1 /* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
2 /* dbus-internals.c random utility stuff (internal to D-Bus implementation)
3 *
4 * Copyright (C) 2002, 2003 Red Hat, Inc.
5 *
6 * Licensed under the Academic Free License version 2.1
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License as published by
10 * the Free Software Foundation; either version 2 of the License, or
11 * (at your option) any later version.
12 *
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21 *
22 */
23
24 #include <config.h>
25 #include "dbus-internals.h"
26 #include "dbus-protocol.h"
27 #include "dbus-marshal-basic.h"
28 #include "dbus-test.h"
29 #include "dbus-valgrind-internal.h"
30 #include <stdio.h>
31 #include <stdarg.h>
32 #include <string.h>
33 #include <stdlib.h>
34 #ifdef DBUS_USE_OUTPUT_DEBUG_STRING
35 #include <windows.h>
36 #include <mbstring.h>
37 #endif
38
39 #ifdef DBUS_ANDROID_LOG
40 #define LOG_TAG "libdbus"
41 #include <cutils/log.h>
42 #endif /* DBUS_ANDROID_LOG */
43
44 /**
45 * @defgroup DBusInternals D-Bus secret internal implementation details
46 * @brief Documentation useful when developing or debugging D-Bus itself.
47 *
48 */
49
50 /**
51 * @defgroup DBusInternalsUtils Utilities and portability
52 * @ingroup DBusInternals
53 * @brief Utility functions (_dbus_assert(), _dbus_warn(), etc.)
54 * @{
55 */
56
57 /**
58 * @def _dbus_assert
59 *
60 * Aborts with an error message if the condition is false.
61 *
62 * @param condition condition which must be true.
63 */
64
65 /**
66 * @def _dbus_assert_not_reached
67 *
68 * Aborts with an error message if called.
69 * The given explanation will be printed.
70 *
71 * @param explanation explanation of what happened if the code was reached.
72 */
73
74 /**
75 * @def _DBUS_N_ELEMENTS
76 *
77 * Computes the number of elements in a fixed-size array using
78 * sizeof().
79 *
80 * @param array the array to count elements in.
81 */
82
83 /**
84 * @def _DBUS_POINTER_TO_INT
85 *
86 * Safely casts a void* to an integer; should only be used on void*
87 * that actually contain integers, for example one created with
88 * _DBUS_INT_TO_POINTER. Only guaranteed to preserve 32 bits.
89 * (i.e. it's used to store 32-bit ints in pointers, but
90 * can't be used to store 64-bit pointers in ints.)
91 *
92 * @param pointer pointer to extract an integer from.
93 */
94 /**
95 * @def _DBUS_INT_TO_POINTER
96 *
97 * Safely stuffs an integer into a pointer, to be extracted later with
98 * _DBUS_POINTER_TO_INT. Only guaranteed to preserve 32 bits.
99 *
100 * @param integer the integer to stuff into a pointer.
101 */
102 /**
103 * @def _DBUS_ZERO
104 *
105 * Sets all bits in an object to zero.
106 *
107 * @param object the object to be zeroed.
108 */
109 /**
110 * @def _DBUS_INT16_MIN
111 *
112 * Minimum value of type "int16"
113 */
114 /**
115 * @def _DBUS_INT16_MAX
116 *
117 * Maximum value of type "int16"
118 */
119 /**
120 * @def _DBUS_UINT16_MAX
121 *
122 * Maximum value of type "uint16"
123 */
124
125 /**
126 * @def _DBUS_INT32_MIN
127 *
128 * Minimum value of type "int32"
129 */
130 /**
131 * @def _DBUS_INT32_MAX
132 *
133 * Maximum value of type "int32"
134 */
135 /**
136 * @def _DBUS_UINT32_MAX
137 *
138 * Maximum value of type "uint32"
139 */
140
141 /**
142 * @def _DBUS_INT_MIN
143 *
144 * Minimum value of type "int"
145 */
146 /**
147 * @def _DBUS_INT_MAX
148 *
149 * Maximum value of type "int"
150 */
151 /**
152 * @def _DBUS_UINT_MAX
153 *
154 * Maximum value of type "uint"
155 */
156
157 /**
158 * @typedef DBusForeachFunction
159 *
160 * Used to iterate over each item in a collection, such as
161 * a DBusList.
162 */
163
164 /**
165 * @def _DBUS_LOCK_NAME
166 *
167 * Expands to name of a global lock variable.
168 */
169
170 /**
171 * @def _DBUS_DEFINE_GLOBAL_LOCK
172 *
173 * Defines a global lock variable with the given name.
174 * The lock must be added to the list to initialize
175 * in dbus_threads_init().
176 */
177
178 /**
179 * @def _DBUS_DECLARE_GLOBAL_LOCK
180 *
181 * Expands to declaration of a global lock defined
182 * with _DBUS_DEFINE_GLOBAL_LOCK.
183 * The lock must be added to the list to initialize
184 * in dbus_threads_init().
185 */
186
187 /**
188 * @def _DBUS_LOCK
189 *
190 * Locks a global lock
191 */
192
193 /**
194 * @def _DBUS_UNLOCK
195 *
196 * Unlocks a global lock
197 */
198
199 /**
200 * Fixed "out of memory" error message, just to avoid
201 * making up a different string every time and wasting
202 * space.
203 */
204 const char *_dbus_no_memory_message = "Not enough memory";
205
206 static dbus_bool_t warn_initted = FALSE;
207 static dbus_bool_t fatal_warnings = FALSE;
208 static dbus_bool_t fatal_warnings_on_check_failed = TRUE;
209
210 static void
init_warnings(void)211 init_warnings(void)
212 {
213 if (!warn_initted)
214 {
215 const char *s;
216 s = _dbus_getenv ("DBUS_FATAL_WARNINGS");
217 if (s && *s)
218 {
219 if (*s == '0')
220 {
221 fatal_warnings = FALSE;
222 fatal_warnings_on_check_failed = FALSE;
223 }
224 else if (*s == '1')
225 {
226 fatal_warnings = TRUE;
227 fatal_warnings_on_check_failed = TRUE;
228 }
229 else
230 {
231 fprintf(stderr, "DBUS_FATAL_WARNINGS should be set to 0 or 1 if set, not '%s'",
232 s);
233 }
234 }
235
236 warn_initted = TRUE;
237 }
238 }
239
240 /**
241 * Prints a warning message to stderr. Can optionally be made to exit
242 * fatally by setting DBUS_FATAL_WARNINGS, but this is rarely
243 * used. This function should be considered pretty much equivalent to
244 * fprintf(stderr). _dbus_warn_check_failed() on the other hand is
245 * suitable for use when a programming mistake has been made.
246 *
247 * @param format printf-style format string.
248 */
249 void
_dbus_warn(const char * format,...)250 _dbus_warn (const char *format,
251 ...)
252 {
253 va_list args;
254
255 if (!warn_initted)
256 init_warnings ();
257
258 va_start (args, format);
259 #ifdef DBUS_ANDROID_LOG
260 LOG_PRI_VA(ANDROID_LOG_WARN, LOG_TAG, format, args);
261 #else
262 vfprintf (stderr, format, args);
263 #endif /* DBUS_ANDROID_LOG */
264 va_end (args);
265
266 if (fatal_warnings)
267 {
268 fflush (stderr);
269 _dbus_abort ();
270 }
271 }
272
273 /**
274 * Prints a "critical" warning to stderr when an assertion fails;
275 * differs from _dbus_warn primarily in that it prefixes the pid and
276 * defaults to fatal. This should be used only when a programming
277 * error has been detected. (NOT for unavoidable errors that an app
278 * might handle - those should be returned as DBusError.) Calling this
279 * means "there is a bug"
280 */
281 void
_dbus_warn_check_failed(const char * format,...)282 _dbus_warn_check_failed(const char *format,
283 ...)
284 {
285 va_list args;
286
287 if (!warn_initted)
288 init_warnings ();
289
290 fprintf (stderr, "process %lu: ", _dbus_pid_for_log ());
291
292 va_start (args, format);
293 #ifdef DBUS_ANDROID_LOG
294 LOG_PRI_VA(ANDROID_LOG_ERROR, LOG_TAG, format, args);
295 #else
296 vfprintf (stderr, format, args);
297 #endif /* DBUS_ANDROID_LOG */
298 va_end (args);
299
300 if (fatal_warnings_on_check_failed)
301 {
302 fflush (stderr);
303 _dbus_abort ();
304 }
305 }
306
307 #ifdef DBUS_ENABLE_VERBOSE_MODE
308
309 static dbus_bool_t verbose_initted = FALSE;
310 static dbus_bool_t verbose = TRUE;
311
312 /** Whether to show the current thread in verbose messages */
313 #define PTHREAD_IN_VERBOSE 0
314 #if PTHREAD_IN_VERBOSE
315 #include <pthread.h>
316 #endif
317
318 #ifdef DBUS_USE_OUTPUT_DEBUG_STRING
319 static char module_name[1024];
320 #endif
321
322 static inline void
_dbus_verbose_init(void)323 _dbus_verbose_init (void)
324 {
325 if (!verbose_initted)
326 {
327 #ifdef DBUS_ANDROID_LOG
328 /* Don't bother checking environment variable - just print the
329 verbose logs (can still be disabled with DBUS_ENABLE_VERBOSE_MODE) */
330 verbose = TRUE;
331 #else
332 const char *p = _dbus_getenv ("DBUS_VERBOSE");
333 verbose = p != NULL && *p == '1';
334 #endif
335 verbose_initted = TRUE;
336 #ifdef DBUS_USE_OUTPUT_DEBUG_STRING
337 {
338 char *last_period, *last_slash;
339 GetModuleFileName(0,module_name,sizeof(module_name)-1);
340 last_period = _mbsrchr(module_name,'.');
341 if (last_period)
342 *last_period ='\0';
343 last_slash = _mbsrchr(module_name,'\\');
344 if (last_slash)
345 strcpy(module_name,last_slash+1);
346 strcat(module_name,": ");
347 }
348 #endif
349 }
350 }
351
352 /** @def DBUS_IS_DIR_SEPARATOR(c)
353 * macro for checking if character c is a patch separator
354 *
355 * @todo move to a header file so that others can use this too
356 */
357 #ifdef DBUS_WIN
358 #define DBUS_IS_DIR_SEPARATOR(c) (c == '\\' || c == '/')
359 #else
360 #define DBUS_IS_DIR_SEPARATOR(c) (c == '/')
361 #endif
362
363 /**
364 remove source root from file path
365 the source root is determined by
366 */
_dbus_file_path_extract_elements_from_tail(const char * file,int level)367 static char *_dbus_file_path_extract_elements_from_tail(const char *file,int level)
368 {
369 static int prefix = -1;
370
371 if (prefix == -1)
372 {
373 char *p = (char *)file + strlen(file);
374 int i = 0;
375 prefix = 0;
376 for (;p >= file;p--)
377 {
378 if (DBUS_IS_DIR_SEPARATOR(*p))
379 {
380 if (++i >= level)
381 {
382 prefix = p-file+1;
383 break;
384 }
385 }
386 }
387 }
388 return (char *)file+prefix;
389 }
390
391 /**
392 * Implementation of dbus_is_verbose() macro if built with verbose logging
393 * enabled.
394 * @returns whether verbose logging is active.
395 */
396 dbus_bool_t
_dbus_is_verbose_real(void)397 _dbus_is_verbose_real (void)
398 {
399 _dbus_verbose_init ();
400 return verbose;
401 }
402
403 /**
404 * Prints a warning message to stderr
405 * if the user has enabled verbose mode.
406 * This is the real function implementation,
407 * use _dbus_verbose() macro in code.
408 *
409 * @param format printf-style format string.
410 */
411 void
_dbus_verbose_real(const char * file,const int line,const char * function,const char * format,...)412 _dbus_verbose_real (
413 #ifdef DBUS_CPP_SUPPORTS_VARIABLE_MACRO_ARGUMENTS
414 const char *file,
415 const int line,
416 const char *function,
417 #endif
418 const char *format,
419 ...)
420 {
421 va_list args;
422 static dbus_bool_t need_pid = TRUE;
423 int len;
424
425 /* things are written a bit oddly here so that
426 * in the non-verbose case we just have the one
427 * conditional and return immediately.
428 */
429 if (!_dbus_is_verbose_real())
430 return;
431
432 #ifndef DBUS_USE_OUTPUT_DEBUG_STRING
433 /* Print out pid before the line */
434 if (need_pid)
435 {
436 #if PTHREAD_IN_VERBOSE
437 fprintf (stderr, "%lu: 0x%lx: ", _dbus_pid_for_log (), pthread_self ());
438 #else
439 fprintf (stderr, "%lu: ", _dbus_pid_for_log ());
440 #endif
441 }
442 #endif
443
444 /* Only print pid again if the next line is a new line */
445 len = strlen (format);
446 if (format[len-1] == '\n')
447 need_pid = TRUE;
448 else
449 need_pid = FALSE;
450
451 va_start (args, format);
452 #ifdef DBUS_USE_OUTPUT_DEBUG_STRING
453 {
454 char buf[1024];
455 strcpy(buf,module_name);
456 #ifdef DBUS_CPP_SUPPORTS_VARIABLE_MACRO_ARGUMENTS
457 sprintf (buf+strlen(buf), "[%s(%d):%s] ",_dbus_file_path_extract_elements_from_tail(file,2),line,function);
458 #endif
459 vsprintf (buf+strlen(buf),format, args);
460 va_end (args);
461 OutputDebugStringA(buf);
462 }
463 #else
464 #ifdef DBUS_CPP_SUPPORTS_VARIABLE_MACRO_ARGUMENTS
465 fprintf (stderr, "[%s(%d):%s] ",_dbus_file_path_extract_elements_from_tail(file,2),line,function);
466 #endif
467
468 #ifdef DBUS_ANDROID_LOG
469 LOG_PRI_VA(ANDROID_LOG_DEBUG, LOG_TAG, format, args);
470 #else
471 vfprintf (stderr, format, args);
472 #endif /* DBUS_ANDROID_LOG */
473 va_end (args);
474
475 fflush (stderr);
476 #endif
477 }
478
479 /**
480 * Reinitializes the verbose logging code, used
481 * as a hack in dbus-spawn.c so that a child
482 * process re-reads its pid
483 *
484 */
485 void
_dbus_verbose_reset_real(void)486 _dbus_verbose_reset_real (void)
487 {
488 verbose_initted = FALSE;
489 }
490
491 void
_dbus_trace_ref(const char * obj_name,void * obj,int old_refcount,int new_refcount,const char * why,const char * env_var,int * enabled)492 _dbus_trace_ref (const char *obj_name,
493 void *obj,
494 int old_refcount,
495 int new_refcount,
496 const char *why,
497 const char *env_var,
498 int *enabled)
499 {
500 _dbus_assert (obj_name != NULL);
501 _dbus_assert (obj != NULL);
502 _dbus_assert (old_refcount >= -1);
503 _dbus_assert (new_refcount >= -1);
504
505 if (old_refcount == -1)
506 {
507 _dbus_assert (new_refcount == -1);
508 }
509 else
510 {
511 _dbus_assert (new_refcount >= 0);
512 _dbus_assert (old_refcount >= 0);
513 _dbus_assert (old_refcount > 0 || new_refcount > 0);
514 }
515
516 _dbus_assert (why != NULL);
517 _dbus_assert (env_var != NULL);
518 _dbus_assert (enabled != NULL);
519
520 if (*enabled < 0)
521 {
522 const char *s = _dbus_getenv (env_var);
523
524 *enabled = FALSE;
525
526 if (s && *s)
527 {
528 if (*s == '0')
529 *enabled = FALSE;
530 else if (*s == '1')
531 *enabled = TRUE;
532 else
533 _dbus_warn ("%s should be 0 or 1 if set, not '%s'", env_var, s);
534 }
535 }
536
537 if (*enabled)
538 {
539 if (old_refcount == -1)
540 {
541 VALGRIND_PRINTF_BACKTRACE ("%s %p ref stolen (%s)",
542 obj_name, obj, why);
543 _dbus_verbose ("%s %p ref stolen (%s)",
544 obj_name, obj, why);
545 }
546 else
547 {
548 VALGRIND_PRINTF_BACKTRACE ("%s %p %d -> %d refs (%s)",
549 obj_name, obj,
550 old_refcount, new_refcount, why);
551 _dbus_verbose ("%s %p %d -> %d refs (%s)",
552 obj_name, obj, old_refcount, new_refcount, why);
553 }
554 }
555 }
556
557 #endif /* DBUS_ENABLE_VERBOSE_MODE */
558
559 /**
560 * Duplicates a string. Result must be freed with
561 * dbus_free(). Returns #NULL if memory allocation fails.
562 * If the string to be duplicated is #NULL, returns #NULL.
563 *
564 * @param str string to duplicate.
565 * @returns newly-allocated copy.
566 */
567 char*
_dbus_strdup(const char * str)568 _dbus_strdup (const char *str)
569 {
570 size_t len;
571 char *copy;
572
573 if (str == NULL)
574 return NULL;
575
576 len = strlen (str);
577
578 copy = dbus_malloc (len + 1);
579 if (copy == NULL)
580 return NULL;
581
582 memcpy (copy, str, len + 1);
583
584 return copy;
585 }
586
587 /**
588 * Duplicates a block of memory. Returns
589 * #NULL on failure.
590 *
591 * @param mem memory to copy
592 * @param n_bytes number of bytes to copy
593 * @returns the copy
594 */
595 void*
_dbus_memdup(const void * mem,size_t n_bytes)596 _dbus_memdup (const void *mem,
597 size_t n_bytes)
598 {
599 void *copy;
600
601 copy = dbus_malloc (n_bytes);
602 if (copy == NULL)
603 return NULL;
604
605 memcpy (copy, mem, n_bytes);
606
607 return copy;
608 }
609
610 /**
611 * Duplicates a string array. Result may be freed with
612 * dbus_free_string_array(). Returns #NULL if memory allocation fails.
613 * If the array to be duplicated is #NULL, returns #NULL.
614 *
615 * @param array array to duplicate.
616 * @returns newly-allocated copy.
617 */
618 char**
_dbus_dup_string_array(const char ** array)619 _dbus_dup_string_array (const char **array)
620 {
621 int len;
622 int i;
623 char **copy;
624
625 if (array == NULL)
626 return NULL;
627
628 for (len = 0; array[len] != NULL; ++len)
629 ;
630
631 copy = dbus_new0 (char*, len + 1);
632 if (copy == NULL)
633 return NULL;
634
635 i = 0;
636 while (i < len)
637 {
638 copy[i] = _dbus_strdup (array[i]);
639 if (copy[i] == NULL)
640 {
641 dbus_free_string_array (copy);
642 return NULL;
643 }
644
645 ++i;
646 }
647
648 return copy;
649 }
650
651 /**
652 * Checks whether a string array contains the given string.
653 *
654 * @param array array to search.
655 * @param str string to look for
656 * @returns #TRUE if array contains string
657 */
658 dbus_bool_t
_dbus_string_array_contains(const char ** array,const char * str)659 _dbus_string_array_contains (const char **array,
660 const char *str)
661 {
662 int i;
663
664 i = 0;
665 while (array[i] != NULL)
666 {
667 if (strcmp (array[i], str) == 0)
668 return TRUE;
669 ++i;
670 }
671
672 return FALSE;
673 }
674
675 /**
676 * Generates a new UUID. If you change how this is done,
677 * there's some text about it in the spec that should also change.
678 *
679 * @param uuid the uuid to initialize
680 */
681 void
_dbus_generate_uuid(DBusGUID * uuid)682 _dbus_generate_uuid (DBusGUID *uuid)
683 {
684 long now;
685
686 /* don't use monotonic time because the UUID may be saved to disk, e.g.
687 * it may persist across reboots
688 */
689 _dbus_get_real_time (&now, NULL);
690
691 uuid->as_uint32s[DBUS_UUID_LENGTH_WORDS - 1] = DBUS_UINT32_TO_BE (now);
692
693 _dbus_generate_random_bytes_buffer (uuid->as_bytes, DBUS_UUID_LENGTH_BYTES - 4);
694 }
695
696 /**
697 * Hex-encode a UUID.
698 *
699 * @param uuid the uuid
700 * @param encoded string to append hex uuid to
701 * @returns #FALSE if no memory
702 */
703 dbus_bool_t
_dbus_uuid_encode(const DBusGUID * uuid,DBusString * encoded)704 _dbus_uuid_encode (const DBusGUID *uuid,
705 DBusString *encoded)
706 {
707 DBusString binary;
708 _dbus_string_init_const_len (&binary, uuid->as_bytes, DBUS_UUID_LENGTH_BYTES);
709 return _dbus_string_hex_encode (&binary, 0, encoded, _dbus_string_get_length (encoded));
710 }
711
712 static dbus_bool_t
_dbus_read_uuid_file_without_creating(const DBusString * filename,DBusGUID * uuid,DBusError * error)713 _dbus_read_uuid_file_without_creating (const DBusString *filename,
714 DBusGUID *uuid,
715 DBusError *error)
716 {
717 DBusString contents;
718 DBusString decoded;
719 int end;
720
721 if (!_dbus_string_init (&contents))
722 {
723 _DBUS_SET_OOM (error);
724 return FALSE;
725 }
726
727 if (!_dbus_string_init (&decoded))
728 {
729 _dbus_string_free (&contents);
730 _DBUS_SET_OOM (error);
731 return FALSE;
732 }
733
734 if (!_dbus_file_get_contents (&contents, filename, error))
735 goto error;
736
737 _dbus_string_chop_white (&contents);
738
739 if (_dbus_string_get_length (&contents) != DBUS_UUID_LENGTH_HEX)
740 {
741 dbus_set_error (error, DBUS_ERROR_INVALID_FILE_CONTENT,
742 "UUID file '%s' should contain a hex string of length %d, not length %d, with no other text",
743 _dbus_string_get_const_data (filename),
744 DBUS_UUID_LENGTH_HEX,
745 _dbus_string_get_length (&contents));
746 goto error;
747 }
748
749 if (!_dbus_string_hex_decode (&contents, 0, &end, &decoded, 0))
750 {
751 _DBUS_SET_OOM (error);
752 goto error;
753 }
754
755 if (end == 0)
756 {
757 dbus_set_error (error, DBUS_ERROR_INVALID_FILE_CONTENT,
758 "UUID file '%s' contains invalid hex data",
759 _dbus_string_get_const_data (filename));
760 goto error;
761 }
762
763 if (_dbus_string_get_length (&decoded) != DBUS_UUID_LENGTH_BYTES)
764 {
765 dbus_set_error (error, DBUS_ERROR_INVALID_FILE_CONTENT,
766 "UUID file '%s' contains %d bytes of hex-encoded data instead of %d",
767 _dbus_string_get_const_data (filename),
768 _dbus_string_get_length (&decoded),
769 DBUS_UUID_LENGTH_BYTES);
770 goto error;
771 }
772
773 _dbus_string_copy_to_buffer (&decoded, uuid->as_bytes, DBUS_UUID_LENGTH_BYTES);
774
775 _dbus_string_free (&decoded);
776 _dbus_string_free (&contents);
777
778 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
779
780 return TRUE;
781
782 error:
783 _DBUS_ASSERT_ERROR_IS_SET (error);
784 _dbus_string_free (&contents);
785 _dbus_string_free (&decoded);
786 return FALSE;
787 }
788
789 static dbus_bool_t
_dbus_create_uuid_file_exclusively(const DBusString * filename,DBusGUID * uuid,DBusError * error)790 _dbus_create_uuid_file_exclusively (const DBusString *filename,
791 DBusGUID *uuid,
792 DBusError *error)
793 {
794 DBusString encoded;
795
796 if (!_dbus_string_init (&encoded))
797 {
798 _DBUS_SET_OOM (error);
799 return FALSE;
800 }
801
802 _dbus_generate_uuid (uuid);
803
804 if (!_dbus_uuid_encode (uuid, &encoded))
805 {
806 _DBUS_SET_OOM (error);
807 goto error;
808 }
809
810 if (!_dbus_string_append_byte (&encoded, '\n'))
811 {
812 _DBUS_SET_OOM (error);
813 goto error;
814 }
815
816 if (!_dbus_string_save_to_file (&encoded, filename, TRUE, error))
817 goto error;
818
819 _dbus_string_free (&encoded);
820
821 _DBUS_ASSERT_ERROR_IS_CLEAR (error);
822 return TRUE;
823
824 error:
825 _DBUS_ASSERT_ERROR_IS_SET (error);
826 _dbus_string_free (&encoded);
827 return FALSE;
828 }
829
830 /**
831 * Reads (and optionally writes) a uuid to a file. Initializes the uuid
832 * unless an error is returned.
833 *
834 * @param filename the name of the file
835 * @param uuid uuid to be initialized with the loaded uuid
836 * @param create_if_not_found #TRUE to create a new uuid and save it if the file doesn't exist
837 * @param error the error return
838 * @returns #FALSE if the error is set
839 */
840 dbus_bool_t
_dbus_read_uuid_file(const DBusString * filename,DBusGUID * uuid,dbus_bool_t create_if_not_found,DBusError * error)841 _dbus_read_uuid_file (const DBusString *filename,
842 DBusGUID *uuid,
843 dbus_bool_t create_if_not_found,
844 DBusError *error)
845 {
846 DBusError read_error = DBUS_ERROR_INIT;
847
848 if (_dbus_read_uuid_file_without_creating (filename, uuid, &read_error))
849 return TRUE;
850
851 if (!create_if_not_found)
852 {
853 dbus_move_error (&read_error, error);
854 return FALSE;
855 }
856
857 /* If the file exists and contains junk, we want to keep that error
858 * message instead of overwriting it with a "file exists" error
859 * message when we try to write
860 */
861 if (dbus_error_has_name (&read_error, DBUS_ERROR_INVALID_FILE_CONTENT))
862 {
863 dbus_move_error (&read_error, error);
864 return FALSE;
865 }
866 else
867 {
868 dbus_error_free (&read_error);
869 return _dbus_create_uuid_file_exclusively (filename, uuid, error);
870 }
871 }
872
873 _DBUS_DEFINE_GLOBAL_LOCK (machine_uuid);
874 static int machine_uuid_initialized_generation = 0;
875 static DBusGUID machine_uuid;
876
877 /**
878 * Gets the hex-encoded UUID of the machine this function is
879 * executed on. This UUID is guaranteed to be the same for a given
880 * machine at least until it next reboots, though it also
881 * makes some effort to be the same forever, it may change if the
882 * machine is reconfigured or its hardware is modified.
883 *
884 * @param uuid_str string to append hex-encoded machine uuid to
885 * @returns #FALSE if no memory
886 */
887 dbus_bool_t
_dbus_get_local_machine_uuid_encoded(DBusString * uuid_str)888 _dbus_get_local_machine_uuid_encoded (DBusString *uuid_str)
889 {
890 dbus_bool_t ok;
891
892 _DBUS_LOCK (machine_uuid);
893 if (machine_uuid_initialized_generation != _dbus_current_generation)
894 {
895 DBusError error = DBUS_ERROR_INIT;
896
897 if (!_dbus_read_local_machine_uuid (&machine_uuid, FALSE,
898 &error))
899 {
900 #ifndef DBUS_BUILD_TESTS
901 /* For the test suite, we may not be installed so just continue silently
902 * here. But in a production build, we want to be nice and loud about
903 * this.
904 */
905 _dbus_warn_check_failed ("D-Bus library appears to be incorrectly set up; failed to read machine uuid: %s\n"
906 "See the manual page for dbus-uuidgen to correct this issue.\n",
907 error.message);
908 #endif
909
910 dbus_error_free (&error);
911
912 _dbus_generate_uuid (&machine_uuid);
913 }
914 }
915
916 ok = _dbus_uuid_encode (&machine_uuid, uuid_str);
917
918 _DBUS_UNLOCK (machine_uuid);
919
920 return ok;
921 }
922
923 #ifndef DBUS_DISABLE_CHECKS
924 /** String used in _dbus_return_if_fail macro */
925 const char *_dbus_return_if_fail_warning_format =
926 "arguments to %s() were incorrect, assertion \"%s\" failed in file %s line %d.\n"
927 "This is normally a bug in some application using the D-Bus library.\n";
928 #endif
929
930 #ifndef DBUS_DISABLE_ASSERT
931 /**
932 * Internals of _dbus_assert(); it's a function
933 * rather than a macro with the inline code so
934 * that the assertion failure blocks don't show up
935 * in test suite coverage, and to shrink code size.
936 *
937 * @param condition TRUE if assertion succeeded
938 * @param condition_text condition as a string
939 * @param file file the assertion is in
940 * @param line line the assertion is in
941 * @param func function the assertion is in
942 */
943 void
_dbus_real_assert(dbus_bool_t condition,const char * condition_text,const char * file,int line,const char * func)944 _dbus_real_assert (dbus_bool_t condition,
945 const char *condition_text,
946 const char *file,
947 int line,
948 const char *func)
949 {
950 if (_DBUS_UNLIKELY (!condition))
951 {
952 _dbus_warn ("%lu: assertion failed \"%s\" file \"%s\" line %d function %s\n",
953 _dbus_pid_for_log (), condition_text, file, line, func);
954 _dbus_abort ();
955 }
956 }
957
958 /**
959 * Internals of _dbus_assert_not_reached(); it's a function
960 * rather than a macro with the inline code so
961 * that the assertion failure blocks don't show up
962 * in test suite coverage, and to shrink code size.
963 *
964 * @param explanation what was reached that shouldn't have been
965 * @param file file the assertion is in
966 * @param line line the assertion is in
967 */
968 void
_dbus_real_assert_not_reached(const char * explanation,const char * file,int line)969 _dbus_real_assert_not_reached (const char *explanation,
970 const char *file,
971 int line)
972 {
973 _dbus_warn ("File \"%s\" line %d process %lu should not have been reached: %s\n",
974 file, line, _dbus_pid_for_log (), explanation);
975 _dbus_abort ();
976 }
977 #endif /* DBUS_DISABLE_ASSERT */
978
979 #ifdef DBUS_BUILD_TESTS
980 static dbus_bool_t
run_failing_each_malloc(int n_mallocs,const char * description,DBusTestMemoryFunction func,void * data)981 run_failing_each_malloc (int n_mallocs,
982 const char *description,
983 DBusTestMemoryFunction func,
984 void *data)
985 {
986 n_mallocs += 10; /* fudge factor to ensure reallocs etc. are covered */
987
988 while (n_mallocs >= 0)
989 {
990 _dbus_set_fail_alloc_counter (n_mallocs);
991
992 _dbus_verbose ("\n===\n%s: (will fail malloc %d with %d failures)\n===\n",
993 description, n_mallocs,
994 _dbus_get_fail_alloc_failures ());
995
996 if (!(* func) (data))
997 return FALSE;
998
999 n_mallocs -= 1;
1000 }
1001
1002 _dbus_set_fail_alloc_counter (_DBUS_INT_MAX);
1003
1004 return TRUE;
1005 }
1006
1007 /**
1008 * Tests how well the given function responds to out-of-memory
1009 * situations. Calls the function repeatedly, failing a different
1010 * call to malloc() each time. If the function ever returns #FALSE,
1011 * the test fails. The function should return #TRUE whenever something
1012 * valid (such as returning an error, or succeeding) occurs, and #FALSE
1013 * if it gets confused in some way.
1014 *
1015 * @param description description of the test used in verbose output
1016 * @param func function to call
1017 * @param data data to pass to function
1018 * @returns #TRUE if the function never returns FALSE
1019 */
1020 dbus_bool_t
_dbus_test_oom_handling(const char * description,DBusTestMemoryFunction func,void * data)1021 _dbus_test_oom_handling (const char *description,
1022 DBusTestMemoryFunction func,
1023 void *data)
1024 {
1025 int approx_mallocs;
1026 const char *setting;
1027 int max_failures_to_try;
1028 int i;
1029
1030 /* Run once to see about how many mallocs are involved */
1031
1032 _dbus_set_fail_alloc_counter (_DBUS_INT_MAX);
1033
1034 _dbus_verbose ("Running once to count mallocs\n");
1035
1036 if (!(* func) (data))
1037 return FALSE;
1038
1039 approx_mallocs = _DBUS_INT_MAX - _dbus_get_fail_alloc_counter ();
1040
1041 _dbus_verbose ("\n=================\n%s: about %d mallocs total\n=================\n",
1042 description, approx_mallocs);
1043
1044 setting = _dbus_getenv ("DBUS_TEST_MALLOC_FAILURES");
1045 if (setting != NULL)
1046 {
1047 DBusString str;
1048 long v;
1049 _dbus_string_init_const (&str, setting);
1050 v = 4;
1051 if (!_dbus_string_parse_int (&str, 0, &v, NULL))
1052 _dbus_warn ("couldn't parse '%s' as integer\n", setting);
1053 max_failures_to_try = v;
1054 }
1055 else
1056 {
1057 max_failures_to_try = 4;
1058 }
1059
1060 i = setting ? max_failures_to_try - 1 : 1;
1061 while (i < max_failures_to_try)
1062 {
1063 _dbus_set_fail_alloc_failures (i);
1064 if (!run_failing_each_malloc (approx_mallocs, description, func, data))
1065 return FALSE;
1066 ++i;
1067 }
1068
1069 _dbus_verbose ("\n=================\n%s: all iterations passed\n=================\n",
1070 description);
1071
1072 return TRUE;
1073 }
1074 #endif /* DBUS_BUILD_TESTS */
1075
1076 /** @} */
1077