\n"
 748                          "%s\n",
 749                          worker->read_buffer_cur_size,
 750                          error->message,
 751                          s);
 752               g_free (s);
 753               _g_dbus_worker_emit_disconnected (worker, FALSE, error);
 754               g_error_free (error);
 755               goto out;
 756             }
 757
 758 #ifdef G_OS_UNIX
 759           if (worker->read_fd_list != NULL)
 760             {
 761               g_dbus_message_set_unix_fd_list (message, worker->read_fd_list);
 762               g_object_unref (worker->read_fd_list);
 763               worker->read_fd_list = NULL;
 764             }
 765 #endif
 766
 767           if (G_UNLIKELY (_g_dbus_debug_message ()))
 768             {
 769               gchar *s;
 770               _g_dbus_debug_print_lock ();
 771               g_print ("========================================================================\n"
 772                        "GDBus-debug:Message:\n"
 773                        "  <<<< RECEIVED D-Bus message (%" G_GSIZE_FORMAT " bytes)\n",
 774                        worker->read_buffer_cur_size);
 775               s = g_dbus_message_print (message, 2);
 776               g_print ("%s", s);
 777               g_free (s);
 778               if (G_UNLIKELY (_g_dbus_debug_payload ()))
 779                 {
 780                   s = _g_dbus_hexdump (worker->read_buffer, worker->read_buffer_cur_size, 2);
 781                   g_print ("%s\n", s);
 782                   g_free (s);
 783                 }
 784               _g_dbus_debug_print_unlock ();
 785             }
 786
 787           /* yay, got a message, go deliver it */
 788           _g_dbus_worker_queue_or_deliver_received_message (worker, message);
 789
 790           /* start reading another message! */
 791           worker->read_buffer_bytes_wanted = 0;
 792           worker->read_buffer_cur_size = 0;
 793           _g_dbus_worker_do_read_unlocked (worker);
 794         }
 795     }
 796   else
 797     {
 798       /* didn't get all the bytes we requested - so repeat the request... */
 799       _g_dbus_worker_do_read_unlocked (worker);
 800     }
 801
 802  out:
 803   g_mutex_unlock (worker->read_lock);
 804
 805   /* gives up the reference acquired when calling g_input_stream_read_async() */
 806   _g_dbus_worker_unref (worker);
 807 }
 808
 809 /* called in private thread shared by all GDBusConnection instances (with read-lock held) */
 810 static void
 811 _g_dbus_worker_do_read_unlocked (GDBusWorker *worker)
 812 {
 813   /* if bytes_wanted is zero, it means start reading a message */
 814   if (worker->read_buffer_bytes_wanted == 0)
 815     {
 816       worker->read_buffer_cur_size = 0;
 817       worker->read_buffer_bytes_wanted = 16;
 818     }
 819
 820   /* ensure we have a (big enough) buffer */
 821   if (worker->read_buffer == NULL || worker->read_buffer_bytes_wanted > worker->read_buffer_allocated_size)
 822     {
 823       /* TODO: 4096 is randomly chosen; might want a better chosen default minimum */
 824       worker->read_buffer_allocated_size = MAX (worker->read_buffer_bytes_wanted, 4096);
 825       worker->read_buffer = g_realloc (worker->read_buffer, worker->read_buffer_allocated_size);
 826     }
 827
 828   if (worker->socket == NULL)
 829     g_input_stream_read_async (g_io_stream_get_input_stream (worker->stream),
 830                                worker->read_buffer + worker->read_buffer_cur_size,
 831                                worker->read_buffer_bytes_wanted - worker->read_buffer_cur_size,
 832                                G_PRIORITY_DEFAULT,
 833                                worker->cancellable,
 834                                (GAsyncReadyCallback) _g_dbus_worker_do_read_cb,
 835                                _g_dbus_worker_ref (worker));
 836   else
 837     {
 838       worker->read_ancillary_messages = NULL;
 839       worker->read_num_ancillary_messages = 0;
 840       _g_socket_read_with_control_messages (worker->socket,
 841                                             worker->read_buffer + worker->read_buffer_cur_size,
 842                                             worker->read_buffer_bytes_wanted - worker->read_buffer_cur_size,
 843                                             &worker->read_ancillary_messages,
 844                                             &worker->read_num_ancillary_messages,
 845                                             G_PRIORITY_DEFAULT,
 846                                             worker->cancellable,
 847                                             (GAsyncReadyCallback) _g_dbus_worker_do_read_cb,
 848                                             _g_dbus_worker_ref (worker));
 849     }
 850 }
 851
 852 /* called in private thread shared by all GDBusConnection instances (without read-lock held) */
 853 static void
 854 _g_dbus_worker_do_read (GDBusWorker *worker)
 855 {
 856   g_mutex_lock (worker->read_lock);
 857   _g_dbus_worker_do_read_unlocked (worker);
 858   g_mutex_unlock (worker->read_lock);
 859 }
 860
 861 /* ---------------------------------------------------------------------------------------------------- */
 862
 863 struct _MessageToWriteData
 864 {
 865   GDBusWorker  *worker;
 866   GDBusMessage *message;
 867   gchar        *blob;
 868   gsize         blob_size;
 869
 870   gsize               total_written;
 871   GSimpleAsyncResult *simple;
 872
 873 };
 874
 875 static void
 876 message_to_write_data_free (MessageToWriteData *data)
 877 {
 878   _g_dbus_worker_unref (data->worker);
 879   g_object_unref (data->message);
 880   g_free (data->blob);
 881   g_free (data);
 882 }
 883
 884 /* ---------------------------------------------------------------------------------------------------- */
 885
 886 static void write_message_continue_writing (MessageToWriteData *data);
 887
 888 /* called in private thread shared by all GDBusConnection instances (without write-lock held) */
 889 static void
 890 write_message_async_cb (GObject      *source_object,
 891                         GAsyncResult *res,
 892                         gpointer      user_data)
 893 {
 894   MessageToWriteData *data = user_data;
 895   GSimpleAsyncResult *simple;
 896   gssize bytes_written;
 897   GError *error;
 898
 899   /* Note: we can't access data->simple after calling g_async_result_complete () because the
 900    * callback can free @data and we're not completing in idle. So use a copy of the pointer.
 901    */
 902   simple = data->simple;
 903
 904   error = NULL;
 905   bytes_written = g_output_stream_write_finish (G_OUTPUT_STREAM (source_object),
 906                                                 res,
 907                                                 &error);
 908   if (bytes_written == -1)
 909     {
 910       g_simple_async_result_set_from_error (simple, error);
 911       g_error_free (error);
 912       g_simple_async_result_complete (simple);
 913       g_object_unref (simple);
 914       goto out;
 915     }
 916   g_assert (bytes_written > 0); /* zero is never returned */
 917
 918   write_message_print_transport_debug (bytes_written, data);
 919
 920   data->total_written += bytes_written;
 921   g_assert (data->total_written <= data->blob_size);
 922   if (data->total_written == data->blob_size)
 923     {
 924       g_simple_async_result_complete (simple);
 925       g_object_unref (simple);
 926       goto out;
 927     }
 928
 929   write_message_continue_writing (data);
 930
 931  out:
 932   ;
 933 }
 934
 935 /* called in private thread shared by all GDBusConnection instances (without write-lock held) */
 936 static gboolean
 937 on_socket_ready (GSocket      *socket,
 938                  GIOCondition  condition,
 939                  gpointer      user_data)
 940 {
 941   MessageToWriteData *data = user_data;
 942   write_message_continue_writing (data);
 943   return FALSE; /* remove source */
 944 }
 945
 946 /* called in private thread shared by all GDBusConnection instances (without write-lock held) */
 947 static void
 948 write_message_continue_writing (MessageToWriteData *data)
 949 {
 950   GOutputStream *ostream;
 951   GSimpleAsyncResult *simple;
 952 #ifdef G_OS_UNIX
 953   GUnixFDList *fd_list;
 954 #endif
 955
 956   /* Note: we can't access data->simple after calling g_async_result_complete () because the
 957    * callback can free @data and we're not completing in idle. So use a copy of the pointer.
 958    */
 959   simple = data->simple;
 960
 961   ostream = g_io_stream_get_output_stream (data->worker->stream);
 962 #ifdef G_OS_UNIX
 963   fd_list = g_dbus_message_get_unix_fd_list (data->message);
 964 #endif
 965
 966   g_assert (!g_output_stream_has_pending (ostream));
 967   g_assert_cmpint (data->total_written, <, data->blob_size);
 968
 969   if (FALSE)
 970     {
 971     }
 972 #ifdef G_OS_UNIX
 973   else if (G_IS_SOCKET_OUTPUT_STREAM (ostream) && data->total_written == 0)
 974     {
 975       GOutputVector vector;
 976       GSocketControlMessage *control_message;
 977       gssize bytes_written;
 978       GError *error;
 979
 980       vector.buffer = data->blob;
 981       vector.size = data->blob_size;
 982
 983       control_message = NULL;
 984       if (fd_list != NULL && g_unix_fd_list_get_length (fd_list) > 0)
 985         {
 986           if (!(data->worker->capabilities & G_DBUS_CAPABILITY_FLAGS_UNIX_FD_PASSING))
 987             {
 988               g_simple_async_result_set_error (simple,
 989                                                G_IO_ERROR,
 990                                                G_IO_ERROR_FAILED,
 991                                                "Tried sending a file descriptor but remote peer does not support this capability");
 992               g_simple_async_result_complete (simple);
 993               g_object_unref (simple);
 994               goto out;
 995             }
 996           control_message = g_unix_fd_message_new_with_fd_list (fd_list);
 997         }
 998
 999       error = NULL;
1000       bytes_written = g_socket_send_message (data->worker->socket,
1001                                              NULL, /* address */
1002                                              &vector,
1003                                              1,
1004                                              control_message != NULL ? &control_message : NULL,
1005                                              control_message != NULL ? 1 : 0,
1006                                              G_SOCKET_MSG_NONE,
1007                                              data->worker->cancellable,
1008                                              &error);
1009       if (control_message != NULL)
1010         g_object_unref (control_message);
1011
1012       if (bytes_written == -1)
1013         {
1014           /* Handle WOULD_BLOCK by waiting until there's room in the buffer */
1015           if (g_error_matches (error, G_IO_ERROR, G_IO_ERROR_WOULD_BLOCK))
1016             {
1017               GSource *source;
1018               source = g_socket_create_source (data->worker->socket,
1019                                                G_IO_OUT | G_IO_HUP | G_IO_ERR,
1020                                                data->worker->cancellable);
1021               g_source_set_callback (source,
1022                                      (GSourceFunc) on_socket_ready,
1023                                      data,
1024                                      NULL); /* GDestroyNotify */
1025               g_source_attach (source, g_main_context_get_thread_default ());
1026               g_source_unref (source);
1027               g_error_free (error);
1028               goto out;
1029             }
1030           g_simple_async_result_set_from_error (simple, error);
1031           g_error_free (error);
1032           g_simple_async_result_complete (simple);
1033           g_object_unref (simple);
1034           goto out;
1035         }
1036       g_assert (bytes_written > 0); /* zero is never returned */
1037
1038       write_message_print_transport_debug (bytes_written, data);
1039
1040       data->total_written += bytes_written;
1041       g_assert (data->total_written <= data->blob_size);
1042       if (data->total_written == data->blob_size)
1043         {
1044           g_simple_async_result_complete (simple);
1045           g_object_unref (simple);
1046           goto out;
1047         }
1048
1049       write_message_continue_writing (data);
1050     }
1051 #endif
1052   else
1053     {
1054 #ifdef G_OS_UNIX
1055       if (fd_list != NULL)
1056         {
1057           g_simple_async_result_set_error (simple,
1058                                            G_IO_ERROR,
1059                                            G_IO_ERROR_FAILED,
1060                                            "Tried sending a file descriptor on unsupported stream of type %s",
1061                                            g_type_name (G_TYPE_FROM_INSTANCE (ostream)));
1062           g_simple_async_result_complete (simple);
1063           g_object_unref (simple);
1064           goto out;
1065         }
1066 #endif
1067
1068       g_output_stream_write_async (ostream,
1069                                    (const gchar *) data->blob + data->total_written,
1070                                    data->blob_size - data->total_written,
1071                                    G_PRIORITY_DEFAULT,
1072                                    data->worker->cancellable,
1073                                    write_message_async_cb,
1074                                    data);
1075     }
1076  out:
1077   ;
1078 }
1079
1080 /* called in private thread shared by all GDBusConnection instances (without write-lock held) */
1081 static void
1082 write_message_async (GDBusWorker         *worker,
1083                      MessageToWriteData  *data,
1084                      GAsyncReadyCallback  callback,
1085                      gpointer             user_data)
1086 {
1087   data->simple = g_simple_async_result_new (NULL,
1088                                             callback,
1089                                             user_data,
1090                                             write_message_async);
1091   data->total_written = 0;
1092   write_message_continue_writing (data);
1093 }
1094
1095 /* called in private thread shared by all GDBusConnection instances (without write-lock held) */
1096 static gboolean
1097 write_message_finish (GAsyncResult   *res,
1098                       GError        **error)
1099 {
1100   g_warn_if_fail (g_simple_async_result_get_source_tag (G_SIMPLE_ASYNC_RESULT (res)) == write_message_async);
1101   if (g_simple_async_result_propagate_error (G_SIMPLE_ASYNC_RESULT (res), error))
1102     return FALSE;
1103   else
1104     return TRUE;
1105 }
1106 /* ---------------------------------------------------------------------------------------------------- */
1107
1108 static void maybe_write_next_message (GDBusWorker *worker);
1109
1110 typedef struct
1111 {
1112   GDBusWorker *worker;
1113   GList *flushers;
1114 } FlushAsyncData;
1115
1116 /* called in private thread shared by all GDBusConnection instances (without write-lock held) */
1117 static void
1118 ostream_flush_cb (GObject      *source_object,
1119                   GAsyncResult *res,
1120                   gpointer      user_data)
1121 {
1122   FlushAsyncData *data = user_data;
1123   GError *error;
1124   GList *l;
1125
1126   error = NULL;
1127   g_output_stream_flush_finish (G_OUTPUT_STREAM (source_object),
1128                                 res,
1129                                 &error);
1130
1131   if (error == NULL)
1132     {
1133       if (G_UNLIKELY (_g_dbus_debug_transport ()))
1134         {
1135           _g_dbus_debug_print_lock ();
1136           g_print ("========================================================================\n"
1137                    "GDBus-debug:Transport:\n"
1138                    "  ---- FLUSHED stream of type %s\n",
1139                    g_type_name (G_TYPE_FROM_INSTANCE (g_io_stream_get_output_stream (data->worker->stream))));
1140           _g_dbus_debug_print_unlock ();
1141         }
1142     }
1143
1144   g_assert (data->flushers != NULL);
1145   for (l = data->flushers; l != NULL; l = l->next)
1146     {
1147       FlushData *f = l->data;
1148
1149       f->error = error != NULL ? g_error_copy (error) : NULL;
1150
1151       g_mutex_lock (f->mutex);
1152       g_cond_signal (f->cond);
1153       g_mutex_unlock (f->mutex);
1154     }
1155   g_list_free (data->flushers);
1156
1157   if (error != NULL)
1158     g_error_free (error);
1159
1160   /* OK, cool, finally kick off the next write */
1161   maybe_write_next_message (data->worker);
1162
1163   _g_dbus_worker_unref (data->worker);
1164   g_free (data);
1165 }
1166
1167 /* called in private thread shared by all GDBusConnection instances (without write-lock held) */
1168 static void
1169 message_written (GDBusWorker *worker,
1170                  MessageToWriteData *message_data)
1171 {
1172   GList *l;
1173   GList *ll;
1174   GList *flushers;
1175
1176   /* first log the fact that we wrote a message */
1177   if (G_UNLIKELY (_g_dbus_debug_message ()))
1178     {
1179       gchar *s;
1180       _g_dbus_debug_print_lock ();
1181       g_print ("========================================================================\n"
1182                "GDBus-debug:Message:\n"
1183                "  >>>> SENT D-Bus message (%" G_GSIZE_FORMAT " bytes)\n",
1184                message_data->blob_size);
1185       s = g_dbus_message_print (message_data->message, 2);
1186       g_print ("%s", s);
1187       g_free (s);
1188       if (G_UNLIKELY (_g_dbus_debug_payload ()))
1189         {
1190           s = _g_dbus_hexdump (message_data->blob, message_data->blob_size, 2);
1191           g_print ("%s\n", s);
1192           g_free (s);
1193         }
1194       _g_dbus_debug_print_unlock ();
1195     }
1196
1197   /* then first wake up pending flushes and, if needed, flush the stream */
1198   flushers = NULL;
1199   g_mutex_lock (worker->write_lock);
1200   worker->write_num_messages_written += 1;
1201   for (l = worker->write_pending_flushes; l != NULL; l = ll)
1202     {
1203       FlushData *f = l->data;
1204       ll = l->next;
1205
1206       if (f->number_to_wait_for == worker->write_num_messages_written)
1207         {
1208           flushers = g_list_append (flushers, f);
1209           worker->write_pending_flushes = g_list_delete_link (worker->write_pending_flushes, l);
1210         }
1211     }
1212   g_mutex_unlock (worker->write_lock);
1213
1214   if (flushers != NULL)
1215     {
1216       FlushAsyncData *data;
1217       data = g_new0 (FlushAsyncData, 1);
1218       data->worker = _g_dbus_worker_ref (worker);
1219       data->flushers = flushers;
1220       /* flush the stream before writing the next message */
1221       g_output_stream_flush_async (g_io_stream_get_output_stream (worker->stream),
1222                                    G_PRIORITY_DEFAULT,
1223                                    worker->cancellable,
1224                                    ostream_flush_cb,
1225                                    data);
1226     }
1227   else
1228     {
1229       /* kick off the next write! */
1230       maybe_write_next_message (worker);
1231     }
1232 }
1233
1234 /* called in private thread shared by all GDBusConnection instances (without write-lock held) */
1235 static void
1236 write_message_cb (GObject       *source_object,
1237                   GAsyncResult  *res,
1238                   gpointer       user_data)
1239 {
1240   MessageToWriteData *data = user_data;
1241   GError *error;
1242
1243   g_mutex_lock (data->worker->write_lock);
1244   data->worker->num_writes_pending -= 1;
1245   g_mutex_unlock (data->worker->write_lock);
1246
1247   error = NULL;
1248   if (!write_message_finish (res, &error))
1249     {
1250       /* TODO: handle */
1251       _g_dbus_worker_emit_disconnected (data->worker, TRUE, error);
1252       g_error_free (error);
1253     }
1254
1255   /* this function will also kick of the next write (it might need to
1256    * flush so writing the next message might happen much later
1257    * e.g. async)
1258    */
1259   message_written (data->worker, data);
1260
1261   message_to_write_data_free (data);
1262 }
1263
1264 /* called in private thread shared by all GDBusConnection instances (without write-lock held) */
1265 static void
1266 maybe_write_next_message (GDBusWorker *worker)
1267 {
1268   MessageToWriteData *data;
1269
1270  write_next:
1271
1272   g_mutex_lock (worker->write_lock);
1273   data = g_queue_pop_head (worker->write_queue);
1274   if (data != NULL)
1275     worker->num_writes_pending += 1;
1276   g_mutex_unlock (worker->write_lock);
1277
1278   /* Note that write_lock is only used for protecting the @write_queue
1279    * and @num_writes_pending fields of the GDBusWorker struct ... which we
1280    * need to modify from arbitrary threads in _g_dbus_worker_send_message().
1281    *
1282    * Therefore, it's fine to drop it here when calling back into user
1283    * code and then writing the message out onto the GIOStream since this
1284    * function only runs on the worker thread.
1285    */
1286   if (data != NULL)
1287     {
1288       GDBusMessage *old_message;
1289       guchar *new_blob;
1290       gsize new_blob_size;
1291       GError *error;
1292
1293       old_message = data->message;
1294       data->message = _g_dbus_worker_emit_message_about_to_be_sent (worker, data->message);
1295       if (data->message == old_message)
1296         {
1297           /* filters had no effect - do nothing */
1298         }
1299       else if (data->message == NULL)
1300         {
1301           /* filters dropped message */
1302           g_mutex_lock (worker->write_lock);
1303           worker->num_writes_pending -= 1;
1304           g_mutex_unlock (worker->write_lock);
1305           message_to_write_data_free (data);
1306           goto write_next;
1307         }
1308       else
1309         {
1310           /* filters altered the message -> reencode */
1311           error = NULL;
1312           new_blob = g_dbus_message_to_blob (data->message,
1313                                              &new_blob_size,
1314                                              worker->capabilities,
1315                                              &error);
1316           if (new_blob == NULL)
1317             {
1318               /* if filter make the GDBusMessage unencodeable, just complain on stderr and send
1319                * the old message instead
1320                */
1321               g_warning ("Error encoding GDBusMessage with serial %d altered by filter function: %s",
1322                          g_dbus_message_get_serial (data->message),
1323                          error->message);
1324               g_error_free (error);
1325             }
1326           else
1327             {
1328               g_free (data->blob);
1329               data->blob = (gchar *) new_blob;
1330               data->blob_size = new_blob_size;
1331             }
1332         }
1333
1334       write_message_async (worker,
1335                            data,
1336                            write_message_cb,
1337                            data);
1338     }
1339 }
1340
1341 /* called in private thread shared by all GDBusConnection instances (without write-lock held) */
1342 static gboolean
1343 write_message_in_idle_cb (gpointer user_data)
1344 {
1345   GDBusWorker *worker = user_data;
1346   if (worker->num_writes_pending == 0)
1347     maybe_write_next_message (worker);
1348   return FALSE;
1349 }
1350
1351 /* ---------------------------------------------------------------------------------------------------- */
1352
1353 /* can be called from any thread - steals blob */
1354 void
1355 _g_dbus_worker_send_message (GDBusWorker    *worker,
1356                              GDBusMessage   *message,
1357                              gchar          *blob,
1358                              gsize           blob_len)
1359 {
1360   MessageToWriteData *data;
1361
1362   g_return_if_fail (G_IS_DBUS_MESSAGE (message));
1363   g_return_if_fail (blob != NULL);
1364   g_return_if_fail (blob_len > 16);
1365
1366   data = g_new0 (MessageToWriteData, 1);
1367   data->worker = _g_dbus_worker_ref (worker);
1368   data->message = g_object_ref (message);
1369   data->blob = blob; /* steal! */
1370   data->blob_size = blob_len;
1371
1372   g_mutex_lock (worker->write_lock);
1373   g_queue_push_tail (worker->write_queue, data);
1374   if (worker->num_writes_pending == 0)
1375     {
1376       GSource *idle_source;
1377       idle_source = g_idle_source_new ();
1378       g_source_set_priority (idle_source, G_PRIORITY_DEFAULT);
1379       g_source_set_callback (idle_source,
1380                              write_message_in_idle_cb,
1381                              _g_dbus_worker_ref (worker),
1382                              (GDestroyNotify) _g_dbus_worker_unref);
1383       g_source_attach (idle_source, shared_thread_data->context);
1384       g_source_unref (idle_source);
1385     }
1386   g_mutex_unlock (worker->write_lock);
1387 }
1388
1389 /* ---------------------------------------------------------------------------------------------------- */
1390
1391 static void
1392 _g_dbus_worker_thread_begin_func (gpointer user_data)
1393 {
1394   GDBusWorker *worker = user_data;
1395
1396   worker->thread = g_thread_self ();
1397
1398   /* begin reading */
1399   _g_dbus_worker_do_read (worker);
1400 }
1401
1402 GDBusWorker *
1403 _g_dbus_worker_new (GIOStream                              *stream,
1404                     GDBusCapabilityFlags                    capabilities,
1405                     gboolean                                initially_frozen,
1406                     GDBusWorkerMessageReceivedCallback      message_received_callback,
1407                     GDBusWorkerMessageAboutToBeSentCallback message_about_to_be_sent_callback,
1408                     GDBusWorkerDisconnectedCallback         disconnected_callback,
1409                     gpointer                                user_data)
1410 {
1411   GDBusWorker *worker;
1412
1413   g_return_val_if_fail (G_IS_IO_STREAM (stream), NULL);
1414   g_return_val_if_fail (message_received_callback != NULL, NULL);
1415   g_return_val_if_fail (message_about_to_be_sent_callback != NULL, NULL);
1416   g_return_val_if_fail (disconnected_callback != NULL, NULL);
1417
1418   worker = g_new0 (GDBusWorker, 1);
1419   worker->ref_count = 1;
1420
1421   worker->read_lock = g_mutex_new ();
1422   worker->message_received_callback = message_received_callback;
1423   worker->message_about_to_be_sent_callback = message_about_to_be_sent_callback;
1424   worker->disconnected_callback = disconnected_callback;
1425   worker->user_data = user_data;
1426   worker->stream = g_object_ref (stream);
1427   worker->capabilities = capabilities;
1428   worker->cancellable = g_cancellable_new ();
1429
1430   worker->frozen = initially_frozen;
1431   worker->received_messages_while_frozen = g_queue_new ();
1432
1433   worker->write_lock = g_mutex_new ();
1434   worker->write_queue = g_queue_new ();
1435
1436   if (G_IS_SOCKET_CONNECTION (worker->stream))
1437     worker->socket = g_socket_connection_get_socket (G_SOCKET_CONNECTION (worker->stream));
1438
1439   _g_dbus_shared_thread_ref (_g_dbus_worker_thread_begin_func, worker);
1440
1441   return worker;
1442 }
1443
1444 /* ---------------------------------------------------------------------------------------------------- */
1445
1446 /* This can be called from any thread - frees worker. Note that
1447  * callbacks might still happen if called from another thread than the
1448  * worker - use your own synchronization primitive in the callbacks.
1449  */
1450 void
1451 _g_dbus_worker_stop (GDBusWorker *worker)
1452 {
1453   worker->stopped = TRUE;
1454   g_cancellable_cancel (worker->cancellable);
1455   _g_dbus_worker_unref (worker);
1456 }
1457
1458 /* ---------------------------------------------------------------------------------------------------- */
1459
1460 /* can be called from any thread (except the worker thread) - blocks
1461  * calling thread until all queued outgoing messages are written and
1462  * the transport has been flushed
1463  */
1464 gboolean
1465 _g_dbus_worker_flush_sync (GDBusWorker    *worker,
1466                            GCancellable   *cancellable,
1467                            GError        **error)
1468 {
1469   gboolean ret;
1470   FlushData *data;
1471
1472   data = NULL;
1473   ret = TRUE;
1474
1475   /* if the queue is empty, there's nothing to wait for */
1476   g_mutex_lock (worker->write_lock);
1477   if (g_queue_get_length (worker->write_queue) > 0)
1478     {
1479       data = g_new0 (FlushData, 1);
1480       data->mutex = g_mutex_new ();
1481       data->cond = g_cond_new ();
1482       data->number_to_wait_for = worker->write_num_messages_written + g_queue_get_length (worker->write_queue);
1483       g_mutex_lock (data->mutex);
1484       worker->write_pending_flushes = g_list_prepend (worker->write_pending_flushes, data);
1485     }
1486   g_mutex_unlock (worker->write_lock);
1487
1488   if (data != NULL)
1489     {
1490       g_cond_wait (data->cond, data->mutex);
1491       g_mutex_unlock (data->mutex);
1492
1493       /* note:the element is removed from worker->write_pending_flushes in flush_cb() above */
1494       g_cond_free (data->cond);
1495       g_mutex_free (data->mutex);
1496       if (data->error != NULL)
1497         {
1498           ret = FALSE;
1499           g_propagate_error (error, data->error);
1500         }
1501       g_free (data);
1502     }
1503
1504   return ret;
1505 }
1506
1507 /* ---------------------------------------------------------------------------------------------------- */
1508
1509 #define G_DBUS_DEBUG_AUTHENTICATION (1<<0)
1510 #define G_DBUS_DEBUG_TRANSPORT      (1<<1)
1511 #define G_DBUS_DEBUG_MESSAGE        (1<<2)
1512 #define G_DBUS_DEBUG_PAYLOAD        (1<<3)
1513 #define G_DBUS_DEBUG_CALL           (1<<4)
1514 #define G_DBUS_DEBUG_SIGNAL         (1<<5)
1515 #define G_DBUS_DEBUG_INCOMING       (1<<6)
1516 #define G_DBUS_DEBUG_RETURN         (1<<7)
1517 #define G_DBUS_DEBUG_EMISSION       (1<<8)
1518 #define G_DBUS_DEBUG_ADDRESS        (1<<9)
1519
1520 static gint _gdbus_debug_flags = 0;
1521
1522 gboolean
1523 _g_dbus_debug_authentication (void)
1524 {
1525   _g_dbus_initialize ();
1526   return (_gdbus_debug_flags & G_DBUS_DEBUG_AUTHENTICATION) != 0;
1527 }
1528
1529 gboolean
1530 _g_dbus_debug_transport (void)
1531 {
1532   _g_dbus_initialize ();
1533   return (_gdbus_debug_flags & G_DBUS_DEBUG_TRANSPORT) != 0;
1534 }
1535
1536 gboolean
1537 _g_dbus_debug_message (void)
1538 {
1539   _g_dbus_initialize ();
1540   return (_gdbus_debug_flags & G_DBUS_DEBUG_MESSAGE) != 0;
1541 }
1542
1543 gboolean
1544 _g_dbus_debug_payload (void)
1545 {
1546   _g_dbus_initialize ();
1547   return (_gdbus_debug_flags & G_DBUS_DEBUG_PAYLOAD) != 0;
1548 }
1549
1550 gboolean
1551 _g_dbus_debug_call (void)
1552 {
1553   _g_dbus_initialize ();
1554   return (_gdbus_debug_flags & G_DBUS_DEBUG_CALL) != 0;
1555 }
1556
1557 gboolean
1558 _g_dbus_debug_signal (void)
1559 {
1560   _g_dbus_initialize ();
1561   return (_gdbus_debug_flags & G_DBUS_DEBUG_SIGNAL) != 0;
1562 }
1563
1564 gboolean
1565 _g_dbus_debug_incoming (void)
1566 {
1567   _g_dbus_initialize ();
1568   return (_gdbus_debug_flags & G_DBUS_DEBUG_INCOMING) != 0;
1569 }
1570
1571 gboolean
1572 _g_dbus_debug_return (void)
1573 {
1574   _g_dbus_initialize ();
1575   return (_gdbus_debug_flags & G_DBUS_DEBUG_RETURN) != 0;
1576 }
1577
1578 gboolean
1579 _g_dbus_debug_emission (void)
1580 {
1581   _g_dbus_initialize ();
1582   return (_gdbus_debug_flags & G_DBUS_DEBUG_EMISSION) != 0;
1583 }
1584
1585 gboolean
1586 _g_dbus_debug_address (void)
1587 {
1588   _g_dbus_initialize ();
1589   return (_gdbus_debug_flags & G_DBUS_DEBUG_ADDRESS) != 0;
1590 }
1591
1592 G_LOCK_DEFINE_STATIC (print_lock);
1593
1594 void
1595 _g_dbus_debug_print_lock (void)
1596 {
1597   G_LOCK (print_lock);
1598 }
1599
1600 void
1601 _g_dbus_debug_print_unlock (void)
1602 {
1603   G_UNLOCK (print_lock);
1604 }
1605
1606 /*
1607  * _g_dbus_initialize:
1608  *
1609  * Does various one-time init things such as
1610  *
1611  *  - registering the G_DBUS_ERROR error domain
1612  *  - parses the G_DBUS_DEBUG environment variable
1613  */
1614 void
1615 _g_dbus_initialize (void)
1616 {
1617   static volatile gsize initialized = 0;
1618
1619   if (g_once_init_enter (&initialized))
1620     {
1621       volatile GQuark g_dbus_error_domain;
1622       const gchar *debug;
1623
1624       g_dbus_error_domain = G_DBUS_ERROR;
1625
1626       debug = g_getenv ("G_DBUS_DEBUG");
1627       if (debug != NULL)
1628         {
1629           const GDebugKey keys[] = {
1630             { "authentication", G_DBUS_DEBUG_AUTHENTICATION },
1631             { "transport",      G_DBUS_DEBUG_TRANSPORT      },
1632             { "message",        G_DBUS_DEBUG_MESSAGE        },
1633             { "payload",        G_DBUS_DEBUG_PAYLOAD        },
1634             { "call",           G_DBUS_DEBUG_CALL           },
1635             { "signal",         G_DBUS_DEBUG_SIGNAL         },
1636             { "incoming",       G_DBUS_DEBUG_INCOMING       },
1637             { "return",         G_DBUS_DEBUG_RETURN         },
1638             { "emission",       G_DBUS_DEBUG_EMISSION       },
1639             { "address",        G_DBUS_DEBUG_ADDRESS        }
1640           };
1641
1642           _gdbus_debug_flags = g_parse_debug_string (debug, keys, G_N_ELEMENTS (keys));
1643           if (_gdbus_debug_flags & G_DBUS_DEBUG_PAYLOAD)
1644             _gdbus_debug_flags |= G_DBUS_DEBUG_MESSAGE;
1645         }
1646
1647       g_once_init_leave (&initialized, 1);
1648     }
1649 }
1650
1651 /* ---------------------------------------------------------------------------------------------------- */
1652
1653 GVariantType *
1654 _g_dbus_compute_complete_signature (GDBusArgInfo **args)
1655 {
1656   const GVariantType *arg_types[256];
1657   guint n;
1658
1659   if (args)
1660     for (n = 0; args[n] != NULL; n++)
1661       {
1662         /* DBus places a hard limit of 255 on signature length.
1663          * therefore number of args must be less than 256.
1664          */
1665         g_assert (n < 256);
1666
1667         arg_types[n] = G_VARIANT_TYPE (args[n]->signature);
1668
1669         if G_UNLIKELY (arg_types[n] == NULL)
1670           return NULL;
1671       }
1672   else
1673     n = 0;
1674
1675   return g_variant_type_new_tuple (arg_types, n);
1676 }
1677
1678 /* ---------------------------------------------------------------------------------------------------- */
1679
1680 #ifdef G_OS_WIN32
1681
1682 extern BOOL WINAPI ConvertSidToStringSidA (PSID Sid, LPSTR *StringSid);
1683
1684 gchar *
1685 _g_dbus_win32_get_user_sid (void)
1686 {
1687   HANDLE h;
1688   TOKEN_USER *user;
1689   DWORD token_information_len;
1690   PSID psid;
1691   gchar *sid;
1692   gchar *ret;
1693
1694   ret = NULL;
1695   user = NULL;
1696   h = INVALID_HANDLE_VALUE;
1697
1698   if (!OpenProcessToken (GetCurrentProcess (), TOKEN_QUERY, &h))
1699     {
1700       g_warning ("OpenProcessToken failed with error code %d", (gint) GetLastError ());
1701       goto out;
1702     }
1703
1704   /* Get length of buffer */
1705   token_information_len = 0;
1706   if (!GetTokenInformation (h, TokenUser, NULL, 0, &token_information_len))
1707     {
1708       if (GetLastError () != ERROR_INSUFFICIENT_BUFFER)
1709         {
1710           g_warning ("GetTokenInformation() failed with error code %d", (gint) GetLastError ());
1711           goto out;
1712         }
1713     }
1714   user = g_malloc (token_information_len);
1715   if (!GetTokenInformation (h, TokenUser, user, token_information_len, &token_information_len))
1716     {
1717       g_warning ("GetTokenInformation() failed with error code %d", (gint) GetLastError ());
1718       goto out;
1719     }
1720
1721   psid = user->User.Sid;
1722   if (!IsValidSid (psid))
1723     {
1724       g_warning ("Invalid SID");
1725       goto out;
1726     }
1727
1728   if (!ConvertSidToStringSidA (psid, &sid))
1729     {
1730       g_warning ("Invalid SID");
1731       goto out;
1732     }
1733
1734   ret = g_strdup (sid);
1735   LocalFree (sid);
1736
1737 out:
1738   g_free (user);
1739   if (h != INVALID_HANDLE_VALUE)
1740     CloseHandle (h);
1741   return ret;
1742 }
1743 #endif
1744
1745 /* ---------------------------------------------------------------------------------------------------- */
1746
1747 gchar *
1748 _g_dbus_get_machine_id (GError **error)
1749 {
1750   gchar *ret;
1751   /* TODO: use PACKAGE_LOCALSTATEDIR ? */
1752   ret = NULL;
1753   if (!g_file_get_contents ("/var/lib/dbus/machine-id",
1754                             &ret,
1755                             NULL,
1756                             error))
1757     {
1758       g_prefix_error (error, _("Unable to load /var/lib/dbus/machine-id: "));
1759     }
1760   else
1761     {
1762       /* TODO: validate value */
1763       g_strstrip (ret);
1764     }
1765   return ret;
1766 }
1767
1768 /* ---------------------------------------------------------------------------------------------------- */
1769
1770 gchar *
1771 _g_dbus_enum_to_string (GType enum_type, gint value)
1772 {
1773   gchar *ret;
1774   GEnumClass *klass;
1775   GEnumValue *enum_value;
1776
1777   klass = g_type_class_ref (enum_type);
1778   enum_value = g_enum_get_value (klass, value);
1779   if (enum_value != NULL)
1780     ret = g_strdup (enum_value->value_nick);
1781   else
1782     ret = g_strdup_printf ("unknown (value %d)", value);
1783   g_type_class_unref (klass);
1784   return ret;
1785 }
1786
1787 /* ---------------------------------------------------------------------------------------------------- */
1788
1789 static void
1790 write_message_print_transport_debug (gssize bytes_written,
1791                                      MessageToWriteData *data)
1792 {
1793   if (G_LIKELY (!_g_dbus_debug_transport ()))
1794     goto out;
1795
1796   _g_dbus_debug_print_lock ();
1797   g_print ("========================================================================\n"
1798            "GDBus-debug:Transport:\n"
1799            "  >>>> WROTE %" G_GSIZE_FORMAT " bytes of message with serial %d and\n"
1800            "       size %" G_GSIZE_FORMAT " from offset %" G_GSIZE_FORMAT " on a %s\n",
1801            bytes_written,
1802            g_dbus_message_get_serial (data->message),
1803            data->blob_size,
1804            data->total_written,
1805            g_type_name (G_TYPE_FROM_INSTANCE (g_io_stream_get_output_stream (data->worker->stream))));
1806   _g_dbus_debug_print_unlock ();
1807  out:
1808   ;
1809 }
1810
1811 /* ---------------------------------------------------------------------------------------------------- */
1812
1813 static void
1814 read_message_print_transport_debug (gssize bytes_read,
1815                                     GDBusWorker *worker)
1816 {
1817   gsize size;
1818   gint32 serial;
1819   gint32 message_length;
1820
1821   if (G_LIKELY (!_g_dbus_debug_transport ()))
1822     goto out;
1823
1824   size = bytes_read + worker->read_buffer_cur_size;
1825   serial = 0;
1826   message_length = 0;
1827   if (size >= 16)
1828     message_length = g_dbus_message_bytes_needed ((guchar *) worker->read_buffer, size, NULL);
1829   if (size >= 1)
1830     {
1831       switch (worker->read_buffer[0])
1832         {
1833         case 'l':
1834           if (size >= 12)
1835             serial = GUINT32_FROM_LE (((guint32 *) worker->read_buffer)[2]);
1836           break;
1837         case 'B':
1838           if (size >= 12)
1839             serial = GUINT32_FROM_BE (((guint32 *) worker->read_buffer)[2]);
1840           break;
1841         default:
1842           /* an error will be set elsewhere if this happens */
1843           goto out;
1844         }
1845     }
1846
1847     _g_dbus_debug_print_lock ();
1848   g_print ("========================================================================\n"
1849            "GDBus-debug:Transport:\n"
1850            "  <<<< READ %" G_GSIZE_FORMAT " bytes of message with serial %d and\n"
1851            "       size %d to offset %" G_GSIZE_FORMAT " from a %s\n",
1852            bytes_read,
1853            serial,
1854            message_length,
1855            worker->read_buffer_cur_size,
1856            g_type_name (G_TYPE_FROM_INSTANCE (g_io_stream_get_input_stream (worker->stream))));
1857   _g_dbus_debug_print_unlock ();
1858  out:
1859   ;
1860 }