bsd/kern/tty.c

65  *	@(#)tty.c	8.8 (Berkeley) 1/21/94
118  * Debugging assertions for tty locks
133 static int	ttnread(struct tty *tp);
134 static void	ttyecho(int c, struct tty *tp);
135 static int	ttyoutput(int c, struct tty *tp);
136 static void	ttypend(struct tty *tp);
137 static void	ttyretype(struct tty *tp);
138 static void	ttyrub(int c, struct tty *tp);
139 static void	ttyrubo(struct tty *tp, int count);
140 static void	ttystop(struct tty *tp, int rw);
141 static void	ttyunblock(struct tty *tp);
142 static int	ttywflush(struct tty *tp);
145 static void	ttyhold(struct tty *tp);
146 static void	ttydeallocate(struct tty *tp);
148 static int isctty(proc_t p, struct tty  *tp);
149 static int isctty_sp(proc_t p, struct tty  *tp, struct session *sessp);
273  * Initialize the tty line discipline subsystem.
279  * Locks:	No ttys can be allocated and no tty locks can be used
283  *		lock group, and loc atribute for subsequent per-tty locks.
291 	tty_lck_grp = lck_grp_alloc_init("tty",  tty_lck_grp_attr);
299  * Lock the requested tty structure.
301  * Parameters:	tp				The tty we want to lock
308 tty_lock(struct tty *tp)
318  * Unlock the requested tty structure.
320  * Parameters:	tp				The tty we want to unlock
327 tty_unlock(struct tty *tp)
337  * Initial open of tty, or (re)entry to standard tty line discipline.
342 ttyopen(dev_t device, struct tty *tp)
347 	struct tty *oldtp;
364 	 * First tty open affter setsid() call makes this tty its controlling
365 	 * tty, if the tty does not already have a session associated with it.
368 	    sessp->s_ttyvp == NULL &&	/* but has no controlling tty */
369 	    tp->t_session == NULL ) {	/* and tty not controlling */
417  * Handle close() on a tty line: flush and set to initial state,
419  * can detect recycling of the tty.
427 ttyclose(struct tty *tp)
439 		 * Closing current console tty; disable printing of console
486  * Process input of a single character received on a tty.
489  *		tp			The tty on which it was received
496 ttyinput(int c, struct tty *tp)
867  * Output a single character on a tty, doing output processing
871  *		tp			The tty on which to output on the tty
881 ttyoutput(int c, struct tty *tp)
982 ttioctl(struct tty *tp, u_long cmd, caddr_t data, int flag, proc_t p)
997  * Ioctls for all tty devices.
1015  *		ENOTTY			TIOCGPGRP on a non-controlling tty
1020  *					tty
1052 ttioctl_locked(struct tty *tp, u_long cmd, caddr_t data, int flag, proc_t p)
1058 	struct tty *oldtp;
1136 	case TIOCEXCL:			/* set exclusive use of tty */
1203 	case TIOCGPGRP:			/* get pgrp of tty */
1215 	case TIOCNXCL:			/* reset exclusive use of tty */
1386 	case TIOCSCTTY:			/* become controlling tty */
1431 	case TIOCSPGRP: {		/* set pgrp of tty */
1510 ttyselect(struct tty *tp, int rw, void *wql, proc_t p)
1560 	struct tty *tp = cdevsw[major(dev)].d_ttys[minor(dev)];
1574 ttnread(struct tty *tp)
1611 ttywait(struct tty *tp)
1646 ttystop(struct tty *tp, int rw)
1659 ttywflush(struct tty *tp)
1671  * Flush tty read and/or write queues, notifying anyone waiting.
1676 ttyflush(struct tty *tp, int rw)
1761 ttyblock(struct tty *tp)
1781 ttyunblock(struct tty *tp)
1796  * Start tty output
1798  * Parameters:	tp			tty on which to start output
1810 ttstart(struct tty *tp)
1829 ttylclose(struct tty *tp, int flag)
1843  * Handle modem control transition on a tty.
1850 ttymodem(struct tty *tp, int flag)
1910 ttypend(struct tty *tp)
1931  * Process a read call on a tty device.
1936 ttread(struct tty *tp, struct uio *uio, int flag)
2237  * lose messages due to normal flow control, but don't let the tty run amok.
2246 ttycheckoutq(struct tty *tp, int wait)
2276  * Process a write call on a tty device.
2281 ttwrite(struct tty *tp, struct uio *uio, int flag)
2484 ttyrub(int c, struct tty *tp)
2570 ttyrubo(struct tty *tp, int count)
2590 ttyretype(struct tty *tp)
2625 ttyecho(int c, struct tty *tp)
2650  * Wake up any readers on a tty.
2655 ttwakeup(struct tty *tp)
2663 		 * XXX: Callers may not revalidate it the tty is closed
2681  * Wake up any writers on a tty.
2686 ttwwakeup(struct tty *tp)
2712  *		directly access struct tty.
2725  * Set tty hi and low water marks.
2733 ttsetwater(struct tty *tp)
2766 ttyinfo_locked(struct tty *tp)
2901  *		tty_lock(tp) for p2's tty, for which p2 is the foreground
2958  * Output char to tty; console putchar style.
2965 tputchar(int c, struct tty *tp)
3004  * Sleep on chan, returning ERESTART if tty changed while we napped and
3006  * the tty is revoked, restarting a pending call will redo validation done
3010 ttysleep(struct tty *tp, void *chan, int pri, const char *wmesg, int timo)
3027  * Allocate a tty structure and its associated buffers.
3031  * Returns:	!NULL				Address of new struct tty
3034  * Locks:	The tty_lock() of the returned tty is not held when it
3037 struct tty *
3040 	struct tty *tp;
3042 	MALLOC(tp, struct tty *, sizeof(struct tty), M_TTYS, M_WAITOK|M_ZERO);
3058  * Increment the reference count on a tty.
3061 ttyhold(struct tty *tp)
3068  * Drops a reference count on a tty structure; if the reference count reaches
3072 ttyfree(struct tty *tp)
3081 		panic("%s: freeing free tty %p", __func__, tp);
3087  * Deallocate a tty structure and its buffers.
3093 ttydeallocate(struct tty *tp)
3099 		panic("knotes hooked into a tty when the tty is freed.\n");
3115 isbackground(proc_t p, struct tty  *tp)
3123 isctty(proc_t p, struct tty  *tp)
3135 isctty_sp(proc_t p, struct tty  *tp, struct session *sessp)