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