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   if (data->message)
 880     g_object_unref (data->message);
 881   g_free (data->blob);
 882   g_free (data);
 883 }
 884
 885 /* ---------------------------------------------------------------------------------------------------- */
 886
 887 static void write_message_continue_writing (MessageToWriteData *data);
 888
 889 /* called in private thread shared by all GDBusConnection instances (without write-lock held) */
 890 static void
 891 write_message_async_cb (GObject      *source_object,
 892                         GAsyncResult *res,
 893                         gpointer      user_data)
 894 {
 895   MessageToWriteData *data = user_data;
 896   GSimpleAsyncResult *simple;
 897   gssize bytes_written;
 898   GError *error;
 899
 900   /* Note: we can't access data->simple after calling g_async_result_complete () because the
 901    * callback can free @data and we're not completing in idle. So use a copy of the pointer.
 902    */
 903   simple = data->simple;
 904
 905   error = NULL;
 906   bytes_written = g_output_stream_write_finish (G_OUTPUT_STREAM (source_object),
 907                                                 res,
 908                                                 &error);
 909   if (bytes_written == -1)
 910     {
 911       g_simple_async_result_set_from_error (simple, error);
 912       g_error_free (error);
 913       g_simple_async_result_complete (simple);
 914       g_object_unref (simple);
 915       goto out;
 916     }
 917   g_assert (bytes_written > 0); /* zero is never returned */
 918
 919   write_message_print_transport_debug (bytes_written, data);
 920
 921   data->total_written += bytes_written;
 922   g_assert (data->total_written <= data->blob_size);
 923   if (data->total_written == data->blob_size)
 924     {
 925       g_simple_async_result_complete (simple);
 926       g_object_unref (simple);
 927       goto out;
 928     }
 929
 930   write_message_continue_writing (data);
 931
 932  out:
 933   ;
 934 }
 935
 936 /* called in private thread shared by all GDBusConnection instances (without write-lock held) */
 937 static gboolean
 938 on_socket_ready (GSocket      *socket,
 939                  GIOCondition  condition,
 940                  gpointer      user_data)
 941 {
 942   MessageToWriteData *data = user_data;
 943   write_message_continue_writing (data);
 944   return FALSE; /* remove source */
 945 }
 946
 947 /* called in private thread shared by all GDBusConnection instances (without write-lock held) */
 948 static void
 949 write_message_continue_writing (MessageToWriteData *data)
 950 {
 951   GOutputStream *ostream;
 952   GSimpleAsyncResult *simple;
 953 #ifdef G_OS_UNIX
 954   GUnixFDList *fd_list;
 955 #endif
 956
 957   /* Note: we can't access data->simple after calling g_async_result_complete () because the
 958    * callback can free @data and we're not completing in idle. So use a copy of the pointer.
 959    */
 960   simple = data->simple;
 961
 962   ostream = g_io_stream_get_output_stream (data->worker->stream);
 963 #ifdef G_OS_UNIX
 964   fd_list = g_dbus_message_get_unix_fd_list (data->message);
 965 #endif
 966
 967   g_assert (!g_output_stream_has_pending (ostream));
 968   g_assert_cmpint (data->total_written, <, data->blob_size);
 969
 970   if (FALSE)
 971     {
 972     }
 973 #ifdef G_OS_UNIX
 974   else if (G_IS_SOCKET_OUTPUT_STREAM (ostream) && data->total_written == 0)
 975     {
 976       GOutputVector vector;
 977       GSocketControlMessage *control_message;
 978       gssize bytes_written;
 979       GError *error;
 980
 981       vector.buffer = data->blob;
 982       vector.size = data->blob_size;
 983
 984       control_message = NULL;
 985       if (fd_list != NULL && g_unix_fd_list_get_length (fd_list) > 0)
 986         {
 987           if (!(data->worker->capabilities & G_DBUS_CAPABILITY_FLAGS_UNIX_FD_PASSING))
 988             {
 989               g_simple_async_result_set_error (simple,
 990                                                G_IO_ERROR,
 991                                                G_IO_ERROR_FAILED,
 992                                                "Tried sending a file descriptor but remote peer does not support this capability");
 993               g_simple_async_result_complete (simple);
 994               g_object_unref (simple);
 995               goto out;
 996             }
 997           control_message = g_unix_fd_message_new_with_fd_list (fd_list);
 998         }
 999
1000       error = NULL;
1001       bytes_written = g_socket_send_message (data->worker->socket,
1002                                              NULL, /* address */
1003                                              &vector,
1004                                              1,
1005                                              control_message != NULL ? &control_message : NULL,
1006                                              control_message != NULL ? 1 : 0,
1007                                              G_SOCKET_MSG_NONE,
1008                                              data->worker->cancellable,
1009                                              &error);
1010       if (control_message != NULL)
1011         g_object_unref (control_message);
1012
1013       if (bytes_written == -1)
1014         {
1015           /* Handle WOULD_BLOCK by waiting until there's room in the buffer */
1016           if (g_error_matches (error, G_IO_ERROR, G_IO_ERROR_WOULD_BLOCK))
1017             {
1018               GSource *source;
1019               source = g_socket_create_source (data->worker->socket,
1020                                                G_IO_OUT | G_IO_HUP | G_IO_ERR,
1021                                                data->worker->cancellable);
1022               g_source_set_callback (source,
1023                                      (GSourceFunc) on_socket_ready,
1024                                      data,
1025                                      NULL); /* GDestroyNotify */
1026               g_source_attach (source, g_main_context_get_thread_default ());
1027               g_source_unref (source);
1028               g_error_free (error);
1029               goto out;
1030             }
1031           g_simple_async_result_set_from_error (simple, error);
1032           g_error_free (error);
1033           g_simple_async_result_complete (simple);
1034           g_object_unref (simple);
1035           goto out;
1036         }
1037       g_assert (bytes_written > 0); /* zero is never returned */
1038
1039       write_message_print_transport_debug (bytes_written, data);
1040
1041       data->total_written += bytes_written;
1042       g_assert (data->total_written <= data->blob_size);
1043       if (data->total_written == data->blob_size)
1044         {
1045           g_simple_async_result_complete (simple);
1046           g_object_unref (simple);
1047           goto out;
1048         }
1049
1050       write_message_continue_writing (data);
1051     }
1052 #endif
1053   else
1054     {
1055 #ifdef G_OS_UNIX
1056       if (fd_list != NULL)
1057         {
1058           g_simple_async_result_set_error (simple,
1059                                            G_IO_ERROR,
1060                                            G_IO_ERROR_FAILED,
1061                                            "Tried sending a file descriptor on unsupported stream of type %s",
1062                                            g_type_name (G_TYPE_FROM_INSTANCE (ostream)));
1063           g_simple_async_result_complete (simple);
1064           g_object_unref (simple);
1065           goto out;
1066         }
1067 #endif
1068
1069       g_output_stream_write_async (ostream,
1070                                    (const gchar *) data->blob + data->total_written,
1071                                    data->blob_size - data->total_written,
1072                                    G_PRIORITY_DEFAULT,
1073                                    data->worker->cancellable,
1074                                    write_message_async_cb,
1075                                    data);
1076     }
1077  out:
1078   ;
1079 }
1080
1081 /* called in private thread shared by all GDBusConnection instances (without write-lock held) */
1082 static void
1083 write_message_async (GDBusWorker         *worker,
1084                      MessageToWriteData  *data,
1085                      GAsyncReadyCallback  callback,
1086                      gpointer             user_data)
1087 {
1088   data->simple = g_simple_async_result_new (NULL,
1089                                             callback,
1090                                             user_data,
1091                                             write_message_async);
1092   data->total_written = 0;
1093   write_message_continue_writing (data);
1094 }
1095
1096 /* called in private thread shared by all GDBusConnection instances (without write-lock held) */
1097 static gboolean
1098 write_message_finish (GAsyncResult   *res,
1099                       GError        **error)
1100 {
1101   g_warn_if_fail (g_simple_async_result_get_source_tag (G_SIMPLE_ASYNC_RESULT (res)) == write_message_async);
1102   if (g_simple_async_result_propagate_error (G_SIMPLE_ASYNC_RESULT (res), error))
1103     return FALSE;
1104   else
1105     return TRUE;
1106 }
1107 /* ---------------------------------------------------------------------------------------------------- */
1108
1109 static void maybe_write_next_message (GDBusWorker *worker);
1110
1111 typedef struct
1112 {
1113   GDBusWorker *worker;
1114   GList *flushers;
1115 } FlushAsyncData;
1116
1117 /* called in private thread shared by all GDBusConnection instances (without write-lock held) */
1118 static void
1119 ostream_flush_cb (GObject      *source_object,
1120                   GAsyncResult *res,
1121                   gpointer      user_data)
1122 {
1123   FlushAsyncData *data = user_data;
1124   GError *error;
1125   GList *l;
1126
1127   error = NULL;
1128   g_output_stream_flush_finish (G_OUTPUT_STREAM (source_object),
1129                                 res,
1130                                 &error);
1131
1132   if (error == NULL)
1133     {
1134       if (G_UNLIKELY (_g_dbus_debug_transport ()))
1135         {
1136           _g_dbus_debug_print_lock ();
1137           g_print ("========================================================================\n"
1138                    "GDBus-debug:Transport:\n"
1139                    "  ---- FLUSHED stream of type %s\n",
1140                    g_type_name (G_TYPE_FROM_INSTANCE (g_io_stream_get_output_stream (data->worker->stream))));
1141           _g_dbus_debug_print_unlock ();
1142         }
1143     }
1144
1145   g_assert (data->flushers != NULL);
1146   for (l = data->flushers; l != NULL; l = l->next)
1147     {
1148       FlushData *f = l->data;
1149
1150       f->error = error != NULL ? g_error_copy (error) : NULL;
1151
1152       g_mutex_lock (f->mutex);
1153       g_cond_signal (f->cond);
1154       g_mutex_unlock (f->mutex);
1155     }
1156   g_list_free (data->flushers);
1157
1158   if (error != NULL)
1159     g_error_free (error);
1160
1161   /* OK, cool, finally kick off the next write */
1162   maybe_write_next_message (data->worker);
1163
1164   _g_dbus_worker_unref (data->worker);
1165   g_free (data);
1166 }
1167
1168 /* called in private thread shared by all GDBusConnection instances (without write-lock held) */
1169 static void
1170 message_written (GDBusWorker *worker,
1171                  MessageToWriteData *message_data)
1172 {
1173   GList *l;
1174   GList *ll;
1175   GList *flushers;
1176
1177   /* first log the fact that we wrote a message */
1178   if (G_UNLIKELY (_g_dbus_debug_message ()))
1179     {
1180       gchar *s;
1181       _g_dbus_debug_print_lock ();
1182       g_print ("========================================================================\n"
1183                "GDBus-debug:Message:\n"
1184                "  >>>> SENT D-Bus message (%" G_GSIZE_FORMAT " bytes)\n",
1185                message_data->blob_size);
1186       s = g_dbus_message_print (message_data->message, 2);
1187       g_print ("%s", s);
1188       g_free (s);
1189       if (G_UNLIKELY (_g_dbus_debug_payload ()))
1190         {
1191           s = _g_dbus_hexdump (message_data->blob, message_data->blob_size, 2);
1192           g_print ("%s\n", s);
1193           g_free (s);
1194         }
1195       _g_dbus_debug_print_unlock ();
1196     }
1197
1198   /* then first wake up pending flushes and, if needed, flush the stream */
1199   flushers = NULL;
1200   g_mutex_lock (worker->write_lock);
1201   worker->write_num_messages_written += 1;
1202   for (l = worker->write_pending_flushes; l != NULL; l = ll)
1203     {
1204       FlushData *f = l->data;
1205       ll = l->next;
1206
1207       if (f->number_to_wait_for == worker->write_num_messages_written)
1208         {
1209           flushers = g_list_append (flushers, f);
1210           worker->write_pending_flushes = g_list_delete_link (worker->write_pending_flushes, l);
1211         }
1212     }
1213   g_mutex_unlock (worker->write_lock);
1214
1215   if (flushers != NULL)
1216     {
1217       FlushAsyncData *data;
1218       data = g_new0 (FlushAsyncData, 1);
1219       data->worker = _g_dbus_worker_ref (worker);
1220       data->flushers = flushers;
1221       /* flush the stream before writing the next message */
1222       g_output_stream_flush_async (g_io_stream_get_output_stream (worker->stream),
1223                                    G_PRIORITY_DEFAULT,
1224                                    worker->cancellable,
1225                                    ostream_flush_cb,
1226                                    data);
1227     }
1228   else
1229     {
1230       /* kick off the next write! */
1231       maybe_write_next_message (worker);
1232     }
1233 }
1234
1235 /* called in private thread shared by all GDBusConnection instances (without write-lock held) */
1236 static void
1237 write_message_cb (GObject       *source_object,
1238                   GAsyncResult  *res,
1239                   gpointer       user_data)
1240 {
1241   MessageToWriteData *data = user_data;
1242   GError *error;
1243
1244   g_mutex_lock (data->worker->write_lock);
1245   data->worker->num_writes_pending -= 1;
1246   g_mutex_unlock (data->worker->write_lock);
1247
1248   error = NULL;
1249   if (!write_message_finish (res, &error))
1250     {
1251       /* TODO: handle */
1252       _g_dbus_worker_emit_disconnected (data->worker, TRUE, error);
1253       g_error_free (error);
1254     }
1255
1256   /* this function will also kick of the next write (it might need to
1257    * flush so writing the next message might happen much later
1258    * e.g. async)
1259    */
1260   message_written (data->worker, data);
1261
1262   message_to_write_data_free (data);
1263 }
1264
1265 /* called in private thread shared by all GDBusConnection instances (without write-lock held) */
1266 static void
1267 maybe_write_next_message (GDBusWorker *worker)
1268 {
1269   MessageToWriteData *data;
1270
1271  write_next:
1272
1273   g_mutex_lock (worker->write_lock);
1274   data = g_queue_pop_head (worker->write_queue);
1275   if (data != NULL)
1276     worker->num_writes_pending += 1;
1277   g_mutex_unlock (worker->write_lock);
1278
1279   /* Note that write_lock is only used for protecting the @write_queue
1280    * and @num_writes_pending fields of the GDBusWorker struct ... which we
1281    * need to modify from arbitrary threads in _g_dbus_worker_send_message().
1282    *
1283    * Therefore, it's fine to drop it here when calling back into user
1284    * code and then writing the message out onto the GIOStream since this
1285    * function only runs on the worker thread.
1286    */
1287   if (data != NULL)
1288     {
1289       GDBusMessage *old_message;
1290       guchar *new_blob;
1291       gsize new_blob_size;
1292       GError *error;
1293
1294       old_message = data->message;
1295       data->message = _g_dbus_worker_emit_message_about_to_be_sent (worker, data->message);
1296       if (data->message == old_message)
1297         {
1298           /* filters had no effect - do nothing */
1299         }
1300       else if (data->message == NULL)
1301         {
1302           /* filters dropped message */
1303           g_mutex_lock (worker->write_lock);
1304           worker->num_writes_pending -= 1;
1305           g_mutex_unlock (worker->write_lock);
1306           message_to_write_data_free (data);
1307           goto write_next;
1308         }
1309       else
1310         {
1311           /* filters altered the message -> reencode */
1312           error = NULL;
1313           new_blob = g_dbus_message_to_blob (data->message,
1314                                              &new_blob_size,
1315                                              worker->capabilities,
1316                                              &error);
1317           if (new_blob == NULL)
1318             {
1319               /* if filter make the GDBusMessage unencodeable, just complain on stderr and send
1320                * the old message instead
1321                */
1322               g_warning ("Error encoding GDBusMessage with serial %d altered by filter function: %s",
1323                          g_dbus_message_get_serial (data->message),
1324                          error->message);
1325               g_error_free (error);
1326             }
1327           else
1328             {
1329               g_free (data->blob);
1330               data->blob = (gchar *) new_blob;
1331               data->blob_size = new_blob_size;
1332             }
1333         }
1334
1335       write_message_async (worker,
1336                            data,
1337                            write_message_cb,
1338                            data);
1339     }
1340 }
1341
1342 /* called in private thread shared by all GDBusConnection instances (without write-lock held) */
1343 static gboolean
1344 write_message_in_idle_cb (gpointer user_data)
1345 {
1346   GDBusWorker *worker = user_data;
1347   if (worker->num_writes_pending == 0)
1348     maybe_write_next_message (worker);
1349   return FALSE;
1350 }
1351
1352 /* ---------------------------------------------------------------------------------------------------- */
1353
1354 /* can be called from any thread - steals blob */
1355 void
1356 _g_dbus_worker_send_message (GDBusWorker    *worker,
1357                              GDBusMessage   *message,
1358                              gchar          *blob,
1359                              gsize           blob_len)
1360 {
1361   MessageToWriteData *data;
1362
1363   g_return_if_fail (G_IS_DBUS_MESSAGE (message));
1364   g_return_if_fail (blob != NULL);
1365   g_return_if_fail (blob_len > 16);
1366
1367   data = g_new0 (MessageToWriteData, 1);
1368   data->worker = _g_dbus_worker_ref (worker);
1369   data->message = g_object_ref (message);
1370   data->blob = blob; /* steal! */
1371   data->blob_size = blob_len;
1372
1373   g_mutex_lock (worker->write_lock);
1374   g_queue_push_tail (worker->write_queue, data);
1375   if (worker->num_writes_pending == 0)
1376     {
1377       GSource *idle_source;
1378       idle_source = g_idle_source_new ();
1379       g_source_set_priority (idle_source, G_PRIORITY_DEFAULT);
1380       g_source_set_callback (idle_source,
1381                              write_message_in_idle_cb,
1382                              _g_dbus_worker_ref (worker),
1383                              (GDestroyNotify) _g_dbus_worker_unref);
1384       g_source_attach (idle_source, shared_thread_data->context);
1385       g_source_unref (idle_source);
1386     }
1387   g_mutex_unlock (worker->write_lock);
1388 }
1389
1390 /* ---------------------------------------------------------------------------------------------------- */
1391
1392 static void
1393 _g_dbus_worker_thread_begin_func (gpointer user_data)
1394 {
1395   GDBusWorker *worker = user_data;
1396
1397   worker->thread = g_thread_self ();
1398
1399   /* begin reading */
1400   _g_dbus_worker_do_read (worker);
1401 }
1402
1403 GDBusWorker *
1404 _g_dbus_worker_new (GIOStream                              *stream,
1405                     GDBusCapabilityFlags                    capabilities,
1406                     gboolean                                initially_frozen,
1407                     GDBusWorkerMessageReceivedCallback      message_received_callback,
1408                     GDBusWorkerMessageAboutToBeSentCallback message_about_to_be_sent_callback,
1409                     GDBusWorkerDisconnectedCallback         disconnected_callback,
1410                     gpointer                                user_data)
1411 {
1412   GDBusWorker *worker;
1413
1414   g_return_val_if_fail (G_IS_IO_STREAM (stream), NULL);
1415   g_return_val_if_fail (message_received_callback != NULL, NULL);
1416   g_return_val_if_fail (message_about_to_be_sent_callback != NULL, NULL);
1417   g_return_val_if_fail (disconnected_callback != NULL, NULL);
1418
1419   worker = g_new0 (GDBusWorker, 1);
1420   worker->ref_count = 1;
1421
1422   worker->read_lock = g_mutex_new ();
1423   worker->message_received_callback = message_received_callback;
1424   worker->message_about_to_be_sent_callback = message_about_to_be_sent_callback;
1425   worker->disconnected_callback = disconnected_callback;
1426   worker->user_data = user_data;
1427   worker->stream = g_object_ref (stream);
1428   worker->capabilities = capabilities;
1429   worker->cancellable = g_cancellable_new ();
1430
1431   worker->frozen = initially_frozen;
1432   worker->received_messages_while_frozen = g_queue_new ();
1433
1434   worker->write_lock = g_mutex_new ();
1435   worker->write_queue = g_queue_new ();
1436
1437   if (G_IS_SOCKET_CONNECTION (worker->stream))
1438     worker->socket = g_socket_connection_get_socket (G_SOCKET_CONNECTION (worker->stream));
1439
1440   _g_dbus_shared_thread_ref (_g_dbus_worker_thread_begin_func, worker);
1441
1442   return worker;
1443 }
1444
1445 /* ---------------------------------------------------------------------------------------------------- */
1446
1447 /* This can be called from any thread - frees worker. Note that
1448  * callbacks might still happen if called from another thread than the
1449  * worker - use your own synchronization primitive in the callbacks.
1450  */
1451 void
1452 _g_dbus_worker_stop (GDBusWorker *worker)
1453 {
1454   worker->stopped = TRUE;
1455   g_cancellable_cancel (worker->cancellable);
1456   _g_dbus_worker_unref (worker);
1457 }
1458
1459 /* ---------------------------------------------------------------------------------------------------- */
1460
1461 /* can be called from any thread (except the worker thread) - blocks
1462  * calling thread until all queued outgoing messages are written and
1463  * the transport has been flushed
1464  */
1465 gboolean
1466 _g_dbus_worker_flush_sync (GDBusWorker    *worker,
1467                            GCancellable   *cancellable,
1468                            GError        **error)
1469 {
1470   gboolean ret;
1471   FlushData *data;
1472
1473   data = NULL;
1474   ret = TRUE;
1475
1476   /* if the queue is empty, there's nothing to wait for */
1477   g_mutex_lock (worker->write_lock);
1478   if (g_queue_get_length (worker->write_queue) > 0)
1479     {
1480       data = g_new0 (FlushData, 1);
1481       data->mutex = g_mutex_new ();
1482       data->cond = g_cond_new ();
1483       data->number_to_wait_for = worker->write_num_messages_written + g_queue_get_length (worker->write_queue);
1484       g_mutex_lock (data->mutex);
1485       worker->write_pending_flushes = g_list_prepend (worker->write_pending_flushes, data);
1486     }
1487   g_mutex_unlock (worker->write_lock);
1488
1489   if (data != NULL)
1490     {
1491       g_cond_wait (data->cond, data->mutex);
1492       g_mutex_unlock (data->mutex);
1493
1494       /* note:the element is removed from worker->write_pending_flushes in flush_cb() above */
1495       g_cond_free (data->cond);
1496       g_mutex_free (data->mutex);
1497       if (data->error != NULL)
1498         {
1499           ret = FALSE;
1500           g_propagate_error (error, data->error);
1501         }
1502       g_free (data);
1503     }
1504
1505   return ret;
1506 }
1507
1508 /* ---------------------------------------------------------------------------------------------------- */
1509
1510 #define G_DBUS_DEBUG_AUTHENTICATION (1<<0)
1511 #define G_DBUS_DEBUG_TRANSPORT      (1<<1)
1512 #define G_DBUS_DEBUG_MESSAGE        (1<<2)
1513 #define G_DBUS_DEBUG_PAYLOAD        (1<<3)
1514 #define G_DBUS_DEBUG_CALL           (1<<4)
1515 #define G_DBUS_DEBUG_SIGNAL         (1<<5)
1516 #define G_DBUS_DEBUG_INCOMING       (1<<6)
1517 #define G_DBUS_DEBUG_RETURN         (1<<7)
1518 #define G_DBUS_DEBUG_EMISSION       (1<<8)
1519 #define G_DBUS_DEBUG_ADDRESS        (1<<9)
1520
1521 static gint _gdbus_debug_flags = 0;
1522
1523 gboolean
1524 _g_dbus_debug_authentication (void)
1525 {
1526   _g_dbus_initialize ();
1527   return (_gdbus_debug_flags & G_DBUS_DEBUG_AUTHENTICATION) != 0;
1528 }
1529
1530 gboolean
1531 _g_dbus_debug_transport (void)
1532 {
1533   _g_dbus_initialize ();
1534   return (_gdbus_debug_flags & G_DBUS_DEBUG_TRANSPORT) != 0;
1535 }
1536
1537 gboolean
1538 _g_dbus_debug_message (void)
1539 {
1540   _g_dbus_initialize ();
1541   return (_gdbus_debug_flags & G_DBUS_DEBUG_MESSAGE) != 0;
1542 }
1543
1544 gboolean
1545 _g_dbus_debug_payload (void)
1546 {
1547   _g_dbus_initialize ();
1548   return (_gdbus_debug_flags & G_DBUS_DEBUG_PAYLOAD) != 0;
1549 }
1550
1551 gboolean
1552 _g_dbus_debug_call (void)
1553 {
1554   _g_dbus_initialize ();
1555   return (_gdbus_debug_flags & G_DBUS_DEBUG_CALL) != 0;
1556 }
1557
1558 gboolean
1559 _g_dbus_debug_signal (void)
1560 {
1561   _g_dbus_initialize ();
1562   return (_gdbus_debug_flags & G_DBUS_DEBUG_SIGNAL) != 0;
1563 }
1564
1565 gboolean
1566 _g_dbus_debug_incoming (void)
1567 {
1568   _g_dbus_initialize ();
1569   return (_gdbus_debug_flags & G_DBUS_DEBUG_INCOMING) != 0;
1570 }
1571
1572 gboolean
1573 _g_dbus_debug_return (void)
1574 {
1575   _g_dbus_initialize ();
1576   return (_gdbus_debug_flags & G_DBUS_DEBUG_RETURN) != 0;
1577 }
1578
1579 gboolean
1580 _g_dbus_debug_emission (void)
1581 {
1582   _g_dbus_initialize ();
1583   return (_gdbus_debug_flags & G_DBUS_DEBUG_EMISSION) != 0;
1584 }
1585
1586 gboolean
1587 _g_dbus_debug_address (void)
1588 {
1589   _g_dbus_initialize ();
1590   return (_gdbus_debug_flags & G_DBUS_DEBUG_ADDRESS) != 0;
1591 }
1592
1593 G_LOCK_DEFINE_STATIC (print_lock);
1594
1595 void
1596 _g_dbus_debug_print_lock (void)
1597 {
1598   G_LOCK (print_lock);
1599 }
1600
1601 void
1602 _g_dbus_debug_print_unlock (void)
1603 {
1604   G_UNLOCK (print_lock);
1605 }
1606
1607 /*
1608  * _g_dbus_initialize:
1609  *
1610  * Does various one-time init things such as
1611  *
1612  *  - registering the G_DBUS_ERROR error domain
1613  *  - parses the G_DBUS_DEBUG environment variable
1614  */
1615 void
1616 _g_dbus_initialize (void)
1617 {
1618   static volatile gsize initialized = 0;
1619
1620   if (g_once_init_enter (&initialized))
1621     {
1622       volatile GQuark g_dbus_error_domain;
1623       const gchar *debug;
1624
1625       g_dbus_error_domain = G_DBUS_ERROR;
1626
1627       debug = g_getenv ("G_DBUS_DEBUG");
1628       if (debug != NULL)
1629         {
1630           const GDebugKey keys[] = {
1631             { "authentication", G_DBUS_DEBUG_AUTHENTICATION },
1632             { "transport",      G_DBUS_DEBUG_TRANSPORT      },
1633             { "message",        G_DBUS_DEBUG_MESSAGE        },
1634             { "payload",        G_DBUS_DEBUG_PAYLOAD        },
1635             { "call",           G_DBUS_DEBUG_CALL           },
1636             { "signal",         G_DBUS_DEBUG_SIGNAL         },
1637             { "incoming",       G_DBUS_DEBUG_INCOMING       },
1638             { "return",         G_DBUS_DEBUG_RETURN         },
1639             { "emission",       G_DBUS_DEBUG_EMISSION       },
1640             { "address",        G_DBUS_DEBUG_ADDRESS        }
1641           };
1642
1643           _gdbus_debug_flags = g_parse_debug_string (debug, keys, G_N_ELEMENTS (keys));
1644           if (_gdbus_debug_flags & G_DBUS_DEBUG_PAYLOAD)
1645             _gdbus_debug_flags |= G_DBUS_DEBUG_MESSAGE;
1646         }
1647
1648       g_once_init_leave (&initialized, 1);
1649     }
1650 }
1651
1652 /* ---------------------------------------------------------------------------------------------------- */
1653
1654 GVariantType *
1655 _g_dbus_compute_complete_signature (GDBusArgInfo **args)
1656 {
1657   const GVariantType *arg_types[256];
1658   guint n;
1659
1660   if (args)
1661     for (n = 0; args[n] != NULL; n++)
1662       {
1663         /* DBus places a hard limit of 255 on signature length.
1664          * therefore number of args must be less than 256.
1665          */
1666         g_assert (n < 256);
1667
1668         arg_types[n] = G_VARIANT_TYPE (args[n]->signature);
1669
1670         if G_UNLIKELY (arg_types[n] == NULL)
1671           return NULL;
1672       }
1673   else
1674     n = 0;
1675
1676   return g_variant_type_new_tuple (arg_types, n);
1677 }
1678
1679 /* ---------------------------------------------------------------------------------------------------- */
1680
1681 #ifdef G_OS_WIN32
1682
1683 extern BOOL WINAPI ConvertSidToStringSidA (PSID Sid, LPSTR *StringSid);
1684
1685 gchar *
1686 _g_dbus_win32_get_user_sid (void)
1687 {
1688   HANDLE h;
1689   TOKEN_USER *user;
1690   DWORD token_information_len;
1691   PSID psid;
1692   gchar *sid;
1693   gchar *ret;
1694
1695   ret = NULL;
1696   user = NULL;
1697   h = INVALID_HANDLE_VALUE;
1698
1699   if (!OpenProcessToken (GetCurrentProcess (), TOKEN_QUERY, &h))
1700     {
1701       g_warning ("OpenProcessToken failed with error code %d", (gint) GetLastError ());
1702       goto out;
1703     }
1704
1705   /* Get length of buffer */
1706   token_information_len = 0;
1707   if (!GetTokenInformation (h, TokenUser, NULL, 0, &token_information_len))
1708     {
1709       if (GetLastError () != ERROR_INSUFFICIENT_BUFFER)
1710         {
1711           g_warning ("GetTokenInformation() failed with error code %d", (gint) GetLastError ());
1712           goto out;
1713         }
1714     }
1715   user = g_malloc (token_information_len);
1716   if (!GetTokenInformation (h, TokenUser, user, token_information_len, &token_information_len))
1717     {
1718       g_warning ("GetTokenInformation() failed with error code %d", (gint) GetLastError ());
1719       goto out;
1720     }
1721
1722   psid = user->User.Sid;
1723   if (!IsValidSid (psid))
1724     {
1725       g_warning ("Invalid SID");
1726       goto out;
1727     }
1728
1729   if (!ConvertSidToStringSidA (psid, &sid))
1730     {
1731       g_warning ("Invalid SID");
1732       goto out;
1733     }
1734
1735   ret = g_strdup (sid);
1736   LocalFree (sid);
1737
1738 out:
1739   g_free (user);
1740   if (h != INVALID_HANDLE_VALUE)
1741     CloseHandle (h);
1742   return ret;
1743 }
1744 #endif
1745
1746 /* ---------------------------------------------------------------------------------------------------- */
1747
1748 gchar *
1749 _g_dbus_get_machine_id (GError **error)
1750 {
1751   gchar *ret;
1752   /* TODO: use PACKAGE_LOCALSTATEDIR ? */
1753   ret = NULL;
1754   if (!g_file_get_contents ("/var/lib/dbus/machine-id",
1755                             &ret,
1756                             NULL,
1757                             error))
1758     {
1759       g_prefix_error (error, _("Unable to load /var/lib/dbus/machine-id: "));
1760     }
1761   else
1762     {
1763       /* TODO: validate value */
1764       g_strstrip (ret);
1765     }
1766   return ret;
1767 }
1768
1769 /* ---------------------------------------------------------------------------------------------------- */
1770
1771 gchar *
1772 _g_dbus_enum_to_string (GType enum_type, gint value)
1773 {
1774   gchar *ret;
1775   GEnumClass *klass;
1776   GEnumValue *enum_value;
1777
1778   klass = g_type_class_ref (enum_type);
1779   enum_value = g_enum_get_value (klass, value);
1780   if (enum_value != NULL)
1781     ret = g_strdup (enum_value->value_nick);
1782   else
1783     ret = g_strdup_printf ("unknown (value %d)", value);
1784   g_type_class_unref (klass);
1785   return ret;
1786 }
1787
1788 /* ---------------------------------------------------------------------------------------------------- */
1789
1790 static void
1791 write_message_print_transport_debug (gssize bytes_written,
1792                                      MessageToWriteData *data)
1793 {
1794   if (G_LIKELY (!_g_dbus_debug_transport ()))
1795     goto out;
1796
1797   _g_dbus_debug_print_lock ();
1798   g_print ("========================================================================\n"
1799            "GDBus-debug:Transport:\n"
1800            "  >>>> WROTE %" G_GSIZE_FORMAT " bytes of message with serial %d and\n"
1801            "       size %" G_GSIZE_FORMAT " from offset %" G_GSIZE_FORMAT " on a %s\n",
1802            bytes_written,
1803            g_dbus_message_get_serial (data->message),
1804            data->blob_size,
1805            data->total_written,
1806            g_type_name (G_TYPE_FROM_INSTANCE (g_io_stream_get_output_stream (data->worker->stream))));
1807   _g_dbus_debug_print_unlock ();
1808  out:
1809   ;
1810 }
1811
1812 /* ---------------------------------------------------------------------------------------------------- */
1813
1814 static void
1815 read_message_print_transport_debug (gssize bytes_read,
1816                                     GDBusWorker *worker)
1817 {
1818   gsize size;
1819   gint32 serial;
1820   gint32 message_length;
1821
1822   if (G_LIKELY (!_g_dbus_debug_transport ()))
1823     goto out;
1824
1825   size = bytes_read + worker->read_buffer_cur_size;
1826   serial = 0;
1827   message_length = 0;
1828   if (size >= 16)
1829     message_length = g_dbus_message_bytes_needed ((guchar *) worker->read_buffer, size, NULL);
1830   if (size >= 1)
1831     {
1832       switch (worker->read_buffer[0])
1833         {
1834         case 'l':
1835           if (size >= 12)
1836             serial = GUINT32_FROM_LE (((guint32 *) worker->read_buffer)[2]);
1837           break;
1838         case 'B':
1839           if (size >= 12)
1840             serial = GUINT32_FROM_BE (((guint32 *) worker->read_buffer)[2]);
1841           break;
1842         default:
1843           /* an error will be set elsewhere if this happens */
1844           goto out;
1845         }
1846     }
1847
1848     _g_dbus_debug_print_lock ();
1849   g_print ("========================================================================\n"
1850            "GDBus-debug:Transport:\n"
1851            "  <<<< READ %" G_GSIZE_FORMAT " bytes of message with serial %d and\n"
1852            "       size %d to offset %" G_GSIZE_FORMAT " from a %s\n",
1853            bytes_read,
1854            serial,
1855            message_length,
1856            worker->read_buffer_cur_size,
1857            g_type_name (G_TYPE_FROM_INSTANCE (g_io_stream_get_input_stream (worker->stream))));
1858   _g_dbus_debug_print_unlock ();
1859  out:
1860   ;
1861 }