1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_TTY_FLIP_H
3 #define _LINUX_TTY_FLIP_H
4 
5 #include <linux/tty_buffer.h>
6 #include <linux/tty_port.h>
7 
8 struct tty_ldisc;
9 
10 int tty_buffer_set_limit(struct tty_port *port, int limit);
11 unsigned int tty_buffer_space_avail(struct tty_port *port);
12 int tty_buffer_request_room(struct tty_port *port, size_t size);
13 size_t __tty_insert_flip_string_flags(struct tty_port *port, const u8 *chars,
14 				      const u8 *flags, bool mutable_flags,
15 				      size_t size);
16 size_t tty_prepare_flip_string(struct tty_port *port, u8 **chars, size_t size);
17 void tty_flip_buffer_push(struct tty_port *port);
18 
19 /**
20  * tty_insert_flip_string_fixed_flag - add characters to the tty buffer
21  * @port: tty port
22  * @chars: characters
23  * @flag: flag value for each character
24  * @size: size
25  *
26  * Queue a series of bytes to the tty buffering. All the characters passed are
27  * marked with the supplied flag.
28  *
29  * Returns: the number added.
30  */
tty_insert_flip_string_fixed_flag(struct tty_port * port,const u8 * chars,u8 flag,size_t size)31 static inline size_t tty_insert_flip_string_fixed_flag(struct tty_port *port,
32 						       const u8 *chars, u8 flag,
33 						       size_t size)
34 {
35 	return __tty_insert_flip_string_flags(port, chars, &flag, false, size);
36 }
37 
38 /**
39  * tty_insert_flip_string_flags - add characters to the tty buffer
40  * @port: tty port
41  * @chars: characters
42  * @flags: flag bytes
43  * @size: size
44  *
45  * Queue a series of bytes to the tty buffering. For each character the flags
46  * array indicates the status of the character.
47  *
48  * Returns: the number added.
49  */
tty_insert_flip_string_flags(struct tty_port * port,const u8 * chars,const u8 * flags,size_t size)50 static inline size_t tty_insert_flip_string_flags(struct tty_port *port,
51 						  const u8 *chars,
52 						  const u8 *flags, size_t size)
53 {
54 	return __tty_insert_flip_string_flags(port, chars, flags, true, size);
55 }
56 
57 /**
58  * tty_insert_flip_char - add one character to the tty buffer
59  * @port: tty port
60  * @ch: character
61  * @flag: flag byte
62  *
63  * Queue a single byte @ch to the tty buffering, with an optional flag.
64  */
tty_insert_flip_char(struct tty_port * port,u8 ch,u8 flag)65 static inline size_t tty_insert_flip_char(struct tty_port *port, u8 ch, u8 flag)
66 {
67 	struct tty_buffer *tb = port->buf.tail;
68 	int change;
69 
70 	change = !tb->flags && (flag != TTY_NORMAL);
71 	if (!change && tb->used < tb->size) {
72 		if (tb->flags)
73 			*flag_buf_ptr(tb, tb->used) = flag;
74 		*char_buf_ptr(tb, tb->used++) = ch;
75 		return 1;
76 	}
77 	return __tty_insert_flip_string_flags(port, &ch, &flag, false, 1);
78 }
79 
tty_insert_flip_string(struct tty_port * port,const u8 * chars,size_t size)80 static inline size_t tty_insert_flip_string(struct tty_port *port,
81 					    const u8 *chars, size_t size)
82 {
83 	return tty_insert_flip_string_fixed_flag(port, chars, TTY_NORMAL, size);
84 }
85 
86 size_t tty_ldisc_receive_buf(struct tty_ldisc *ld, const u8 *p, const u8 *f,
87 			     size_t count);
88 
89 void tty_buffer_lock_exclusive(struct tty_port *port);
90 void tty_buffer_unlock_exclusive(struct tty_port *port);
91 
92 #endif /* _LINUX_TTY_FLIP_H */
93