D-Bus  1.12.16
dbus-sysdeps.h
1 /* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
2 /* dbus-sysdeps.h Wrappers around system/libc features (internal to D-Bus implementation)
3  *
4  * Copyright (C) 2002, 2003 Red Hat, Inc.
5  * Copyright (C) 2003 CodeFactory AB
6  *
7  * Licensed under the Academic Free License version 2.1
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22  *
23  */
24 
25 #ifndef DBUS_SYSDEPS_H
26 #define DBUS_SYSDEPS_H
27 
28 #ifndef VERSION
29 #warning Please include config.h before dbus-sysdeps.h
30 #include "config.h"
31 #endif
32 
33 #ifdef HAVE_STDINT_H
34 #include <stdint.h>
35 #endif
36 
37 #ifdef HAVE_INTTYPES_H
38 #include <inttypes.h>
39 #endif
40 
41 #include <dbus/dbus-errors.h>
42 #include <dbus/dbus-file.h>
43 #include <dbus/dbus-string.h>
44 
45 /* this is perhaps bogus, but strcmp() etc. are faster if we use the
46  * stuff straight out of string.h, so have this here for now.
47  */
48 #include <string.h>
49 #include <stdarg.h>
50 
51 #if !defined(BROKEN_POLL) && (defined(__APPLE__) || defined(__INTERIX))
52  /* Following libcurl's example, we blacklist poll() on Darwin
53  * (macOS, iOS, etc.) and Interix due to a history of implementation
54  * issues.
55  * https://github.com/curl/curl/blob/master/m4/curl-functions.m4
56  *
57  * On unspecified older macOS versions, poll() failed if given a
58  * device node to poll.
59  *
60  * On macOS < 10.9, poll() with nfds=0 failed instead of waiting for
61  * the timeout and then succeeding.
62  *
63  * On macOS >= 10.12, poll() with nfds=0 succeeded immediately
64  * instead of waiting for the timeout, resulting in busy-looping.
65  *
66  * On Interix, poll() apparently only works for files in /proc.
67  *
68  * The "legacy" build flavour in our CI machinery defines BROKEN_POLL
69  * on whatever platform is in use (normally Linux) to force use of the
70  * same select()-based poll() emulation that we use for macOS, Interix,
71  * and any platform that lacks a real poll(), so that we can test it
72  * more regularly.
73  */
74 # define BROKEN_POLL
75 #endif
76 
77 /* AIX sys/poll.h does #define events reqevents, and other
78  * wonderousness, so must include sys/poll before declaring
79  * DBusPollFD
80  */
81 #ifdef HAVE_POLL
82 #include <sys/poll.h>
83 #endif
84 
85 #ifdef DBUS_WINCE
86 /* Windows CE lacks some system functions (such as errno and clock).
87  We bring them in here. */
88 #include "dbus-sysdeps-wince-glue.h"
89 #endif
90 
91 #ifdef DBUS_WIN
92 #include <ws2tcpip.h>
93 #endif
94 
96 
97 #ifdef DBUS_WIN
98 #define _DBUS_PATH_SEPARATOR ";"
99 #else
100 #define _DBUS_PATH_SEPARATOR ":"
101 #endif
102 
103 /* Forward declarations */
104 
105 
107 typedef struct DBusList DBusList;
108 
110 typedef struct DBusCredentials DBusCredentials;
111 
113 typedef struct DBusPipe DBusPipe;
114 
121 DBUS_PRIVATE_EXPORT
122 void _dbus_abort (void) _DBUS_GNUC_NORETURN;
123 
125 DBUS_PRIVATE_EXPORT
126 const char* _dbus_getenv (const char *varname);
127 DBUS_PRIVATE_EXPORT
129 char ** _dbus_get_environment (void);
130 
132 typedef unsigned long dbus_pid_t;
134 typedef unsigned long dbus_uid_t;
136 typedef unsigned long dbus_gid_t;
137 
139 #define DBUS_PID_UNSET ((dbus_pid_t) -1)
140 
141 #define DBUS_UID_UNSET ((dbus_uid_t) -1)
142 
143 #define DBUS_GID_UNSET ((dbus_gid_t) -1)
144 
146 #define DBUS_PID_FORMAT "%lu"
147 
148 #define DBUS_UID_FORMAT "%lu"
149 
150 #define DBUS_GID_FORMAT "%lu"
151 
155 #ifdef DBUS_WIN
156 
157 typedef struct { SOCKET sock; } DBusSocket;
158 # define DBUS_SOCKET_FORMAT "Iu"
159 # define DBUS_SOCKET_INIT { INVALID_SOCKET }
160 
161 static inline SOCKET
162 _dbus_socket_printable (DBusSocket s) { return s.sock; }
163 
164 static inline dbus_bool_t
165 _dbus_socket_is_valid (DBusSocket s) { return s.sock != INVALID_SOCKET; }
166 
167 static inline void
168 _dbus_socket_invalidate (DBusSocket *s) { s->sock = INVALID_SOCKET; }
169 
170 static inline int
171 _dbus_socket_get_int (DBusSocket s) { return (int)s.sock; }
172 
173 #else /* not DBUS_WIN */
174 
175 typedef struct { int fd; } DBusSocket;
176 # define DBUS_SOCKET_FORMAT "d"
177 # define DBUS_SOCKET_INIT { -1 }
178 
179 static inline int
180 _dbus_socket_printable (DBusSocket s) { return s.fd; }
181 
182 static inline dbus_bool_t
183 _dbus_socket_is_valid (DBusSocket s) { return s.fd >= 0; }
184 
185 static inline void
186 _dbus_socket_invalidate (DBusSocket *s) { s->fd = -1; }
187 
188 static inline int
189 _dbus_socket_get_int (DBusSocket s) { return s.fd; }
190 
191 #endif /* not DBUS_WIN */
192 
193 static inline DBusSocket
194 _dbus_socket_get_invalid (void)
195 {
196  DBusSocket s = DBUS_SOCKET_INIT;
197 
198  return s;
199 }
200 
202  DBusError *error);
203 
204 DBUS_PRIVATE_EXPORT
206  DBusError *error);
207 DBUS_PRIVATE_EXPORT
209  DBusString *buffer,
210  int count);
211 DBUS_PRIVATE_EXPORT
213  const DBusString *buffer,
214  int start,
215  int len);
217  const DBusString *buffer1,
218  int start1,
219  int len1,
220  const DBusString *buffer2,
221  int start2,
222  int len2);
223 
225  DBusString *buffer,
226  int count,
227  int *fds,
228  unsigned int *n_fds);
229 DBUS_PRIVATE_EXPORT
230 int _dbus_write_socket_with_unix_fds (DBusSocket fd,
231  const DBusString *buffer,
232  int start,
233  int len,
234  const int *fds,
235  int n_fds);
236 int _dbus_write_socket_with_unix_fds_two (DBusSocket fd,
237  const DBusString *buffer1,
238  int start1,
239  int len1,
240  const DBusString *buffer2,
241  int start2,
242  int len2,
243  const int *fds,
244  int n_fds);
245 
246 DBusSocket _dbus_connect_tcp_socket (const char *host,
247  const char *port,
248  const char *family,
249  DBusError *error);
250 DBusSocket _dbus_connect_tcp_socket_with_nonce (const char *host,
251  const char *port,
252  const char *family,
253  const char *noncefile,
254  DBusError *error);
255 int _dbus_listen_tcp_socket (const char *host,
256  const char *port,
257  const char *family,
258  DBusString *retport,
259  DBusSocket **fds_p,
260  DBusError *error);
262 
264  DBusCredentials *credentials,
265  DBusError *error);
267  DBusError *error);
268 
270  const DBusString *username);
272 DBUS_PRIVATE_EXPORT
274 
276  dbus_uid_t *uid_p);
278  dbus_gid_t *gid_p);
280  dbus_gid_t **group_ids,
281  int *n_group_ids);
283  DBusError *error);
285 dbus_bool_t _dbus_windows_user_is_process_owner (const char *windows_sid);
286 
288  DBusCredentials *credentials);
289 
290 dbus_bool_t _dbus_daemon_is_session_bus_address_published (const char *scope);
291 
292 dbus_bool_t _dbus_daemon_publish_session_bus_address (const char* address, const char* shm_name);
293 
294 void _dbus_daemon_unpublish_session_bus_address (void);
295 
297 
301 typedef struct DBusAtomic DBusAtomic;
302 
307 {
308 #ifdef DBUS_WIN
309  volatile long value;
310 #else
311  volatile dbus_int32_t value;
312 #endif
313 };
314 
315 DBUS_PRIVATE_EXPORT
317 DBUS_PRIVATE_EXPORT
319 DBUS_PRIVATE_EXPORT
321 
322 #ifdef DBUS_WIN
323 
324 /* On Windows, you can only poll sockets. We emulate Unix poll() using
325  * select(), so it doesn't matter what precise type we put in DBusPollFD;
326  * use DBusSocket so that the compiler can check we are doing it right.
327  */
328 typedef DBusSocket DBusPollable;
329 # define DBUS_POLLABLE_FORMAT "Iu"
330 
331 static inline DBusPollable
332 _dbus_socket_get_pollable (DBusSocket s) { return s; }
333 
334 static inline SOCKET
335 _dbus_pollable_printable (DBusPollable p) { return p.sock; }
336 
337 static inline dbus_bool_t
338 _dbus_pollable_is_valid (DBusPollable p) { return _dbus_socket_is_valid (p); }
339 
340 static inline void
341 _dbus_pollable_invalidate (DBusPollable *p) { _dbus_socket_invalidate (p); }
342 
343 static inline dbus_bool_t
344 _dbus_pollable_equals (DBusPollable a, DBusPollable b) { return a.sock == b.sock; }
345 
346 #else /* !DBUS_WIN */
347 
348 /* On Unix, you can poll sockets, pipes, etc., and we must put exactly
349  * "int" in DBusPollFD because we're relying on its layout exactly matching
350  * struct pollfd. (This is silly, and one day we should use a better
351  * abstraction.)
352  */
353 typedef int DBusPollable;
354 # define DBUS_POLLABLE_FORMAT "d"
355 
356 static inline DBusPollable
357 _dbus_socket_get_pollable (DBusSocket s) { return s.fd; }
358 
359 static inline int
360 _dbus_pollable_printable (DBusPollable p) { return p; }
361 
362 static inline dbus_bool_t
363 _dbus_pollable_is_valid (DBusPollable p) { return p >= 0; }
364 
365 static inline void
366 _dbus_pollable_invalidate (DBusPollable *p) { *p = -1; }
367 
368 static inline dbus_bool_t
369 _dbus_pollable_equals (DBusPollable a, DBusPollable b) { return a == b; }
370 
371 #endif /* !DBUS_WIN */
372 
373 #if defined(HAVE_POLL) && !defined(BROKEN_POLL)
374 
378 typedef struct pollfd DBusPollFD;
379 
381 #define _DBUS_POLLIN POLLIN
382 
383 #define _DBUS_POLLPRI POLLPRI
384 
385 #define _DBUS_POLLOUT POLLOUT
386 
387 #define _DBUS_POLLERR POLLERR
388 
389 #define _DBUS_POLLHUP POLLHUP
390 
391 #define _DBUS_POLLNVAL POLLNVAL
392 #else
393 /* Emulate poll() via select(). Because we aren't really going to call
394  * poll(), any similarly-shaped struct is acceptable, and any power of 2
395  * will do for the events/revents; these values happen to match Linux
396  * and *BSD. */
397 typedef struct
398 {
399  DBusPollable fd;
400  short events;
401  short revents;
402 } DBusPollFD;
403 
405 #define _DBUS_POLLIN 0x0001
406 
407 #define _DBUS_POLLPRI 0x0002
408 
409 #define _DBUS_POLLOUT 0x0004
410 
411 #define _DBUS_POLLERR 0x0008
412 
413 #define _DBUS_POLLHUP 0x0010
414 
415 #define _DBUS_POLLNVAL 0x0020
416 #endif
417 
418 DBUS_PRIVATE_EXPORT
419 int _dbus_poll (DBusPollFD *fds,
420  int n_fds,
421  int timeout_milliseconds);
422 
423 DBUS_PRIVATE_EXPORT
424 void _dbus_sleep_milliseconds (int milliseconds);
425 
426 DBUS_PRIVATE_EXPORT
427 void _dbus_get_monotonic_time (long *tv_sec,
428  long *tv_usec);
429 
430 DBUS_PRIVATE_EXPORT
431 void _dbus_get_real_time (long *tv_sec,
432  long *tv_usec);
433 
437 DBUS_PRIVATE_EXPORT
439  DBusError *error);
440 DBUS_PRIVATE_EXPORT
442  DBusError *error);
443 DBUS_PRIVATE_EXPORT
445  DBusError *error);
446 
447 DBUS_PRIVATE_EXPORT
449  const DBusString *next_component);
451  DBusString *dirname);
452 DBUS_PRIVATE_EXPORT
454 
458  DBusError *error);
459 
462 
464 typedef struct DBusDirIter DBusDirIter;
465 
467  DBusError *error);
469  DBusString *filename,
470  DBusError *error);
472 
474  DBusError *error);
475 
476 DBUS_PRIVATE_EXPORT
477 const char* _dbus_get_tmpdir (void);
478 
482 _DBUS_GNUC_WARN_UNUSED_RESULT
484  int n_bytes,
485  DBusError *error);
487  int n_bytes,
488  DBusError *error);
489 DBUS_PRIVATE_EXPORT
491  int n_bytes,
492  DBusError *error);
493 
494 DBUS_PRIVATE_EXPORT
495 const char* _dbus_error_from_errno (int error_number);
496 DBUS_PRIVATE_EXPORT
497 const char* _dbus_error_from_system_errno (void);
498 
499 int _dbus_save_socket_errno (void);
500 void _dbus_restore_socket_errno (int saved_errno);
501 void _dbus_set_errno_to_zero (void);
507 DBUS_PRIVATE_EXPORT
508 const char* _dbus_strerror_from_errno (void);
509 
510 void _dbus_disable_sigpipe (void);
511 
512 DBUS_PRIVATE_EXPORT
513 void _dbus_exit (int code) _DBUS_GNUC_NORETURN;
514 
515 DBUS_PRIVATE_EXPORT
516 int _dbus_printf_string_upper_bound (const char *format,
517  va_list args) _DBUS_GNUC_PRINTF (1, 0);
518 
519 #ifdef DBUS_ENABLE_VERBOSE_MODE
520 DBUS_PRIVATE_EXPORT
521 void _dbus_print_thread (void);
522 #endif
523 
527 typedef struct
528 {
529  unsigned long mode;
530  unsigned long nlink;
531  dbus_uid_t uid;
532  dbus_gid_t gid;
533  unsigned long size;
534  unsigned long atime;
535  unsigned long mtime;
536  unsigned long ctime;
537 } DBusStat;
538 
539 dbus_bool_t _dbus_stat (const DBusString *filename,
540  DBusStat *statbuf,
541  DBusError *error);
542 DBUS_PRIVATE_EXPORT
544  DBusSocket *fd2,
545  dbus_bool_t blocking,
546  DBusError *error);
547 
548 DBUS_PRIVATE_EXPORT
549 void _dbus_print_backtrace (void);
550 
552  DBusPipe *print_pid_pipe,
553  DBusError *error,
554  dbus_bool_t keep_umask);
555 
556 dbus_bool_t _dbus_verify_daemon_user (const char *user);
557 dbus_bool_t _dbus_change_to_daemon_user (const char *user,
558  DBusError *error);
559 
561  DBusPipe *print_pid_pipe,
562  dbus_pid_t pid_to_write,
563  DBusError *error);
564 
565 dbus_bool_t _dbus_command_for_pid (unsigned long pid,
566  DBusString *str,
567  int max_len,
568  DBusError *error);
569 
570 dbus_bool_t _dbus_user_at_console (const char *username,
571  DBusError *error);
572 
573 typedef enum {
574  DBUS_LOG_FLAGS_STDERR = (1 << 0),
575  DBUS_LOG_FLAGS_SYSTEM_LOG = (1 << 1)
576 } DBusLogFlags;
577 
578 DBUS_PRIVATE_EXPORT
579 void _dbus_init_system_log (const char *tag,
580  DBusLogFlags flags);
581 
582 typedef enum {
583  DBUS_SYSTEM_LOG_INFO,
584  DBUS_SYSTEM_LOG_WARNING,
585  DBUS_SYSTEM_LOG_SECURITY,
586  DBUS_SYSTEM_LOG_ERROR
587 } DBusSystemLogSeverity;
588 
589 DBUS_PRIVATE_EXPORT
590 void _dbus_log (DBusSystemLogSeverity severity,
591  const char *msg,
592  ...) _DBUS_GNUC_PRINTF (2, 3);
593 DBUS_PRIVATE_EXPORT
594 void _dbus_logv (DBusSystemLogSeverity severity,
595  const char *msg,
596  va_list args) _DBUS_GNUC_PRINTF (2, 0);
597 
598 /* Define DBUS_VA_COPY() to do the right thing for copying va_list variables.
599  * config.h may have already defined DBUS_VA_COPY as va_copy or __va_copy.
600  */
601 #if !defined (DBUS_VA_COPY)
602 # if defined (__GNUC__) && defined (__PPC__) && (defined (_CALL_SYSV) || defined (_WIN32))
603 # define DBUS_VA_COPY(ap1, ap2) (*(ap1) = *(ap2))
604 # elif defined (DBUS_VA_COPY_AS_ARRAY)
605 # define DBUS_VA_COPY(ap1, ap2) memcpy ((ap1), (ap2), sizeof (va_list))
606 # else /* va_list is a pointer */
607 # define DBUS_VA_COPY(ap1, ap2) ((ap1) = (ap2))
608 # endif /* va_list is a pointer */
609 #endif /* !DBUS_VA_COPY */
610 
611 
616 #define _DBUS_BYTE_OF_PRIMITIVE(p, i) \
617  (((const char*)&(p))[(i)])
618 
623 #define _DBUS_DOUBLES_BITWISE_EQUAL(a, b) \
624  (_DBUS_BYTE_OF_PRIMITIVE (a, 0) == _DBUS_BYTE_OF_PRIMITIVE (b, 0) && \
625  _DBUS_BYTE_OF_PRIMITIVE (a, 1) == _DBUS_BYTE_OF_PRIMITIVE (b, 1) && \
626  _DBUS_BYTE_OF_PRIMITIVE (a, 2) == _DBUS_BYTE_OF_PRIMITIVE (b, 2) && \
627  _DBUS_BYTE_OF_PRIMITIVE (a, 3) == _DBUS_BYTE_OF_PRIMITIVE (b, 3) && \
628  _DBUS_BYTE_OF_PRIMITIVE (a, 4) == _DBUS_BYTE_OF_PRIMITIVE (b, 4) && \
629  _DBUS_BYTE_OF_PRIMITIVE (a, 5) == _DBUS_BYTE_OF_PRIMITIVE (b, 5) && \
630  _DBUS_BYTE_OF_PRIMITIVE (a, 6) == _DBUS_BYTE_OF_PRIMITIVE (b, 6) && \
631  _DBUS_BYTE_OF_PRIMITIVE (a, 7) == _DBUS_BYTE_OF_PRIMITIVE (b, 7))
632 
633 dbus_bool_t _dbus_get_autolaunch_address (const char *scope,
634  DBusString *address,
635  DBusError *error);
636 
638  DBusString *address,
639  DBusError *error);
640 
644 typedef union DBusGUID DBusGUID;
645 
646 DBUS_PRIVATE_EXPORT
648  dbus_bool_t create_if_not_found,
649  DBusError *error);
650 
657 
662 
667 
668 DBUS_PRIVATE_EXPORT
670  const char *suffix,
671  DBusList **dir_list);
672 
673 unsigned long _dbus_pid_for_log (void);
674 
675 /* FIXME move back to dbus-sysdeps-unix.h probably -
676  * the PID file handling just needs a little more abstraction
677  * in the bus daemon first.
678  */
679 DBUS_PRIVATE_EXPORT
680 dbus_pid_t _dbus_getpid (void);
681 
682 DBUS_PRIVATE_EXPORT
683 dbus_uid_t _dbus_getuid (void);
684 
685 DBUS_PRIVATE_EXPORT
686 void _dbus_flush_caches (void);
687 
689 
690 /* Do not set this too high: it is a denial-of-service risk.
691  * See <https://bugs.freedesktop.org/show_bug.cgi?id=82820>
692  *
693  * (This needs to be in the non-Unix-specific header so that
694  * the config-parser can use it.)
695  */
696 #define DBUS_DEFAULT_MESSAGE_UNIX_FDS 16
697 
698 typedef struct DBusRLimit DBusRLimit;
699 
700 DBusRLimit *_dbus_rlimit_save_fd_limit (DBusError *error);
701 dbus_bool_t _dbus_rlimit_raise_fd_limit (DBusError *error);
702 dbus_bool_t _dbus_rlimit_restore_fd_limit (DBusRLimit *saved,
703  DBusError *error);
704 void _dbus_rlimit_free (DBusRLimit *lim);
705 
706 #ifdef DBUS_ENABLE_EMBEDDED_TESTS
707 _DBUS_GNUC_WARN_UNUSED_RESULT
708 dbus_bool_t _dbus_test_append_different_uid (DBusString *uid);
709 
710 #ifdef DBUS_UNIX
711 _DBUS_GNUC_WARN_UNUSED_RESULT
712 dbus_bool_t _dbus_test_append_different_username (DBusString *username);
713 #endif
714 #endif /* DBUS_ENABLE_EMBEDDED_TESTS */
715 
719 
720 
721 #ifdef DBUS_WIN
722 #include "dbus-sysdeps-win.h"
723 #endif
724 
725 #endif /* DBUS_SYSDEPS_H */