tty: constify return type of tty_name

All users of tty_name pass the result directly to a printf-like
function. This means we can actually let tty_name return the literal
"NULL tty" or tty->name directly, avoiding the strcpy and a lot of
medium-sized stack buffers. In preparation for that, make the return
type const char*.

While at it, we can also constify the tty parameter.

Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Rasmus Villemoes 2015-03-31 15:55:57 +02:00 committed by Greg Kroah-Hartman
parent caec172d57
commit 1d6b98774c
2 changed files with 2 additions and 2 deletions

View File

@ -243,7 +243,7 @@ static void tty_del_file(struct file *file)
* Locking: none
*/
char *tty_name(struct tty_struct *tty, char *buf)
const char *tty_name(const struct tty_struct *tty, char *buf)
{
if (!tty) /* Hmm. NULL pointer. That's fun. */
strcpy(buf, "NULL tty");

View File

@ -421,7 +421,7 @@ static inline struct tty_struct *tty_kref_get(struct tty_struct *tty)
extern int tty_paranoia_check(struct tty_struct *tty, struct inode *inode,
const char *routine);
extern char *tty_name(struct tty_struct *tty, char *buf);
extern const char *tty_name(const struct tty_struct *tty, char *buf);
extern void tty_wait_until_sent(struct tty_struct *tty, long timeout);
extern int tty_check_change(struct tty_struct *tty);
extern void __stop_tty(struct tty_struct *tty);