Fix known issues which blow up the process after dlopen("libthr.so")

(or loading a dso linked to libthr.so into process which was not
linked against threading library).

MFC r276630:
Remove interposing, fix malloc, reinstall signal handlers wrappers on
libthr load.

MFC r276681:
Avoid calling internal libc function through PLT or accessing data
though GOT.

MFC r277032:
Reduce the size of the interposing table and amount of
cancellation-handling code in the libthr.

MFC note:
r276646 ("do not erronously export 'openat' symbol from rtld") is not
applicable to stable/10 yet, since PATHFDS support was not merged.

1 files changed, 4 insertions, 1 deletions

diff --git a/lib/libc/gen/usleep.c b/lib/libc/gen/usleep.c
index 7d6559b..7c35f6c 100644
--- a/lib/libc/gen/usleep.c
+++ b/lib/libc/gen/usleep.c
@@ -38,6 +38,8 @@ __FBSDID("$FreeBSD$");
 #include <unistd.h>
 #include "un-namespace.h"
 
+#include "libc_private.h"
+
 int
 __usleep(useconds_t useconds)
 {
@@ -45,7 +47,8 @@ __usleep(useconds_t useconds)
 
 	time_to_sleep.tv_nsec = (useconds % 1000000) * 1000;
 	time_to_sleep.tv_sec = useconds / 1000000;
-	return (_nanosleep(&time_to_sleep, NULL));
+	return (((int (*)(const struct timespec *, struct timespec *))
+	    __libc_interposing[INTERPOS_nanosleep])(&time_to_sleep, NULL));
 }
 
 __weak_reference(__usleep, usleep);