D-Bus 1.15.8
dbus-watch.c
1/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
2/* dbus-watch.c DBusWatch implementation
3 *
4 * Copyright (C) 2002, 2003 Red Hat Inc.
5 *
6 * SPDX-License-Identifier: AFL-2.1 OR GPL-2.0-or-later
7 *
8 * Licensed under the Academic Free License version 2.1
9 *
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 *
24 */
25
26#include <config.h>
27#include "dbus-internals.h"
28#include "dbus-watch.h"
29#include "dbus-list.h"
30
43{
45 DBusPollable fd;
46 unsigned int flags;
52 void *data;
54 unsigned int enabled : 1;
55 unsigned int oom_last_time : 1;
56};
57
59_dbus_watch_get_enabled (DBusWatch *watch)
60{
61 return watch->enabled;
62}
63
65_dbus_watch_get_oom_last_time (DBusWatch *watch)
66{
67 return watch->oom_last_time;
68}
69
70void
71_dbus_watch_set_oom_last_time (DBusWatch *watch,
72 dbus_bool_t oom)
73{
74 watch->oom_last_time = oom;
75}
76
90_dbus_watch_new (DBusPollable fd,
91 unsigned int flags,
92 dbus_bool_t enabled,
93 DBusWatchHandler handler,
94 void *data,
95 DBusFreeFunction free_data_function)
96{
97 DBusWatch *watch;
98
99#define VALID_WATCH_FLAGS (DBUS_WATCH_WRITABLE | DBUS_WATCH_READABLE)
100
101 _dbus_assert ((flags & VALID_WATCH_FLAGS) == flags);
102
103 watch = dbus_new0 (DBusWatch, 1);
104 if (watch == NULL)
105 return NULL;
106
107 watch->refcount = 1;
108 watch->fd = fd;
109 watch->flags = flags;
110 watch->enabled = enabled;
111
112 watch->handler = handler;
113 watch->handler_data = data;
114 watch->free_handler_data_function = free_data_function;
115
116 return watch;
117}
118
125DBusWatch *
127{
128 watch->refcount += 1;
129
130 return watch;
131}
132
139void
141{
142 _dbus_assert (watch != NULL);
143 _dbus_assert (watch->refcount > 0);
144
145 watch->refcount -= 1;
146 if (watch->refcount == 0)
147 {
148 if (_dbus_pollable_is_valid (watch->fd))
149 _dbus_warn ("this watch should have been invalidated");
150
151 dbus_watch_set_data (watch, NULL, NULL); /* call free_data_function */
152
154 (* watch->free_handler_data_function) (watch->handler_data);
155
156 dbus_free (watch);
157 }
158}
159
170void
172{
173 _dbus_pollable_invalidate (&watch->fd);
174 watch->flags = 0;
175}
176
186void
188 unsigned int *condition)
189{
190 if (!(watch->flags & DBUS_WATCH_READABLE))
191 *condition &= ~DBUS_WATCH_READABLE;
192 if (!(watch->flags & DBUS_WATCH_WRITABLE))
193 *condition &= ~DBUS_WATCH_WRITABLE;
194}
195
196
217{
225};
226
235{
236 DBusWatchList *watch_list;
237
238 watch_list = dbus_new0 (DBusWatchList, 1);
239 if (watch_list == NULL)
240 return NULL;
241
242 return watch_list;
243}
244
250void
252{
253 /* free watch_data and removes watches as a side effect */
255 NULL, NULL, NULL, NULL, NULL);
256
257 _dbus_list_clear_full (&watch_list->watches,
259
260 dbus_free (watch_list);
261}
262
263#ifdef DBUS_ENABLE_VERBOSE_MODE
264static const char*
265watch_flags_to_string (int flags)
266{
267 const char *watch_type;
268
269 if ((flags & DBUS_WATCH_READABLE) &&
270 (flags & DBUS_WATCH_WRITABLE))
271 watch_type = "readwrite";
272 else if (flags & DBUS_WATCH_READABLE)
273 watch_type = "read";
274 else if (flags & DBUS_WATCH_WRITABLE)
275 watch_type = "write";
276 else
277 watch_type = "not read or write";
278 return watch_type;
279}
280#endif /* DBUS_ENABLE_VERBOSE_MODE */
281
298 DBusAddWatchFunction add_function,
299 DBusRemoveWatchFunction remove_function,
300 DBusWatchToggledFunction toggled_function,
301 void *data,
302 DBusFreeFunction free_data_function)
303{
304 /* Add watches with the new watch function, failing on OOM */
305 if (add_function != NULL)
306 {
307 DBusList *link;
308
309 link = _dbus_list_get_first_link (&watch_list->watches);
310 while (link != NULL)
311 {
312 DBusList *next = _dbus_list_get_next_link (&watch_list->watches,
313 link);
314#ifdef DBUS_ENABLE_VERBOSE_MODE
315 DBusWatch *watch = link->data;
316
317 _dbus_verbose ("Adding a %s watch on fd %" DBUS_POLLABLE_FORMAT " using newly-set add watch function\n",
318 watch_flags_to_string (dbus_watch_get_flags (link->data)),
319 _dbus_pollable_printable (watch->fd));
320#endif
321
322 if (!(* add_function) (link->data, data))
323 {
324 /* remove it all again and return FALSE */
325 DBusList *link2;
326
327 link2 = _dbus_list_get_first_link (&watch_list->watches);
328 while (link2 != link)
329 {
330 DBusList *next2 = _dbus_list_get_next_link (&watch_list->watches,
331 link2);
332#ifdef DBUS_ENABLE_VERBOSE_MODE
333 DBusWatch *watch2 = link2->data;
334
335 _dbus_verbose ("Removing watch on fd %" DBUS_POLLABLE_FORMAT " using newly-set remove function because initial add failed\n",
336 _dbus_pollable_printable (watch2->fd));
337#endif
338
339 (* remove_function) (link2->data, data);
340
341 link2 = next2;
342 }
343
344 return FALSE;
345 }
346
347 link = next;
348 }
349 }
350
351 /* Remove all current watches from previous watch handlers */
352
353 if (watch_list->remove_watch_function != NULL)
354 {
355 _dbus_verbose ("Removing all pre-existing watches\n");
356
357 _dbus_list_foreach (&watch_list->watches,
359 watch_list->watch_data);
360 }
361
362 if (watch_list->watch_free_data_function != NULL)
363 (* watch_list->watch_free_data_function) (watch_list->watch_data);
364
365 watch_list->add_watch_function = add_function;
366 watch_list->remove_watch_function = remove_function;
367 watch_list->watch_toggled_function = toggled_function;
368 watch_list->watch_data = data;
369 watch_list->watch_free_data_function = free_data_function;
370
371 return TRUE;
372}
373
384 DBusWatch *watch)
385{
386 if (!_dbus_list_append (&watch_list->watches, watch))
387 return FALSE;
388
389 _dbus_watch_ref (watch);
390
391 if (watch_list->add_watch_function != NULL)
392 {
393 _dbus_verbose ("Adding watch on fd %" DBUS_POLLABLE_FORMAT "\n",
394 _dbus_pollable_printable (watch->fd));
395
396 if (!(* watch_list->add_watch_function) (watch,
397 watch_list->watch_data))
398 {
399 _dbus_list_remove_last (&watch_list->watches, watch);
400 _dbus_watch_unref (watch);
401 return FALSE;
402 }
403 }
404
405 return TRUE;
406}
407
415void
417 DBusWatch *watch)
418{
419 if (!_dbus_list_remove (&watch_list->watches, watch))
420 _dbus_assert_not_reached ("Nonexistent watch was removed");
421
422 if (watch_list->remove_watch_function != NULL)
423 {
424 _dbus_verbose ("Removing watch on fd %" DBUS_POLLABLE_FORMAT "\n",
425 _dbus_pollable_printable (watch->fd));
426
427 (* watch_list->remove_watch_function) (watch,
428 watch_list->watch_data);
429 }
430
431 _dbus_watch_unref (watch);
432}
433
442void
444 DBusWatch *watch,
445 dbus_bool_t enabled)
446{
447 enabled = !!enabled;
448
449 if (enabled == watch->enabled)
450 return;
451
452 watch->enabled = enabled;
453
454 if (watch_list->watch_toggled_function != NULL)
455 {
456 _dbus_verbose ("Toggling watch %p on fd %" DBUS_POLLABLE_FORMAT " to %d\n",
457 watch,
458 _dbus_pollable_printable (watch->fd),
459 watch->enabled);
460
461 (* watch_list->watch_toggled_function) (watch,
462 watch_list->watch_data);
463 }
464}
465
473void
475 dbus_bool_t enabled)
476{
477 DBusList *link;
478
479 for (link = _dbus_list_get_first_link (&watch_list->watches);
480 link != NULL;
481 link = _dbus_list_get_next_link (&watch_list->watches, link))
482 {
483 _dbus_watch_list_toggle_watch (watch_list, link->data, enabled);
484 }
485}
486
499void
501 DBusWatchHandler handler,
502 void *data,
503 DBusFreeFunction free_data_function)
504{
506 (* watch->free_handler_data_function) (watch->handler_data);
507
508 watch->handler = handler;
509 watch->handler_data = data;
510 watch->free_handler_data_function = free_data_function;
511}
512
544int
546{
547 _dbus_return_val_if_fail (watch != NULL, -1);
548
549 return dbus_watch_get_unix_fd(watch);
550}
551
565int
567{
568 _dbus_return_val_if_fail (watch != NULL, -1);
569
570 /* FIXME remove #ifdef and do this on a lower level
571 * (watch should have set_socket and set_unix_fd and track
572 * which it has, and the transport should provide the
573 * appropriate watch type)
574 */
575#ifdef DBUS_UNIX
576 return watch->fd;
577#else
578 return dbus_watch_get_socket( watch );
579#endif
580}
581
594int
596{
597 _dbus_return_val_if_fail (watch != NULL, -1);
598
599#ifdef DBUS_UNIX
600 return watch->fd;
601#else
602 return _dbus_socket_get_int (watch->fd);
603#endif
604}
605
607_dbus_watch_get_socket (DBusWatch *watch)
608{
609 DBusSocket s;
610
611 _dbus_assert (watch != NULL);
612
613#ifdef DBUS_UNIX
614 s.fd = watch->fd;
615#else
616 s = watch->fd;
617#endif
618
619 return s;
620}
621
622DBusPollable
623_dbus_watch_get_pollable (DBusWatch *watch)
624{
625 _dbus_assert (watch != NULL);
626
627 return watch->fd;
628}
629
643unsigned int
645{
646 _dbus_return_val_if_fail (watch != NULL, 0);
647 _dbus_assert ((watch->flags & VALID_WATCH_FLAGS) == watch->flags);
648
649 return watch->flags;
650}
651
659void*
661{
662 _dbus_return_val_if_fail (watch != NULL, NULL);
663
664 return watch->data;
665}
666
678void
680 void *data,
681 DBusFreeFunction free_data_function)
682{
683 _dbus_return_if_fail (watch != NULL);
684
685 _dbus_verbose ("Setting watch fd %" DBUS_POLLABLE_FORMAT " data to data = %p function = %p from data = %p function = %p\n",
686 _dbus_pollable_printable (watch->fd),
687 data, free_data_function, watch->data, watch->free_data_function);
688
689 if (watch->free_data_function != NULL)
690 (* watch->free_data_function) (watch->data);
691
692 watch->data = data;
693 watch->free_data_function = free_data_function;
694}
695
705{
706 _dbus_return_val_if_fail (watch != NULL, FALSE);
707
708 return watch->enabled;
709}
710
711
736 unsigned int flags)
737{
738 _dbus_return_val_if_fail (watch != NULL, FALSE);
739
740#ifndef DBUS_DISABLE_CHECKS
741 if (!_dbus_pollable_is_valid (watch->fd) || watch->flags == 0)
742 {
743 _dbus_warn_check_failed ("Watch is invalid, it should have been removed");
744 return TRUE;
745 }
746#endif
747
748 _dbus_return_val_if_fail (_dbus_pollable_is_valid (watch->fd) /* fails if watch was removed */, TRUE);
749
750 _dbus_watch_sanitize_condition (watch, &flags);
751
752 if (flags == 0)
753 {
754 _dbus_verbose ("After sanitization, watch flags on fd %" DBUS_POLLABLE_FORMAT " were 0\n",
755 _dbus_pollable_printable (watch->fd));
756 return TRUE;
757 }
758 else
759 return (* watch->handler) (watch, flags,
760 watch->handler_data);
761}
762
763
void(* DBusWatchToggledFunction)(DBusWatch *watch, void *data)
Called when dbus_watch_get_enabled() may return a different value than it did before.
dbus_bool_t(* DBusAddWatchFunction)(DBusWatch *watch, void *data)
Called when libdbus needs a new watch to be monitored by the main loop.
void(* DBusRemoveWatchFunction)(DBusWatch *watch, void *data)
Called when libdbus no longer needs a watch to be monitored by the main loop.
@ DBUS_WATCH_READABLE
As in POLLIN.
@ DBUS_WATCH_WRITABLE
As in POLLOUT.
#define _dbus_assert_not_reached(explanation)
Aborts with an error message if called.
#define _dbus_assert(condition)
Aborts with an error message if the condition is false.
void _dbus_warn_check_failed(const char *format,...)
Prints a "critical" warning to stderr when an assertion fails; differs from _dbus_warn primarily in t...
void(* DBusForeachFunction)(void *element, void *data)
Used to iterate over each item in a collection, such as a DBusList.
void _dbus_warn(const char *format,...)
Prints a warning message to stderr.
DBusList * _dbus_list_get_first_link(DBusList **list)
Gets the first link in the list.
Definition: dbus-list.c:597
dbus_bool_t _dbus_list_remove(DBusList **list, void *data)
Removes a value from the list.
Definition: dbus-list.c:418
void _dbus_list_clear_full(DBusList **list, DBusFreeFunction function)
Free every link and every element in the list.
Definition: dbus-list.c:570
void _dbus_list_foreach(DBusList **list, DBusForeachFunction function, void *data)
Calls the given function for each element in the list.
Definition: dbus-list.c:789
dbus_bool_t _dbus_list_remove_last(DBusList **list, void *data)
Removes a value from the list.
Definition: dbus-list.c:449
dbus_bool_t _dbus_list_append(DBusList **list, void *data)
Appends a value to the list.
Definition: dbus-list.c:273
#define _dbus_list_get_next_link(list, link)
Gets the next link in the list, or NULL if there are no more links.
Definition: dbus-list.h:121
#define NULL
A null pointer, defined appropriately for C or C++.
#define TRUE
Expands to "1".
#define FALSE
Expands to "0".
void(* DBusFreeFunction)(void *memory)
The type of a function which frees a block of memory.
Definition: dbus-memory.h:65
void dbus_free(void *memory)
Frees a block of memory previously allocated by dbus_malloc() or dbus_malloc0().
Definition: dbus-memory.c:694
#define dbus_new0(type, count)
Safe macro for using dbus_malloc0().
Definition: dbus-memory.h:60
dbus_uint32_t dbus_bool_t
A boolean, valid values are TRUE and FALSE.
Definition: dbus-types.h:37
dbus_bool_t _dbus_watch_list_add_watch(DBusWatchList *watch_list, DBusWatch *watch)
Adds a new watch to the watch list, invoking the application DBusAddWatchFunction if appropriate.
Definition: dbus-watch.c:383
void _dbus_watch_list_toggle_watch(DBusWatchList *watch_list, DBusWatch *watch, dbus_bool_t enabled)
Sets a watch to the given enabled state, invoking the application's DBusWatchToggledFunction if appro...
Definition: dbus-watch.c:443
DBusWatchList * _dbus_watch_list_new(void)
Creates a new watch list.
Definition: dbus-watch.c:234
void _dbus_watch_list_free(DBusWatchList *watch_list)
Frees a DBusWatchList.
Definition: dbus-watch.c:251
dbus_bool_t _dbus_watch_list_set_functions(DBusWatchList *watch_list, DBusAddWatchFunction add_function, DBusRemoveWatchFunction remove_function, DBusWatchToggledFunction toggled_function, void *data, DBusFreeFunction free_data_function)
Sets the watch functions.
Definition: dbus-watch.c:297
void _dbus_watch_set_handler(DBusWatch *watch, DBusWatchHandler handler, void *data, DBusFreeFunction free_data_function)
Sets the handler for the watch.
Definition: dbus-watch.c:500
void _dbus_watch_list_toggle_all_watches(DBusWatchList *watch_list, dbus_bool_t enabled)
Sets all watches to the given enabled state, invoking the application's DBusWatchToggledFunction if a...
Definition: dbus-watch.c:474
void _dbus_watch_sanitize_condition(DBusWatch *watch, unsigned int *condition)
Sanitizes the given condition so that it only contains flags that the DBusWatch requested.
Definition: dbus-watch.c:187
DBusWatch * _dbus_watch_new(DBusPollable fd, unsigned int flags, dbus_bool_t enabled, DBusWatchHandler handler, void *data, DBusFreeFunction free_data_function)
Creates a new DBusWatch.
Definition: dbus-watch.c:90
dbus_bool_t(* DBusWatchHandler)(DBusWatch *watch, unsigned int flags, void *data)
function to run when the watch is handled
Definition: dbus-watch.h:45
DBusWatch * _dbus_watch_ref(DBusWatch *watch)
Increments the reference count of a DBusWatch object.
Definition: dbus-watch.c:126
void _dbus_watch_unref(DBusWatch *watch)
Decrements the reference count of a DBusWatch object and finalizes the object if the count reaches ze...
Definition: dbus-watch.c:140
void _dbus_watch_list_remove_watch(DBusWatchList *watch_list, DBusWatch *watch)
Removes a watch from the watch list, invoking the application's DBusRemoveWatchFunction if appropriat...
Definition: dbus-watch.c:416
void _dbus_watch_invalidate(DBusWatch *watch)
Clears the file descriptor from a now-invalid watch object so that no one tries to use it.
Definition: dbus-watch.c:171
DBUS_EXPORT int dbus_watch_get_unix_fd(DBusWatch *watch)
Returns a UNIX file descriptor to be watched, which may be a pipe, socket, or other type of descripto...
Definition: dbus-watch.c:566
DBUS_EXPORT void dbus_watch_set_data(DBusWatch *watch, void *data, DBusFreeFunction free_data_function)
Sets data which can be retrieved with dbus_watch_get_data().
Definition: dbus-watch.c:679
DBUS_EXPORT DBUS_DEPRECATED int dbus_watch_get_fd(DBusWatch *watch)
Deprecated former name of dbus_watch_get_unix_fd().
Definition: dbus-watch.c:545
DBUS_EXPORT void * dbus_watch_get_data(DBusWatch *watch)
Gets data previously set with dbus_watch_set_data() or NULL if none.
Definition: dbus-watch.c:660
DBUS_EXPORT int dbus_watch_get_socket(DBusWatch *watch)
Returns a socket to be watched, on UNIX this will return -1 if our transport is not socket-based so d...
Definition: dbus-watch.c:595
DBUS_EXPORT dbus_bool_t dbus_watch_handle(DBusWatch *watch, unsigned int flags)
Called to notify the D-Bus library when a previously-added watch is ready for reading or writing,...
Definition: dbus-watch.c:735
DBUS_EXPORT dbus_bool_t dbus_watch_get_enabled(DBusWatch *watch)
Returns whether a watch is enabled or not.
Definition: dbus-watch.c:704
DBUS_EXPORT unsigned int dbus_watch_get_flags(DBusWatch *watch)
Gets flags from DBusWatchFlags indicating what conditions should be monitored on the file descriptor.
Definition: dbus-watch.c:644
A node in a linked list.
Definition: dbus-list.h:37
void * data
Data stored at this element.
Definition: dbus-list.h:40
Socket interface.
Definition: dbus-sysdeps.h:185
DBusWatchList implementation details.
Definition: dbus-watch.c:217
DBusFreeFunction watch_free_data_function
Free function for watch callback data.
Definition: dbus-watch.c:224
DBusRemoveWatchFunction remove_watch_function
Callback for removing a watch.
Definition: dbus-watch.c:221
void * watch_data
Data for watch callbacks.
Definition: dbus-watch.c:223
DBusList * watches
Watch objects.
Definition: dbus-watch.c:218
DBusAddWatchFunction add_watch_function
Callback for adding a watch.
Definition: dbus-watch.c:220
DBusWatchToggledFunction watch_toggled_function
Callback on toggling enablement.
Definition: dbus-watch.c:222
Implementation of DBusWatch.
Definition: dbus-watch.c:43
unsigned int enabled
Whether it's enabled.
Definition: dbus-watch.c:54
unsigned int oom_last_time
Whether it was OOM last time.
Definition: dbus-watch.c:55
int refcount
Reference count.
Definition: dbus-watch.c:44
DBusFreeFunction free_handler_data_function
Free the watch handler data.
Definition: dbus-watch.c:50
void * data
Application data.
Definition: dbus-watch.c:52
DBusPollable fd
File descriptor.
Definition: dbus-watch.c:45
unsigned int flags
Conditions to watch.
Definition: dbus-watch.c:46
DBusWatchHandler handler
Watch handler.
Definition: dbus-watch.c:48
DBusFreeFunction free_data_function
Free the application data.
Definition: dbus-watch.c:53
void * handler_data
Watch handler data.
Definition: dbus-watch.c:49