2 * linux/drivers/char/tty_ioctl.c
4 * Copyright (C) 1991, 1992, 1993, 1994 Linus Torvalds
6 * Modified by Fred N. van Kempen, 01/29/93, to add line disciplines
7 * which can be dynamically activated and de-activated by the line
8 * discipline handling modules (like SLIP).
11 #include <linux/types.h>
12 #include <linux/termios.h>
13 #include <linux/errno.h>
14 #include <linux/sched.h>
15 #include <linux/kernel.h>
16 #include <linux/major.h>
17 #include <linux/tty.h>
18 #include <linux/fcntl.h>
19 #include <linux/string.h>
21 #include <linux/module.h>
24 #include <asm/bitops.h>
25 #include <asm/uaccess.h>
26 #include <asm/system.h>
28 #undef TTY_DEBUG_WAIT_UNTIL_SENT
33 * Internal flag options for termios setting behavior
35 #define TERMIOS_FLUSH 1
36 #define TERMIOS_WAIT 2
37 #define TERMIOS_TERMIO 4
39 void tty_wait_until_sent(struct tty_struct * tty, long timeout)
41 DECLARE_WAITQUEUE(wait, current);
43 #ifdef TTY_DEBUG_WAIT_UNTIL_SENT
46 printk(KERN_DEBUG "%s wait until sent...\n", tty_name(tty, buf));
48 if (!tty->driver->chars_in_buffer)
50 add_wait_queue(&tty->write_wait, &wait);
52 timeout = MAX_SCHEDULE_TIMEOUT;
54 #ifdef TTY_DEBUG_WAIT_UNTIL_SENT
55 printk(KERN_DEBUG "waiting %s...(%d)\n", tty_name(tty, buf),
56 tty->driver->chars_in_buffer(tty));
58 set_current_state(TASK_INTERRUPTIBLE);
59 if (signal_pending(current))
61 if (!tty->driver->chars_in_buffer(tty))
63 timeout = schedule_timeout(timeout);
65 if (tty->driver->wait_until_sent)
66 tty->driver->wait_until_sent(tty, timeout);
68 set_current_state(TASK_RUNNING);
69 remove_wait_queue(&tty->write_wait, &wait);
72 EXPORT_SYMBOL(tty_wait_until_sent);
74 static void unset_locked_termios(struct termios *termios,
76 struct termios *locked)
80 #define NOSET_MASK(x,y,z) (x = ((x) & ~(z)) | ((y) & (z)))
83 printk(KERN_WARNING "Warning?!? termios_locked is NULL.\n");
87 NOSET_MASK(termios->c_iflag, old->c_iflag, locked->c_iflag);
88 NOSET_MASK(termios->c_oflag, old->c_oflag, locked->c_oflag);
89 NOSET_MASK(termios->c_cflag, old->c_cflag, locked->c_cflag);
90 NOSET_MASK(termios->c_lflag, old->c_lflag, locked->c_lflag);
91 termios->c_line = locked->c_line ? old->c_line : termios->c_line;
92 for (i=0; i < NCCS; i++)
93 termios->c_cc[i] = locked->c_cc[i] ?
94 old->c_cc[i] : termios->c_cc[i];
97 static void change_termios(struct tty_struct * tty, struct termios * new_termios)
100 struct termios old_termios = *tty->termios;
102 local_irq_disable(); // FIXME: is this safe?
103 *tty->termios = *new_termios;
104 unset_locked_termios(tty->termios, &old_termios, tty->termios_locked);
105 canon_change = (old_termios.c_lflag ^ tty->termios->c_lflag) & ICANON;
107 memset(&tty->read_flags, 0, sizeof tty->read_flags);
108 tty->canon_head = tty->read_tail;
112 local_irq_enable(); // FIXME: is this safe?
113 if (canon_change && !L_ICANON(tty) && tty->read_cnt)
114 /* Get characters left over from canonical mode. */
115 wake_up_interruptible(&tty->read_wait);
117 /* see if packet mode change of state */
119 if (tty->link && tty->link->packet) {
120 int old_flow = ((old_termios.c_iflag & IXON) &&
121 (old_termios.c_cc[VSTOP] == '\023') &&
122 (old_termios.c_cc[VSTART] == '\021'));
123 int new_flow = (I_IXON(tty) &&
124 STOP_CHAR(tty) == '\023' &&
125 START_CHAR(tty) == '\021');
126 if (old_flow != new_flow) {
127 tty->ctrl_status &= ~(TIOCPKT_DOSTOP | TIOCPKT_NOSTOP);
129 tty->ctrl_status |= TIOCPKT_DOSTOP;
131 tty->ctrl_status |= TIOCPKT_NOSTOP;
132 wake_up_interruptible(&tty->link->read_wait);
136 if (tty->driver->set_termios)
137 (*tty->driver->set_termios)(tty, &old_termios);
139 if (tty->ldisc.set_termios)
140 (*tty->ldisc.set_termios)(tty, &old_termios);
143 static int set_termios(struct tty_struct * tty, void __user *arg, int opt)
145 struct termios tmp_termios;
146 int retval = tty_check_change(tty);
151 if (opt & TERMIOS_TERMIO) {
152 memcpy(&tmp_termios, tty->termios, sizeof(struct termios));
153 if (user_termio_to_kernel_termios(&tmp_termios,
154 (struct termio __user *)arg))
157 if (user_termios_to_kernel_termios(&tmp_termios,
158 (struct termios __user *)arg))
162 if ((opt & TERMIOS_FLUSH) && tty->ldisc.flush_buffer)
163 tty->ldisc.flush_buffer(tty);
165 if (opt & TERMIOS_WAIT) {
166 tty_wait_until_sent(tty, 0);
167 if (signal_pending(current))
171 change_termios(tty, &tmp_termios);
175 static int get_termio(struct tty_struct * tty, struct termio __user * termio)
177 if (kernel_termios_to_user_termio(termio, tty->termios))
182 static unsigned long inq_canon(struct tty_struct * tty)
186 if (!tty->canon_data || !tty->read_buf)
188 head = tty->canon_head;
189 tail = tty->read_tail;
190 nr = (head - tail) & (N_TTY_BUF_SIZE-1);
191 /* Skip EOF-chars.. */
192 while (head != tail) {
193 if (test_bit(tail, tty->read_flags) &&
194 tty->read_buf[tail] == __DISABLED_CHAR)
196 tail = (tail+1) & (N_TTY_BUF_SIZE-1);
203 * These are deprecated, but there is limited support..
205 * The "sg_flags" translation is a joke..
207 static int get_sgflags(struct tty_struct * tty)
211 if (!(tty->termios->c_lflag & ICANON)) {
212 if (tty->termios->c_lflag & ISIG)
213 flags |= 0x02; /* cbreak */
215 flags |= 0x20; /* raw */
217 if (tty->termios->c_lflag & ECHO)
218 flags |= 0x08; /* echo */
219 if (tty->termios->c_oflag & OPOST)
220 if (tty->termios->c_oflag & ONLCR)
221 flags |= 0x10; /* crmod */
225 static int get_sgttyb(struct tty_struct * tty, struct sgttyb __user * sgttyb)
231 tmp.sg_erase = tty->termios->c_cc[VERASE];
232 tmp.sg_kill = tty->termios->c_cc[VKILL];
233 tmp.sg_flags = get_sgflags(tty);
234 return copy_to_user(sgttyb, &tmp, sizeof(tmp)) ? -EFAULT : 0;
237 static void set_sgflags(struct termios * termios, int flags)
239 termios->c_iflag = ICRNL | IXON;
240 termios->c_oflag = 0;
241 termios->c_lflag = ISIG | ICANON;
242 if (flags & 0x02) { /* cbreak */
243 termios->c_iflag = 0;
244 termios->c_lflag &= ~ICANON;
246 if (flags & 0x08) { /* echo */
247 termios->c_lflag |= ECHO | ECHOE | ECHOK |
248 ECHOCTL | ECHOKE | IEXTEN;
250 if (flags & 0x10) { /* crmod */
251 termios->c_oflag |= OPOST | ONLCR;
253 if (flags & 0x20) { /* raw */
254 termios->c_iflag = 0;
255 termios->c_lflag &= ~(ISIG | ICANON);
257 if (!(termios->c_lflag & ICANON)) {
258 termios->c_cc[VMIN] = 1;
259 termios->c_cc[VTIME] = 0;
263 static int set_sgttyb(struct tty_struct * tty, struct sgttyb __user * sgttyb)
267 struct termios termios;
269 retval = tty_check_change(tty);
272 termios = *tty->termios;
273 if (copy_from_user(&tmp, sgttyb, sizeof(tmp)))
275 termios.c_cc[VERASE] = tmp.sg_erase;
276 termios.c_cc[VKILL] = tmp.sg_kill;
277 set_sgflags(&termios, tmp.sg_flags);
278 change_termios(tty, &termios);
284 static int get_tchars(struct tty_struct * tty, struct tchars __user * tchars)
288 tmp.t_intrc = tty->termios->c_cc[VINTR];
289 tmp.t_quitc = tty->termios->c_cc[VQUIT];
290 tmp.t_startc = tty->termios->c_cc[VSTART];
291 tmp.t_stopc = tty->termios->c_cc[VSTOP];
292 tmp.t_eofc = tty->termios->c_cc[VEOF];
293 tmp.t_brkc = tty->termios->c_cc[VEOL2]; /* what is brkc anyway? */
294 return copy_to_user(tchars, &tmp, sizeof(tmp)) ? -EFAULT : 0;
297 static int set_tchars(struct tty_struct * tty, struct tchars __user * tchars)
301 if (copy_from_user(&tmp, tchars, sizeof(tmp)))
303 tty->termios->c_cc[VINTR] = tmp.t_intrc;
304 tty->termios->c_cc[VQUIT] = tmp.t_quitc;
305 tty->termios->c_cc[VSTART] = tmp.t_startc;
306 tty->termios->c_cc[VSTOP] = tmp.t_stopc;
307 tty->termios->c_cc[VEOF] = tmp.t_eofc;
308 tty->termios->c_cc[VEOL2] = tmp.t_brkc; /* what is brkc anyway? */
314 static int get_ltchars(struct tty_struct * tty, struct ltchars __user * ltchars)
318 tmp.t_suspc = tty->termios->c_cc[VSUSP];
319 tmp.t_dsuspc = tty->termios->c_cc[VSUSP]; /* what is dsuspc anyway? */
320 tmp.t_rprntc = tty->termios->c_cc[VREPRINT];
321 tmp.t_flushc = tty->termios->c_cc[VEOL2]; /* what is flushc anyway? */
322 tmp.t_werasc = tty->termios->c_cc[VWERASE];
323 tmp.t_lnextc = tty->termios->c_cc[VLNEXT];
324 return copy_to_user(ltchars, &tmp, sizeof(tmp)) ? -EFAULT : 0;
327 static int set_ltchars(struct tty_struct * tty, struct ltchars __user * ltchars)
331 if (copy_from_user(&tmp, ltchars, sizeof(tmp)))
334 tty->termios->c_cc[VSUSP] = tmp.t_suspc;
335 tty->termios->c_cc[VEOL2] = tmp.t_dsuspc; /* what is dsuspc anyway? */
336 tty->termios->c_cc[VREPRINT] = tmp.t_rprntc;
337 tty->termios->c_cc[VEOL2] = tmp.t_flushc; /* what is flushc anyway? */
338 tty->termios->c_cc[VWERASE] = tmp.t_werasc;
339 tty->termios->c_cc[VLNEXT] = tmp.t_lnextc;
345 * Send a high priority character to the tty.
347 void send_prio_char(struct tty_struct *tty, char ch)
349 int was_stopped = tty->stopped;
351 if (tty->driver->send_xchar) {
352 tty->driver->send_xchar(tty, ch);
357 tty->driver->write(tty, 0, &ch, 1);
362 int n_tty_ioctl(struct tty_struct * tty, struct file * file,
363 unsigned int cmd, unsigned long arg)
365 struct tty_struct * real_tty;
366 void __user *p = (void __user *)arg;
369 if (tty->driver->type == TTY_DRIVER_TYPE_PTY &&
370 tty->driver->subtype == PTY_TYPE_MASTER)
371 real_tty = tty->link;
378 return get_sgttyb(real_tty, (struct sgttyb __user *) arg);
381 return set_sgttyb(real_tty, (struct sgttyb __user *) arg);
385 return get_tchars(real_tty, p);
387 return set_tchars(real_tty, p);
391 return get_ltchars(real_tty, p);
393 return set_ltchars(real_tty, p);
396 if (kernel_termios_to_user_termios((struct termios __user *)arg, real_tty->termios))
400 return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT);
402 return set_termios(real_tty, p, TERMIOS_WAIT);
404 return set_termios(real_tty, p, 0);
406 return get_termio(real_tty, p);
408 return set_termios(real_tty, p, TERMIOS_FLUSH | TERMIOS_WAIT | TERMIOS_TERMIO);
410 return set_termios(real_tty, p, TERMIOS_WAIT | TERMIOS_TERMIO);
412 return set_termios(real_tty, p, TERMIOS_TERMIO);
414 retval = tty_check_change(tty);
419 if (!tty->flow_stopped) {
420 tty->flow_stopped = 1;
425 if (tty->flow_stopped) {
426 tty->flow_stopped = 0;
431 if (STOP_CHAR(tty) != __DISABLED_CHAR)
432 send_prio_char(tty, STOP_CHAR(tty));
435 if (START_CHAR(tty) != __DISABLED_CHAR)
436 send_prio_char(tty, START_CHAR(tty));
443 retval = tty_check_change(tty);
448 if (tty->ldisc.flush_buffer)
449 tty->ldisc.flush_buffer(tty);
452 if (tty->ldisc.flush_buffer)
453 tty->ldisc.flush_buffer(tty);
456 if (tty->driver->flush_buffer)
457 tty->driver->flush_buffer(tty);
464 return put_user(tty->driver->chars_in_buffer ?
465 tty->driver->chars_in_buffer(tty) : 0,
468 retval = tty->read_cnt;
470 retval = inq_canon(tty);
471 return put_user(retval, (unsigned int __user *) arg);
473 if (kernel_termios_to_user_termios((struct termios __user *)arg, real_tty->termios_locked))
478 if (!capable(CAP_SYS_ADMIN))
480 if (user_termios_to_kernel_termios(real_tty->termios_locked, (struct termios __user *) arg))
488 if (tty->driver->type != TTY_DRIVER_TYPE_PTY ||
489 tty->driver->subtype != PTY_TYPE_MASTER)
491 if (get_user(pktmode, (int __user *) arg))
496 tty->link->ctrl_status = 0;
503 return put_user(C_CLOCAL(tty) ? 1 : 0, (int __user *)arg);
505 if (get_user(arg, (unsigned int __user *) arg))
507 tty->termios->c_cflag =
508 ((tty->termios->c_cflag & ~CLOCAL) |
516 EXPORT_SYMBOL(n_tty_ioctl);