C++ dbus_new0函数代码示例

DBusSocketSet *
_dbus_socket_set_poll_new (int size_hint)
{
  DBusSocketSetPoll *ret;

  if (size_hint <= 0)
    size_hint = DEFAULT_SIZE_HINT;

  ret = dbus_new0 (DBusSocketSetPoll, 1);

  if (ret == NULL)
    return NULL;

  ret->parent.cls = &_dbus_socket_set_poll_class;
  ret->n_fds = 0;
  ret->n_allocated = size_hint;

  ret->fds = dbus_new0 (DBusPollFD, size_hint);

  if (ret->fds == NULL)
    {
      /* socket_set_poll_free specifically supports half-constructed
       * socket sets */
      socket_set_poll_free ((DBusSocketSet *) ret);
      return NULL;
    }

  _dbus_verbose ("new socket set at %p\n", ret);
  return (DBusSocketSet *) ret;
}

dbus_bool_t
_dbus_loop_iterate (DBusLoop     *loop,
                    dbus_bool_t   block)
{
#define N_STACK_DESCRIPTORS 64
    dbus_bool_t retval;
    DBusPollFD *fds;
    DBusPollFD stack_fds[N_STACK_DESCRIPTORS];
    int n_fds;
    WatchCallback **watches_for_fds;
    WatchCallback *stack_watches_for_fds[N_STACK_DESCRIPTORS];
    int i;
    DBusList *link;
    int n_ready;
    int initial_serial;
    long timeout;
    dbus_bool_t oom_watch_pending;
    int orig_depth;

    retval = FALSE;

    fds = NULL;
    watches_for_fds = NULL;
    n_fds = 0;
    oom_watch_pending = FALSE;
    orig_depth = loop->depth;

#if MAINLOOP_SPEW
    _dbus_verbose ("Iteration block=%d depth=%d timeout_count=%d watch_count=%d\n",
                   block, loop->depth, loop->timeout_count, loop->watch_count);
#endif

    if (loop->callbacks == NULL)
        goto next_iteration;

    if (loop->watch_count > N_STACK_DESCRIPTORS)
    {
        fds = dbus_new0 (DBusPollFD, loop->watch_count);

        while (fds == NULL)
        {
            _dbus_wait_for_memory ();
            fds = dbus_new0 (DBusPollFD, loop->watch_count);
        }

        watches_for_fds = dbus_new (WatchCallback*, loop->watch_count);
        while (watches_for_fds == NULL)
        {
            _dbus_wait_for_memory ();
            watches_for_fds = dbus_new (WatchCallback*, loop->watch_count);
        }
    }

static DBusBabysitter*
_dbus_babysitter_new (void)
{
  DBusBabysitter *sitter;

  sitter = dbus_new0 (DBusBabysitter, 1);
  if (sitter == NULL)
    return NULL;

  sitter->refcount = 1;

  sitter->socket_to_babysitter.fd = -1;
  sitter->error_pipe_from_child = -1;
  
  sitter->sitter_pid = -1;
  sitter->grandchild_pid = -1;

  sitter->watches = _dbus_watch_list_new ();
  if (sitter->watches == NULL)
    goto failed;
  
  return sitter;

 failed:
  _dbus_babysitter_unref (sitter);
  return NULL;
}

static DBusKeyring*
_dbus_keyring_new (void)
{
  DBusKeyring *keyring;

  keyring = dbus_new0 (DBusKeyring, 1);
  if (keyring == NULL)
    goto out_0;
  
  if (!_dbus_string_init (&keyring->directory))
    goto out_1;

  if (!_dbus_string_init (&keyring->filename))
    goto out_2;

  if (!_dbus_string_init (&keyring->filename_lock))
    goto out_3;
  
  keyring->refcount = 1;
  keyring->keys = NULL;
  keyring->n_keys = 0;

  return keyring;

 out_3:
  _dbus_string_free (&keyring->filename);
 out_2:
  _dbus_string_free (&keyring->directory);
 out_1:
  dbus_free (keyring);
 out_0:
  return NULL;
}

/**
 * Creates a new DBusWatch. Used to add a file descriptor to be polled
 * by a main loop.
 * 
 * @param fd the file descriptor to be watched.
 * @param flags the conditions to watch for on the descriptor.
 * @param enabled the initial enabled state
 * @param handler the handler function
 * @param data data for handler function
 * @param free_data_function function to free the data
 * @returns the new DBusWatch object.
 */
DBusWatch*
_dbus_watch_new (int               fd,
                 unsigned int      flags,
                 dbus_bool_t       enabled,
                 DBusWatchHandler  handler,
                 void             *data,
                 DBusFreeFunction  free_data_function)
{
  DBusWatch *watch;

#define VALID_WATCH_FLAGS (DBUS_WATCH_WRITABLE | DBUS_WATCH_READABLE)
  
  _dbus_assert ((flags & VALID_WATCH_FLAGS) == flags);
  
  watch = dbus_new0 (DBusWatch, 1);
  if (watch == NULL)
    return NULL;
  
  watch->refcount = 1;
  watch->fd = fd;
  watch->flags = flags;
  watch->enabled = enabled;

  watch->handler = handler;
  watch->handler_data = data;
  watch->free_handler_data_function = free_data_function;
  
  return watch;
}

DBusLoop*
_dbus_loop_new (void)
{
  DBusLoop *loop;

  loop = dbus_new0 (DBusLoop, 1);
  if (loop == NULL)
    return NULL;

  loop->watches = _dbus_hash_table_new (DBUS_HASH_POLLABLE, NULL,
                                        free_watch_table_entry);

  loop->socket_set = _dbus_socket_set_new (0);

  if (loop->watches == NULL || loop->socket_set == NULL)
    {
      if (loop->watches != NULL)
        _dbus_hash_table_unref (loop->watches);

      if (loop->socket_set != NULL)
        _dbus_socket_set_free (loop->socket_set);

      dbus_free (loop);
      return NULL;
    }

  loop->refcount = 1;

  return loop;
}

DBusDirIter*
_dbus_directory_open (const DBusString *filename,
                      DBusError        *error)
{
  DIR *d;
  DBusDirIter *iter;
  const char *filename_c;

  _DBUS_ASSERT_ERROR_IS_CLEAR (error);
  
  filename_c = _dbus_string_get_const_data (filename);

  d = opendir (filename_c);
  if (d == NULL)
    {
      dbus_set_error (error, _dbus_error_from_errno (errno),
                      "Failed to read directory \"%s\": %s",
                      filename_c,
                      _dbus_strerror (errno));
      return NULL;
    }
  iter = dbus_new0 (DBusDirIter, 1);
  if (iter == NULL)
    {
      closedir (d);
      dbus_set_error (error, DBUS_ERROR_NO_MEMORY,
                      "Could not allocate memory for directory iterator");
      return NULL;
    }

  iter->d = d;

  return iter;
}

static DBusMutex *
dbus_fake_mutex_new (void)
{
  DBusFakeMutex *mutex;

  mutex = dbus_new0 (DBusFakeMutex, 1);

  return (DBusMutex *)mutex;
}

/**
 * Creates a new pending reply object.
 *
 * @param connection connection where reply will arrive
 * @param timeout_milliseconds length of timeout, -1 (or
 *  #DBUS_TIMEOUT_USE_DEFAULT) for default,
 *  #DBUS_TIMEOUT_INFINITE for no timeout
 * @param timeout_handler timeout handler, takes pending call as data
 * @returns a new #DBusPendingCall or #NULL if no memory.
 */
DBusPendingCall*
_dbus_pending_call_new_unlocked (DBusConnection    *connection,
                                 int                timeout_milliseconds,
                                 DBusTimeoutHandler timeout_handler)
{
  DBusPendingCall *pending;
  DBusTimeout *timeout;

  _dbus_assert (timeout_milliseconds >= 0 || timeout_milliseconds == -1);
 
  if (timeout_milliseconds == -1)
    timeout_milliseconds = _DBUS_DEFAULT_TIMEOUT_VALUE;

  if (!dbus_pending_call_allocate_data_slot (&notify_user_data_slot))
    return NULL;
  
  pending = dbus_new0 (DBusPendingCall, 1);
  
  if (pending == NULL)
    {
      dbus_pending_call_free_data_slot (&notify_user_data_slot);
      return NULL;
    }

  if (timeout_milliseconds != DBUS_TIMEOUT_INFINITE)
    {
      timeout = _dbus_timeout_new (timeout_milliseconds,
                                   timeout_handler,
                                   pending, NULL);  

      if (timeout == NULL)
        {
          dbus_pending_call_free_data_slot (&notify_user_data_slot);
          dbus_free (pending);
          return NULL;
        }

      pending->timeout = timeout;
    }
  else
    {
      pending->timeout = NULL;
    }

  _dbus_atomic_inc (&pending->refcount);
  pending->connection = connection;
  _dbus_connection_ref_unlocked (pending->connection);

  _dbus_data_slot_list_init (&pending->slot_list);

  _dbus_pending_call_trace_ref (pending, 0, 1, "new_unlocked");

  return pending;
}

/**
 * Creates a new timeout list. Returns #NULL if insufficient
 * memory exists.
 *
 * @returns the new timeout list, or #NULL on failure.
 */
DBusTimeoutList*
_dbus_timeout_list_new (void)
{
  DBusTimeoutList *timeout_list;

  timeout_list = dbus_new0 (DBusTimeoutList, 1);
  if (timeout_list == NULL)
    return NULL;

  return timeout_list;
}

/**
 * Creates a new pending reply object.
 *
 * @param connection connection where reply will arrive
 * @param timeout_milliseconds length of timeout, -1 for default
 * @param timeout_handler timeout handler, takes pending call as data
 * @returns a new #DBusPendingCall or #NULL if no memory.
 */
DBusPendingCall*
_dbus_pending_call_new_unlocked (DBusConnection    *connection,
                                 int                timeout_milliseconds,
                                 DBusTimeoutHandler timeout_handler)
{
  DBusPendingCall *pending;
  DBusTimeout *timeout;

  _dbus_assert (timeout_milliseconds >= 0 || timeout_milliseconds == -1);
 
  if (timeout_milliseconds == -1)
    timeout_milliseconds = _DBUS_DEFAULT_TIMEOUT_VALUE;

  /* it would probably seem logical to pass in _DBUS_INT_MAX for
   * infinite timeout, but then math in
   * _dbus_connection_block_for_reply would get all overflow-prone, so
   * smack that down.
   */
  if (timeout_milliseconds > _DBUS_ONE_HOUR_IN_MILLISECONDS * 6)
    timeout_milliseconds = _DBUS_ONE_HOUR_IN_MILLISECONDS * 6;
  
  if (!dbus_pending_call_allocate_data_slot (&notify_user_data_slot))
    return NULL;
  
  pending = dbus_new0 (DBusPendingCall, 1);
  
  if (pending == NULL)
    {
      dbus_pending_call_free_data_slot (&notify_user_data_slot);
      return NULL;
    }

  timeout = _dbus_timeout_new (timeout_milliseconds,
                               timeout_handler,
			       pending, NULL);  

  if (timeout == NULL)
    {
      dbus_pending_call_free_data_slot (&notify_user_data_slot);
      dbus_free (pending);
      return NULL;
    }
  
  pending->refcount.value = 1;
  pending->connection = connection;
  _dbus_connection_ref_unlocked (pending->connection);

  pending->timeout = timeout;


  _dbus_data_slot_list_init (&pending->slot_list);
  
  return pending;
}

/**
 * Creates a new watch list. Returns #NULL if insufficient
 * memory exists.
 *
 * @returns the new watch list, or #NULL on failure.
 */
DBusWatchList*
_dbus_watch_list_new (void)
{
  DBusWatchList *watch_list;

  watch_list = dbus_new0 (DBusWatchList, 1);
  if (watch_list == NULL)
    return NULL;

  return watch_list;
}

static dbus_bool_t
setup_server (BusContext *context,
              DBusServer *server,
              char      **auth_mechanisms,
              DBusError  *error)
{
  BusServerData *bd;

  bd = dbus_new0 (BusServerData, 1);
  if (bd == NULL || !dbus_server_set_data (server,
                                           server_data_slot,
                                           bd, free_server_data))
    {
      dbus_free (bd);
      BUS_SET_OOM (error);
      return FALSE;
    }

  bd->context = context;

  if (!dbus_server_set_auth_mechanisms (server, (const char**) auth_mechanisms))
    {
      BUS_SET_OOM (error);
      return FALSE;
    }

  dbus_server_set_new_connection_function (server,
                                           new_connection_callback,
                                           context, NULL);

  if (!dbus_server_set_watch_functions (server,
                                        add_server_watch,
                                        remove_server_watch,
                                        toggle_server_watch,
                                        server,
                                        NULL))
    {
      BUS_SET_OOM (error);
      return FALSE;
    }

  if (!dbus_server_set_timeout_functions (server,
                                          add_server_timeout,
                                          remove_server_timeout,
                                          NULL,
                                          server, NULL))
    {
      BUS_SET_OOM (error);
      return FALSE;
    }

  return TRUE;
}

/**
 * Creates a new DBusCounter. DBusCounter is used
 * to count usage of some resource such as memory.
 *
 * @returns new counter or #NULL on failure
 */
DBusCounter*
_dbus_counter_new (void)
{
  DBusCounter *counter;

  counter = dbus_new0 (DBusCounter, 1);
  if (counter == NULL)
    return NULL;

  counter->refcount = 1;

  return counter;
}

DBusLoop*
_dbus_loop_new (void)
{
    DBusLoop *loop;

    loop = dbus_new0 (DBusLoop, 1);
    if (loop == NULL)
        return NULL;

    loop->refcount = 1;

    return loop;
}