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 static gboolean _g_dbus_worker_do_initial_read (gpointer data);
  59
  60 /* ---------------------------------------------------------------------------------------------------- */
  61
  62 gchar *
  63 _g_dbus_hexdump (const gchar *data, gsize len, guint indent)
  64 {
  65  guint n, m;
  66  GString *ret;
  67
  68  ret = g_string_new (NULL);
  69
  70  for (n = 0; n < len; n += 16)
  71    {
  72      g_string_append_printf (ret, "%*s%04x: ", indent, "", n);
  73
  74      for (m = n; m < n + 16; m++)
  75        {
  76          if (m > n && (m%4) == 0)
  77            g_string_append_c (ret, ' ');
  78          if (m < len)
  79            g_string_append_printf (ret, "%02x ", (guchar) data[m]);
  80          else
  81            g_string_append (ret, "   ");
  82        }
  83
  84      g_string_append (ret, "   ");
  85
  86      for (m = n; m < len && m < n + 16; m++)
  87        g_string_append_c (ret, g_ascii_isprint (data[m]) ? data[m] : '.');
  88
  89      g_string_append_c (ret, '\n');
  90    }
  91
  92  return g_string_free (ret, FALSE);
  93 }
  94
  95 /* ---------------------------------------------------------------------------------------------------- */
  96
  97 /* Unfortunately ancillary messages are discarded when reading from a
  98  * socket using the GSocketInputStream abstraction. So we provide a
  99  * very GInputStream-ish API that uses GSocket in this case (very
 100  * similar to GSocketInputStream).
 101  */
 102
 103 typedef struct
 104 {
 105   GSocket *socket;
 106   GCancellable *cancellable;
 107
 108   void *buffer;
 109   gsize count;
 110
 111   GSocketControlMessage ***messages;
 112   gint *num_messages;
 113
 114   GSimpleAsyncResult *simple;
 115
 116   gboolean from_mainloop;
 117 } ReadWithControlData;
 118
 119 static void
 120 read_with_control_data_free (ReadWithControlData *data)
 121 {
 122   g_object_unref (data->socket);
 123   if (data->cancellable != NULL)
 124     g_object_unref (data->cancellable);
 125   g_object_unref (data->simple);
 126   g_free (data);
 127 }
 128
 129 static gboolean
 130 _g_socket_read_with_control_messages_ready (GSocket      *socket,
 131                                             GIOCondition  condition,
 132                                             gpointer      user_data)
 133 {
 134   ReadWithControlData *data = user_data;
 135   GError *error;
 136   gssize result;
 137   GInputVector vector;
 138
 139   error = NULL;
 140   vector.buffer = data->buffer;
 141   vector.size = data->count;
 142   result = g_socket_receive_message (data->socket,
 143                                      NULL, /* address */
 144                                      &vector,
 145                                      1,
 146                                      data->messages,
 147                                      data->num_messages,
 148                                      NULL,
 149                                      data->cancellable,
 150                                      &error);
 151   if (result >= 0)
 152     {
 153       g_simple_async_result_set_op_res_gssize (data->simple, result);
 154     }
 155   else
 156     {
 157       g_assert (error != NULL);
 158       g_simple_async_result_take_error (data->simple, error);
 159     }
 160
 161   if (data->from_mainloop)
 162     g_simple_async_result_complete (data->simple);
 163   else
 164     g_simple_async_result_complete_in_idle (data->simple);
 165
 166   return FALSE;
 167 }
 168
 169 static void
 170 _g_socket_read_with_control_messages (GSocket                 *socket,
 171                                       void                    *buffer,
 172                                       gsize                    count,
 173                                       GSocketControlMessage ***messages,
 174                                       gint                    *num_messages,
 175                                       gint                     io_priority,
 176                                       GCancellable            *cancellable,
 177                                       GAsyncReadyCallback      callback,
 178                                       gpointer                 user_data)
 179 {
 180   ReadWithControlData *data;
 181
 182   data = g_new0 (ReadWithControlData, 1);
 183   data->socket = g_object_ref (socket);
 184   data->cancellable = cancellable != NULL ? g_object_ref (cancellable) : NULL;
 185   data->buffer = buffer;
 186   data->count = count;
 187   data->messages = messages;
 188   data->num_messages = num_messages;
 189
 190   data->simple = g_simple_async_result_new (G_OBJECT (socket),
 191                                             callback,
 192                                             user_data,
 193                                             _g_socket_read_with_control_messages);
 194   g_simple_async_result_set_check_cancellable (data->simple, cancellable);
 195
 196   if (!g_socket_condition_check (socket, G_IO_IN))
 197     {
 198       GSource *source;
 199       data->from_mainloop = TRUE;
 200       source = g_socket_create_source (data->socket,
 201                                        G_IO_IN | G_IO_HUP | G_IO_ERR,
 202                                        cancellable);
 203       g_source_set_callback (source,
 204                              (GSourceFunc) _g_socket_read_with_control_messages_ready,
 205                              data,
 206                              (GDestroyNotify) read_with_control_data_free);
 207       g_source_attach (source, g_main_context_get_thread_default ());
 208       g_source_unref (source);
 209     }
 210   else
 211     {
 212       _g_socket_read_with_control_messages_ready (data->socket, G_IO_IN, data);
 213       read_with_control_data_free (data);
 214     }
 215 }
 216
 217 static gssize
 218 _g_socket_read_with_control_messages_finish (GSocket       *socket,
 219                                              GAsyncResult  *result,
 220                                              GError       **error)
 221 {
 222   GSimpleAsyncResult *simple = G_SIMPLE_ASYNC_RESULT (result);
 223
 224   g_return_val_if_fail (G_IS_SOCKET (socket), -1);
 225   g_warn_if_fail (g_simple_async_result_get_source_tag (simple) == _g_socket_read_with_control_messages);
 226
 227   if (g_simple_async_result_propagate_error (simple, error))
 228       return -1;
 229   else
 230     return g_simple_async_result_get_op_res_gssize (simple);
 231 }
 232
 233 /* ---------------------------------------------------------------------------------------------------- */
 234
 235 /* Work-around for https://bugzilla.gnome.org/show_bug.cgi?id=627724 */
 236
 237 static GPtrArray *ensured_classes = NULL;
 238
 239 static void
 240 ensure_type (GType gtype)
 241 {
 242   g_ptr_array_add (ensured_classes, g_type_class_ref (gtype));
 243 }
 244
 245 static void
 246 release_required_types (void)
 247 {
 248   g_ptr_array_foreach (ensured_classes, (GFunc) g_type_class_unref, NULL);
 249   g_ptr_array_unref (ensured_classes);
 250   ensured_classes = NULL;
 251 }
 252
 253 static void
 254 ensure_required_types (void)
 255 {
 256   g_assert (ensured_classes == NULL);
 257   ensured_classes = g_ptr_array_new ();
 258   ensure_type (G_TYPE_SIMPLE_ASYNC_RESULT);
 259   ensure_type (G_TYPE_MEMORY_INPUT_STREAM);
 260 }
 261 /* ---------------------------------------------------------------------------------------------------- */
 262
 263 typedef struct
 264 {
 265   volatile gint refcount;
 266   GThread *thread;
 267   GMainContext *context;
 268   GMainLoop *loop;
 269 } SharedThreadData;
 270
 271 static gpointer
 272 gdbus_shared_thread_func (gpointer user_data)
 273 {
 274   SharedThreadData *data = user_data;
 275
 276   g_main_context_push_thread_default (data->context);
 277   g_main_loop_run (data->loop);
 278   g_main_context_pop_thread_default (data->context);
 279
 280   release_required_types ();
 281
 282   return NULL;
 283 }
 284
 285 /* ---------------------------------------------------------------------------------------------------- */
 286
 287 static SharedThreadData *
 288 _g_dbus_shared_thread_ref (void)
 289 {
 290   static gsize shared_thread_data = 0;
 291   SharedThreadData *ret;
 292
 293   if (g_once_init_enter (&shared_thread_data))
 294     {
 295       SharedThreadData *data;
 296
 297       /* Work-around for https://bugzilla.gnome.org/show_bug.cgi?id=627724 */
 298       ensure_required_types ();
 299
 300       data = g_new0 (SharedThreadData, 1);
 301       data->refcount = 0;
 302
 303       data->context = g_main_context_new ();
 304       data->loop = g_main_loop_new (data->context, FALSE);
 305       data->thread = g_thread_new ("gdbus",
 306                                    gdbus_shared_thread_func,
 307                                    data);
 308       /* We can cast between gsize and gpointer safely */
 309       g_once_init_leave (&shared_thread_data, (gsize) data);
 310     }
 311
 312   ret = (SharedThreadData*) shared_thread_data;
 313   g_atomic_int_inc (&ret->refcount);
 314   return ret;
 315 }
 316
 317 static void
 318 _g_dbus_shared_thread_unref (SharedThreadData *data)
 319 {
 320   /* TODO: actually destroy the shared thread here */
 321 #if 0
 322   g_assert (data != NULL);
 323   if (g_atomic_int_dec_and_test (&data->refcount))
 324     {
 325       g_main_loop_quit (data->loop);
 326       //g_thread_join (data->thread);
 327       g_main_loop_unref (data->loop);
 328       g_main_context_unref (data->context);
 329     }
 330 #endif
 331 }
 332
 333 /* ---------------------------------------------------------------------------------------------------- */
 334
 335 typedef enum {
 336     PENDING_NONE = 0,
 337     PENDING_WRITE,
 338     PENDING_FLUSH,
 339     PENDING_CLOSE
 340 } OutputPending;
 341
 342 struct GDBusWorker
 343 {
 344   volatile gint                       ref_count;
 345
 346   SharedThreadData                   *shared_thread_data;
 347
 348   /* really a boolean, but GLib 2.28 lacks atomic boolean ops */
 349   volatile gint                       stopped;
 350
 351   /* TODO: frozen (e.g. G_DBUS_CONNECTION_FLAGS_DELAY_MESSAGE_PROCESSING) currently
 352    * only affects messages received from the other peer (since GDBusServer is the
 353    * only user) - we might want it to affect messages sent to the other peer too?
 354    */
 355   gboolean                            frozen;
 356   GDBusCapabilityFlags                capabilities;
 357   GQueue                             *received_messages_while_frozen;
 358
 359   GIOStream                          *stream;
 360   GCancellable                       *cancellable;
 361   GDBusWorkerMessageReceivedCallback  message_received_callback;
 362   GDBusWorkerMessageAboutToBeSentCallback message_about_to_be_sent_callback;
 363   GDBusWorkerDisconnectedCallback     disconnected_callback;
 364   gpointer                            user_data;
 365
 366   /* if not NULL, stream is GSocketConnection */
 367   GSocket *socket;
 368
 369   /* used for reading */
 370   GMutex                              read_lock;
 371   gchar                              *read_buffer;
 372   gsize                               read_buffer_allocated_size;
 373   gsize                               read_buffer_cur_size;
 374   gsize                               read_buffer_bytes_wanted;
 375   GUnixFDList                        *read_fd_list;
 376   GSocketControlMessage             **read_ancillary_messages;
 377   gint                                read_num_ancillary_messages;
 378
 379   /* Whether an async write, flush or close, or none of those, is pending.
 380    * Only the worker thread may change its value, and only with the write_lock.
 381    * Other threads may read its value when holding the write_lock.
 382    * The worker thread may read its value at any time.
 383    */
 384   OutputPending                       output_pending;
 385   /* used for writing */
 386   GMutex                              write_lock;
 387   /* queue of MessageToWriteData, protected by write_lock */
 388   GQueue                             *write_queue;
 389   /* protected by write_lock */
 390   guint64                             write_num_messages_written;
 391   /* number of messages we'd written out last time we flushed;
 392    * protected by write_lock
 393    */
 394   guint64                             write_num_messages_flushed;
 395   /* list of FlushData, protected by write_lock */
 396   GList                              *write_pending_flushes;
 397   /* list of CloseData, protected by write_lock */
 398   GList                              *pending_close_attempts;
 399   /* no lock - only used from the worker thread */
 400   gboolean                            close_expected;
 401 };
 402
 403 static void _g_dbus_worker_unref (GDBusWorker *worker);
 404
 405 /* ---------------------------------------------------------------------------------------------------- */
 406
 407 typedef struct
 408 {
 409   GMutex  mutex;
 410   GCond   cond;
 411   guint64 number_to_wait_for;
 412   GError *error;
 413 } FlushData;
 414
 415 struct _MessageToWriteData ;
 416 typedef struct _MessageToWriteData MessageToWriteData;
 417
 418 static void message_to_write_data_free (MessageToWriteData *data);
 419
 420 static void read_message_print_transport_debug (gssize bytes_read,
 421                                                 GDBusWorker *worker);
 422
 423 static void write_message_print_transport_debug (gssize bytes_written,
 424                                                  MessageToWriteData *data);
 425
 426 typedef struct {
 427     GDBusWorker *worker;
 428     GCancellable *cancellable;
 429     GSimpleAsyncResult *result;
 430 } CloseData;
 431
 432 static void close_data_free (CloseData *close_data)
 433 {
 434   if (close_data->cancellable != NULL)
 435     g_object_unref (close_data->cancellable);
 436
 437   if (close_data->result != NULL)
 438     g_object_unref (close_data->result);
 439
 440   _g_dbus_worker_unref (close_data->worker);
 441   g_slice_free (CloseData, close_data);
 442 }
 443
 444 /* ---------------------------------------------------------------------------------------------------- */
 445
 446 static GDBusWorker *
 447 _g_dbus_worker_ref (GDBusWorker *worker)
 448 {
 449   g_atomic_int_inc (&worker->ref_count);
 450   return worker;
 451 }
 452
 453 static void
 454 _g_dbus_worker_unref (GDBusWorker *worker)
 455 {
 456   if (g_atomic_int_dec_and_test (&worker->ref_count))
 457     {
 458       g_assert (worker->write_pending_flushes == NULL);
 459
 460       _g_dbus_shared_thread_unref (worker->shared_thread_data);
 461
 462       g_object_unref (worker->stream);
 463
 464       g_mutex_clear (&worker->read_lock);
 465       g_object_unref (worker->cancellable);
 466       if (worker->read_fd_list != NULL)
 467         g_object_unref (worker->read_fd_list);
 468
 469       g_queue_free_full (worker->received_messages_while_frozen, (GDestroyNotify) g_object_unref);
 470       g_mutex_clear (&worker->write_lock);
 471       g_queue_free_full (worker->write_queue, (GDestroyNotify) message_to_write_data_free);
 472       g_free (worker->read_buffer);
 473
 474       g_free (worker);
 475     }
 476 }
 477
 478 static void
 479 _g_dbus_worker_emit_disconnected (GDBusWorker  *worker,
 480                                   gboolean      remote_peer_vanished,
 481                                   GError       *error)
 482 {
 483   if (!g_atomic_int_get (&worker->stopped))
 484     worker->disconnected_callback (worker, remote_peer_vanished, error, worker->user_data);
 485 }
 486
 487 static void
 488 _g_dbus_worker_emit_message_received (GDBusWorker  *worker,
 489                                       GDBusMessage *message)
 490 {
 491   if (!g_atomic_int_get (&worker->stopped))
 492     worker->message_received_callback (worker, message, worker->user_data);
 493 }
 494
 495 static GDBusMessage *
 496 _g_dbus_worker_emit_message_about_to_be_sent (GDBusWorker  *worker,
 497                                               GDBusMessage *message)
 498 {
 499   GDBusMessage *ret;
 500   if (!g_atomic_int_get (&worker->stopped))
 501     ret = worker->message_about_to_be_sent_callback (worker, message, worker->user_data);
 502   else
 503     ret = message;
 504   return ret;
 505 }
 506
 507 /* can only be called from private thread with read-lock held - takes ownership of @message */
 508 static void
 509 _g_dbus_worker_queue_or_deliver_received_message (GDBusWorker  *worker,
 510                                                   GDBusMessage *message)
 511 {
 512   if (worker->frozen || g_queue_get_length (worker->received_messages_while_frozen) > 0)
 513     {
 514       /* queue up */
 515       g_queue_push_tail (worker->received_messages_while_frozen, message);
 516     }
 517   else
 518     {
 519       /* not frozen, nor anything in queue */
 520       _g_dbus_worker_emit_message_received (worker, message);
 521       g_object_unref (message);
 522     }
 523 }
 524
 525 /* called in private thread shared by all GDBusConnection instances (without read-lock held) */
 526 static gboolean
 527 unfreeze_in_idle_cb (gpointer user_data)
 528 {
 529   GDBusWorker *worker = user_data;
 530   GDBusMessage *message;
 531
 532   g_mutex_lock (&worker->read_lock);
 533   if (worker->frozen)
 534     {
 535       while ((message = g_queue_pop_head (worker->received_messages_while_frozen)) != NULL)
 536         {
 537           _g_dbus_worker_emit_message_received (worker, message);
 538           g_object_unref (message);
 539         }
 540       worker->frozen = FALSE;
 541     }
 542   else
 543     {
 544       g_assert (g_queue_get_length (worker->received_messages_while_frozen) == 0);
 545     }
 546   g_mutex_unlock (&worker->read_lock);
 547   return FALSE;
 548 }
 549
 550 /* can be called from any thread */
 551 void
 552 _g_dbus_worker_unfreeze (GDBusWorker *worker)
 553 {
 554   GSource *idle_source;
 555   idle_source = g_idle_source_new ();
 556   g_source_set_priority (idle_source, G_PRIORITY_DEFAULT);
 557   g_source_set_callback (idle_source,
 558                          unfreeze_in_idle_cb,
 559                          _g_dbus_worker_ref (worker),
 560                          (GDestroyNotify) _g_dbus_worker_unref);
 561   g_source_attach (idle_source, worker->shared_thread_data->context);
 562   g_source_unref (idle_source);
 563 }
 564
 565 /* ---------------------------------------------------------------------------------------------------- */
 566
 567 static void _g_dbus_worker_do_read_unlocked (GDBusWorker *worker);
 568
 569 /* called in private thread shared by all GDBusConnection instances (without read-lock held) */
 570 static void
 571 _g_dbus_worker_do_read_cb (GInputStream  *input_stream,
 572                            GAsyncResult  *res,
 573                            gpointer       user_data)
 574 {
 575   GDBusWorker *worker = user_data;
 576   GError *error;
 577   gssize bytes_read;
 578
 579   g_mutex_lock (&worker->read_lock);
 580
 581   /* If already stopped, don't even process the reply */
 582   if (g_atomic_int_get (&worker->stopped))
 583     goto out;
 584
 585   error = NULL;
 586   if (worker->socket == NULL)
 587     bytes_read = g_input_stream_read_finish (g_io_stream_get_input_stream (worker->stream),
 588                                              res,
 589                                              &error);
 590   else
 591     bytes_read = _g_socket_read_with_control_messages_finish (worker->socket,
 592                                                               res,
 593                                                               &error);
 594   if (worker->read_num_ancillary_messages > 0)
 595     {
 596       gint n;
 597       for (n = 0; n < worker->read_num_ancillary_messages; n++)
 598         {
 599           GSocketControlMessage *control_message = G_SOCKET_CONTROL_MESSAGE (worker->read_ancillary_messages[n]);
 600
 601           if (FALSE)
 602             {
 603             }
 604 #ifdef G_OS_UNIX
 605           else if (G_IS_UNIX_FD_MESSAGE (control_message))
 606             {
 607               GUnixFDMessage *fd_message;
 608               gint *fds;
 609               gint num_fds;
 610
 611               fd_message = G_UNIX_FD_MESSAGE (control_message);
 612               fds = g_unix_fd_message_steal_fds (fd_message, &num_fds);
 613               if (worker->read_fd_list == NULL)
 614                 {
 615                   worker->read_fd_list = g_unix_fd_list_new_from_array (fds, num_fds);
 616                 }
 617               else
 618                 {
 619                   gint n;
 620                   for (n = 0; n < num_fds; n++)
 621                     {
 622                       /* TODO: really want a append_steal() */
 623                       g_unix_fd_list_append (worker->read_fd_list, fds[n], NULL);
 624                       close (fds[n]);
 625                     }
 626                 }
 627               g_free (fds);
 628             }
 629           else if (G_IS_UNIX_CREDENTIALS_MESSAGE (control_message))
 630             {
 631               /* do nothing */
 632             }
 633 #endif
 634           else
 635             {
 636               if (error == NULL)
 637                 {
 638                   g_set_error (&error,
 639                                G_IO_ERROR,
 640                                G_IO_ERROR_FAILED,
 641                                "Unexpected ancillary message of type %s received from peer",
 642                                g_type_name (G_TYPE_FROM_INSTANCE (control_message)));
 643                   _g_dbus_worker_emit_disconnected (worker, TRUE, error);
 644                   g_error_free (error);
 645                   g_object_unref (control_message);
 646                   n++;
 647                   while (n < worker->read_num_ancillary_messages)
 648                     g_object_unref (worker->read_ancillary_messages[n++]);
 649                   g_free (worker->read_ancillary_messages);
 650                   goto out;
 651                 }
 652             }
 653           g_object_unref (control_message);
 654         }
 655       g_free (worker->read_ancillary_messages);
 656     }
 657
 658   if (bytes_read == -1)
 659     {
 660       if (G_UNLIKELY (_g_dbus_debug_transport ()))
 661         {
 662           _g_dbus_debug_print_lock ();
 663           g_print ("========================================================================\n"
 664                    "GDBus-debug:Transport:\n"
 665                    "  ---- READ ERROR on stream of type %s:\n"
 666                    "  ---- %s %d: %s\n",
 667                    g_type_name (G_TYPE_FROM_INSTANCE (g_io_stream_get_input_stream (worker->stream))),
 668                    g_quark_to_string (error->domain), error->code,
 669                    error->message);
 670           _g_dbus_debug_print_unlock ();
 671         }
 672
 673       /* Every async read that uses this callback uses worker->cancellable
 674        * as its GCancellable. worker->cancellable gets cancelled if and only
 675        * if the GDBusConnection tells us to close (either via
 676        * _g_dbus_worker_stop, which is called on last-unref, or directly),
 677        * so a cancelled read must mean our connection was closed locally.
 678        *
 679        * If we're closing, other errors are possible - notably,
 680        * G_IO_ERROR_CLOSED can be seen if we close the stream with an async
 681        * read in-flight. It seems sensible to treat all read errors during
 682        * closing as an expected thing that doesn't trip exit-on-close.
 683        *
 684        * Because close_expected can't be set until we get into the worker
 685        * thread, but the cancellable is signalled sooner (from another
 686        * thread), we do still need to check the error.
 687        */
 688       if (worker->close_expected ||
 689           g_error_matches (error, G_IO_ERROR, G_IO_ERROR_CANCELLED))
 690         _g_dbus_worker_emit_disconnected (worker, FALSE, NULL);
 691       else
 692         _g_dbus_worker_emit_disconnected (worker, TRUE, error);
 693
 694       g_error_free (error);
 695       goto out;
 696     }
 697
 698 #if 0
 699   g_debug ("read %d bytes (is_closed=%d blocking=%d condition=0x%02x) stream %p, %p",
 700            (gint) bytes_read,
 701            g_socket_is_closed (g_socket_connection_get_socket (G_SOCKET_CONNECTION (worker->stream))),
 702            g_socket_get_blocking (g_socket_connection_get_socket (G_SOCKET_CONNECTION (worker->stream))),
 703            g_socket_condition_check (g_socket_connection_get_socket (G_SOCKET_CONNECTION (worker->stream)),
 704                                      G_IO_IN | G_IO_OUT | G_IO_HUP),
 705            worker->stream,
 706            worker);
 707 #endif
 708
 709   /* TODO: hmm, hmm... */
 710   if (bytes_read == 0)
 711     {
 712       g_set_error (&error,
 713                    G_IO_ERROR,
 714                    G_IO_ERROR_FAILED,
 715                    "Underlying GIOStream returned 0 bytes on an async read");
 716       _g_dbus_worker_emit_disconnected (worker, TRUE, error);
 717       g_error_free (error);
 718       goto out;
 719     }
 720
 721   read_message_print_transport_debug (bytes_read, worker);
 722
 723   worker->read_buffer_cur_size += bytes_read;
 724   if (worker->read_buffer_bytes_wanted == worker->read_buffer_cur_size)
 725     {
 726       /* OK, got what we asked for! */
 727       if (worker->read_buffer_bytes_wanted == 16)
 728         {
 729           gssize message_len;
 730           /* OK, got the header - determine how many more bytes are needed */
 731           error = NULL;
 732           message_len = g_dbus_message_bytes_needed ((guchar *) worker->read_buffer,
 733                                                      16,
 734                                                      &error);
 735           if (message_len == -1)
 736             {
 737               g_warning ("_g_dbus_worker_do_read_cb: error determing bytes needed: %s", error->message);
 738               _g_dbus_worker_emit_disconnected (worker, FALSE, error);
 739               g_error_free (error);
 740               goto out;
 741             }
 742
 743           worker->read_buffer_bytes_wanted = message_len;
 744           _g_dbus_worker_do_read_unlocked (worker);
 745         }
 746       else
 747         {
 748           GDBusMessage *message;
 749           error = NULL;
 750
 751           /* TODO: use connection->priv->auth to decode the message */
 752
 753           message = g_dbus_message_new_from_blob ((guchar *) worker->read_buffer,
 754                                                   worker->read_buffer_cur_size,
 755                                                   worker->capabilities,
 756                                                   &error);
 757           if (message == NULL)
 758             {
 759               gchar *s;
 760               s = _g_dbus_hexdump (worker->read_buffer, worker->read_buffer_cur_size, 2);
 761               g_warning ("Error decoding D-Bus message of %" G_GSIZE_FORMAT " bytes\n"
 762                          "The error is: %s\n"
 763                          "The payload is as follows:\n"
 764                          "%s\n",
 765                          worker->read_buffer_cur_size,
 766                          error->message,
 767                          s);
 768               g_free (s);
 769               _g_dbus_worker_emit_disconnected (worker, FALSE, error);
 770               g_error_free (error);
 771               goto out;
 772             }
 773
 774 #ifdef G_OS_UNIX
 775           if (worker->read_fd_list != NULL)
 776             {
 777               g_dbus_message_set_unix_fd_list (message, worker->read_fd_list);
 778               g_object_unref (worker->read_fd_list);
 779               worker->read_fd_list = NULL;
 780             }
 781 #endif
 782
 783           if (G_UNLIKELY (_g_dbus_debug_message ()))
 784             {
 785               gchar *s;
 786               _g_dbus_debug_print_lock ();
 787               g_print ("========================================================================\n"
 788                        "GDBus-debug:Message:\n"
 789                        "  <<<< RECEIVED D-Bus message (%" G_GSIZE_FORMAT " bytes)\n",
 790                        worker->read_buffer_cur_size);
 791               s = g_dbus_message_print (message, 2);
 792               g_print ("%s", s);
 793               g_free (s);
 794               if (G_UNLIKELY (_g_dbus_debug_payload ()))
 795                 {
 796                   s = _g_dbus_hexdump (worker->read_buffer, worker->read_buffer_cur_size, 2);
 797                   g_print ("%s\n", s);
 798                   g_free (s);
 799                 }
 800               _g_dbus_debug_print_unlock ();
 801             }
 802
 803           /* yay, got a message, go deliver it */
 804           _g_dbus_worker_queue_or_deliver_received_message (worker, message);
 805
 806           /* start reading another message! */
 807           worker->read_buffer_bytes_wanted = 0;
 808           worker->read_buffer_cur_size = 0;
 809           _g_dbus_worker_do_read_unlocked (worker);
 810         }
 811     }
 812   else
 813     {
 814       /* didn't get all the bytes we requested - so repeat the request... */
 815       _g_dbus_worker_do_read_unlocked (worker);
 816     }
 817
 818  out:
 819   g_mutex_unlock (&worker->read_lock);
 820
 821   /* gives up the reference acquired when calling g_input_stream_read_async() */
 822   _g_dbus_worker_unref (worker);
 823 }
 824
 825 /* called in private thread shared by all GDBusConnection instances (with read-lock held) */
 826 static void
 827 _g_dbus_worker_do_read_unlocked (GDBusWorker *worker)
 828 {
 829   /* Note that we do need to keep trying to read even if close_expected is
 830    * true, because only failing a read causes us to signal 'closed'.
 831    */
 832
 833   /* if bytes_wanted is zero, it means start reading a message */
 834   if (worker->read_buffer_bytes_wanted == 0)
 835     {
 836       worker->read_buffer_cur_size = 0;
 837       worker->read_buffer_bytes_wanted = 16;
 838     }
 839
 840   /* ensure we have a (big enough) buffer */
 841   if (worker->read_buffer == NULL || worker->read_buffer_bytes_wanted > worker->read_buffer_allocated_size)
 842     {
 843       /* TODO: 4096 is randomly chosen; might want a better chosen default minimum */
 844       worker->read_buffer_allocated_size = MAX (worker->read_buffer_bytes_wanted, 4096);
 845       worker->read_buffer = g_realloc (worker->read_buffer, worker->read_buffer_allocated_size);
 846     }
 847
 848   if (worker->socket == NULL)
 849     g_input_stream_read_async (g_io_stream_get_input_stream (worker->stream),
 850                                worker->read_buffer + worker->read_buffer_cur_size,
 851                                worker->read_buffer_bytes_wanted - worker->read_buffer_cur_size,
 852                                G_PRIORITY_DEFAULT,
 853                                worker->cancellable,
 854                                (GAsyncReadyCallback) _g_dbus_worker_do_read_cb,
 855                                _g_dbus_worker_ref (worker));
 856   else
 857     {
 858       worker->read_ancillary_messages = NULL;
 859       worker->read_num_ancillary_messages = 0;
 860       _g_socket_read_with_control_messages (worker->socket,
 861                                             worker->read_buffer + worker->read_buffer_cur_size,
 862                                             worker->read_buffer_bytes_wanted - worker->read_buffer_cur_size,
 863                                             &worker->read_ancillary_messages,
 864                                             &worker->read_num_ancillary_messages,
 865                                             G_PRIORITY_DEFAULT,
 866                                             worker->cancellable,
 867                                             (GAsyncReadyCallback) _g_dbus_worker_do_read_cb,
 868                                             _g_dbus_worker_ref (worker));
 869     }
 870 }
 871
 872 /* called in private thread shared by all GDBusConnection instances (without read-lock held) */
 873 static gboolean
 874 _g_dbus_worker_do_initial_read (gpointer data)
 875 {
 876   GDBusWorker *worker = data;
 877   g_mutex_lock (&worker->read_lock);
 878   _g_dbus_worker_do_read_unlocked (worker);
 879   g_mutex_unlock (&worker->read_lock);
 880   return FALSE;
 881 }
 882
 883 /* ---------------------------------------------------------------------------------------------------- */
 884
 885 struct _MessageToWriteData
 886 {
 887   GDBusWorker  *worker;
 888   GDBusMessage *message;
 889   gchar        *blob;
 890   gsize         blob_size;
 891
 892   gsize               total_written;
 893   GSimpleAsyncResult *simple;
 894
 895 };
 896
 897 static void
 898 message_to_write_data_free (MessageToWriteData *data)
 899 {
 900   _g_dbus_worker_unref (data->worker);
 901   if (data->message)
 902     g_object_unref (data->message);
 903   g_free (data->blob);
 904   g_free (data);
 905 }
 906
 907 /* ---------------------------------------------------------------------------------------------------- */
 908
 909 static void write_message_continue_writing (MessageToWriteData *data);
 910
 911 /* called in private thread shared by all GDBusConnection instances
 912  *
 913  * write-lock is not held on entry
 914  * output_pending is PENDING_WRITE on entry
 915  */
 916 static void
 917 write_message_async_cb (GObject      *source_object,
 918                         GAsyncResult *res,
 919                         gpointer      user_data)
 920 {
 921   MessageToWriteData *data = user_data;
 922   GSimpleAsyncResult *simple;
 923   gssize bytes_written;
 924   GError *error;
 925
 926   /* Note: we can't access data->simple after calling g_async_result_complete () because the
 927    * callback can free @data and we're not completing in idle. So use a copy of the pointer.
 928    */
 929   simple = data->simple;
 930
 931   error = NULL;
 932   bytes_written = g_output_stream_write_finish (G_OUTPUT_STREAM (source_object),
 933                                                 res,
 934                                                 &error);
 935   if (bytes_written == -1)
 936     {
 937       g_simple_async_result_take_error (simple, error);
 938       g_simple_async_result_complete (simple);
 939       g_object_unref (simple);
 940       goto out;
 941     }
 942   g_assert (bytes_written > 0); /* zero is never returned */
 943
 944   write_message_print_transport_debug (bytes_written, data);
 945
 946   data->total_written += bytes_written;
 947   g_assert (data->total_written <= data->blob_size);
 948   if (data->total_written == data->blob_size)
 949     {
 950       g_simple_async_result_complete (simple);
 951       g_object_unref (simple);
 952       goto out;
 953     }
 954
 955   write_message_continue_writing (data);
 956
 957  out:
 958   ;
 959 }
 960
 961 /* called in private thread shared by all GDBusConnection instances
 962  *
 963  * write-lock is not held on entry
 964  * output_pending is PENDING_WRITE on entry
 965  */
 966 static gboolean
 967 on_socket_ready (GSocket      *socket,
 968                  GIOCondition  condition,
 969                  gpointer      user_data)
 970 {
 971   MessageToWriteData *data = user_data;
 972   write_message_continue_writing (data);
 973   return FALSE; /* remove source */
 974 }
 975
 976 /* called in private thread shared by all GDBusConnection instances
 977  *
 978  * write-lock is not held on entry
 979  * output_pending is PENDING_WRITE on entry
 980  */
 981 static void
 982 write_message_continue_writing (MessageToWriteData *data)
 983 {
 984   GOutputStream *ostream;
 985   GSimpleAsyncResult *simple;
 986 #ifdef G_OS_UNIX
 987   GUnixFDList *fd_list;
 988 #endif
 989
 990   /* Note: we can't access data->simple after calling g_async_result_complete () because the
 991    * callback can free @data and we're not completing in idle. So use a copy of the pointer.
 992    */
 993   simple = data->simple;
 994
 995   ostream = g_io_stream_get_output_stream (data->worker->stream);
 996 #ifdef G_OS_UNIX
 997   fd_list = g_dbus_message_get_unix_fd_list (data->message);
 998 #endif
 999
1000   g_assert (!g_output_stream_has_pending (ostream));
1001   g_assert_cmpint (data->total_written, <, data->blob_size);
1002
1003   if (FALSE)
1004     {
1005     }
1006 #ifdef G_OS_UNIX
1007   else if (G_IS_SOCKET_OUTPUT_STREAM (ostream) && data->total_written == 0)
1008     {
1009       GOutputVector vector;
1010       GSocketControlMessage *control_message;
1011       gssize bytes_written;
1012       GError *error;
1013
1014       vector.buffer = data->blob;
1015       vector.size = data->blob_size;
1016
1017       control_message = NULL;
1018       if (fd_list != NULL && g_unix_fd_list_get_length (fd_list) > 0)
1019         {
1020           if (!(data->worker->capabilities & G_DBUS_CAPABILITY_FLAGS_UNIX_FD_PASSING))
1021             {
1022               g_simple_async_result_set_error (simple,
1023                                                G_IO_ERROR,
1024                                                G_IO_ERROR_FAILED,
1025                                                "Tried sending a file descriptor but remote peer does not support this capability");
1026               g_simple_async_result_complete (simple);
1027               g_object_unref (simple);
1028               goto out;
1029             }
1030           control_message = g_unix_fd_message_new_with_fd_list (fd_list);
1031         }
1032
1033       error = NULL;
1034       bytes_written = g_socket_send_message (data->worker->socket,
1035                                              NULL, /* address */
1036                                              &vector,
1037                                              1,
1038                                              control_message != NULL ? &control_message : NULL,
1039                                              control_message != NULL ? 1 : 0,
1040                                              G_SOCKET_MSG_NONE,
1041                                              data->worker->cancellable,
1042                                              &error);
1043       if (control_message != NULL)
1044         g_object_unref (control_message);
1045
1046       if (bytes_written == -1)
1047         {
1048           /* Handle WOULD_BLOCK by waiting until there's room in the buffer */
1049           if (g_error_matches (error, G_IO_ERROR, G_IO_ERROR_WOULD_BLOCK))
1050             {
1051               GSource *source;
1052               source = g_socket_create_source (data->worker->socket,
1053                                                G_IO_OUT | G_IO_HUP | G_IO_ERR,
1054                                                data->worker->cancellable);
1055               g_source_set_callback (source,
1056                                      (GSourceFunc) on_socket_ready,
1057                                      data,
1058                                      NULL); /* GDestroyNotify */
1059               g_source_attach (source, g_main_context_get_thread_default ());
1060               g_source_unref (source);
1061               g_error_free (error);
1062               goto out;
1063             }
1064           g_simple_async_result_take_error (simple, error);
1065           g_simple_async_result_complete (simple);
1066           g_object_unref (simple);
1067           goto out;
1068         }
1069       g_assert (bytes_written > 0); /* zero is never returned */
1070
1071       write_message_print_transport_debug (bytes_written, data);
1072
1073       data->total_written += bytes_written;
1074       g_assert (data->total_written <= data->blob_size);
1075       if (data->total_written == data->blob_size)
1076         {
1077           g_simple_async_result_complete (simple);
1078           g_object_unref (simple);
1079           goto out;
1080         }
1081
1082       write_message_continue_writing (data);
1083     }
1084 #endif
1085   else
1086     {
1087 #ifdef G_OS_UNIX
1088       if (fd_list != NULL)
1089         {
1090           g_simple_async_result_set_error (simple,
1091                                            G_IO_ERROR,
1092                                            G_IO_ERROR_FAILED,
1093                                            "Tried sending a file descriptor on unsupported stream of type %s",
1094                                            g_type_name (G_TYPE_FROM_INSTANCE (ostream)));
1095           g_simple_async_result_complete (simple);
1096           g_object_unref (simple);
1097           goto out;
1098         }
1099 #endif
1100
1101       g_output_stream_write_async (ostream,
1102                                    (const gchar *) data->blob + data->total_written,
1103                                    data->blob_size - data->total_written,
1104                                    G_PRIORITY_DEFAULT,
1105                                    data->worker->cancellable,
1106                                    write_message_async_cb,
1107                                    data);
1108     }
1109  out:
1110   ;
1111 }
1112
1113 /* called in private thread shared by all GDBusConnection instances
1114  *
1115  * write-lock is not held on entry
1116  * output_pending is PENDING_WRITE on entry
1117  */
1118 static void
1119 write_message_async (GDBusWorker         *worker,
1120                      MessageToWriteData  *data,
1121                      GAsyncReadyCallback  callback,
1122                      gpointer             user_data)
1123 {
1124   data->simple = g_simple_async_result_new (NULL,
1125                                             callback,
1126                                             user_data,
1127                                             write_message_async);
1128   data->total_written = 0;
1129   write_message_continue_writing (data);
1130 }
1131
1132 /* called in private thread shared by all GDBusConnection instances (with write-lock held) */
1133 static gboolean
1134 write_message_finish (GAsyncResult   *res,
1135                       GError        **error)
1136 {
1137   g_warn_if_fail (g_simple_async_result_get_source_tag (G_SIMPLE_ASYNC_RESULT (res)) == write_message_async);
1138   if (g_simple_async_result_propagate_error (G_SIMPLE_ASYNC_RESULT (res), error))
1139     return FALSE;
1140   else
1141     return TRUE;
1142 }
1143 /* ---------------------------------------------------------------------------------------------------- */
1144
1145 static void continue_writing (GDBusWorker *worker);
1146
1147 typedef struct
1148 {
1149   GDBusWorker *worker;
1150   GList *flushers;
1151 } FlushAsyncData;
1152
1153 static void
1154 flush_data_list_complete (const GList  *flushers,
1155                           const GError *error)
1156 {
1157   const GList *l;
1158
1159   for (l = flushers; l != NULL; l = l->next)
1160     {
1161       FlushData *f = l->data;
1162
1163       f->error = error != NULL ? g_error_copy (error) : NULL;
1164
1165       g_mutex_lock (&f->mutex);
1166       g_cond_signal (&f->cond);
1167       g_mutex_unlock (&f->mutex);
1168     }
1169 }
1170
1171 /* called in private thread shared by all GDBusConnection instances
1172  *
1173  * write-lock is not held on entry
1174  * output_pending is PENDING_FLUSH on entry
1175  */
1176 static void
1177 ostream_flush_cb (GObject      *source_object,
1178                   GAsyncResult *res,
1179                   gpointer      user_data)
1180 {
1181   FlushAsyncData *data = user_data;
1182   GError *error;
1183
1184   error = NULL;
1185   g_output_stream_flush_finish (G_OUTPUT_STREAM (source_object),
1186                                 res,
1187                                 &error);
1188
1189   if (error == NULL)
1190     {
1191       if (G_UNLIKELY (_g_dbus_debug_transport ()))
1192         {
1193           _g_dbus_debug_print_lock ();
1194           g_print ("========================================================================\n"
1195                    "GDBus-debug:Transport:\n"
1196                    "  ---- FLUSHED stream of type %s\n",
1197                    g_type_name (G_TYPE_FROM_INSTANCE (g_io_stream_get_output_stream (data->worker->stream))));
1198           _g_dbus_debug_print_unlock ();
1199         }
1200     }
1201
1202   g_assert (data->flushers != NULL);
1203   flush_data_list_complete (data->flushers, error);
1204   g_list_free (data->flushers);
1205
1206   if (error != NULL)
1207     g_error_free (error);
1208
1209   /* Make sure we tell folks that we don't have additional
1210      flushes pending */
1211   g_mutex_lock (&data->worker->write_lock);
1212   data->worker->write_num_messages_flushed = data->worker->write_num_messages_written;
1213   g_assert (data->worker->output_pending == PENDING_FLUSH);
1214   data->worker->output_pending = PENDING_NONE;
1215   g_mutex_unlock (&data->worker->write_lock);
1216
1217   /* OK, cool, finally kick off the next write */
1218   continue_writing (data->worker);
1219
1220   _g_dbus_worker_unref (data->worker);
1221   g_free (data);
1222 }
1223
1224 /* called in private thread shared by all GDBusConnection instances
1225  *
1226  * write-lock is not held on entry
1227  * output_pending is PENDING_FLUSH on entry
1228  */
1229 static void
1230 start_flush (FlushAsyncData *data)
1231 {
1232   g_output_stream_flush_async (g_io_stream_get_output_stream (data->worker->stream),
1233                                G_PRIORITY_DEFAULT,
1234                                data->worker->cancellable,
1235                                ostream_flush_cb,
1236                                data);
1237 }
1238
1239 /* called in private thread shared by all GDBusConnection instances
1240  *
1241  * write-lock is held on entry
1242  * output_pending is PENDING_NONE on entry
1243  */
1244 static void
1245 message_written_unlocked (GDBusWorker *worker,
1246                           MessageToWriteData *message_data)
1247 {
1248   if (G_UNLIKELY (_g_dbus_debug_message ()))
1249     {
1250       gchar *s;
1251       _g_dbus_debug_print_lock ();
1252       g_print ("========================================================================\n"
1253                "GDBus-debug:Message:\n"
1254                "  >>>> SENT D-Bus message (%" G_GSIZE_FORMAT " bytes)\n",
1255                message_data->blob_size);
1256       s = g_dbus_message_print (message_data->message, 2);
1257       g_print ("%s", s);
1258       g_free (s);
1259       if (G_UNLIKELY (_g_dbus_debug_payload ()))
1260         {
1261           s = _g_dbus_hexdump (message_data->blob, message_data->blob_size, 2);
1262           g_print ("%s\n", s);
1263           g_free (s);
1264         }
1265       _g_dbus_debug_print_unlock ();
1266     }
1267
1268   worker->write_num_messages_written += 1;
1269 }
1270
1271 /* called in private thread shared by all GDBusConnection instances
1272  *
1273  * write-lock is held on entry
1274  * output_pending is PENDING_NONE on entry
1275  *
1276  * Returns: non-%NULL, setting @output_pending, if we need to flush now
1277  */
1278 static FlushAsyncData *
1279 prepare_flush_unlocked (GDBusWorker *worker)
1280 {
1281   GList *l;
1282   GList *ll;
1283   GList *flushers;
1284
1285   flushers = NULL;
1286   for (l = worker->write_pending_flushes; l != NULL; l = ll)
1287     {
1288       FlushData *f = l->data;
1289       ll = l->next;
1290
1291       if (f->number_to_wait_for == worker->write_num_messages_written)
1292         {
1293           flushers = g_list_append (flushers, f);
1294           worker->write_pending_flushes = g_list_delete_link (worker->write_pending_flushes, l);
1295         }
1296     }
1297   if (flushers != NULL)
1298     {
1299       g_assert (worker->output_pending == PENDING_NONE);
1300       worker->output_pending = PENDING_FLUSH;
1301     }
1302
1303   if (flushers != NULL)
1304     {
1305       FlushAsyncData *data;
1306
1307       data = g_new0 (FlushAsyncData, 1);
1308       data->worker = _g_dbus_worker_ref (worker);
1309       data->flushers = flushers;
1310       return data;
1311     }
1312
1313   return NULL;
1314 }
1315
1316 /* called in private thread shared by all GDBusConnection instances
1317  *
1318  * write-lock is not held on entry
1319  * output_pending is PENDING_WRITE on entry
1320  */
1321 static void
1322 write_message_cb (GObject       *source_object,
1323                   GAsyncResult  *res,
1324                   gpointer       user_data)
1325 {
1326   MessageToWriteData *data = user_data;
1327   GError *error;
1328
1329   g_mutex_lock (&data->worker->write_lock);
1330   g_assert (data->worker->output_pending == PENDING_WRITE);
1331   data->worker->output_pending = PENDING_NONE;
1332
1333   error = NULL;
1334   if (!write_message_finish (res, &error))
1335     {
1336       g_mutex_unlock (&data->worker->write_lock);
1337
1338       /* TODO: handle */
1339       _g_dbus_worker_emit_disconnected (data->worker, TRUE, error);
1340       g_error_free (error);
1341
1342       g_mutex_lock (&data->worker->write_lock);
1343     }
1344
1345   message_written_unlocked (data->worker, data);
1346
1347   g_mutex_unlock (&data->worker->write_lock);
1348
1349   continue_writing (data->worker);
1350
1351   message_to_write_data_free (data);
1352 }
1353
1354 /* called in private thread shared by all GDBusConnection instances
1355  *
1356  * write-lock is not held on entry
1357  * output_pending is PENDING_CLOSE on entry
1358  */
1359 static void
1360 iostream_close_cb (GObject      *source_object,
1361                    GAsyncResult *res,
1362                    gpointer      user_data)
1363 {
1364   GDBusWorker *worker = user_data;
1365   GError *error = NULL;
1366   GList *pending_close_attempts, *pending_flush_attempts;
1367   GQueue *send_queue;
1368
1369   g_io_stream_close_finish (worker->stream, res, &error);
1370
1371   g_mutex_lock (&worker->write_lock);
1372
1373   pending_close_attempts = worker->pending_close_attempts;
1374   worker->pending_close_attempts = NULL;
1375
1376   pending_flush_attempts = worker->write_pending_flushes;
1377   worker->write_pending_flushes = NULL;
1378
1379   send_queue = worker->write_queue;
1380   worker->write_queue = g_queue_new ();
1381
1382   g_assert (worker->output_pending == PENDING_CLOSE);
1383   worker->output_pending = PENDING_NONE;
1384
1385   g_mutex_unlock (&worker->write_lock);
1386
1387   while (pending_close_attempts != NULL)
1388     {
1389       CloseData *close_data = pending_close_attempts->data;
1390
1391       pending_close_attempts = g_list_delete_link (pending_close_attempts,
1392                                                    pending_close_attempts);
1393
1394       if (close_data->result != NULL)
1395         {
1396           if (error != NULL)
1397             g_simple_async_result_set_from_error (close_data->result, error);
1398
1399           /* this must be in an idle because the result is likely to be
1400            * intended for another thread
1401            */
1402           g_simple_async_result_complete_in_idle (close_data->result);
1403         }
1404
1405       close_data_free (close_data);
1406     }
1407
1408   g_clear_error (&error);
1409
1410   /* all messages queued for sending are discarded */
1411   g_queue_free_full (send_queue, (GDestroyNotify) message_to_write_data_free);
1412   /* all queued flushes fail */
1413   error = g_error_new (G_IO_ERROR, G_IO_ERROR_CANCELLED,
1414                        _("Operation was cancelled"));
1415   flush_data_list_complete (pending_flush_attempts, error);
1416   g_list_free (pending_flush_attempts);
1417   g_clear_error (&error);
1418
1419   _g_dbus_worker_unref (worker);
1420 }
1421
1422 /* called in private thread shared by all GDBusConnection instances
1423  *
1424  * write-lock is not held on entry
1425  * output_pending must be PENDING_NONE on entry
1426  */
1427 static void
1428 continue_writing (GDBusWorker *worker)
1429 {
1430   MessageToWriteData *data;
1431   FlushAsyncData *flush_async_data;
1432
1433  write_next:
1434   /* we mustn't try to write two things at once */
1435   g_assert (worker->output_pending == PENDING_NONE);
1436
1437   g_mutex_lock (&worker->write_lock);
1438
1439   data = NULL;
1440   flush_async_data = NULL;
1441
1442   /* if we want to close the connection, that takes precedence */
1443   if (worker->pending_close_attempts != NULL)
1444     {
1445       worker->close_expected = TRUE;
1446       worker->output_pending = PENDING_CLOSE;
1447
1448       g_io_stream_close_async (worker->stream, G_PRIORITY_DEFAULT,
1449                                NULL, iostream_close_cb,
1450                                _g_dbus_worker_ref (worker));
1451     }
1452   else
1453     {
1454       flush_async_data = prepare_flush_unlocked (worker);
1455
1456       if (flush_async_data == NULL)
1457         {
1458           data = g_queue_pop_head (worker->write_queue);
1459
1460           if (data != NULL)
1461             worker->output_pending = PENDING_WRITE;
1462         }
1463     }
1464
1465   g_mutex_unlock (&worker->write_lock);
1466
1467   /* Note that write_lock is only used for protecting the @write_queue
1468    * and @output_pending fields of the GDBusWorker struct ... which we
1469    * need to modify from arbitrary threads in _g_dbus_worker_send_message().
1470    *
1471    * Therefore, it's fine to drop it here when calling back into user
1472    * code and then writing the message out onto the GIOStream since this
1473    * function only runs on the worker thread.
1474    */
1475
1476   if (flush_async_data != NULL)
1477     {
1478       start_flush (flush_async_data);
1479       g_assert (data == NULL);
1480     }
1481   else if (data != NULL)
1482     {
1483       GDBusMessage *old_message;
1484       guchar *new_blob;
1485       gsize new_blob_size;
1486       GError *error;
1487
1488       old_message = data->message;
1489       data->message = _g_dbus_worker_emit_message_about_to_be_sent (worker, data->message);
1490       if (data->message == old_message)
1491         {
1492           /* filters had no effect - do nothing */
1493         }
1494       else if (data->message == NULL)
1495         {
1496           /* filters dropped message */
1497           g_mutex_lock (&worker->write_lock);
1498           worker->output_pending = PENDING_NONE;
1499           g_mutex_unlock (&worker->write_lock);
1500           message_to_write_data_free (data);
1501           goto write_next;
1502         }
1503       else
1504         {
1505           /* filters altered the message -> reencode */
1506           error = NULL;
1507           new_blob = g_dbus_message_to_blob (data->message,
1508                                              &new_blob_size,
1509                                              worker->capabilities,
1510                                              &error);
1511           if (new_blob == NULL)
1512             {
1513               /* if filter make the GDBusMessage unencodeable, just complain on stderr and send
1514                * the old message instead
1515                */
1516               g_warning ("Error encoding GDBusMessage with serial %d altered by filter function: %s",
1517                          g_dbus_message_get_serial (data->message),
1518                          error->message);
1519               g_error_free (error);
1520             }
1521           else
1522             {
1523               g_free (data->blob);
1524               data->blob = (gchar *) new_blob;
1525               data->blob_size = new_blob_size;
1526             }
1527         }
1528
1529       write_message_async (worker,
1530                            data,
1531                            write_message_cb,
1532                            data);
1533     }
1534 }
1535
1536 /* called in private thread shared by all GDBusConnection instances
1537  *
1538  * write-lock is not held on entry
1539  * output_pending may be anything
1540  */
1541 static gboolean
1542 continue_writing_in_idle_cb (gpointer user_data)
1543 {
1544   GDBusWorker *worker = user_data;
1545
1546   /* Because this is the worker thread, we can read this struct member
1547    * without holding the lock: no other thread ever modifies it.
1548    */
1549   if (worker->output_pending == PENDING_NONE)
1550     continue_writing (worker);
1551
1552   return FALSE;
1553 }
1554
1555 /*
1556  * @write_data: (transfer full) (allow-none):
1557  * @flush_data: (transfer full) (allow-none):
1558  * @close_data: (transfer full) (allow-none):
1559  *
1560  * Can be called from any thread
1561  *
1562  * write_lock is held on entry
1563  * output_pending may be anything
1564  */
1565 static void
1566 schedule_writing_unlocked (GDBusWorker        *worker,
1567                            MessageToWriteData *write_data,
1568                            FlushData          *flush_data,
1569                            CloseData          *close_data)
1570 {
1571   if (write_data != NULL)
1572     g_queue_push_tail (worker->write_queue, write_data);
1573
1574   if (flush_data != NULL)
1575     worker->write_pending_flushes = g_list_prepend (worker->write_pending_flushes, flush_data);
1576
1577   if (close_data != NULL)
1578     worker->pending_close_attempts = g_list_prepend (worker->pending_close_attempts,
1579                                                      close_data);
1580
1581   /* If we had output pending, the next bit of output will happen
1582    * automatically when it finishes, so we only need to do this
1583    * if nothing was pending.
1584    *
1585    * The idle callback will re-check that output_pending is still
1586    * PENDING_NONE, to guard against output starting before the idle.
1587    */
1588   if (worker->output_pending == PENDING_NONE)
1589     {
1590       GSource *idle_source;
1591       idle_source = g_idle_source_new ();
1592       g_source_set_priority (idle_source, G_PRIORITY_DEFAULT);
1593       g_source_set_callback (idle_source,
1594                              continue_writing_in_idle_cb,
1595                              _g_dbus_worker_ref (worker),
1596                              (GDestroyNotify) _g_dbus_worker_unref);
1597       g_source_attach (idle_source, worker->shared_thread_data->context);
1598       g_source_unref (idle_source);
1599     }
1600 }
1601
1602 /* ---------------------------------------------------------------------------------------------------- */
1603
1604 /* can be called from any thread - steals blob
1605  *
1606  * write_lock is not held on entry
1607  * output_pending may be anything
1608  */
1609 void
1610 _g_dbus_worker_send_message (GDBusWorker    *worker,
1611                              GDBusMessage   *message,
1612                              gchar          *blob,
1613                              gsize           blob_len)
1614 {
1615   MessageToWriteData *data;
1616
1617   g_return_if_fail (G_IS_DBUS_MESSAGE (message));
1618   g_return_if_fail (blob != NULL);
1619   g_return_if_fail (blob_len > 16);
1620
1621   data = g_new0 (MessageToWriteData, 1);
1622   data->worker = _g_dbus_worker_ref (worker);
1623   data->message = g_object_ref (message);
1624   data->blob = blob; /* steal! */
1625   data->blob_size = blob_len;
1626
1627   g_mutex_lock (&worker->write_lock);
1628   schedule_writing_unlocked (worker, data, NULL, NULL);
1629   g_mutex_unlock (&worker->write_lock);
1630 }
1631
1632 /* ---------------------------------------------------------------------------------------------------- */
1633
1634 GDBusWorker *
1635 _g_dbus_worker_new (GIOStream                              *stream,
1636                     GDBusCapabilityFlags                    capabilities,
1637                     gboolean                                initially_frozen,
1638                     GDBusWorkerMessageReceivedCallback      message_received_callback,
1639                     GDBusWorkerMessageAboutToBeSentCallback message_about_to_be_sent_callback,
1640                     GDBusWorkerDisconnectedCallback         disconnected_callback,
1641                     gpointer                                user_data)
1642 {
1643   GDBusWorker *worker;
1644   GSource *idle_source;
1645
1646   g_return_val_if_fail (G_IS_IO_STREAM (stream), NULL);
1647   g_return_val_if_fail (message_received_callback != NULL, NULL);
1648   g_return_val_if_fail (message_about_to_be_sent_callback != NULL, NULL);
1649   g_return_val_if_fail (disconnected_callback != NULL, NULL);
1650
1651   worker = g_new0 (GDBusWorker, 1);
1652   worker->ref_count = 1;
1653
1654   g_mutex_init (&worker->read_lock);
1655   worker->message_received_callback = message_received_callback;
1656   worker->message_about_to_be_sent_callback = message_about_to_be_sent_callback;
1657   worker->disconnected_callback = disconnected_callback;
1658   worker->user_data = user_data;
1659   worker->stream = g_object_ref (stream);
1660   worker->capabilities = capabilities;
1661   worker->cancellable = g_cancellable_new ();
1662   worker->output_pending = PENDING_NONE;
1663
1664   worker->frozen = initially_frozen;
1665   worker->received_messages_while_frozen = g_queue_new ();
1666
1667   g_mutex_init (&worker->write_lock);
1668   worker->write_queue = g_queue_new ();
1669
1670   if (G_IS_SOCKET_CONNECTION (worker->stream))
1671     worker->socket = g_socket_connection_get_socket (G_SOCKET_CONNECTION (worker->stream));
1672
1673   worker->shared_thread_data = _g_dbus_shared_thread_ref ();
1674
1675   /* begin reading */
1676   idle_source = g_idle_source_new ();
1677   g_source_set_priority (idle_source, G_PRIORITY_DEFAULT);
1678   g_source_set_callback (idle_source,
1679                          _g_dbus_worker_do_initial_read,
1680                          _g_dbus_worker_ref (worker),
1681                          (GDestroyNotify) _g_dbus_worker_unref);
1682   g_source_attach (idle_source, worker->shared_thread_data->context);
1683   g_source_unref (idle_source);
1684
1685   return worker;
1686 }
1687
1688 /* ---------------------------------------------------------------------------------------------------- */
1689
1690 /* can be called from any thread
1691  *
1692  * write_lock is not held on entry
1693  * output_pending may be anything
1694  */
1695 void
1696 _g_dbus_worker_close (GDBusWorker         *worker,
1697                       GCancellable        *cancellable,
1698                       GSimpleAsyncResult  *result)
1699 {
1700   CloseData *close_data;
1701
1702   close_data = g_slice_new0 (CloseData);
1703   close_data->worker = _g_dbus_worker_ref (worker);
1704   close_data->cancellable =
1705       (cancellable == NULL ? NULL : g_object_ref (cancellable));
1706   close_data->result = (result == NULL ? NULL : g_object_ref (result));
1707
1708   /* Don't set worker->close_expected here - we're in the wrong thread.
1709    * It'll be set before the actual close happens.
1710    */
1711   g_cancellable_cancel (worker->cancellable);
1712   g_mutex_lock (&worker->write_lock);
1713   schedule_writing_unlocked (worker, NULL, NULL, close_data);
1714   g_mutex_unlock (&worker->write_lock);
1715 }
1716
1717 /* This can be called from any thread - frees worker. Note that
1718  * callbacks might still happen if called from another thread than the
1719  * worker - use your own synchronization primitive in the callbacks.
1720  *
1721  * write_lock is not held on entry
1722  * output_pending may be anything
1723  */
1724 void
1725 _g_dbus_worker_stop (GDBusWorker *worker)
1726 {
1727   g_atomic_int_set (&worker->stopped, TRUE);
1728
1729   /* Cancel any pending operations and schedule a close of the underlying I/O
1730    * stream in the worker thread
1731    */
1732   _g_dbus_worker_close (worker, NULL, NULL);
1733
1734   /* _g_dbus_worker_close holds a ref until after an idle in the worker
1735    * thread has run, so we no longer need to unref in an idle like in
1736    * commit 322e25b535
1737    */
1738   _g_dbus_worker_unref (worker);
1739 }
1740
1741 /* ---------------------------------------------------------------------------------------------------- */
1742
1743 /* can be called from any thread (except the worker thread) - blocks
1744  * calling thread until all queued outgoing messages are written and
1745  * the transport has been flushed
1746  *
1747  * write_lock is not held on entry
1748  * output_pending may be anything
1749  */
1750 gboolean
1751 _g_dbus_worker_flush_sync (GDBusWorker    *worker,
1752                            GCancellable   *cancellable,
1753                            GError        **error)
1754 {
1755   gboolean ret;
1756   FlushData *data;
1757   guint64 pending_writes;
1758
1759   data = NULL;
1760   ret = TRUE;
1761
1762   g_mutex_lock (&worker->write_lock);
1763
1764   /* if the queue is empty, no write is in-flight and we haven't written
1765    * anything since the last flush, then there's nothing to wait for
1766    */
1767   pending_writes = g_queue_get_length (worker->write_queue);
1768
1769   /* if a write is in-flight, we shouldn't be satisfied until the first
1770    * flush operation that follows it
1771    */
1772   if (worker->output_pending == PENDING_WRITE)
1773     pending_writes += 1;
1774
1775   if (pending_writes > 0 ||
1776       worker->write_num_messages_written != worker->write_num_messages_flushed)
1777     {
1778       data = g_new0 (FlushData, 1);
1779       g_mutex_init (&data->mutex);
1780       g_cond_init (&data->cond);
1781       data->number_to_wait_for = worker->write_num_messages_written + pending_writes;
1782       g_mutex_lock (&data->mutex);
1783
1784       schedule_writing_unlocked (worker, NULL, data, NULL);
1785     }
1786   g_mutex_unlock (&worker->write_lock);
1787
1788   if (data != NULL)
1789     {
1790       g_cond_wait (&data->cond, &data->mutex);
1791       g_mutex_unlock (&data->mutex);
1792
1793       /* note:the element is removed from worker->write_pending_flushes in flush_cb() above */
1794       g_cond_clear (&data->cond);
1795       g_mutex_clear (&data->mutex);
1796       if (data->error != NULL)
1797         {
1798           ret = FALSE;
1799           g_propagate_error (error, data->error);
1800         }
1801       g_free (data);
1802     }
1803
1804   return ret;
1805 }
1806
1807 /* ---------------------------------------------------------------------------------------------------- */
1808
1809 #define G_DBUS_DEBUG_AUTHENTICATION (1<<0)
1810 #define G_DBUS_DEBUG_TRANSPORT      (1<<1)
1811 #define G_DBUS_DEBUG_MESSAGE        (1<<2)
1812 #define G_DBUS_DEBUG_PAYLOAD        (1<<3)
1813 #define G_DBUS_DEBUG_CALL           (1<<4)
1814 #define G_DBUS_DEBUG_SIGNAL         (1<<5)
1815 #define G_DBUS_DEBUG_INCOMING       (1<<6)
1816 #define G_DBUS_DEBUG_RETURN         (1<<7)
1817 #define G_DBUS_DEBUG_EMISSION       (1<<8)
1818 #define G_DBUS_DEBUG_ADDRESS        (1<<9)
1819
1820 static gint _gdbus_debug_flags = 0;
1821
1822 gboolean
1823 _g_dbus_debug_authentication (void)
1824 {
1825   _g_dbus_initialize ();
1826   return (_gdbus_debug_flags & G_DBUS_DEBUG_AUTHENTICATION) != 0;
1827 }
1828
1829 gboolean
1830 _g_dbus_debug_transport (void)
1831 {
1832   _g_dbus_initialize ();
1833   return (_gdbus_debug_flags & G_DBUS_DEBUG_TRANSPORT) != 0;
1834 }
1835
1836 gboolean
1837 _g_dbus_debug_message (void)
1838 {
1839   _g_dbus_initialize ();
1840   return (_gdbus_debug_flags & G_DBUS_DEBUG_MESSAGE) != 0;
1841 }
1842
1843 gboolean
1844 _g_dbus_debug_payload (void)
1845 {
1846   _g_dbus_initialize ();
1847   return (_gdbus_debug_flags & G_DBUS_DEBUG_PAYLOAD) != 0;
1848 }
1849
1850 gboolean
1851 _g_dbus_debug_call (void)
1852 {
1853   _g_dbus_initialize ();
1854   return (_gdbus_debug_flags & G_DBUS_DEBUG_CALL) != 0;
1855 }
1856
1857 gboolean
1858 _g_dbus_debug_signal (void)
1859 {
1860   _g_dbus_initialize ();
1861   return (_gdbus_debug_flags & G_DBUS_DEBUG_SIGNAL) != 0;
1862 }
1863
1864 gboolean
1865 _g_dbus_debug_incoming (void)
1866 {
1867   _g_dbus_initialize ();
1868   return (_gdbus_debug_flags & G_DBUS_DEBUG_INCOMING) != 0;
1869 }
1870
1871 gboolean
1872 _g_dbus_debug_return (void)
1873 {
1874   _g_dbus_initialize ();
1875   return (_gdbus_debug_flags & G_DBUS_DEBUG_RETURN) != 0;
1876 }
1877
1878 gboolean
1879 _g_dbus_debug_emission (void)
1880 {
1881   _g_dbus_initialize ();
1882   return (_gdbus_debug_flags & G_DBUS_DEBUG_EMISSION) != 0;
1883 }
1884
1885 gboolean
1886 _g_dbus_debug_address (void)
1887 {
1888   _g_dbus_initialize ();
1889   return (_gdbus_debug_flags & G_DBUS_DEBUG_ADDRESS) != 0;
1890 }
1891
1892 G_LOCK_DEFINE_STATIC (print_lock);
1893
1894 void
1895 _g_dbus_debug_print_lock (void)
1896 {
1897   G_LOCK (print_lock);
1898 }
1899
1900 void
1901 _g_dbus_debug_print_unlock (void)
1902 {
1903   G_UNLOCK (print_lock);
1904 }
1905
1906 /*
1907  * _g_dbus_initialize:
1908  *
1909  * Does various one-time init things such as
1910  *
1911  *  - registering the G_DBUS_ERROR error domain
1912  *  - parses the G_DBUS_DEBUG environment variable
1913  */
1914 void
1915 _g_dbus_initialize (void)
1916 {
1917   static volatile gsize initialized = 0;
1918
1919   if (g_once_init_enter (&initialized))
1920     {
1921       volatile GQuark g_dbus_error_domain;
1922       const gchar *debug;
1923
1924       g_dbus_error_domain = G_DBUS_ERROR;
1925       (g_dbus_error_domain); /* To avoid -Wunused-but-set-variable */
1926
1927       debug = g_getenv ("G_DBUS_DEBUG");
1928       if (debug != NULL)
1929         {
1930           const GDebugKey keys[] = {
1931             { "authentication", G_DBUS_DEBUG_AUTHENTICATION },
1932             { "transport",      G_DBUS_DEBUG_TRANSPORT      },
1933             { "message",        G_DBUS_DEBUG_MESSAGE        },
1934             { "payload",        G_DBUS_DEBUG_PAYLOAD        },
1935             { "call",           G_DBUS_DEBUG_CALL           },
1936             { "signal",         G_DBUS_DEBUG_SIGNAL         },
1937             { "incoming",       G_DBUS_DEBUG_INCOMING       },
1938             { "return",         G_DBUS_DEBUG_RETURN         },
1939             { "emission",       G_DBUS_DEBUG_EMISSION       },
1940             { "address",        G_DBUS_DEBUG_ADDRESS        }
1941           };
1942
1943           _gdbus_debug_flags = g_parse_debug_string (debug, keys, G_N_ELEMENTS (keys));
1944           if (_gdbus_debug_flags & G_DBUS_DEBUG_PAYLOAD)
1945             _gdbus_debug_flags |= G_DBUS_DEBUG_MESSAGE;
1946         }
1947
1948       g_once_init_leave (&initialized, 1);
1949     }
1950 }
1951
1952 /* ---------------------------------------------------------------------------------------------------- */
1953
1954 GVariantType *
1955 _g_dbus_compute_complete_signature (GDBusArgInfo **args)
1956 {
1957   const GVariantType *arg_types[256];
1958   guint n;
1959
1960   if (args)
1961     for (n = 0; args[n] != NULL; n++)
1962       {
1963         /* DBus places a hard limit of 255 on signature length.
1964          * therefore number of args must be less than 256.
1965          */
1966         g_assert (n < 256);
1967
1968         arg_types[n] = G_VARIANT_TYPE (args[n]->signature);
1969
1970         if G_UNLIKELY (arg_types[n] == NULL)
1971           return NULL;
1972       }
1973   else
1974     n = 0;
1975
1976   return g_variant_type_new_tuple (arg_types, n);
1977 }
1978
1979 /* ---------------------------------------------------------------------------------------------------- */
1980
1981 #ifdef G_OS_WIN32
1982
1983 extern BOOL WINAPI ConvertSidToStringSidA (PSID Sid, LPSTR *StringSid);
1984
1985 gchar *
1986 _g_dbus_win32_get_user_sid (void)
1987 {
1988   HANDLE h;
1989   TOKEN_USER *user;
1990   DWORD token_information_len;
1991   PSID psid;
1992   gchar *sid;
1993   gchar *ret;
1994
1995   ret = NULL;
1996   user = NULL;
1997   h = INVALID_HANDLE_VALUE;
1998
1999   if (!OpenProcessToken (GetCurrentProcess (), TOKEN_QUERY, &h))
2000     {
2001       g_warning ("OpenProcessToken failed with error code %d", (gint) GetLastError ());
2002       goto out;
2003     }
2004
2005   /* Get length of buffer */
2006   token_information_len = 0;
2007   if (!GetTokenInformation (h, TokenUser, NULL, 0, &token_information_len))
2008     {
2009       if (GetLastError () != ERROR_INSUFFICIENT_BUFFER)
2010         {
2011           g_warning ("GetTokenInformation() failed with error code %d", (gint) GetLastError ());
2012           goto out;
2013         }
2014     }
2015   user = g_malloc (token_information_len);
2016   if (!GetTokenInformation (h, TokenUser, user, token_information_len, &token_information_len))
2017     {
2018       g_warning ("GetTokenInformation() failed with error code %d", (gint) GetLastError ());
2019       goto out;
2020     }
2021
2022   psid = user->User.Sid;
2023   if (!IsValidSid (psid))
2024     {
2025       g_warning ("Invalid SID");
2026       goto out;
2027     }
2028
2029   if (!ConvertSidToStringSidA (psid, &sid))
2030     {
2031       g_warning ("Invalid SID");
2032       goto out;
2033     }
2034
2035   ret = g_strdup (sid);
2036   LocalFree (sid);
2037
2038 out:
2039   g_free (user);
2040   if (h != INVALID_HANDLE_VALUE)
2041     CloseHandle (h);
2042   return ret;
2043 }
2044 #endif
2045
2046 /* ---------------------------------------------------------------------------------------------------- */
2047
2048 gchar *
2049 _g_dbus_get_machine_id (GError **error)
2050 {
2051 #ifdef G_OS_WIN32
2052   HW_PROFILE_INFOA info;
2053   char *src, *dest, *res;
2054   int i;
2055
2056   if (!GetCurrentHwProfileA (&info))
2057     {
2058       char *message = g_win32_error_message (GetLastError ());
2059       g_set_error (error,
2060                    G_IO_ERROR,
2061                    G_IO_ERROR_FAILED,
2062                    _("Unable to get Hardware profile: %s"), message);
2063       g_free (message);
2064       return NULL;
2065     }
2066
2067   /* Form: {12340001-4980-1920-6788-123456789012} */
2068   src = &info.szHwProfileGuid[0];
2069
2070   res = g_malloc (32+1);
2071   dest = res;
2072
2073   src++; /* Skip { */
2074   for (i = 0; i < 8; i++)
2075     *dest++ = *src++;
2076   src++; /* Skip - */
2077   for (i = 0; i < 4; i++)
2078     *dest++ = *src++;
2079   src++; /* Skip - */
2080   for (i = 0; i < 4; i++)
2081     *dest++ = *src++;
2082   src++; /* Skip - */
2083   for (i = 0; i < 4; i++)
2084     *dest++ = *src++;
2085   src++; /* Skip - */
2086   for (i = 0; i < 12; i++)
2087     *dest++ = *src++;
2088   *dest = 0;
2089
2090   return res;
2091 #else
2092   gchar *ret;
2093   GError *first_error;
2094   /* TODO: use PACKAGE_LOCALSTATEDIR ? */
2095   ret = NULL;
2096   first_error = NULL;
2097   if (!g_file_get_contents ("/var/lib/dbus/machine-id",
2098                             &ret,
2099                             NULL,
2100                             &first_error) &&
2101       !g_file_get_contents ("/etc/machine-id",
2102                             &ret,
2103                             NULL,
2104                             NULL))
2105     {
2106       g_propagate_prefixed_error (error, first_error,
2107                                   _("Unable to load /var/lib/dbus/machine-id or /etc/machine-id: "));
2108     }
2109   else
2110     {
2111       /* ignore the error from the first try, if any */
2112       g_clear_error (&first_error);
2113       /* TODO: validate value */
2114       g_strstrip (ret);
2115     }
2116   return ret;
2117 #endif
2118 }
2119
2120 /* ---------------------------------------------------------------------------------------------------- */
2121
2122 gchar *
2123 _g_dbus_enum_to_string (GType enum_type, gint value)
2124 {
2125   gchar *ret;
2126   GEnumClass *klass;
2127   GEnumValue *enum_value;
2128
2129   klass = g_type_class_ref (enum_type);
2130   enum_value = g_enum_get_value (klass, value);
2131   if (enum_value != NULL)
2132     ret = g_strdup (enum_value->value_nick);
2133   else
2134     ret = g_strdup_printf ("unknown (value %d)", value);
2135   g_type_class_unref (klass);
2136   return ret;
2137 }
2138
2139 /* ---------------------------------------------------------------------------------------------------- */
2140
2141 static void
2142 write_message_print_transport_debug (gssize bytes_written,
2143                                      MessageToWriteData *data)
2144 {
2145   if (G_LIKELY (!_g_dbus_debug_transport ()))
2146     goto out;
2147
2148   _g_dbus_debug_print_lock ();
2149   g_print ("========================================================================\n"
2150            "GDBus-debug:Transport:\n"
2151            "  >>>> WROTE %" G_GSIZE_FORMAT " bytes of message with serial %d and\n"
2152            "       size %" G_GSIZE_FORMAT " from offset %" G_GSIZE_FORMAT " on a %s\n",
2153            bytes_written,
2154            g_dbus_message_get_serial (data->message),
2155            data->blob_size,
2156            data->total_written,
2157            g_type_name (G_TYPE_FROM_INSTANCE (g_io_stream_get_output_stream (data->worker->stream))));
2158   _g_dbus_debug_print_unlock ();
2159  out:
2160   ;
2161 }
2162
2163 /* ---------------------------------------------------------------------------------------------------- */
2164
2165 static void
2166 read_message_print_transport_debug (gssize bytes_read,
2167                                     GDBusWorker *worker)
2168 {
2169   gsize size;
2170   gint32 serial;
2171   gint32 message_length;
2172
2173   if (G_LIKELY (!_g_dbus_debug_transport ()))
2174     goto out;
2175
2176   size = bytes_read + worker->read_buffer_cur_size;
2177   serial = 0;
2178   message_length = 0;
2179   if (size >= 16)
2180     message_length = g_dbus_message_bytes_needed ((guchar *) worker->read_buffer, size, NULL);
2181   if (size >= 1)
2182     {
2183       switch (worker->read_buffer[0])
2184         {
2185         case 'l':
2186           if (size >= 12)
2187             serial = GUINT32_FROM_LE (((guint32 *) worker->read_buffer)[2]);
2188           break;
2189         case 'B':
2190           if (size >= 12)
2191             serial = GUINT32_FROM_BE (((guint32 *) worker->read_buffer)[2]);
2192           break;
2193         default:
2194           /* an error will be set elsewhere if this happens */
2195           goto out;
2196         }
2197     }
2198
2199     _g_dbus_debug_print_lock ();
2200   g_print ("========================================================================\n"
2201            "GDBus-debug:Transport:\n"
2202            "  <<<< READ %" G_GSIZE_FORMAT " bytes of message with serial %d and\n"
2203            "       size %d to offset %" G_GSIZE_FORMAT " from a %s\n",
2204            bytes_read,
2205            serial,
2206            message_length,
2207            worker->read_buffer_cur_size,
2208            g_type_name (G_TYPE_FROM_INSTANCE (g_io_stream_get_input_stream (worker->stream))));
2209   _g_dbus_debug_print_unlock ();
2210  out:
2211   ;
2212 }
2213
2214 /* ---------------------------------------------------------------------------------------------------- */
2215
2216 gboolean
2217 _g_signal_accumulator_false_handled (GSignalInvocationHint *ihint,
2218                                      GValue                *return_accu,
2219                                      const GValue          *handler_return,
2220                                      gpointer               dummy)
2221 {
2222   gboolean continue_emission;
2223   gboolean signal_return;
2224
2225   signal_return = g_value_get_boolean (handler_return);
2226   g_value_set_boolean (return_accu, signal_return);
2227   continue_emission = signal_return;
2228
2229   return continue_emission;
2230 }