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, see <http://www.gnu.org/licenses/>.
  17  *
  18  * Author: David Zeuthen <davidz@redhat.com>
  19  */
  20
  21 #include "config.h"
  22
  23 #include <stdlib.h>
  24 #include <string.h>
  25
  26 #include "giotypes.h"
  27 #include "gsocket.h"
  28 #include "gdbusprivate.h"
  29 #include "gdbusmessage.h"
  30 #include "gdbuserror.h"
  31 #include "gdbusintrospection.h"
  32 #include "gtask.h"
  33 #include "ginputstream.h"
  34 #include "gmemoryinputstream.h"
  35 #include "giostream.h"
  36 #include "glib/gstdio.h"
  37 #include "gsocketcontrolmessage.h"
  38 #include "gsocketconnection.h"
  39 #include "gsocketoutputstream.h"
  40
  41 #ifdef G_OS_UNIX
  42 #include "gunixfdmessage.h"
  43 #include "gunixconnection.h"
  44 #include "gunixcredentialsmessage.h"
  45 #endif
  46
  47 #ifdef G_OS_WIN32
  48 #include <windows.h>
  49 #endif
  50
  51 #include "glibintl.h"
  52
  53 static gboolean _g_dbus_worker_do_initial_read (gpointer data);
  54 static void schedule_pending_close (GDBusWorker *worker);
  55
  56 /* ---------------------------------------------------------------------------------------------------- */
  57
  58 gchar *
  59 _g_dbus_hexdump (const gchar *data, gsize len, guint indent)
  60 {
  61  guint n, m;
  62  GString *ret;
  63
  64  ret = g_string_new (NULL);
  65
  66  for (n = 0; n < len; n += 16)
  67    {
  68      g_string_append_printf (ret, "%*s%04x: ", indent, "", n);
  69
  70      for (m = n; m < n + 16; m++)
  71        {
  72          if (m > n && (m%4) == 0)
  73            g_string_append_c (ret, ' ');
  74          if (m < len)
  75            g_string_append_printf (ret, "%02x ", (guchar) data[m]);
  76          else
  77            g_string_append (ret, "   ");
  78        }
  79
  80      g_string_append (ret, "   ");
  81
  82      for (m = n; m < len && m < n + 16; m++)
  83        g_string_append_c (ret, g_ascii_isprint (data[m]) ? data[m] : '.');
  84
  85      g_string_append_c (ret, '\n');
  86    }
  87
  88  return g_string_free (ret, FALSE);
  89 }
  90
  91 /* ---------------------------------------------------------------------------------------------------- */
  92
  93 /* Unfortunately ancillary messages are discarded when reading from a
  94  * socket using the GSocketInputStream abstraction. So we provide a
  95  * very GInputStream-ish API that uses GSocket in this case (very
  96  * similar to GSocketInputStream).
  97  */
  98
  99 typedef struct
 100 {
 101   void *buffer;
 102   gsize count;
 103
 104   GSocketControlMessage ***messages;
 105   gint *num_messages;
 106 } ReadWithControlData;
 107
 108 static void
 109 read_with_control_data_free (ReadWithControlData *data)
 110 {
 111   g_slice_free (ReadWithControlData, data);
 112 }
 113
 114 static gboolean
 115 _g_socket_read_with_control_messages_ready (GSocket      *socket,
 116                                             GIOCondition  condition,
 117                                             gpointer      user_data)
 118 {
 119   GTask *task = user_data;
 120   ReadWithControlData *data = g_task_get_task_data (task);
 121   GError *error;
 122   gssize result;
 123   GInputVector vector;
 124
 125   error = NULL;
 126   vector.buffer = data->buffer;
 127   vector.size = data->count;
 128   result = g_socket_receive_message (socket,
 129                                      NULL, /* address */
 130                                      &vector,
 131                                      1,
 132                                      data->messages,
 133                                      data->num_messages,
 134                                      NULL,
 135                                      g_task_get_cancellable (task),
 136                                      &error);
 137
 138   if (g_error_matches (error, G_IO_ERROR, G_IO_ERROR_WOULD_BLOCK))
 139     {
 140       g_error_free (error);
 141       return TRUE;
 142     }
 143
 144   g_assert (result >= 0 || error != NULL);
 145   if (result >= 0)
 146     g_task_return_int (task, result);
 147   else
 148     g_task_return_error (task, error);
 149   g_object_unref (task);
 150
 151   return FALSE;
 152 }
 153
 154 static void
 155 _g_socket_read_with_control_messages (GSocket                 *socket,
 156                                       void                    *buffer,
 157                                       gsize                    count,
 158                                       GSocketControlMessage ***messages,
 159                                       gint                    *num_messages,
 160                                       gint                     io_priority,
 161                                       GCancellable            *cancellable,
 162                                       GAsyncReadyCallback      callback,
 163                                       gpointer                 user_data)
 164 {
 165   GTask *task;
 166   ReadWithControlData *data;
 167   GSource *source;
 168
 169   data = g_slice_new0 (ReadWithControlData);
 170   data->buffer = buffer;
 171   data->count = count;
 172   data->messages = messages;
 173   data->num_messages = num_messages;
 174
 175   task = g_task_new (socket, cancellable, callback, user_data);
 176   g_task_set_source_tag (task, _g_socket_read_with_control_messages);
 177   g_task_set_task_data (task, data, (GDestroyNotify) read_with_control_data_free);
 178
 179   if (g_socket_condition_check (socket, G_IO_IN))
 180     {
 181       if (!_g_socket_read_with_control_messages_ready (socket, G_IO_IN, task))
 182         return;
 183     }
 184
 185   source = g_socket_create_source (socket,
 186                                    G_IO_IN | G_IO_HUP | G_IO_ERR,
 187                                    cancellable);
 188   g_task_attach_source (task, source, (GSourceFunc) _g_socket_read_with_control_messages_ready);
 189   g_source_unref (source);
 190 }
 191
 192 static gssize
 193 _g_socket_read_with_control_messages_finish (GSocket       *socket,
 194                                              GAsyncResult  *result,
 195                                              GError       **error)
 196 {
 197   g_return_val_if_fail (G_IS_SOCKET (socket), -1);
 198   g_return_val_if_fail (g_task_is_valid (result, socket), -1);
 199
 200   return g_task_propagate_int (G_TASK (result), error);
 201 }
 202
 203 /* ---------------------------------------------------------------------------------------------------- */
 204
 205 /* Work-around for https://bugzilla.gnome.org/show_bug.cgi?id=627724 */
 206
 207 static GPtrArray *ensured_classes = NULL;
 208
 209 static void
 210 ensure_type (GType gtype)
 211 {
 212   g_ptr_array_add (ensured_classes, g_type_class_ref (gtype));
 213 }
 214
 215 static void
 216 release_required_types (void)
 217 {
 218   g_ptr_array_foreach (ensured_classes, (GFunc) g_type_class_unref, NULL);
 219   g_ptr_array_unref (ensured_classes);
 220   ensured_classes = NULL;
 221 }
 222
 223 static void
 224 ensure_required_types (void)
 225 {
 226   g_assert (ensured_classes == NULL);
 227   ensured_classes = g_ptr_array_new ();
 228   ensure_type (G_TYPE_TASK);
 229   ensure_type (G_TYPE_MEMORY_INPUT_STREAM);
 230 }
 231 /* ---------------------------------------------------------------------------------------------------- */
 232
 233 typedef struct
 234 {
 235   volatile gint refcount;
 236   GThread *thread;
 237   GMainContext *context;
 238   GMainLoop *loop;
 239 } SharedThreadData;
 240
 241 static gpointer
 242 gdbus_shared_thread_func (gpointer user_data)
 243 {
 244   SharedThreadData *data = user_data;
 245
 246   g_main_context_push_thread_default (data->context);
 247   g_main_loop_run (data->loop);
 248   g_main_context_pop_thread_default (data->context);
 249
 250   release_required_types ();
 251
 252   return NULL;
 253 }
 254
 255 /* ---------------------------------------------------------------------------------------------------- */
 256
 257 static SharedThreadData *
 258 _g_dbus_shared_thread_ref (void)
 259 {
 260   static gsize shared_thread_data = 0;
 261   SharedThreadData *ret;
 262
 263   if (g_once_init_enter (&shared_thread_data))
 264     {
 265       SharedThreadData *data;
 266
 267       /* Work-around for https://bugzilla.gnome.org/show_bug.cgi?id=627724 */
 268       ensure_required_types ();
 269
 270       data = g_new0 (SharedThreadData, 1);
 271       data->refcount = 0;
 272
 273       data->context = g_main_context_new ();
 274       data->loop = g_main_loop_new (data->context, FALSE);
 275       data->thread = g_thread_new ("gdbus",
 276                                    gdbus_shared_thread_func,
 277                                    data);
 278       /* We can cast between gsize and gpointer safely */
 279       g_once_init_leave (&shared_thread_data, (gsize) data);
 280     }
 281
 282   ret = (SharedThreadData*) shared_thread_data;
 283   g_atomic_int_inc (&ret->refcount);
 284   return ret;
 285 }
 286
 287 static void
 288 _g_dbus_shared_thread_unref (SharedThreadData *data)
 289 {
 290   /* TODO: actually destroy the shared thread here */
 291 #if 0
 292   g_assert (data != NULL);
 293   if (g_atomic_int_dec_and_test (&data->refcount))
 294     {
 295       g_main_loop_quit (data->loop);
 296       //g_thread_join (data->thread);
 297       g_main_loop_unref (data->loop);
 298       g_main_context_unref (data->context);
 299     }
 300 #endif
 301 }
 302
 303 /* ---------------------------------------------------------------------------------------------------- */
 304
 305 typedef enum {
 306     PENDING_NONE = 0,
 307     PENDING_WRITE,
 308     PENDING_FLUSH,
 309     PENDING_CLOSE
 310 } OutputPending;
 311
 312 struct GDBusWorker
 313 {
 314   volatile gint                       ref_count;
 315
 316   SharedThreadData                   *shared_thread_data;
 317
 318   /* really a boolean, but GLib 2.28 lacks atomic boolean ops */
 319   volatile gint                       stopped;
 320
 321   /* TODO: frozen (e.g. G_DBUS_CONNECTION_FLAGS_DELAY_MESSAGE_PROCESSING) currently
 322    * only affects messages received from the other peer (since GDBusServer is the
 323    * only user) - we might want it to affect messages sent to the other peer too?
 324    */
 325   gboolean                            frozen;
 326   GDBusCapabilityFlags                capabilities;
 327   GQueue                             *received_messages_while_frozen;
 328
 329   GIOStream                          *stream;
 330   GCancellable                       *cancellable;
 331   GDBusWorkerMessageReceivedCallback  message_received_callback;
 332   GDBusWorkerMessageAboutToBeSentCallback message_about_to_be_sent_callback;
 333   GDBusWorkerDisconnectedCallback     disconnected_callback;
 334   gpointer                            user_data;
 335
 336   /* if not NULL, stream is GSocketConnection */
 337   GSocket *socket;
 338
 339   /* used for reading */
 340   GMutex                              read_lock;
 341   gchar                              *read_buffer;
 342   gsize                               read_buffer_allocated_size;
 343   gsize                               read_buffer_cur_size;
 344   gsize                               read_buffer_bytes_wanted;
 345   GUnixFDList                        *read_fd_list;
 346   GSocketControlMessage             **read_ancillary_messages;
 347   gint                                read_num_ancillary_messages;
 348
 349   /* Whether an async write, flush or close, or none of those, is pending.
 350    * Only the worker thread may change its value, and only with the write_lock.
 351    * Other threads may read its value when holding the write_lock.
 352    * The worker thread may read its value at any time.
 353    */
 354   OutputPending                       output_pending;
 355   /* used for writing */
 356   GMutex                              write_lock;
 357   /* queue of MessageToWriteData, protected by write_lock */
 358   GQueue                             *write_queue;
 359   /* protected by write_lock */
 360   guint64                             write_num_messages_written;
 361   /* number of messages we'd written out last time we flushed;
 362    * protected by write_lock
 363    */
 364   guint64                             write_num_messages_flushed;
 365   /* list of FlushData, protected by write_lock */
 366   GList                              *write_pending_flushes;
 367   /* list of CloseData, protected by write_lock */
 368   GList                              *pending_close_attempts;
 369   /* no lock - only used from the worker thread */
 370   gboolean                            close_expected;
 371 };
 372
 373 static void _g_dbus_worker_unref (GDBusWorker *worker);
 374
 375 /* ---------------------------------------------------------------------------------------------------- */
 376
 377 typedef struct
 378 {
 379   GMutex  mutex;
 380   GCond   cond;
 381   guint64 number_to_wait_for;
 382   GError *error;
 383 } FlushData;
 384
 385 struct _MessageToWriteData ;
 386 typedef struct _MessageToWriteData MessageToWriteData;
 387
 388 static void message_to_write_data_free (MessageToWriteData *data);
 389
 390 static void read_message_print_transport_debug (gssize bytes_read,
 391                                                 GDBusWorker *worker);
 392
 393 static void write_message_print_transport_debug (gssize bytes_written,
 394                                                  MessageToWriteData *data);
 395
 396 typedef struct {
 397     GDBusWorker *worker;
 398     GTask *task;
 399 } CloseData;
 400
 401 static void close_data_free (CloseData *close_data)
 402 {
 403   g_clear_object (&close_data->task);
 404
 405   _g_dbus_worker_unref (close_data->worker);
 406   g_slice_free (CloseData, close_data);
 407 }
 408
 409 /* ---------------------------------------------------------------------------------------------------- */
 410
 411 static GDBusWorker *
 412 _g_dbus_worker_ref (GDBusWorker *worker)
 413 {
 414   g_atomic_int_inc (&worker->ref_count);
 415   return worker;
 416 }
 417
 418 static void
 419 _g_dbus_worker_unref (GDBusWorker *worker)
 420 {
 421   if (g_atomic_int_dec_and_test (&worker->ref_count))
 422     {
 423       g_assert (worker->write_pending_flushes == NULL);
 424
 425       _g_dbus_shared_thread_unref (worker->shared_thread_data);
 426
 427       g_object_unref (worker->stream);
 428
 429       g_mutex_clear (&worker->read_lock);
 430       g_object_unref (worker->cancellable);
 431       if (worker->read_fd_list != NULL)
 432         g_object_unref (worker->read_fd_list);
 433
 434       g_queue_free_full (worker->received_messages_while_frozen, (GDestroyNotify) g_object_unref);
 435       g_mutex_clear (&worker->write_lock);
 436       g_queue_free_full (worker->write_queue, (GDestroyNotify) message_to_write_data_free);
 437       g_free (worker->read_buffer);
 438
 439       g_free (worker);
 440     }
 441 }
 442
 443 static void
 444 _g_dbus_worker_emit_disconnected (GDBusWorker  *worker,
 445                                   gboolean      remote_peer_vanished,
 446                                   GError       *error)
 447 {
 448   if (!g_atomic_int_get (&worker->stopped))
 449     worker->disconnected_callback (worker, remote_peer_vanished, error, worker->user_data);
 450 }
 451
 452 static void
 453 _g_dbus_worker_emit_message_received (GDBusWorker  *worker,
 454                                       GDBusMessage *message)
 455 {
 456   if (!g_atomic_int_get (&worker->stopped))
 457     worker->message_received_callback (worker, message, worker->user_data);
 458 }
 459
 460 static GDBusMessage *
 461 _g_dbus_worker_emit_message_about_to_be_sent (GDBusWorker  *worker,
 462                                               GDBusMessage *message)
 463 {
 464   GDBusMessage *ret;
 465   if (!g_atomic_int_get (&worker->stopped))
 466     ret = worker->message_about_to_be_sent_callback (worker, message, worker->user_data);
 467   else
 468     ret = message;
 469   return ret;
 470 }
 471
 472 /* can only be called from private thread with read-lock held - takes ownership of @message */
 473 static void
 474 _g_dbus_worker_queue_or_deliver_received_message (GDBusWorker  *worker,
 475                                                   GDBusMessage *message)
 476 {
 477   if (worker->frozen || g_queue_get_length (worker->received_messages_while_frozen) > 0)
 478     {
 479       /* queue up */
 480       g_queue_push_tail (worker->received_messages_while_frozen, message);
 481     }
 482   else
 483     {
 484       /* not frozen, nor anything in queue */
 485       _g_dbus_worker_emit_message_received (worker, message);
 486       g_object_unref (message);
 487     }
 488 }
 489
 490 /* called in private thread shared by all GDBusConnection instances (without read-lock held) */
 491 static gboolean
 492 unfreeze_in_idle_cb (gpointer user_data)
 493 {
 494   GDBusWorker *worker = user_data;
 495   GDBusMessage *message;
 496
 497   g_mutex_lock (&worker->read_lock);
 498   if (worker->frozen)
 499     {
 500       while ((message = g_queue_pop_head (worker->received_messages_while_frozen)) != NULL)
 501         {
 502           _g_dbus_worker_emit_message_received (worker, message);
 503           g_object_unref (message);
 504         }
 505       worker->frozen = FALSE;
 506     }
 507   else
 508     {
 509       g_assert (g_queue_get_length (worker->received_messages_while_frozen) == 0);
 510     }
 511   g_mutex_unlock (&worker->read_lock);
 512   return FALSE;
 513 }
 514
 515 /* can be called from any thread */
 516 void
 517 _g_dbus_worker_unfreeze (GDBusWorker *worker)
 518 {
 519   GSource *idle_source;
 520   idle_source = g_idle_source_new ();
 521   g_source_set_priority (idle_source, G_PRIORITY_DEFAULT);
 522   g_source_set_callback (idle_source,
 523                          unfreeze_in_idle_cb,
 524                          _g_dbus_worker_ref (worker),
 525                          (GDestroyNotify) _g_dbus_worker_unref);
 526   g_source_set_name (idle_source, "[gio] unfreeze_in_idle_cb");
 527   g_source_attach (idle_source, worker->shared_thread_data->context);
 528   g_source_unref (idle_source);
 529 }
 530
 531 /* ---------------------------------------------------------------------------------------------------- */
 532
 533 static void _g_dbus_worker_do_read_unlocked (GDBusWorker *worker);
 534
 535 /* called in private thread shared by all GDBusConnection instances (without read-lock held) */
 536 static void
 537 _g_dbus_worker_do_read_cb (GInputStream  *input_stream,
 538                            GAsyncResult  *res,
 539                            gpointer       user_data)
 540 {
 541   GDBusWorker *worker = user_data;
 542   GError *error;
 543   gssize bytes_read;
 544
 545   g_mutex_lock (&worker->read_lock);
 546
 547   /* If already stopped, don't even process the reply */
 548   if (g_atomic_int_get (&worker->stopped))
 549     goto out;
 550
 551   error = NULL;
 552   if (worker->socket == NULL)
 553     bytes_read = g_input_stream_read_finish (g_io_stream_get_input_stream (worker->stream),
 554                                              res,
 555                                              &error);
 556   else
 557     bytes_read = _g_socket_read_with_control_messages_finish (worker->socket,
 558                                                               res,
 559                                                               &error);
 560   if (worker->read_num_ancillary_messages > 0)
 561     {
 562       gint n;
 563       for (n = 0; n < worker->read_num_ancillary_messages; n++)
 564         {
 565           GSocketControlMessage *control_message = G_SOCKET_CONTROL_MESSAGE (worker->read_ancillary_messages[n]);
 566
 567           if (FALSE)
 568             {
 569             }
 570 #ifdef G_OS_UNIX
 571           else if (G_IS_UNIX_FD_MESSAGE (control_message))
 572             {
 573               GUnixFDMessage *fd_message;
 574               gint *fds;
 575               gint num_fds;
 576
 577               fd_message = G_UNIX_FD_MESSAGE (control_message);
 578               fds = g_unix_fd_message_steal_fds (fd_message, &num_fds);
 579               if (worker->read_fd_list == NULL)
 580                 {
 581                   worker->read_fd_list = g_unix_fd_list_new_from_array (fds, num_fds);
 582                 }
 583               else
 584                 {
 585                   gint n;
 586                   for (n = 0; n < num_fds; n++)
 587                     {
 588                       /* TODO: really want a append_steal() */
 589                       g_unix_fd_list_append (worker->read_fd_list, fds[n], NULL);
 590                       (void) g_close (fds[n], NULL);
 591                     }
 592                 }
 593               g_free (fds);
 594             }
 595           else if (G_IS_UNIX_CREDENTIALS_MESSAGE (control_message))
 596             {
 597               /* do nothing */
 598             }
 599 #endif
 600           else
 601             {
 602               if (error == NULL)
 603                 {
 604                   g_set_error (&error,
 605                                G_IO_ERROR,
 606                                G_IO_ERROR_FAILED,
 607                                "Unexpected ancillary message of type %s received from peer",
 608                                g_type_name (G_TYPE_FROM_INSTANCE (control_message)));
 609                   _g_dbus_worker_emit_disconnected (worker, TRUE, error);
 610                   g_error_free (error);
 611                   g_object_unref (control_message);
 612                   n++;
 613                   while (n < worker->read_num_ancillary_messages)
 614                     g_object_unref (worker->read_ancillary_messages[n++]);
 615                   g_free (worker->read_ancillary_messages);
 616                   goto out;
 617                 }
 618             }
 619           g_object_unref (control_message);
 620         }
 621       g_free (worker->read_ancillary_messages);
 622     }
 623
 624   if (bytes_read == -1)
 625     {
 626       if (G_UNLIKELY (_g_dbus_debug_transport ()))
 627         {
 628           _g_dbus_debug_print_lock ();
 629           g_print ("========================================================================\n"
 630                    "GDBus-debug:Transport:\n"
 631                    "  ---- READ ERROR on stream of type %s:\n"
 632                    "  ---- %s %d: %s\n",
 633                    g_type_name (G_TYPE_FROM_INSTANCE (g_io_stream_get_input_stream (worker->stream))),
 634                    g_quark_to_string (error->domain), error->code,
 635                    error->message);
 636           _g_dbus_debug_print_unlock ();
 637         }
 638
 639       /* Every async read that uses this callback uses worker->cancellable
 640        * as its GCancellable. worker->cancellable gets cancelled if and only
 641        * if the GDBusConnection tells us to close (either via
 642        * _g_dbus_worker_stop, which is called on last-unref, or directly),
 643        * so a cancelled read must mean our connection was closed locally.
 644        *
 645        * If we're closing, other errors are possible - notably,
 646        * G_IO_ERROR_CLOSED can be seen if we close the stream with an async
 647        * read in-flight. It seems sensible to treat all read errors during
 648        * closing as an expected thing that doesn't trip exit-on-close.
 649        *
 650        * Because close_expected can't be set until we get into the worker
 651        * thread, but the cancellable is signalled sooner (from another
 652        * thread), we do still need to check the error.
 653        */
 654       if (worker->close_expected ||
 655           g_error_matches (error, G_IO_ERROR, G_IO_ERROR_CANCELLED))
 656         _g_dbus_worker_emit_disconnected (worker, FALSE, NULL);
 657       else
 658         _g_dbus_worker_emit_disconnected (worker, TRUE, error);
 659
 660       g_error_free (error);
 661       goto out;
 662     }
 663
 664 #if 0
 665   g_debug ("read %d bytes (is_closed=%d blocking=%d condition=0x%02x) stream %p, %p",
 666            (gint) bytes_read,
 667            g_socket_is_closed (g_socket_connection_get_socket (G_SOCKET_CONNECTION (worker->stream))),
 668            g_socket_get_blocking (g_socket_connection_get_socket (G_SOCKET_CONNECTION (worker->stream))),
 669            g_socket_condition_check (g_socket_connection_get_socket (G_SOCKET_CONNECTION (worker->stream)),
 670                                      G_IO_IN | G_IO_OUT | G_IO_HUP),
 671            worker->stream,
 672            worker);
 673 #endif
 674
 675   /* TODO: hmm, hmm... */
 676   if (bytes_read == 0)
 677     {
 678       g_set_error (&error,
 679                    G_IO_ERROR,
 680                    G_IO_ERROR_FAILED,
 681                    "Underlying GIOStream returned 0 bytes on an async read");
 682       _g_dbus_worker_emit_disconnected (worker, TRUE, error);
 683       g_error_free (error);
 684       goto out;
 685     }
 686
 687   read_message_print_transport_debug (bytes_read, worker);
 688
 689   worker->read_buffer_cur_size += bytes_read;
 690   if (worker->read_buffer_bytes_wanted == worker->read_buffer_cur_size)
 691     {
 692       /* OK, got what we asked for! */
 693       if (worker->read_buffer_bytes_wanted == 16)
 694         {
 695           gssize message_len;
 696           /* OK, got the header - determine how many more bytes are needed */
 697           error = NULL;
 698           message_len = g_dbus_message_bytes_needed ((guchar *) worker->read_buffer,
 699                                                      16,
 700                                                      &error);
 701           if (message_len == -1)
 702             {
 703               g_warning ("_g_dbus_worker_do_read_cb: error determining bytes needed: %s", error->message);
 704               _g_dbus_worker_emit_disconnected (worker, FALSE, error);
 705               g_error_free (error);
 706               goto out;
 707             }
 708
 709           worker->read_buffer_bytes_wanted = message_len;
 710           _g_dbus_worker_do_read_unlocked (worker);
 711         }
 712       else
 713         {
 714           GDBusMessage *message;
 715           error = NULL;
 716
 717           /* TODO: use connection->priv->auth to decode the message */
 718
 719           message = g_dbus_message_new_from_blob ((guchar *) worker->read_buffer,
 720                                                   worker->read_buffer_cur_size,
 721                                                   worker->capabilities,
 722                                                   &error);
 723           if (message == NULL)
 724             {
 725               gchar *s;
 726               s = _g_dbus_hexdump (worker->read_buffer, worker->read_buffer_cur_size, 2);
 727               g_warning ("Error decoding D-Bus message of %" G_GSIZE_FORMAT " bytes\n"
 728                          "The error is: %s\n"
 729                          "The payload is as follows:\n"
 730                          "%s\n",
 731                          worker->read_buffer_cur_size,
 732                          error->message,
 733                          s);
 734               g_free (s);
 735               _g_dbus_worker_emit_disconnected (worker, FALSE, error);
 736               g_error_free (error);
 737               goto out;
 738             }
 739
 740 #ifdef G_OS_UNIX
 741           if (worker->read_fd_list != NULL)
 742             {
 743               g_dbus_message_set_unix_fd_list (message, worker->read_fd_list);
 744               g_object_unref (worker->read_fd_list);
 745               worker->read_fd_list = NULL;
 746             }
 747 #endif
 748
 749           if (G_UNLIKELY (_g_dbus_debug_message ()))
 750             {
 751               gchar *s;
 752               _g_dbus_debug_print_lock ();
 753               g_print ("========================================================================\n"
 754                        "GDBus-debug:Message:\n"
 755                        "  <<<< RECEIVED D-Bus message (%" G_GSIZE_FORMAT " bytes)\n",
 756                        worker->read_buffer_cur_size);
 757               s = g_dbus_message_print (message, 2);
 758               g_print ("%s", s);
 759               g_free (s);
 760               if (G_UNLIKELY (_g_dbus_debug_payload ()))
 761                 {
 762                   s = _g_dbus_hexdump (worker->read_buffer, worker->read_buffer_cur_size, 2);
 763                   g_print ("%s\n", s);
 764                   g_free (s);
 765                 }
 766               _g_dbus_debug_print_unlock ();
 767             }
 768
 769           /* yay, got a message, go deliver it */
 770           _g_dbus_worker_queue_or_deliver_received_message (worker, message);
 771
 772           /* start reading another message! */
 773           worker->read_buffer_bytes_wanted = 0;
 774           worker->read_buffer_cur_size = 0;
 775           _g_dbus_worker_do_read_unlocked (worker);
 776         }
 777     }
 778   else
 779     {
 780       /* didn't get all the bytes we requested - so repeat the request... */
 781       _g_dbus_worker_do_read_unlocked (worker);
 782     }
 783
 784  out:
 785   g_mutex_unlock (&worker->read_lock);
 786
 787   /* gives up the reference acquired when calling g_input_stream_read_async() */
 788   _g_dbus_worker_unref (worker);
 789
 790   /* check if there is any pending close */
 791   schedule_pending_close (worker);
 792 }
 793
 794 /* called in private thread shared by all GDBusConnection instances (with read-lock held) */
 795 static void
 796 _g_dbus_worker_do_read_unlocked (GDBusWorker *worker)
 797 {
 798   /* Note that we do need to keep trying to read even if close_expected is
 799    * true, because only failing a read causes us to signal 'closed'.
 800    */
 801
 802   /* if bytes_wanted is zero, it means start reading a message */
 803   if (worker->read_buffer_bytes_wanted == 0)
 804     {
 805       worker->read_buffer_cur_size = 0;
 806       worker->read_buffer_bytes_wanted = 16;
 807     }
 808
 809   /* ensure we have a (big enough) buffer */
 810   if (worker->read_buffer == NULL || worker->read_buffer_bytes_wanted > worker->read_buffer_allocated_size)
 811     {
 812       /* TODO: 4096 is randomly chosen; might want a better chosen default minimum */
 813       worker->read_buffer_allocated_size = MAX (worker->read_buffer_bytes_wanted, 4096);
 814       worker->read_buffer = g_realloc (worker->read_buffer, worker->read_buffer_allocated_size);
 815     }
 816
 817   if (worker->socket == NULL)
 818     g_input_stream_read_async (g_io_stream_get_input_stream (worker->stream),
 819                                worker->read_buffer + worker->read_buffer_cur_size,
 820                                worker->read_buffer_bytes_wanted - worker->read_buffer_cur_size,
 821                                G_PRIORITY_DEFAULT,
 822                                worker->cancellable,
 823                                (GAsyncReadyCallback) _g_dbus_worker_do_read_cb,
 824                                _g_dbus_worker_ref (worker));
 825   else
 826     {
 827       worker->read_ancillary_messages = NULL;
 828       worker->read_num_ancillary_messages = 0;
 829       _g_socket_read_with_control_messages (worker->socket,
 830                                             worker->read_buffer + worker->read_buffer_cur_size,
 831                                             worker->read_buffer_bytes_wanted - worker->read_buffer_cur_size,
 832                                             &worker->read_ancillary_messages,
 833                                             &worker->read_num_ancillary_messages,
 834                                             G_PRIORITY_DEFAULT,
 835                                             worker->cancellable,
 836                                             (GAsyncReadyCallback) _g_dbus_worker_do_read_cb,
 837                                             _g_dbus_worker_ref (worker));
 838     }
 839 }
 840
 841 /* called in private thread shared by all GDBusConnection instances (without read-lock held) */
 842 static gboolean
 843 _g_dbus_worker_do_initial_read (gpointer data)
 844 {
 845   GDBusWorker *worker = data;
 846   g_mutex_lock (&worker->read_lock);
 847   _g_dbus_worker_do_read_unlocked (worker);
 848   g_mutex_unlock (&worker->read_lock);
 849   return FALSE;
 850 }
 851
 852 /* ---------------------------------------------------------------------------------------------------- */
 853
 854 struct _MessageToWriteData
 855 {
 856   GDBusWorker  *worker;
 857   GDBusMessage *message;
 858   gchar        *blob;
 859   gsize         blob_size;
 860
 861   gsize         total_written;
 862   GTask        *task;
 863 };
 864
 865 static void
 866 message_to_write_data_free (MessageToWriteData *data)
 867 {
 868   _g_dbus_worker_unref (data->worker);
 869   if (data->message)
 870     g_object_unref (data->message);
 871   g_free (data->blob);
 872   g_slice_free (MessageToWriteData, data);
 873 }
 874
 875 /* ---------------------------------------------------------------------------------------------------- */
 876
 877 static void write_message_continue_writing (MessageToWriteData *data);
 878
 879 /* called in private thread shared by all GDBusConnection instances
 880  *
 881  * write-lock is not held on entry
 882  * output_pending is PENDING_WRITE on entry
 883  */
 884 static void
 885 write_message_async_cb (GObject      *source_object,
 886                         GAsyncResult *res,
 887                         gpointer      user_data)
 888 {
 889   MessageToWriteData *data = user_data;
 890   GTask *task;
 891   gssize bytes_written;
 892   GError *error;
 893
 894   /* Note: we can't access data->task after calling g_task_return_* () because the
 895    * callback can free @data and we're not completing in idle. So use a copy of the pointer.
 896    */
 897   task = data->task;
 898
 899   error = NULL;
 900   bytes_written = g_output_stream_write_finish (G_OUTPUT_STREAM (source_object),
 901                                                 res,
 902                                                 &error);
 903   if (bytes_written == -1)
 904     {
 905       g_task_return_error (task, error);
 906       g_object_unref (task);
 907       goto out;
 908     }
 909   g_assert (bytes_written > 0); /* zero is never returned */
 910
 911   write_message_print_transport_debug (bytes_written, data);
 912
 913   data->total_written += bytes_written;
 914   g_assert (data->total_written <= data->blob_size);
 915   if (data->total_written == data->blob_size)
 916     {
 917       g_task_return_boolean (task, TRUE);
 918       g_object_unref (task);
 919       goto out;
 920     }
 921
 922   write_message_continue_writing (data);
 923
 924  out:
 925   ;
 926 }
 927
 928 /* called in private thread shared by all GDBusConnection instances
 929  *
 930  * write-lock is not held on entry
 931  * output_pending is PENDING_WRITE on entry
 932  */
 933 #ifdef G_OS_UNIX
 934 static gboolean
 935 on_socket_ready (GSocket      *socket,
 936                  GIOCondition  condition,
 937                  gpointer      user_data)
 938 {
 939   MessageToWriteData *data = user_data;
 940   write_message_continue_writing (data);
 941   return FALSE; /* remove source */
 942 }
 943 #endif
 944
 945 /* called in private thread shared by all GDBusConnection instances
 946  *
 947  * write-lock is not held on entry
 948  * output_pending is PENDING_WRITE on entry
 949  */
 950 static void
 951 write_message_continue_writing (MessageToWriteData *data)
 952 {
 953   GOutputStream *ostream;
 954 #ifdef G_OS_UNIX
 955   GTask *task;
 956   GUnixFDList *fd_list;
 957 #endif
 958
 959 #ifdef G_OS_UNIX
 960   /* Note: we can't access data->task after calling g_task_return_* () because the
 961    * callback can free @data and we're not completing in idle. So use a copy of the pointer.
 962    */
 963   task = data->task;
 964 #endif
 965
 966   ostream = g_io_stream_get_output_stream (data->worker->stream);
 967 #ifdef G_OS_UNIX
 968   fd_list = g_dbus_message_get_unix_fd_list (data->message);
 969 #endif
 970
 971   g_assert (!g_output_stream_has_pending (ostream));
 972   g_assert_cmpint (data->total_written, <, data->blob_size);
 973
 974   if (FALSE)
 975     {
 976     }
 977 #ifdef G_OS_UNIX
 978   else if (G_IS_SOCKET_OUTPUT_STREAM (ostream) && data->total_written == 0)
 979     {
 980       GOutputVector vector;
 981       GSocketControlMessage *control_message;
 982       gssize bytes_written;
 983       GError *error;
 984
 985       vector.buffer = data->blob;
 986       vector.size = data->blob_size;
 987
 988       control_message = NULL;
 989       if (fd_list != NULL && g_unix_fd_list_get_length (fd_list) > 0)
 990         {
 991           if (!(data->worker->capabilities & G_DBUS_CAPABILITY_FLAGS_UNIX_FD_PASSING))
 992             {
 993               g_task_return_new_error (task,
 994                                        G_IO_ERROR,
 995                                        G_IO_ERROR_FAILED,
 996                                        "Tried sending a file descriptor but remote peer does not support this capability");
 997               g_object_unref (task);
 998               goto out;
 999             }
1000           control_message = g_unix_fd_message_new_with_fd_list (fd_list);
1001         }
1002
1003       error = NULL;
1004       bytes_written = g_socket_send_message (data->worker->socket,
1005                                              NULL, /* address */
1006                                              &vector,
1007                                              1,
1008                                              control_message != NULL ? &control_message : NULL,
1009                                              control_message != NULL ? 1 : 0,
1010                                              G_SOCKET_MSG_NONE,
1011                                              data->worker->cancellable,
1012                                              &error);
1013       if (control_message != NULL)
1014         g_object_unref (control_message);
1015
1016       if (bytes_written == -1)
1017         {
1018           /* Handle WOULD_BLOCK by waiting until there's room in the buffer */
1019           if (g_error_matches (error, G_IO_ERROR, G_IO_ERROR_WOULD_BLOCK))
1020             {
1021               GSource *source;
1022               source = g_socket_create_source (data->worker->socket,
1023                                                G_IO_OUT | G_IO_HUP | G_IO_ERR,
1024                                                data->worker->cancellable);
1025               g_source_set_callback (source,
1026                                      (GSourceFunc) on_socket_ready,
1027                                      data,
1028                                      NULL); /* GDestroyNotify */
1029               g_source_attach (source, g_main_context_get_thread_default ());
1030               g_source_unref (source);
1031               g_error_free (error);
1032               goto out;
1033             }
1034           g_task_return_error (task, error);
1035           g_object_unref (task);
1036           goto out;
1037         }
1038       g_assert (bytes_written > 0); /* zero is never returned */
1039
1040       write_message_print_transport_debug (bytes_written, data);
1041
1042       data->total_written += bytes_written;
1043       g_assert (data->total_written <= data->blob_size);
1044       if (data->total_written == data->blob_size)
1045         {
1046           g_task_return_boolean (task, TRUE);
1047           g_object_unref (task);
1048           goto out;
1049         }
1050
1051       write_message_continue_writing (data);
1052     }
1053 #endif
1054   else
1055     {
1056 #ifdef G_OS_UNIX
1057       if (fd_list != NULL)
1058         {
1059           g_task_return_new_error (task,
1060                                    G_IO_ERROR,
1061                                    G_IO_ERROR_FAILED,
1062                                    "Tried sending a file descriptor on unsupported stream of type %s",
1063                                    g_type_name (G_TYPE_FROM_INSTANCE (ostream)));
1064           g_object_unref (task);
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 #ifdef G_OS_UNIX
1078  out:
1079 #endif
1080   ;
1081 }
1082
1083 /* called in private thread shared by all GDBusConnection instances
1084  *
1085  * write-lock is not held on entry
1086  * output_pending is PENDING_WRITE on entry
1087  */
1088 static void
1089 write_message_async (GDBusWorker         *worker,
1090                      MessageToWriteData  *data,
1091                      GAsyncReadyCallback  callback,
1092                      gpointer             user_data)
1093 {
1094   data->task = g_task_new (NULL, NULL, callback, user_data);
1095   g_task_set_source_tag (data->task, write_message_async);
1096   data->total_written = 0;
1097   write_message_continue_writing (data);
1098 }
1099
1100 /* called in private thread shared by all GDBusConnection instances (with write-lock held) */
1101 static gboolean
1102 write_message_finish (GAsyncResult   *res,
1103                       GError        **error)
1104 {
1105   g_return_val_if_fail (g_task_is_valid (res, NULL), FALSE);
1106
1107   return g_task_propagate_boolean (G_TASK (res), error);
1108 }
1109 /* ---------------------------------------------------------------------------------------------------- */
1110
1111 static void continue_writing (GDBusWorker *worker);
1112
1113 typedef struct
1114 {
1115   GDBusWorker *worker;
1116   GList *flushers;
1117 } FlushAsyncData;
1118
1119 static void
1120 flush_data_list_complete (const GList  *flushers,
1121                           const GError *error)
1122 {
1123   const GList *l;
1124
1125   for (l = flushers; l != NULL; l = l->next)
1126     {
1127       FlushData *f = l->data;
1128
1129       f->error = error != NULL ? g_error_copy (error) : NULL;
1130
1131       g_mutex_lock (&f->mutex);
1132       g_cond_signal (&f->cond);
1133       g_mutex_unlock (&f->mutex);
1134     }
1135 }
1136
1137 /* called in private thread shared by all GDBusConnection instances
1138  *
1139  * write-lock is not held on entry
1140  * output_pending is PENDING_FLUSH on entry
1141  */
1142 static void
1143 ostream_flush_cb (GObject      *source_object,
1144                   GAsyncResult *res,
1145                   gpointer      user_data)
1146 {
1147   FlushAsyncData *data = user_data;
1148   GError *error;
1149
1150   error = NULL;
1151   g_output_stream_flush_finish (G_OUTPUT_STREAM (source_object),
1152                                 res,
1153                                 &error);
1154
1155   if (error == NULL)
1156     {
1157       if (G_UNLIKELY (_g_dbus_debug_transport ()))
1158         {
1159           _g_dbus_debug_print_lock ();
1160           g_print ("========================================================================\n"
1161                    "GDBus-debug:Transport:\n"
1162                    "  ---- FLUSHED stream of type %s\n",
1163                    g_type_name (G_TYPE_FROM_INSTANCE (g_io_stream_get_output_stream (data->worker->stream))));
1164           _g_dbus_debug_print_unlock ();
1165         }
1166     }
1167
1168   g_assert (data->flushers != NULL);
1169   flush_data_list_complete (data->flushers, error);
1170   g_list_free (data->flushers);
1171
1172   if (error != NULL)
1173     g_error_free (error);
1174
1175   /* Make sure we tell folks that we don't have additional
1176      flushes pending */
1177   g_mutex_lock (&data->worker->write_lock);
1178   data->worker->write_num_messages_flushed = data->worker->write_num_messages_written;
1179   g_assert (data->worker->output_pending == PENDING_FLUSH);
1180   data->worker->output_pending = PENDING_NONE;
1181   g_mutex_unlock (&data->worker->write_lock);
1182
1183   /* OK, cool, finally kick off the next write */
1184   continue_writing (data->worker);
1185
1186   _g_dbus_worker_unref (data->worker);
1187   g_free (data);
1188 }
1189
1190 /* called in private thread shared by all GDBusConnection instances
1191  *
1192  * write-lock is not held on entry
1193  * output_pending is PENDING_FLUSH on entry
1194  */
1195 static void
1196 start_flush (FlushAsyncData *data)
1197 {
1198   g_output_stream_flush_async (g_io_stream_get_output_stream (data->worker->stream),
1199                                G_PRIORITY_DEFAULT,
1200                                data->worker->cancellable,
1201                                ostream_flush_cb,
1202                                data);
1203 }
1204
1205 /* called in private thread shared by all GDBusConnection instances
1206  *
1207  * write-lock is held on entry
1208  * output_pending is PENDING_NONE on entry
1209  */
1210 static void
1211 message_written_unlocked (GDBusWorker *worker,
1212                           MessageToWriteData *message_data)
1213 {
1214   if (G_UNLIKELY (_g_dbus_debug_message ()))
1215     {
1216       gchar *s;
1217       _g_dbus_debug_print_lock ();
1218       g_print ("========================================================================\n"
1219                "GDBus-debug:Message:\n"
1220                "  >>>> SENT D-Bus message (%" G_GSIZE_FORMAT " bytes)\n",
1221                message_data->blob_size);
1222       s = g_dbus_message_print (message_data->message, 2);
1223       g_print ("%s", s);
1224       g_free (s);
1225       if (G_UNLIKELY (_g_dbus_debug_payload ()))
1226         {
1227           s = _g_dbus_hexdump (message_data->blob, message_data->blob_size, 2);
1228           g_print ("%s\n", s);
1229           g_free (s);
1230         }
1231       _g_dbus_debug_print_unlock ();
1232     }
1233
1234   worker->write_num_messages_written += 1;
1235 }
1236
1237 /* called in private thread shared by all GDBusConnection instances
1238  *
1239  * write-lock is held on entry
1240  * output_pending is PENDING_NONE on entry
1241  *
1242  * Returns: non-%NULL, setting @output_pending, if we need to flush now
1243  */
1244 static FlushAsyncData *
1245 prepare_flush_unlocked (GDBusWorker *worker)
1246 {
1247   GList *l;
1248   GList *ll;
1249   GList *flushers;
1250
1251   flushers = NULL;
1252   for (l = worker->write_pending_flushes; l != NULL; l = ll)
1253     {
1254       FlushData *f = l->data;
1255       ll = l->next;
1256
1257       if (f->number_to_wait_for == worker->write_num_messages_written)
1258         {
1259           flushers = g_list_append (flushers, f);
1260           worker->write_pending_flushes = g_list_delete_link (worker->write_pending_flushes, l);
1261         }
1262     }
1263   if (flushers != NULL)
1264     {
1265       g_assert (worker->output_pending == PENDING_NONE);
1266       worker->output_pending = PENDING_FLUSH;
1267     }
1268
1269   if (flushers != NULL)
1270     {
1271       FlushAsyncData *data;
1272
1273       data = g_new0 (FlushAsyncData, 1);
1274       data->worker = _g_dbus_worker_ref (worker);
1275       data->flushers = flushers;
1276       return data;
1277     }
1278
1279   return NULL;
1280 }
1281
1282 /* called in private thread shared by all GDBusConnection instances
1283  *
1284  * write-lock is not held on entry
1285  * output_pending is PENDING_WRITE on entry
1286  */
1287 static void
1288 write_message_cb (GObject       *source_object,
1289                   GAsyncResult  *res,
1290                   gpointer       user_data)
1291 {
1292   MessageToWriteData *data = user_data;
1293   GError *error;
1294
1295   g_mutex_lock (&data->worker->write_lock);
1296   g_assert (data->worker->output_pending == PENDING_WRITE);
1297   data->worker->output_pending = PENDING_NONE;
1298
1299   error = NULL;
1300   if (!write_message_finish (res, &error))
1301     {
1302       g_mutex_unlock (&data->worker->write_lock);
1303
1304       /* TODO: handle */
1305       _g_dbus_worker_emit_disconnected (data->worker, TRUE, error);
1306       g_error_free (error);
1307
1308       g_mutex_lock (&data->worker->write_lock);
1309     }
1310
1311   message_written_unlocked (data->worker, data);
1312
1313   g_mutex_unlock (&data->worker->write_lock);
1314
1315   continue_writing (data->worker);
1316
1317   message_to_write_data_free (data);
1318 }
1319
1320 /* called in private thread shared by all GDBusConnection instances
1321  *
1322  * write-lock is not held on entry
1323  * output_pending is PENDING_CLOSE on entry
1324  */
1325 static void
1326 iostream_close_cb (GObject      *source_object,
1327                    GAsyncResult *res,
1328                    gpointer      user_data)
1329 {
1330   GDBusWorker *worker = user_data;
1331   GError *error = NULL;
1332   GList *pending_close_attempts, *pending_flush_attempts;
1333   GQueue *send_queue;
1334
1335   g_io_stream_close_finish (worker->stream, res, &error);
1336
1337   g_mutex_lock (&worker->write_lock);
1338
1339   pending_close_attempts = worker->pending_close_attempts;
1340   worker->pending_close_attempts = NULL;
1341
1342   pending_flush_attempts = worker->write_pending_flushes;
1343   worker->write_pending_flushes = NULL;
1344
1345   send_queue = worker->write_queue;
1346   worker->write_queue = g_queue_new ();
1347
1348   g_assert (worker->output_pending == PENDING_CLOSE);
1349   worker->output_pending = PENDING_NONE;
1350
1351   g_mutex_unlock (&worker->write_lock);
1352
1353   while (pending_close_attempts != NULL)
1354     {
1355       CloseData *close_data = pending_close_attempts->data;
1356
1357       pending_close_attempts = g_list_delete_link (pending_close_attempts,
1358                                                    pending_close_attempts);
1359
1360       if (close_data->task != NULL)
1361         {
1362           if (error != NULL)
1363             g_task_return_error (close_data->task, g_error_copy (error));
1364           else
1365             g_task_return_boolean (close_data->task, TRUE);
1366         }
1367
1368       close_data_free (close_data);
1369     }
1370
1371   g_clear_error (&error);
1372
1373   /* all messages queued for sending are discarded */
1374   g_queue_free_full (send_queue, (GDestroyNotify) message_to_write_data_free);
1375   /* all queued flushes fail */
1376   error = g_error_new (G_IO_ERROR, G_IO_ERROR_CANCELLED,
1377                        _("Operation was cancelled"));
1378   flush_data_list_complete (pending_flush_attempts, error);
1379   g_list_free (pending_flush_attempts);
1380   g_clear_error (&error);
1381
1382   _g_dbus_worker_unref (worker);
1383 }
1384
1385 /* called in private thread shared by all GDBusConnection instances
1386  *
1387  * write-lock is not held on entry
1388  * output_pending must be PENDING_NONE on entry
1389  */
1390 static void
1391 continue_writing (GDBusWorker *worker)
1392 {
1393   MessageToWriteData *data;
1394   FlushAsyncData *flush_async_data;
1395
1396  write_next:
1397   /* we mustn't try to write two things at once */
1398   g_assert (worker->output_pending == PENDING_NONE);
1399
1400   g_mutex_lock (&worker->write_lock);
1401
1402   data = NULL;
1403   flush_async_data = NULL;
1404
1405   /* if we want to close the connection, that takes precedence */
1406   if (worker->pending_close_attempts != NULL)
1407     {
1408       GInputStream *input = g_io_stream_get_input_stream (worker->stream);
1409
1410       if (!g_input_stream_has_pending (input))
1411         {
1412           worker->close_expected = TRUE;
1413           worker->output_pending = PENDING_CLOSE;
1414
1415           g_io_stream_close_async (worker->stream, G_PRIORITY_DEFAULT,
1416                                    NULL, iostream_close_cb,
1417                                    _g_dbus_worker_ref (worker));
1418         }
1419     }
1420   else
1421     {
1422       flush_async_data = prepare_flush_unlocked (worker);
1423
1424       if (flush_async_data == NULL)
1425         {
1426           data = g_queue_pop_head (worker->write_queue);
1427
1428           if (data != NULL)
1429             worker->output_pending = PENDING_WRITE;
1430         }
1431     }
1432
1433   g_mutex_unlock (&worker->write_lock);
1434
1435   /* Note that write_lock is only used for protecting the @write_queue
1436    * and @output_pending fields of the GDBusWorker struct ... which we
1437    * need to modify from arbitrary threads in _g_dbus_worker_send_message().
1438    *
1439    * Therefore, it's fine to drop it here when calling back into user
1440    * code and then writing the message out onto the GIOStream since this
1441    * function only runs on the worker thread.
1442    */
1443
1444   if (flush_async_data != NULL)
1445     {
1446       start_flush (flush_async_data);
1447       g_assert (data == NULL);
1448     }
1449   else if (data != NULL)
1450     {
1451       GDBusMessage *old_message;
1452       guchar *new_blob;
1453       gsize new_blob_size;
1454       GError *error;
1455
1456       old_message = data->message;
1457       data->message = _g_dbus_worker_emit_message_about_to_be_sent (worker, data->message);
1458       if (data->message == old_message)
1459         {
1460           /* filters had no effect - do nothing */
1461         }
1462       else if (data->message == NULL)
1463         {
1464           /* filters dropped message */
1465           g_mutex_lock (&worker->write_lock);
1466           worker->output_pending = PENDING_NONE;
1467           g_mutex_unlock (&worker->write_lock);
1468           message_to_write_data_free (data);
1469           goto write_next;
1470         }
1471       else
1472         {
1473           /* filters altered the message -> reencode */
1474           error = NULL;
1475           new_blob = g_dbus_message_to_blob (data->message,
1476                                              &new_blob_size,
1477                                              worker->capabilities,
1478                                              &error);
1479           if (new_blob == NULL)
1480             {
1481               /* if filter make the GDBusMessage unencodeable, just complain on stderr and send
1482                * the old message instead
1483                */
1484               g_warning ("Error encoding GDBusMessage with serial %d altered by filter function: %s",
1485                          g_dbus_message_get_serial (data->message),
1486                          error->message);
1487               g_error_free (error);
1488             }
1489           else
1490             {
1491               g_free (data->blob);
1492               data->blob = (gchar *) new_blob;
1493               data->blob_size = new_blob_size;
1494             }
1495         }
1496
1497       write_message_async (worker,
1498                            data,
1499                            write_message_cb,
1500                            data);
1501     }
1502 }
1503
1504 /* called in private thread shared by all GDBusConnection instances
1505  *
1506  * write-lock is not held on entry
1507  * output_pending may be anything
1508  */
1509 static gboolean
1510 continue_writing_in_idle_cb (gpointer user_data)
1511 {
1512   GDBusWorker *worker = user_data;
1513
1514   /* Because this is the worker thread, we can read this struct member
1515    * without holding the lock: no other thread ever modifies it.
1516    */
1517   if (worker->output_pending == PENDING_NONE)
1518     continue_writing (worker);
1519
1520   return FALSE;
1521 }
1522
1523 /*
1524  * @write_data: (transfer full) (nullable):
1525  * @flush_data: (transfer full) (nullable):
1526  * @close_data: (transfer full) (nullable):
1527  *
1528  * Can be called from any thread
1529  *
1530  * write_lock is held on entry
1531  * output_pending may be anything
1532  */
1533 static void
1534 schedule_writing_unlocked (GDBusWorker        *worker,
1535                            MessageToWriteData *write_data,
1536                            FlushData          *flush_data,
1537                            CloseData          *close_data)
1538 {
1539   if (write_data != NULL)
1540     g_queue_push_tail (worker->write_queue, write_data);
1541
1542   if (flush_data != NULL)
1543     worker->write_pending_flushes = g_list_prepend (worker->write_pending_flushes, flush_data);
1544
1545   if (close_data != NULL)
1546     worker->pending_close_attempts = g_list_prepend (worker->pending_close_attempts,
1547                                                      close_data);
1548
1549   /* If we had output pending, the next bit of output will happen
1550    * automatically when it finishes, so we only need to do this
1551    * if nothing was pending.
1552    *
1553    * The idle callback will re-check that output_pending is still
1554    * PENDING_NONE, to guard against output starting before the idle.
1555    */
1556   if (worker->output_pending == PENDING_NONE)
1557     {
1558       GSource *idle_source;
1559       idle_source = g_idle_source_new ();
1560       g_source_set_priority (idle_source, G_PRIORITY_DEFAULT);
1561       g_source_set_callback (idle_source,
1562                              continue_writing_in_idle_cb,
1563                              _g_dbus_worker_ref (worker),
1564                              (GDestroyNotify) _g_dbus_worker_unref);
1565       g_source_set_name (idle_source, "[gio] continue_writing_in_idle_cb");
1566       g_source_attach (idle_source, worker->shared_thread_data->context);
1567       g_source_unref (idle_source);
1568     }
1569 }
1570
1571 static void
1572 schedule_pending_close (GDBusWorker *worker)
1573 {
1574   g_mutex_lock (&worker->write_lock);
1575   if (worker->pending_close_attempts)
1576     schedule_writing_unlocked (worker, NULL, NULL, NULL);
1577   g_mutex_unlock (&worker->write_lock);
1578 }
1579
1580 /* ---------------------------------------------------------------------------------------------------- */
1581
1582 /* can be called from any thread - steals blob
1583  *
1584  * write_lock is not held on entry
1585  * output_pending may be anything
1586  */
1587 void
1588 _g_dbus_worker_send_message (GDBusWorker    *worker,
1589                              GDBusMessage   *message,
1590                              gchar          *blob,
1591                              gsize           blob_len)
1592 {
1593   MessageToWriteData *data;
1594
1595   g_return_if_fail (G_IS_DBUS_MESSAGE (message));
1596   g_return_if_fail (blob != NULL);
1597   g_return_if_fail (blob_len > 16);
1598
1599   data = g_slice_new0 (MessageToWriteData);
1600   data->worker = _g_dbus_worker_ref (worker);
1601   data->message = g_object_ref (message);
1602   data->blob = blob; /* steal! */
1603   data->blob_size = blob_len;
1604
1605   g_mutex_lock (&worker->write_lock);
1606   schedule_writing_unlocked (worker, data, NULL, NULL);
1607   g_mutex_unlock (&worker->write_lock);
1608 }
1609
1610 /* ---------------------------------------------------------------------------------------------------- */
1611
1612 GDBusWorker *
1613 _g_dbus_worker_new (GIOStream                              *stream,
1614                     GDBusCapabilityFlags                    capabilities,
1615                     gboolean                                initially_frozen,
1616                     GDBusWorkerMessageReceivedCallback      message_received_callback,
1617                     GDBusWorkerMessageAboutToBeSentCallback message_about_to_be_sent_callback,
1618                     GDBusWorkerDisconnectedCallback         disconnected_callback,
1619                     gpointer                                user_data)
1620 {
1621   GDBusWorker *worker;
1622   GSource *idle_source;
1623
1624   g_return_val_if_fail (G_IS_IO_STREAM (stream), NULL);
1625   g_return_val_if_fail (message_received_callback != NULL, NULL);
1626   g_return_val_if_fail (message_about_to_be_sent_callback != NULL, NULL);
1627   g_return_val_if_fail (disconnected_callback != NULL, NULL);
1628
1629   worker = g_new0 (GDBusWorker, 1);
1630   worker->ref_count = 1;
1631
1632   g_mutex_init (&worker->read_lock);
1633   worker->message_received_callback = message_received_callback;
1634   worker->message_about_to_be_sent_callback = message_about_to_be_sent_callback;
1635   worker->disconnected_callback = disconnected_callback;
1636   worker->user_data = user_data;
1637   worker->stream = g_object_ref (stream);
1638   worker->capabilities = capabilities;
1639   worker->cancellable = g_cancellable_new ();
1640   worker->output_pending = PENDING_NONE;
1641
1642   worker->frozen = initially_frozen;
1643   worker->received_messages_while_frozen = g_queue_new ();
1644
1645   g_mutex_init (&worker->write_lock);
1646   worker->write_queue = g_queue_new ();
1647
1648   if (G_IS_SOCKET_CONNECTION (worker->stream))
1649     worker->socket = g_socket_connection_get_socket (G_SOCKET_CONNECTION (worker->stream));
1650
1651   worker->shared_thread_data = _g_dbus_shared_thread_ref ();
1652
1653   /* begin reading */
1654   idle_source = g_idle_source_new ();
1655   g_source_set_priority (idle_source, G_PRIORITY_DEFAULT);
1656   g_source_set_callback (idle_source,
1657                          _g_dbus_worker_do_initial_read,
1658                          _g_dbus_worker_ref (worker),
1659                          (GDestroyNotify) _g_dbus_worker_unref);
1660   g_source_set_name (idle_source, "[gio] _g_dbus_worker_do_initial_read");
1661   g_source_attach (idle_source, worker->shared_thread_data->context);
1662   g_source_unref (idle_source);
1663
1664   return worker;
1665 }
1666
1667 /* ---------------------------------------------------------------------------------------------------- */
1668
1669 /* can be called from any thread
1670  *
1671  * write_lock is not held on entry
1672  * output_pending may be anything
1673  */
1674 void
1675 _g_dbus_worker_close (GDBusWorker         *worker,
1676                       GTask               *task)
1677 {
1678   CloseData *close_data;
1679
1680   close_data = g_slice_new0 (CloseData);
1681   close_data->worker = _g_dbus_worker_ref (worker);
1682   close_data->task = (task == NULL ? NULL : g_object_ref (task));
1683
1684   /* Don't set worker->close_expected here - we're in the wrong thread.
1685    * It'll be set before the actual close happens.
1686    */
1687   g_cancellable_cancel (worker->cancellable);
1688   g_mutex_lock (&worker->write_lock);
1689   schedule_writing_unlocked (worker, NULL, NULL, close_data);
1690   g_mutex_unlock (&worker->write_lock);
1691 }
1692
1693 /* This can be called from any thread - frees worker. Note that
1694  * callbacks might still happen if called from another thread than the
1695  * worker - use your own synchronization primitive in the callbacks.
1696  *
1697  * write_lock is not held on entry
1698  * output_pending may be anything
1699  */
1700 void
1701 _g_dbus_worker_stop (GDBusWorker *worker)
1702 {
1703   g_atomic_int_set (&worker->stopped, TRUE);
1704
1705   /* Cancel any pending operations and schedule a close of the underlying I/O
1706    * stream in the worker thread
1707    */
1708   _g_dbus_worker_close (worker, NULL);
1709
1710   /* _g_dbus_worker_close holds a ref until after an idle in the worker
1711    * thread has run, so we no longer need to unref in an idle like in
1712    * commit 322e25b535
1713    */
1714   _g_dbus_worker_unref (worker);
1715 }
1716
1717 /* ---------------------------------------------------------------------------------------------------- */
1718
1719 /* can be called from any thread (except the worker thread) - blocks
1720  * calling thread until all queued outgoing messages are written and
1721  * the transport has been flushed
1722  *
1723  * write_lock is not held on entry
1724  * output_pending may be anything
1725  */
1726 gboolean
1727 _g_dbus_worker_flush_sync (GDBusWorker    *worker,
1728                            GCancellable   *cancellable,
1729                            GError        **error)
1730 {
1731   gboolean ret;
1732   FlushData *data;
1733   guint64 pending_writes;
1734
1735   data = NULL;
1736   ret = TRUE;
1737
1738   g_mutex_lock (&worker->write_lock);
1739
1740   /* if the queue is empty, no write is in-flight and we haven't written
1741    * anything since the last flush, then there's nothing to wait for
1742    */
1743   pending_writes = g_queue_get_length (worker->write_queue);
1744
1745   /* if a write is in-flight, we shouldn't be satisfied until the first
1746    * flush operation that follows it
1747    */
1748   if (worker->output_pending == PENDING_WRITE)
1749     pending_writes += 1;
1750
1751   if (pending_writes > 0 ||
1752       worker->write_num_messages_written != worker->write_num_messages_flushed)
1753     {
1754       data = g_new0 (FlushData, 1);
1755       g_mutex_init (&data->mutex);
1756       g_cond_init (&data->cond);
1757       data->number_to_wait_for = worker->write_num_messages_written + pending_writes;
1758       g_mutex_lock (&data->mutex);
1759
1760       schedule_writing_unlocked (worker, NULL, data, NULL);
1761     }
1762   g_mutex_unlock (&worker->write_lock);
1763
1764   if (data != NULL)
1765     {
1766       g_cond_wait (&data->cond, &data->mutex);
1767       g_mutex_unlock (&data->mutex);
1768
1769       /* note:the element is removed from worker->write_pending_flushes in flush_cb() above */
1770       g_cond_clear (&data->cond);
1771       g_mutex_clear (&data->mutex);
1772       if (data->error != NULL)
1773         {
1774           ret = FALSE;
1775           g_propagate_error (error, data->error);
1776         }
1777       g_free (data);
1778     }
1779
1780   return ret;
1781 }
1782
1783 /* ---------------------------------------------------------------------------------------------------- */
1784
1785 #define G_DBUS_DEBUG_AUTHENTICATION (1<<0)
1786 #define G_DBUS_DEBUG_TRANSPORT      (1<<1)
1787 #define G_DBUS_DEBUG_MESSAGE        (1<<2)
1788 #define G_DBUS_DEBUG_PAYLOAD        (1<<3)
1789 #define G_DBUS_DEBUG_CALL           (1<<4)
1790 #define G_DBUS_DEBUG_SIGNAL         (1<<5)
1791 #define G_DBUS_DEBUG_INCOMING       (1<<6)
1792 #define G_DBUS_DEBUG_RETURN         (1<<7)
1793 #define G_DBUS_DEBUG_EMISSION       (1<<8)
1794 #define G_DBUS_DEBUG_ADDRESS        (1<<9)
1795
1796 static gint _gdbus_debug_flags = 0;
1797
1798 gboolean
1799 _g_dbus_debug_authentication (void)
1800 {
1801   _g_dbus_initialize ();
1802   return (_gdbus_debug_flags & G_DBUS_DEBUG_AUTHENTICATION) != 0;
1803 }
1804
1805 gboolean
1806 _g_dbus_debug_transport (void)
1807 {
1808   _g_dbus_initialize ();
1809   return (_gdbus_debug_flags & G_DBUS_DEBUG_TRANSPORT) != 0;
1810 }
1811
1812 gboolean
1813 _g_dbus_debug_message (void)
1814 {
1815   _g_dbus_initialize ();
1816   return (_gdbus_debug_flags & G_DBUS_DEBUG_MESSAGE) != 0;
1817 }
1818
1819 gboolean
1820 _g_dbus_debug_payload (void)
1821 {
1822   _g_dbus_initialize ();
1823   return (_gdbus_debug_flags & G_DBUS_DEBUG_PAYLOAD) != 0;
1824 }
1825
1826 gboolean
1827 _g_dbus_debug_call (void)
1828 {
1829   _g_dbus_initialize ();
1830   return (_gdbus_debug_flags & G_DBUS_DEBUG_CALL) != 0;
1831 }
1832
1833 gboolean
1834 _g_dbus_debug_signal (void)
1835 {
1836   _g_dbus_initialize ();
1837   return (_gdbus_debug_flags & G_DBUS_DEBUG_SIGNAL) != 0;
1838 }
1839
1840 gboolean
1841 _g_dbus_debug_incoming (void)
1842 {
1843   _g_dbus_initialize ();
1844   return (_gdbus_debug_flags & G_DBUS_DEBUG_INCOMING) != 0;
1845 }
1846
1847 gboolean
1848 _g_dbus_debug_return (void)
1849 {
1850   _g_dbus_initialize ();
1851   return (_gdbus_debug_flags & G_DBUS_DEBUG_RETURN) != 0;
1852 }
1853
1854 gboolean
1855 _g_dbus_debug_emission (void)
1856 {
1857   _g_dbus_initialize ();
1858   return (_gdbus_debug_flags & G_DBUS_DEBUG_EMISSION) != 0;
1859 }
1860
1861 gboolean
1862 _g_dbus_debug_address (void)
1863 {
1864   _g_dbus_initialize ();
1865   return (_gdbus_debug_flags & G_DBUS_DEBUG_ADDRESS) != 0;
1866 }
1867
1868 G_LOCK_DEFINE_STATIC (print_lock);
1869
1870 void
1871 _g_dbus_debug_print_lock (void)
1872 {
1873   G_LOCK (print_lock);
1874 }
1875
1876 void
1877 _g_dbus_debug_print_unlock (void)
1878 {
1879   G_UNLOCK (print_lock);
1880 }
1881
1882 /**
1883  * _g_dbus_initialize:
1884  *
1885  * Does various one-time init things such as
1886  *
1887  *  - registering the G_DBUS_ERROR error domain
1888  *  - parses the G_DBUS_DEBUG environment variable
1889  */
1890 void
1891 _g_dbus_initialize (void)
1892 {
1893   static volatile gsize initialized = 0;
1894
1895   if (g_once_init_enter (&initialized))
1896     {
1897       volatile GQuark g_dbus_error_domain;
1898       const gchar *debug;
1899
1900       g_dbus_error_domain = G_DBUS_ERROR;
1901       (g_dbus_error_domain); /* To avoid -Wunused-but-set-variable */
1902
1903       debug = g_getenv ("G_DBUS_DEBUG");
1904       if (debug != NULL)
1905         {
1906           const GDebugKey keys[] = {
1907             { "authentication", G_DBUS_DEBUG_AUTHENTICATION },
1908             { "transport",      G_DBUS_DEBUG_TRANSPORT      },
1909             { "message",        G_DBUS_DEBUG_MESSAGE        },
1910             { "payload",        G_DBUS_DEBUG_PAYLOAD        },
1911             { "call",           G_DBUS_DEBUG_CALL           },
1912             { "signal",         G_DBUS_DEBUG_SIGNAL         },
1913             { "incoming",       G_DBUS_DEBUG_INCOMING       },
1914             { "return",         G_DBUS_DEBUG_RETURN         },
1915             { "emission",       G_DBUS_DEBUG_EMISSION       },
1916             { "address",        G_DBUS_DEBUG_ADDRESS        }
1917           };
1918
1919           _gdbus_debug_flags = g_parse_debug_string (debug, keys, G_N_ELEMENTS (keys));
1920           if (_gdbus_debug_flags & G_DBUS_DEBUG_PAYLOAD)
1921             _gdbus_debug_flags |= G_DBUS_DEBUG_MESSAGE;
1922         }
1923
1924       g_once_init_leave (&initialized, 1);
1925     }
1926 }
1927
1928 /* ---------------------------------------------------------------------------------------------------- */
1929
1930 GVariantType *
1931 _g_dbus_compute_complete_signature (GDBusArgInfo **args)
1932 {
1933   const GVariantType *arg_types[256];
1934   guint n;
1935
1936   if (args)
1937     for (n = 0; args[n] != NULL; n++)
1938       {
1939         /* DBus places a hard limit of 255 on signature length.
1940          * therefore number of args must be less than 256.
1941          */
1942         g_assert (n < 256);
1943
1944         arg_types[n] = G_VARIANT_TYPE (args[n]->signature);
1945
1946         if G_UNLIKELY (arg_types[n] == NULL)
1947           return NULL;
1948       }
1949   else
1950     n = 0;
1951
1952   return g_variant_type_new_tuple (arg_types, n);
1953 }
1954
1955 /* ---------------------------------------------------------------------------------------------------- */
1956
1957 #ifdef G_OS_WIN32
1958
1959 extern BOOL WINAPI ConvertSidToStringSidA (PSID Sid, LPSTR *StringSid);
1960
1961 gchar *
1962 _g_dbus_win32_get_user_sid (void)
1963 {
1964   HANDLE h;
1965   TOKEN_USER *user;
1966   DWORD token_information_len;
1967   PSID psid;
1968   gchar *sid;
1969   gchar *ret;
1970
1971   ret = NULL;
1972   user = NULL;
1973   h = INVALID_HANDLE_VALUE;
1974
1975   if (!OpenProcessToken (GetCurrentProcess (), TOKEN_QUERY, &h))
1976     {
1977       g_warning ("OpenProcessToken failed with error code %d", (gint) GetLastError ());
1978       goto out;
1979     }
1980
1981   /* Get length of buffer */
1982   token_information_len = 0;
1983   if (!GetTokenInformation (h, TokenUser, NULL, 0, &token_information_len))
1984     {
1985       if (GetLastError () != ERROR_INSUFFICIENT_BUFFER)
1986         {
1987           g_warning ("GetTokenInformation() failed with error code %d", (gint) GetLastError ());
1988           goto out;
1989         }
1990     }
1991   user = g_malloc (token_information_len);
1992   if (!GetTokenInformation (h, TokenUser, user, token_information_len, &token_information_len))
1993     {
1994       g_warning ("GetTokenInformation() failed with error code %d", (gint) GetLastError ());
1995       goto out;
1996     }
1997
1998   psid = user->User.Sid;
1999   if (!IsValidSid (psid))
2000     {
2001       g_warning ("Invalid SID");
2002       goto out;
2003     }
2004
2005   if (!ConvertSidToStringSidA (psid, &sid))
2006     {
2007       g_warning ("Invalid SID");
2008       goto out;
2009     }
2010
2011   ret = g_strdup (sid);
2012   LocalFree (sid);
2013
2014 out:
2015   g_free (user);
2016   if (h != INVALID_HANDLE_VALUE)
2017     CloseHandle (h);
2018   return ret;
2019 }
2020 #endif
2021
2022 /* ---------------------------------------------------------------------------------------------------- */
2023
2024 gchar *
2025 _g_dbus_get_machine_id (GError **error)
2026 {
2027 #ifdef G_OS_WIN32
2028   HW_PROFILE_INFOA info;
2029   char *src, *dest, *res;
2030   int i;
2031
2032   if (!GetCurrentHwProfileA (&info))
2033     {
2034       char *message = g_win32_error_message (GetLastError ());
2035       g_set_error (error,
2036                    G_IO_ERROR,
2037                    G_IO_ERROR_FAILED,
2038                    _("Unable to get Hardware profile: %s"), message);
2039       g_free (message);
2040       return NULL;
2041     }
2042
2043   /* Form: {12340001-4980-1920-6788-123456789012} */
2044   src = &info.szHwProfileGuid[0];
2045
2046   res = g_malloc (32+1);
2047   dest = res;
2048
2049   src++; /* Skip { */
2050   for (i = 0; i < 8; i++)
2051     *dest++ = *src++;
2052   src++; /* Skip - */
2053   for (i = 0; i < 4; i++)
2054     *dest++ = *src++;
2055   src++; /* Skip - */
2056   for (i = 0; i < 4; i++)
2057     *dest++ = *src++;
2058   src++; /* Skip - */
2059   for (i = 0; i < 4; i++)
2060     *dest++ = *src++;
2061   src++; /* Skip - */
2062   for (i = 0; i < 12; i++)
2063     *dest++ = *src++;
2064   *dest = 0;
2065
2066   return res;
2067 #else
2068   gchar *ret;
2069   GError *first_error;
2070   /* TODO: use PACKAGE_LOCALSTATEDIR ? */
2071   ret = NULL;
2072   first_error = NULL;
2073   if (!g_file_get_contents ("/var/lib/dbus/machine-id",
2074                             &ret,
2075                             NULL,
2076                             &first_error) &&
2077       !g_file_get_contents ("/etc/machine-id",
2078                             &ret,
2079                             NULL,
2080                             NULL))
2081     {
2082       g_propagate_prefixed_error (error, first_error,
2083                                   _("Unable to load /var/lib/dbus/machine-id or /etc/machine-id: "));
2084     }
2085   else
2086     {
2087       /* ignore the error from the first try, if any */
2088       g_clear_error (&first_error);
2089       /* TODO: validate value */
2090       g_strstrip (ret);
2091     }
2092   return ret;
2093 #endif
2094 }
2095
2096 /* ---------------------------------------------------------------------------------------------------- */
2097
2098 gchar *
2099 _g_dbus_enum_to_string (GType enum_type, gint value)
2100 {
2101   gchar *ret;
2102   GEnumClass *klass;
2103   GEnumValue *enum_value;
2104
2105   klass = g_type_class_ref (enum_type);
2106   enum_value = g_enum_get_value (klass, value);
2107   if (enum_value != NULL)
2108     ret = g_strdup (enum_value->value_nick);
2109   else
2110     ret = g_strdup_printf ("unknown (value %d)", value);
2111   g_type_class_unref (klass);
2112   return ret;
2113 }
2114
2115 /* ---------------------------------------------------------------------------------------------------- */
2116
2117 static void
2118 write_message_print_transport_debug (gssize bytes_written,
2119                                      MessageToWriteData *data)
2120 {
2121   if (G_LIKELY (!_g_dbus_debug_transport ()))
2122     goto out;
2123
2124   _g_dbus_debug_print_lock ();
2125   g_print ("========================================================================\n"
2126            "GDBus-debug:Transport:\n"
2127            "  >>>> WROTE %" G_GSSIZE_FORMAT " bytes of message with serial %d and\n"
2128            "       size %" G_GSIZE_FORMAT " from offset %" G_GSIZE_FORMAT " on a %s\n",
2129            bytes_written,
2130            g_dbus_message_get_serial (data->message),
2131            data->blob_size,
2132            data->total_written,
2133            g_type_name (G_TYPE_FROM_INSTANCE (g_io_stream_get_output_stream (data->worker->stream))));
2134   _g_dbus_debug_print_unlock ();
2135  out:
2136   ;
2137 }
2138
2139 /* ---------------------------------------------------------------------------------------------------- */
2140
2141 static void
2142 read_message_print_transport_debug (gssize bytes_read,
2143                                     GDBusWorker *worker)
2144 {
2145   gsize size;
2146   gint32 serial;
2147   gint32 message_length;
2148
2149   if (G_LIKELY (!_g_dbus_debug_transport ()))
2150     goto out;
2151
2152   size = bytes_read + worker->read_buffer_cur_size;
2153   serial = 0;
2154   message_length = 0;
2155   if (size >= 16)
2156     message_length = g_dbus_message_bytes_needed ((guchar *) worker->read_buffer, size, NULL);
2157   if (size >= 1)
2158     {
2159       switch (worker->read_buffer[0])
2160         {
2161         case 'l':
2162           if (size >= 12)
2163             serial = GUINT32_FROM_LE (((guint32 *) worker->read_buffer)[2]);
2164           break;
2165         case 'B':
2166           if (size >= 12)
2167             serial = GUINT32_FROM_BE (((guint32 *) worker->read_buffer)[2]);
2168           break;
2169         default:
2170           /* an error will be set elsewhere if this happens */
2171           goto out;
2172         }
2173     }
2174
2175     _g_dbus_debug_print_lock ();
2176   g_print ("========================================================================\n"
2177            "GDBus-debug:Transport:\n"
2178            "  <<<< READ %" G_GSSIZE_FORMAT " bytes of message with serial %d and\n"
2179            "       size %d to offset %" G_GSIZE_FORMAT " from a %s\n",
2180            bytes_read,
2181            serial,
2182            message_length,
2183            worker->read_buffer_cur_size,
2184            g_type_name (G_TYPE_FROM_INSTANCE (g_io_stream_get_input_stream (worker->stream))));
2185   _g_dbus_debug_print_unlock ();
2186  out:
2187   ;
2188 }
2189
2190 /* ---------------------------------------------------------------------------------------------------- */
2191
2192 gboolean
2193 _g_signal_accumulator_false_handled (GSignalInvocationHint *ihint,
2194                                      GValue                *return_accu,
2195                                      const GValue          *handler_return,
2196                                      gpointer               dummy)
2197 {
2198   gboolean continue_emission;
2199   gboolean signal_return;
2200
2201   signal_return = g_value_get_boolean (handler_return);
2202   g_value_set_boolean (return_accu, signal_return);
2203   continue_emission = signal_return;
2204
2205   return continue_emission;
2206 }