[PATCH] constify tty flip buffer handling

Add a couple of 'const' qualifiers to the TTY flip buffer APIs, where
appropriate.

Signed-off-by: Thomas Koeller <[e-mail]>
Acked-by: Alan Cox <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

drivers/char/tty_io.c

···
 
 EXPORT_SYMBOL_GPL(tty_buffer_request_room);
 
-int tty_insert_flip_string(struct tty_struct *tty, unsigned char *chars, size_t size)
+int tty_insert_flip_string(struct tty_struct *tty, const unsigned char *chars, size_t size)
 {
 	int copied = 0;
 	do {
···
 
 EXPORT_SYMBOL_GPL(tty_insert_flip_string);
 
-int tty_insert_flip_string_flags(struct tty_struct *tty, unsigned char *chars, char *flags, size_t size)
+int tty_insert_flip_string_flags(struct tty_struct *tty, const unsigned char *chars, const char *flags, size_t size)
 {
 	int copied = 0;
 	do {

include/linux/tty_flip.h

···
 #define _LINUX_TTY_FLIP_H
 
 extern int tty_buffer_request_room(struct tty_struct *tty, size_t size);
-extern int tty_insert_flip_string(struct tty_struct *tty, unsigned char *chars, size_t size);
-extern int tty_insert_flip_string_flags(struct tty_struct *tty, unsigned char *chars, char *flags, size_t size);
+extern int tty_insert_flip_string(struct tty_struct *tty, const unsigned char *chars, size_t size);
+extern int tty_insert_flip_string_flags(struct tty_struct *tty, const unsigned char *chars, const char *flags, size_t size);
 extern int tty_prepare_flip_string(struct tty_struct *tty, unsigned char **chars, size_t size);
 extern int tty_prepare_flip_string_flags(struct tty_struct *tty, unsigned char **chars, char **flags, size_t size);