ash: fixes to handling of ctrl-C in read builtin

Consider this script:

   while read -r; do echo $REPLY; done
   echo hello

There are currently two problems with this when the read is interrupted
by ctrl-C:

- The error return code is 0 when it should be 130;
- The echo command is executed.

Fix these issues by propagating the control event to the process that
would have caught it if the read builtin hadn't grabbed keyboard input.

1 files changed, 7 insertions, 2 deletions

diff --git a/shell/shell_common.c b/shell/shell_common.c
index 320cd88fd..9092a8e2b 100644
--- a/shell/shell_common.c
+++ b/shell/shell_common.c
@@ -235,8 +235,13 @@ shell_builtin_read(struct builtin_read_params *params)
                         int64_t key;
 
                         key = read_key(fd, NULL, timeout);
-                        if (key == 0x03 || key == -1 || (key == 0x1a && bufpos == 0)) {
-                                /* ^C, timeout or ^Z at start of buffer */
+                        if (key == 0x03) {
+                                /* ^C pressed */
+                                retval = (const char *)(uintptr_t)2;
+                                goto ret;
+                        }
+                        else if (key == -1 || (key == 0x1a && bufpos == 0)) {
+                                /* timeout or ^Z at start of buffer */
                                 retval = (const char *)(uintptr_t)1;
                                 goto ret;
                         }