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 
95 DBUS_BEGIN_DECLS
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 
106 /** An opaque list type */
107 typedef struct DBusList DBusList;
108 
109 /** Object that contains a list of credentials such as UNIX or Windows user ID */
110 typedef struct DBusCredentials DBusCredentials;
111 
112 /** A wrapper around a pipe descriptor or handle */
113 typedef struct DBusPipe DBusPipe;
114 
115 /**
116  * @addtogroup DBusSysdeps
117  *
118  * @{
119  */
120 
121 DBUS_PRIVATE_EXPORT
122 void _dbus_abort (void) _DBUS_GNUC_NORETURN;
123 
124 dbus_bool_t _dbus_check_setuid (void);
125 DBUS_PRIVATE_EXPORT
126 const char* _dbus_getenv (const char *varname);
127 DBUS_PRIVATE_EXPORT
128 dbus_bool_t _dbus_clearenv (void);
129 char **     _dbus_get_environment (void);
130 
131 /** A process ID */
132 typedef unsigned long dbus_pid_t;
133 /** A user ID */
134 typedef unsigned long dbus_uid_t;
135 /** A group ID */
136 typedef unsigned long dbus_gid_t;
137 
138 /** an invalid PID used to represent an uninitialized dbus_pid_t field */
139 #define DBUS_PID_UNSET ((dbus_pid_t) -1)
140 /** an invalid UID used to represent an uninitialized dbus_uid_t field */
141 #define DBUS_UID_UNSET ((dbus_uid_t) -1)
142 /** an invalid GID used to represent an uninitialized dbus_gid_t field */
143 #define DBUS_GID_UNSET ((dbus_gid_t) -1)
144 
145 /** an appropriate printf format for dbus_pid_t */
146 #define DBUS_PID_FORMAT "%lu"
147 /** an appropriate printf format for dbus_uid_t */
148 #define DBUS_UID_FORMAT "%lu"
149 /** an appropriate printf format for dbus_gid_t */
150 #define DBUS_GID_FORMAT "%lu"
151 
152 /**
153  * Socket interface
154  */
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
_dbus_socket_printable(DBusSocket s)162 _dbus_socket_printable (DBusSocket s) { return s.sock; }
163 
164 static inline dbus_bool_t
_dbus_socket_is_valid(DBusSocket s)165 _dbus_socket_is_valid (DBusSocket s) { return s.sock != INVALID_SOCKET; }
166 
167 static inline void
_dbus_socket_invalidate(DBusSocket * s)168 _dbus_socket_invalidate (DBusSocket *s) { s->sock = INVALID_SOCKET; }
169 
170 static inline int
_dbus_socket_get_int(DBusSocket s)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
_dbus_socket_printable(DBusSocket s)180 _dbus_socket_printable (DBusSocket s) { return s.fd; }
181 
182 static inline dbus_bool_t
_dbus_socket_is_valid(DBusSocket s)183 _dbus_socket_is_valid (DBusSocket s) { return s.fd >= 0; }
184 
185 static inline void
_dbus_socket_invalidate(DBusSocket * s)186 _dbus_socket_invalidate (DBusSocket *s) { s->fd = -1; }
187 
188 static inline int
_dbus_socket_get_int(DBusSocket s)189 _dbus_socket_get_int (DBusSocket s) { return s.fd; }
190 
191 #endif /* not DBUS_WIN */
192 
193 static inline DBusSocket
_dbus_socket_get_invalid(void)194 _dbus_socket_get_invalid (void)
195 {
196   DBusSocket s = DBUS_SOCKET_INIT;
197 
198   return s;
199 }
200 
201 dbus_bool_t _dbus_set_socket_nonblocking (DBusSocket      fd,
202                                           DBusError      *error);
203 
204 DBUS_PRIVATE_EXPORT
205 dbus_bool_t _dbus_close_socket     (DBusSocket        fd,
206                                     DBusError        *error);
207 DBUS_PRIVATE_EXPORT
208 int         _dbus_read_socket      (DBusSocket        fd,
209                                     DBusString       *buffer,
210                                     int               count);
211 DBUS_PRIVATE_EXPORT
212 int         _dbus_write_socket     (DBusSocket        fd,
213                                     const DBusString *buffer,
214                                     int               start,
215                                     int               len);
216 int         _dbus_write_socket_two (DBusSocket        fd,
217                                     const DBusString *buffer1,
218                                     int               start1,
219                                     int               len1,
220                                     const DBusString *buffer2,
221                                     int               start2,
222                                     int               len2);
223 
224 int _dbus_read_socket_with_unix_fds      (DBusSocket        fd,
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);
261 DBusSocket _dbus_accept       (DBusSocket      listen_fd);
262 
263 dbus_bool_t _dbus_read_credentials_socket (DBusSocket        client_fd,
264                                            DBusCredentials  *credentials,
265                                            DBusError        *error);
266 dbus_bool_t _dbus_send_credentials_socket (DBusSocket       server_fd,
267                                            DBusError       *error);
268 
269 dbus_bool_t _dbus_credentials_add_from_user            (DBusCredentials  *credentials,
270                                                         const DBusString *username);
271 dbus_bool_t _dbus_credentials_add_from_current_process (DBusCredentials  *credentials);
272 DBUS_PRIVATE_EXPORT
273 dbus_bool_t _dbus_append_user_from_current_process     (DBusString        *str);
274 
275 dbus_bool_t _dbus_parse_unix_user_from_config   (const DBusString  *username,
276                                                  dbus_uid_t        *uid_p);
277 dbus_bool_t _dbus_parse_unix_group_from_config  (const DBusString  *groupname,
278                                                  dbus_gid_t        *gid_p);
279 dbus_bool_t _dbus_unix_groups_from_uid          (dbus_uid_t         uid,
280                                                  dbus_gid_t       **group_ids,
281                                                  int               *n_group_ids);
282 dbus_bool_t _dbus_unix_user_is_at_console       (dbus_uid_t         uid,
283                                                  DBusError         *error);
284 dbus_bool_t _dbus_unix_user_is_process_owner    (dbus_uid_t         uid);
285 dbus_bool_t _dbus_windows_user_is_process_owner (const char        *windows_sid);
286 
287 dbus_bool_t _dbus_append_keyring_directory_for_credentials (DBusString      *directory,
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 
296 dbus_bool_t _dbus_socket_can_pass_unix_fd(DBusSocket fd);
297 
298 /** Opaque type representing an atomically-modifiable integer
299  * that can be used from multiple threads.
300  */
301 typedef struct DBusAtomic DBusAtomic;
302 
303 /**
304  * An atomic integer safe to increment or decrement from multiple threads.
305  */
306 struct DBusAtomic
307 {
308 #ifdef DBUS_WIN
309   volatile long value; /**< Value of the atomic integer. */
310 #else
311   volatile dbus_int32_t value; /**< Value of the atomic integer. */
312 #endif
313 };
314 
315 DBUS_PRIVATE_EXPORT
316 dbus_int32_t _dbus_atomic_inc (DBusAtomic *atomic);
317 DBUS_PRIVATE_EXPORT
318 dbus_int32_t _dbus_atomic_dec (DBusAtomic *atomic);
319 DBUS_PRIVATE_EXPORT
320 dbus_int32_t _dbus_atomic_get (DBusAtomic *atomic);
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
_dbus_socket_get_pollable(DBusSocket s)332 _dbus_socket_get_pollable (DBusSocket s) { return s; }
333 
334 static inline SOCKET
_dbus_pollable_printable(DBusPollable p)335 _dbus_pollable_printable (DBusPollable p) { return p.sock; }
336 
337 static inline dbus_bool_t
_dbus_pollable_is_valid(DBusPollable p)338 _dbus_pollable_is_valid (DBusPollable p) { return _dbus_socket_is_valid (p); }
339 
340 static inline void
_dbus_pollable_invalidate(DBusPollable * p)341 _dbus_pollable_invalidate (DBusPollable *p) { _dbus_socket_invalidate (p); }
342 
343 static inline dbus_bool_t
_dbus_pollable_equals(DBusPollable a,DBusPollable b)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
_dbus_socket_get_pollable(DBusSocket s)357 _dbus_socket_get_pollable (DBusSocket s) { return s.fd; }
358 
359 static inline int
_dbus_pollable_printable(DBusPollable p)360 _dbus_pollable_printable (DBusPollable p) { return p; }
361 
362 static inline dbus_bool_t
_dbus_pollable_is_valid(DBusPollable p)363 _dbus_pollable_is_valid (DBusPollable p) { return p >= 0; }
364 
365 static inline void
_dbus_pollable_invalidate(DBusPollable * p)366 _dbus_pollable_invalidate (DBusPollable *p) { *p = -1; }
367 
368 static inline dbus_bool_t
_dbus_pollable_equals(DBusPollable a,DBusPollable b)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 /**
375  * A portable struct pollfd wrapper, or an emulation of struct pollfd
376  * on platforms where poll() is missing or broken.
377  */
378 typedef struct pollfd DBusPollFD;
379 
380 /** There is data to read */
381 #define _DBUS_POLLIN      POLLIN
382 /** There is urgent data to read */
383 #define _DBUS_POLLPRI     POLLPRI
384 /** Writing now will not block */
385 #define _DBUS_POLLOUT     POLLOUT
386 /** Error condition */
387 #define _DBUS_POLLERR     POLLERR
388 /** Hung up */
389 #define _DBUS_POLLHUP     POLLHUP
390 /** Invalid request: fd not open */
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;   /**< File descriptor */
400   short events;      /**< Events to poll for */
401   short revents;     /**< Events that occurred */
402 } DBusPollFD;
403 
404 /** There is data to read */
405 #define _DBUS_POLLIN      0x0001
406 /** There is urgent data to read */
407 #define _DBUS_POLLPRI     0x0002
408 /** Writing now will not block */
409 #define _DBUS_POLLOUT     0x0004
410 /** Error condition */
411 #define _DBUS_POLLERR     0x0008
412 /** Hung up */
413 #define _DBUS_POLLHUP     0x0010
414 /** Invalid request: fd not open */
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 
434 /**
435  * directory interface
436  */
437 DBUS_PRIVATE_EXPORT
438 dbus_bool_t    _dbus_create_directory        (const DBusString *filename,
439                                               DBusError        *error);
440 DBUS_PRIVATE_EXPORT
441 dbus_bool_t    _dbus_ensure_directory        (const DBusString *filename,
442                                               DBusError        *error);
443 DBUS_PRIVATE_EXPORT
444 dbus_bool_t    _dbus_delete_directory        (const DBusString *filename,
445 					      DBusError        *error);
446 
447 DBUS_PRIVATE_EXPORT
448 dbus_bool_t _dbus_concat_dir_and_file (DBusString       *dir,
449                                        const DBusString *next_component);
450 dbus_bool_t _dbus_string_get_dirname  (const DBusString *filename,
451                                        DBusString       *dirname);
452 DBUS_PRIVATE_EXPORT
453 dbus_bool_t _dbus_path_is_absolute    (const DBusString *filename);
454 
455 dbus_bool_t _dbus_get_standard_session_servicedirs (DBusList **dirs);
456 dbus_bool_t _dbus_get_standard_system_servicedirs (DBusList **dirs);
457 dbus_bool_t _dbus_set_up_transient_session_servicedirs (DBusList  **dirs,
458                                                         DBusError  *error);
459 
460 dbus_bool_t _dbus_get_system_config_file  (DBusString *str);
461 dbus_bool_t _dbus_get_session_config_file (DBusString *str);
462 
463 /** Opaque type for reading a directory listing */
464 typedef struct DBusDirIter DBusDirIter;
465 
466 DBusDirIter* _dbus_directory_open          (const DBusString *filename,
467                                             DBusError        *error);
468 dbus_bool_t  _dbus_directory_get_next_file (DBusDirIter      *iter,
469                                             DBusString       *filename,
470                                             DBusError        *error);
471 void         _dbus_directory_close         (DBusDirIter      *iter);
472 
473 dbus_bool_t  _dbus_check_dir_is_private_to_user    (DBusString *dir,
474                                                     DBusError *error);
475 
476 DBUS_PRIVATE_EXPORT
477 const char* _dbus_get_tmpdir      (void);
478 
479 /**
480  * Random numbers
481  */
482 _DBUS_GNUC_WARN_UNUSED_RESULT
483 dbus_bool_t _dbus_generate_random_bytes_buffer (char       *buffer,
484                                                 int         n_bytes,
485                                                 DBusError  *error);
486 dbus_bool_t _dbus_generate_random_bytes        (DBusString *str,
487                                                 int         n_bytes,
488                                                 DBusError  *error);
489 DBUS_PRIVATE_EXPORT
490 dbus_bool_t _dbus_generate_random_ascii        (DBusString *str,
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);
502 dbus_bool_t _dbus_get_is_errno_eagain_or_ewouldblock (int e);
503 dbus_bool_t _dbus_get_is_errno_enomem                (int e);
504 dbus_bool_t _dbus_get_is_errno_eintr                 (int e);
505 dbus_bool_t _dbus_get_is_errno_epipe                 (int e);
506 dbus_bool_t _dbus_get_is_errno_etoomanyrefs          (int e);
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 
524 /**
525  * Portable struct with stat() results
526  */
527 typedef struct
528 {
529   unsigned long mode;  /**< File mode */
530   unsigned long nlink; /**< Number of hard links */
531   dbus_uid_t    uid;   /**< User owning file */
532   dbus_gid_t    gid;   /**< Group owning file */
533   unsigned long size;  /**< Size of file */
534   unsigned long atime; /**< Access time */
535   unsigned long mtime; /**< Modify time */
536   unsigned long ctime; /**< Creation time */
537 } DBusStat;
538 
539 dbus_bool_t _dbus_stat             (const DBusString *filename,
540                                     DBusStat         *statbuf,
541                                     DBusError        *error);
542 DBUS_PRIVATE_EXPORT
543 dbus_bool_t _dbus_socketpair (DBusSocket       *fd1,
544                               DBusSocket       *fd2,
545                               dbus_bool_t       blocking,
546                               DBusError        *error);
547 
548 DBUS_PRIVATE_EXPORT
549 void        _dbus_print_backtrace  (void);
550 
551 dbus_bool_t _dbus_become_daemon   (const DBusString *pidfile,
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 
560 dbus_bool_t _dbus_write_pid_to_file_and_pipe (const DBusString *pidfile,
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 
612 /**
613  * Casts a primitive C type to a byte array and then indexes
614  * a particular byte of the array.
615  */
616 #define _DBUS_BYTE_OF_PRIMITIVE(p, i) \
617     (((const char*)&(p))[(i)])
618 /** On x86 there is an 80-bit FPU, and if you do "a == b" it may have a
619  * or b in an 80-bit register, thus failing to compare the two 64-bit
620  * doubles for bitwise equality. So this macro compares the two doubles
621  * bitwise.
622  */
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 
637 dbus_bool_t _dbus_lookup_session_address (dbus_bool_t *supported,
638                                           DBusString  *address,
639                                           DBusError   *error);
640 
641 /** Type representing a universally unique ID
642  * @todo rename to UUID instead of GUID
643  */
644 typedef union DBusGUID DBusGUID;
645 
646 DBUS_PRIVATE_EXPORT
647 dbus_bool_t _dbus_read_local_machine_uuid   (DBusGUID         *machine_id,
648                                              dbus_bool_t       create_if_not_found,
649                                              DBusError        *error);
650 
651 /**
652  * Initialize threads as in dbus_threads_init_default(), appropriately
653  * for the platform.
654  * @returns #FALSE if no memory
655  */
656 dbus_bool_t _dbus_threads_init_platform_specific (void);
657 
658 /**
659  * Lock a static mutex used to protect _dbus_threads_init_platform_specific().
660  */
661 void _dbus_threads_lock_platform_specific (void);
662 
663 /**
664  * Undo _dbus_threads_lock_platform_specific().
665  */
666 void _dbus_threads_unlock_platform_specific (void);
667 
668 DBUS_PRIVATE_EXPORT
669 dbus_bool_t _dbus_split_paths_and_append (DBusString *dirs,
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 
688 dbus_bool_t _dbus_replace_install_prefix (DBusString *path);
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 
716 /** @} */
717 
718 DBUS_END_DECLS
719 
720 
721 #ifdef DBUS_WIN
722 #include "dbus-sysdeps-win.h"
723 #endif
724 
725 #endif /* DBUS_SYSDEPS_H */
726