[PATCH v2] common: cli_hush: terminate all commands when Ctrl-C is pressed

[Shiji Yang]

Check Ctrl-C status before executing each command in the pipeline so
that the Ctrl-C can skip all subsequent commands. in the meantime, we
need to clear the ctrlc status at the end of a pipeline. This should
be the default behavior of most shell parsers.

Before the change:
```
=> echo start; while true; do echo loop; sleep 1; done; echo int; if true; then echo if; fi; echo stop
start
loop
loop	<-- Input Ctrl-C
int
if
stop
=>
```
After the change:
```
=> echo start; while true; do echo loop; sleep 1; done; echo int; if true; then echo if; fi; echo stop
start
loop
loop	<-- Input Ctrl-C
^C
=>
```

Signed-off-by: Shiji Yang <yangshiji66 at outlook.com>
---
v1 --> v2:
 - use puts() instead of printf()
 - only clear Ctrl-C status when one pipe reaches the end

 common/cli_hush.c | 20 ++++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

diff --git a/common/cli_hush.c b/common/cli_hush.c
index 7bd6943d3ed..3f6adc01934 100644
--- a/common/cli_hush.c
+++ b/common/cli_hush.c
@@ -1792,16 +1792,15 @@ static int run_list_real(struct pipe *pi)
 		}
 	}
 	for (; pi; pi = (flag_restore != 0) ? rpipe : pi->next) {
-		if (pi->r_mode == RES_WHILE || pi->r_mode == RES_UNTIL ||
-			pi->r_mode == RES_FOR) {
 #ifdef __U_BOOT__
-				/* check Ctrl-C */
-				ctrlc();
-				if ((had_ctrlc())) {
-					return 1;
-				}
+		/* check Ctrl-C */
+		ctrlc();
+		if (had_ctrlc())
+			return 1;
 #endif
-				flag_restore = 0;
+		if (pi->r_mode == RES_WHILE || pi->r_mode == RES_UNTIL ||
+		    pi->r_mode == RES_FOR) {
+			flag_restore = 0;
 				if (!rpipe) {
 					flag_rep = 0;
 					rpipe = pi;
@@ -3207,6 +3206,11 @@ static int parse_stream_outer(struct in_str *inp, int flag)
 			run_list(ctx.list_head);
 #else
 			code = run_list(ctx.list_head);
+			/* clear Ctrl-C status when one pipe reaches the end */
+			if (had_ctrlc() && !(flag & FLAG_REPARSING)) {
+				puts("^C\n");
+				clear_ctrlc();
+			}
 			if (code == -2) {	/* exit */
 				b_free(&temp);
 				code = 0;
-- 
2.51.0