less: switch off nonblock on kbd_fd before exit

This is only necessary if we use stdout fd.

function                                             old     new   delta
less_exit                                             32      51     +19
less_main                                           2540    2543      +3
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 2/0 up/down: 22/0)               Total: 22 bytes

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

1 files changed, 5 insertions, 7 deletions

diff --git a/miscutils/less.c b/miscutils/less.c
index 877ab6ef2..61acfdcb5 100644
--- a/miscutils/less.c
+++ b/miscutils/less.c
@@ -169,6 +169,7 @@ enum { pattern_valid = 0 };
 struct globals {
         int cur_fline; /* signed */
         int kbd_fd;  /* fd to get input from */
+        int kbd_fd_orig_flags;
         int less_gets_pos;
 /* last position in last line, taking into account tabs */
         size_t last_line_pos;
@@ -304,6 +305,8 @@ static void print_statusline(const char *str)
 static void less_exit(int code)
 {
         set_tty_cooked();
+        if (!(G.kbd_fd_orig_flags & O_NONBLOCK))
+                ndelay_off(kbd_fd);
         clear_line();
         if (code < 0)
                 kill_myself_with_sig(- code); /* does not return */
@@ -1813,16 +1816,11 @@ int less_main(int argc, char **argv)
  try_ctty:
                 tty_fd = open(CURRENT_TTY, O_RDONLY);
                 if (tty_fd < 0) {
-                        /*
-                         * If all else fails, less 481 uses stdout. Mimic that.
-                         * Testcase where usually both ttyname(STDOUT_FILENO)
-                         * and open(CURRENT_TTY) fail:
-                         * su -s /bin/sh -c 'busybox less FILE' - nobody
-                         */
+                        /* If all else fails, less 481 uses stdout. Mimic that */
                         tty_fd = STDOUT_FILENO;
                 }
         }
-        ndelay_on(tty_fd);
+        G.kbd_fd_orig_flags = ndelay_on(tty_fd);
         kbd_fd = tty_fd; /* save in a global */
 
         tcgetattr(kbd_fd, &term_orig);