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)
4 * Copyright (C) 2002, 2003 Red Hat, Inc.
5 * Copyright (C) 2003 CodeFactory AB
7 * Licensed under the Academic Free License version 2.1
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.
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.
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
25 #ifndef DBUS_SYSDEPS_H
26 #define DBUS_SYSDEPS_H
29 #warning Please include config.h before dbus-sysdeps.h
37 #ifdef HAVE_INTTYPES_H
41 #include <dbus/dbus-errors.h>
42 #include <dbus/dbus-file.h>
43 #include <dbus/dbus-string.h>
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.
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
55 * https://github.com/curl/curl/blob/master/m4/curl-functions.m4
57 * On unspecified older macOS versions, poll() failed if given a
58 * device node to poll.
60 * On macOS < 10.9, poll() with nfds=0 failed instead of waiting for
61 * the timeout and then succeeding.
63 * On macOS >= 10.12, poll() with nfds=0 succeeded immediately
64 * instead of waiting for the timeout, resulting in busy-looping.
66 * On Interix, poll() apparently only works for files in /proc.
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
77 /* AIX sys/poll.h does #define events reqevents, and other
78 * wonderousness, so must include sys/poll before declaring
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"
98 #define _DBUS_PATH_SEPARATOR ";"
100 #define _DBUS_PATH_SEPARATOR ":"
103 /* Forward declarations */
106 /** An opaque list type */
107 typedef struct DBusList DBusList;
109 /** Object that contains a list of credentials such as UNIX or Windows user ID */
110 typedef struct DBusCredentials DBusCredentials;
112 /** A wrapper around a pipe descriptor or handle */
113 typedef struct DBusPipe DBusPipe;
116 * @addtogroup DBusSysdeps
122 void _dbus_abort (void) _DBUS_GNUC_NORETURN;
124 dbus_bool_t _dbus_check_setuid (void);
126 const char* _dbus_getenv (const char *varname);
128 dbus_bool_t _dbus_clearenv (void);
129 char ** _dbus_get_environment (void);
132 typedef unsigned long dbus_pid_t;
134 typedef unsigned long dbus_uid_t;
136 typedef unsigned long dbus_gid_t;
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)
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"
157 typedef struct { SOCKET sock; } DBusSocket;
158 # define DBUS_SOCKET_FORMAT "Iu"
159 # define DBUS_SOCKET_INIT { INVALID_SOCKET }
162 _dbus_socket_printable (DBusSocket s) { return s.sock; }
164 static inline dbus_bool_t
165 _dbus_socket_is_valid (DBusSocket s) { return s.sock != INVALID_SOCKET; }
168 _dbus_socket_invalidate (DBusSocket *s) { s->sock = INVALID_SOCKET; }
171 _dbus_socket_get_int (DBusSocket s) { return (int)s.sock; }
173 #else /* not DBUS_WIN */
175 typedef struct { int fd; } DBusSocket;
176 # define DBUS_SOCKET_FORMAT "d"
177 # define DBUS_SOCKET_INIT { -1 }
180 _dbus_socket_printable (DBusSocket s) { return s.fd; }
182 static inline dbus_bool_t
183 _dbus_socket_is_valid (DBusSocket s) { return s.fd >= 0; }
186 _dbus_socket_invalidate (DBusSocket *s) { s->fd = -1; }
189 _dbus_socket_get_int (DBusSocket s) { return s.fd; }
191 #endif /* not DBUS_WIN */
193 static inline DBusSocket
194 _dbus_socket_get_invalid (void)
196 DBusSocket s = DBUS_SOCKET_INIT;
201 dbus_bool_t _dbus_set_socket_nonblocking (DBusSocket fd,
205 dbus_bool_t _dbus_close_socket (DBusSocket fd,
208 int _dbus_read_socket (DBusSocket fd,
212 int _dbus_write_socket (DBusSocket fd,
213 const DBusString *buffer,
216 int _dbus_write_socket_two (DBusSocket fd,
217 const DBusString *buffer1,
220 const DBusString *buffer2,
224 int _dbus_read_socket_with_unix_fds (DBusSocket fd,
228 unsigned int *n_fds);
230 int _dbus_write_socket_with_unix_fds (DBusSocket fd,
231 const DBusString *buffer,
236 int _dbus_write_socket_with_unix_fds_two (DBusSocket fd,
237 const DBusString *buffer1,
240 const DBusString *buffer2,
246 DBusSocket _dbus_connect_tcp_socket (const char *host,
250 DBusSocket _dbus_connect_tcp_socket_with_nonce (const char *host,
253 const char *noncefile,
255 int _dbus_listen_tcp_socket (const char *host,
261 DBusSocket _dbus_accept (DBusSocket listen_fd);
263 dbus_bool_t _dbus_read_credentials_socket (DBusSocket client_fd,
264 DBusCredentials *credentials,
266 dbus_bool_t _dbus_send_credentials_socket (DBusSocket server_fd,
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);
273 dbus_bool_t _dbus_append_user_from_current_process (DBusString *str);
275 dbus_bool_t _dbus_parse_unix_user_from_config (const DBusString *username,
277 dbus_bool_t _dbus_parse_unix_group_from_config (const DBusString *groupname,
279 dbus_bool_t _dbus_unix_groups_from_uid (dbus_uid_t uid,
280 dbus_gid_t **group_ids,
282 dbus_bool_t _dbus_unix_user_is_at_console (dbus_uid_t uid,
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);
287 dbus_bool_t _dbus_append_keyring_directory_for_credentials (DBusString *directory,
288 DBusCredentials *credentials);
290 dbus_bool_t _dbus_daemon_is_session_bus_address_published (const char *scope);
292 dbus_bool_t _dbus_daemon_publish_session_bus_address (const char* address, const char* shm_name);
294 void _dbus_daemon_unpublish_session_bus_address (void);
296 dbus_bool_t _dbus_socket_can_pass_unix_fd(DBusSocket fd);
298 /** Opaque type representing an atomically-modifiable integer
299 * that can be used from multiple threads.
301 typedef struct DBusAtomic DBusAtomic;
304 * An atomic integer safe to increment or decrement from multiple threads.
309 volatile long value; /**< Value of the atomic integer. */
311 volatile dbus_int32_t value; /**< Value of the atomic integer. */
316 dbus_int32_t _dbus_atomic_inc (DBusAtomic *atomic);
318 dbus_int32_t _dbus_atomic_dec (DBusAtomic *atomic);
320 dbus_int32_t _dbus_atomic_get (DBusAtomic *atomic);
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.
328 typedef DBusSocket DBusPollable;
329 # define DBUS_POLLABLE_FORMAT "Iu"
331 static inline DBusPollable
332 _dbus_socket_get_pollable (DBusSocket s) { return s; }
335 _dbus_pollable_printable (DBusPollable p) { return p.sock; }
337 static inline dbus_bool_t
338 _dbus_pollable_is_valid (DBusPollable p) { return _dbus_socket_is_valid (p); }
341 _dbus_pollable_invalidate (DBusPollable *p) { _dbus_socket_invalidate (p); }
343 static inline dbus_bool_t
344 _dbus_pollable_equals (DBusPollable a, DBusPollable b) { return a.sock == b.sock; }
346 #else /* !DBUS_WIN */
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
353 typedef int DBusPollable;
354 # define DBUS_POLLABLE_FORMAT "d"
356 static inline DBusPollable
357 _dbus_socket_get_pollable (DBusSocket s) { return s.fd; }
360 _dbus_pollable_printable (DBusPollable p) { return p; }
362 static inline dbus_bool_t
363 _dbus_pollable_is_valid (DBusPollable p) { return p >= 0; }
366 _dbus_pollable_invalidate (DBusPollable *p) { *p = -1; }
368 static inline dbus_bool_t
369 _dbus_pollable_equals (DBusPollable a, DBusPollable b) { return a == b; }
371 #endif /* !DBUS_WIN */
373 #if defined(HAVE_POLL) && !defined(BROKEN_POLL)
375 * A portable struct pollfd wrapper, or an emulation of struct pollfd
376 * on platforms where poll() is missing or broken.
378 typedef struct pollfd DBusPollFD;
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
389 #define _DBUS_POLLHUP POLLHUP
390 /** Invalid request: fd not open */
391 #define _DBUS_POLLNVAL POLLNVAL
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
399 DBusPollable fd; /**< File descriptor */
400 short events; /**< Events to poll for */
401 short revents; /**< Events that occurred */
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
413 #define _DBUS_POLLHUP 0x0010
414 /** Invalid request: fd not open */
415 #define _DBUS_POLLNVAL 0x0020
419 int _dbus_poll (DBusPollFD *fds,
421 int timeout_milliseconds);
424 void _dbus_sleep_milliseconds (int milliseconds);
427 void _dbus_get_monotonic_time (long *tv_sec,
431 void _dbus_get_real_time (long *tv_sec,
435 * directory interface
438 dbus_bool_t _dbus_create_directory (const DBusString *filename,
441 dbus_bool_t _dbus_ensure_directory (const DBusString *filename,
444 dbus_bool_t _dbus_delete_directory (const DBusString *filename,
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);
453 dbus_bool_t _dbus_path_is_absolute (const DBusString *filename);
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,
460 dbus_bool_t _dbus_get_system_config_file (DBusString *str);
461 dbus_bool_t _dbus_get_session_config_file (DBusString *str);
463 /** Opaque type for reading a directory listing */
464 typedef struct DBusDirIter DBusDirIter;
466 DBusDirIter* _dbus_directory_open (const DBusString *filename,
468 dbus_bool_t _dbus_directory_get_next_file (DBusDirIter *iter,
469 DBusString *filename,
471 void _dbus_directory_close (DBusDirIter *iter);
473 dbus_bool_t _dbus_check_dir_is_private_to_user (DBusString *dir,
477 const char* _dbus_get_tmpdir (void);
482 _DBUS_GNUC_WARN_UNUSED_RESULT
483 dbus_bool_t _dbus_generate_random_bytes_buffer (char *buffer,
486 dbus_bool_t _dbus_generate_random_bytes (DBusString *str,
490 dbus_bool_t _dbus_generate_random_ascii (DBusString *str,
495 const char* _dbus_error_from_errno (int error_number);
497 const char* _dbus_error_from_system_errno (void);
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);
508 const char* _dbus_strerror_from_errno (void);
510 void _dbus_disable_sigpipe (void);
513 void _dbus_exit (int code) _DBUS_GNUC_NORETURN;
516 int _dbus_printf_string_upper_bound (const char *format,
517 va_list args) _DBUS_GNUC_PRINTF (1, 0);
519 #ifdef DBUS_ENABLE_VERBOSE_MODE
521 void _dbus_print_thread (void);
525 * Portable struct with stat() results
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 */
539 dbus_bool_t _dbus_stat (const DBusString *filename,
543 dbus_bool_t _dbus_socketpair (DBusSocket *fd1,
545 dbus_bool_t blocking,
549 void _dbus_print_backtrace (void);
551 dbus_bool_t _dbus_become_daemon (const DBusString *pidfile,
552 DBusPipe *print_pid_pipe,
554 dbus_bool_t keep_umask);
556 dbus_bool_t _dbus_verify_daemon_user (const char *user);
557 dbus_bool_t _dbus_change_to_daemon_user (const char *user,
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,
565 dbus_bool_t _dbus_command_for_pid (unsigned long pid,
570 dbus_bool_t _dbus_user_at_console (const char *username,
574 DBUS_LOG_FLAGS_STDERR = (1 << 0),
575 DBUS_LOG_FLAGS_SYSTEM_LOG = (1 << 1)
579 void _dbus_init_system_log (const char *tag,
583 DBUS_SYSTEM_LOG_INFO,
584 DBUS_SYSTEM_LOG_WARNING,
585 DBUS_SYSTEM_LOG_SECURITY,
586 DBUS_SYSTEM_LOG_ERROR
587 } DBusSystemLogSeverity;
590 void _dbus_log (DBusSystemLogSeverity severity,
592 ...) _DBUS_GNUC_PRINTF (2, 3);
594 void _dbus_logv (DBusSystemLogSeverity severity,
596 va_list args) _DBUS_GNUC_PRINTF (2, 0);
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.
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 */
613 * Casts a primitive C type to a byte array and then indexes
614 * a particular byte of the array.
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
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))
633 dbus_bool_t _dbus_get_autolaunch_address (const char *scope,
637 dbus_bool_t _dbus_lookup_session_address (dbus_bool_t *supported,
641 /** Type representing a universally unique ID
642 * @todo rename to UUID instead of GUID
644 typedef union DBusGUID DBusGUID;
647 dbus_bool_t _dbus_read_local_machine_uuid (DBusGUID *machine_id,
648 dbus_bool_t create_if_not_found,
652 * Initialize threads as in dbus_threads_init_default(), appropriately
654 * @returns #FALSE if no memory
656 dbus_bool_t _dbus_threads_init_platform_specific (void);
659 * Lock a static mutex used to protect _dbus_threads_init_platform_specific().
661 void _dbus_threads_lock_platform_specific (void);
664 * Undo _dbus_threads_lock_platform_specific().
666 void _dbus_threads_unlock_platform_specific (void);
669 dbus_bool_t _dbus_split_paths_and_append (DBusString *dirs,
671 DBusList **dir_list);
673 unsigned long _dbus_pid_for_log (void);
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.
680 dbus_pid_t _dbus_getpid (void);
683 dbus_uid_t _dbus_getuid (void);
686 void _dbus_flush_caches (void);
688 dbus_bool_t _dbus_replace_install_prefix (DBusString *path);
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>
693 * (This needs to be in the non-Unix-specific header so that
694 * the config-parser can use it.)
696 #define DBUS_DEFAULT_MESSAGE_UNIX_FDS 16
698 typedef struct DBusRLimit DBusRLimit;
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,
704 void _dbus_rlimit_free (DBusRLimit *lim);
706 #ifdef DBUS_ENABLE_EMBEDDED_TESTS
707 _DBUS_GNUC_WARN_UNUSED_RESULT
708 dbus_bool_t _dbus_test_append_different_uid (DBusString *uid);
711 _DBUS_GNUC_WARN_UNUSED_RESULT
712 dbus_bool_t _dbus_test_append_different_username (DBusString *username);
714 #endif /* DBUS_ENABLE_EMBEDDED_TESTS */
722 #include "dbus-sysdeps-win.h"
725 #endif /* DBUS_SYSDEPS_H */