1 /*
2  * Copyright (c) 1991, 1992 Paul Kranenburg <pk@cs.few.eur.nl>
3  * Copyright (c) 1993 Branko Lankester <branko@hacktic.nl>
4  * Copyright (c) 1993, 1994, 1995, 1996 Rick Sladkey <jrs@world.std.com>
5  * Copyright (c) 1996-1999 Wichert Akkerman <wichert@cistron.nl>
6  * Copyright (c) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
7  *                     Linux for s390 port by D.J. Barrow
8  *                    <barrow_dj@mail.yahoo.com,djbarrow@de.ibm.com>
9  * All rights reserved.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. The name of the author may not be used to endorse or promote products
20  *    derived from this software without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include "defs.h"
35 #include <signal.h>
36 
37 #ifndef NSIG
38 # warning NSIG is not defined, using 32
39 # define NSIG 32
40 #elif NSIG < 32
41 # error NSIG < 32
42 #endif
43 
44 /* The libc headers do not define this constant since it should only be
45    used by the implementation.  So we define it here.  */
46 #ifndef SA_RESTORER
47 # ifdef ASM_SA_RESTORER
48 #  define SA_RESTORER ASM_SA_RESTORER
49 # endif
50 #endif
51 
52 /*
53  * Some architectures define SA_RESTORER in their headers,
54  * but do not actually have sa_restorer.
55  *
56  * Some architectures, otherwise, do not define SA_RESTORER in their headers,
57  * but actually have sa_restorer.
58  */
59 #ifdef SA_RESTORER
60 # if defined HPPA || defined IA64
61 #  define HAVE_SA_RESTORER 0
62 # else
63 #  define HAVE_SA_RESTORER 1
64 # endif
65 #else /* !SA_RESTORER */
66 # if defined SPARC || defined SPARC64 || defined M68K
67 #  define HAVE_SA_RESTORER 1
68 # else
69 #  define HAVE_SA_RESTORER 0
70 # endif
71 #endif
72 
73 #include "xlat/sigact_flags.h"
74 #include "xlat/sigprocmaskcmds.h"
75 
76 /* Anonymous realtime signals. */
77 #ifndef ASM_SIGRTMIN
78 /* Linux kernel >= 3.18 defines SIGRTMIN to 32 on all architectures. */
79 # define ASM_SIGRTMIN 32
80 #endif
81 #ifndef ASM_SIGRTMAX
82 /* Under glibc 2.1, SIGRTMAX et al are functions, but __SIGRTMAX is a
83    constant.  This is what we want.  Otherwise, just use SIGRTMAX. */
84 # ifdef SIGRTMAX
85 #  ifndef __SIGRTMAX
86 #   define __SIGRTMAX SIGRTMAX
87 #  endif
88 # endif
89 # ifdef __SIGRTMAX
90 #  define ASM_SIGRTMAX __SIGRTMAX
91 # endif
92 #endif
93 
94 /* Note on the size of sigset_t:
95  *
96  * In glibc, sigset_t is an array with space for 1024 bits (!),
97  * even though all arches supported by Linux have only 64 signals
98  * except MIPS, which has 128. IOW, it is 128 bytes long.
99  *
100  * In-kernel sigset_t is sized correctly (it is either 64 or 128 bit long).
101  * However, some old syscall return only 32 lower bits (one word).
102  * Example: sys_sigpending vs sys_rt_sigpending.
103  *
104  * Be aware of this fact when you try to
105  *     memcpy(&tcp->u_arg[1], &something, sizeof(sigset_t))
106  * - sizeof(sigset_t) is much bigger than you think,
107  * it may overflow tcp->u_arg[] array, and it may try to copy more data
108  * than is really available in <something>.
109  * Similarly,
110  *     umoven(tcp, addr, sizeof(sigset_t), &sigset)
111  * may be a bad idea: it'll try to read much more data than needed
112  * to fetch a sigset_t.
113  * Use (NSIG / 8) as a size instead.
114  */
115 
116 const char *
signame(const int sig)117 signame(const int sig)
118 {
119 	static char buf[sizeof("SIGRT_%u") + sizeof(int)*3];
120 
121 	if (sig >= 0) {
122 		const unsigned int s = sig;
123 
124 		if (s < nsignals)
125 			return signalent[s];
126 #ifdef ASM_SIGRTMAX
127 		if (s >= ASM_SIGRTMIN && s <= ASM_SIGRTMAX) {
128 			sprintf(buf, "SIGRT_%u", s - ASM_SIGRTMIN);
129 			return buf;
130 		}
131 #endif
132 	}
133 	sprintf(buf, "%d", sig);
134 	return buf;
135 }
136 
137 static unsigned int
popcount32(const uint32_t * a,unsigned int size)138 popcount32(const uint32_t *a, unsigned int size)
139 {
140 	unsigned int count = 0;
141 
142 	for (; size; ++a, --size) {
143 		uint32_t x = *a;
144 
145 #ifdef HAVE___BUILTIN_POPCOUNT
146 		count += __builtin_popcount(x);
147 #else
148 		for (; x; ++count)
149 			x &= x - 1;
150 #endif
151 	}
152 
153 	return count;
154 }
155 
156 const char *
sprintsigmask_n(const char * prefix,const void * sig_mask,unsigned int bytes)157 sprintsigmask_n(const char *prefix, const void *sig_mask, unsigned int bytes)
158 {
159 	/*
160 	 * The maximum number of signal names to be printed is NSIG * 2 / 3.
161 	 * Most of signal names have length 7,
162 	 * average length of signal names is less than 7.
163 	 * The length of prefix string does not exceed 16.
164 	 */
165 	static char outstr[128 + 8 * (NSIG * 2 / 3)];
166 
167 	char *s;
168 	const uint32_t *mask;
169 	uint32_t inverted_mask[NSIG / 32];
170 	unsigned int size;
171 	int i;
172 	char sep;
173 
174 	s = stpcpy(outstr, prefix);
175 
176 	mask = sig_mask;
177 	/* length of signal mask in 4-byte words */
178 	size = (bytes >= NSIG / 8) ? NSIG / 32 : (bytes + 3) / 4;
179 
180 	/* check whether 2/3 or more bits are set */
181 	if (popcount32(mask, size) >= size * 32 * 2 / 3) {
182 		/* show those signals that are NOT in the mask */
183 		unsigned int j;
184 		for (j = 0; j < size; ++j)
185 			inverted_mask[j] = ~mask[j];
186 		mask = inverted_mask;
187 		*s++ = '~';
188 	}
189 
190 	sep = '[';
191 	for (i = 0; (i = next_set_bit(mask, i, size * 32)) >= 0; ) {
192 		++i;
193 		*s++ = sep;
194 		if ((unsigned) i < nsignals) {
195 			s = stpcpy(s, signalent[i] + 3);
196 		}
197 #ifdef ASM_SIGRTMAX
198 		else if (i >= ASM_SIGRTMIN && i <= ASM_SIGRTMAX) {
199 			s += sprintf(s, "RT_%u", i - ASM_SIGRTMIN);
200 		}
201 #endif
202 		else {
203 			s += sprintf(s, "%u", i);
204 		}
205 		sep = ' ';
206 	}
207 	if (sep == '[')
208 		*s++ = sep;
209 	*s++ = ']';
210 	*s = '\0';
211 	return outstr;
212 }
213 
214 #define sprintsigmask_val(prefix, mask) \
215 	sprintsigmask_n((prefix), &(mask), sizeof(mask))
216 
217 #define tprintsigmask_val(prefix, mask) \
218 	tprints(sprintsigmask_n((prefix), &(mask), sizeof(mask)))
219 
220 void
printsignal(int nr)221 printsignal(int nr)
222 {
223 	tprints(signame(nr));
224 }
225 
226 void
print_sigset_addr_len(struct tcb * tcp,long addr,long len)227 print_sigset_addr_len(struct tcb *tcp, long addr, long len)
228 {
229 	char mask[NSIG / 8];
230 
231 	/* Here len is usually equals NSIG / 8 or current_wordsize.
232 	 * But we code this defensively:
233 	 */
234 	if (len < 0) {
235 		printaddr(addr);
236 		return;
237 	}
238 	if (len >= NSIG / 8)
239 		len = NSIG / 8;
240 	else
241 		len = (len + 3) & ~3;
242 
243 	if (umoven_or_printaddr(tcp, addr, len, mask))
244 		return;
245 	tprints(sprintsigmask_n("", mask, len));
246 }
247 
SYS_FUNC(sigsetmask)248 SYS_FUNC(sigsetmask)
249 {
250 	if (entering(tcp)) {
251 		tprintsigmask_val("", tcp->u_arg[0]);
252 	}
253 	else if (!syserror(tcp)) {
254 		tcp->auxstr = sprintsigmask_val("old mask ", tcp->u_rval);
255 		return RVAL_HEX | RVAL_STR;
256 	}
257 	return 0;
258 }
259 
260 #ifdef HAVE_SIGACTION
261 
262 struct old_sigaction {
263 	/* sa_handler may be a libc #define, need to use other name: */
264 #ifdef MIPS
265 	unsigned int sa_flags;
266 	void (*__sa_handler)(int);
267 	/* Kernel treats sa_mask as an array of longs. */
268 	unsigned long sa_mask[NSIG / sizeof(long) ? NSIG / sizeof(long) : 1];
269 #else
270 	void (*__sa_handler)(int);
271 	unsigned long sa_mask;
272 	unsigned long sa_flags;
273 #endif /* !MIPS */
274 #if HAVE_SA_RESTORER
275 	void (*sa_restorer)(void);
276 #endif
277 };
278 
279 struct old_sigaction32 {
280 	/* sa_handler may be a libc #define, need to use other name: */
281 	uint32_t __sa_handler;
282 	uint32_t sa_mask;
283 	uint32_t sa_flags;
284 #if HAVE_SA_RESTORER
285 	uint32_t sa_restorer;
286 #endif
287 };
288 
289 static void
decode_old_sigaction(struct tcb * tcp,long addr)290 decode_old_sigaction(struct tcb *tcp, long addr)
291 {
292 	struct old_sigaction sa;
293 
294 #if SUPPORTED_PERSONALITIES > 1 && SIZEOF_LONG > 4
295 	if (current_wordsize != sizeof(sa.__sa_handler) && current_wordsize == 4) {
296 		struct old_sigaction32 sa32;
297 
298 		if (umove_or_printaddr(tcp, addr, &sa32))
299 			return;
300 
301 		memset(&sa, 0, sizeof(sa));
302 		sa.__sa_handler = (void*)(uintptr_t)sa32.__sa_handler;
303 		sa.sa_flags = sa32.sa_flags;
304 #if HAVE_SA_RESTORER && defined SA_RESTORER
305 		sa.sa_restorer = (void*)(uintptr_t)sa32.sa_restorer;
306 #endif
307 		sa.sa_mask = sa32.sa_mask;
308 	} else
309 #endif
310 	if (umove_or_printaddr(tcp, addr, &sa))
311 		return;
312 
313 	/* Architectures using function pointers, like
314 	 * hppa, may need to manipulate the function pointer
315 	 * to compute the result of a comparison. However,
316 	 * the __sa_handler function pointer exists only in
317 	 * the address space of the traced process, and can't
318 	 * be manipulated by strace. In order to prevent the
319 	 * compiler from generating code to manipulate
320 	 * __sa_handler we cast the function pointers to long. */
321 	tprints("{");
322 	if ((long)sa.__sa_handler == (long)SIG_ERR)
323 		tprints("SIG_ERR");
324 	else if ((long)sa.__sa_handler == (long)SIG_DFL)
325 		tprints("SIG_DFL");
326 	else if ((long)sa.__sa_handler == (long)SIG_IGN)
327 		tprints("SIG_IGN");
328 	else
329 		printaddr((long) sa.__sa_handler);
330 	tprints(", ");
331 #ifdef MIPS
332 	tprintsigmask_addr("", sa.sa_mask);
333 #else
334 	tprintsigmask_val("", sa.sa_mask);
335 #endif
336 	tprints(", ");
337 	printflags(sigact_flags, sa.sa_flags, "SA_???");
338 #if HAVE_SA_RESTORER && defined SA_RESTORER
339 	if (sa.sa_flags & SA_RESTORER)
340 		tprintf(", %p", sa.sa_restorer);
341 #endif
342 	tprints("}");
343 }
344 
SYS_FUNC(sigaction)345 SYS_FUNC(sigaction)
346 {
347 	if (entering(tcp)) {
348 		printsignal(tcp->u_arg[0]);
349 		tprints(", ");
350 		decode_old_sigaction(tcp, tcp->u_arg[1]);
351 		tprints(", ");
352 	} else
353 		decode_old_sigaction(tcp, tcp->u_arg[2]);
354 	return 0;
355 }
356 
SYS_FUNC(signal)357 SYS_FUNC(signal)
358 {
359 	if (entering(tcp)) {
360 		printsignal(tcp->u_arg[0]);
361 		tprints(", ");
362 		switch (tcp->u_arg[1]) {
363 		case (long) SIG_ERR:
364 			tprints("SIG_ERR");
365 			break;
366 		case (long) SIG_DFL:
367 			tprints("SIG_DFL");
368 			break;
369 		case (long) SIG_IGN:
370 			tprints("SIG_IGN");
371 			break;
372 		default:
373 			printaddr(tcp->u_arg[1]);
374 		}
375 		return 0;
376 	}
377 	else if (!syserror(tcp)) {
378 		switch (tcp->u_rval) {
379 		case (long) SIG_ERR:
380 			tcp->auxstr = "SIG_ERR"; break;
381 		case (long) SIG_DFL:
382 			tcp->auxstr = "SIG_DFL"; break;
383 		case (long) SIG_IGN:
384 			tcp->auxstr = "SIG_IGN"; break;
385 		default:
386 			tcp->auxstr = NULL;
387 		}
388 		return RVAL_HEX | RVAL_STR;
389 	}
390 	return 0;
391 }
392 
393 #endif /* HAVE_SIGACTION */
394 
SYS_FUNC(siggetmask)395 SYS_FUNC(siggetmask)
396 {
397 	if (exiting(tcp)) {
398 		tcp->auxstr = sprintsigmask_val("mask ", tcp->u_rval);
399 	}
400 	return RVAL_HEX | RVAL_STR;
401 }
402 
SYS_FUNC(sigsuspend)403 SYS_FUNC(sigsuspend)
404 {
405 	tprintsigmask_val("", tcp->u_arg[2]);
406 
407 	return RVAL_DECODED;
408 }
409 
410 #ifdef HAVE_SIGACTION
411 
412 /* "Old" sigprocmask, which operates with word-sized signal masks */
SYS_FUNC(sigprocmask)413 SYS_FUNC(sigprocmask)
414 {
415 # ifdef ALPHA
416 	if (entering(tcp)) {
417 		/*
418 		 * Alpha/OSF is different: it doesn't pass in two pointers,
419 		 * but rather passes in the new bitmask as an argument and
420 		 * then returns the old bitmask.  This "works" because we
421 		 * only have 64 signals to worry about.  If you want more,
422 		 * use of the rt_sigprocmask syscall is required.
423 		 * Alpha:
424 		 *	old = osf_sigprocmask(how, new);
425 		 * Everyone else:
426 		 *	ret = sigprocmask(how, &new, &old, ...);
427 		 */
428 		printxval(sigprocmaskcmds, tcp->u_arg[0], "SIG_???");
429 		tprintsigmask_val(", ", tcp->u_arg[1]);
430 	}
431 	else if (!syserror(tcp)) {
432 		tcp->auxstr = sprintsigmask_val("old mask ", tcp->u_rval);
433 		return RVAL_HEX | RVAL_STR;
434 	}
435 # else /* !ALPHA */
436 	if (entering(tcp)) {
437 		printxval(sigprocmaskcmds, tcp->u_arg[0], "SIG_???");
438 		tprints(", ");
439 		print_sigset_addr_len(tcp, tcp->u_arg[1], current_wordsize);
440 		tprints(", ");
441 	}
442 	else {
443 		print_sigset_addr_len(tcp, tcp->u_arg[2], current_wordsize);
444 	}
445 # endif /* !ALPHA */
446 	return 0;
447 }
448 
449 #endif /* HAVE_SIGACTION */
450 
SYS_FUNC(kill)451 SYS_FUNC(kill)
452 {
453 	tprintf("%ld, %s",
454 		widen_to_long(tcp->u_arg[0]),
455 		signame(tcp->u_arg[1]));
456 
457 	return RVAL_DECODED;
458 }
459 
SYS_FUNC(tgkill)460 SYS_FUNC(tgkill)
461 {
462 	tprintf("%ld, %ld, %s",
463 		widen_to_long(tcp->u_arg[0]),
464 		widen_to_long(tcp->u_arg[1]),
465 		signame(tcp->u_arg[2]));
466 
467 	return RVAL_DECODED;
468 }
469 
SYS_FUNC(sigpending)470 SYS_FUNC(sigpending)
471 {
472 	if (exiting(tcp))
473 		print_sigset_addr_len(tcp, tcp->u_arg[0], current_wordsize);
474 	return 0;
475 }
476 
SYS_FUNC(rt_sigprocmask)477 SYS_FUNC(rt_sigprocmask)
478 {
479 	/* Note: arg[3] is the length of the sigset. Kernel requires NSIG / 8 */
480 	if (entering(tcp)) {
481 		printxval(sigprocmaskcmds, tcp->u_arg[0], "SIG_???");
482 		tprints(", ");
483 		print_sigset_addr_len(tcp, tcp->u_arg[1], tcp->u_arg[3]);
484 		tprints(", ");
485 	}
486 	else {
487 		print_sigset_addr_len(tcp, tcp->u_arg[2], tcp->u_arg[3]);
488 		tprintf(", %lu", tcp->u_arg[3]);
489 	}
490 	return 0;
491 }
492 
493 /* Structure describing the action to be taken when a signal arrives.  */
494 struct new_sigaction
495 {
496 	/* sa_handler may be a libc #define, need to use other name: */
497 #ifdef MIPS
498 	unsigned int sa_flags;
499 	void (*__sa_handler)(int);
500 #else
501 	void (*__sa_handler)(int);
502 	unsigned long sa_flags;
503 #endif /* !MIPS */
504 #if HAVE_SA_RESTORER
505 	void (*sa_restorer)(void);
506 #endif
507 	/* Kernel treats sa_mask as an array of longs. */
508 	unsigned long sa_mask[NSIG / sizeof(long) ? NSIG / sizeof(long) : 1];
509 };
510 /* Same for i386-on-x86_64 and similar cases */
511 struct new_sigaction32
512 {
513 	uint32_t __sa_handler;
514 	uint32_t sa_flags;
515 #if HAVE_SA_RESTORER
516 	uint32_t sa_restorer;
517 #endif
518 	uint32_t sa_mask[2 * (NSIG / sizeof(long) ? NSIG / sizeof(long) : 1)];
519 };
520 
521 static void
decode_new_sigaction(struct tcb * tcp,long addr)522 decode_new_sigaction(struct tcb *tcp, long addr)
523 {
524 	struct new_sigaction sa;
525 
526 #if SUPPORTED_PERSONALITIES > 1 && SIZEOF_LONG > 4
527 	if (current_wordsize != sizeof(sa.sa_flags) && current_wordsize == 4) {
528 		struct new_sigaction32 sa32;
529 
530 		if (umove_or_printaddr(tcp, addr, &sa32))
531 			return;
532 
533 		memset(&sa, 0, sizeof(sa));
534 		sa.__sa_handler = (void*)(unsigned long)sa32.__sa_handler;
535 		sa.sa_flags     = sa32.sa_flags;
536 #if HAVE_SA_RESTORER && defined SA_RESTORER
537 		sa.sa_restorer  = (void*)(unsigned long)sa32.sa_restorer;
538 #endif
539 		/* Kernel treats sa_mask as an array of longs.
540 		 * For 32-bit process, "long" is uint32_t, thus, for example,
541 		 * 32th bit in sa_mask will end up as bit 0 in sa_mask[1].
542 		 * But for (64-bit) kernel, 32th bit in sa_mask is
543 		 * 32th bit in 0th (64-bit) long!
544 		 * For little-endian, it's the same.
545 		 * For big-endian, we swap 32-bit words.
546 		 */
547 		sa.sa_mask[0] = sa32.sa_mask[0] + ((long)(sa32.sa_mask[1]) << 32);
548 	} else
549 #endif
550 	if (umove_or_printaddr(tcp, addr, &sa))
551 		return;
552 
553 	/* Architectures using function pointers, like
554 	 * hppa, may need to manipulate the function pointer
555 	 * to compute the result of a comparison. However,
556 	 * the __sa_handler function pointer exists only in
557 	 * the address space of the traced process, and can't
558 	 * be manipulated by strace. In order to prevent the
559 	 * compiler from generating code to manipulate
560 	 * __sa_handler we cast the function pointers to long. */
561 	if ((long)sa.__sa_handler == (long)SIG_ERR)
562 		tprints("{SIG_ERR, ");
563 	else if ((long)sa.__sa_handler == (long)SIG_DFL)
564 		tprints("{SIG_DFL, ");
565 	else if ((long)sa.__sa_handler == (long)SIG_IGN)
566 		tprints("{SIG_IGN, ");
567 	else
568 		tprintf("{%#lx, ", (long) sa.__sa_handler);
569 	/*
570 	 * Sigset size is in tcp->u_arg[4] (SPARC)
571 	 * or in tcp->u_arg[3] (all other),
572 	 * but kernel won't handle sys_rt_sigaction
573 	 * with wrong sigset size (just returns EINVAL instead).
574 	 * We just fetch the right size, which is NSIG / 8.
575 	 */
576 	tprintsigmask_val("", sa.sa_mask);
577 	tprints(", ");
578 
579 	printflags(sigact_flags, sa.sa_flags, "SA_???");
580 #if HAVE_SA_RESTORER && defined SA_RESTORER
581 	if (sa.sa_flags & SA_RESTORER)
582 		tprintf(", %p", sa.sa_restorer);
583 #endif
584 	tprints("}");
585 }
586 
SYS_FUNC(rt_sigaction)587 SYS_FUNC(rt_sigaction)
588 {
589 	if (entering(tcp)) {
590 		printsignal(tcp->u_arg[0]);
591 		tprints(", ");
592 		decode_new_sigaction(tcp, tcp->u_arg[1]);
593 		tprints(", ");
594 	} else {
595 		decode_new_sigaction(tcp, tcp->u_arg[2]);
596 #if defined(SPARC) || defined(SPARC64)
597 		tprintf(", %#lx, %lu", tcp->u_arg[3], tcp->u_arg[4]);
598 #elif defined(ALPHA)
599 		tprintf(", %lu, %#lx", tcp->u_arg[3], tcp->u_arg[4]);
600 #else
601 		tprintf(", %lu", tcp->u_arg[3]);
602 #endif
603 	}
604 	return 0;
605 }
606 
SYS_FUNC(rt_sigpending)607 SYS_FUNC(rt_sigpending)
608 {
609 	if (exiting(tcp)) {
610 		/*
611 		 * One of the few syscalls where sigset size (arg[1])
612 		 * is allowed to be <= NSIG / 8, not strictly ==.
613 		 * This allows non-rt sigpending() syscall
614 		 * to reuse rt_sigpending() code in kernel.
615 		 */
616 		print_sigset_addr_len(tcp, tcp->u_arg[0], tcp->u_arg[1]);
617 		tprintf(", %lu", tcp->u_arg[1]);
618 	}
619 	return 0;
620 }
621 
SYS_FUNC(rt_sigsuspend)622 SYS_FUNC(rt_sigsuspend)
623 {
624 	/* NB: kernel requires arg[1] == NSIG / 8 */
625 	print_sigset_addr_len(tcp, tcp->u_arg[0], tcp->u_arg[1]);
626 	tprintf(", %lu", tcp->u_arg[1]);
627 
628 	return RVAL_DECODED;
629 }
630 
631 static void
print_sigqueueinfo(struct tcb * tcp,int sig,unsigned long uinfo)632 print_sigqueueinfo(struct tcb *tcp, int sig, unsigned long uinfo)
633 {
634 	printsignal(sig);
635 	tprints(", ");
636 	printsiginfo_at(tcp, uinfo);
637 }
638 
SYS_FUNC(rt_sigqueueinfo)639 SYS_FUNC(rt_sigqueueinfo)
640 {
641 	tprintf("%lu, ", tcp->u_arg[0]);
642 	print_sigqueueinfo(tcp, tcp->u_arg[1], tcp->u_arg[2]);
643 
644 	return RVAL_DECODED;
645 }
646 
SYS_FUNC(rt_tgsigqueueinfo)647 SYS_FUNC(rt_tgsigqueueinfo)
648 {
649 	tprintf("%lu, %lu, ", tcp->u_arg[0], tcp->u_arg[1]);
650 	print_sigqueueinfo(tcp, tcp->u_arg[2], tcp->u_arg[3]);
651 
652 	return RVAL_DECODED;
653 }
654 
SYS_FUNC(rt_sigtimedwait)655 SYS_FUNC(rt_sigtimedwait)
656 {
657 	/* NB: kernel requires arg[3] == NSIG / 8 */
658 	if (entering(tcp)) {
659 		print_sigset_addr_len(tcp, tcp->u_arg[0], tcp->u_arg[3]);
660 		tprints(", ");
661 		/* This is the only "return" parameter, */
662 		if (tcp->u_arg[1] != 0)
663 			return 0;
664 		/* ... if it's NULL, can decode all on entry */
665 		tprints("NULL, ");
666 	}
667 	else if (tcp->u_arg[1] != 0) {
668 		/* syscall exit, and u_arg[1] wasn't NULL */
669 		printsiginfo_at(tcp, tcp->u_arg[1]);
670 		tprints(", ");
671 	}
672 	else {
673 		/* syscall exit, and u_arg[1] was NULL */
674 		return 0;
675 	}
676 
677 	/*
678 	 * Since the timeout parameter is read by the kernel
679 	 * on entering syscall, it has to be decoded the same way
680 	 * whether the syscall has failed or not.
681 	 */
682 	temporarily_clear_syserror(tcp);
683 	print_timespec(tcp, tcp->u_arg[2]);
684 	restore_cleared_syserror(tcp);
685 
686 	tprintf(", %lu", tcp->u_arg[3]);
687 	return 0;
688 };
689 
SYS_FUNC(restart_syscall)690 SYS_FUNC(restart_syscall)
691 {
692 	tprintf("<... resuming interrupted %s ...>",
693 		tcp->s_prev_ent ? tcp->s_prev_ent->sys_name : "system call");
694 
695 	return RVAL_DECODED;
696 }
697