upstream: In the editline(3) branch of the sftp(1) event loop,

handle SIGINT rather than ignoring it, such that the user can use Ctrl-C to
discard the currently edited command line and get a fresh prompt, just like
in ftp(1), bc(1), and in shells.

It is critical to not use ssl_signal() for this particular case
because that function unconditionally sets SA_RESTART, but here we
need the signal to interrupt the read(2) in the el_gets(3) event loop.

OK dtucker@ deraadt@

OpenBSD-Commit-ID: 8025115a773f52e9bb562eaab37ea2e021cc7299

1 files changed, 20 insertions, 4 deletions

diff --git a/sftp.c b/sftp.c
index 95b2e0b7c..69f84cdcf 100644
--- a/sftp.c
+++ b/sftp.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: sftp.c,v 1.210 2021/08/07 00:12:09 djm Exp $ */
+/* $OpenBSD: sftp.c,v 1.211 2021/08/12 09:59:00 schwarze Exp $ */
 /*
  * Copyright (c) 2001-2004 Damien Miller <djm@openbsd.org>
  *
@@ -252,6 +252,13 @@ cmd_interrupt(int signo)
 	errno = olderrno;
 }
 
+/* ARGSUSED */
+static void
+read_interrupt(int signo)
+{
+	interrupted = 1;
+}
+
 /*ARGSUSED*/
 static void
 sigchld_handler(int sig)
@@ -2197,8 +2204,6 @@ interactive_loop(struct sftp_conn *conn, char *file1, char *file2)
 	interactive = !batchmode && isatty(STDIN_FILENO);
 	err = 0;
 	for (;;) {
-		ssh_signal(SIGINT, SIG_IGN);
-
 		if (el == NULL) {
 			if (interactive)
 				printf("sftp> ");
@@ -2211,10 +2216,21 @@ interactive_loop(struct sftp_conn *conn, char *file1, char *file2)
 #ifdef USE_LIBEDIT
 			const char *line;
 			int count = 0;
-
+			struct sigaction sa;
+
+			interrupted = 0;
+			memset(&sa, 0, sizeof(sa));
+			sa.sa_handler = read_interrupt;
+			if (sigaction(SIGINT, &sa, NULL) == -1) {
+				debug3("sigaction(%s): %s",
+				    strsignal(SIGINT), strerror(errno));
+				break;
+			}
 			if ((line = el_gets(el, &count)) == NULL ||
 			    count <= 0) {
 				printf("\n");
+				if (interrupted)
+					continue;
 				break;
 			}
 			history(hl, &hev, H_ENTER, line);