support/kconfig: handle backspace (^H) key

This is in the mainline kernel since v5.1-rc3:
9c38f1f04408 ("kconfig/[mn]conf: handle backspace (^H) key")

Quoting the commit's log:

"
Backspace is not working on some terminal emulators which do not send the
key code defined by terminfo. Terminals either send '^H' (8) or '^?' (127).
But currently only '^?' is handled. Let's also handle '^H' for those
terminals.
"

Signed-off-by: Sébastien Szymanski <sebastien.szymanski@armadeus.com>
Signed-off-by: Julien Olivain <ju.o@free.fr>
(cherry picked from commit d65c10c20add58f17cf1d7b6de8e7903b0aa9ddc)

support/kconfig/lxdialog/inputbox.c

@@ -126,7 +126,8 @@ do_resize:
 			case KEY_DOWN:
 				break;
 			case KEY_BACKSPACE:
-			case 127:
+			case 8:   /* ^H */
+			case 127: /* ^? */
 				if (pos) {
 					wattrset(dialog, dlg.inputbox.atr);
 					if (input_x == 0) {

support/kconfig/nconf.c

@@ -1048,7 +1048,7 @@ static int do_match(int key, struct match_state *state, int *ans)
 		state->match_direction = FIND_NEXT_MATCH_UP;
 		*ans = get_mext_match(state->pattern,
 				state->match_direction);
-	} else if (key == KEY_BACKSPACE || key == 127) {
+	} else if (key == KEY_BACKSPACE || key == 8 || key == 127) {
 		state->pattern[strlen(state->pattern)-1] = '\0';
 		adj_match_dir(&state->match_direction);
 	} else

support/kconfig/nconf.gui.c

@@ -440,7 +440,8 @@ int dialog_inputbox(WINDOW *main_window,
 		case KEY_F(F_EXIT):
 		case KEY_F(F_BACK):
 			break;
-		case 127:
+		case 8:   /* ^H */
+		case 127: /* ^? */
 		case KEY_BACKSPACE:
 			if (cursor_position > 0) {
 				memmove(&result[cursor_position-1],

support/kconfig/patches/23-kconfig-mn-conf-handle-backspace-H-key.patch

@@ -0,0 +1,62 @@
+From 9c38f1f044080392603c497ecca4d7d09876ff99 Mon Sep 17 00:00:00 2001
+From: Changbin Du <changbin.du@gmail.com>
+Date: Mon, 25 Mar 2019 15:16:47 +0000
+Subject: [PATCH 23/23] kconfig/[mn]conf: handle backspace (^H) key
+
+Backspace is not working on some terminal emulators which do not send the
+key code defined by terminfo. Terminals either send '^H' (8) or '^?' (127).
+But currently only '^?' is handled. Let's also handle '^H' for those
+terminals.
+
+Signed-off-by: Changbin Du <changbin.du@gmail.com>
+Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
+---
+ kconfig/lxdialog/inputbox.c | 3 ++-
+ kconfig/nconf.c             | 2 +-
+ kconfig/nconf.gui.c         | 3 ++-
+ 3 files changed, 5 insertions(+), 3 deletions(-)
+
+diff --git a/kconfig/lxdialog/inputbox.c b/kconfig/lxdialog/inputbox.c
+index 611945611bf8..1dcfb288ee63 100644
+--- a/kconfig/lxdialog/inputbox.c
++++ b/kconfig/lxdialog/inputbox.c
+@@ -113,7 +113,8 @@ int dialog_inputbox(const char *title, const char *prompt, int height, int width
+ 			case KEY_DOWN:
+ 				break;
+ 			case KEY_BACKSPACE:
+-			case 127:
++			case 8:   /* ^H */
++			case 127: /* ^? */
+ 				if (pos) {
+ 					wattrset(dialog, dlg.inputbox.atr);
+ 					if (input_x == 0) {
+diff --git a/kconfig/nconf.c b/kconfig/nconf.c
+index a4670f4e825a..ac92c0ded6c5 100644
+--- a/kconfig/nconf.c
++++ b/kconfig/nconf.c
+@@ -1048,7 +1048,7 @@ static int do_match(int key, struct match_state *state, int *ans)
+ 		state->match_direction = FIND_NEXT_MATCH_UP;
+ 		*ans = get_mext_match(state->pattern,
+ 				state->match_direction);
+-	} else if (key == KEY_BACKSPACE || key == 127) {
++	} else if (key == KEY_BACKSPACE || key == 8 || key == 127) {
+ 		state->pattern[strlen(state->pattern)-1] = '\0';
+ 		adj_match_dir(&state->match_direction);
+ 	} else
+diff --git a/kconfig/nconf.gui.c b/kconfig/nconf.gui.c
+index 7be620a1fcdb..77f525a8617c 100644
+--- a/kconfig/nconf.gui.c
++++ b/kconfig/nconf.gui.c
+@@ -439,7 +439,8 @@ int dialog_inputbox(WINDOW *main_window,
+ 		case KEY_F(F_EXIT):
+ 		case KEY_F(F_BACK):
+ 			break;
+-		case 127:
++		case 8:   /* ^H */
++		case 127: /* ^? */
+ 		case KEY_BACKSPACE:
+ 			if (cursor_position > 0) {
+ 				memmove(&result[cursor_position-1],
+-- 
+2.48.1
+

support/kconfig/patches/series

@@ -11,3 +11,4 @@
 20-merge_config.sh-Allow-to-define-config-prefix.patch
 21-Avoid-false-positive-matches-from-comment-lines.patch
 22-kconfig-lxdialog-fix-check-with-GCC14.patch
+23-kconfig-mn-conf-handle-backspace-H-key.patch