[lttng-ust.git] / src / liblttng-ust-fork / ustfork.c

/*
 * SPDX-License-Identifier: LGPL-2.1-only
 *
 * Copyright (C) 2009  Pierre-Marc Fournier
 * Copyright (C) 2011-2012  Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
 */

/* Has to be included first to override dlfcn.h */
#include <common/compat/dlfcn.h>

#include <unistd.h>
#include <stdio.h>
#include <signal.h>
#include <sched.h>
#include <stdarg.h>
#include <errno.h>

#include <lttng/ust-fork.h>

pid_t fork(void)
{
	static pid_t (*plibc_func)(void) = NULL;
	sigset_t sigset;
	pid_t retval;
	int saved_errno;

	if (plibc_func == NULL) {
		plibc_func = dlsym(RTLD_NEXT, "fork");
		if (plibc_func == NULL) {
			fprintf(stderr, "libustfork: unable to find \"fork\" symbol\n");
			errno = ENOSYS;
			return -1;
		}
	}

	lttng_ust_before_fork(&sigset);
	/* Do the real fork */
	retval = plibc_func();
	saved_errno = errno;
	if (retval == 0) {
		/* child */
		lttng_ust_after_fork_child(&sigset);
	} else {
		lttng_ust_after_fork_parent(&sigset);
	}
	errno = saved_errno;
	return retval;
}

int daemon(int nochdir, int noclose)
{
	static int (*plibc_func)(int nochdir, int noclose) = NULL;
	sigset_t sigset;
	int retval;
	int saved_errno;

	if (plibc_func == NULL) {
		plibc_func = dlsym(RTLD_NEXT, "daemon");
		if (plibc_func == NULL) {
			fprintf(stderr, "libustfork: unable to find \"daemon\" symbol\n");
			errno = ENOSYS;
			return -1;
		}
	}

	lttng_ust_before_fork(&sigset);
	/* Do the real daemon call */
	retval = plibc_func(nochdir, noclose);
	saved_errno = errno;
	if (retval == 0) {
		/* child, parent called _exit() directly */
		lttng_ust_after_fork_child(&sigset);
	} else {
		/* on error in the parent */
		lttng_ust_after_fork_parent(&sigset);
	}
	errno = saved_errno;
	return retval;
}

int setuid(uid_t uid)
{
	static int (*plibc_func)(uid_t uid) = NULL;
	int retval;
	int saved_errno;

	if (plibc_func == NULL) {
		plibc_func = dlsym(RTLD_NEXT, "setuid");
		if (plibc_func == NULL) {
			fprintf(stderr, "libustfork: unable to find \"setuid\" symbol\n");
			errno = ENOSYS;
			return -1;
		}
	}

	/* Do the real setuid */
	retval = plibc_func(uid);
	saved_errno = errno;

	lttng_ust_after_setuid();

	errno = saved_errno;
	return retval;
}

int setgid(gid_t gid)
{
	static int (*plibc_func)(gid_t gid) = NULL;
	int retval;
	int saved_errno;

	if (plibc_func == NULL) {
		plibc_func = dlsym(RTLD_NEXT, "setgid");
		if (plibc_func == NULL) {
			fprintf(stderr, "libustfork: unable to find \"setgid\" symbol\n");
			errno = ENOSYS;
			return -1;
		}
	}

	/* Do the real setgid */
	retval = plibc_func(gid);
	saved_errno = errno;

	lttng_ust_after_setgid();

	errno = saved_errno;
	return retval;
}

int seteuid(uid_t euid)
{
	static int (*plibc_func)(uid_t euid) = NULL;
	int retval;
	int saved_errno;

	if (plibc_func == NULL) {
		plibc_func = dlsym(RTLD_NEXT, "seteuid");
		if (plibc_func == NULL) {
			fprintf(stderr, "libustfork: unable to find \"seteuid\" symbol\n");
			errno = ENOSYS;
			return -1;
		}
	}

	/* Do the real seteuid */
	retval = plibc_func(euid);
	saved_errno = errno;

	lttng_ust_after_seteuid();

	errno = saved_errno;
	return retval;
}

int setegid(gid_t egid)
{
	static int (*plibc_func)(gid_t egid) = NULL;
	int retval;
	int saved_errno;

	if (plibc_func == NULL) {
		plibc_func = dlsym(RTLD_NEXT, "setegid");
		if (plibc_func == NULL) {
			fprintf(stderr, "libustfork: unable to find \"setegid\" symbol\n");
			errno = ENOSYS;
			return -1;
		}
	}

	/* Do the real setegid */
	retval = plibc_func(egid);
	saved_errno = errno;

	lttng_ust_after_setegid();

	errno = saved_errno;
	return retval;
}

int setreuid(uid_t ruid, uid_t euid)
{
	static int (*plibc_func)(uid_t ruid, uid_t euid) = NULL;
	int retval;
	int saved_errno;

	if (plibc_func == NULL) {
		plibc_func = dlsym(RTLD_NEXT, "setreuid");
		if (plibc_func == NULL) {
			fprintf(stderr, "libustfork: unable to find \"setreuid\" symbol\n");
			errno = ENOSYS;
			return -1;
		}
	}

	/* Do the real setreuid */
	retval = plibc_func(ruid, euid);
	saved_errno = errno;

	lttng_ust_after_setreuid();

	errno = saved_errno;
	return retval;
}

int setregid(gid_t rgid, gid_t egid)
{
	static int (*plibc_func)(gid_t rgid, gid_t egid) = NULL;
	int retval;
	int saved_errno;

	if (plibc_func == NULL) {
		plibc_func = dlsym(RTLD_NEXT, "setregid");
		if (plibc_func == NULL) {
			fprintf(stderr, "libustfork: unable to find \"setregid\" symbol\n");
			errno = ENOSYS;
			return -1;
		}
	}

	/* Do the real setregid */
	retval = plibc_func(rgid, egid);
	saved_errno = errno;

	lttng_ust_after_setregid();

	errno = saved_errno;
	return retval;
}

#ifdef __linux__

struct user_desc;

struct ustfork_clone_info {
	int (*fn)(void *);
	void *arg;
	sigset_t sigset;
};

static int clone_fn(void *arg)
{
	struct ustfork_clone_info *info = (struct ustfork_clone_info *) arg;

	/* clone is now done and we are in child */
	lttng_ust_after_fork_child(&info->sigset);
	return info->fn(info->arg);
}

int clone(int (*fn)(void *), void *child_stack, int flags, void *arg, ...)
{
	static int (*plibc_func)(int (*fn)(void *), void *child_stack,
			int flags, void *arg, pid_t *ptid,
			struct user_desc *tls, pid_t *ctid) = NULL;
	/* var args */
	pid_t *ptid;
	struct user_desc *tls;
	pid_t *ctid;
	/* end of var args */
	va_list ap;
	int retval;
	int saved_errno;

	va_start(ap, arg);
	ptid = va_arg(ap, pid_t *);
	tls = va_arg(ap, struct user_desc *);
	ctid = va_arg(ap, pid_t *);
	va_end(ap);

	if (plibc_func == NULL) {
		plibc_func = dlsym(RTLD_NEXT, "clone");
		if (plibc_func == NULL) {
			fprintf(stderr, "libustfork: unable to find \"clone\" symbol.\n");
			errno = ENOSYS;
			return -1;
		}
	}

	if (flags & CLONE_VM) {
		/*
		 * Creating a thread, no need to intervene, just pass on
		 * the arguments.
		 */
		retval = plibc_func(fn, child_stack, flags, arg, ptid,
				tls, ctid);
		saved_errno = errno;
	} else {
		/* Creating a real process, we need to intervene. */
		struct ustfork_clone_info info = { .fn = fn, .arg = arg };

		lttng_ust_before_fork(&info.sigset);
		retval = plibc_func(clone_fn, child_stack, flags, &info,
				ptid, tls, ctid);
		saved_errno = errno;
		/* The child doesn't get here. */
		lttng_ust_after_fork_parent(&info.sigset);
	}
	errno = saved_errno;
	return retval;
}

int setns(int fd, int nstype)
{
	static int (*plibc_func)(int fd, int nstype) = NULL;
	int retval;
	int saved_errno;

	if (plibc_func == NULL) {
		plibc_func = dlsym(RTLD_NEXT, "setns");
		if (plibc_func == NULL) {
			fprintf(stderr, "libustfork: unable to find \"setns\" symbol\n");
			errno = ENOSYS;
			return -1;
		}
	}

	/* Do the real setns */
	retval = plibc_func(fd, nstype);
	saved_errno = errno;

	lttng_ust_after_setns();

	errno = saved_errno;
	return retval;
}

int unshare(int flags)
{
	static int (*plibc_func)(int flags) = NULL;
	int retval;
	int saved_errno;

	if (plibc_func == NULL) {
		plibc_func = dlsym(RTLD_NEXT, "unshare");
		if (plibc_func == NULL) {
			fprintf(stderr, "libustfork: unable to find \"unshare\" symbol\n");
			errno = ENOSYS;
			return -1;
		}
	}

	/* Do the real setns */
	retval = plibc_func(flags);
	saved_errno = errno;

	lttng_ust_after_unshare();

	errno = saved_errno;
	return retval;
}

int setresuid(uid_t ruid, uid_t euid, uid_t suid)
{
	static int (*plibc_func)(uid_t ruid, uid_t euid, uid_t suid) = NULL;
	int retval;
	int saved_errno;

	if (plibc_func == NULL) {
		plibc_func = dlsym(RTLD_NEXT, "setresuid");
		if (plibc_func == NULL) {
			fprintf(stderr, "libustfork: unable to find \"setresuid\" symbol\n");
			errno = ENOSYS;
			return -1;
		}
	}

	/* Do the real setresuid */
	retval = plibc_func(ruid, euid, suid);
	saved_errno = errno;

	lttng_ust_after_setresuid();

	errno = saved_errno;
	return retval;
}

int setresgid(gid_t rgid, gid_t egid, gid_t sgid)
{
	static int (*plibc_func)(gid_t rgid, gid_t egid, gid_t sgid) = NULL;
	int retval;
	int saved_errno;

	if (plibc_func == NULL) {
		plibc_func = dlsym(RTLD_NEXT, "setresgid");
		if (plibc_func == NULL) {
			fprintf(stderr, "libustfork: unable to find \"setresgid\" symbol\n");
			errno = ENOSYS;
			return -1;
		}
	}

	/* Do the real setresgid */
	retval = plibc_func(rgid, egid, sgid);
	saved_errno = errno;

	lttng_ust_after_setresgid();

	errno = saved_errno;
	return retval;
}

#elif defined (__FreeBSD__)

pid_t rfork(int flags)
{
	static pid_t (*plibc_func)(void) = NULL;
	sigset_t sigset;
	pid_t retval;
	int saved_errno;

	if (plibc_func == NULL) {
		plibc_func = dlsym(RTLD_NEXT, "rfork");
		if (plibc_func == NULL) {
			fprintf(stderr, "libustfork: unable to find \"rfork\" symbol\n");
			errno = ENOSYS;
			return -1;
		}
	}

	lttng_ust_before_fork(&sigset);
	/* Do the real rfork */
	retval = plibc_func();
	saved_errno = errno;
	if (retval == 0) {
		/* child */
		lttng_ust_after_fork_child(&sigset);
	} else {
		lttng_ust_after_fork_parent(&sigset);
	}
	errno = saved_errno;
	return retval;
}

/*
 * On BSD, no need to override vfork, because it runs in the context of
 * the parent, with parent waiting until execve or exit is executed in
 * the child.
 */

#else
#warning "Unknown OS. You might want to ensure that fork/clone/vfork/fork handling is complete."
#endif
Commit	Line	Data
e822f505	1	/*
c0c0989a MJ	2	* SPDX-License-Identifier: LGPL-2.1-only
c0c0989a MJ	3	*
e822f505	4	* Copyright (C) 2009 Pierre-Marc Fournier
3678c8aa	5	* Copyright (C) 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
2d99476b PMF	6	*/
2d99476b PMF	7
9d315d6d MJ	8	/* Has to be included first to override dlfcn.h */
	9	#include <common/compat/dlfcn.h>
	10
2d99476b PMF	11	#include <unistd.h>
2d99476b PMF	12	#include <stdio.h>
df793c55	13	#include <signal.h>
616ed36a PMF	14	#include <sched.h>
616ed36a PMF	15	#include <stdarg.h>
eb2b066f	16	#include <errno.h>
2d99476b	17
d0c8f180	18	#include <lttng/ust-fork.h>
e822f505	19
2d99476b PMF	20	pid_t fork(void)
	21	{
	22	static pid_t (*plibc_func)(void) = NULL;
7f0aeeba	23	sigset_t sigset;
2d99476b	24	pid_t retval;
111902ab	25	int saved_errno;
2d99476b	26
e822f505	27	if (plibc_func == NULL) {
2d99476b	28	plibc_func = dlsym(RTLD_NEXT, "fork");
e822f505 MD	29	if (plibc_func == NULL) {
e822f505 MD	30	fprintf(stderr, "libustfork: unable to find \"fork\" symbol\n");
3678c8aa	31	errno = ENOSYS;
2c10b7fd	32	return -1;
2d99476b PMF	33	}
	34	}
	35
d0c8f180	36	lttng_ust_before_fork(&sigset);
df793c55	37	/* Do the real fork */
2d99476b	38	retval = plibc_func();
111902ab	39	saved_errno = errno;
e822f505	40	if (retval == 0) {
df793c55	41	/* child */
d0c8f180	42	lttng_ust_after_fork_child(&sigset);
e822f505	43	} else {
d0c8f180	44	lttng_ust_after_fork_parent(&sigset);
df793c55	45	}
111902ab	46	errno = saved_errno;
2d99476b PMF	47	return retval;
2d99476b PMF	48	}
97b042a3	49
2f6150e9 MD	50	int daemon(int nochdir, int noclose)
	51	{
	52	static int (*plibc_func)(int nochdir, int noclose) = NULL;
	53	sigset_t sigset;
	54	int retval;
111902ab	55	int saved_errno;
2f6150e9 MD	56
	57	if (plibc_func == NULL) {
	58	plibc_func = dlsym(RTLD_NEXT, "daemon");
	59	if (plibc_func == NULL) {
	60	fprintf(stderr, "libustfork: unable to find \"daemon\" symbol\n");
	61	errno = ENOSYS;
	62	return -1;
	63	}
	64	}
	65
d0c8f180	66	lttng_ust_before_fork(&sigset);
2f6150e9 MD	67	/* Do the real daemon call */
2f6150e9 MD	68	retval = plibc_func(nochdir, noclose);
111902ab	69	saved_errno = errno;
2f6150e9 MD	70	if (retval == 0) {
2f6150e9 MD	71	/* child, parent called _exit() directly */
d0c8f180	72	lttng_ust_after_fork_child(&sigset);
2f6150e9 MD	73	} else {
2f6150e9 MD	74	/* on error in the parent */
d0c8f180	75	lttng_ust_after_fork_parent(&sigset);
2f6150e9	76	}
111902ab	77	errno = saved_errno;
2f6150e9 MD	78	return retval;
	79	}
	80
fca2f191 MJ	81	int setuid(uid_t uid)
	82	{
	83	static int (*plibc_func)(uid_t uid) = NULL;
	84	int retval;
	85	int saved_errno;
	86
	87	if (plibc_func == NULL) {
	88	plibc_func = dlsym(RTLD_NEXT, "setuid");
	89	if (plibc_func == NULL) {
	90	fprintf(stderr, "libustfork: unable to find \"setuid\" symbol\n");
	91	errno = ENOSYS;
	92	return -1;
	93	}
	94	}
	95
	96	/* Do the real setuid */
	97	retval = plibc_func(uid);
	98	saved_errno = errno;
	99
d0c8f180	100	lttng_ust_after_setuid();
fca2f191 MJ	101
	102	errno = saved_errno;
	103	return retval;
	104	}
	105
	106	int setgid(gid_t gid)
	107	{
	108	static int (*plibc_func)(gid_t gid) = NULL;
	109	int retval;
	110	int saved_errno;
	111
	112	if (plibc_func == NULL) {
	113	plibc_func = dlsym(RTLD_NEXT, "setgid");
	114	if (plibc_func == NULL) {
	115	fprintf(stderr, "libustfork: unable to find \"setgid\" symbol\n");
	116	errno = ENOSYS;
	117	return -1;
	118	}
	119	}
	120
	121	/* Do the real setgid */
	122	retval = plibc_func(gid);
	123	saved_errno = errno;
	124
d0c8f180	125	lttng_ust_after_setgid();
fca2f191 MJ	126
	127	errno = saved_errno;
	128	return retval;
	129	}
	130
	131	int seteuid(uid_t euid)
	132	{
	133	static int (*plibc_func)(uid_t euid) = NULL;
	134	int retval;
	135	int saved_errno;
	136
	137	if (plibc_func == NULL) {
	138	plibc_func = dlsym(RTLD_NEXT, "seteuid");
	139	if (plibc_func == NULL) {
	140	fprintf(stderr, "libustfork: unable to find \"seteuid\" symbol\n");
	141	errno = ENOSYS;
	142	return -1;
	143	}
	144	}
	145
	146	/* Do the real seteuid */
	147	retval = plibc_func(euid);
	148	saved_errno = errno;
	149
d0c8f180	150	lttng_ust_after_seteuid();
fca2f191 MJ	151
	152	errno = saved_errno;
	153	return retval;
	154	}
	155
	156	int setegid(gid_t egid)
	157	{
	158	static int (*plibc_func)(gid_t egid) = NULL;
	159	int retval;
	160	int saved_errno;
	161
	162	if (plibc_func == NULL) {
	163	plibc_func = dlsym(RTLD_NEXT, "setegid");
	164	if (plibc_func == NULL) {
	165	fprintf(stderr, "libustfork: unable to find \"setegid\" symbol\n");
	166	errno = ENOSYS;
	167	return -1;
	168	}
	169	}
	170
	171	/* Do the real setegid */
	172	retval = plibc_func(egid);
	173	saved_errno = errno;
	174
d0c8f180	175	lttng_ust_after_setegid();
fca2f191 MJ	176
	177	errno = saved_errno;
	178	return retval;
	179	}
	180
	181	int setreuid(uid_t ruid, uid_t euid)
	182	{
	183	static int (*plibc_func)(uid_t ruid, uid_t euid) = NULL;
	184	int retval;
	185	int saved_errno;
	186
	187	if (plibc_func == NULL) {
	188	plibc_func = dlsym(RTLD_NEXT, "setreuid");
	189	if (plibc_func == NULL) {
	190	fprintf(stderr, "libustfork: unable to find \"setreuid\" symbol\n");
	191	errno = ENOSYS;
	192	return -1;
	193	}
	194	}
	195
	196	/* Do the real setreuid */
	197	retval = plibc_func(ruid, euid);
	198	saved_errno = errno;
	199
d0c8f180	200	lttng_ust_after_setreuid();
fca2f191 MJ	201
	202	errno = saved_errno;
	203	return retval;
	204	}
	205
	206	int setregid(gid_t rgid, gid_t egid)
	207	{
	208	static int (*plibc_func)(gid_t rgid, gid_t egid) = NULL;
	209	int retval;
	210	int saved_errno;
	211
	212	if (plibc_func == NULL) {
	213	plibc_func = dlsym(RTLD_NEXT, "setregid");
	214	if (plibc_func == NULL) {
	215	fprintf(stderr, "libustfork: unable to find \"setregid\" symbol\n");
	216	errno = ENOSYS;
	217	return -1;
	218	}
	219	}
	220
	221	/* Do the real setregid */
	222	retval = plibc_func(rgid, egid);
	223	saved_errno = errno;
	224
d0c8f180	225	lttng_ust_after_setregid();
fca2f191 MJ	226
	227	errno = saved_errno;
	228	return retval;
	229	}
	230
939c89cb MD	231	#ifdef __linux__
	232
	233	struct user_desc;
	234
e822f505	235	struct ustfork_clone_info {
616ed36a PMF	236	int (fn)(void );
616ed36a PMF	237	void *arg;
7f0aeeba	238	sigset_t sigset;
616ed36a PMF	239	};
	240
	241	static int clone_fn(void *arg)
	242	{
e822f505	243	struct ustfork_clone_info info = (struct ustfork_clone_info ) arg;
616ed36a PMF	244
616ed36a PMF	245	/* clone is now done and we are in child */
d0c8f180	246	lttng_ust_after_fork_child(&info->sigset);
616ed36a PMF	247	return info->fn(info->arg);
	248	}
	249
	250	int clone(int (fn)(void ), void child_stack, int flags, void arg, ...)
	251	{
e822f505 MD	252	static int (plibc_func)(int (fn)(void ), void child_stack,
	253	int flags, void arg, pid_t ptid,
	254	struct user_desc tls, pid_t ctid) = NULL;
	255	/* var args */
616ed36a PMF	256	pid_t *ptid;
	257	struct user_desc *tls;
	258	pid_t *ctid;
e822f505	259	/* end of var args */
616ed36a	260	va_list ap;
e822f505	261	int retval;
111902ab	262	int saved_errno;
616ed36a PMF	263
	264	va_start(ap, arg);
	265	ptid = va_arg(ap, pid_t *);
	266	tls = va_arg(ap, struct user_desc *);
	267	ctid = va_arg(ap, pid_t *);
	268	va_end(ap);
	269
e822f505	270	if (plibc_func == NULL) {
616ed36a	271	plibc_func = dlsym(RTLD_NEXT, "clone");
e822f505 MD	272	if (plibc_func == NULL) {
e822f505 MD	273	fprintf(stderr, "libustfork: unable to find \"clone\" symbol.\n");
3678c8aa	274	errno = ENOSYS;
616ed36a PMF	275	return -1;
	276	}
	277	}
	278
e822f505 MD	279	if (flags & CLONE_VM) {
	280	/*
	281	* Creating a thread, no need to intervene, just pass on
	282	* the arguments.
	283	*/
	284	retval = plibc_func(fn, child_stack, flags, arg, ptid,
	285	tls, ctid);
111902ab	286	saved_errno = errno;
e822f505 MD	287	} else {
e822f505 MD	288	/* Creating a real process, we need to intervene. */
3fd2b913	289	struct ustfork_clone_info info = { .fn = fn, .arg = arg };
616ed36a	290
d0c8f180	291	lttng_ust_before_fork(&info.sigset);
e822f505 MD	292	retval = plibc_func(clone_fn, child_stack, flags, &info,
e822f505 MD	293	ptid, tls, ctid);
111902ab	294	saved_errno = errno;
e822f505	295	/* The child doesn't get here. */
d0c8f180	296	lttng_ust_after_fork_parent(&info.sigset);
616ed36a	297	}
111902ab	298	errno = saved_errno;
616ed36a PMF	299	return retval;
616ed36a PMF	300	}
939c89cb	301
735bef47 MJ	302	int setns(int fd, int nstype)
	303	{
	304	static int (*plibc_func)(int fd, int nstype) = NULL;
	305	int retval;
	306	int saved_errno;
	307
	308	if (plibc_func == NULL) {
	309	plibc_func = dlsym(RTLD_NEXT, "setns");
	310	if (plibc_func == NULL) {
	311	fprintf(stderr, "libustfork: unable to find \"setns\" symbol\n");
	312	errno = ENOSYS;
	313	return -1;
	314	}
	315	}
	316
	317	/* Do the real setns */
	318	retval = plibc_func(fd, nstype);
	319	saved_errno = errno;
	320
d0c8f180	321	lttng_ust_after_setns();
735bef47 MJ	322
	323	errno = saved_errno;
	324	return retval;
	325	}
	326
	327	int unshare(int flags)
	328	{
	329	static int (*plibc_func)(int flags) = NULL;
	330	int retval;
	331	int saved_errno;
	332
	333	if (plibc_func == NULL) {
	334	plibc_func = dlsym(RTLD_NEXT, "unshare");
	335	if (plibc_func == NULL) {
	336	fprintf(stderr, "libustfork: unable to find \"unshare\" symbol\n");
	337	errno = ENOSYS;
	338	return -1;
	339	}
	340	}
	341
	342	/* Do the real setns */
	343	retval = plibc_func(flags);
	344	saved_errno = errno;
	345
d0c8f180	346	lttng_ust_after_unshare();
735bef47 MJ	347
	348	errno = saved_errno;
	349	return retval;
	350	}
	351
fca2f191 MJ	352	int setresuid(uid_t ruid, uid_t euid, uid_t suid)
	353	{
	354	static int (*plibc_func)(uid_t ruid, uid_t euid, uid_t suid) = NULL;
	355	int retval;
	356	int saved_errno;
	357
	358	if (plibc_func == NULL) {
	359	plibc_func = dlsym(RTLD_NEXT, "setresuid");
	360	if (plibc_func == NULL) {
	361	fprintf(stderr, "libustfork: unable to find \"setresuid\" symbol\n");
	362	errno = ENOSYS;
	363	return -1;
	364	}
	365	}
	366
	367	/* Do the real setresuid */
	368	retval = plibc_func(ruid, euid, suid);
	369	saved_errno = errno;
	370
d0c8f180	371	lttng_ust_after_setresuid();
fca2f191 MJ	372
	373	errno = saved_errno;
	374	return retval;
	375	}
	376
	377	int setresgid(gid_t rgid, gid_t egid, gid_t sgid)
	378	{
	379	static int (*plibc_func)(gid_t rgid, gid_t egid, gid_t sgid) = NULL;
	380	int retval;
	381	int saved_errno;
	382
	383	if (plibc_func == NULL) {
	384	plibc_func = dlsym(RTLD_NEXT, "setresgid");
	385	if (plibc_func == NULL) {
	386	fprintf(stderr, "libustfork: unable to find \"setresgid\" symbol\n");
	387	errno = ENOSYS;
	388	return -1;
	389	}
	390	}
	391
	392	/* Do the real setresgid */
	393	retval = plibc_func(rgid, egid, sgid);
	394	saved_errno = errno;
	395
d0c8f180	396	lttng_ust_after_setresgid();
fca2f191 MJ	397
	398	errno = saved_errno;
	399	return retval;
	400	}
	401
939c89cb MD	402	#elif defined (__FreeBSD__)
	403
	404	pid_t rfork(int flags)
	405	{
	406	static pid_t (*plibc_func)(void) = NULL;
	407	sigset_t sigset;
	408	pid_t retval;
111902ab	409	int saved_errno;
939c89cb MD	410
	411	if (plibc_func == NULL) {
	412	plibc_func = dlsym(RTLD_NEXT, "rfork");
	413	if (plibc_func == NULL) {
	414	fprintf(stderr, "libustfork: unable to find \"rfork\" symbol\n");
3678c8aa	415	errno = ENOSYS;
939c89cb MD	416	return -1;
	417	}
	418	}
	419
d0c8f180	420	lttng_ust_before_fork(&sigset);
939c89cb MD	421	/* Do the real rfork */
939c89cb MD	422	retval = plibc_func();
111902ab	423	saved_errno = errno;
939c89cb MD	424	if (retval == 0) {
939c89cb MD	425	/* child */
d0c8f180	426	lttng_ust_after_fork_child(&sigset);
939c89cb	427	} else {
d0c8f180	428	lttng_ust_after_fork_parent(&sigset);
939c89cb	429	}
111902ab	430	errno = saved_errno;
939c89cb MD	431	return retval;
	432	}
	433
	434	/*
	435	* On BSD, no need to override vfork, because it runs in the context of
	436	* the parent, with parent waiting until execve or exit is executed in
	437	* the child.
	438	*/
	439
	440	#else
	441	#warning "Unknown OS. You might want to ensure that fork/clone/vfork/fork handling is complete."
	442	#endif