[git commit branch/1_36_stable] ash: fix sleep built-in not running INT trap immediately on ^C

[Denys Vlasenko]

commit: https://git.busybox.net/busybox/commit/?id=ce839dea92ce10627094096835e831bf5d267631
branch: https://git.busybox.net/busybox/commit/?id=refs/heads/1_36_stable

function                                             old     new   delta
sleep_for_duration                                   169     149     -20

Signed-off-by: Denys Vlasenko <vda.linux at googlemail.com>
---
 libbb/duration.c | 16 +++++++---------
 1 file changed, 7 insertions(+), 9 deletions(-)

diff --git a/libbb/duration.c b/libbb/duration.c
index 793d02f42..0024f1a66 100644
--- a/libbb/duration.c
+++ b/libbb/duration.c
@@ -76,16 +76,14 @@ void FAST_FUNC sleep_for_duration(duration_t duration)
 		ts.tv_sec = duration;
 		ts.tv_nsec = (duration - ts.tv_sec) * 1000000000;
 	}
-	/* NB: if ENABLE_ASH_SLEEP, we end up here if "sleep N"
-	 * is run in ash. ^C will still work, because ash's signal handler
-	 * does not return (it longjumps), the below loop
-	 * will not continue looping.
-	 * (This wouldn't work in hush)
+	/* NB: ENABLE_ASH_SLEEP requires that we do NOT loop on EINTR here:
+	 * otherwise, traps won't execute until we finish looping.
 	 */
-	do {
-		errno = 0;
-		nanosleep(&ts, &ts);
-	} while (errno == EINTR);
+	//do {
+	//	errno = 0;
+	//	nanosleep(&ts, &ts);
+	//} while (errno == EINTR);
+	nanosleep(&ts, &ts);
 }
 #else
 duration_t FAST_FUNC parse_duration_str(char *str)