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 "giostream.h"
  41 #include "gsocketcontrolmessage.h"
  42 #include "gsocketconnection.h"
  43
  44 #ifdef G_OS_UNIX
  45 #include "gunixfdmessage.h"
  46 #include "gunixconnection.h"
  47 #include "gunixcredentialsmessage.h"
  48 #endif
  49
  50 #ifdef G_OS_WIN32
  51 #include <windows.h>
  52 #endif
  53
  54 #include "glibintl.h"
  55 #include "gioalias.h"
  56
  57 /* ---------------------------------------------------------------------------------------------------- */
  58
  59 gchar *
  60 _g_dbus_hexdump (const gchar *data, gsize len, guint indent)
  61 {
  62  guint n, m;
  63  GString *ret;
  64
  65  ret = g_string_new (NULL);
  66
  67  for (n = 0; n < len; n += 16)
  68    {
  69      g_string_append_printf (ret, "%*s%04x: ", indent, "", n);
  70
  71      for (m = n; m < n + 16; m++)
  72        {
  73          if (m > n && (m%4) == 0)
  74            g_string_append_c (ret, ' ');
  75          if (m < len)
  76            g_string_append_printf (ret, "%02x ", (guchar) data[m]);
  77          else
  78            g_string_append (ret, "   ");
  79        }
  80
  81      g_string_append (ret, "   ");
  82
  83      for (m = n; m < len && m < n + 16; m++)
  84        g_string_append_c (ret, g_ascii_isprint (data[m]) ? data[m] : '.');
  85
  86      g_string_append_c (ret, '\n');
  87    }
  88
  89  return g_string_free (ret, FALSE);
  90 }
  91
  92 /* ---------------------------------------------------------------------------------------------------- */
  93
  94 /* Unfortunately ancillary messages are discarded when reading from a
  95  * socket using the GSocketInputStream abstraction. So we provide a
  96  * very GInputStream-ish API that uses GSocket in this case (very
  97  * similar to GSocketInputStream).
  98  */
  99
 100 typedef struct
 101 {
 102   GSocket *socket;
 103   GCancellable *cancellable;
 104
 105   void *buffer;
 106   gsize count;
 107
 108   GSocketControlMessage ***messages;
 109   gint *num_messages;
 110
 111   GSimpleAsyncResult *simple;
 112
 113   gboolean from_mainloop;
 114 } ReadWithControlData;
 115
 116 static void
 117 read_with_control_data_free (ReadWithControlData *data)
 118 {
 119   g_object_unref (data->socket);
 120   if (data->cancellable != NULL)
 121     g_object_unref (data->cancellable);
 122   g_free (data);
 123 }
 124
 125 static gboolean
 126 _g_socket_read_with_control_messages_ready (GSocket      *socket,
 127                                             GIOCondition  condition,
 128                                             gpointer      user_data)
 129 {
 130   ReadWithControlData *data = user_data;
 131   GError *error;
 132   gssize result;
 133   GInputVector vector;
 134
 135   error = NULL;
 136   vector.buffer = data->buffer;
 137   vector.size = data->count;
 138   result = g_socket_receive_message (data->socket,
 139                                      NULL, /* address */
 140                                      &vector,
 141                                      1,
 142                                      data->messages,
 143                                      data->num_messages,
 144                                      NULL,
 145                                      data->cancellable,
 146                                      &error);
 147   if (result >= 0)
 148     {
 149       g_simple_async_result_set_op_res_gssize (data->simple, result);
 150     }
 151   else
 152     {
 153       g_assert (error != NULL);
 154       g_simple_async_result_set_from_error (data->simple, error);
 155       g_error_free (error);
 156     }
 157
 158   if (data->from_mainloop)
 159     g_simple_async_result_complete (data->simple);
 160   else
 161     g_simple_async_result_complete_in_idle (data->simple);
 162
 163   return FALSE;
 164 }
 165
 166 static void
 167 _g_socket_read_with_control_messages (GSocket                 *socket,
 168                                       void                    *buffer,
 169                                       gsize                    count,
 170                                       GSocketControlMessage ***messages,
 171                                       gint                    *num_messages,
 172                                       gint                     io_priority,
 173                                       GCancellable            *cancellable,
 174                                       GAsyncReadyCallback      callback,
 175                                       gpointer                 user_data)
 176 {
 177   ReadWithControlData *data;
 178
 179   data = g_new0 (ReadWithControlData, 1);
 180   data->socket = g_object_ref (socket);
 181   data->cancellable = cancellable != NULL ? g_object_ref (cancellable) : NULL;
 182   data->buffer = buffer;
 183   data->count = count;
 184   data->messages = messages;
 185   data->num_messages = num_messages;
 186
 187   data->simple = g_simple_async_result_new (G_OBJECT (socket),
 188                                             callback,
 189                                             user_data,
 190                                             _g_socket_read_with_control_messages);
 191
 192   if (!g_socket_condition_check (socket, G_IO_IN))
 193     {
 194       GSource *source;
 195       data->from_mainloop = TRUE;
 196       source = g_socket_create_source (data->socket,
 197                                        G_IO_IN | G_IO_HUP | G_IO_ERR,
 198                                        cancellable);
 199       g_source_set_callback (source,
 200                              (GSourceFunc) _g_socket_read_with_control_messages_ready,
 201                              data,
 202                              (GDestroyNotify) read_with_control_data_free);
 203       g_source_attach (source, g_main_context_get_thread_default ());
 204       g_source_unref (source);
 205     }
 206   else
 207     {
 208       _g_socket_read_with_control_messages_ready (data->socket, G_IO_IN, data);
 209       read_with_control_data_free (data);
 210     }
 211 }
 212
 213 static gssize
 214 _g_socket_read_with_control_messages_finish (GSocket       *socket,
 215                                              GAsyncResult  *result,
 216                                              GError       **error)
 217 {
 218   GSimpleAsyncResult *simple = G_SIMPLE_ASYNC_RESULT (result);
 219
 220   g_return_val_if_fail (G_IS_SOCKET (socket), -1);
 221   g_warn_if_fail (g_simple_async_result_get_source_tag (simple) == _g_socket_read_with_control_messages);
 222
 223   if (g_simple_async_result_propagate_error (simple, error))
 224       return -1;
 225   else
 226     return g_simple_async_result_get_op_res_gssize (simple);
 227 }
 228
 229 /* ---------------------------------------------------------------------------------------------------- */
 230
 231 G_LOCK_DEFINE_STATIC (shared_thread_lock);
 232
 233 typedef struct
 234 {
 235   gint num_users;
 236   GThread *thread;
 237   GMainContext *context;
 238   GMainLoop *loop;
 239 } SharedThreadData;
 240
 241 static SharedThreadData *shared_thread_data = NULL;
 242
 243 static gpointer
 244 shared_thread_func (gpointer data)
 245 {
 246   g_main_context_push_thread_default (shared_thread_data->context);
 247   g_main_loop_run (shared_thread_data->loop);
 248   g_main_context_pop_thread_default (shared_thread_data->context);
 249   return NULL;
 250 }
 251
 252 typedef void (*GDBusSharedThreadFunc) (gpointer user_data);
 253
 254 typedef struct
 255 {
 256   GDBusSharedThreadFunc func;
 257   gpointer              user_data;
 258   gboolean              done;
 259 } CallerData;
 260
 261 static gboolean
 262 invoke_caller (gpointer user_data)
 263 {
 264   CallerData *data = user_data;
 265   data->func (data->user_data);
 266   data->done = TRUE;
 267   return FALSE;
 268 }
 269
 270 static void
 271 _g_dbus_shared_thread_ref (GDBusSharedThreadFunc func,
 272                            gpointer              user_data)
 273 {
 274   GError *error;
 275   GSource *idle_source;
 276   CallerData *data;
 277
 278   G_LOCK (shared_thread_lock);
 279
 280   if (shared_thread_data != NULL)
 281     {
 282       shared_thread_data->num_users += 1;
 283       goto have_thread;
 284     }
 285
 286   shared_thread_data = g_new0 (SharedThreadData, 1);
 287   shared_thread_data->num_users = 1;
 288
 289   error = NULL;
 290   shared_thread_data->context = g_main_context_new ();
 291   shared_thread_data->loop = g_main_loop_new (shared_thread_data->context, FALSE);
 292   shared_thread_data->thread = g_thread_create (shared_thread_func,
 293                                                 NULL,
 294                                                 TRUE,
 295                                                 &error);
 296   g_assert_no_error (error);
 297
 298  have_thread:
 299
 300   data = g_new0 (CallerData, 1);
 301   data->func = func;
 302   data->user_data = user_data;
 303   data->done = FALSE;
 304
 305   idle_source = g_idle_source_new ();
 306   g_source_set_priority (idle_source, G_PRIORITY_DEFAULT);
 307   g_source_set_callback (idle_source,
 308                          invoke_caller,
 309                          data,
 310                          NULL);
 311   g_source_attach (idle_source, shared_thread_data->context);
 312   g_source_unref (idle_source);
 313
 314   /* wait for the user code to run.. hmm.. probably use a condition variable instead */
 315   while (!data->done)
 316     g_thread_yield ();
 317
 318   g_free (data);
 319
 320   G_UNLOCK (shared_thread_lock);
 321 }
 322
 323 static void
 324 _g_dbus_shared_thread_unref (void)
 325 {
 326   /* TODO: actually destroy the shared thread here */
 327 #if 0
 328   G_LOCK (shared_thread_lock);
 329   g_assert (shared_thread_data != NULL);
 330   shared_thread_data->num_users -= 1;
 331   if (shared_thread_data->num_users == 0)
 332     {
 333       g_main_loop_quit (shared_thread_data->loop);
 334       //g_thread_join (shared_thread_data->thread);
 335       g_main_loop_unref (shared_thread_data->loop);
 336       g_main_context_unref (shared_thread_data->context);
 337       g_free (shared_thread_data);
 338       shared_thread_data = NULL;
 339       G_UNLOCK (shared_thread_lock);
 340     }
 341   else
 342     {
 343       G_UNLOCK (shared_thread_lock);
 344     }
 345 #endif
 346 }
 347
 348 /* ---------------------------------------------------------------------------------------------------- */
 349
 350 struct GDBusWorker
 351 {
 352   volatile gint                       ref_count;
 353
 354   gboolean                            stopped;
 355
 356   /* TODO: frozen (e.g. G_DBUS_CONNECTION_FLAGS_DELAY_MESSAGE_PROCESSING) currently
 357    * only affects messages received from the other peer (since GDBusServer is the
 358    * only user) - we might want it to affect messages sent to the other peer too?
 359    */
 360   gboolean                            frozen;
 361   GQueue                             *received_messages_while_frozen;
 362
 363   GIOStream                          *stream;
 364   GDBusCapabilityFlags                capabilities;
 365   GCancellable                       *cancellable;
 366   GDBusWorkerMessageReceivedCallback  message_received_callback;
 367   GDBusWorkerMessageAboutToBeSentCallback message_about_to_be_sent_callback;
 368   GDBusWorkerDisconnectedCallback     disconnected_callback;
 369   gpointer                            user_data;
 370
 371   GThread                            *thread;
 372
 373   /* if not NULL, stream is GSocketConnection */
 374   GSocket *socket;
 375
 376   /* used for reading */
 377   GMutex                             *read_lock;
 378   gchar                              *read_buffer;
 379   gsize                               read_buffer_allocated_size;
 380   gsize                               read_buffer_cur_size;
 381   gsize                               read_buffer_bytes_wanted;
 382   GUnixFDList                        *read_fd_list;
 383   GSocketControlMessage             **read_ancillary_messages;
 384   gint                                read_num_ancillary_messages;
 385
 386   /* used for writing */
 387   GMutex                             *write_lock;
 388   GQueue                             *write_queue;
 389   gboolean                            write_is_pending;
 390 };
 391
 392 struct _MessageToWriteData ;
 393 typedef struct _MessageToWriteData MessageToWriteData;
 394
 395 static void message_to_write_data_free (MessageToWriteData *data);
 396
 397 static GDBusWorker *
 398 _g_dbus_worker_ref (GDBusWorker *worker)
 399 {
 400   g_atomic_int_inc (&worker->ref_count);
 401   return worker;
 402 }
 403
 404 static void
 405 _g_dbus_worker_unref (GDBusWorker *worker)
 406 {
 407   if (g_atomic_int_dec_and_test (&worker->ref_count))
 408     {
 409       _g_dbus_shared_thread_unref ();
 410
 411       g_object_unref (worker->stream);
 412
 413       g_mutex_free (worker->read_lock);
 414       g_object_unref (worker->cancellable);
 415       if (worker->read_fd_list != NULL)
 416         g_object_unref (worker->read_fd_list);
 417
 418       g_queue_foreach (worker->received_messages_while_frozen, (GFunc) g_object_unref, NULL);
 419       g_queue_free (worker->received_messages_while_frozen);
 420
 421       g_mutex_free (worker->write_lock);
 422       g_queue_foreach (worker->write_queue, (GFunc) message_to_write_data_free, NULL);
 423       g_queue_free (worker->write_queue);
 424
 425       g_free (worker);
 426     }
 427 }
 428
 429 static void
 430 _g_dbus_worker_emit_disconnected (GDBusWorker  *worker,
 431                                   gboolean      remote_peer_vanished,
 432                                   GError       *error)
 433 {
 434   if (!worker->stopped)
 435     worker->disconnected_callback (worker, remote_peer_vanished, error, worker->user_data);
 436 }
 437
 438 static void
 439 _g_dbus_worker_emit_message_received (GDBusWorker  *worker,
 440                                       GDBusMessage *message)
 441 {
 442   if (!worker->stopped)
 443     worker->message_received_callback (worker, message, worker->user_data);
 444 }
 445
 446 static gboolean
 447 _g_dbus_worker_emit_message_about_to_be_sent (GDBusWorker  *worker,
 448                                               GDBusMessage *message)
 449 {
 450   gboolean ret;
 451   ret = FALSE;
 452   if (!worker->stopped)
 453     ret = worker->message_about_to_be_sent_callback (worker, message, worker->user_data);
 454   return ret;
 455 }
 456
 457 /* can only be called from private thread with read-lock held - takes ownership of @message */
 458 static void
 459 _g_dbus_worker_queue_or_deliver_received_message (GDBusWorker  *worker,
 460                                                   GDBusMessage *message)
 461 {
 462   if (worker->frozen || g_queue_get_length (worker->received_messages_while_frozen) > 0)
 463     {
 464       /* queue up */
 465       g_queue_push_tail (worker->received_messages_while_frozen, message);
 466     }
 467   else
 468     {
 469       /* not frozen, nor anything in queue */
 470       _g_dbus_worker_emit_message_received (worker, message);
 471       g_object_unref (message);
 472     }
 473 }
 474
 475 /* called in private thread shared by all GDBusConnection instances (without read-lock held) */
 476 static gboolean
 477 unfreeze_in_idle_cb (gpointer user_data)
 478 {
 479   GDBusWorker *worker = user_data;
 480   GDBusMessage *message;
 481
 482   g_mutex_lock (worker->read_lock);
 483   if (worker->frozen)
 484     {
 485       while ((message = g_queue_pop_head (worker->received_messages_while_frozen)) != NULL)
 486         {
 487           _g_dbus_worker_emit_message_received (worker, message);
 488           g_object_unref (message);
 489         }
 490       worker->frozen = FALSE;
 491     }
 492   else
 493     {
 494       g_assert (g_queue_get_length (worker->received_messages_while_frozen) == 0);
 495     }
 496   g_mutex_unlock (worker->read_lock);
 497   return FALSE;
 498 }
 499
 500 /* can be called from any thread */
 501 void
 502 _g_dbus_worker_unfreeze (GDBusWorker *worker)
 503 {
 504   GSource *idle_source;
 505   idle_source = g_idle_source_new ();
 506   g_source_set_priority (idle_source, G_PRIORITY_DEFAULT);
 507   g_source_set_callback (idle_source,
 508                          unfreeze_in_idle_cb,
 509                          _g_dbus_worker_ref (worker),
 510                          (GDestroyNotify) _g_dbus_worker_unref);
 511   g_source_attach (idle_source, shared_thread_data->context);
 512   g_source_unref (idle_source);
 513 }
 514
 515 /* ---------------------------------------------------------------------------------------------------- */
 516
 517 static void _g_dbus_worker_do_read_unlocked (GDBusWorker *worker);
 518
 519 /* called in private thread shared by all GDBusConnection instances (without read-lock held) */
 520 static void
 521 _g_dbus_worker_do_read_cb (GInputStream  *input_stream,
 522                            GAsyncResult  *res,
 523                            gpointer       user_data)
 524 {
 525   GDBusWorker *worker = user_data;
 526   GError *error;
 527   gssize bytes_read;
 528
 529   g_mutex_lock (worker->read_lock);
 530
 531   /* If already stopped, don't even process the reply */
 532   if (worker->stopped)
 533     goto out;
 534
 535   error = NULL;
 536   if (worker->socket == NULL)
 537     bytes_read = g_input_stream_read_finish (g_io_stream_get_input_stream (worker->stream),
 538                                              res,
 539                                              &error);
 540   else
 541     bytes_read = _g_socket_read_with_control_messages_finish (worker->socket,
 542                                                               res,
 543                                                               &error);
 544   if (worker->read_num_ancillary_messages > 0)
 545     {
 546       gint n;
 547       for (n = 0; n < worker->read_num_ancillary_messages; n++)
 548         {
 549           GSocketControlMessage *control_message = G_SOCKET_CONTROL_MESSAGE (worker->read_ancillary_messages[n]);
 550
 551           if (FALSE)
 552             {
 553             }
 554 #ifdef G_OS_UNIX
 555           else if (G_IS_UNIX_FD_MESSAGE (control_message))
 556             {
 557               GUnixFDMessage *fd_message;
 558               gint *fds;
 559               gint num_fds;
 560
 561               fd_message = G_UNIX_FD_MESSAGE (control_message);
 562               fds = g_unix_fd_message_steal_fds (fd_message, &num_fds);
 563               if (worker->read_fd_list == NULL)
 564                 {
 565                   worker->read_fd_list = g_unix_fd_list_new_from_array (fds, num_fds);
 566                 }
 567               else
 568                 {
 569                   gint n;
 570                   for (n = 0; n < num_fds; n++)
 571                     {
 572                       /* TODO: really want a append_steal() */
 573                       g_unix_fd_list_append (worker->read_fd_list, fds[n], NULL);
 574                       close (fds[n]);
 575                     }
 576                 }
 577               g_free (fds);
 578             }
 579           else if (G_IS_UNIX_CREDENTIALS_MESSAGE (control_message))
 580             {
 581               /* do nothing */
 582             }
 583 #endif
 584           else
 585             {
 586               if (error == NULL)
 587                 {
 588                   g_set_error (&error,
 589                                G_IO_ERROR,
 590                                G_IO_ERROR_FAILED,
 591                                "Unexpected ancillary message of type %s received from peer",
 592                                g_type_name (G_TYPE_FROM_INSTANCE (control_message)));
 593                   _g_dbus_worker_emit_disconnected (worker, TRUE, error);
 594                   g_error_free (error);
 595                   g_object_unref (control_message);
 596                   n++;
 597                   while (n < worker->read_num_ancillary_messages)
 598                     g_object_unref (worker->read_ancillary_messages[n++]);
 599                   g_free (worker->read_ancillary_messages);
 600                   goto out;
 601                 }
 602             }
 603           g_object_unref (control_message);
 604         }
 605       g_free (worker->read_ancillary_messages);
 606     }
 607
 608   if (bytes_read == -1)
 609     {
 610       _g_dbus_worker_emit_disconnected (worker, TRUE, error);
 611       g_error_free (error);
 612       goto out;
 613     }
 614
 615 #if 0
 616   g_debug ("read %d bytes (is_closed=%d blocking=%d condition=0x%02x) stream %p, %p",
 617            (gint) bytes_read,
 618            g_socket_is_closed (g_socket_connection_get_socket (G_SOCKET_CONNECTION (worker->stream))),
 619            g_socket_get_blocking (g_socket_connection_get_socket (G_SOCKET_CONNECTION (worker->stream))),
 620            g_socket_condition_check (g_socket_connection_get_socket (G_SOCKET_CONNECTION (worker->stream)),
 621                                      G_IO_IN | G_IO_OUT | G_IO_HUP),
 622            worker->stream,
 623            worker);
 624 #endif
 625
 626   /* TODO: hmm, hmm... */
 627   if (bytes_read == 0)
 628     {
 629       g_set_error (&error,
 630                    G_IO_ERROR,
 631                    G_IO_ERROR_FAILED,
 632                    "Underlying GIOStream returned 0 bytes on an async read");
 633       _g_dbus_worker_emit_disconnected (worker, TRUE, error);
 634       g_error_free (error);
 635       goto out;
 636     }
 637
 638   worker->read_buffer_cur_size += bytes_read;
 639   if (worker->read_buffer_bytes_wanted == worker->read_buffer_cur_size)
 640     {
 641       /* OK, got what we asked for! */
 642       if (worker->read_buffer_bytes_wanted == 16)
 643         {
 644           gssize message_len;
 645           /* OK, got the header - determine how many more bytes are needed */
 646           error = NULL;
 647           message_len = g_dbus_message_bytes_needed ((guchar *) worker->read_buffer,
 648                                                      16,
 649                                                      &error);
 650           if (message_len == -1)
 651             {
 652               g_warning ("_g_dbus_worker_do_read_cb: error determing bytes needed: %s", error->message);
 653               _g_dbus_worker_emit_disconnected (worker, FALSE, error);
 654               g_error_free (error);
 655               goto out;
 656             }
 657
 658           worker->read_buffer_bytes_wanted = message_len;
 659           _g_dbus_worker_do_read_unlocked (worker);
 660         }
 661       else
 662         {
 663           GDBusMessage *message;
 664           error = NULL;
 665
 666           /* TODO: use connection->priv->auth to decode the message */
 667
 668           message = g_dbus_message_new_from_blob ((guchar *) worker->read_buffer,
 669                                                   worker->read_buffer_cur_size,
 670                                                   worker->capabilities,
 671                                                   &error);
 672           if (message == NULL)
 673             {
 674               gchar *s;
 675               s = _g_dbus_hexdump (worker->read_buffer, worker->read_buffer_cur_size, 2);
 676               g_warning ("Error decoding D-Bus message of %" G_GSIZE_FORMAT " bytes\n"
 677                          "The error is: %s\n"
 678                          "The payload is as follows:\n"
 679                          "%s\n",
 680                          worker->read_buffer_cur_size,
 681                          error->message,
 682                          s);
 683               g_free (s);
 684               _g_dbus_worker_emit_disconnected (worker, FALSE, error);
 685               g_error_free (error);
 686               goto out;
 687             }
 688
 689 #ifdef G_OS_UNIX
 690           if (worker->read_fd_list != NULL)
 691             {
 692               g_dbus_message_set_unix_fd_list (message, worker->read_fd_list);
 693               worker->read_fd_list = NULL;
 694             }
 695 #endif
 696
 697           if (G_UNLIKELY (_g_dbus_debug_message ()))
 698             {
 699               gchar *s;
 700               g_print ("========================================================================\n"
 701                        "GDBus-debug:Message:\n"
 702                        "  <<<< RECEIVED D-Bus message (%" G_GSIZE_FORMAT " bytes)\n",
 703                        worker->read_buffer_cur_size);
 704               s = g_dbus_message_print (message, 2);
 705               g_print ("%s", s);
 706               g_free (s);
 707               s = _g_dbus_hexdump (worker->read_buffer, worker->read_buffer_cur_size, 2);
 708               g_print ("%s\n", s);
 709               g_free (s);
 710             }
 711
 712           /* yay, got a message, go deliver it */
 713           _g_dbus_worker_queue_or_deliver_received_message (worker, message);
 714
 715           /* start reading another message! */
 716           worker->read_buffer_bytes_wanted = 0;
 717           worker->read_buffer_cur_size = 0;
 718           _g_dbus_worker_do_read_unlocked (worker);
 719         }
 720     }
 721   else
 722     {
 723       /* didn't get all the bytes we requested - so repeat the request... */
 724       _g_dbus_worker_do_read_unlocked (worker);
 725     }
 726
 727  out:
 728   g_mutex_unlock (worker->read_lock);
 729
 730   /* gives up the reference acquired when calling g_input_stream_read_async() */
 731   _g_dbus_worker_unref (worker);
 732 }
 733
 734 /* called in private thread shared by all GDBusConnection instances (with read-lock held) */
 735 static void
 736 _g_dbus_worker_do_read_unlocked (GDBusWorker *worker)
 737 {
 738   /* if bytes_wanted is zero, it means start reading a message */
 739   if (worker->read_buffer_bytes_wanted == 0)
 740     {
 741       worker->read_buffer_cur_size = 0;
 742       worker->read_buffer_bytes_wanted = 16;
 743     }
 744
 745   /* ensure we have a (big enough) buffer */
 746   if (worker->read_buffer == NULL || worker->read_buffer_bytes_wanted > worker->read_buffer_allocated_size)
 747     {
 748       /* TODO: 4096 is randomly chosen; might want a better chosen default minimum */
 749       worker->read_buffer_allocated_size = MAX (worker->read_buffer_bytes_wanted, 4096);
 750       worker->read_buffer = g_realloc (worker->read_buffer, worker->read_buffer_allocated_size);
 751     }
 752
 753   if (worker->socket == NULL)
 754     g_input_stream_read_async (g_io_stream_get_input_stream (worker->stream),
 755                                worker->read_buffer + worker->read_buffer_cur_size,
 756                                worker->read_buffer_bytes_wanted - worker->read_buffer_cur_size,
 757                                G_PRIORITY_DEFAULT,
 758                                worker->cancellable,
 759                                (GAsyncReadyCallback) _g_dbus_worker_do_read_cb,
 760                                _g_dbus_worker_ref (worker));
 761   else
 762     {
 763       worker->read_ancillary_messages = NULL;
 764       worker->read_num_ancillary_messages = 0;
 765       _g_socket_read_with_control_messages (worker->socket,
 766                                             worker->read_buffer + worker->read_buffer_cur_size,
 767                                             worker->read_buffer_bytes_wanted - worker->read_buffer_cur_size,
 768                                             &worker->read_ancillary_messages,
 769                                             &worker->read_num_ancillary_messages,
 770                                             G_PRIORITY_DEFAULT,
 771                                             worker->cancellable,
 772                                             (GAsyncReadyCallback) _g_dbus_worker_do_read_cb,
 773                                             _g_dbus_worker_ref (worker));
 774     }
 775 }
 776
 777 /* called in private thread shared by all GDBusConnection instances (without read-lock held) */
 778 static void
 779 _g_dbus_worker_do_read (GDBusWorker *worker)
 780 {
 781   g_mutex_lock (worker->read_lock);
 782   _g_dbus_worker_do_read_unlocked (worker);
 783   g_mutex_unlock (worker->read_lock);
 784 }
 785
 786 /* ---------------------------------------------------------------------------------------------------- */
 787
 788 struct _MessageToWriteData
 789 {
 790   GDBusMessage *message;
 791   gchar        *blob;
 792   gsize         blob_size;
 793 };
 794
 795 static void
 796 message_to_write_data_free (MessageToWriteData *data)
 797 {
 798   g_object_unref (data->message);
 799   g_free (data->blob);
 800   g_free (data);
 801 }
 802
 803 /* ---------------------------------------------------------------------------------------------------- */
 804
 805 /* called in private thread shared by all GDBusConnection instances (without write-lock held) */
 806 static gboolean
 807 write_message (GDBusWorker         *worker,
 808                MessageToWriteData  *data,
 809                GError             **error)
 810 {
 811   gboolean ret;
 812
 813   g_return_val_if_fail (data->blob_size > 16, FALSE);
 814
 815   ret = FALSE;
 816
 817   /* First, the initial 16 bytes - special case UNIX sockets here
 818    * since it may involve writing an ancillary message with file
 819    * descriptors
 820    */
 821 #ifdef G_OS_UNIX
 822   {
 823     GOutputVector vector;
 824     GSocketControlMessage *message;
 825     GUnixFDList *fd_list;
 826     gssize bytes_written;
 827
 828     fd_list = g_dbus_message_get_unix_fd_list (data->message);
 829
 830     message = NULL;
 831     if (fd_list != NULL)
 832       {
 833         if (!G_IS_UNIX_CONNECTION (worker->stream))
 834           {
 835             g_set_error (error,
 836                          G_IO_ERROR,
 837                          G_IO_ERROR_INVALID_ARGUMENT,
 838                          "Tried sending a file descriptor on unsupported stream of type %s",
 839                          g_type_name (G_TYPE_FROM_INSTANCE (worker->stream)));
 840             goto out;
 841           }
 842         else if (!(worker->capabilities & G_DBUS_CAPABILITY_FLAGS_UNIX_FD_PASSING))
 843           {
 844             g_set_error_literal (error,
 845                                  G_IO_ERROR,
 846                                  G_IO_ERROR_INVALID_ARGUMENT,
 847                                  "Tried sending a file descriptor but remote peer does not support this capability");
 848             goto out;
 849           }
 850         message = g_unix_fd_message_new_with_fd_list (fd_list);
 851       }
 852
 853     vector.buffer = data->blob;
 854     vector.size = 16;
 855
 856     bytes_written = g_socket_send_message (worker->socket,
 857                                            NULL, /* address */
 858                                            &vector,
 859                                            1,
 860                                            message != NULL ? &message : NULL,
 861                                            message != NULL ? 1 : 0,
 862                                            G_SOCKET_MSG_NONE,
 863                                            worker->cancellable,
 864                                            error);
 865     if (bytes_written == -1)
 866       {
 867         g_prefix_error (error, _("Error writing first 16 bytes of message to socket: "));
 868         if (message != NULL)
 869           g_object_unref (message);
 870         goto out;
 871       }
 872     if (message != NULL)
 873       g_object_unref (message);
 874
 875     if (bytes_written < 16)
 876       {
 877         /* TODO: I think this needs to be handled ... are we guaranteed that the ancillary
 878          * messages are sent?
 879          */
 880         g_assert_not_reached ();
 881       }
 882   }
 883 #else
 884   /* write the first 16 bytes (guaranteed to return an error if everything can't be written) */
 885   if (!g_output_stream_write_all (g_io_stream_get_output_stream (worker->stream),
 886                                   (const gchar *) data->blob,
 887                                   16,
 888                                   NULL, /* bytes_written */
 889                                   worker->cancellable, /* cancellable */
 890                                   error))
 891     goto out;
 892 #endif
 893
 894   /* Then write the rest of the message (guaranteed to return an error if everything can't be written) */
 895   if (!g_output_stream_write_all (g_io_stream_get_output_stream (worker->stream),
 896                                   (const gchar *) data->blob + 16,
 897                                   data->blob_size - 16,
 898                                   NULL, /* bytes_written */
 899                                   worker->cancellable, /* cancellable */
 900                                   error))
 901     goto out;
 902
 903   ret = TRUE;
 904
 905   if (G_UNLIKELY (_g_dbus_debug_message ()))
 906     {
 907       gchar *s;
 908       g_print ("========================================================================\n"
 909                "GDBus-debug:Message:\n"
 910                "  >>>> SENT D-Bus message (%" G_GSIZE_FORMAT " bytes)\n",
 911                data->blob_size);
 912       s = g_dbus_message_print (data->message, 2);
 913       g_print ("%s", s);
 914       g_free (s);
 915       s = _g_dbus_hexdump (data->blob, data->blob_size, 2);
 916       g_print ("%s\n", s);
 917       g_free (s);
 918     }
 919
 920  out:
 921   return ret;
 922 }
 923
 924 /* ---------------------------------------------------------------------------------------------------- */
 925
 926 /* called in private thread shared by all GDBusConnection instances (without write-lock held) */
 927 static gboolean
 928 write_message_in_idle_cb (gpointer user_data)
 929 {
 930   GDBusWorker *worker = user_data;
 931   gboolean more_writes_are_pending;
 932   MessageToWriteData *data;
 933   gboolean message_was_dropped;
 934   GError *error;
 935
 936   g_mutex_lock (worker->write_lock);
 937   data = g_queue_pop_head (worker->write_queue);
 938   g_assert (data != NULL);
 939   more_writes_are_pending = (g_queue_get_length (worker->write_queue) > 0);
 940   worker->write_is_pending = more_writes_are_pending;
 941   g_mutex_unlock (worker->write_lock);
 942
 943   /* Note that write_lock is only used for protecting the @write_queue
 944    * and @write_is_pending fields of the GDBusWorker struct ... which we
 945    * need to modify from arbitrary threads in _g_dbus_worker_send_message().
 946    *
 947    * Therefore, it's fine to drop it here when calling back into user
 948    * code and then writing the message out onto the GIOStream since this
 949    * function only runs on the worker thread.
 950    */
 951   message_was_dropped = _g_dbus_worker_emit_message_about_to_be_sent (worker, data->message);
 952   if (G_LIKELY (!message_was_dropped))
 953     {
 954       error = NULL;
 955       if (!write_message (worker,
 956                           data,
 957                           &error))
 958         {
 959           /* TODO: handle */
 960           _g_dbus_worker_emit_disconnected (worker, TRUE, error);
 961           g_error_free (error);
 962         }
 963     }
 964   message_to_write_data_free (data);
 965
 966   return more_writes_are_pending;
 967 }
 968
 969 /* ---------------------------------------------------------------------------------------------------- */
 970
 971 /* can be called from any thread - steals blob */
 972 void
 973 _g_dbus_worker_send_message (GDBusWorker    *worker,
 974                              GDBusMessage   *message,
 975                              gchar          *blob,
 976                              gsize           blob_len)
 977 {
 978   MessageToWriteData *data;
 979
 980   g_return_if_fail (G_IS_DBUS_MESSAGE (message));
 981   g_return_if_fail (blob != NULL);
 982   g_return_if_fail (blob_len > 16);
 983
 984   data = g_new0 (MessageToWriteData, 1);
 985   data->message = g_object_ref (message);
 986   data->blob = blob; /* steal! */
 987   data->blob_size = blob_len;
 988
 989   g_mutex_lock (worker->write_lock);
 990   g_queue_push_tail (worker->write_queue, data);
 991   if (!worker->write_is_pending)
 992     {
 993       GSource *idle_source;
 994
 995       worker->write_is_pending = TRUE;
 996
 997       idle_source = g_idle_source_new ();
 998       g_source_set_priority (idle_source, G_PRIORITY_DEFAULT);
 999       g_source_set_callback (idle_source,
1000                              write_message_in_idle_cb,
1001                              _g_dbus_worker_ref (worker),
1002                              (GDestroyNotify) _g_dbus_worker_unref);
1003       g_source_attach (idle_source, shared_thread_data->context);
1004       g_source_unref (idle_source);
1005     }
1006   g_mutex_unlock (worker->write_lock);
1007 }
1008
1009 /* ---------------------------------------------------------------------------------------------------- */
1010
1011 static void
1012 _g_dbus_worker_thread_begin_func (gpointer user_data)
1013 {
1014   GDBusWorker *worker = user_data;
1015
1016   worker->thread = g_thread_self ();
1017
1018   /* begin reading */
1019   _g_dbus_worker_do_read (worker);
1020 }
1021
1022 GDBusWorker *
1023 _g_dbus_worker_new (GIOStream                              *stream,
1024                     GDBusCapabilityFlags                    capabilities,
1025                     gboolean                                initially_frozen,
1026                     GDBusWorkerMessageReceivedCallback      message_received_callback,
1027                     GDBusWorkerMessageAboutToBeSentCallback message_about_to_be_sent_callback,
1028                     GDBusWorkerDisconnectedCallback         disconnected_callback,
1029                     gpointer                                user_data)
1030 {
1031   GDBusWorker *worker;
1032
1033   g_return_val_if_fail (G_IS_IO_STREAM (stream), NULL);
1034   g_return_val_if_fail (message_received_callback != NULL, NULL);
1035   g_return_val_if_fail (message_about_to_be_sent_callback != NULL, NULL);
1036   g_return_val_if_fail (disconnected_callback != NULL, NULL);
1037
1038   worker = g_new0 (GDBusWorker, 1);
1039   worker->ref_count = 1;
1040
1041   worker->read_lock = g_mutex_new ();
1042   worker->message_received_callback = message_received_callback;
1043   worker->message_about_to_be_sent_callback = message_about_to_be_sent_callback;
1044   worker->disconnected_callback = disconnected_callback;
1045   worker->user_data = user_data;
1046   worker->stream = g_object_ref (stream);
1047   worker->capabilities = capabilities;
1048   worker->cancellable = g_cancellable_new ();
1049
1050   worker->frozen = initially_frozen;
1051   worker->received_messages_while_frozen = g_queue_new ();
1052
1053   worker->write_lock = g_mutex_new ();
1054   worker->write_queue = g_queue_new ();
1055
1056   if (G_IS_SOCKET_CONNECTION (worker->stream))
1057     worker->socket = g_socket_connection_get_socket (G_SOCKET_CONNECTION (worker->stream));
1058
1059   _g_dbus_shared_thread_ref (_g_dbus_worker_thread_begin_func, worker);
1060
1061   return worker;
1062 }
1063
1064 /* This can be called from any thread - frees worker - guarantees no callbacks
1065  * will ever be issued again
1066  */
1067 void
1068 _g_dbus_worker_stop (GDBusWorker *worker)
1069 {
1070   /* If we're called in the worker thread it means we are called from
1071    * a worker callback. This is fine, we just can't lock in that case since
1072    * we're already holding the lock...
1073    */
1074   if (g_thread_self () != worker->thread)
1075     g_mutex_lock (worker->read_lock);
1076   worker->stopped = TRUE;
1077   if (g_thread_self () != worker->thread)
1078     g_mutex_unlock (worker->read_lock);
1079
1080   g_cancellable_cancel (worker->cancellable);
1081   _g_dbus_worker_unref (worker);
1082 }
1083
1084 #define G_DBUS_DEBUG_AUTHENTICATION (1<<0)
1085 #define G_DBUS_DEBUG_MESSAGE        (1<<1)
1086 #define G_DBUS_DEBUG_ALL            0xffffffff
1087 static gint _gdbus_debug_flags = 0;
1088
1089 gboolean
1090 _g_dbus_debug_authentication (void)
1091 {
1092   _g_dbus_initialize ();
1093   return (_gdbus_debug_flags & G_DBUS_DEBUG_AUTHENTICATION) != 0;
1094 }
1095
1096 gboolean
1097 _g_dbus_debug_message (void)
1098 {
1099   _g_dbus_initialize ();
1100   return (_gdbus_debug_flags & G_DBUS_DEBUG_MESSAGE) != 0;
1101 }
1102
1103 /*
1104  * _g_dbus_initialize:
1105  *
1106  * Does various one-time init things such as
1107  *
1108  *  - registering the G_DBUS_ERROR error domain
1109  *  - parses the G_DBUS_DEBUG environment variable
1110  */
1111 void
1112 _g_dbus_initialize (void)
1113 {
1114   static volatile gsize initialized = 0;
1115
1116   if (g_once_init_enter (&initialized))
1117     {
1118       volatile GQuark g_dbus_error_domain;
1119       const gchar *debug;
1120
1121       g_dbus_error_domain = G_DBUS_ERROR;
1122
1123       debug = g_getenv ("G_DBUS_DEBUG");
1124       if (debug != NULL)
1125         {
1126           gchar **tokens;
1127           guint n;
1128           tokens = g_strsplit (debug, ",", 0);
1129           for (n = 0; tokens[n] != NULL; n++)
1130             {
1131               if (g_strcmp0 (tokens[n], "authentication") == 0)
1132                 _gdbus_debug_flags |= G_DBUS_DEBUG_AUTHENTICATION;
1133               else if (g_strcmp0 (tokens[n], "message") == 0)
1134                 _gdbus_debug_flags |= G_DBUS_DEBUG_MESSAGE;
1135               else if (g_strcmp0 (tokens[n], "all") == 0)
1136                 _gdbus_debug_flags |= G_DBUS_DEBUG_ALL;
1137             }
1138           g_strfreev (tokens);
1139         }
1140
1141       g_once_init_leave (&initialized, 1);
1142     }
1143 }
1144
1145 /* ---------------------------------------------------------------------------------------------------- */
1146
1147 GVariantType *
1148 _g_dbus_compute_complete_signature (GDBusArgInfo **args)
1149 {
1150   const GVariantType *arg_types[256];
1151   guint n;
1152
1153   if (args)
1154     for (n = 0; args[n] != NULL; n++)
1155       {
1156         /* DBus places a hard limit of 255 on signature length.
1157          * therefore number of args must be less than 256.
1158          */
1159         g_assert (n < 256);
1160
1161         arg_types[n] = G_VARIANT_TYPE (args[n]->signature);
1162
1163         if G_UNLIKELY (arg_types[n] == NULL)
1164           return NULL;
1165       }
1166   else
1167     n = 0;
1168
1169   return g_variant_type_new_tuple (arg_types, n);
1170 }
1171
1172 /* ---------------------------------------------------------------------------------------------------- */
1173
1174 #ifdef G_OS_WIN32
1175
1176 extern BOOL WINAPI ConvertSidToStringSidA (PSID Sid, LPSTR *StringSid);
1177
1178 gchar *
1179 _g_dbus_win32_get_user_sid (void)
1180 {
1181   HANDLE h;
1182   TOKEN_USER *user;
1183   DWORD token_information_len;
1184   PSID psid;
1185   gchar *sid;
1186   gchar *ret;
1187
1188   ret = NULL;
1189   user = NULL;
1190   h = INVALID_HANDLE_VALUE;
1191
1192   if (!OpenProcessToken (GetCurrentProcess (), TOKEN_QUERY, &h))
1193     {
1194       g_warning ("OpenProcessToken failed with error code %d", (gint) GetLastError ());
1195       goto out;
1196     }
1197
1198   /* Get length of buffer */
1199   token_information_len = 0;
1200   if (!GetTokenInformation (h, TokenUser, NULL, 0, &token_information_len))
1201     {
1202       if (GetLastError () != ERROR_INSUFFICIENT_BUFFER)
1203         {
1204           g_warning ("GetTokenInformation() failed with error code %d", (gint) GetLastError ());
1205           goto out;
1206         }
1207     }
1208   user = g_malloc (token_information_len);
1209   if (!GetTokenInformation (h, TokenUser, user, token_information_len, &token_information_len))
1210     {
1211       g_warning ("GetTokenInformation() failed with error code %d", (gint) GetLastError ());
1212       goto out;
1213     }
1214
1215   psid = user->User.Sid;
1216   if (!IsValidSid (psid))
1217     {
1218       g_warning ("Invalid SID");
1219       goto out;
1220     }
1221
1222   if (!ConvertSidToStringSidA (psid, &sid))
1223     {
1224       g_warning ("Invalid SID");
1225       goto out;
1226     }
1227
1228   ret = g_strdup (sid);
1229   LocalFree (sid);
1230
1231 out:
1232   g_free (user);
1233   if (h != INVALID_HANDLE_VALUE)
1234     CloseHandle (h);
1235   return ret;
1236 }
1237 #endif
1238
1239 /* ---------------------------------------------------------------------------------------------------- */
1240
1241 #define __G_DBUS_PRIVATE_C__
1242 #include "gioaliasdef.c"