#include <core/system.h>
#include <aquila/termios.h>
#include <aquila/ioctl.h>
#include <sys/proc.h>
#include <fs/iobuf.h>

Data Structures
struct	tty
	A terminal, and its line discipline's state. More...

Macros
#define	TTY_BUF_SIZE 512

Typedefs
typedef ssize_t(*)	ttyio(struct tty tty, size_t size, void buf)

Functions
int	tty_new (struct proc proc, size_t buf_size, ttyio master, ttyio slave, void p, struct tty **ref)
	Makes a new terminal, with the default modes (canonical, echo, signals, ICRNL, IXON, OPOST with ONLCR) and the usual special characters.
int	tty_free (struct tty *tty)
	Ends a terminal: it is hung up, and freed.
ssize_t	tty_master_write (struct tty tty, size_t size, void buf)
	Takes input from the terminal's device (the keyboard, a UART, or a pseudo-terminal's master), and puts it through the line discipline to what programs read.
ssize_t	tty_slave_write (struct tty tty, size_t size, void buf)
	Takes what programs write to the terminal, and sends it to the device through output processing (OPOST, POSIX's output modes): NL as CR NL (ONLCR), CR as NL (OCRNL), no CR in the first column (ONOCR), and NL returning the carriage too (ONLRET).
ssize_t	tty_write_iobuf (struct tty tty, struct iobuf io, ttyio write)
	Writes to a terminal from an iobuf (user memory), to either side: a piece at a time through a kernel buffer, the iobuf moved on only as far as was taken.
int	tty_ioctl (struct tty tty, int request, void argp)
	Handles a terminal's ioctl()s: its modes (TCGETS, TCSETS, ...), flushing, its session and foreground group, its window size, and becoming the controlling terminal (TIOCSCTTY).
void	tty_open (struct tty tty, struct file file)
	Handles a terminal device being opened: it becomes the controlling terminal of a session leader that has none (unless O_NOCTTY), if no session has it already.
void	tty_hangup (struct tty *tty)
	Hangs up a controlling terminal, when its session ends (its leader exited) or the terminal goes away: its foreground group gets SIGHUP (and SIGCONT, in case it was stopped), and the terminal belongs to no session anymore.
void	tty_flush (struct tty *tty, int which)
	Drops a terminal's input (TCIFLUSH, TCIOFLUSH): the line being edited, what the device holds for readers, and the pending end-of-files.
int	tty_eof (struct tty *tty)
	Says whether a read that found nothing to return should return 0 at once: at an end-of-file (VEOF at the start of a line), or with VMIN and VTIME both 0 in non-canonical mode.
uint64_t	tty_read_timeout (struct tty *tty)
	Says how long a read waits for input: VTIME tenths of a second with VMIN 0 in non-canonical mode, otherwise until there is some.
int	tty_can_read (struct tty *tty, size_t buffered)
	Says whether the terminal is readable, for select() and poll(): there is input, or an end-of-file.
int	tty_background (struct tty *tty, int sig)
	Stops a background process that reads the terminal, writes it or changes it: if the current process is of the terminal's session but not of its foreground group, its group gets the signal and stops until it is continued in the foreground.

Macro Definition Documentation

◆ TTY_BUF_SIZE

#define TTY_BUF_SIZE 512

Definition at line 84 of file tty.h.

Referenced by tty_new().

Typedef Documentation

◆ ttyio

typedef ssize_t(*) ttyio(struct tty *tty, size_t size, void *buf)

Definition at line 22 of file tty.h.

Function Documentation

◆ tty_background()

int tty_background	(	struct tty *	tty,
		int	sig )

Stops a background process that reads the terminal, writes it or changes it: if the current process is of the terminal's session but not of its foreground group, its group gets the signal and stops until it is continued in the foreground.

Writes are only stopped with TOSTOP, which the callers check.

Parameters

tty	the terminal
sig	SIGTTIN for a read, SIGTTOU for a write or a change

Returns: 0 if the process may go on; -ERESTARTSYS once the signal is sent (the call returns, the group stops on its way out, and the call is made again once it is continued); or -EIO for a read with SIGTTIN ignored or blocked, or from an orphaned group

Definition at line 259 of file generic.c.

References curproc, ERESTARTSYS, tty::fg, NULL, proc::pgrp, pgrp_orphaned(), pgroup::session, tty::session, SIG_IGN, proc::sigaction, proc::sigmask, signal_pgrp_send(), and tty_background().

Referenced by pts_read(), pts_write(), tty_background(), tty_ioctl(), uart_read(), uart_write(), vt_read(), and vt_write().

◆ tty_can_read()

int tty_can_read	(	struct tty *	tty,
		size_t	buffered )

Says whether the terminal is readable, for select() and poll(): there is input, or an end-of-file.

With VMIN and VTIME 0 a read doesn't wait either, but it isn't readable without input, as on Linux and the BSDs: a program that waits for input in select() would otherwise never sleep.

Parameters

tty	the terminal
buffered	how many bytes the device holds for readers

Returns: whether there is something to read

Definition at line 240 of file generic.c.

References tty::eof, and tty_can_read().

Referenced by pts_can_read(), tty_can_read(), uart_can_read(), and vt_can_read().

◆ tty_eof()

int tty_eof ( struct tty * tty )

Says whether a read that found nothing to return should return 0 at once: at an end-of-file (VEOF at the start of a line), or with VMIN and VTIME both 0 in non-canonical mode.

An end-of-file is used up.

Parameters

tty	the terminal

Returns: 1 if the read returns 0, 0 if it waits

Definition at line 200 of file generic.c.

References tty::eof, tty::tios, and tty_eof().

Referenced by pts_eof(), tty_eof(), uart_file_eof(), and vt_file_eof().

◆ tty_flush()

void tty_flush	(	struct tty *	tty,
		int	which )

Drops a terminal's input (TCIFLUSH, TCIOFLUSH): the line being edited, what the device holds for readers, and the pending end-of-files.

Output isn't kept anywhere, so there is none to drop.

Parameters

tty	the terminal
which	TCIFLUSH, TCOFLUSH or TCIOFLUSH

Definition at line 691 of file generic.c.

References tty::eof, tty::input_flush, tty::pos, and tty_flush().

Referenced by tty_flush(), and tty_ioctl().

◆ tty_free()

int tty_free ( struct tty * tty )

Ends a terminal: it is hung up, and freed.

If writers are waiting for its output to start again, they are woken up instead, and the last one frees it.

Parameters

tty	the terminal

Returns: 0

Definition at line 718 of file generic.c.

References tty::gone, tty::start_wait, tty::start_waiters, tty::stopped, tty_free(), tty_hangup(), tty_release(), and waitq_wakeup().

Referenced by pty_free(), pty_new(), and tty_free().

◆ tty_hangup()

void tty_hangup ( struct tty * tty )

Hangs up a controlling terminal, when its session ends (its leader exited) or the terminal goes away: its foreground group gets SIGHUP (and SIGCONT, in case it was stopped), and the terminal belongs to no session anymore.

Parameters

tty	the terminal

Definition at line 668 of file generic.c.

References session::ctty, tty::fg, NULL, tty::session, signal_pgrp_send(), and tty_hangup().

Referenced by proc_kill(), tty_free(), and tty_hangup().

◆ tty_ioctl()

int tty_ioctl	(	struct tty *	tty,
		int	request,
		void *	argp )

Handles a terminal's ioctl()s: its modes (TCGETS, TCSETS, ...), flushing, its session and foreground group, its window size, and becoming the controlling terminal (TIOCSCTTY).

Parameters

tty	the terminal
request	the request
argp	its argument, in user memory (or the value itself, for TCFLSH)

Returns: 0 or what the request returns, or a negative errno (-ENOTTY for a request terminals don't have)

Definition at line 455 of file generic.c.

References session::ctty, curproc, tty::fg, session::leader, NULL, pgroup::pgid, session::pgps, queue_for, tty::session, session::sid, tty::start_wait, tty::stopped, tty::tios, tty_background(), tty_flush(), tty_ioctl(), waitq_wakeup(), and tty::ws.

Referenced by pty_ioctl(), tty_ioctl(), uart_ioctl(), and vt_ioctl().

◆ tty_master_write()

ssize_t tty_master_write	(	struct tty *	tty,
		size_t	size,
		void *	buf )

Takes input from the terminal's device (the keyboard, a UART, or a pseudo-terminal's master), and puts it through the line discipline to what programs read.

Canonical mode collects lines, with erase (VERASE), kill (VKILL) and end-of-file (VEOF); otherwise, the programs get the characters as they come.

Parameters

tty	the terminal
size	the input's size, in bytes
buf	the input

Returns: size: all of it is taken (what doesn't fit in a line is dropped)

Definition at line 111 of file generic.c.

References tty::cook, tty::eof, IS_CC, tty::pos, tty::size, tty::slave_write, tty::start_wait, tty::stopped, tty::tios, tty_deliver(), tty_echo(), tty_erase(), tty_master_write(), tty_signal(), and waitq_wakeup().

Referenced by ptm_write(), tty_master_write(), uart_receive_handler(), and vt_input_to().

◆ tty_new()

int tty_new	(	struct proc *	proc,
		size_t	buf_size,
		ttyio	master,
		ttyio	slave,
		void *	p,
		struct tty **	ref )

Makes a new terminal, with the default modes (canonical, echo, signals, ICRNL, IXON, OPOST with ONLCR) and the usual special characters.

Parameters

proc	the process making it (not used)
buf_size	the size of its line buffer, or 0 for TTY_BUF_SIZE
master	how the terminal sends output to its device
slave	how the terminal hands input to its readers
p	the device's own data, for those two
ref	set to the new terminal

Returns: 0, or -ENOMEM

Definition at line 584 of file generic.c.

References tty::col, tty::cook, kfree(), kmalloc(), M_ZERO, tty::master_write, tty::nl_owed, NULL, tty::p, tty::pos, tty::size, tty::slave_write, tty::tios, TTY_BUF_SIZE, tty_new(), and tty::ws.

Referenced by pty_new(), tty_new(), uart_setup(), and vt_setup().

◆ tty_open()

void tty_open	(	struct tty *	tty,
		struct file *	file )

Handles a terminal device being opened: it becomes the controlling terminal of a session leader that has none (unless O_NOCTTY), if no session has it already.

Opening /dev/console doesn't do it, as on Linux: init writes there, and would otherwise take the terminal that is also the console (the first virtual terminal, or the UART) from the session that a getty starts on it.

Parameters

tty	the terminal
file	the file being opened

Definition at line 646 of file generic.c.

References session::ctty, curproc, DEV, tty::fg, file::flags, session::leader, tty::session, and tty_open().

Referenced by pts_open(), tty_open(), uart_file_open(), and vt_file_open().

◆ tty_read_timeout()

uint64_t tty_read_timeout ( struct tty * tty )

Says how long a read waits for input: VTIME tenths of a second with VMIN 0 in non-canonical mode, otherwise until there is some.

Parameters

tty	the terminal

Returns: the time, in ns, or 0 for no limit

Definition at line 221 of file generic.c.

References tty::tios, and tty_read_timeout().

Referenced by pts_read_timeout(), tty_read_timeout(), uart_read_timeout(), and vt_read_timeout().

◆ tty_slave_write()

ssize_t tty_slave_write	(	struct tty *	tty,
		size_t	size,
		void *	_buf )

Takes what programs write to the terminal, and sends it to the device through output processing (OPOST, POSIX's output modes): NL as CR NL (ONLCR), CR as NL (OCRNL), no CR in the first column (ONOCR), and NL returning the carriage too (ONLRET).

The column is tracked for them.

Parameters

tty	the terminal
size	the output's size, in bytes
_buf	the output

Returns: how many bytes of it went (the device may take fewer)

Definition at line 297 of file generic.c.

References tty::col, tty::master_write, tty::nl_owed, tty::tios, tty_out(), and tty_slave_write().

Referenced by pts_write(), tty_echo(), tty_erase(), tty_signal(), tty_slave_write(), tty_write_iobuf(), uart_write(), and vt_write().

◆ tty_write_iobuf()

ssize_t tty_write_iobuf	(	struct tty *	tty,
		struct iobuf *	io,
		ttyio	write )

Writes to a terminal from an iobuf (user memory), to either side: a piece at a time through a kernel buffer, the iobuf moved on only as far as was taken.

Parameters

tty	the terminal
io	what to write
write	the side: tty_master_write (input, from a pseudo-terminal's master) or tty_slave_write (a program's output)

Returns: how many bytes were written, or a negative errno

Definition at line 408 of file generic.c.

References iobuf_peek(), iobuf_skip(), MIN, iobuf::resid, tty::stopped, tty_slave_write(), tty_wait_start(), and tty_write_iobuf().

Referenced by ptm_write(), pts_write(), tty_write_iobuf(), uart_write(), and vt_write().

Data Structures

Macros

Typedefs

Functions

Macro Definition Documentation

◆ TTY_BUF_SIZE

Typedef Documentation

◆ ttyio

Function Documentation

◆ tty_background()

◆ tty_can_read()

◆ tty_eof()

◆ tty_flush()

◆ tty_free()

◆ tty_hangup()

◆ tty_ioctl()

◆ tty_master_write()

◆ tty_new()

◆ tty_open()

◆ tty_read_timeout()

◆ tty_slave_write()

◆ tty_write_iobuf()