1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22 /*
23 * Copyright (c) 1992, 2010, Oracle and/or its affiliates. All rights reserved.
24 * Copyright 2014 Garrett D'Amore <garrett@damore.org>
25 * Copyright 2016 Joyent, Inc.
26 */
27
28 /*
29 * Implementation of all external interfaces between ld.so.1 and libc.
30 *
31 * This file started as a set of routines that provided synchronization and
32 * locking operations using calls to libthread. libthread has merged with libc
33 * under the Unified Process Model (UPM), and things have gotten a lot simpler.
34 * This file continues to establish and redirect various events within ld.so.1
35 * to interfaces within libc.
36 *
37 * Until libc is loaded and relocated, any external interfaces are captured
38 * locally. Each link-map list maintains its own set of external vectors, as
39 * each link-map list typically provides its own libc. Although this per-link-
40 * map list vectoring provides a degree of flexibility, there is a protocol
41 * expected when calling various libc interfaces.
42 *
43 * i. Any new alternative link-map list should call CI_THRINIT, and then call
44 * CI_TLS_MODADD to register any TLS for each object of that link-map list
45 * (this item is labeled i. as auditors can be the first objects loaded,
46 * and they exist on their own lik-map list).
47 *
48 * ii. For the primary link-map list, CI_TLS_STATMOD must be called first to
49 * register any static TLS. This routine is called regardless of there
50 * being any TLS, as this routine also establishes the link-map list as the
51 * primary list and fixes the association of uberdata). CI_THRINIT should
52 * then be called.
53 *
54 * iii. Any objects added to an existing link-map list (primary or alternative)
55 * should call CI_TLS_MODADD to register any additional TLS.
56 *
57 * These events are established by:
58 *
59 * i. Typically, libc is loaded as part of the primary dependencies of any
60 * link-map list (since the Unified Process Model (UPM), libc can't be
61 * lazily loaded). To minimize the possibility of loading and registering
62 * objects, and then tearing them down (because of a relocation error),
63 * external vectors are established as part of load_completion(). This
64 * routine is called on completion of any operation that can cause objects
65 * to be loaded. This point of control insures the objects have been fully
66 * analyzed and relocated, and moved to their controlling link-map list.
67 * The external vectors are established prior to any .inits being fired.
68 *
69 * ii. Calls to CI_THRINIT, and CI_TLS_MODADD also occur as part of
70 * load_completion(). CI_THRINIT is only called once for each link-map
71 * control list.
72 *
73 * iii. Calls to CI_TLS_STATMOD, and CI_THRINIT occur for the primary link-map
74 * list in the final stages of setup().
75 *
76 * The interfaces provide by libc can be divided into two families. The first
77 * family consists of those interfaces that should be called from the link-map
78 * list. It's possible that these interfaces convey state concerning the
79 * link-map list they are part of:
80 *
81 * CI_ATEXIT
82 * CI TLS_MODADD
83 * CI_TLS_MODREM
84 * CI_TLS_STATMOD
85 * CI_THRINIT
86 *
87 * The second family are global in nature, that is, the link-map list from
88 * which they are called provides no state information. In fact, for
89 * CI_BIND_GUARD, the calling link-map isn't even known. The link-map can only
90 * be deduced after ld.so.1's global lock has been obtained. Therefore, the
91 * following interfaces are also maintained as global:
92 *
93 * CI_LCMESSAGES
94 * CI_BIND_GUARD
95 * CI_BIND_CLEAR
96 * CI_THR_SELF
97 *
98 * Note, it is possible that these global interfaces are obtained from an
99 * alternative link-map list that gets torn down because of a processing
100 * failure (unlikely, because the link-map list components must be analyzed
101 * and relocated prior to load_completion(), but perhaps the tear down is still
102 * a possibility). Thus the global interfaces may have to be replaced. Once
103 * the interfaces have been obtained from the primary link-map, they can
104 * remain fixed, as the primary link-map isn't going to go anywhere.
105 *
106 * The last wrinkle in the puzzle is what happens if an alternative link-map
107 * is loaded with no libc dependency? In this case, the alternative objects
108 * can not call CI_THRINIT, can not be allowed to use TLS, and will not receive
109 * any atexit processing.
110 *
111 * The history of these external interfaces is defined by their version:
112 *
113 * TI_VERSION == 1
114 * Under this model libthread provided rw_rwlock/rw_unlock, through which
115 * all rt_mutex_lock/rt_mutex_unlock calls were vectored.
116 * Under libc/libthread these interfaces provided _sigon/_sigoff (unlike
117 * lwp/libthread that provided signal blocking via bind_guard/bind_clear).
118 *
119 * TI_VERSION == 2
120 * Under this model only libthreads bind_guard/bind_clear and thr_self
121 * interfaces were used. Both libthreads blocked signals under the
122 * bind_guard/bind_clear interfaces. Lower level locking is derived
123 * from internally bound _lwp_ interfaces. This removes recursive
124 * problems encountered when obtaining locking interfaces from libthread.
125 * The use of mutexes over reader/writer locks also enables the use of
126 * condition variables for controlling thread concurrency (allows access
127 * to objects only after their .init has completed).
128 *
129 * NOTE, the TI_VERSION indicated the ti_interface version number, where the
130 * ti_interface was a large vector of functions passed to both libc (to override
131 * the thread stub interfaces) and ld.so.1. ld.so.1 used only a small subset of
132 * these interfaces.
133 *
134 * CI_VERSION == 1
135 * Introduced with CI_VERSION & CI_ATEXIT
136 *
137 * CI_VERSION == 2 (Solaris 8 update 2).
138 * Added support for CI_LCMESSAGES
139 *
140 * CI_VERSION == 3 (Solaris 9).
141 * Added the following versions to the CI table:
142 *
143 * CI_BIND_GUARD, CI_BIND_CLEAR, CI_THR_SELF
144 * CI_TLS_MODADD, CI_TLS_MOD_REMOVE, CI_TLS_STATMOD
145 *
146 * This version introduced the DT_SUNW_RTLDINFO structure as a mechanism
147 * to handshake with ld.so.1.
148 *
149 * CI_VERSION == 4 (Solaris 10).
150 * Added the CI_THRINIT handshake as part of the libc/libthread unified
151 * process model. libc now initializes the current thread pointer from
152 * this interface (and no longer relies on the INITFIRST flag - which
153 * others have started to camp out on).
154 *
155 * CI_VERSION == 5 (Solaris 11).
156 * Use of "protected" references within libc, so that symbols are
157 * pre-bound, and don't require ld.so.1 binding. This implementation
158 * protects libc's critical regions from being vectored to auditors.
159 *
160 * CI_VERSION == 6 (Solaris 11).
161 * Added the CI_CRITICAL handshake, to allow "mem*" family to be reexposed
162 * as "global", and thus be redirected to auxiliary filters.
163 *
164 * Release summary:
165 *
166 * Solaris 8 CI_ATEXIT via _ld_libc()
167 * TI_* via _ld_concurrency()
168 *
169 * Solaris 9 CI_ATEXIT and CI_LCMESSAGES via _ld_libc()
170 * CI_* via RTLDINFO and _ld_libc() - new libthread
171 * TI_* via _ld_concurrency() - old libthread
172 *
173 * Solaris 10 CI_ATEXIT and CI_LCMESSAGES via _ld_libc()
174 * CI_* via RTLDINFO and _ld_libc() - new libthread
175 */
176
177 #include <sys/debug.h>
178 #include <synch.h>
179 #include <signal.h>
180 #include <thread.h>
181 #include <synch.h>
182 #include <strings.h>
183 #include <stdio.h>
184 #include <debug.h>
185 #include <libc_int.h>
186 #include "_elf.h"
187 #include "_rtld.h"
188
189 /*
190 * This interface provides the unified process model communication between
191 * ld.so.1 and libc. This interface can be called a number of times:
192 *
193 * - Initially, this interface is called to process RTLDINFO. This data
194 * structure is typically provided by libc, and contains the address of
195 * libc interfaces that must be called to initialize threads information.
196 *
197 * - _ld_libc(), this interface can also be called by libc at process
198 * initialization, after libc has been loaded and relocated, but before
199 * control has been passed to any user code (.init's or main()). This
200 * call provides additional libc interface information that ld.so.1 must
201 * call during process execution.
202 *
203 * - _ld_libc() can also be called by libc during process execution to
204 * re-establish interfaces such as the locale.
205 */
206 static void
get_lcinterface(Rt_map * lmp,Lc_interface * funcs)207 get_lcinterface(Rt_map *lmp, Lc_interface *funcs)
208 {
209 int threaded = 0, entry = 0, tag;
210 Lm_list *lml;
211 Lc_desc *lcp;
212
213 if ((lmp == NULL) || (funcs == NULL))
214 return;
215
216 /*
217 * Once the process is active, ensure we grab a lock.
218 */
219 if (rtld_flags & RT_FL_APPLIC)
220 entry = enter(0);
221
222 lml = LIST(lmp);
223 lcp = &lml->lm_lcs[0];
224
225 DBG_CALL(Dbg_util_nl(lml, DBG_NL_STD));
226
227 for (tag = funcs->ci_tag; tag; tag = (++funcs)->ci_tag) {
228 char *gptr;
229 char *lptr = funcs->ci_un.ci_ptr;
230
231 DBG_CALL(Dbg_util_lcinterface(lmp, tag, lptr));
232
233 if (tag >= CI_MAX)
234 continue;
235
236 /*
237 * Maintain all interfaces on a per-link-map basis. Note, for
238 * most interfaces, only the first interface is used for any
239 * link-map list. This prevents accidents with developers who
240 * manage to load two different versions of libc.
241 */
242 if ((lcp[tag].lc_lmp) &&
243 (tag != CI_LCMESSAGES) && (tag != CI_VERSION)) {
244 DBG_CALL(Dbg_unused_lcinterface(lmp,
245 lcp[tag].lc_lmp, tag));
246 continue;
247 }
248
249 lcp[tag].lc_un.lc_ptr = lptr;
250 lcp[tag].lc_lmp = lmp;
251
252 gptr = glcs[tag].lc_un.lc_ptr;
253
254 /*
255 * Process any interfaces that must be maintained on a global
256 * basis.
257 */
258 switch (tag) {
259 case CI_ATEXIT:
260 break;
261
262 case CI_LCMESSAGES:
263 /*
264 * At startup, ld.so.1 can establish a locale from one
265 * of the locale family of environment variables (see
266 * ld_str_env() and readenv_user()). During process
267 * execution the locale can also be changed by the user.
268 * This interface is called from libc should the locale
269 * be modified. Presently, only one global locale is
270 * maintained for all link-map lists, and only objects
271 * on the primrary link-map may change this locale.
272 */
273 if ((lml->lm_flags & LML_FLG_BASELM) &&
274 ((gptr == NULL) || (strcmp(gptr, lptr) != 0))) {
275 /*
276 * If we've obtained a message locale (typically
277 * supplied via libc's setlocale()), then
278 * register the locale for use in dgettext() so
279 * as to reestablish the locale for ld.so.1's
280 * messages.
281 */
282 if (gptr) {
283 free((void *)gptr);
284 rtld_flags |= RT_FL_NEWLOCALE;
285 }
286 glcs[tag].lc_un.lc_ptr = strdup(lptr);
287
288 /*
289 * Clear any cached messages.
290 */
291 bzero(err_strs, sizeof (err_strs));
292 nosym_str = NULL;
293 }
294 break;
295
296 case CI_BIND_GUARD:
297 case CI_BIND_CLEAR:
298 case CI_THR_SELF:
299 case CI_CRITICAL:
300 /*
301 * If the global vector is unset, or this is the primary
302 * link-map, set the global vector.
303 */
304 if ((gptr == NULL) || (lml->lm_flags & LML_FLG_BASELM))
305 glcs[tag].lc_un.lc_ptr = lptr;
306
307 /* FALLTHROUGH */
308
309 case CI_TLS_MODADD:
310 case CI_TLS_MODREM:
311 case CI_TLS_STATMOD:
312 case CI_THRINIT:
313 threaded++;
314 break;
315
316 case CI_VERSION:
317 if ((rtld_flags2 & RT_FL2_RTLDSEEN) == 0) {
318 Aliste idx;
319 Lm_list *lml2;
320 int version;
321
322 rtld_flags2 |= RT_FL2_RTLDSEEN;
323
324 version = funcs->ci_un.ci_val;
325 #if defined(CI_V_FIVE)
326 if (version >= CI_V_FIVE) {
327 thr_flg_nolock = THR_FLG_NOLOCK;
328 thr_flg_reenter = THR_FLG_REENTER;
329 }
330 #endif
331 if (version < CI_V_FOUR)
332 break;
333
334 rtld_flags2 |= RT_FL2_UNIFPROC;
335
336 /*
337 * We might have seen an auditor which is not
338 * dependent on libc. Such an auditor's link
339 * map list has LML_FLG_HOLDLOCK set. This
340 * lock needs to be dropped. Refer to
341 * audit_setup() in audit.c.
342 */
343 if ((rtld_flags2 & RT_FL2_HASAUDIT) == 0)
344 break;
345
346 /*
347 * Yes, we did. Take care of them.
348 */
349 for (APLIST_TRAVERSE(dynlm_list, idx, lml2)) {
350 Rt_map *map = (Rt_map *)lml2->lm_head;
351
352 if (FLAGS(map) & FLG_RT_AUDIT) {
353 lml2->lm_flags &=
354 ~LML_FLG_HOLDLOCK;
355 }
356 }
357 }
358 break;
359
360 default:
361 break;
362 }
363 }
364
365 if (threaded) {
366 /*
367 * If a version of libc gives us only a subset of the TLS
368 * interfaces, it's confused and we discard the whole lot.
369 */
370 if ((lcp[CI_TLS_MODADD].lc_un.lc_func &&
371 lcp[CI_TLS_MODREM].lc_un.lc_func &&
372 lcp[CI_TLS_STATMOD].lc_un.lc_func) == NULL) {
373 lcp[CI_TLS_MODADD].lc_un.lc_func = NULL;
374 lcp[CI_TLS_MODREM].lc_un.lc_func = NULL;
375 lcp[CI_TLS_STATMOD].lc_un.lc_func = NULL;
376 }
377
378 /*
379 * Indicate that we're now thread capable.
380 */
381 if ((lml->lm_flags & LML_FLG_RTLDLM) == 0)
382 rtld_flags |= RT_FL_THREADS;
383 }
384
385 if (entry)
386 leave(lml, 0);
387 }
388
389 /*
390 * At this point we know we have a set of objects that have been fully analyzed
391 * and relocated. Prior to the next major step of running .init sections (ie.
392 * running user code), retrieve any RTLDINFO interfaces.
393 */
394 int
rt_get_extern(Lm_list * lml,Rt_map * lmp)395 rt_get_extern(Lm_list *lml, Rt_map *lmp)
396 {
397 if (lml->lm_rti) {
398 Aliste idx;
399 Rti_desc *rti;
400
401 for (ALIST_TRAVERSE(lml->lm_rti, idx, rti))
402 get_lcinterface(rti->rti_lmp, rti->rti_info);
403
404 free(lml->lm_rti);
405 lml->lm_rti = 0;
406 }
407
408 /*
409 * Perform some sanity checks. If we have TLS requirements we better
410 * have the associated external interfaces.
411 */
412 if (lml->lm_tls &&
413 (lml->lm_lcs[CI_TLS_STATMOD].lc_un.lc_func == NULL)) {
414 eprintf(lml, ERR_FATAL, MSG_INTL(MSG_TLS_NOSUPPORT),
415 NAME(lmp));
416 return (0);
417 }
418 return (1);
419 }
420
421 /*
422 * Provide an interface for libc to communicate additional interface
423 * information.
424 */
425 void
_ld_libc(void * ptr)426 _ld_libc(void *ptr)
427 {
428 get_lcinterface(_caller(caller(), CL_EXECDEF), (Lc_interface *)ptr);
429 }
430
431 static int bindmask = 0;
432
433 int
rt_bind_guard(int flags)434 rt_bind_guard(int flags)
435 {
436 int (*fptr)(int);
437 int bindflag;
438
439 if ((fptr = glcs[CI_BIND_GUARD].lc_un.lc_func) != NULL) {
440 return ((*fptr)(flags));
441 } else {
442 bindflag = (flags & THR_FLG_RTLD);
443 if ((bindflag & bindmask) == 0) {
444 bindmask |= bindflag;
445 return (1);
446 }
447 return (0);
448 }
449 }
450
451 int
rt_bind_clear(int flags)452 rt_bind_clear(int flags)
453 {
454 int (*fptr)(int);
455 int bindflag;
456
457 if ((fptr = glcs[CI_BIND_CLEAR].lc_un.lc_func) != NULL) {
458 return ((*fptr)(flags));
459 } else {
460 bindflag = (flags & THR_FLG_RTLD);
461 if (bindflag == 0)
462 return (bindmask);
463 else {
464 bindmask &= ~bindflag;
465 return (0);
466 }
467 }
468 }
469
470 /*
471 * Make sure threads have been initialized. This interface is called once for
472 * each link-map list.
473 */
474 void
rt_thr_init(Lm_list * lml)475 rt_thr_init(Lm_list *lml)
476 {
477 void (*fptr)(void);
478
479 if ((fptr =
480 (void (*)())lml->lm_lcs[CI_THRINIT].lc_un.lc_func) != NULL) {
481 lml->lm_lcs[CI_THRINIT].lc_un.lc_func = NULL;
482
483 leave(lml, thr_flg_reenter);
484 (*fptr)();
485 (void) enter(thr_flg_reenter);
486
487 /*
488 * If this is an alternative link-map list, and this is the
489 * first call to initialize threads, don't let the destination
490 * libc be deleted. It is possible that an auditors complete
491 * initialization fails, but there is presently no main link-map
492 * list. As this libc has established the thread pointer, don't
493 * delete this libc, otherwise the initialization of libc on the
494 * main link-map can be compromised during its threads
495 * initialization.
496 */
497 if (((lml->lm_flags & LML_FLG_BASELM) == 0) &&
498 ((rtld_flags2 & RT_FL2_PLMSETUP) == 0))
499 MODE(lml->lm_lcs[CI_THRINIT].lc_lmp) |= RTLD_NODELETE;
500 }
501 }
502
503 thread_t
rt_thr_self()504 rt_thr_self()
505 {
506 thread_t (*fptr)(void);
507
508 if ((fptr = (thread_t (*)())glcs[CI_THR_SELF].lc_un.lc_func) != NULL)
509 return ((*fptr)());
510
511 return (1);
512 }
513
514 int
rt_mutex_lock(Rt_lock * mp)515 rt_mutex_lock(Rt_lock *mp)
516 {
517 return (_lwp_mutex_lock((lwp_mutex_t *)mp));
518 }
519
520 int
rt_mutex_unlock(Rt_lock * mp)521 rt_mutex_unlock(Rt_lock *mp)
522 {
523 return (_lwp_mutex_unlock((lwp_mutex_t *)mp));
524 }
525
526 /*
527 * Test whether we're in a libc critical region. Certain function references,
528 * like the "mem*" family, might require binding. Although these functions can
529 * safely bind to auxiliary filtees, they should not be captured by auditors.
530 */
531 int
rt_critical()532 rt_critical()
533 {
534 int (*fptr)(void);
535
536 if ((fptr = glcs[CI_CRITICAL].lc_un.lc_func) != NULL)
537 return ((*fptr)());
538
539 return (0);
540 }
541
542 /*
543 * Mutex interfaces to resolve references from any objects extracted from
544 * libc_pic.a. Note, as ld.so.1 is essentially single threaded these can be
545 * noops.
546 */
547 #pragma weak lmutex_lock = mutex_lock
548 /* ARGSUSED */
549 int
mutex_lock(mutex_t * mp)550 mutex_lock(mutex_t *mp)
551 {
552 return (0);
553 }
554
555 #pragma weak lmutex_unlock = mutex_unlock
556 /* ARGSUSED */
557 int
mutex_unlock(mutex_t * mp)558 mutex_unlock(mutex_t *mp)
559 {
560 return (0);
561 }
562
563 /* ARGSUSED */
564 int
mutex_init(mutex_t * mp,int type,void * arg)565 mutex_init(mutex_t *mp, int type, void *arg)
566 {
567 return (0);
568 }
569
570 /* ARGSUSED */
571 int
mutex_destroy(mutex_t * mp)572 mutex_destroy(mutex_t *mp)
573 {
574 return (0);
575 }
576
577 /*
578 * This is needed to satisfy sysconf() (case _SC_THREAD_STACK_MIN)
579 */
580 size_t
thr_min_stack()581 thr_min_stack()
582 {
583 return (sizeof (uintptr_t) * 1024);
584 }
585
586 /*
587 * Local str[n]casecmp() interfaces for the dynamic linker,
588 * to avoid problems when linking with libc_pic.a
589 */
590 int
strcasecmp(const char * s1,const char * s2)591 strcasecmp(const char *s1, const char *s2)
592 {
593 extern int ascii_strcasecmp(const char *, const char *);
594
595 return (ascii_strcasecmp(s1, s2));
596 }
597
598 int
strncasecmp(const char * s1,const char * s2,size_t n)599 strncasecmp(const char *s1, const char *s2, size_t n)
600 {
601 extern int ascii_strncasecmp(const char *, const char *, size_t);
602
603 return (ascii_strncasecmp(s1, s2, n));
604 }
605
606 /*
607 * The following functions are cancellation points in libc.
608 * They are called from other functions in libc that we extract
609 * and use directly. We don't do cancellation while we are in
610 * the dynamic linker, so we redefine these to call the primitive,
611 * non-cancellation interfaces.
612 */
613 int
close(int fildes)614 close(int fildes)
615 {
616 extern int __close(int);
617
618 return (__close(fildes));
619 }
620
621 int
fcntl(int fildes,int cmd,...)622 fcntl(int fildes, int cmd, ...)
623 {
624 extern int __fcntl(int, int, ...);
625 intptr_t arg;
626 va_list ap;
627
628 va_start(ap, cmd);
629 arg = va_arg(ap, intptr_t);
630 va_end(ap);
631 return (__fcntl(fildes, cmd, arg));
632 }
633
634 int
open(const char * path,int oflag,...)635 open(const char *path, int oflag, ...)
636 {
637 extern int __open(const char *, int, mode_t);
638 mode_t mode;
639 va_list ap;
640
641 va_start(ap, oflag);
642 mode = va_arg(ap, mode_t);
643 va_end(ap);
644 return (__open(path, oflag, mode));
645 }
646
647 int
openat(int fd,const char * path,int oflag,...)648 openat(int fd, const char *path, int oflag, ...)
649 {
650 extern int __openat(int, const char *, int, mode_t);
651 mode_t mode;
652 va_list ap;
653
654 va_start(ap, oflag);
655 mode = va_arg(ap, mode_t);
656 va_end(ap);
657 return (__openat(fd, path, oflag, mode));
658 }
659
660 ssize_t
read(int fd,void * buf,size_t size)661 read(int fd, void *buf, size_t size)
662 {
663 extern ssize_t __read(int, void *, size_t);
664 return (__read(fd, buf, size));
665 }
666
667 ssize_t
write(int fd,const void * buf,size_t size)668 write(int fd, const void *buf, size_t size)
669 {
670 extern ssize_t __write(int, const void *, size_t);
671 return (__write(fd, buf, size));
672 }
673
674 /*
675 * ASCII versions of ctype character classification functions. This avoids
676 * pulling in the entire locale framework that is in libc.
677 */
678
679 int
isdigit(int c)680 isdigit(int c)
681 {
682 return ((c >= '0' && c <= '9') ? 1 : 0);
683 }
684
685 int
isupper(int c)686 isupper(int c)
687 {
688 return ((c >= 'A' && c <= 'Z') ? 1 : 0);
689 }
690
691 int
islower(int c)692 islower(int c)
693 {
694 return ((c >= 'a' && c <= 'z') ? 1 : 0);
695 }
696
697 int
isspace(int c)698 isspace(int c)
699 {
700 return (((c == ' ') || (c == '\t') || (c == '\r') || (c == '\n') ||
701 (c == '\v') || (c == '\f')) ? 1 : 0);
702 }
703
704 int
isxdigit(int c)705 isxdigit(int c)
706 {
707 return ((isdigit(c) || (c >= 'A' && c <= 'F') ||
708 (c >= 'a' && c <= 'f')) ? 1 : 0);
709 }
710
711 int
isalpha(int c)712 isalpha(int c)
713 {
714 return ((isupper(c) || islower(c)) ? 1 : 0);
715 }
716
717 int
isalnum(int c)718 isalnum(int c)
719 {
720 return ((isalpha(c) || isdigit(c)) ? 1 : 0);
721 }
722
723 #if defined(__i386) || defined(__amd64)
724 /*
725 * Instead of utilizing the comm page for clock_gettime, rtld uses the raw
726 * syscall instead. Doing so decreases the surface of symbols needed from libc
727 * for a modest performance cost.
728 */
729 extern int __clock_gettime_sys(clockid_t, struct timespec *);
730
731 int
__clock_gettime(clockid_t clock_id,struct timespec * tp)732 __clock_gettime(clockid_t clock_id, struct timespec *tp)
733 {
734 return (__clock_gettime_sys(clock_id, tp));
735 }
736 #endif /* defined(__i386) || defined(__amd64) */
737