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      1 /*	$NetBSD: t_ptrace_wait.h,v 1.42 2025/05/09 01:32:25 riastradh Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 2016, 2017, 2018, 2019 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  *
     16  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     17  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     18  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     19  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     20  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     21  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     22  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     23  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     24  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     25  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     26  * POSSIBILITY OF SUCH DAMAGE.
     27  */
     28 
     29 /* Detect plain wait(2) use-case */
     30 #if !defined(TWAIT_WAITPID) && \
     31     !defined(TWAIT_WAITID) && \
     32     !defined(TWAIT_WAIT3) && \
     33     !defined(TWAIT_WAIT4) && \
     34     !defined(TWAIT_WAIT6)
     35 #define TWAIT_WAIT
     36 #endif
     37 
     38 /*
     39  * There are two classes of wait(2)-like functions:
     40  * - wait4(2)-like accepting pid_t, optional options parameter, struct rusage*
     41  * - wait6(2)-like accepting idtype_t, id_t, struct wrusage, mandatory options
     42  *
     43  * The TWAIT_FNAME value is to be used for convenience in debug messages.
     44  *
     45  * The TWAIT_GENERIC() macro is designed to reuse the same unmodified
     46  * code with as many wait(2)-like functions as possible.
     47  *
     48  * In a common use-case wait4(2) and wait6(2)-like function can work the almost
     49  * the same way, however there are few important differences:
     50  * wait6(2) must specify P_PID for idtype to match wpid from wait4(2).
     51  * To behave like wait4(2), wait6(2) the 'options' to wait must include
     52  * WEXITED|WTRUNCATED.
     53  *
     54  * There are two helper macros (they purpose it to mach more than one
     55  * wait(2)-like function):
     56  * The TWAIT_HAVE_STATUS - specifies whether a function can retrieve
     57  *                         status (as integer value).
     58  * The TWAIT_HAVE_PID    - specifies whether a function can request
     59  *                         exact process identifier
     60  * The TWAIT_HAVE_RUSAGE - specifies whether a function can request
     61  *                         the struct rusage value
     62  *
     63  */
     64 
     65 #if defined(TWAIT_WAIT)
     66 #	define TWAIT_FNAME			"wait"
     67 #	define TWAIT_WAIT4TYPE(a,b,c,d)		wait((b))
     68 #	define TWAIT_GENERIC(a,b,c)		wait((b))
     69 #	define TWAIT_HAVE_STATUS		1
     70 #elif defined(TWAIT_WAITPID)
     71 #	define TWAIT_FNAME			"waitpid"
     72 #	define TWAIT_WAIT4TYPE(a,b,c,d)		waitpid((a),(b),(c))
     73 #	define TWAIT_GENERIC(a,b,c)		waitpid((a),(b),(c))
     74 #	define TWAIT_HAVE_PID			1
     75 #	define TWAIT_HAVE_STATUS		1
     76 #	define TWAIT_HAVE_OPTIONS		1
     77 #elif defined(TWAIT_WAITID)
     78 #	define TWAIT_FNAME			"waitid"
     79 #	define TWAIT_GENERIC(a,b,c)		\
     80 		waitid(P_PID,(a),NULL,(c)|WEXITED|WTRAPPED)
     81 #	define TWAIT_WAIT6TYPE(a,b,c,d,e,f)	waitid((a),(b),(f),(d))
     82 #	define TWAIT_HAVE_PID			1
     83 #	define TWAIT_HAVE_OPTIONS		1
     84 #elif defined(TWAIT_WAIT3)
     85 #	define TWAIT_FNAME			"wait3"
     86 #	define TWAIT_WAIT4TYPE(a,b,c,d)		wait3((b),(c),(d))
     87 #	define TWAIT_GENERIC(a,b,c)		wait3((b),(c),NULL)
     88 #	define TWAIT_HAVE_STATUS		1
     89 #	define TWAIT_HAVE_RUSAGE		1
     90 #	define TWAIT_HAVE_OPTIONS		1
     91 #elif defined(TWAIT_WAIT4)
     92 #	define TWAIT_FNAME			"wait4"
     93 #	define TWAIT_WAIT4TYPE(a,b,c,d)		wait4((a),(b),(c),(d))
     94 #	define TWAIT_GENERIC(a,b,c)		wait4((a),(b),(c),NULL)
     95 #	define TWAIT_HAVE_PID			1
     96 #	define TWAIT_HAVE_STATUS		1
     97 #	define TWAIT_HAVE_RUSAGE		1
     98 #	define TWAIT_HAVE_OPTIONS		1
     99 #elif defined(TWAIT_WAIT6)
    100 #	define TWAIT_FNAME			"wait6"
    101 #	define TWAIT_WAIT6TYPE(a,b,c,d,e,f)	wait6((a),(b),(c),(d),(e),(f))
    102 #	define TWAIT_GENERIC(a,b,c)		\
    103 		wait6(P_PID,(a),(b),(c)|WEXITED|WTRAPPED,NULL,NULL)
    104 #	define TWAIT_HAVE_PID			1
    105 #	define TWAIT_HAVE_STATUS		1
    106 #	define TWAIT_HAVE_OPTIONS		1
    107 #endif
    108 
    109 /*
    110  * There are 3 groups of tests:
    111  * - TWAIT_GENERIC()	(wait, wait2, waitpid, wait3, wait4, wait6)
    112  * - TWAIT_WAIT4TYPE()	(wait2, waitpid, wait3, wait4)
    113  * - TWAIT_WAIT6TYPE()	(waitid, wait6)
    114  *
    115  * Tests only in the above categories are allowed. However some tests are not
    116  * possible in the context requested functionality to be verified, therefore
    117  * there are helper macros:
    118  * - TWAIT_HAVE_PID	(wait2, waitpid, waitid, wait4, wait6)
    119  * - TWAIT_HAVE_STATUS	(wait, wait2, waitpid, wait3, wait4, wait6)
    120  * - TWAIT_HAVE_RUSAGE	(wait3, wait4)
    121  * - TWAIT_HAVE_RETPID	(wait, wait2, waitpid, wait3, wait4, wait6)
    122  *
    123  * If there is an intention to test e.g. wait6(2) specific features in the
    124  * ptrace(2) context, find the most matching group and with #ifdefs reduce
    125  * functionality of less featured than wait6(2) interface (TWAIT_WAIT6TYPE).
    126  *
    127  * For clarity never use negative preprocessor checks, like:
    128  *     #if !defined(TWAIT_WAIT4)
    129  * always refer to checks for positive values.
    130  */
    131 
    132 #define TEST_REQUIRE_EQ(x, y)						\
    133 do {									\
    134 	uintmax_t vx = (x);						\
    135 	uintmax_t vy = (y);						\
    136 	int ret = vx == vy;						\
    137 	if (!ret)							\
    138 		ATF_REQUIRE_EQ_MSG(vx, vy,				\
    139 		    "%s(%ju=0x%jx) == %s(%ju=0x%jx)",			\
    140 		    #x, vx, vx, #y, vy, vy);				\
    141 } while (/*CONSTCOND*/0)
    142 
    143 #define TEST_CHECK_EQ(x, y)						\
    144 do {									\
    145 	uintmax_t vx = (x);						\
    146 	uintmax_t vy = (y);						\
    147 	int ret = vx == vy;						\
    148 	if (!ret)							\
    149 		ATF_CHECK_EQ_MSG(vx, vy,				\
    150 		    "%s(%ju=0x%jx) == %s(%ju=0x%jx)",			\
    151 		    #x, vx, vx, #y, vy, vy);				\
    152 } while (/*CONSTCOND*/0)
    153 
    154 #define TEST_CHECK_MEMEQ(x, y, n)					\
    155 do {									\
    156 	const void *vx = (x);						\
    157 	const void *vy = (y);						\
    158 	const size_t vn = (n);						\
    159 	if (__predict_true(memcmp(vx, vy, vn) == 0))			\
    160 		break;							\
    161 	hexdump(#x, vx, vn);						\
    162 	hexdump(#y, vy, vn);						\
    163 	atf_tc_fail_nonfatal("%s != %s (%s = %zu bytes)",		\
    164 	    #x, #y, #n, vn);						\
    165 } while (/*CONSTCOND*/0)
    166 
    167 /*
    168  * A child process cannot call atf functions and expect them to magically
    169  * work like in the parent.
    170  * The printf(3) messaging from a child will not work out of the box as well
    171  * without establishing a communication protocol with its parent. To not
    172  * overcomplicate the tests - do not log from a child and use err(3)/errx(3)
    173  * wrapped with FORKEE_ASSERT()/FORKEE_ASSERTX() as that is guaranteed to work.
    174  */
    175 #define FORKEE_ASSERT_EQ(x, y)						\
    176 do {									\
    177 	uintmax_t vx = (x);						\
    178 	uintmax_t vy = (y);						\
    179 	int ret = vx == vy;						\
    180 	if (!ret)							\
    181 		errx(EXIT_FAILURE, "%s:%d %s(): Assertion failed for: "	\
    182 		    "%s(%jd=0x%jx) == %s(%jd=0x%jx)",			\
    183 		    __FILE__, __LINE__, __func__,			\
    184 		    #x, vx, vx, #y, vy, vy);				\
    185 } while (/*CONSTCOND*/0)
    186 
    187 #define FORKEE_ASSERT_NEQ(x, y)						\
    188 do {									\
    189 	uintmax_t vx = (x);						\
    190 	uintmax_t vy = (y);						\
    191 	int ret = vx != vy;						\
    192 	if (!ret)							\
    193 		errx(EXIT_FAILURE, "%s:%d %s(): Assertion failed for: "	\
    194 		    "%s(%ju=0x%jx) != %s(%ju=0x%jx)",			\
    195 		    __FILE__, __LINE__, __func__,			\
    196 		    #x, vx, vx, #y, vy, vy);				\
    197 } while (/*CONSTCOND*/0)
    198 
    199 __unused	/* used by FORKEE_ASSERT_MEMEQ, otherwise not used */
    200 static void
    201 hexdump(const char *title, const void *buf, size_t len)
    202 {
    203 	const unsigned char *p = buf;
    204 	size_t i;
    205 
    206 	fprintf(stderr, "%s (%zu bytes)\n", title, len);
    207 	for (i = 0; i < len; i++) {
    208 		if ((i % 8) == 0)
    209 			fprintf(stderr, " ");
    210 		fprintf(stderr, " %02hhx", p[i]);
    211 		if ((i % 16) == 15)
    212 			fprintf(stderr, "\n");
    213 	}
    214 	if (i % 16)
    215 		fprintf(stderr, "\n");
    216 }
    217 
    218 #define	FORKEE_ASSERT_MEMEQ(x, y, n)					\
    219 do {									\
    220 	const void *const vx = (x);					\
    221 	const void *const vy = (y);					\
    222 	const size_t vn = (n);						\
    223 									\
    224 	if (__predict_true(memcmp(vx, vy, vn) == 0))			\
    225 		break;							\
    226 	fprintf(stderr, "%s != %s (%s = %zu bytes)\n", #x, #y, #n, vn);	\
    227 	hexdump(#x, vx, vn);						\
    228 	hexdump(#y, vy, vn);						\
    229 	errx(EXIT_FAILURE, "%s:%d %s(): failed",			\
    230 	    __FILE__, __LINE__, __func__);				\
    231 } while (/*CONSTCOND*/0)
    232 
    233 #define FORKEE_ASSERTX(x)						\
    234 do {									\
    235 	int ret = (x);							\
    236 	if (!ret)							\
    237 		errx(EXIT_FAILURE, "%s:%d %s(): Assertion failed for: %s",\
    238 		     __FILE__, __LINE__, __func__, #x);			\
    239 } while (/*CONSTCOND*/0)
    240 
    241 #define FORKEE_ASSERT(x)						\
    242 do {									\
    243 	int ret = (x);							\
    244 	if (!ret)							\
    245 		err(EXIT_FAILURE, "%s:%d %s(): Assertion failed for: %s",\
    246 		     __FILE__, __LINE__, __func__, #x);			\
    247 } while (/*CONSTCOND*/0)
    248 
    249 #define	FORKEE_PTHREAD(x)						\
    250 do {									\
    251 	int _forkee_pthread_error = (x);				\
    252 	if (_forkee_pthread_error) {					\
    253 		errno = _forkee_pthread_error;				\
    254 		err(EXIT_FAILURE, "%s:%d %s(): %s", __FILE__, __LINE__,	\
    255 		    __func__, #x);					\
    256 	}								\
    257 } while (/*CONSTCOND*/0)
    258 
    259 /*
    260  * Simplify logic for functions using general purpose registers add HAVE_GPREGS
    261  *
    262  * For platforms that do not implement all needed calls for simplicity assume
    263  * that they are unsupported at all.
    264  */
    265 #if defined(PT_GETREGS)			\
    266     && defined(PT_SETREGS)		\
    267     && defined(PTRACE_REG_PC)		\
    268     && defined(PTRACE_REG_SET_PC)	\
    269     && defined(PTRACE_REG_SP)		\
    270     && defined(PTRACE_REG_INTRV)
    271 #define HAVE_GPREGS
    272 #endif
    273 
    274 /* Add guards for floating point registers */
    275 #if defined(PT_GETFPREGS)		\
    276     && defined(PT_SETFPREGS)
    277 #define HAVE_FPREGS
    278 #endif
    279 
    280 /* Add guards for cpu debug registers */
    281 #if defined(PT_GETDBREGS)		\
    282     && defined(PT_SETDBREGS)
    283 #define HAVE_DBREGS
    284 #endif
    285 
    286 /*
    287  * If waitid(2) returns because one or more processes have a state change to
    288  * report, 0 is returned.  If an error is detected, a value of -1 is returned
    289  * and errno is set to indicate the error. If WNOHANG is specified and there
    290  * are no stopped, continued or exited children, 0 is returned.
    291  */
    292 #if defined(TWAIT_WAITID)
    293 #define TWAIT_REQUIRE_SUCCESS(a,b)	TEST_REQUIRE_EQ((a), 0)
    294 #define TWAIT_REQUIRE_FAILURE(a,b)	ATF_REQUIRE_ERRNO((a),(b) == -1)
    295 #define FORKEE_REQUIRE_SUCCESS(a,b)	FORKEE_ASSERT_EQ(a, 0)
    296 #define FORKEE_REQUIRE_FAILURE(a,b)	\
    297 	FORKEE_ASSERTX(((a) == errno) && ((b) == -1))
    298 #else
    299 #define TWAIT_REQUIRE_SUCCESS(a,b)	TEST_REQUIRE_EQ((a), (b))
    300 #define TWAIT_REQUIRE_FAILURE(a,b)	ATF_REQUIRE_ERRNO((a),(b) == -1)
    301 #define FORKEE_REQUIRE_SUCCESS(a,b)	FORKEE_ASSERT_EQ(a, b)
    302 #define FORKEE_REQUIRE_FAILURE(a,b)	\
    303 	FORKEE_ASSERTX(((a) == errno) && ((b) == -1))
    304 #endif
    305 
    306 /*
    307  * Helper tools to verify whether status reports exited value
    308  */
    309 #if TWAIT_HAVE_STATUS
    310 static void __used
    311 validate_status_exited(int status, int expected)
    312 {
    313         ATF_REQUIRE_MSG(WIFEXITED(status), "Reported !exited process");
    314         ATF_REQUIRE_MSG(!WIFCONTINUED(status), "Reported continued process");
    315         ATF_REQUIRE_MSG(!WIFSIGNALED(status), "Reported signaled process");
    316         ATF_REQUIRE_MSG(!WIFSTOPPED(status), "Reported stopped process");
    317 
    318 	ATF_REQUIRE_EQ_MSG(WEXITSTATUS(status), expected,
    319 	    "The process has exited with invalid value %d != %d",
    320 	    WEXITSTATUS(status), expected);
    321 }
    322 
    323 static void __used
    324 forkee_status_exited(int status, int expected)
    325 {
    326 	FORKEE_ASSERTX(WIFEXITED(status));
    327 	FORKEE_ASSERTX(!WIFCONTINUED(status));
    328 	FORKEE_ASSERTX(!WIFSIGNALED(status));
    329 	FORKEE_ASSERTX(!WIFSTOPPED(status));
    330 
    331 	FORKEE_ASSERT_EQ(WEXITSTATUS(status), expected);
    332 }
    333 
    334 static void __used
    335 validate_status_continued(int status)
    336 {
    337 	ATF_REQUIRE_MSG(!WIFEXITED(status), "Reported exited process");
    338 	ATF_REQUIRE_MSG(WIFCONTINUED(status), "Reported !continued process");
    339 	ATF_REQUIRE_MSG(!WIFSIGNALED(status), "Reported signaled process");
    340 	ATF_REQUIRE_MSG(!WIFSTOPPED(status), "Reported stopped process");
    341 }
    342 
    343 static void __used
    344 forkee_status_continued(int status)
    345 {
    346 	FORKEE_ASSERTX(!WIFEXITED(status));
    347 	FORKEE_ASSERTX(WIFCONTINUED(status));
    348 	FORKEE_ASSERTX(!WIFSIGNALED(status));
    349 	FORKEE_ASSERTX(!WIFSTOPPED(status));
    350 }
    351 
    352 static void __used
    353 validate_status_signaled(int status, int expected_termsig, int expected_core)
    354 {
    355 	ATF_REQUIRE_MSG(!WIFEXITED(status), "Reported exited process");
    356 	ATF_REQUIRE_MSG(!WIFCONTINUED(status), "Reported continued process");
    357 	ATF_REQUIRE_MSG(WIFSIGNALED(status), "Reported !signaled process");
    358 	ATF_REQUIRE_MSG(!WIFSTOPPED(status), "Reported stopped process");
    359 
    360 	ATF_REQUIRE_EQ_MSG(WTERMSIG(status), expected_termsig,
    361 	    "Unexpected signal received");
    362 
    363 	ATF_REQUIRE_EQ_MSG(!!WCOREDUMP(status), expected_core,
    364 	    "Unexpectedly core file %s generated", expected_core ? "not" : "");
    365 }
    366 
    367 static void __used
    368 forkee_status_signaled(int status, int expected_termsig, int expected_core)
    369 {
    370 	FORKEE_ASSERTX(!WIFEXITED(status));
    371 	FORKEE_ASSERTX(!WIFCONTINUED(status));
    372 	FORKEE_ASSERTX(WIFSIGNALED(status));
    373 	FORKEE_ASSERTX(!WIFSTOPPED(status));
    374 
    375 	FORKEE_ASSERT_EQ(WTERMSIG(status), expected_termsig);
    376 	FORKEE_ASSERT_EQ(!!WCOREDUMP(status), expected_core);
    377 }
    378 
    379 static void __used
    380 validate_status_stopped(int status, int expected)
    381 {
    382 	ATF_REQUIRE_MSG(!WIFEXITED(status), "Reported exited process");
    383 	ATF_REQUIRE_MSG(!WIFCONTINUED(status), "Reported continued process");
    384 	ATF_REQUIRE_MSG(!WIFSIGNALED(status), "Reported signaled process");
    385 	ATF_REQUIRE_MSG(WIFSTOPPED(status), "Reported !stopped process");
    386 
    387 	char st[128], ex[128];
    388 	strlcpy(st, strsignal(WSTOPSIG(status)), sizeof(st));
    389 	strlcpy(ex, strsignal(expected), sizeof(ex));
    390 
    391 	ATF_REQUIRE_EQ_MSG(WSTOPSIG(status), expected,
    392 	    "Unexpected stop signal received [%s] != [%s]", st, ex);
    393 }
    394 
    395 static void __used
    396 forkee_status_stopped(int status, int expected)
    397 {
    398 	FORKEE_ASSERTX(!WIFEXITED(status));
    399 	FORKEE_ASSERTX(!WIFCONTINUED(status));
    400 	FORKEE_ASSERTX(!WIFSIGNALED(status));
    401 	FORKEE_ASSERTX(WIFSTOPPED(status));
    402 
    403 	FORKEE_ASSERT_EQ(WSTOPSIG(status), expected);
    404 }
    405 #else
    406 #define validate_status_exited(a,b)
    407 #define forkee_status_exited(a,b)
    408 #define validate_status_continued(a,b)
    409 #define forkee_status_continued(a,b)
    410 #define validate_status_signaled(a,b,c)
    411 #define forkee_status_signaled(a,b,c)
    412 #define validate_status_stopped(a,b)
    413 #define forkee_status_stopped(a,b)
    414 #endif
    415 
    416 /* This function is currently designed to be run in the main/parent process */
    417 static void __used
    418 await_zombie_raw(pid_t process, useconds_t ms)
    419 {
    420 	struct kinfo_proc2 p;
    421 	size_t len = sizeof(p);
    422 
    423 	const int name[] = {
    424 		[0] = CTL_KERN,
    425 		[1] = KERN_PROC2,
    426 		[2] = KERN_PROC_PID,
    427 		[3] = process,
    428 		[4] = sizeof(p),
    429 		[5] = 1
    430 	};
    431 
    432 	const size_t namelen = __arraycount(name);
    433 
    434 	/* Await the process becoming a zombie */
    435 	while(1) {
    436 		ATF_REQUIRE(sysctl(name, namelen, &p, &len, NULL, 0) == 0);
    437 
    438 		if (p.p_stat == LSZOMB)
    439 			break;
    440 
    441 		if (ms > 0) {
    442 			ATF_REQUIRE(usleep(ms) == 0);
    443 		}
    444 	}
    445 }
    446 
    447 static void __used
    448 await_zombie(pid_t process)
    449 {
    450 
    451 	await_zombie_raw(process, 1000);
    452 }
    453 
    454 static void __used
    455 await_stopped(pid_t process)
    456 {
    457 	struct kinfo_proc2 p;
    458 	size_t len = sizeof(p);
    459 
    460 	const int name[] = {
    461 		[0] = CTL_KERN,
    462 		[1] = KERN_PROC2,
    463 		[2] = KERN_PROC_PID,
    464 		[3] = process,
    465 		[4] = sizeof(p),
    466 		[5] = 1
    467 	};
    468 
    469 	const size_t namelen = __arraycount(name);
    470 
    471 	/* Await the process becoming a zombie */
    472 	while(1) {
    473 		ATF_REQUIRE(sysctl(name, namelen, &p, &len, NULL, 0) == 0);
    474 
    475 		if (p.p_stat == LSSTOP)
    476 			break;
    477 
    478 		ATF_REQUIRE(usleep(1000) == 0);
    479 	}
    480 }
    481 
    482 static pid_t __used
    483 await_stopped_child(pid_t process)
    484 {
    485 	struct kinfo_proc2 *p = NULL;
    486 	size_t i, len;
    487 	pid_t child = -1;
    488 
    489 	int name[] = {
    490 		[0] = CTL_KERN,
    491 		[1] = KERN_PROC2,
    492 		[2] = KERN_PROC_ALL,
    493 		[3] = 0,
    494 		[4] = sizeof(struct kinfo_proc2),
    495 		[5] = 0
    496 	};
    497 
    498 	const size_t namelen = __arraycount(name);
    499 
    500 	/* Await the process becoming a zombie */
    501 	while(1) {
    502 		name[5] = 0;
    503 
    504 		FORKEE_ASSERT_EQ(sysctl(name, namelen, 0, &len, NULL, 0), 0);
    505 
    506 		FORKEE_ASSERT_EQ(reallocarr(&p,
    507 		                            len,
    508 		                            sizeof(struct kinfo_proc2)), 0);
    509 
    510 		name[5] = len;
    511 
    512 		FORKEE_ASSERT_EQ(sysctl(name, namelen, p, &len, NULL, 0), 0);
    513 
    514 		for (i = 0; i < len/sizeof(struct kinfo_proc2); i++) {
    515 			if (p[i].p_pid == getpid())
    516 				continue;
    517 			if (p[i].p_ppid != process)
    518 				continue;
    519 			if (p[i].p_stat != LSSTOP)
    520 				continue;
    521 			child = p[i].p_pid;
    522 			break;
    523 		}
    524 
    525 		if (child != -1)
    526 			break;
    527 
    528 		FORKEE_ASSERT_EQ(usleep(1000), 0);
    529 	}
    530 
    531 	/* Free the buffer */
    532 	FORKEE_ASSERT_EQ(reallocarr(&p, 0, sizeof(struct kinfo_proc2)), 0);
    533 
    534 	return child;
    535 }
    536 
    537 static void __used
    538 await_collected(pid_t process)
    539 {
    540 	struct kinfo_proc2 p;
    541 	size_t len = sizeof(p);
    542 
    543 	const int name[] = {
    544 		[0] = CTL_KERN,
    545 		[1] = KERN_PROC2,
    546 		[2] = KERN_PROC_PID,
    547 		[3] = process,
    548 		[4] = sizeof(p),
    549 		[5] = 1
    550 	};
    551 
    552 	const size_t namelen = __arraycount(name);
    553 
    554 	/* Await the process to disappear */
    555 	while(1) {
    556 		FORKEE_ASSERT_EQ(sysctl(name, namelen, &p, &len, NULL, 0), 0);
    557 		if (len == 0)
    558 			break;
    559 
    560 		ATF_REQUIRE(usleep(1000) == 0);
    561 	}
    562 }
    563 
    564 /* Happy number sequence -- this function is used to just consume cpu cycles */
    565 #define	HAPPY_NUMBER	1
    566 
    567 /* If n is not happy then its sequence ends in the cycle:
    568  * 4, 16, 37, 58, 89, 145, 42, 20, 4, ... */
    569 #define	SAD_NUMBER	4
    570 
    571 /* Calculate the sum of the squares of the digits of n */
    572 static unsigned __used
    573 dsum(unsigned n)
    574 {
    575 	unsigned sum, x;
    576 	for (sum = 0; n; n /= 10) {
    577 		x = n % 10;
    578 		sum += x * x;
    579 	}
    580 	return sum;
    581 }
    582 
    583 /*
    584  * XXX: Disabled optimization is required to make tests for hardware assisted
    585  * traps in .text functional
    586  *
    587  * Tested with GCC 5.4 on NetBSD 7.99.47 amd64
    588  */
    589 static int __used
    590 #ifdef __clang__
    591 __attribute__((__optnone__))
    592 #else
    593 __attribute__((__optimize__("O0")))
    594 #endif
    595 check_happy(unsigned n)
    596 {
    597 	for (;;) {
    598 		unsigned total = dsum(n);
    599 
    600 		if (total == HAPPY_NUMBER)
    601 			return 1;
    602 		if (total == SAD_NUMBER)
    603 			return 0;
    604 
    605 		n = total;
    606 	}
    607 }
    608 
    609 static void * __used
    610 infinite_thread(void *arg __unused)
    611 {
    612 
    613         while (true)
    614                 continue;
    615 
    616         __unreachable();
    617 }
    618 
    619 static int __used
    620 clone_func(void *arg)
    621 {
    622 	int ret;
    623 
    624 	ret = (int)(intptr_t)arg;
    625 
    626 	return ret;
    627 }
    628 
    629 #if defined(HAVE_DBREGS)
    630 static bool __used
    631 can_we_set_dbregs(void)
    632 {
    633 	static long euid = -1;
    634 	static int user_set_dbregs  = -1;
    635 	size_t user_set_dbregs_len = sizeof(user_set_dbregs);
    636 
    637 	if (euid == -1)
    638 		euid = geteuid();
    639 
    640 	if (euid == 0)
    641 		return true;
    642 
    643 	if (user_set_dbregs == -1) {
    644 		if (sysctlbyname("security.models.extensions.user_set_dbregs",
    645 			&user_set_dbregs, &user_set_dbregs_len, NULL, 0)
    646 			== -1) {
    647 			return false;
    648 		}
    649 	}
    650 
    651 	if (user_set_dbregs > 0)
    652 		return true;
    653 	else
    654 		return false;
    655 }
    656 #endif
    657 
    658 static bool __used
    659 get_user_va0_disable(void)
    660 {
    661 	static int user_va0_disable = -1;
    662 	size_t user_va0_disable_len = sizeof(user_va0_disable);
    663 
    664 	if (user_va0_disable == -1) {
    665 		if (sysctlbyname("vm.user_va0_disable",
    666 			&user_va0_disable, &user_va0_disable_len, NULL, 0)
    667 			== -1) {
    668 			return true;
    669 		}
    670 	}
    671 
    672 	if (user_va0_disable > 0)
    673 		return true;
    674 	else
    675 		return false;
    676 }
    677 
    678 static bool __used
    679 can_we_write_to_text(pid_t pid)
    680 {
    681 	int mib[3];
    682 	int paxflags;
    683 	size_t len = sizeof(int);
    684 
    685 	mib[0] = CTL_PROC;
    686 	mib[1] = pid;
    687 	mib[2] = PROC_PID_PAXFLAGS;
    688 
    689 	if (sysctl(mib, 3, &paxflags, &len, NULL, 0) == -1)
    690 		return false;
    691 
    692 	return !(paxflags & CTL_PROC_PAXFLAGS_MPROTECT);
    693 }
    694 
    695 static void __used
    696 trigger_trap(void)
    697 {
    698 
    699 	/* Software breakpoint causes CPU trap, translated to SIGTRAP */
    700 #ifdef PTRACE_BREAKPOINT_ASM
    701 	PTRACE_BREAKPOINT_ASM;
    702 #else
    703 	/* port me */
    704 #endif
    705 }
    706 
    707 static void __used
    708 trigger_segv(void)
    709 {
    710 	static volatile char *ptr = NULL;
    711 
    712 	/* Access to unmapped memory causes CPU trap, translated to SIGSEGV */
    713 	*ptr = 1;
    714 }
    715 
    716 static void __used
    717 trigger_ill(void)
    718 {
    719 
    720 	/* Illegal instruction causes CPU trap, translated to SIGILL */
    721 #ifdef PTRACE_ILLEGAL_ASM
    722 #ifndef __mips__ /* To avoid GXemul crash */
    723 	PTRACE_ILLEGAL_ASM;
    724 #endif
    725 #else
    726 	/* port me */
    727 #endif
    728 }
    729 
    730 #include <fenv.h>
    731 
    732 #if (__arm__ && !__SOFTFP__) || __aarch64__
    733 #include <ieeefp.h> /* only need for ARM Cortex/Neon hack */
    734 
    735 static bool __used
    736 are_fpu_exceptions_supported(void)
    737 {
    738 	/*
    739 	 * Some NEON fpus do not trap on IEEE 754 FP exceptions.
    740 	 * Skip these tests if running on them and compiled for
    741 	 * hard float.
    742 	 */
    743 	if (0 == fpsetmask(fpsetmask(FP_X_INV)))
    744 		return false;
    745 	return true;
    746 }
    747 #elif defined __riscv__
    748 #define are_fpu_exceptions_supported() 0
    749 #else
    750 #define are_fpu_exceptions_supported() 1
    751 #endif
    752 
    753 volatile double ignore_result;
    754 
    755 static void __used
    756 trigger_fpe(void)
    757 {
    758 #if __i386__ || __x86_64__
    759 	/*
    760 	 * XXX
    761 	 * Hack for QEMU bug #1668041, by which floating-point division by
    762 	 * zero is not trapped correctly. Also, assertions for si_code in
    763 	 * ptrace_signal_wait.h are commented out. Clean them up after the
    764 	 * bug is fixed.
    765 	 */
    766 	volatile int a, b;
    767 #else
    768 	volatile double a, b;
    769 #endif
    770 
    771 	a = getpid();
    772 	b = atoi("0");
    773 
    774 #ifdef __HAVE_FENV
    775 	feenableexcept(FE_ALL_EXCEPT);
    776 #endif
    777 
    778 	/* Division by zero causes CPU trap, translated to SIGFPE */
    779 	ignore_result = (int)(a / b);
    780 }
    781 
    782 static void __used
    783 trigger_bus(void)
    784 {
    785 	FILE *fp;
    786 	char *p;
    787 
    788 	/* Open an empty file for writing. */
    789 	fp = tmpfile();
    790 	FORKEE_ASSERT_NEQ((uintptr_t)fp, (uintptr_t)NULL);
    791 
    792 	/*
    793 	 * Map an empty file with mmap(2) to a pointer.
    794 	 *
    795 	 * PROT_READ handles read-modify-write sequences emitted for
    796 	 * certain combinations of CPUs and compilers (e.g. Alpha AXP).
    797 	 */
    798 	p = mmap(0, 1, PROT_READ|PROT_WRITE, MAP_PRIVATE, fileno(fp), 0);
    799 	FORKEE_ASSERT_NEQ((uintptr_t)p, (uintptr_t)MAP_FAILED);
    800 
    801 	/* Invalid memory access causes CPU trap, translated to SIGBUS */
    802 	*p = 'a';
    803 }
    804 
    805 struct lwp_event_count {
    806 	lwpid_t lec_lwp;
    807 	int lec_count;
    808 };
    809 
    810 static int * __used
    811 find_event_count(struct lwp_event_count list[], lwpid_t lwp, size_t max_lwps)
    812 {
    813 	size_t i;
    814 
    815 	for (i = 0; i < max_lwps; i++) {
    816 		if (list[i].lec_lwp == 0)
    817 			list[i].lec_lwp = lwp;
    818 		if (list[i].lec_lwp == lwp)
    819 			return &list[i].lec_count;
    820 	}
    821 
    822 	atf_tc_fail("More LWPs reported than expected");
    823 }
    824 
    825 #define FIND_EVENT_COUNT(list, lwp)			\
    826 	find_event_count(list, lwp, __arraycount(list))
    827 
    828 #if defined(TWAIT_HAVE_PID)
    829 #define ATF_TP_ADD_TC_HAVE_PID(a,b)	ATF_TP_ADD_TC(a,b)
    830 #else
    831 #define ATF_TP_ADD_TC_HAVE_PID(a,b)
    832 #endif
    833 
    834 #if defined(TWAIT_HAVE_STATUS)
    835 #define ATF_TP_ADD_TC_HAVE_STATUS(a,b)	ATF_TP_ADD_TC(a,b)
    836 #else
    837 #define ATF_TP_ADD_TC_HAVE_STATUS(a,b)
    838 #endif
    839 
    840 #if defined(TWAIT_HAVE_STATUS) && (defined(__i386__) || defined(__x86_64__))
    841 #define ATF_TP_ADD_TC_HAVE_STATUS_X86(a,b)	ATF_TP_ADD_TC(a,b)
    842 #else
    843 #define ATF_TP_ADD_TC_HAVE_STATUS_X86(a,b)
    844 #endif
    845 
    846 #if defined(HAVE_GPREGS)
    847 #define ATF_TP_ADD_TC_HAVE_GPREGS(a,b)	ATF_TP_ADD_TC(a,b)
    848 #else
    849 #define ATF_TP_ADD_TC_HAVE_GPREGS(a,b)
    850 #endif
    851 
    852 #if defined(HAVE_FPREGS)
    853 #define ATF_TP_ADD_TC_HAVE_FPREGS(a,b)	ATF_TP_ADD_TC(a,b)
    854 #else
    855 #define ATF_TP_ADD_TC_HAVE_FPREGS(a,b)
    856 #endif
    857 
    858 #if defined(HAVE_DBREGS)
    859 #define ATF_TP_ADD_TC_HAVE_DBREGS(a,b) ATF_TP_ADD_TC(a,b)
    860 #else
    861 #define ATF_TP_ADD_TC_HAVE_DBREGS(a,b)
    862 #endif
    863 
    864 #if defined(PT_STEP)
    865 #define ATF_TP_ADD_TC_PT_STEP(a,b)	ATF_TP_ADD_TC(a,b)
    866 #else
    867 #define ATF_TP_ADD_TC_PT_STEP(a,b)
    868 #endif
    869