dbus-connection.c

/* -*- mode: C; c-file-style: "gnu" -*- */
/* dbus-connection.c DBusConnection object
 *
 * Copyright (C) 2002, 2003, 2004, 2005  Red Hat Inc.
 *
 * Licensed under the Academic Free License version 2.1
 * 
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#include <config.h>
#include "dbus-shared.h"
#include "dbus-connection.h"
#include "dbus-list.h"
#include "dbus-timeout.h"
#include "dbus-transport.h"
#include "dbus-watch.h"
#include "dbus-connection-internal.h"
#include "dbus-list.h"
#include "dbus-hash.h"
#include "dbus-message-internal.h"
#include "dbus-threads.h"
#include "dbus-protocol.h"
#include "dbus-dataslot.h"
#include "dbus-string.h"
#include "dbus-pending-call.h"
#include "dbus-object-tree.h"
#include "dbus-threads-internal.h"

#ifdef DBUS_DISABLE_CHECKS
#define TOOK_LOCK_CHECK(connection)
#define RELEASING_LOCK_CHECK(connection)
#define HAVE_LOCK_CHECK(connection)
#else
#define TOOK_LOCK_CHECK(connection) do {                \
    _dbus_assert (!(connection)->have_connection_lock); \
    (connection)->have_connection_lock = TRUE;          \
  } while (0)
#define RELEASING_LOCK_CHECK(connection) do {            \
    _dbus_assert ((connection)->have_connection_lock);   \
    (connection)->have_connection_lock = FALSE;          \
  } while (0)
#define HAVE_LOCK_CHECK(connection)        _dbus_assert ((connection)->have_connection_lock)
/* A "DO_NOT_HAVE_LOCK_CHECK" is impossible since we need the lock to check the flag */
#endif

#define TRACE_LOCKS 1

#define CONNECTION_LOCK(connection)   do {                                      \
    if (TRACE_LOCKS) { _dbus_verbose ("  LOCK: %s\n", _DBUS_FUNCTION_NAME); }   \
    _dbus_mutex_lock ((connection)->mutex);                                      \
    TOOK_LOCK_CHECK (connection);                                               \
  } while (0)

#define CONNECTION_UNLOCK(connection) do {                                              \
    if (TRACE_LOCKS) { _dbus_verbose ("  UNLOCK: %s\n", _DBUS_FUNCTION_NAME);  }        \
    RELEASING_LOCK_CHECK (connection);                                                  \
    _dbus_mutex_unlock ((connection)->mutex);                                            \
  } while (0)

#define DISPATCH_STATUS_NAME(s)                                            \
                     ((s) == DBUS_DISPATCH_COMPLETE ? "complete" :         \
                      (s) == DBUS_DISPATCH_DATA_REMAINS ? "data remains" : \
                      (s) == DBUS_DISPATCH_NEED_MEMORY ? "need memory" :   \
                      "???")

typedef struct DBusMessageFilter DBusMessageFilter;

struct DBusMessageFilter
{
  DBusAtomic refcount; 
  DBusHandleMessageFunction function; 
  void *user_data; 
  DBusFreeFunction free_user_data_function; 
};


struct DBusPreallocatedSend
{
  DBusConnection *connection; 
  DBusList *queue_link;       
  DBusList *counter_link;     
};

static dbus_bool_t _dbus_modify_sigpipe = TRUE;

struct DBusConnection
{
  DBusAtomic refcount; 
  DBusMutex *mutex; 
  DBusMutex *dispatch_mutex;     
  DBusCondVar *dispatch_cond;    
  DBusMutex *io_path_mutex;      
  DBusCondVar *io_path_cond;     
  DBusList *outgoing_messages; 
  DBusList *incoming_messages; 
  DBusMessage *message_borrowed; 
  int n_outgoing;              
  int n_incoming;              
  DBusCounter *outgoing_counter; 
  DBusTransport *transport;    
  DBusWatchList *watches;      
  DBusTimeoutList *timeouts;   
  DBusList *filter_list;        
  DBusDataSlotList slot_list;   
  DBusHashTable *pending_replies;  
  dbus_uint32_t client_serial;       
  DBusList *disconnect_message_link; 
  DBusWakeupMainFunction wakeup_main_function; 
  void *wakeup_main_data; 
  DBusFreeFunction free_wakeup_main_data; 
  DBusDispatchStatusFunction dispatch_status_function; 
  void *dispatch_status_data; 
  DBusFreeFunction free_dispatch_status_data; 
  DBusDispatchStatus last_dispatch_status; 
  DBusList *link_cache; 
  DBusObjectTree *objects; 
  char *server_guid; 
  unsigned int shareable : 1; 
  unsigned int dispatch_acquired : 1; 
  unsigned int io_path_acquired : 1;  
  unsigned int exit_on_disconnect : 1; 
#ifndef DBUS_DISABLE_CHECKS
  unsigned int have_connection_lock : 1; 
#endif
  
#ifndef DBUS_DISABLE_CHECKS
  int generation; 
#endif 
};

static DBusDispatchStatus _dbus_connection_get_dispatch_status_unlocked      (DBusConnection     *connection);
static void               _dbus_connection_update_dispatch_status_and_unlock (DBusConnection     *connection,
                                                                              DBusDispatchStatus  new_status);
static void               _dbus_connection_last_unref                        (DBusConnection     *connection);
static void               _dbus_connection_acquire_dispatch                  (DBusConnection     *connection);
static void               _dbus_connection_release_dispatch                  (DBusConnection     *connection);

static DBusMessageFilter *
_dbus_message_filter_ref (DBusMessageFilter *filter)
{
  _dbus_assert (filter->refcount.value > 0);
  _dbus_atomic_inc (&filter->refcount);

  return filter;
}

static void
_dbus_message_filter_unref (DBusMessageFilter *filter)
{
  _dbus_assert (filter->refcount.value > 0);

  if (_dbus_atomic_dec (&filter->refcount) == 1)
    {
      if (filter->free_user_data_function)
        (* filter->free_user_data_function) (filter->user_data);
      
      dbus_free (filter);
    }
}

void
_dbus_connection_lock (DBusConnection *connection)
{
  CONNECTION_LOCK (connection);
}

void
_dbus_connection_unlock (DBusConnection *connection)
{
  CONNECTION_UNLOCK (connection);
}

static void
_dbus_connection_wakeup_mainloop (DBusConnection *connection)
{
  if (connection->wakeup_main_function)
    (*connection->wakeup_main_function) (connection->wakeup_main_data);
}

#ifdef DBUS_BUILD_TESTS
/* For now this function isn't used */
dbus_bool_t
_dbus_connection_queue_received_message (DBusConnection *connection,
                                         DBusMessage    *message)
{
  DBusList *link;

  link = _dbus_list_alloc_link (message);
  if (link == NULL)
    return FALSE;

  dbus_message_ref (message);
  _dbus_connection_queue_received_message_link (connection, link);

  return TRUE;
}
#endif

void
_dbus_connection_queue_received_message_link (DBusConnection  *connection,
                                              DBusList        *link)
{
  DBusPendingCall *pending;
  dbus_int32_t reply_serial;
  DBusMessage *message;
  
  _dbus_assert (_dbus_transport_get_is_authenticated (connection->transport));
  
  _dbus_list_append_link (&connection->incoming_messages,
                          link);
  message = link->data;

  /* If this is a reply we're waiting on, remove timeout for it */
  reply_serial = dbus_message_get_reply_serial (message);
  if (reply_serial != -1)
    {
      pending = _dbus_hash_table_lookup_int (connection->pending_replies,
                                             reply_serial);
      if (pending != NULL)
        {
          if (pending->timeout_added)
            _dbus_connection_remove_timeout_unlocked (connection,
                                                      pending->timeout);

          pending->timeout_added = FALSE;
        }
    }
  
  connection->n_incoming += 1;

  _dbus_connection_wakeup_mainloop (connection);
  
  _dbus_verbose ("Message %p (%d %s %s %s '%s' reply to %u) added to incoming queue %p, %d incoming\n",
                 message,
                 dbus_message_get_type (message),
                 dbus_message_get_path (message) ?
                 dbus_message_get_path (message) :
                 "no path",
                 dbus_message_get_interface (message) ?
                 dbus_message_get_interface (message) :
                 "no interface",
                 dbus_message_get_member (message) ?
                 dbus_message_get_member (message) :
                 "no member",
                 dbus_message_get_signature (message),
                 dbus_message_get_reply_serial (message),
                 connection,
                 connection->n_incoming);
}

static void
_dbus_connection_queue_synthesized_message_link (DBusConnection *connection,
                                                 DBusList *link)
{
  HAVE_LOCK_CHECK (connection);
  
  _dbus_list_append_link (&connection->incoming_messages, link);

  connection->n_incoming += 1;

  _dbus_connection_wakeup_mainloop (connection);
  
  _dbus_verbose ("Synthesized message %p added to incoming queue %p, %d incoming\n",
                 link->data, connection, connection->n_incoming);
}


dbus_bool_t
_dbus_connection_has_messages_to_send_unlocked (DBusConnection *connection)
{
  HAVE_LOCK_CHECK (connection);
  return connection->outgoing_messages != NULL;
}

dbus_bool_t
dbus_connection_has_messages_to_send (DBusConnection *connection)
{
  dbus_bool_t v;
  
  _dbus_return_val_if_fail (connection != NULL, FALSE);

  CONNECTION_LOCK (connection);
  v = _dbus_connection_has_messages_to_send_unlocked (connection);
  CONNECTION_UNLOCK (connection);

  return v;
}

DBusMessage*
_dbus_connection_get_message_to_send (DBusConnection *connection)
{
  HAVE_LOCK_CHECK (connection);
  
  return _dbus_list_get_last (&connection->outgoing_messages);
}

void
_dbus_connection_message_sent (DBusConnection *connection,
                               DBusMessage    *message)
{
  DBusList *link;

  HAVE_LOCK_CHECK (connection);
  
  /* This can be called before we even complete authentication, since
   * it's called on disconnect to clean up the outgoing queue.
   * It's also called as we successfully send each message.
   */
  
  link = _dbus_list_get_last_link (&connection->outgoing_messages);
  _dbus_assert (link != NULL);
  _dbus_assert (link->data == message);

  /* Save this link in the link cache */
  _dbus_list_unlink (&connection->outgoing_messages,
                     link);
  _dbus_list_prepend_link (&connection->link_cache, link);
  
  connection->n_outgoing -= 1;

  _dbus_verbose ("Message %p (%d %s %s %s '%s') removed from outgoing queue %p, %d left to send\n",
                 message,
                 dbus_message_get_type (message),
                 dbus_message_get_path (message) ?
                 dbus_message_get_path (message) :
                 "no path",
                 dbus_message_get_interface (message) ?
                 dbus_message_get_interface (message) :
                 "no interface",
                 dbus_message_get_member (message) ?
                 dbus_message_get_member (message) :
                 "no member",
                 dbus_message_get_signature (message),
                 connection, connection->n_outgoing);

  /* Save this link in the link cache also */
  _dbus_message_remove_size_counter (message, connection->outgoing_counter,
                                     &link);
  _dbus_list_prepend_link (&connection->link_cache, link);
  
  dbus_message_unref (message);
}

typedef dbus_bool_t (* DBusWatchAddFunction)     (DBusWatchList *list,
                                                  DBusWatch     *watch);
typedef void        (* DBusWatchRemoveFunction)  (DBusWatchList *list,
                                                  DBusWatch     *watch);
typedef void        (* DBusWatchToggleFunction)  (DBusWatchList *list,
                                                  DBusWatch     *watch,
                                                  dbus_bool_t    enabled);

static dbus_bool_t
protected_change_watch (DBusConnection         *connection,
                        DBusWatch              *watch,
                        DBusWatchAddFunction    add_function,
                        DBusWatchRemoveFunction remove_function,
                        DBusWatchToggleFunction toggle_function,
                        dbus_bool_t             enabled)
{
  DBusWatchList *watches;
  dbus_bool_t retval;
  
  HAVE_LOCK_CHECK (connection);

  /* This isn't really safe or reasonable; a better pattern is the "do everything, then
   * drop lock and call out" one; but it has to be propagated up through all callers
   */
  
  watches = connection->watches;
  if (watches)
    {
      connection->watches = NULL;
      _dbus_connection_ref_unlocked (connection);
      CONNECTION_UNLOCK (connection);

      if (add_function)
        retval = (* add_function) (watches, watch);
      else if (remove_function)
        {
          retval = TRUE;
          (* remove_function) (watches, watch);
        }
      else
        {
          retval = TRUE;
          (* toggle_function) (watches, watch, enabled);
        }
      
      CONNECTION_LOCK (connection);
      connection->watches = watches;
      _dbus_connection_unref_unlocked (connection);

      return retval;
    }
  else
    return FALSE;
}
     

dbus_bool_t
_dbus_connection_add_watch_unlocked (DBusConnection *connection,
                                     DBusWatch      *watch)
{
  return protected_change_watch (connection, watch,
                                 _dbus_watch_list_add_watch,
                                 NULL, NULL, FALSE);
}

void
_dbus_connection_remove_watch_unlocked (DBusConnection *connection,
                                        DBusWatch      *watch)
{
  protected_change_watch (connection, watch,
                          NULL,
                          _dbus_watch_list_remove_watch,
                          NULL, FALSE);
}

void
_dbus_connection_toggle_watch_unlocked (DBusConnection *connection,
                                        DBusWatch      *watch,
                                        dbus_bool_t     enabled)
{
  _dbus_assert (watch != NULL);

  protected_change_watch (connection, watch,
                          NULL, NULL,
                          _dbus_watch_list_toggle_watch,
                          enabled);
}

typedef dbus_bool_t (* DBusTimeoutAddFunction)    (DBusTimeoutList *list,
                                                   DBusTimeout     *timeout);
typedef void        (* DBusTimeoutRemoveFunction) (DBusTimeoutList *list,
                                                   DBusTimeout     *timeout);
typedef void        (* DBusTimeoutToggleFunction) (DBusTimeoutList *list,
                                                   DBusTimeout     *timeout,
                                                   dbus_bool_t      enabled);

static dbus_bool_t
protected_change_timeout (DBusConnection           *connection,
                          DBusTimeout              *timeout,
                          DBusTimeoutAddFunction    add_function,
                          DBusTimeoutRemoveFunction remove_function,
                          DBusTimeoutToggleFunction toggle_function,
                          dbus_bool_t               enabled)
{
  DBusTimeoutList *timeouts;
  dbus_bool_t retval;
  
  HAVE_LOCK_CHECK (connection);

  /* This isn't really safe or reasonable; a better pattern is the "do everything, then
   * drop lock and call out" one; but it has to be propagated up through all callers
   */
  
  timeouts = connection->timeouts;
  if (timeouts)
    {
      connection->timeouts = NULL;
      _dbus_connection_ref_unlocked (connection);
      CONNECTION_UNLOCK (connection);

      if (add_function)
        retval = (* add_function) (timeouts, timeout);
      else if (remove_function)
        {
          retval = TRUE;
          (* remove_function) (timeouts, timeout);
        }
      else
        {
          retval = TRUE;
          (* toggle_function) (timeouts, timeout, enabled);
        }
      
      CONNECTION_LOCK (connection);
      connection->timeouts = timeouts;
      _dbus_connection_unref_unlocked (connection);

      return retval;
    }
  else
    return FALSE;
}

dbus_bool_t
_dbus_connection_add_timeout_unlocked (DBusConnection *connection,
                                       DBusTimeout    *timeout)
{
  return protected_change_timeout (connection, timeout,
                                   _dbus_timeout_list_add_timeout,
                                   NULL, NULL, FALSE);
}

void
_dbus_connection_remove_timeout_unlocked (DBusConnection *connection,
                                          DBusTimeout    *timeout)
{
  protected_change_timeout (connection, timeout,
                            NULL,
                            _dbus_timeout_list_remove_timeout,
                            NULL, FALSE);
}

void
_dbus_connection_toggle_timeout_unlocked (DBusConnection   *connection,
                                          DBusTimeout      *timeout,
                                          dbus_bool_t       enabled)
{
  protected_change_timeout (connection, timeout,
                            NULL, NULL,
                            _dbus_timeout_list_toggle_timeout,
                            enabled);
}

static dbus_bool_t
_dbus_connection_attach_pending_call_unlocked (DBusConnection  *connection,
                                               DBusPendingCall *pending)
{
  HAVE_LOCK_CHECK (connection);
  
  _dbus_assert (pending->reply_serial != 0);

  if (!_dbus_connection_add_timeout_unlocked (connection, pending->timeout))
    return FALSE;
  
  if (!_dbus_hash_table_insert_int (connection->pending_replies,
                                    pending->reply_serial,
                                    pending))
    {
      _dbus_connection_remove_timeout_unlocked (connection, pending->timeout);

      HAVE_LOCK_CHECK (connection);
      return FALSE;
    }
  
  pending->timeout_added = TRUE;
  pending->connection = connection;

  dbus_pending_call_ref (pending);

  HAVE_LOCK_CHECK (connection);
  
  return TRUE;
}

static void
free_pending_call_on_hash_removal (void *data)
{
  DBusPendingCall *pending;
  
  if (data == NULL)
    return;

  pending = data;

  if (pending->connection)
    {
      if (pending->timeout_added)
        {
          _dbus_connection_remove_timeout_unlocked (pending->connection,
                                                    pending->timeout);
          pending->timeout_added = FALSE;
        }

      pending->connection = NULL;
      
      dbus_pending_call_unref (pending);
    }
}

static void
_dbus_connection_detach_pending_call_unlocked (DBusConnection  *connection,
                                               DBusPendingCall *pending)
{
  /* Can't have a destroy notifier on the pending call if we're going to do this */

  dbus_pending_call_ref (pending);
  _dbus_hash_table_remove_int (connection->pending_replies,
                               pending->reply_serial);
  _dbus_assert (pending->connection == NULL);
  dbus_pending_call_unref (pending);
}

static void
_dbus_connection_detach_pending_call_and_unlock (DBusConnection  *connection,
                                                 DBusPendingCall *pending)
{
  /* The idea here is to avoid finalizing the pending call
   * with the lock held, since there's a destroy notifier
   * in pending call that goes out to application code.
   */
  dbus_pending_call_ref (pending);
  _dbus_hash_table_remove_int (connection->pending_replies,
                               pending->reply_serial);
  _dbus_assert (pending->connection == NULL);
  CONNECTION_UNLOCK (connection);
  dbus_pending_call_unref (pending);
}

void
_dbus_connection_remove_pending_call (DBusConnection  *connection,
                                      DBusPendingCall *pending)
{
  CONNECTION_LOCK (connection);
  _dbus_connection_detach_pending_call_and_unlock (connection, pending);
}

void
_dbus_pending_call_complete_and_unlock (DBusPendingCall *pending,
                                        DBusMessage     *message)
{
  if (message == NULL)
    {
      message = pending->timeout_link->data;
      _dbus_list_clear (&pending->timeout_link);
    }
  else
    dbus_message_ref (message);

  _dbus_verbose ("  handing message %p (%s) to pending call serial %u\n",
                 message,
                 dbus_message_get_type (message) == DBUS_MESSAGE_TYPE_METHOD_RETURN ?
                 "method return" :
                 dbus_message_get_type (message) == DBUS_MESSAGE_TYPE_ERROR ?
                 "error" : "other type",
                 pending->reply_serial);
  
  _dbus_assert (pending->reply == NULL);
  _dbus_assert (pending->reply_serial == dbus_message_get_reply_serial (message));
  pending->reply = message;
  
  dbus_pending_call_ref (pending); /* in case there's no app with a ref held */
  _dbus_connection_detach_pending_call_and_unlock (pending->connection, pending);
  
  /* Must be called unlocked since it invokes app callback */
  _dbus_pending_call_notify (pending);
  dbus_pending_call_unref (pending);
}

static dbus_bool_t
_dbus_connection_acquire_io_path (DBusConnection *connection,
                                  int timeout_milliseconds)
{
  dbus_bool_t we_acquired;
  
  HAVE_LOCK_CHECK (connection);

  /* We don't want the connection to vanish */
  _dbus_connection_ref_unlocked (connection);

  /* We will only touch io_path_acquired which is protected by our mutex */
  CONNECTION_UNLOCK (connection);
  
  _dbus_verbose ("%s locking io_path_mutex\n", _DBUS_FUNCTION_NAME);
  _dbus_mutex_lock (connection->io_path_mutex);

  _dbus_verbose ("%s start connection->io_path_acquired = %d timeout = %d\n",
                 _DBUS_FUNCTION_NAME, connection->io_path_acquired, timeout_milliseconds);

  we_acquired = FALSE;
  
  if (connection->io_path_acquired)
    {
      if (timeout_milliseconds != -1)
        {
          _dbus_verbose ("%s waiting %d for IO path to be acquirable\n",
                         _DBUS_FUNCTION_NAME, timeout_milliseconds);
          _dbus_condvar_wait_timeout (connection->io_path_cond,
                                      connection->io_path_mutex,
                                      timeout_milliseconds);
        }
      else
        {
          while (connection->io_path_acquired)
            {
              _dbus_verbose ("%s waiting for IO path to be acquirable\n", _DBUS_FUNCTION_NAME);
              _dbus_condvar_wait (connection->io_path_cond, connection->io_path_mutex);
            }
        }
    }
  
  if (!connection->io_path_acquired)
    {
      we_acquired = TRUE;
      connection->io_path_acquired = TRUE;
    }
  
  _dbus_verbose ("%s end connection->io_path_acquired = %d we_acquired = %d\n",
                 _DBUS_FUNCTION_NAME, connection->io_path_acquired, we_acquired);

  _dbus_verbose ("%s unlocking io_path_mutex\n", _DBUS_FUNCTION_NAME);
  _dbus_mutex_unlock (connection->io_path_mutex);

  CONNECTION_LOCK (connection);
  
  HAVE_LOCK_CHECK (connection);

  _dbus_connection_unref_unlocked (connection);
  
  return we_acquired;
}

static void
_dbus_connection_release_io_path (DBusConnection *connection)
{
  HAVE_LOCK_CHECK (connection);
  
  _dbus_verbose ("%s locking io_path_mutex\n", _DBUS_FUNCTION_NAME);
  _dbus_mutex_lock (connection->io_path_mutex);
  
  _dbus_assert (connection->io_path_acquired);

  _dbus_verbose ("%s start connection->io_path_acquired = %d\n",
                 _DBUS_FUNCTION_NAME, connection->io_path_acquired);
  
  connection->io_path_acquired = FALSE;
  _dbus_condvar_wake_one (connection->io_path_cond);

  _dbus_verbose ("%s unlocking io_path_mutex\n", _DBUS_FUNCTION_NAME);
  _dbus_mutex_unlock (connection->io_path_mutex);
}

void
_dbus_connection_do_iteration_unlocked (DBusConnection *connection,
                                        unsigned int    flags,
                                        int             timeout_milliseconds)
{
  _dbus_verbose ("%s start\n", _DBUS_FUNCTION_NAME);
  
  HAVE_LOCK_CHECK (connection);
  
  if (connection->n_outgoing == 0)
    flags &= ~DBUS_ITERATION_DO_WRITING;

  if (_dbus_connection_acquire_io_path (connection,
                                        (flags & DBUS_ITERATION_BLOCK) ? timeout_milliseconds : 0))
    {
      HAVE_LOCK_CHECK (connection);
      
      _dbus_transport_do_iteration (connection->transport,
                                    flags, timeout_milliseconds);
      _dbus_connection_release_io_path (connection);
    }

  HAVE_LOCK_CHECK (connection);

  _dbus_verbose ("%s end\n", _DBUS_FUNCTION_NAME);
}

DBusConnection*
_dbus_connection_new_for_transport (DBusTransport *transport)
{
  DBusConnection *connection;
  DBusWatchList *watch_list;
  DBusTimeoutList *timeout_list;
  DBusHashTable *pending_replies;
  DBusMutex *mutex;
  DBusMutex *io_path_mutex;
  DBusMutex *dispatch_mutex;
  DBusCondVar *dispatch_cond;
  DBusCondVar *io_path_cond;
  DBusList *disconnect_link;
  DBusMessage *disconnect_message;
  DBusCounter *outgoing_counter;
  DBusObjectTree *objects;
  
  watch_list = NULL;
  connection = NULL;
  pending_replies = NULL;
  timeout_list = NULL;
  mutex = NULL;
  io_path_mutex = NULL;
  dispatch_mutex = NULL;
  dispatch_cond = NULL;
  io_path_cond = NULL;
  disconnect_link = NULL;
  disconnect_message = NULL;
  outgoing_counter = NULL;
  objects = NULL;
  
  watch_list = _dbus_watch_list_new ();
  if (watch_list == NULL)
    goto error;

  timeout_list = _dbus_timeout_list_new ();
  if (timeout_list == NULL)
    goto error;  

  pending_replies =
    _dbus_hash_table_new (DBUS_HASH_INT,
                          NULL,
                          (DBusFreeFunction)free_pending_call_on_hash_removal);
  if (pending_replies == NULL)
    goto error;
  
  connection = dbus_new0 (DBusConnection, 1);
  if (connection == NULL)
    goto error;

  mutex = _dbus_mutex_new ();
  if (mutex == NULL)
    goto error;

  io_path_mutex = _dbus_mutex_new ();
  if (io_path_mutex == NULL)
    goto error;

  dispatch_mutex = _dbus_mutex_new ();
  if (dispatch_mutex == NULL)
    goto error;
  
  dispatch_cond = _dbus_condvar_new ();
  if (dispatch_cond == NULL)
    goto error;
  
  io_path_cond = _dbus_condvar_new ();
  if (io_path_cond == NULL)
    goto error;

  disconnect_message = dbus_message_new_signal (DBUS_PATH_LOCAL,
                                                DBUS_INTERFACE_LOCAL,
                                                "Disconnected");
  
  if (disconnect_message == NULL)
    goto error;

  disconnect_link = _dbus_list_alloc_link (disconnect_message);
  if (disconnect_link == NULL)
    goto error;

  outgoing_counter = _dbus_counter_new ();
  if (outgoing_counter == NULL)
    goto error;

  objects = _dbus_object_tree_new (connection);
  if (objects == NULL)
    goto error;
  
  if (_dbus_modify_sigpipe)
    _dbus_disable_sigpipe ();
  
  connection->refcount.value = 1;
  connection->mutex = mutex;
  connection->dispatch_cond = dispatch_cond;
  connection->dispatch_mutex = dispatch_mutex;
  connection->io_path_cond = io_path_cond;
  connection->io_path_mutex = io_path_mutex;
  connection->transport = transport;
  connection->watches = watch_list;
  connection->timeouts = timeout_list;
  connection->pending_replies = pending_replies;
  connection->outgoing_counter = outgoing_counter;
  connection->filter_list = NULL;
  connection->last_dispatch_status = DBUS_DISPATCH_COMPLETE; /* so we're notified first time there's data */
  connection->objects = objects;
  connection->exit_on_disconnect = FALSE;
  connection->shareable = FALSE;
#ifndef DBUS_DISABLE_CHECKS
  connection->generation = _dbus_current_generation;
#endif
  
  _dbus_data_slot_list_init (&connection->slot_list);

  connection->client_serial = 1;

  connection->disconnect_message_link = disconnect_link;

  CONNECTION_LOCK (connection);
  
  if (!_dbus_transport_set_connection (transport, connection))
    goto error;

  _dbus_transport_ref (transport);

  CONNECTION_UNLOCK (connection);
  
  return connection;
  
 error:
  if (disconnect_message != NULL)
    dbus_message_unref (disconnect_message);
  
  if (disconnect_link != NULL)
    _dbus_list_free_link (disconnect_link);
  
  if (io_path_cond != NULL)
    _dbus_condvar_free (io_path_cond);
  
  if (dispatch_cond != NULL)
    _dbus_condvar_free (dispatch_cond);
  
  if (mutex != NULL)
    _dbus_mutex_free (mutex);

  if (io_path_mutex != NULL)
    _dbus_mutex_free (io_path_mutex);

  if (dispatch_mutex != NULL)
    _dbus_mutex_free (dispatch_mutex);
  
  if (connection != NULL)
    dbus_free (connection);

  if (pending_replies)
    _dbus_hash_table_unref (pending_replies);
  
  if (watch_list)
    _dbus_watch_list_free (watch_list);

  if (timeout_list)
    _dbus_timeout_list_free (timeout_list);

  if (outgoing_counter)
    _dbus_counter_unref (outgoing_counter);

  if (objects)
    _dbus_object_tree_unref (objects);
  
  return NULL;
}

DBusConnection *
_dbus_connection_ref_unlocked (DBusConnection *connection)
{  
  _dbus_assert (connection != NULL);
  _dbus_assert (connection->generation == _dbus_current_generation);

  HAVE_LOCK_CHECK (connection);
  
#ifdef DBUS_HAVE_ATOMIC_INT
  _dbus_atomic_inc (&connection->refcount);
#else
  _dbus_assert (connection->refcount.value > 0);
  connection->refcount.value += 1;
#endif

  return connection;
}

void
_dbus_connection_unref_unlocked (DBusConnection *connection)
{
  dbus_bool_t last_unref;

  HAVE_LOCK_CHECK (connection);
  
  _dbus_assert (connection != NULL);

  /* The connection lock is better than the global
   * lock in the atomic increment fallback
   */
  
#ifdef DBUS_HAVE_ATOMIC_INT
  last_unref = (_dbus_atomic_dec (&connection->refcount) == 1);
#else
  _dbus_assert (connection->refcount.value > 0);

  connection->refcount.value -= 1;
  last_unref = (connection->refcount.value == 0);  
#if 0
  printf ("unref_unlocked() connection %p count = %d\n", connection, connection->refcount.value);
#endif
#endif
  
  if (last_unref)
    _dbus_connection_last_unref (connection);
}

static dbus_uint32_t
_dbus_connection_get_next_client_serial (DBusConnection *connection)
{
  int serial;

  serial = connection->client_serial++;

  if (connection->client_serial < 0)
    connection->client_serial = 1;
  
  return serial;
}

dbus_bool_t
_dbus_connection_handle_watch (DBusWatch                   *watch,
                               unsigned int                 condition,
                               void                        *data)
{
  DBusConnection *connection;
  dbus_bool_t retval;
  DBusDispatchStatus status;

  connection = data;

  _dbus_verbose ("%s start\n", _DBUS_FUNCTION_NAME);
  
  CONNECTION_LOCK (connection);
  _dbus_connection_acquire_io_path (connection, -1);
  HAVE_LOCK_CHECK (connection);
  retval = _dbus_transport_handle_watch (connection->transport,
                                         watch, condition);

  _dbus_connection_release_io_path (connection);

  HAVE_LOCK_CHECK (connection);

  _dbus_verbose ("%s middle\n", _DBUS_FUNCTION_NAME);
  
  status = _dbus_connection_get_dispatch_status_unlocked (connection);

  /* this calls out to user code */
  _dbus_connection_update_dispatch_status_and_unlock (connection, status);

  _dbus_verbose ("%s end\n", _DBUS_FUNCTION_NAME);
  
  return retval;
}

_DBUS_DEFINE_GLOBAL_LOCK (shared_connections);
static DBusHashTable *shared_connections = NULL;

static void
shared_connections_shutdown (void *data)
{
  _DBUS_LOCK (shared_connections);

  _dbus_assert (_dbus_hash_table_get_n_entries (shared_connections) == 0);
  _dbus_hash_table_unref (shared_connections);
  shared_connections = NULL;
  
  _DBUS_UNLOCK (shared_connections);
}

static dbus_bool_t
connection_lookup_shared (DBusAddressEntry  *entry,
                          DBusConnection   **result)
{
  _dbus_verbose ("checking for existing connection\n");
  
  *result = NULL;
  
  _DBUS_LOCK (shared_connections);

  if (shared_connections == NULL)
    {
      _dbus_verbose ("creating shared_connections hash table\n");
      
      shared_connections = _dbus_hash_table_new (DBUS_HASH_STRING,
                                                 dbus_free,
                                                 NULL);
      if (shared_connections == NULL)
        {
          _DBUS_UNLOCK (shared_connections);
          return FALSE;
        }

      if (!_dbus_register_shutdown_func (shared_connections_shutdown, NULL))
        {
          _dbus_hash_table_unref (shared_connections);
          shared_connections = NULL;
          _DBUS_UNLOCK (shared_connections);
          return FALSE;
        }

      _dbus_verbose ("  successfully created shared_connections\n");
      
      _DBUS_UNLOCK (shared_connections);
      return TRUE; /* no point looking up in the hash we just made */
    }
  else
    {
      const char *guid;

      guid = dbus_address_entry_get_value (entry, "guid");
      
      if (guid != NULL)
        {
          *result = _dbus_hash_table_lookup_string (shared_connections,
                                                    guid);

          if (*result)
            {
              /* The DBusConnection can't have been disconnected
               * between the lookup and this code, because the
               * disconnection will take the shared_connections lock to
               * remove the connection. It can't have been finalized
               * since you have to disconnect prior to finalize.
               *
               * Thus it's safe to ref the connection.
               */
              dbus_connection_ref (*result);

              _dbus_verbose ("looked up existing connection to server guid %s\n",
                             guid);
            }
        }
      
      _DBUS_UNLOCK (shared_connections);
      return TRUE;
    }
}

static dbus_bool_t
connection_record_shared_unlocked (DBusConnection *connection,
                                   const char     *guid)
{
  char *guid_key;
  char *guid_in_connection;

  /* A separate copy of the key is required in the hash table, because
   * we don't have a lock on the connection when we are doing a hash
   * lookup.
   */
  
  _dbus_assert (connection->server_guid == NULL);
  _dbus_assert (connection->shareable);
  
  guid_key = _dbus_strdup (guid);
  if (guid_key == NULL)
    return FALSE;

  guid_in_connection = _dbus_strdup (guid);
  if (guid_in_connection == NULL)
    {
      dbus_free (guid_key);
      return FALSE;
    }
  
  _DBUS_LOCK (shared_connections);
  _dbus_assert (shared_connections != NULL);
  
  if (!_dbus_hash_table_insert_string (shared_connections,
                                       guid_key, connection))
    {
      dbus_free (guid_key);
      dbus_free (guid_in_connection);
      _DBUS_UNLOCK (shared_connections);
      return FALSE;
    }

  connection->server_guid = guid_in_connection;

  _dbus_verbose ("stored connection to %s to be shared\n",
                 connection->server_guid);
  
  _DBUS_UNLOCK (shared_connections);

  _dbus_assert (connection->server_guid != NULL);
  
  return TRUE;
}

static void
connection_forget_shared_unlocked (DBusConnection *connection)
{
  HAVE_LOCK_CHECK (connection);
  
  if (connection->server_guid == NULL)
    return;

  _dbus_verbose ("dropping connection to %s out of the shared table\n",
                 connection->server_guid);
  
  _DBUS_LOCK (shared_connections);

  if (!_dbus_hash_table_remove_string (shared_connections,
                                       connection->server_guid))
    _dbus_assert_not_reached ("connection was not in the shared table");
  
  dbus_free (connection->server_guid);
  connection->server_guid = NULL;

  _DBUS_UNLOCK (shared_connections);
}

static DBusConnection*
connection_try_from_address_entry (DBusAddressEntry *entry,
                                   DBusError        *error)
{
  DBusTransport *transport;
  DBusConnection *connection;

  transport = _dbus_transport_open (entry, error);

  if (transport == NULL)
    {
      _DBUS_ASSERT_ERROR_IS_SET (error);
      return NULL;
    }

  connection = _dbus_connection_new_for_transport (transport);

  _dbus_transport_unref (transport);
  
  if (connection == NULL)
    {
      _DBUS_SET_OOM (error);
      return NULL;
    }

#ifndef DBUS_DISABLE_CHECKS
  _dbus_assert (!connection->have_connection_lock);
#endif
  return connection;
}

/*
 * If the shared parameter is true, then any existing connection will
 * be used (and if a new connection is created, it will be available
 * for use by others). If the shared parameter is false, a new
 * connection will always be created, and the new connection will
 * never be returned to other callers.
 *
 * @param address the address
 * @param shared whether the connection is shared or private
 * @param error error return
 * @returns the connection or #NULL on error
 */
static DBusConnection*
_dbus_connection_open_internal (const char     *address,
                                dbus_bool_t     shared,
                                DBusError      *error)
{
  DBusConnection *connection;
  DBusAddressEntry **entries;
  DBusError tmp_error;
  DBusError first_error;
  int len, i;

  _DBUS_ASSERT_ERROR_IS_CLEAR (error);

  _dbus_verbose ("opening %s connection to: %s\n",
                 shared ? "shared" : "private", address);
  
  if (!dbus_parse_address (address, &entries, &len, error))
    return NULL;

  _DBUS_ASSERT_ERROR_IS_CLEAR (error);
  
  connection = NULL;

  dbus_error_init (&tmp_error);
  dbus_error_init (&first_error);
  for (i = 0; i < len; i++)
    {
      if (shared)
        {
          if (!connection_lookup_shared (entries[i], &connection))
            _DBUS_SET_OOM (&tmp_error);
        }

      if (connection == NULL)
        {
          connection = connection_try_from_address_entry (entries[i],
                                                          &tmp_error);
          
          if (connection != NULL && shared)
            {
              const char *guid;

              connection->shareable = TRUE;
              
              guid = dbus_address_entry_get_value (entries[i], "guid");

              /* we don't have a connection lock but we know nobody
               * else has a handle to the connection
               */
              
              if (guid &&
                  !connection_record_shared_unlocked (connection, guid))
                {
                  _DBUS_SET_OOM (&tmp_error);
                  dbus_connection_close (connection);
                  dbus_connection_unref (connection);
                  connection = NULL;
                }

              /* but as of now the connection is possibly shared
               * since another thread could have pulled it from the table
               */
            }
        }
      
      if (connection)
        break;

      _DBUS_ASSERT_ERROR_IS_SET (&tmp_error);
      
      if (i == 0)
        dbus_move_error (&tmp_error, &first_error);
      else
        dbus_error_free (&tmp_error);
    }

  /* NOTE we don't have a lock on a possibly-shared connection object */
  
  _DBUS_ASSERT_ERROR_IS_CLEAR (error);
  _DBUS_ASSERT_ERROR_IS_CLEAR (&tmp_error);
  
  if (connection == NULL)
    {
      _DBUS_ASSERT_ERROR_IS_SET (&first_error);
      dbus_move_error (&first_error, error);
    }
  else
    {
      dbus_error_free (&first_error);
    }
  
  dbus_address_entries_free (entries);
  return connection;
}

DBusConnection*
dbus_connection_open (const char     *address,
                      DBusError      *error)
{
  DBusConnection *connection;

  _dbus_return_val_if_fail (address != NULL, NULL);
  _dbus_return_val_if_error_is_set (error, NULL);

  connection = _dbus_connection_open_internal (address,
                                               TRUE,
                                               error);

  return connection;
}

DBusConnection*
dbus_connection_open_private (const char     *address,
                              DBusError      *error)
{
  DBusConnection *connection;

  _dbus_return_val_if_fail (address != NULL, NULL);
  _dbus_return_val_if_error_is_set (error, NULL);

  connection = _dbus_connection_open_internal (address,
                                               FALSE,
                                               error);

  return connection;
}

DBusConnection *
dbus_connection_ref (DBusConnection *connection)
{
  _dbus_return_val_if_fail (connection != NULL, NULL);
  _dbus_return_val_if_fail (connection->generation == _dbus_current_generation, NULL);
  
  /* The connection lock is better than the global
   * lock in the atomic increment fallback
   */
  
#ifdef DBUS_HAVE_ATOMIC_INT
  _dbus_atomic_inc (&connection->refcount);
#else
  CONNECTION_LOCK (connection);
  _dbus_assert (connection->refcount.value > 0);

  connection->refcount.value += 1;
  CONNECTION_UNLOCK (connection);
#endif

  return connection;
}

static void
free_outgoing_message (void *element,
                       void *data)
{
  DBusMessage *message = element;
  DBusConnection *connection = data;

  _dbus_message_remove_size_counter (message,
                                     connection->outgoing_counter,
                                     NULL);
  dbus_message_unref (message);
}

/* This is run without the mutex held, but after the last reference
 * to the connection has been dropped we should have no thread-related
 * problems
 */
static void
_dbus_connection_last_unref (DBusConnection *connection)
{
  DBusList *link;

  _dbus_verbose ("Finalizing connection %p\n", connection);
  
  _dbus_assert (connection->refcount.value == 0);
  
  /* You have to disconnect the connection before unref:ing it. Otherwise
   * you won't get the disconnected message.
   */
  _dbus_assert (!_dbus_transport_get_is_connected (connection->transport));
  _dbus_assert (connection->server_guid == NULL);
  
  /* ---- We're going to call various application callbacks here, hope it doesn't break anything... */
  _dbus_object_tree_free_all_unlocked (connection->objects);
  
  dbus_connection_set_dispatch_status_function (connection, NULL, NULL, NULL);
  dbus_connection_set_wakeup_main_function (connection, NULL, NULL, NULL);
  dbus_connection_set_unix_user_function (connection, NULL, NULL, NULL);
  
  _dbus_watch_list_free (connection->watches);
  connection->watches = NULL;
  
  _dbus_timeout_list_free (connection->timeouts);
  connection->timeouts = NULL;

  _dbus_data_slot_list_free (&connection->slot_list);
  
  link = _dbus_list_get_first_link (&connection->filter_list);
  while (link != NULL)
    {
      DBusMessageFilter *filter = link->data;
      DBusList *next = _dbus_list_get_next_link (&connection->filter_list, link);

      filter->function = NULL;
      _dbus_message_filter_unref (filter); /* calls app callback */
      link->data = NULL;
      
      link = next;
    }
  _dbus_list_clear (&connection->filter_list);
  
  /* ---- Done with stuff that invokes application callbacks */

  _dbus_object_tree_unref (connection->objects);  

  _dbus_hash_table_unref (connection->pending_replies);
  connection->pending_replies = NULL;
  
  _dbus_list_clear (&connection->filter_list);
  
  _dbus_list_foreach (&connection->outgoing_messages,
                      free_outgoing_message,
                      connection);
  _dbus_list_clear (&connection->outgoing_messages);
  
  _dbus_list_foreach (&connection->incoming_messages,
                      (DBusForeachFunction) dbus_message_unref,
                      NULL);
  _dbus_list_clear (&connection->incoming_messages);

  _dbus_counter_unref (connection->outgoing_counter);

  _dbus_transport_unref (connection->transport);

  if (connection->disconnect_message_link)
    {
      DBusMessage *message = connection->disconnect_message_link->data;
      dbus_message_unref (message);
      _dbus_list_free_link (connection->disconnect_message_link);
    }

  _dbus_list_clear (&connection->link_cache);
  
  _dbus_condvar_free (connection->dispatch_cond);
  _dbus_condvar_free (connection->io_path_cond);

  _dbus_mutex_free (connection->io_path_mutex);
  _dbus_mutex_free (connection->dispatch_mutex);

  _dbus_mutex_free (connection->mutex);
  
  dbus_free (connection);
}

void
dbus_connection_unref (DBusConnection *connection)
{
  dbus_bool_t last_unref;

  _dbus_return_if_fail (connection != NULL);
  _dbus_return_if_fail (connection->generation == _dbus_current_generation);
  
  /* The connection lock is better than the global
   * lock in the atomic increment fallback
   */
  
#ifdef DBUS_HAVE_ATOMIC_INT
  last_unref = (_dbus_atomic_dec (&connection->refcount) == 1);
#else
  CONNECTION_LOCK (connection);
  
  _dbus_assert (connection->refcount.value > 0);

  connection->refcount.value -= 1;
  last_unref = (connection->refcount.value == 0);

#if 0
  printf ("unref() connection %p count = %d\n", connection, connection->refcount.value);
#endif
  
  CONNECTION_UNLOCK (connection);
#endif
  
  if (last_unref)
    _dbus_connection_last_unref (connection);
}

void
dbus_connection_close (DBusConnection *connection)
{
  DBusDispatchStatus status;
  
  _dbus_return_if_fail (connection != NULL);
  _dbus_return_if_fail (connection->generation == _dbus_current_generation);

  _dbus_verbose ("Disconnecting %p\n", connection);
  
  CONNECTION_LOCK (connection);
  
  _dbus_transport_disconnect (connection->transport);

  _dbus_verbose ("%s middle\n", _DBUS_FUNCTION_NAME);
  status = _dbus_connection_get_dispatch_status_unlocked (connection);

  /* this calls out to user code */
  _dbus_connection_update_dispatch_status_and_unlock (connection, status);
}

void
dbus_connection_disconnect (DBusConnection *connection)
{
  dbus_connection_close (connection);
}

static dbus_bool_t
_dbus_connection_get_is_connected_unlocked (DBusConnection *connection)
{
  HAVE_LOCK_CHECK (connection);
  return _dbus_transport_get_is_connected (connection->transport);
}

dbus_bool_t
dbus_connection_get_is_connected (DBusConnection *connection)
{
  dbus_bool_t res;

  _dbus_return_val_if_fail (connection != NULL, FALSE);
  
  CONNECTION_LOCK (connection);
  res = _dbus_connection_get_is_connected_unlocked (connection);
  CONNECTION_UNLOCK (connection);
  
  return res;
}

dbus_bool_t
dbus_connection_get_is_authenticated (DBusConnection *connection)
{
  dbus_bool_t res;

  _dbus_return_val_if_fail (connection != NULL, FALSE);
  
  CONNECTION_LOCK (connection);
  res = _dbus_transport_get_is_authenticated (connection->transport);
  CONNECTION_UNLOCK (connection);
  
  return res;
}

void
dbus_connection_set_exit_on_disconnect (DBusConnection *connection,
                                        dbus_bool_t     exit_on_disconnect)
{
  _dbus_return_if_fail (connection != NULL);

  CONNECTION_LOCK (connection);
  connection->exit_on_disconnect = exit_on_disconnect != FALSE;
  CONNECTION_UNLOCK (connection);
}

static DBusPreallocatedSend*
_dbus_connection_preallocate_send_unlocked (DBusConnection *connection)
{
  DBusPreallocatedSend *preallocated;

  HAVE_LOCK_CHECK (connection);
  
  _dbus_assert (connection != NULL);
  
  preallocated = dbus_new (DBusPreallocatedSend, 1);
  if (preallocated == NULL)
    return NULL;

  if (connection->link_cache != NULL)
    {
      preallocated->queue_link =
        _dbus_list_pop_first_link (&connection->link_cache);
      preallocated->queue_link->data = NULL;
    }
  else
    {
      preallocated->queue_link = _dbus_list_alloc_link (NULL);
      if (preallocated->queue_link == NULL)
        goto failed_0;
    }
  
  if (connection->link_cache != NULL)
    {
      preallocated->counter_link =
        _dbus_list_pop_first_link (&connection->link_cache);
      preallocated->counter_link->data = connection->outgoing_counter;
    }
  else
    {
      preallocated->counter_link = _dbus_list_alloc_link (connection->outgoing_counter);
      if (preallocated->counter_link == NULL)
        goto failed_1;
    }

  _dbus_counter_ref (preallocated->counter_link->data);

  preallocated->connection = connection;
  
  return preallocated;
  
 failed_1:
  _dbus_list_free_link (preallocated->queue_link);
 failed_0:
  dbus_free (preallocated);
  
  return NULL;
}

DBusPreallocatedSend*
dbus_connection_preallocate_send (DBusConnection *connection)
{
  DBusPreallocatedSend *preallocated;

  _dbus_return_val_if_fail (connection != NULL, NULL);

  CONNECTION_LOCK (connection);
  
  preallocated =
    _dbus_connection_preallocate_send_unlocked (connection);

  CONNECTION_UNLOCK (connection);

  return preallocated;
}

void
dbus_connection_free_preallocated_send (DBusConnection       *connection,
                                        DBusPreallocatedSend *preallocated)
{
  _dbus_return_if_fail (connection != NULL);
  _dbus_return_if_fail (preallocated != NULL);  
  _dbus_return_if_fail (connection == preallocated->connection);

  _dbus_list_free_link (preallocated->queue_link);
  _dbus_counter_unref (preallocated->counter_link->data);
  _dbus_list_free_link (preallocated->counter_link);
  dbus_free (preallocated);
}

/* Called with lock held, does not update dispatch status */
static void
_dbus_connection_send_preallocated_unlocked_no_update (DBusConnection       *connection,
                                                       DBusPreallocatedSend *preallocated,
                                                       DBusMessage          *message,
                                                       dbus_uint32_t        *client_serial)
{
  dbus_uint32_t serial;
  const char *sig;

  preallocated->queue_link->data = message;
  _dbus_list_prepend_link (&connection->outgoing_messages,
                           preallocated->queue_link);

  _dbus_message_add_size_counter_link (message,
                                       preallocated->counter_link);

  dbus_free (preallocated);
  preallocated = NULL;
  
  dbus_message_ref (message);
  
  connection->n_outgoing += 1;

  sig = dbus_message_get_signature (message);
  
  _dbus_verbose ("Message %p (%d %s %s %s '%s') for %s added to outgoing queue %p, %d pending to send\n",
                 message,
                 dbus_message_get_type (message),
                 dbus_message_get_path (message) ?
                 dbus_message_get_path (message) :
                 "no path",
                 dbus_message_get_interface (message) ?
                 dbus_message_get_interface (message) :
                 "no interface",
                 dbus_message_get_member (message) ?
                 dbus_message_get_member (message) :
                 "no member",
                 sig,
                 dbus_message_get_destination (message) ?
                 dbus_message_get_destination (message) :
                 "null",
                 connection,
                 connection->n_outgoing);

  if (dbus_message_get_serial (message) == 0)
    {
      serial = _dbus_connection_get_next_client_serial (connection);
      _dbus_message_set_serial (message, serial);
      if (client_serial)
        *client_serial = serial;
    }
  else
    {
      if (client_serial)
        *client_serial = dbus_message_get_serial (message);
    }

  _dbus_verbose ("Message %p serial is %u\n",
                 message, dbus_message_get_serial (message));
  
  _dbus_message_lock (message);

  /* Now we need to run an iteration to hopefully just write the messages
   * out immediately, and otherwise get them queued up
   */
  _dbus_connection_do_iteration_unlocked (connection,
                                          DBUS_ITERATION_DO_WRITING,
                                          -1);

  /* If stuff is still queued up, be sure we wake up the main loop */
  if (connection->n_outgoing > 0)
    _dbus_connection_wakeup_mainloop (connection);
}

static void
_dbus_connection_send_preallocated_and_unlock (DBusConnection       *connection,
                                               DBusPreallocatedSend *preallocated,
                                               DBusMessage          *message,
                                               dbus_uint32_t        *client_serial)
{
  DBusDispatchStatus status;

  HAVE_LOCK_CHECK (connection);
  
  _dbus_connection_send_preallocated_unlocked_no_update (connection,
                                                         preallocated,
                                                         message, client_serial);

  _dbus_verbose ("%s middle\n", _DBUS_FUNCTION_NAME);
  status = _dbus_connection_get_dispatch_status_unlocked (connection);

  /* this calls out to user code */
  _dbus_connection_update_dispatch_status_and_unlock (connection, status);
}

void
dbus_connection_send_preallocated (DBusConnection       *connection,
                                   DBusPreallocatedSend *preallocated,
                                   DBusMessage          *message,
                                   dbus_uint32_t        *client_serial)
{
  _dbus_return_if_fail (connection != NULL);
  _dbus_return_if_fail (preallocated != NULL);
  _dbus_return_if_fail (message != NULL);
  _dbus_return_if_fail (preallocated->connection == connection);
  _dbus_return_if_fail (dbus_message_get_type (message) != DBUS_MESSAGE_TYPE_METHOD_CALL ||
                        dbus_message_get_member (message) != NULL);
  _dbus_return_if_fail (dbus_message_get_type (message) != DBUS_MESSAGE_TYPE_SIGNAL ||
                        (dbus_message_get_interface (message) != NULL &&
                         dbus_message_get_member (message) != NULL));
  
  CONNECTION_LOCK (connection);
  _dbus_connection_send_preallocated_and_unlock (connection,
                                                 preallocated,
                                                 message, client_serial);
}

static dbus_bool_t
_dbus_connection_send_unlocked_no_update (DBusConnection *connection,
                                          DBusMessage    *message,
                                          dbus_uint32_t  *client_serial)
{
  DBusPreallocatedSend *preallocated;

  _dbus_assert (connection != NULL);
  _dbus_assert (message != NULL);
  
  preallocated = _dbus_connection_preallocate_send_unlocked (connection);
  if (preallocated == NULL)
    return FALSE;

  _dbus_connection_send_preallocated_unlocked_no_update (connection,
                                                         preallocated,
                                                         message,
                                                         client_serial);
  return TRUE;
}

dbus_bool_t
_dbus_connection_send_and_unlock (DBusConnection *connection,
                                  DBusMessage    *message,
                                  dbus_uint32_t  *client_serial)
{
  DBusPreallocatedSend *preallocated;

  _dbus_assert (connection != NULL);
  _dbus_assert (message != NULL);
  
  preallocated = _dbus_connection_preallocate_send_unlocked (connection);
  if (preallocated == NULL)
    {
      CONNECTION_UNLOCK (connection);
      return FALSE;
    }

  _dbus_connection_send_preallocated_and_unlock (connection,
                                                 preallocated,
                                                 message,
                                                 client_serial);
  return TRUE;
}

dbus_bool_t
dbus_connection_send (DBusConnection *connection,
                      DBusMessage    *message,
                      dbus_uint32_t  *client_serial)
{
  _dbus_return_val_if_fail (connection != NULL, FALSE);
  _dbus_return_val_if_fail (message != NULL, FALSE);

  CONNECTION_LOCK (connection);

  return _dbus_connection_send_and_unlock (connection,
                                           message,
                                           client_serial);
}

static dbus_bool_t
reply_handler_timeout (void *data)
{
  DBusConnection *connection;
  DBusDispatchStatus status;
  DBusPendingCall *pending = data;

  connection = pending->connection;
  
  CONNECTION_LOCK (connection);
  if (pending->timeout_link)
    {
      _dbus_connection_queue_synthesized_message_link (connection,
                                                       pending->timeout_link);
      pending->timeout_link = NULL;
    }

  _dbus_connection_remove_timeout_unlocked (connection,
                                            pending->timeout);
  pending->timeout_added = FALSE;

  _dbus_verbose ("%s middle\n", _DBUS_FUNCTION_NAME);
  status = _dbus_connection_get_dispatch_status_unlocked (connection);

  /* Unlocks, and calls out to user code */
  _dbus_connection_update_dispatch_status_and_unlock (connection, status);
  
  return TRUE;
}

dbus_bool_t
dbus_connection_send_with_reply (DBusConnection     *connection,
                                 DBusMessage        *message,
                                 DBusPendingCall   **pending_return,
                                 int                 timeout_milliseconds)
{
  DBusPendingCall *pending;
  DBusMessage *reply;
  DBusList *reply_link;
  dbus_int32_t serial = -1;
  DBusDispatchStatus status;

  _dbus_return_val_if_fail (connection != NULL, FALSE);
  _dbus_return_val_if_fail (message != NULL, FALSE);
  _dbus_return_val_if_fail (timeout_milliseconds >= 0 || timeout_milliseconds == -1, FALSE);

  if (pending_return)
    *pending_return = NULL;
  
  pending = _dbus_pending_call_new (connection,
                                    timeout_milliseconds,
                                    reply_handler_timeout);

  if (pending == NULL)
    return FALSE;

  CONNECTION_LOCK (connection);
  
  /* Assign a serial to the message */
  if (dbus_message_get_serial (message) == 0)
    {
      serial = _dbus_connection_get_next_client_serial (connection);
      _dbus_message_set_serial (message, serial);
    }

  pending->reply_serial = serial;

  reply = dbus_message_new_error (message, DBUS_ERROR_NO_REPLY,
                                  "No reply within specified time");
  if (reply == NULL)
    goto error;

  reply_link = _dbus_list_alloc_link (reply);
  if (reply_link == NULL)
    {
      CONNECTION_UNLOCK (connection);
      dbus_message_unref (reply);
      goto error_unlocked;
    }

  pending->timeout_link = reply_link;

  /* Insert the serial in the pending replies hash;
   * hash takes a refcount on DBusPendingCall.
   * Also, add the timeout.
   */
  if (!_dbus_connection_attach_pending_call_unlocked (connection,
                                                      pending))
    goto error;
 
  if (!_dbus_connection_send_unlocked_no_update (connection, message, NULL))
    {
      _dbus_connection_detach_pending_call_and_unlock (connection,
                                                       pending);
      goto error_unlocked;
    }

  if (pending_return)
    *pending_return = pending;
  else
    {
      _dbus_connection_detach_pending_call_unlocked (connection, pending);
      dbus_pending_call_unref (pending);
    }

  _dbus_verbose ("%s middle\n", _DBUS_FUNCTION_NAME);
  status = _dbus_connection_get_dispatch_status_unlocked (connection);

  /* this calls out to user code */
  _dbus_connection_update_dispatch_status_and_unlock (connection, status);

  return TRUE;

 error:
  CONNECTION_UNLOCK (connection);
 error_unlocked:
  dbus_pending_call_unref (pending);
  return FALSE;
}

/* This is slightly strange since we can pop a message here without
 * the dispatch lock.
 */
static DBusMessage*
check_for_reply_unlocked (DBusConnection *connection,
                          dbus_uint32_t   client_serial)
{
  DBusList *link;

  HAVE_LOCK_CHECK (connection);
  
  link = _dbus_list_get_first_link (&connection->incoming_messages);

  while (link != NULL)
    {
      DBusMessage *reply = link->data;

      if (dbus_message_get_reply_serial (reply) == client_serial)
        {
          _dbus_list_remove_link (&connection->incoming_messages, link);
          connection->n_incoming  -= 1;
          return reply;
        }
      link = _dbus_list_get_next_link (&connection->incoming_messages, link);
    }

  return NULL;
}

static void
_dbus_memory_pause_based_on_timeout (int timeout_milliseconds)
{
  if (timeout_milliseconds == -1)
    _dbus_sleep_milliseconds (1000);
  else if (timeout_milliseconds < 100)
    ; /* just busy loop */
  else if (timeout_milliseconds <= 1000)
    _dbus_sleep_milliseconds (timeout_milliseconds / 3);
  else
    _dbus_sleep_milliseconds (1000);
}

void
_dbus_connection_block_pending_call (DBusPendingCall *pending)
{
  long start_tv_sec, start_tv_usec;
  long end_tv_sec, end_tv_usec;
  long tv_sec, tv_usec;
  DBusDispatchStatus status;
  DBusConnection *connection;
  dbus_uint32_t client_serial;
  int timeout_milliseconds;

  _dbus_assert (pending != NULL);

  if (dbus_pending_call_get_completed (pending))
    return;

  if (pending->connection == NULL)
    return; /* call already detached */

  dbus_pending_call_ref (pending); /* necessary because the call could be canceled */
  
  connection = pending->connection;
  client_serial = pending->reply_serial;

  /* note that timeout_milliseconds is limited to a smallish value
   * in _dbus_pending_call_new() so overflows aren't possible
   * below
   */
  timeout_milliseconds = dbus_timeout_get_interval (pending->timeout);

  /* Flush message queue */
  dbus_connection_flush (connection);

  CONNECTION_LOCK (connection);

  _dbus_get_current_time (&start_tv_sec, &start_tv_usec);
  end_tv_sec = start_tv_sec + timeout_milliseconds / 1000;
  end_tv_usec = start_tv_usec + (timeout_milliseconds % 1000) * 1000;
  end_tv_sec += end_tv_usec / _DBUS_USEC_PER_SECOND;
  end_tv_usec = end_tv_usec % _DBUS_USEC_PER_SECOND;

  _dbus_verbose ("dbus_connection_send_with_reply_and_block(): will block %d milliseconds for reply serial %u from %ld sec %ld usec to %ld sec %ld usec\n",
                 timeout_milliseconds,
                 client_serial,
                 start_tv_sec, start_tv_usec,
                 end_tv_sec, end_tv_usec);

  /* Now we wait... */
  /* always block at least once as we know we don't have the reply yet */
  _dbus_connection_do_iteration_unlocked (connection,
                                          DBUS_ITERATION_DO_READING |
                                          DBUS_ITERATION_BLOCK,
                                          timeout_milliseconds);

 recheck_status:

  _dbus_verbose ("%s top of recheck\n", _DBUS_FUNCTION_NAME);
  
  HAVE_LOCK_CHECK (connection);
  
  /* queue messages and get status */

  status = _dbus_connection_get_dispatch_status_unlocked (connection);

  /* the get_completed() is in case a dispatch() while we were blocking
   * got the reply instead of us.
   */
  if (dbus_pending_call_get_completed (pending))
    {
      _dbus_verbose ("Pending call completed by dispatch in %s\n", _DBUS_FUNCTION_NAME);
      _dbus_connection_update_dispatch_status_and_unlock (connection, status);
      dbus_pending_call_unref (pending);
      return;
    }
  
  if (status == DBUS_DISPATCH_DATA_REMAINS)
    {
      DBusMessage *reply;
      
      reply = check_for_reply_unlocked (connection, client_serial);
      if (reply != NULL)
        {
          _dbus_verbose ("%s checked for reply\n", _DBUS_FUNCTION_NAME);

          _dbus_verbose ("dbus_connection_send_with_reply_and_block(): got reply\n");
          
          _dbus_pending_call_complete_and_unlock (pending, reply);
          dbus_message_unref (reply);

          CONNECTION_LOCK (connection);
          status = _dbus_connection_get_dispatch_status_unlocked (connection);
          _dbus_connection_update_dispatch_status_and_unlock (connection, status);
          dbus_pending_call_unref (pending);
          
          return;
        }
    }
  
  _dbus_get_current_time (&tv_sec, &tv_usec);
  
  if (!_dbus_connection_get_is_connected_unlocked (connection))
    {
      /* FIXME send a "DBUS_ERROR_DISCONNECTED" instead, just to help
       * programmers understand what went wrong since the timeout is
       * confusing
       */
      
      _dbus_pending_call_complete_and_unlock (pending, NULL);
      dbus_pending_call_unref (pending);
      return;
    }
  else if (tv_sec < start_tv_sec)
    _dbus_verbose ("dbus_connection_send_with_reply_and_block(): clock set backward\n");
  else if (connection->disconnect_message_link == NULL)
    _dbus_verbose ("dbus_connection_send_with_reply_and_block(): disconnected\n");
  else if (tv_sec < end_tv_sec ||
           (tv_sec == end_tv_sec && tv_usec < end_tv_usec))
    {
      timeout_milliseconds = (end_tv_sec - tv_sec) * 1000 +
        (end_tv_usec - tv_usec) / 1000;
      _dbus_verbose ("dbus_connection_send_with_reply_and_block(): %d milliseconds remain\n", timeout_milliseconds);
      _dbus_assert (timeout_milliseconds >= 0);
      
      if (status == DBUS_DISPATCH_NEED_MEMORY)
        {
          /* Try sleeping a bit, as we aren't sure we need to block for reading,
           * we may already have a reply in the buffer and just can't process
           * it.
           */
          _dbus_verbose ("dbus_connection_send_with_reply_and_block() waiting for more memory\n");

          _dbus_memory_pause_based_on_timeout (timeout_milliseconds);
        }
      else
        {          
          /* block again, we don't have the reply buffered yet. */
          _dbus_connection_do_iteration_unlocked (connection,
                                                  DBUS_ITERATION_DO_READING |
                                                  DBUS_ITERATION_BLOCK,
                                                  timeout_milliseconds);
        }

      goto recheck_status;
    }

  _dbus_verbose ("dbus_connection_send_with_reply_and_block(): Waited %ld milliseconds and got no reply\n",
                 (tv_sec - start_tv_sec) * 1000 + (tv_usec - start_tv_usec) / 1000);

  _dbus_assert (!dbus_pending_call_get_completed (pending));
  
  /* unlock and call user code */
  _dbus_pending_call_complete_and_unlock (pending, NULL);

  /* update user code on dispatch status */
  CONNECTION_LOCK (connection);
  status = _dbus_connection_get_dispatch_status_unlocked (connection);
  _dbus_connection_update_dispatch_status_and_unlock (connection, status);
  dbus_pending_call_unref (pending);
}

DBusMessage*
dbus_connection_send_with_reply_and_block (DBusConnection     *connection,
                                           DBusMessage        *message,
                                           int                 timeout_milliseconds,
                                           DBusError          *error)
{
  DBusMessage *reply;
  DBusPendingCall *pending;
  
  _dbus_return_val_if_fail (connection != NULL, NULL);
  _dbus_return_val_if_fail (message != NULL, NULL);
  _dbus_return_val_if_fail (timeout_milliseconds >= 0 || timeout_milliseconds == -1, NULL);
  _dbus_return_val_if_error_is_set (error, NULL);
  
  if (!dbus_connection_send_with_reply (connection, message,
                                        &pending, timeout_milliseconds))
    {
      _DBUS_SET_OOM (error);
      return NULL;
    }

  _dbus_assert (pending != NULL);
  
  dbus_pending_call_block (pending);

  reply = dbus_pending_call_steal_reply (pending);
  dbus_pending_call_unref (pending);

  /* call_complete_and_unlock() called from pending_call_block() should
   * always fill this in.
   */
  _dbus_assert (reply != NULL);
  
   if (dbus_set_error_from_message (error, reply))
    {
      dbus_message_unref (reply);
      return NULL;
    }
  else
    return reply;
}

void
dbus_connection_flush (DBusConnection *connection)
{
  /* We have to specify DBUS_ITERATION_DO_READING here because
   * otherwise we could have two apps deadlock if they are both doing
   * a flush(), and the kernel buffers fill up. This could change the
   * dispatch status.
   */
  DBusDispatchStatus status;

  _dbus_return_if_fail (connection != NULL);
  
  CONNECTION_LOCK (connection);
  while (connection->n_outgoing > 0 &&
         _dbus_connection_get_is_connected_unlocked (connection))
    {
      _dbus_verbose ("doing iteration in %s\n", _DBUS_FUNCTION_NAME);
      HAVE_LOCK_CHECK (connection);
      _dbus_connection_do_iteration_unlocked (connection,
                                              DBUS_ITERATION_DO_READING |
                                              DBUS_ITERATION_DO_WRITING |
                                              DBUS_ITERATION_BLOCK,
                                              -1);
    }

  HAVE_LOCK_CHECK (connection);
  _dbus_verbose ("%s middle\n", _DBUS_FUNCTION_NAME);
  status = _dbus_connection_get_dispatch_status_unlocked (connection);

  HAVE_LOCK_CHECK (connection);
  /* Unlocks and calls out to user code */
  _dbus_connection_update_dispatch_status_and_unlock (connection, status);

  _dbus_verbose ("%s end\n", _DBUS_FUNCTION_NAME);
}

dbus_bool_t
_dbus_connection_read_write_dispatch (DBusConnection *connection,
                                     int             timeout_milliseconds, 
                                     dbus_bool_t     dispatch)
{
  DBusDispatchStatus dstatus;
  dbus_bool_t dispatched_disconnected;
  
  _dbus_return_val_if_fail (connection != NULL, FALSE);
  _dbus_return_val_if_fail (timeout_milliseconds >= 0 || timeout_milliseconds == -1, FALSE);
  dstatus = dbus_connection_get_dispatch_status (connection);

  if (dispatch && dstatus == DBUS_DISPATCH_DATA_REMAINS)
    {
      _dbus_verbose ("doing dispatch in %s\n", _DBUS_FUNCTION_NAME);
      dbus_connection_dispatch (connection);
      CONNECTION_LOCK (connection);
    }
  else if (dstatus == DBUS_DISPATCH_NEED_MEMORY)
    {
      _dbus_verbose ("pausing for memory in %s\n", _DBUS_FUNCTION_NAME);
      _dbus_memory_pause_based_on_timeout (timeout_milliseconds);
      CONNECTION_LOCK (connection);
    }
  else
    {
      CONNECTION_LOCK (connection);
      if (_dbus_connection_get_is_connected_unlocked (connection))
        {
          _dbus_verbose ("doing iteration in %s\n", _DBUS_FUNCTION_NAME);
          _dbus_connection_do_iteration_unlocked (connection,
                                                  DBUS_ITERATION_DO_READING |
                                                  DBUS_ITERATION_DO_WRITING |
                                                  DBUS_ITERATION_BLOCK,
                                                  timeout_milliseconds);
        }
    }
  
  HAVE_LOCK_CHECK (connection);
  dispatched_disconnected = connection->n_incoming == 0 &&
    connection->disconnect_message_link == NULL;
  CONNECTION_UNLOCK (connection);
  return !dispatched_disconnected; /* TRUE if we have not processed disconnected */
}


dbus_bool_t
dbus_connection_read_write_dispatch (DBusConnection *connection,
                                     int             timeout_milliseconds)
{
   return _dbus_connection_read_write_dispatch(connection, timeout_milliseconds, TRUE);
}

dbus_bool_t 
dbus_connection_read_write (DBusConnection *connection, 
                            int             timeout_milliseconds) 
{ 
   return _dbus_connection_read_write_dispatch(connection, timeout_milliseconds, FALSE);
}

DBusMessage*
dbus_connection_borrow_message (DBusConnection *connection)
{
  DBusDispatchStatus status;
  DBusMessage *message;

  _dbus_return_val_if_fail (connection != NULL, NULL);

  _dbus_verbose ("%s start\n", _DBUS_FUNCTION_NAME);
  
  /* this is called for the side effect that it queues
   * up any messages from the transport
   */
  status = dbus_connection_get_dispatch_status (connection);
  if (status != DBUS_DISPATCH_DATA_REMAINS)
    return NULL;
  
  CONNECTION_LOCK (connection);

  _dbus_connection_acquire_dispatch (connection);

  /* While a message is outstanding, the dispatch lock is held */
  _dbus_assert (connection->message_borrowed == NULL);

  connection->message_borrowed = _dbus_list_get_first (&connection->incoming_messages);
  
  message = connection->message_borrowed;

  /* Note that we KEEP the dispatch lock until the message is returned */
  if (message == NULL)
    _dbus_connection_release_dispatch (connection);

  CONNECTION_UNLOCK (connection);
  
  return message;
}

void
dbus_connection_return_message (DBusConnection *connection,
                                DBusMessage    *message)
{
  _dbus_return_if_fail (connection != NULL);
  _dbus_return_if_fail (message != NULL);
  _dbus_return_if_fail (message == connection->message_borrowed);
  _dbus_return_if_fail (connection->dispatch_acquired);
  
  CONNECTION_LOCK (connection);
  
  _dbus_assert (message == connection->message_borrowed);
  
  connection->message_borrowed = NULL;

  _dbus_connection_release_dispatch (connection);
  
  CONNECTION_UNLOCK (connection);
}

void
dbus_connection_steal_borrowed_message (DBusConnection *connection,
                                        DBusMessage    *message)
{
  DBusMessage *pop_message;

  _dbus_return_if_fail (connection != NULL);
  _dbus_return_if_fail (message != NULL);
  _dbus_return_if_fail (message == connection->message_borrowed);
  _dbus_return_if_fail (connection->dispatch_acquired);
  
  CONNECTION_LOCK (connection);
 
  _dbus_assert (message == connection->message_borrowed);

  pop_message = _dbus_list_pop_first (&connection->incoming_messages);
  _dbus_assert (message == pop_message);
  
  connection->n_incoming -= 1;
 
  _dbus_verbose ("Incoming message %p stolen from queue, %d incoming\n",
                 message, connection->n_incoming);
 
  connection->message_borrowed = NULL;

  _dbus_connection_release_dispatch (connection);
  
  CONNECTION_UNLOCK (connection);
}

/* See dbus_connection_pop_message, but requires the caller to own
 * the lock before calling. May drop the lock while running.
 */
static DBusList*
_dbus_connection_pop_message_link_unlocked (DBusConnection *connection)
{
  HAVE_LOCK_CHECK (connection);
  
  _dbus_assert (connection->message_borrowed == NULL);
  
  if (connection->n_incoming > 0)
    {
      DBusList *link;

      link = _dbus_list_pop_first_link (&connection->incoming_messages);
      connection->n_incoming -= 1;

      _dbus_verbose ("Message %p (%d %s %s %s '%s') removed from incoming queue %p, %d incoming\n",
                     link->data,
                     dbus_message_get_type (link->data),
                     dbus_message_get_path (link->data) ?
                     dbus_message_get_path (link->data) :
                     "no path",
                     dbus_message_get_interface (link->data) ?
                     dbus_message_get_interface (link->data) :
                     "no interface",
                     dbus_message_get_member (link->data) ?
                     dbus_message_get_member (link->data) :
                     "no member",
                     dbus_message_get_signature (link->data),
                     connection, connection->n_incoming);

      return link;
    }
  else
    return NULL;
}

/* See dbus_connection_pop_message, but requires the caller to own
 * the lock before calling. May drop the lock while running.
 */
static DBusMessage*
_dbus_connection_pop_message_unlocked (DBusConnection *connection)
{
  DBusList *link;

  HAVE_LOCK_CHECK (connection);
  
  link = _dbus_connection_pop_message_link_unlocked (connection);

  if (link != NULL)
    {
      DBusMessage *message;
      
      message = link->data;
      
      _dbus_list_free_link (link);
      
      return message;
    }
  else
    return NULL;
}

static void
_dbus_connection_putback_message_link_unlocked (DBusConnection *connection,
                                                DBusList       *message_link)
{
  HAVE_LOCK_CHECK (connection);
  
  _dbus_assert (message_link != NULL);
  /* You can't borrow a message while a link is outstanding */
  _dbus_assert (connection->message_borrowed == NULL);
  /* We had to have the dispatch lock across the pop/putback */
  _dbus_assert (connection->dispatch_acquired);

  _dbus_list_prepend_link (&connection->incoming_messages,
                           message_link);
  connection->n_incoming += 1;

  _dbus_verbose ("Message %p (%d %s %s '%s') put back into queue %p, %d incoming\n",
                 message_link->data,
                 dbus_message_get_type (message_link->data),
                 dbus_message_get_interface (message_link->data) ?
                 dbus_message_get_interface (message_link->data) :
                 "no interface",
                 dbus_message_get_member (message_link->data) ?
                 dbus_message_get_member (message_link->data) :
                 "no member",
                 dbus_message_get_signature (message_link->data),
                 connection, connection->n_incoming);
}

DBusMessage*
dbus_connection_pop_message (DBusConnection *connection)
{
  DBusMessage *message;
  DBusDispatchStatus status;

  _dbus_verbose ("%s start\n", _DBUS_FUNCTION_NAME);
  
  /* this is called for the side effect that it queues
   * up any messages from the transport
   */
  status = dbus_connection_get_dispatch_status (connection);
  if (status != DBUS_DISPATCH_DATA_REMAINS)
    return NULL;
  
  CONNECTION_LOCK (connection);
  _dbus_connection_acquire_dispatch (connection);
  HAVE_LOCK_CHECK (connection);
  
  message = _dbus_connection_pop_message_unlocked (connection);

  _dbus_verbose ("Returning popped message %p\n", message);    

  _dbus_connection_release_dispatch (connection);
  CONNECTION_UNLOCK (connection);
  
  return message;
}

static void
_dbus_connection_acquire_dispatch (DBusConnection *connection)
{
  HAVE_LOCK_CHECK (connection);

  _dbus_connection_ref_unlocked (connection);
  CONNECTION_UNLOCK (connection);
  
  _dbus_verbose ("%s locking dispatch_mutex\n", _DBUS_FUNCTION_NAME);
  _dbus_mutex_lock (connection->dispatch_mutex);

  while (connection->dispatch_acquired)
    {
      _dbus_verbose ("%s waiting for dispatch to be acquirable\n", _DBUS_FUNCTION_NAME);
      _dbus_condvar_wait (connection->dispatch_cond, connection->dispatch_mutex);
    }
  
  _dbus_assert (!connection->dispatch_acquired);

  connection->dispatch_acquired = TRUE;

  _dbus_verbose ("%s unlocking dispatch_mutex\n", _DBUS_FUNCTION_NAME);
  _dbus_mutex_unlock (connection->dispatch_mutex);
  
  CONNECTION_LOCK (connection);
  _dbus_connection_unref_unlocked (connection);
}

static void
_dbus_connection_release_dispatch (DBusConnection *connection)
{
  HAVE_LOCK_CHECK (connection);
  
  _dbus_verbose ("%s locking dispatch_mutex\n", _DBUS_FUNCTION_NAME);
  _dbus_mutex_lock (connection->dispatch_mutex);
  
  _dbus_assert (connection->dispatch_acquired);

  connection->dispatch_acquired = FALSE;
  _dbus_condvar_wake_one (connection->dispatch_cond);

  _dbus_verbose ("%s unlocking dispatch_mutex\n", _DBUS_FUNCTION_NAME);
  _dbus_mutex_unlock (connection->dispatch_mutex);
}

static void
_dbus_connection_failed_pop (DBusConnection *connection,
                             DBusList       *message_link)
{
  _dbus_list_prepend_link (&connection->incoming_messages,
                           message_link);
  connection->n_incoming += 1;
}

static DBusDispatchStatus
_dbus_connection_get_dispatch_status_unlocked (DBusConnection *connection)
{
  HAVE_LOCK_CHECK (connection);
  
  if (connection->n_incoming > 0)
    return DBUS_DISPATCH_DATA_REMAINS;
  else if (!_dbus_transport_queue_messages (connection->transport))
    return DBUS_DISPATCH_NEED_MEMORY;
  else
    {
      DBusDispatchStatus status;
      dbus_bool_t is_connected;
      
      status = _dbus_transport_get_dispatch_status (connection->transport);
      is_connected = _dbus_transport_get_is_connected (connection->transport);

      _dbus_verbose ("dispatch status = %s is_connected = %d\n",
                     DISPATCH_STATUS_NAME (status), is_connected);
      
      if (!is_connected)
        {
          if (status == DBUS_DISPATCH_COMPLETE &&
              connection->disconnect_message_link)
            {
              _dbus_verbose ("Sending disconnect message from %s\n",
                             _DBUS_FUNCTION_NAME);

              connection_forget_shared_unlocked (connection);
              
              /* We haven't sent the disconnect message already,
               * and all real messages have been queued up.
               */
              _dbus_connection_queue_synthesized_message_link (connection,
                                                               connection->disconnect_message_link);
              connection->disconnect_message_link = NULL;

              status = DBUS_DISPATCH_DATA_REMAINS;
            }

          /* Dump the outgoing queue, we aren't going to be able to
           * send it now, and we'd like accessors like
           * dbus_connection_get_outgoing_size() to be accurate.
           */
          if (connection->n_outgoing > 0)
            {
              DBusList *link;
              
              _dbus_verbose ("Dropping %d outgoing messages since we're disconnected\n",
                             connection->n_outgoing);
              
              while ((link = _dbus_list_get_last_link (&connection->outgoing_messages)))
                {
                  _dbus_connection_message_sent (connection, link->data);
                }
            }
        }
      
      if (status != DBUS_DISPATCH_COMPLETE)
        return status;
      else if (connection->n_incoming > 0)
        return DBUS_DISPATCH_DATA_REMAINS;
      else
        return DBUS_DISPATCH_COMPLETE;
    }
}

static void
_dbus_connection_update_dispatch_status_and_unlock (DBusConnection    *connection,
                                                    DBusDispatchStatus new_status)
{
  dbus_bool_t changed;
  DBusDispatchStatusFunction function;
  void *data;

  HAVE_LOCK_CHECK (connection);

  _dbus_connection_ref_unlocked (connection);

  changed = new_status != connection->last_dispatch_status;

  connection->last_dispatch_status = new_status;

  function = connection->dispatch_status_function;
  data = connection->dispatch_status_data;

  /* We drop the lock */
  CONNECTION_UNLOCK (connection);
  
  if (changed && function)
    {
      _dbus_verbose ("Notifying of change to dispatch status of %p now %d (%s)\n",
                     connection, new_status,
                     DISPATCH_STATUS_NAME (new_status));
      (* function) (connection, new_status, data);      
    }
  
  dbus_connection_unref (connection);
}

DBusDispatchStatus
dbus_connection_get_dispatch_status (DBusConnection *connection)
{
  DBusDispatchStatus status;

  _dbus_return_val_if_fail (connection != NULL, DBUS_DISPATCH_COMPLETE);

  _dbus_verbose ("%s start\n", _DBUS_FUNCTION_NAME);
  
  CONNECTION_LOCK (connection);

  status = _dbus_connection_get_dispatch_status_unlocked (connection);
  
  CONNECTION_UNLOCK (connection);

  return status;
}

static DBusHandlerResult
_dbus_connection_peer_filter_unlocked_no_update (DBusConnection *connection,
                                                 DBusMessage    *message)
{
  if (dbus_message_is_method_call (message,
                                   DBUS_INTERFACE_PEER,
                                   "Ping"))
    {
      DBusMessage *ret;
      dbus_bool_t sent;
      
      ret = dbus_message_new_method_return (message);
      if (ret == NULL)
        return DBUS_HANDLER_RESULT_NEED_MEMORY;
     
      sent = _dbus_connection_send_unlocked_no_update (connection, ret, NULL);

      dbus_message_unref (ret);

      if (!sent)
        return DBUS_HANDLER_RESULT_NEED_MEMORY;
      
      return DBUS_HANDLER_RESULT_HANDLED;
    }
                                   
  
  return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
}

static DBusHandlerResult
_dbus_connection_run_builtin_filters_unlocked_no_update (DBusConnection *connection,
                                                           DBusMessage    *message)
{
  /* We just run one filter for now but have the option to run more
     if the spec calls for it in the future */

  return _dbus_connection_peer_filter_unlocked_no_update (connection, message);
}

DBusDispatchStatus
dbus_connection_dispatch (DBusConnection *connection)
{
  DBusMessage *message;
  DBusList *link, *filter_list_copy, *message_link;
  DBusHandlerResult result;
  DBusPendingCall *pending;
  dbus_int32_t reply_serial;
  DBusDispatchStatus status;

  _dbus_return_val_if_fail (connection != NULL, DBUS_DISPATCH_COMPLETE);

  _dbus_verbose ("%s\n", _DBUS_FUNCTION_NAME);
  
  CONNECTION_LOCK (connection);
  status = _dbus_connection_get_dispatch_status_unlocked (connection);
  if (status != DBUS_DISPATCH_DATA_REMAINS)
    {
      /* unlocks and calls out to user code */
      _dbus_connection_update_dispatch_status_and_unlock (connection, status);
      return status;
    }
  
  /* We need to ref the connection since the callback could potentially
   * drop the last ref to it
   */
  _dbus_connection_ref_unlocked (connection);

  _dbus_connection_acquire_dispatch (connection);
  HAVE_LOCK_CHECK (connection);

  message_link = _dbus_connection_pop_message_link_unlocked (connection);
  if (message_link == NULL)
    {
      /* another thread dispatched our stuff */

      _dbus_verbose ("another thread dispatched message (during acquire_dispatch above)\n");
      
      _dbus_connection_release_dispatch (connection);

      status = _dbus_connection_get_dispatch_status_unlocked (connection);

      _dbus_connection_update_dispatch_status_and_unlock (connection, status);
      
      dbus_connection_unref (connection);
      
      return status;
    }

  message = message_link->data;

  _dbus_verbose (" dispatching message %p (%d %s %s '%s')\n",
                 message,
                 dbus_message_get_type (message),
                 dbus_message_get_interface (message) ?
                 dbus_message_get_interface (message) :
                 "no interface",
                 dbus_message_get_member (message) ?
                 dbus_message_get_member (message) :
                 "no member",
                 dbus_message_get_signature (message));

  result = DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
  
  /* Pending call handling must be first, because if you do
   * dbus_connection_send_with_reply_and_block() or
   * dbus_pending_call_block() then no handlers/filters will be run on
   * the reply. We want consistent semantics in the case where we
   * dbus_connection_dispatch() the reply.
   */
  
  reply_serial = dbus_message_get_reply_serial (message);
  pending = _dbus_hash_table_lookup_int (connection->pending_replies,
                                         reply_serial);
  if (pending)
    {
      _dbus_verbose ("Dispatching a pending reply\n");
      _dbus_pending_call_complete_and_unlock (pending, message);
      pending = NULL; /* it's probably unref'd */
      
      CONNECTION_LOCK (connection);
      _dbus_verbose ("pending call completed in dispatch\n");
      result = DBUS_HANDLER_RESULT_HANDLED;
      goto out;
    }

  result = _dbus_connection_run_builtin_filters_unlocked_no_update (connection, message);
  if (result != DBUS_HANDLER_RESULT_NOT_YET_HANDLED)
    goto out;
 
  if (!_dbus_list_copy (&connection->filter_list, &filter_list_copy))
    {
      _dbus_connection_release_dispatch (connection);
      HAVE_LOCK_CHECK (connection);
      
      _dbus_connection_failed_pop (connection, message_link);

      /* unlocks and calls user code */
      _dbus_connection_update_dispatch_status_and_unlock (connection,
                                                          DBUS_DISPATCH_NEED_MEMORY);

      if (pending)
        dbus_pending_call_unref (pending);
      dbus_connection_unref (connection);
      
      return DBUS_DISPATCH_NEED_MEMORY;
    }
  
  _dbus_list_foreach (&filter_list_copy,
                      (DBusForeachFunction)_dbus_message_filter_ref,
                      NULL);

  /* We're still protected from dispatch() reentrancy here
   * since we acquired the dispatcher
   */
  CONNECTION_UNLOCK (connection);
  
  link = _dbus_list_get_first_link (&filter_list_copy);
  while (link != NULL)
    {
      DBusMessageFilter *filter = link->data;
      DBusList *next = _dbus_list_get_next_link (&filter_list_copy, link);

      _dbus_verbose ("  running filter on message %p\n", message);
      result = (* filter->function) (connection, message, filter->user_data);

      if (result != DBUS_HANDLER_RESULT_NOT_YET_HANDLED)
        break;

      link = next;
    }

  _dbus_list_foreach (&filter_list_copy,
                      (DBusForeachFunction)_dbus_message_filter_unref,
                      NULL);
  _dbus_list_clear (&filter_list_copy);
  
  CONNECTION_LOCK (connection);

  if (result == DBUS_HANDLER_RESULT_NEED_MEMORY)
    {
      _dbus_verbose ("No memory in %s\n", _DBUS_FUNCTION_NAME);
      goto out;
    }
  else if (result == DBUS_HANDLER_RESULT_HANDLED)
    {
      _dbus_verbose ("filter handled message in dispatch\n");
      goto out;
    }

  /* We're still protected from dispatch() reentrancy here
   * since we acquired the dispatcher
   */
  _dbus_verbose ("  running object path dispatch on message %p (%d %s %s '%s')\n",
                 message,
                 dbus_message_get_type (message),
                 dbus_message_get_interface (message) ?
                 dbus_message_get_interface (message) :
                 "no interface",
                 dbus_message_get_member (message) ?
                 dbus_message_get_member (message) :
                 "no member",
                 dbus_message_get_signature (message));

  HAVE_LOCK_CHECK (connection);
  result = _dbus_object_tree_dispatch_and_unlock (connection->objects,
                                                  message);
  
  CONNECTION_LOCK (connection);

  if (result != DBUS_HANDLER_RESULT_NOT_YET_HANDLED)
    {
      _dbus_verbose ("object tree handled message in dispatch\n");
      goto out;
    }

  if (dbus_message_get_type (message) == DBUS_MESSAGE_TYPE_METHOD_CALL)
    {
      DBusMessage *reply;
      DBusString str;
      DBusPreallocatedSend *preallocated;

      _dbus_verbose ("  sending error %s\n",
                     DBUS_ERROR_UNKNOWN_METHOD);
      
      if (!_dbus_string_init (&str))
        {
          result = DBUS_HANDLER_RESULT_NEED_MEMORY;
          _dbus_verbose ("no memory for error string in dispatch\n");
          goto out;
        }
              
      if (!_dbus_string_append_printf (&str,
                                       "Method \"%s\" with signature \"%s\" on interface \"%s\" doesn't exist\n",
                                       dbus_message_get_member (message),
                                       dbus_message_get_signature (message),
                                       dbus_message_get_interface (message)))
        {
          _dbus_string_free (&str);
          result = DBUS_HANDLER_RESULT_NEED_MEMORY;
          _dbus_verbose ("no memory for error string in dispatch\n");
          goto out;
        }
      
      reply = dbus_message_new_error (message,
                                      DBUS_ERROR_UNKNOWN_METHOD,
                                      _dbus_string_get_const_data (&str));
      _dbus_string_free (&str);

      if (reply == NULL)
        {
          result = DBUS_HANDLER_RESULT_NEED_MEMORY;
          _dbus_verbose ("no memory for error reply in dispatch\n");
          goto out;
        }
      
      preallocated = _dbus_connection_preallocate_send_unlocked (connection);

      if (preallocated == NULL)
        {
          dbus_message_unref (reply);
          result = DBUS_HANDLER_RESULT_NEED_MEMORY;
          _dbus_verbose ("no memory for error send in dispatch\n");
          goto out;
        }

      _dbus_connection_send_preallocated_unlocked_no_update (connection, preallocated,
                                                             reply, NULL);

      dbus_message_unref (reply);
      
      result = DBUS_HANDLER_RESULT_HANDLED;
    }
  
  _dbus_verbose ("  done dispatching %p (%d %s %s '%s') on connection %p\n", message,
                 dbus_message_get_type (message),
                 dbus_message_get_interface (message) ?
                 dbus_message_get_interface (message) :
                 "no interface",
                 dbus_message_get_member (message) ?
                 dbus_message_get_member (message) :
                 "no member",
                 dbus_message_get_signature (message),
                 connection);
  
 out:
  if (result == DBUS_HANDLER_RESULT_NEED_MEMORY)
    {
      _dbus_verbose ("out of memory in %s\n", _DBUS_FUNCTION_NAME);
      
      /* Put message back, and we'll start over.
       * Yes this means handlers must be idempotent if they
       * don't return HANDLED; c'est la vie.
       */
      _dbus_connection_putback_message_link_unlocked (connection,
                                                      message_link);
    }
  else
    {
      _dbus_verbose (" ... done dispatching in %s\n", _DBUS_FUNCTION_NAME);
      
      if (connection->exit_on_disconnect &&
          dbus_message_is_signal (message,
                                  DBUS_INTERFACE_LOCAL,
                                  "Disconnected"))
        {
          _dbus_verbose ("Exiting on Disconnected signal\n");
          CONNECTION_UNLOCK (connection);
          _dbus_exit (1);
          _dbus_assert_not_reached ("Call to exit() returned");
        }
      
      _dbus_list_free_link (message_link);
      dbus_message_unref (message); /* don't want the message to count in max message limits
                                     * in computing dispatch status below
                                     */
    }
  
  _dbus_connection_release_dispatch (connection);
  HAVE_LOCK_CHECK (connection);

  _dbus_verbose ("%s before final status update\n", _DBUS_FUNCTION_NAME);
  status = _dbus_connection_get_dispatch_status_unlocked (connection);

  /* unlocks and calls user code */
  _dbus_connection_update_dispatch_status_and_unlock (connection, status);
  
  dbus_connection_unref (connection);
  
  return status;
}

dbus_bool_t
dbus_connection_set_watch_functions (DBusConnection              *connection,
                                     DBusAddWatchFunction         add_function,
                                     DBusRemoveWatchFunction      remove_function,
                                     DBusWatchToggledFunction     toggled_function,
                                     void                        *data,
                                     DBusFreeFunction             free_data_function)
{
  dbus_bool_t retval;
  DBusWatchList *watches;

  _dbus_return_val_if_fail (connection != NULL, FALSE);
  
  CONNECTION_LOCK (connection);

#ifndef DBUS_DISABLE_CHECKS
  if (connection->watches == NULL)
    {
      _dbus_warn ("Re-entrant call to %s is not allowed\n",
                  _DBUS_FUNCTION_NAME);
      return FALSE;
    }
#endif
  
  /* ref connection for slightly better reentrancy */
  _dbus_connection_ref_unlocked (connection);

  /* This can call back into user code, and we need to drop the
   * connection lock when it does. This is kind of a lame
   * way to do it.
   */
  watches = connection->watches;
  connection->watches = NULL;
  CONNECTION_UNLOCK (connection);

  retval = _dbus_watch_list_set_functions (watches,
                                           add_function, remove_function,
                                           toggled_function,
                                           data, free_data_function);
  CONNECTION_LOCK (connection);
  connection->watches = watches;
  
  CONNECTION_UNLOCK (connection);
  /* drop our paranoid refcount */
  dbus_connection_unref (connection);
  
  return retval;
}

dbus_bool_t
dbus_connection_set_timeout_functions   (DBusConnection            *connection,
                                         DBusAddTimeoutFunction     add_function,
                                         DBusRemoveTimeoutFunction  remove_function,
                                         DBusTimeoutToggledFunction toggled_function,
                                         void                      *data,
                                         DBusFreeFunction           free_data_function)
{
  dbus_bool_t retval;
  DBusTimeoutList *timeouts;

  _dbus_return_val_if_fail (connection != NULL, FALSE);
  
  CONNECTION_LOCK (connection);

#ifndef DBUS_DISABLE_CHECKS
  if (connection->timeouts == NULL)
    {
      _dbus_warn ("Re-entrant call to %s is not allowed\n",
                  _DBUS_FUNCTION_NAME);
      return FALSE;
    }
#endif
  
  /* ref connection for slightly better reentrancy */
  _dbus_connection_ref_unlocked (connection);

  timeouts = connection->timeouts;
  connection->timeouts = NULL;
  CONNECTION_UNLOCK (connection);
  
  retval = _dbus_timeout_list_set_functions (timeouts,
                                             add_function, remove_function,
                                             toggled_function,
                                             data, free_data_function);
  CONNECTION_LOCK (connection);
  connection->timeouts = timeouts;
  
  CONNECTION_UNLOCK (connection);
  /* drop our paranoid refcount */
  dbus_connection_unref (connection);

  return retval;
}

void
dbus_connection_set_wakeup_main_function (DBusConnection            *connection,
                                          DBusWakeupMainFunction     wakeup_main_function,
                                          void                      *data,
                                          DBusFreeFunction           free_data_function)
{
  void *old_data;
  DBusFreeFunction old_free_data;

  _dbus_return_if_fail (connection != NULL);
  
  CONNECTION_LOCK (connection);
  old_data = connection->wakeup_main_data;
  old_free_data = connection->free_wakeup_main_data;

  connection->wakeup_main_function = wakeup_main_function;
  connection->wakeup_main_data = data;
  connection->free_wakeup_main_data = free_data_function;
  
  CONNECTION_UNLOCK (connection);

  /* Callback outside the lock */
  if (old_free_data)
    (*old_free_data) (old_data);
}

void
dbus_connection_set_dispatch_status_function (DBusConnection             *connection,
                                              DBusDispatchStatusFunction  function,
                                              void                       *data,
                                              DBusFreeFunction            free_data_function)
{
  void *old_data;
  DBusFreeFunction old_free_data;

  _dbus_return_if_fail (connection != NULL);
  
  CONNECTION_LOCK (connection);
  old_data = connection->dispatch_status_data;
  old_free_data = connection->free_dispatch_status_data;

  connection->dispatch_status_function = function;
  connection->dispatch_status_data = data;
  connection->free_dispatch_status_data = free_data_function;
  
  CONNECTION_UNLOCK (connection);

  /* Callback outside the lock */
  if (old_free_data)
    (*old_free_data) (old_data);
}

dbus_bool_t
dbus_connection_get_unix_fd (DBusConnection *connection,
                             int            *fd)
{
  dbus_bool_t retval;

  _dbus_return_val_if_fail (connection != NULL, FALSE);
  _dbus_return_val_if_fail (connection->transport != NULL, FALSE);
  
  CONNECTION_LOCK (connection);
  
  retval = _dbus_transport_get_unix_fd (connection->transport,
                                        fd);

  CONNECTION_UNLOCK (connection);

  return retval;
}

dbus_bool_t
dbus_connection_get_unix_user (DBusConnection *connection,
                               unsigned long  *uid)
{
  dbus_bool_t result;

  _dbus_return_val_if_fail (connection != NULL, FALSE);
  _dbus_return_val_if_fail (uid != NULL, FALSE);
  
  CONNECTION_LOCK (connection);

  if (!_dbus_transport_get_is_authenticated (connection->transport))
    result = FALSE;
  else
    result = _dbus_transport_get_unix_user (connection->transport,
                                            uid);
  CONNECTION_UNLOCK (connection);

  return result;
}

dbus_bool_t
dbus_connection_get_unix_process_id (DBusConnection *connection,
                                     unsigned long  *pid)
{
  dbus_bool_t result;

  _dbus_return_val_if_fail (connection != NULL, FALSE);
  _dbus_return_val_if_fail (pid != NULL, FALSE);
  
  CONNECTION_LOCK (connection);

  if (!_dbus_transport_get_is_authenticated (connection->transport))
    result = FALSE;
  else
    result = _dbus_transport_get_unix_process_id (connection->transport,
                                                  pid);
  CONNECTION_UNLOCK (connection);

  return result;
}

void
dbus_connection_set_unix_user_function (DBusConnection             *connection,
                                        DBusAllowUnixUserFunction   function,
                                        void                       *data,
                                        DBusFreeFunction            free_data_function)
{
  void *old_data = NULL;
  DBusFreeFunction old_free_function = NULL;

  _dbus_return_if_fail (connection != NULL);
  
  CONNECTION_LOCK (connection);
  _dbus_transport_set_unix_user_function (connection->transport,
                                          function, data, free_data_function,
                                          &old_data, &old_free_function);
  CONNECTION_UNLOCK (connection);

  if (old_free_function != NULL)
    (* old_free_function) (old_data);    
}

dbus_bool_t
dbus_connection_add_filter (DBusConnection            *connection,
                            DBusHandleMessageFunction  function,
                            void                      *user_data,
                            DBusFreeFunction           free_data_function)
{
  DBusMessageFilter *filter;
  
  _dbus_return_val_if_fail (connection != NULL, FALSE);
  _dbus_return_val_if_fail (function != NULL, FALSE);

  filter = dbus_new0 (DBusMessageFilter, 1);
  if (filter == NULL)
    return FALSE;

  filter->refcount.value = 1;
  
  CONNECTION_LOCK (connection);

  if (!_dbus_list_append (&connection->filter_list,
                          filter))
    {
      _dbus_message_filter_unref (filter);
      CONNECTION_UNLOCK (connection);
      return FALSE;
    }

  /* Fill in filter after all memory allocated,
   * so we don't run the free_user_data_function
   * if the add_filter() fails
   */
  
  filter->function = function;
  filter->user_data = user_data;
  filter->free_user_data_function = free_data_function;
        
  CONNECTION_UNLOCK (connection);
  return TRUE;
}

void
dbus_connection_remove_filter (DBusConnection            *connection,
                               DBusHandleMessageFunction  function,
                               void                      *user_data)
{
  DBusList *link;
  DBusMessageFilter *filter;
  
  _dbus_return_if_fail (connection != NULL);
  _dbus_return_if_fail (function != NULL);
  
  CONNECTION_LOCK (connection);

  filter = NULL;
  
  link = _dbus_list_get_last_link (&connection->filter_list);
  while (link != NULL)
    {
      filter = link->data;

      if (filter->function == function &&
          filter->user_data == user_data)
        {
          _dbus_list_remove_link (&connection->filter_list, link);
          filter->function = NULL;
          
          break;
        }
        
      link = _dbus_list_get_prev_link (&connection->filter_list, link);
    }
  
  CONNECTION_UNLOCK (connection);

#ifndef DBUS_DISABLE_CHECKS
  if (filter == NULL)
    {
      _dbus_warn ("Attempt to remove filter function %p user data %p, but no such filter has been added\n",
                  function, user_data);
      return;
    }
#endif
  
  /* Call application code */
  if (filter->free_user_data_function)
    (* filter->free_user_data_function) (filter->user_data);

  filter->free_user_data_function = NULL;
  filter->user_data = NULL;
  
  _dbus_message_filter_unref (filter);
}

dbus_bool_t
dbus_connection_register_object_path (DBusConnection              *connection,
                                      const char                  *path,
                                      const DBusObjectPathVTable  *vtable,
                                      void                        *user_data)
{
  char **decomposed_path;
  dbus_bool_t retval;
  
  _dbus_return_val_if_fail (connection != NULL, FALSE);
  _dbus_return_val_if_fail (path != NULL, FALSE);
  _dbus_return_val_if_fail (path[0] == '/', FALSE);
  _dbus_return_val_if_fail (vtable != NULL, FALSE);

  if (!_dbus_decompose_path (path, strlen (path), &decomposed_path, NULL))
    return FALSE;

  CONNECTION_LOCK (connection);

  retval = _dbus_object_tree_register (connection->objects,
                                       FALSE,
                                       (const char **) decomposed_path, vtable,
                                       user_data);

  CONNECTION_UNLOCK (connection);

  dbus_free_string_array (decomposed_path);

  return retval;
}

dbus_bool_t
dbus_connection_register_fallback (DBusConnection              *connection,
                                   const char                  *path,
                                   const DBusObjectPathVTable  *vtable,
                                   void                        *user_data)
{
  char **decomposed_path;
  dbus_bool_t retval;
  
  _dbus_return_val_if_fail (connection != NULL, FALSE);
  _dbus_return_val_if_fail (path != NULL, FALSE);
  _dbus_return_val_if_fail (path[0] == '/', FALSE);
  _dbus_return_val_if_fail (vtable != NULL, FALSE);

  if (!_dbus_decompose_path (path, strlen (path), &decomposed_path, NULL))
    return FALSE;

  CONNECTION_LOCK (connection);

  retval = _dbus_object_tree_register (connection->objects,
                                       TRUE,
                                       (const char **) decomposed_path, vtable,
                                       user_data);

  CONNECTION_UNLOCK (connection);

  dbus_free_string_array (decomposed_path);

  return retval;
}

dbus_bool_t
dbus_connection_unregister_object_path (DBusConnection              *connection,
                                        const char                  *path)
{
  char **decomposed_path;

  _dbus_return_val_if_fail (connection != NULL, FALSE);
  _dbus_return_val_if_fail (path != NULL, FALSE);
  _dbus_return_val_if_fail (path[0] == '/', FALSE);

  if (!_dbus_decompose_path (path, strlen (path), &decomposed_path, NULL))
      return FALSE;

  CONNECTION_LOCK (connection);

  _dbus_object_tree_unregister_and_unlock (connection->objects, (const char **) decomposed_path);

  dbus_free_string_array (decomposed_path);

  return TRUE;
}

dbus_bool_t
dbus_connection_get_object_path_data (DBusConnection *connection,
                                      const char     *path,
                                      void          **data_p)
{
  char **decomposed_path;

  _dbus_return_val_if_fail (connection != NULL, FALSE);
  _dbus_return_val_if_fail (path != NULL, FALSE);
  _dbus_return_val_if_fail (data_p != NULL, FALSE);

  *data_p = NULL;
  
  if (!_dbus_decompose_path (path, strlen (path), &decomposed_path, NULL))
    return FALSE;
  
  CONNECTION_LOCK (connection);

  *data_p = _dbus_object_tree_get_user_data_unlocked (connection->objects, (const char**) decomposed_path);

  CONNECTION_UNLOCK (connection);

  dbus_free_string_array (decomposed_path);

  return TRUE;
}

dbus_bool_t
dbus_connection_list_registered (DBusConnection              *connection,
                                 const char                  *parent_path,
                                 char                      ***child_entries)
{
  char **decomposed_path;
  dbus_bool_t retval;
  _dbus_return_val_if_fail (connection != NULL, FALSE);
  _dbus_return_val_if_fail (parent_path != NULL, FALSE);
  _dbus_return_val_if_fail (parent_path[0] == '/', FALSE);
  _dbus_return_val_if_fail (child_entries != NULL, FALSE);

  if (!_dbus_decompose_path (parent_path, strlen (parent_path), &decomposed_path, NULL))
    return FALSE;

  CONNECTION_LOCK (connection);

  retval = _dbus_object_tree_list_registered_and_unlock (connection->objects,
                                                         (const char **) decomposed_path,
                                                         child_entries);
  dbus_free_string_array (decomposed_path);

  return retval;
}

static DBusDataSlotAllocator slot_allocator;
_DBUS_DEFINE_GLOBAL_LOCK (connection_slots);

dbus_bool_t
dbus_connection_allocate_data_slot (dbus_int32_t *slot_p)
{
  return _dbus_data_slot_allocator_alloc (&slot_allocator,
                                          _DBUS_LOCK_NAME (connection_slots),
                                          slot_p);
}

void
dbus_connection_free_data_slot (dbus_int32_t *slot_p)
{
  _dbus_return_if_fail (*slot_p >= 0);
  
  _dbus_data_slot_allocator_free (&slot_allocator, slot_p);
}

dbus_bool_t
dbus_connection_set_data (DBusConnection   *connection,
                          dbus_int32_t      slot,
                          void             *data,
                          DBusFreeFunction  free_data_func)
{
  DBusFreeFunction old_free_func;
  void *old_data;
  dbus_bool_t retval;

  _dbus_return_val_if_fail (connection != NULL, FALSE);
  _dbus_return_val_if_fail (slot >= 0, FALSE);
  
  CONNECTION_LOCK (connection);

  retval = _dbus_data_slot_list_set (&slot_allocator,
                                     &connection->slot_list,
                                     slot, data, free_data_func,
                                     &old_free_func, &old_data);
  
  CONNECTION_UNLOCK (connection);

  if (retval)
    {
      /* Do the actual free outside the connection lock */
      if (old_free_func)
        (* old_free_func) (old_data);
    }

  return retval;
}

void*
dbus_connection_get_data (DBusConnection   *connection,
                          dbus_int32_t      slot)
{
  void *res;

  _dbus_return_val_if_fail (connection != NULL, NULL);
  
  CONNECTION_LOCK (connection);

  res = _dbus_data_slot_list_get (&slot_allocator,
                                  &connection->slot_list,
                                  slot);
  
  CONNECTION_UNLOCK (connection);

  return res;
}

void
dbus_connection_set_change_sigpipe (dbus_bool_t will_modify_sigpipe)
{  
  _dbus_modify_sigpipe = will_modify_sigpipe != FALSE;
}

void
dbus_connection_set_max_message_size (DBusConnection *connection,
                                      long            size)
{
  _dbus_return_if_fail (connection != NULL);
  
  CONNECTION_LOCK (connection);
  _dbus_transport_set_max_message_size (connection->transport,
                                        size);
  CONNECTION_UNLOCK (connection);
}

long
dbus_connection_get_max_message_size (DBusConnection *connection)
{
  long res;

  _dbus_return_val_if_fail (connection != NULL, 0);
  
  CONNECTION_LOCK (connection);
  res = _dbus_transport_get_max_message_size (connection->transport);
  CONNECTION_UNLOCK (connection);
  return res;
}

void
dbus_connection_set_max_received_size (DBusConnection *connection,
                                       long            size)
{
  _dbus_return_if_fail (connection != NULL);
  
  CONNECTION_LOCK (connection);
  _dbus_transport_set_max_received_size (connection->transport,
                                         size);
  CONNECTION_UNLOCK (connection);
}

long
dbus_connection_get_max_received_size (DBusConnection *connection)
{
  long res;

  _dbus_return_val_if_fail (connection != NULL, 0);
  
  CONNECTION_LOCK (connection);
  res = _dbus_transport_get_max_received_size (connection->transport);
  CONNECTION_UNLOCK (connection);
  return res;
}

long
dbus_connection_get_outgoing_size (DBusConnection *connection)
{
  long res;

  _dbus_return_val_if_fail (connection != NULL, 0);
  
  CONNECTION_LOCK (connection);
  res = _dbus_counter_get_value (connection->outgoing_counter);
  CONNECTION_UNLOCK (connection);
  return res;
}

---