* Copyright (c) 1988 Mark Nudleman
* Copyright (c) 1988, 1993
* The Regents of the University of California. All rights reserved.
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
static char sccsid
[] = "@(#)screen.c 8.2 (Berkeley) 4/20/94";
* Routines which deal with the characteristics of the terminal.
* Uses termcap to be as terminal-independent as possible.
* {{ Someday this should be rewritten to use curses. }}
* For the Unix PC (ATT 7300 & 3B1):
* Since WIOCGETD is defined in sys/window.h, we can't use that to decide
* whether to include sys/window.h. Use SIGPHONE from sys/signal.h instead.
* Strings passed to tputs() to do various terminal functions.
*sc_pad
, /* Pad string */
*sc_home
, /* Cursor home */
*sc_addline
, /* Add line, scroll down following lines */
*sc_lower_left
, /* Cursor to last line, first column */
*sc_move
, /* General cursor positioning */
*sc_clear
, /* Clear screen */
*sc_eol_clear
, /* Clear to end of line */
*sc_s_in
, /* Enter standout (highlighted) mode */
*sc_s_out
, /* Exit standout mode */
*sc_u_in
, /* Enter underline mode */
*sc_u_out
, /* Exit underline mode */
*sc_b_in
, /* Enter bold mode */
*sc_b_out
, /* Exit bold mode */
*sc_backspace
, /* Backspace cursor */
*sc_init
, /* Startup terminal initialization */
*sc_deinit
; /* Exit terminal de-intialization */
int auto_wrap
; /* Terminal does \r\n when write past margin */
int ignaw
; /* Terminal ignores \n immediately after wrap */
/* The user's erase and line-kill chars */
int retain_below
; /* Terminal retains text below the screen */
int erase_char
, kill_char
, werase_char
;
int sc_width
, sc_height
= -1; /* Height & width of screen */
int sc_window
= -1; /* window size for forward and backward */
int bo_width
, be_width
; /* Printing width of boldface sequences */
int ul_width
, ue_width
; /* Printing width of underline sequences */
int so_width
, se_width
; /* Printing width of standout sequences */
* These two variables are sometimes defined in,
* and needed by, the termcap library.
* It may be necessary on some systems to declare them extern here.
/*extern*/ short ospeed
; /* Terminal output baud rate */
/*extern*/ char PC
; /* Pad character */
* Change terminal to "raw mode", or restore to "normal" mode.
* 1. An outstanding read will complete on receipt of a single keystroke.
* 2. Input is not echoed.
* 3. On output, \n is mapped to \r\n.
* 4. \t is NOT expanded into spaces.
* 5. Signal-causing characters such as ctrl-C (interrupt),
* It doesn't matter whether an input \n is mapped to \r, or vice versa.
static struct termio save_term
;
static struct termios save_term
;
(void)ioctl(2, TCGETA
, &s
);
* Save modes and set certain variables dependent on modes.
ospeed
= s
.c_cflag
& CBAUD
;
ospeed
= cfgetospeed(&s
);
erase_char
= s
.c_cc
[VERASE
];
kill_char
= s
.c_cc
[VKILL
];
werase_char
= s
.c_cc
[VWERASE
];
* Set the modes to the way we want them.
s
.c_lflag
&= ~(ICANON
|ECHO
|ECHOE
|ECHOK
|ECHONL
);
s
.c_oflag
|= (OPOST
|ONLCR
|TAB3
);
s
.c_oflag
&= ~(OCRNL
|ONOCR
|ONLRET
);
(void)ioctl(2, TCSETAW
, &s
);
tcsetattr(2, TCSADRAIN
, &s
);
static struct sgttyb save_term
;
(void)ioctl(2, TIOCGETP
, &s
);
(void)ioctl(2, TIOCGLTC
, &l
);
* Save modes and set certain variables dependent on modes.
werase_char
= l
.t_werasc
;
* Set the modes to the way we want them.
s
.sg_flags
&= ~(ECHO
|XTABS
);
(void)ioctl(2, TIOCSETN
, &s
);
* Get terminal capabilities via termcap.
char *getenv(), *strcpy();
* Find out what kind of terminal this is.
if ((term
= getenv("TERM")) == NULL
)
if (tgetent(termbuf
, term
) <= 0)
(void)strcpy(termbuf
, "dumb:co#80:hc:");
* Get size of the screen.
if (ioctl(2, TIOCGWINSZ
, &w
) == 0 && w
.ws_row
> 0)
if (ioctl(2, WIOCGETD
, &w
) == 0 && w
.uw_height
> 0)
sc_height
= w
.uw_height
/w
.uw_vs
;
sc_height
= tgetnum("li");
hard
= (sc_height
< 0 || tgetflag("hc"));
/* Oh no, this is a hardcopy terminal. */
if (ioctl(2, TIOCGWINSZ
, &w
) == 0 && w
.ws_col
> 0)
if (ioctl(2, WIOCGETD
, &w
) == 0 && w
.uw_width
> 0)
sc_width
= w
.uw_width
/w
.uw_hs
;
sc_width
= tgetnum("co");
auto_wrap
= tgetflag("am");
retain_below
= tgetflag("db");
* Assumes termcap variable "sg" is the printing width of
* the standout sequence, the end standout sequence,
* the underline sequence, the end underline sequence,
* the boldface sequence, and the end boldface sequence.
if ((so_width
= tgetnum("sg")) < 0)
be_width
= bo_width
= ue_width
= ul_width
= se_width
= so_width
;
* Get various string-valued capabilities.
sc_pad
= tgetstr("pc", &sp
);
sc_init
= tgetstr("ti", &sp
);
sc_deinit
= tgetstr("te", &sp
);
sc_eol_clear
= tgetstr("ce", &sp
);
if (hard
|| sc_eol_clear
== NULL
|| *sc_eol_clear
== '\0')
sc_clear
= tgetstr("cl", &sp
);
if (hard
|| sc_clear
== NULL
|| *sc_clear
== '\0')
sc_move
= tgetstr("cm", &sp
);
if (hard
|| sc_move
== NULL
|| *sc_move
== '\0')
* This is not an error here, because we don't
* We need it only if we don't have home or lower-left.
sc_s_in
= tgetstr("so", &sp
);
if (hard
|| sc_s_in
== NULL
)
sc_s_out
= tgetstr("se", &sp
);
if (hard
|| sc_s_out
== NULL
)
sc_u_in
= tgetstr("us", &sp
);
if (hard
|| sc_u_in
== NULL
)
sc_u_out
= tgetstr("ue", &sp
);
if (hard
|| sc_u_out
== NULL
)
sc_b_in
= tgetstr("md", &sp
);
if (hard
|| sc_b_in
== NULL
)
sc_b_out
= tgetstr("me", &sp
);
if (hard
|| sc_b_out
== NULL
)
sc_home
= tgetstr("ho", &sp
);
if (hard
|| sc_home
== NULL
|| *sc_home
== '\0')
* This last resort for sc_home is supposed to
* be an up-arrow suggesting moving to the
* top of the "virtual screen". (The one in
* your imagination as you try to use this on
* but we can use "move(0,0)".
(void)strcpy(sp
, tgoto(sc_move
, 0, 0));
sc_lower_left
= tgetstr("ll", &sp
);
if (hard
|| sc_lower_left
== NULL
|| *sc_lower_left
== '\0')
* No "lower-left" string,
* but we can use "move(0,last-line)".
(void)strcpy(sp
, tgoto(sc_move
, 0, sc_height
-1));
* To add a line at top of screen and scroll the display down,
* we use "al" (add line) or "sr" (scroll reverse).
if ((sc_addline
= tgetstr("al", &sp
)) == NULL
||
sc_addline
= tgetstr("sr", &sp
);
if (hard
|| sc_addline
== NULL
|| *sc_addline
== '\0')
/* Force repaint on any backward movement */
sc_backspace
= tgetstr("bc", &sp
);
if (sc_backspace
== NULL
|| *sc_backspace
== '\0')
* Below are the functions which perform all the
* terminal-specific screen manipulation.
tputs(sc_init
, sc_height
, putchr
);
tputs(sc_deinit
, sc_height
, putchr
);
* Home cursor (move to upper left corner of screen).
tputs(sc_home
, 1, putchr
);
* Add a blank line (called with cursor at home).
* Should scroll the display down.
tputs(sc_addline
, sc_height
, putchr
);
int short_file
; /* if file less than a screen */
tputs(sc_lower_left
, 1, putchr
);
* Ring the terminal bell.
tputs(sc_clear
, sc_height
, putchr
);
* Clear from the cursor to the end of the cursor's line.
* {{ This must not move the cursor. }}
tputs(sc_eol_clear
, 1, putchr
);
* Begin "standout" (bold, underline, or whatever).
tputs(sc_s_in
, 1, putchr
);
tputs(sc_s_out
, 1, putchr
);
* Begin "underline" (hopefully real underlining,
* otherwise whatever the terminal provides).
tputs(sc_u_in
, 1, putchr
);
tputs(sc_u_out
, 1, putchr
);
tputs(sc_b_in
, 1, putchr
);
tputs(sc_b_out
, 1, putchr
);
* Erase the character to the left of the cursor
* and move the cursor left.
* Try to erase the previous character by overstriking with a space.
tputs(sc_backspace
, 1, putchr
);
tputs(sc_backspace
, 1, putchr
);
* Output a plain backspace, without erasing the previous char.
tputs(sc_backspace
, 1, putchr
);