less: switch off nonblock on kbd_fd before exit
authorDenys Vlasenko <vda.linux@googlemail.com>
Tue, 13 Sep 2016 19:05:48 +0000 (21:05 +0200)
committerDenys Vlasenko <vda.linux@googlemail.com>
Tue, 13 Sep 2016 19:05:48 +0000 (21:05 +0200)
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>
miscutils/less.c

index 877ab6ef2c2fadf8be6d6de1da4573cb408b8275..61acfdcb5045c06ae69b885f9c8d78f73c6dce6a 100644 (file)
@@ -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);