ash: allow "trap NUM [SIG]..." syntax

While at it, make get_signum() return -1 for numeric strings >= NSIG.

function                                             old     new   delta
trapcmd                                              292     306     +14
get_signum                                           295     300      +5
builtin_trap                                         413     412      -1
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/1 up/down: 19/-1)              Total: 18 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/shell/hush.c b/shell/hush.c
index f9dad074f..11b33f40a 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -9745,7 +9745,7 @@ static int FAST_FUNC builtin_trap(char **argv)
 			sighandler_t handler;
 
 			sig = get_signum(*argv++);
-			if (sig < 0 || sig >= NSIG) {
+			if (sig < 0) {
 				ret = EXIT_FAILURE;
 				/* Mimic bash message exactly */
 				bb_error_msg("trap: %s: invalid signal specification", argv[-1]);