[net.sources] DPY - New terminal display routines

dbell@daisy.UUCP (David I. Bell) (01/29/85)

This message (and the next) contains a set of library routines which in many
cases can replace curses(3).  My main reasons for writing this are:
	1.	Curses is too slow.
	2.	The way that curses handles windows is obscure.
	3.	These new routines were fun to write.

Suggestions and bug fixes are welcome.  Enjoy!

#---Cut here and place in it's own directory, then feed to Bourne shell---
# This is a shell archive.  Remove anything before this line, then
# unpack it by saving it in a file and typing "sh file".  (Files
# unpacked will be owned by you and have default permissions.)
# This archive contains:
#   README (1213 chars)
#   dpy.doc (14459 chars)
#   makefile (1058 chars)
#   test1.c (503 chars)
#   test2.c (1314 chars)
#
echo x - README
sed -e 's/^X//' > "README" << '//E*O*F README//'
XThese routines were built for a 4.2 BSD UNIX system running on a VAX 750.
X
XIf you are running under another version of UNIX, you have to fix the
Xplaces where signals or ioctls are used (and probably more too).  Since
Xthis is the only version of UNIX I have access to, I don't know how well
Xit will port.
X
XIf you are running under a different machine, you have to change the makefile
Xto use gensubs.c instead of vaxsubs.s (this contains generic subroutines which
Xrun on all machines).  If you are ambitious, you can speed up dpy by writing
Xyour own assembly level routines to duplicate what gensubs.c does.  Not much
Xassembly code is needed.  (If you are real lucky, you are on a 32016, and the
Xnecessary routines are already written in m16subs.s.)  I am willing to collect
Xand distribute such subroutines for some other machines.
X
XI have included two toy programs (test1.c and test2.c) which demonstrate some
Xof the capabilities of dpy.  Along with dpy.doc, they should show you how to
Xuse the module.  I am sorry that dpy.doc is not formatted.  If I waited until
XI got around to making it pretty, this module would probably never get out!
X
XComments and bug fixes are welcome.
X			David I. Bell
X			nsc!daisy!dbell
//E*O*F README//
echo x - dpy.doc
sed -e 's/^X//' > "dpy.doc" << '//E*O*F dpy.doc//'
X		DPY - New Screen Updating Routines
X			by David I. Bell
X
X
XDpy is a terminal display package much like curses(3).  Dpy does not
Xprovide all of the capabilities of curses, but instead tries to focus on
Xthe following two goals:
X1.	Allow the programmer to easily define and update many different
X	rectangles of data on the screen at the same time.
X2.	Be as fast as possible.
X
XThe routines in the dpy library are called directly by the user program.
XNone of these routines are a macro, so that there is no need to include a
Xheader file to use dpy.  These routines use the termlib (or termcap) library
Xroutines to obtain the proper terminal escape sequences.  Therefore, you
Xload your program as in the following example:
X	cc -o yourprog yourprog.c -ldpy -ltermlib.
X
XDpy keeps two arrays which hold images of the terminal screen.  The first
Xarray (the "current screen") is a copy of what the terminal screen really
Xlooks like.  The second array (the "future screen") is a copy of what the
Xcalling program wants the screen to look like.  The use of dpy proceeds in
Xtwo phases under the control of the calling program, as follows:
X
XIn the first phase, only the future screen is manipulated.  The calling
Xprogram positions the "current write location" as desired within the future
Xscreen, and writes new information within it.  During this phase, no actual
XI/O occurs and the terminal screen remains unchanged.
X
XIn the second phase, the calling program asks dpy to update the screen.
XDpy compares the future screen contents with the current screen contents,
Xand does whatever terminal I/O is required in order to make the current
Xscreen look like the future screen.  After this is done, the two screen
Ximages are identical.
X
XThe calling program usually uses dpy by looping between the above two
Xphases.  First, it defines what the screen should look like, and then
Xthe screen is updated, then it defines the screen again, and so on.  In
Xdoing so, the program can be "dumb" or "smart".  A dumb program rewrites
Xall of the data in its windows each iteration of the loop, and depends on
Xdpy to prevent terminal I/O for unchanging data.  Thus a dumb program
Xcan be very trivial, and doesn't have to know anything about what is
Xhappening on the screen.  A smart program knows the exact locations of the
Xdesired screen changes each iteration of the loop, and only rewrites those
Xlocations.  This runs somewhat faster than a dumb program, but has the
Xdisadvantage of introducing complexity and possible bugs into the program.
XIf generating a new screen of data is too much work for each iteration,
Xa good compromise is to keep an internal copy of the screen in the program,
Xupdate that appropriately, and give that whole screen to dpy each iteration.
X
XPutting data into the future screen is much like writing to a real terminal.
XThere is a "current write location", which is similar to the cursor of the
Xterminal.  Like a terminal, characters written to dpy appear at the current
Xwrite location, and automatically advance its location.  When the rightmost
Xlocation on a line is reached, the current write location is automatically
Xmoved to the leftmost location on the next line.  Finally, some control
Xcharacters have special effects like on a terminal.  In particular, linefeed
Xmoves to the beginning of the next line, return moves back to the beginning
Xof the current line, tab moves to the next tab stop as if the corresponding
Xnumber of spaces were given, and backspace backs up by one location.  Other
Xcontrol characters appear in ^X format.
X
XThere are some differences between writing to the future screen and most real
Xterminals, however.  Firstly, scrolling does not usually occur.  If the end of
Xthe screen is reached, any further characters are ignored.  Secondly, it is
Xpossible to limit output to a "window", which is a rectangle of any size on
Xthe screen.  The location and size of a window is specified by the program
Xwhen it wants to limit output to a rectangle.  This window acts just like
Xa regular terminal screen of the appropriate size.  Furthermore, coordinates
Xare relative to the window's upper left corner, so a routine which writes
Xin the window does not need to know where it is.  Data in the future screen
Xwhich lies outside of the window is untouched, no matter what is done within
Xthe window.  Typically, a program divides the screen up into several windows
Xwhich do not overlap.  Data can then be written to each window independently,
Xwithout regard to where each window is.  For example, a linefeed character
Xmoves to the beginning of the next line in the current window, instead of
Xto the beginning of the next line of the screen.
X
XThe following is a description of the procedures available in the dpy library:
X
Xdpyinit(ttytype, modeset, modeclear)
X	This routine must be called before any other call to dpy (except for
X	dpyclose).  It allocates memory for the two screen images for dpy,
X	defines the current window to be the whole screen, sets the current
X	write location to the upper left corner of the screen, and uses
X	signal(2) to cause the terminal stop character to trap to dpystop for
X	pretty program stopping.  The terminal screen itself is not cleared
X	until the first dpyupdate call is made, so that you can initialize
X	your program based upon the terminal size before deciding to continue.
X	Returns nonzero with an error message typed if cannot initialize.
X	ttytype/	the terminal type string, or NULL to use the TERM
X			environment variable value
X	modeset/	bits in terminal flags to set (usually CBREAK)
X	modeclear/	bits in terminal flags to clear (usually ECHO)
X
Xdpyclose()
X	Homes down to the lower left corner and clears the last line of the
X	terminal screen, frees the memory allocated by dpyinit, and resets
X	the original terminal modes.  Useful when exiting your program.
X	If dpyinit has not yet been called, nothing is done, so it is safe
X	to call dpyclose at any time.
X
Xdpywrite(buf, count)
X	Writes characters to the future screen image at the current write
X	location in the current window, and updates the current write
X	location appropriately.  This does not do any I/O to the terminal
X	(dpyupdate does that).  Control characters are handled appropriately,
X	as is running off the end of a line or the window.  This routine is
X	called by dpychar, dpystr, and dpyprintf, and is therefore the most
X	efficient way to give characters to dpy.  Returns nonzero if not all
X	characters fit in the window.
X	buf/		address of characters to write
X	count/		number of characters to write
X
Xdpychar(ch)
X	Writes a single character to the future screen image.  Returns nonzero
X	if the character couldn't fit in the window.
X	ch/		character to write
X
Xdpystr(str)
X	Writes a null terminated string to the future screen image.  Returns
X	nonzero if some of string couldn't fit in the window.
X	str/		address of string to write
X
Xdpyprintf(fmt [,args] ...)
X	Writes a formated string to the future screen image, in the
X	manner of printf.  Returns nonzero if some of the string couldn't
X	fit in the window.
X	fmt/		format string
X	args/		list of arguments for format string
X
Xdpyclearline()
X	Clears the rest of the line in the future screen image (by changing
X	the characters to spaces), but does not change the current write
X	location.  Writing a linefeed to the future screen performs this
X	function, in addition to moving the write location to the next line.
X
Xdpyclearwindow()
X	Clears the rest of the window in the future screen image, but
X	does not change the current write location.  When rewriting a
X	window completely, this should be called when done so that any
X	old contents of the window will be sure to be cleared out.
X
Xdpyhome()
X	Moves the current write location to the top left corner of the window.
X	When being a dumb program which rewrites the whole window, this needs
X	to be called between iterations.
X
Xdpygetrow()
X	Returns the row number of the current write location.  This is
X	the row number where the next character written would go.  If the
X	next character written would not fit in the window, -1 is returned.
X	This number is relative to the first line of the current window.
X	For example, if the current write location is at the beginning of
X	the top line of the window, this function returns zero.
X
Xdpygetcol()
X	Returns the column number of the current write location.  This is
X	the column number where is next character written would go.  If the
X	next character written would not fit in the window, -1 is returned.
X	This number is relative to the current window.  For example, if
X	the current write location is at the beginning of a line in the
X	window, this function returns zero.
X
Xdpyupdate()
X	Makes the terminal screen look like the future screen image,
X	using a minimal amount of terminal I/O.  The cursor is positioned
X	at the current write location when this function is done.
X
Xdpyredraw()
X	Redraws the screen to make it look like the current screen image.
X	Used to fix the screen when it becomes trashed due to glitches or
X	other programs also writing to the screen.  This does not change
X	the current or future screen images.
X
Xdpystop()
X	Suspends execution of the process in a nice way.  Homes down to
X	the lower left corner, clears the last line, resets terminal modes,
X	and then stops the process.  If the process is continued, terminal
X	modes are restored, the screen is redrawn, and execution proceeds.
X	This is called automatically when the terminal stop character is typed
X	by the user.
X
Xdpymove(row, col)
X	Changes the current write location to the given row and column
X	numbers, relative to the upper left corner of the current window.
X	Coordinates start at zero.  Negative numbers measure from the last
X	row or column of the window.  For example, dpymove(-1, 0) positions
X	to the beginning of the last line of the window.  This does not set
X	the actual terminal's cursor location, unless this is also followed
X	by a call to dpyupdate.  Returns nonzero if the coordinates are
X	illegal.
X
Xdpyplace(row, col, ch)
X	Place the given character at the given coordinates within the
X	current window, without changing the current write location.  The
X	character placed should not be a control character.  The coordinates
X	can be negative to measure from the last row or column of the window.
X	Like dpywrite and similar routines, this routine only affects the
X	future screen image, and does no terminal I/O.  Returns nonzero if
X	the coordinates are illegal.
X
Xdpyget(row, col)
X	Returns the character which is at the given coordinates within the
X	current window, without changing the current write location.  The
X	coordinates can be negative to measure from the last row or column of
X	the window.  The character returned is from the future screen image,
X	not the current screen image.  Returns negative if the coordinates
X	are illegal.
X
Xdpyread(prompt, routine, buf, count)
X	This is used to read data from the user, while showing the input
X	data on the screen.  The current window is used for this purpose.
X	Editing of the input and updating of the screen is automatically
X	performed by dpy.  To use this feature properly do the following:
X	1.	Set a window to the region where you want input to occur.
X		Usually this is one line at the top or bottom of the screen.
X	2.	Call dpyread to read the input.
X	If the prompt string pointer is not NULL, then the prompt string will
X	appear at the top of the window, followed by the data typed by the user.
X	To display the user's input without any prompt, use a pointer to a
X	null string.  If the prompt pointer is NULL, then no terminal I/O at
X	all will be performed (useful when input is from a script or file).
X	The buf and count specify the area in the calling program where the
X	data being read is stored.  The data will be what was typed by the
X	user, not what is seen on the screen (for example, control characters
X	appear on the screen as ^X, but appear in the buffer as themselves).
X	If more data is typed than fits in the window, the data in the window
X	is automatically scrolled to keep the current input location visible.
X	Routine is a function variable which specifies a routine which will
X	provide the input characters for dpy.  The routine is called with the
X	previous character read (-1 on the first call).  It returns the
X	next character read, or -1 to return from dpyread.  Providing the
X	previous character as an argument allows a routine to easily return
X	a break character as input, and then end the input on the next call.
X	If 0 is supplied as a routine, a default routine will be used which
X	reads from the standard input until an end of file or newline is typed
X	(which is included in the buffer).  If the character count is exceeded,
X	dpyread will warn the user with a bell and discard further input.
X	Dpyread returns the number of characters read into the buffer, which
X	is not guaranteed to contain a terminating null or newline character.
X
Xdpywindow(minrow, maxrow, mincol, maxcol)
X	Specifies a rectangle where characters will be placed in the future
X	screen image, and sets the current write location to the top left
X	corner of the rectangle.  The rectangle is specified by the minimum
X	and maximum row numbers, and minimum and maximum column numbers,
X	where the top left corner of the screen is row 0 and column 0.
X	The coordinates are specified in absolute screen coordinates, and
X	negative numbers specify row or column numbers from the bottom or
X	right edges of the screen.  For example, dpywindow(0, -1, 0, -1)
X	defines a window which is the whole screen.  Returns nonzero if the
X	coordinates are illegal.
X
X
XFinal hints:
X
XA window can be filled with a background character by simply writing that
Xcharacter to the window until a nonzero return value is obtained, meaning
Xthe window is full.
X
XIf a region of the screen is never changed (such as a help text), then that
Xregion should be in its own window.  Then it only needs to be written once.
X
XThe terminal size can be found after calling dpyinit by simply calling
Xdpymove(-1, -1) to move to the lower right of the screen, and then calling
Xdpygetrow and dpygetcol to return the row and column numbers.
X
XWhile writing data to the window, dpygetrow and dpygetcol are useful to
Xremember the location of a particular position in the window, so that
Xthe terminal cursor can be positioned back to that location when all the
Xdata is written.  In this way, you don't have worry about line wrapping
Xand tab and other control character expansions when computing how to
Xposition the cursor on a particular character.
//E*O*F dpy.doc//
echo x - makefile
sed -e 's/^X//' > "makefile" << '//E*O*F makefile//'
X# @(#)makefile	1.13	1/28/85
X
X.SUFFIXES: .c .o .s
X
XCC = cc
XCFLAGS = -O
XAS = as
XRANLIB = ranlib
XLIBDIR = /usr/lib
X
XCFILES = dpy.c dpymove.c dpyplace.c dpyget.c dpyread.c dpywindow.c
XOFILES = dpy.o dpymove.o dpyplace.o dpyget.o dpyread.o dpywindow.o
XSOURCES = ${CFILES} dpy.h vaxsubs.s m16subs.s gensubs.c
X
X# Machine dependent assembly routines.  Define MACHINEFILES appropriately
X# to select the target machine.  Gensubs is a portable version of the
X# subroutines applicable to any machine (but slower than the assembly ones).
X
XGENFILES = gensubs.o		# generic subroutines
XM16FILES = m16subs.o		# 32032 subroutines
XVAXFILES = vaxsubs.o		# VAX subroutines
XMACHINEFILES = ${VAXFILES}	# subroutines to be used
X
X
Xlibdpy.a: ${OFILES} ${MACHINEFILES}
X	ar rc libdpy.a ${OFILES} ${MACHINEFILES}
X	${RANLIB} libdpy.a
X
Xsources: ${SOURCES}
X
X${SOURCES}:
X	sccs get $@
X
X${OFILES}: dpy.h
X
Xinstall: libdpy.a
X	cp libdpy.a ${LIBDIR}
X	${RANLIB} ${LIBDIR}/libdpy.a
X	chmod 644 ${LIBDIR}/libdpy.a
X
Xclean:
X	rm -f *.o libdpy.a
X
X.s.o:
X	${AS} -o $*.o $*.s
X
X.c.o:
X	${CC} -c ${CFLAGS} $*.c
//E*O*F makefile//
echo x - test1.c
sed -e 's/^X//' > "test1.c" << '//E*O*F test1.c//'
X/*
X * Example program.  Randomly fill up the screen with numbers until
X * it all turns to asterisks.
X */
X
Xmain()
X{
X	register int row, col, ch;
X	register int rows, cols;
X
X	if (dpyinit(0, 0, 0)) exit(1);
X	dpymove(-1, -1);
X	rows = dpygetrow() + 1;
X	cols = dpygetcol() + 1;
X	dpyhome();
X	while (1) {
X		dpyupdate();
X		row = random() % rows;
X		col = random() % cols;
X		ch = dpyget(row, col);
X		if (ch == ' ') ch = '1';
X		else if (ch == '9') ch = '*';
X		else if (ch != '*') ch++;
X		dpyplace(row, col, ch);
X	}
X}
//E*O*F test1.c//
echo x - test2.c
sed -e 's/^X//' > "test2.c" << '//E*O*F test2.c//'
X/*
X * Example program.  Split the screen into three windows, input using the
X * top window until an escape is typed, and show it in the bottom window.
X * The middle window is just a border.  Continue until a ^E is typed.
X */
X
X#include <sgtty.h>
X#define	BOARDER	10		/* row for boarder window */
X#define	BUFSIZE	1000		/* maximum chars which can be input */
X#define	ESC	'\033'		/* escape character */
X#define	QUIT	'\005'		/* quit character (^E) */
X
Xint	grabchar();		/* routine to read tty chars */
X
Xmain()
X{
X	register int	i;		/* character count */
X	char	buf[BUFSIZE];		/* input buffer */
X
X	if (dpyinit(0, CBREAK, ECHO)) exit(1);
X	dpywindow(BOARDER, BOARDER, 0, -1);
X	while (dpywrite("-----", 5) == 0) ;
X	while (1) {
X		dpywindow(0, BOARDER - 1, 0, -1);
X		i = dpyread("Input: ", grabchar, buf, sizeof(buf));
X		if ((i > 0) && (buf[i-1] == QUIT)) break;
X		dpywindow(BOARDER + 1, -1, 0, -1);
X		dpyprintf("Read %d chars:\n", i);
X		dpywrite(buf, i);
X		dpyclearwindow();
X		dpyupdate();
X	}
X	dpyclose();
X}
X
X
X/*
X * Read next char from tty, quitting on an end of file or escape character.
X * The escape character is removed from the buffer, but the end of file
X * character is kept.
X */
Xgrabchar(oldch)
X{
X	unsigned char	newch;
X
X	if ((oldch == QUIT) || (read(0, &newch, 1) != 1) || (newch == ESC))
X		return(-1);
X	return(newch);
X}
//E*O*F test2.c//
echo done

dbell@daisy.UUCP (David I. Bell) (01/29/85)

This is part 2 of the dpy sources (the main guts!)

#---Cut here and place in it's own directory, then feed to Bourne shell---
# This is a shell archive.  Remove anything before this line, then
# unpack it by saving it in a file and typing "sh file".  (Files
# unpacked will be owned by you and have default permissions.)
# This archive contains:
#   dpy.c (15780 chars)
#   dpyget.c (1117 chars)
#   dpymove.c (1069 chars)
#   dpyplace.c (1297 chars)
#   dpyread.c (3572 chars)
#   dpywindow.c (1170 chars)
#   dpy.h (2452 chars)
#   gensubs.c (1183 chars)
#   m16subs.s (812 chars)
#   vaxsubs.s (332 chars)
#
echo x - dpy.c
sed -e 's/^X//' > "dpy.c" << '//E*O*F dpy.c//'
Xstatic char *sccsid = "@(#)dpy.c	1.41	1/28/85";
Xstatic char *cpyrid = "@(#)Copyright (C) 1985 by D Bell";
X
X
X/*
X * Different curses package (by David I. Bell).
X * These dpy module sources are in the public domain, and can be copied
X * or used as desired, with the following restrictions:
X * 1.	All copyright notices (and this notice) must be preserved.
X * 2.	The dpy sources (even if modified) cannot be sold for profit.
X * 3.	If any sources are modified, a sentence must exist by the
X *	copyright notice of each modified source file which says that
X *	the file has been modified.
X */
X
X
X#include <stdio.h>		/* standard I/O */
X#include <signal.h>		/* signals */
X#include "dpy.h"		/* window definitions */
X
X#define	STDIN	0		/* standard input */
X#define	STDOUT	1		/* standard output */
X#define	DEL	0177		/* delete character */
X#define	EOL	'\n'		/* end of line character */
X#define	RET	'\r'		/* return character */
X#define	BS	'\b'		/* backspace character */
X#define	TAB	'\t'		/* tab character */
X#define	SPACE	' '		/* space character */
X#define	INTSIZ	(sizeof(int))
X
Xextern	short	ospeed;		/* output speed for tputs to use */
Xstruct	window	window;		/* the window */
Xstatic	int	dpytputs();	/* called by tputs to type to terminal */
Xstatic	int	dpysputs();	/* called by tputs to save characters */
Xint	dpystop();		/* stop routine */
Xchar	*tgetstr();		/* return termcap string */
Xchar	*malloc();		/* allocate memory */
Xchar	*getenv();		/* return environment variable */
X
X
X/* Initialize the window structure.  Returns nonzero on failure with
X * a message already typed.  The ttytype argument is the terminal type
X * string, or NULL if the TERM environment variable is to be used.
X * Modeset and modeclear are changes to make for the terminal mode flags.
X */
Xdpyinit(ttytype, modeset, modeclear)
X	register char	*ttytype;	/* terminal type, or NULL for default */
X{
X	register struct	window	*wp;	/* window pointer */
X	register char	*cp;		/* character pointer */
X	register char	*sp;		/* pointer for spaces */
X	register int	size;		/* size of character array */
X
X	wp = &window;
X	wp->inited = 0;
X	wp->output = 0;
X	if (ttytype == NULL) {
X		ttytype = getenv("TERM");
X		if (ttytype == NULL) {
X			fprintf(stderr, "TERM not defined\n");
X			return(1);
X		}
X	}
X	size = tgetent(wp->tdata, ttytype);
X	if (size <= 0) {
X		fprintf(stderr, size ? "cannot open termcap file"
X			: "unknown terminal type %s\n", ttytype);
X		return(1);
X	}
X	wp->oldttyblk0.sg_erase = CERASE;	/* in case stdin is not a tty */
X	wp->oldttyblk0.sg_kill = CKILL;
X	wp->tchars.t_eofc = CEOF;
X	wp->ltchars.t_rprntc = CRPRNT;
X	wp->ltchars.t_werasc = CWERASE;
X	wp->ltchars.t_lnextc = CLNEXT;
X	wp->oldttyblk1.sg_ospeed = 0;
X	ioctl(STDIN, TIOCGETC, &wp->tchars);	/* collect terminal info */
X	ioctl(STDIN, TIOCGLTC, &wp->ltchars);
X	ioctl(STDIN, TIOCGETP, &wp->oldttyblk0);
X	ioctl(STDOUT, TIOCGETP, &wp->oldttyblk1);
X	ospeed = wp->oldttyblk1.sg_ospeed;	/* save speed for tputs */
X	wp->nrows = tgetnum("li");
X	wp->ncols = tgetnum("co");
X	wp->tptr = wp->tbuf;
X	wp->tc_am = tgetflag("am");
X	wp->tc_ho = tgetstr("ho", &wp->tptr);
X	wp->tc_ce = tgetstr("ce", &wp->tptr);
X	wp->tc_cd = tgetstr("cd", &wp->tptr);
X	wp->tc_cm = tgetstr("cm", &wp->tptr);
X	if ((wp->nrows <= 0) || (wp->ncols <= 0) || (wp->tc_ce == NULL)
X		|| (wp->tc_cd == NULL) || (wp->tc_cm == NULL)) {
X			fprintf(stderr, "missing termcap entry\n");
X			return(1);
X	}
X	sp = wp->tptr;		/* apply padding to clear screen string */
X	tputs(wp->tc_cd, wp->nrows, dpysputs);
X	*wp->tptr++ = NULL;
X	wp->tc_cd = sp;
X	sp = wp->tptr;		/* and to clear line string */
X	tputs(wp->tc_ce, 1, dpysputs);
X	*wp->tptr++ = NULL;
X	wp->tc_ce = sp;
X	if (wp->tc_ho == NULL) {	/* make home up string if not defined */
X		wp->tc_ho = wp->tptr;
X		tputs(tgoto(wp->tc_cm, 0, 0), 1, dpysputs);
X		*wp->tptr++ = NULL;
X	}
X	wp->delta = (wp->ncols + INTSIZ) &~ (INTSIZ-1);	/* round up */
X	size = wp->nrows * wp->delta;
X	cp = malloc(2 * (size + INTSIZ));
X	if (cp == NULL) {
X		fprintf(stderr, "not enough memory for screen data\n");
X		return(1);
X	}
X	wp->begdata = cp;
X	wp->enddata = cp + size;
X	wp->begwin = cp;
X	wp->endwin = cp + size - wp->delta;
X	wp->begrow = cp;
X	wp->endrow = cp + wp->ncols;
X	wp->cp = cp;
X	wp->screen = cp + size + INTSIZ;
X	for (sp = cp + (2 * (size + INTSIZ)) - 1; sp >= cp; sp--) *sp = SPACE;
X	*((int *)(cp + size)) = 0;	/* terminate end of screens */
X	*((int *)(wp->screen + size)) = 0;
X	wp->currow = 0;
X	wp->curcol = 0;
X	wp->noctrl = 0;
X	wp->nocrlf = 0;
X	wp->nomove = 0;
X	wp->scroll = 0;
X	wp->full = 0;
X	wp->tabsize = 8;
X	wp->begchange = wp->enddata;
X	wp->endchange = wp->begdata;
X	wp->newttyblk0 = wp->oldttyblk0;	/* set new tty modes */
X	wp->newttyblk1 = wp->oldttyblk1;
X	wp->newttyblk0.sg_flags |= modeset;
X	wp->newttyblk0.sg_flags &= ~modeclear;
X	wp->newttyblk1.sg_flags |= modeset;
X	wp->newttyblk1.sg_flags &= ~(modeclear | XTABS);
X	wp->inited = 1;
X	signal(SIGTSTP, dpystop);
X	ioctl(STDIN, TIOCSETP, &wp->newttyblk0);
X	ioctl(STDOUT, TIOCSETP, &wp->newttyblk1);
X	return(0);
X}
X
X
X/* Terminate the window, home down to the bottom of the screen, and reset
X * the terminal modes to their original state.
X */
Xdpyclose()
X{
X	register struct	window	*wp;	/* window pointer */
X
X	wp = &window;
X	if (wp->inited) {
X		wp->inited = 0;
X		if (wp->output) {
X			domove(wp->nrows - 1, 0, NULL);
X			fputs(wp->tc_ce, stdout);
X			fflush(stdout);
X		}
X		free(wp->begdata);
X		ioctl(STDIN, TIOCSETP, &wp->oldttyblk0);
X		ioctl(STDOUT, TIOCSETP, &wp->oldttyblk1);
X	}
X	return(0);
X}
X
X
X/* Put a given number of characters to the window at the current write location.
X * Certain control characters have effects, others print as ^X or are ignored.
X * Automatic wrapping to the next line is possible, and scrolling when the last
X * line is full. Returns nonzero if the window cannot hold the whole buffer.
X */
Xdpywrite(buf, count)
X	register char	*buf;		/* buffer address */
X	int	count;			/* number of characters */
X{
X	register struct	window	*wp;	/* window pointer */
X	register char	*endbuf;	/* end of buffer to write */
X	register char	*cp;		/* current character pointer */
X	register int	ch;		/* character to store */
X
X	wp = &window;
X	if (wp->full) return(1);
X	cp = wp->cp;
X	if (cp < wp->begchange) wp->begchange = cp;
X	for (endbuf = buf + count; buf < endbuf; buf++) {
X		ch = *buf;
X		if (ch < ' ') {			/* control character */
X			if (ch == EOL) {	/* new line */
X				clear(cp, wp->endrow);
X				if (cp >= wp->endwin) {	/* window full */
X					wp->endchange = wp->endrow;
X					if (wp->scroll == 0) {
X						wp->full = 1;
X						wp->cp = wp->begrow;
X						return(1);
X					}
X					wp->cp = cp;
X					dpyscroll();
X					cp = wp->begrow;
X					continue;
X				}
X				wp->begrow += wp->delta;
X				wp->endrow += wp->delta;
X				cp = wp->begrow;
X				continue;
X			}
X			if (ch == TAB) {	/* tab */
X				wp->cp = cp;
X				do {
X					if (dpywrite(" ", 1)) return(1);
X				} while ((wp->cp - wp->begrow) % wp->tabsize);
X				cp = wp->cp;
X				continue;
X			}
X			if (ch == BS) {		/* backspace */
X				if (cp > wp->begrow) cp--;
X				continue;
X			}
X			if (ch == RET) {	/* return character */
X				cp = wp->begrow;
X				continue;
X			}
X			/*
X			 * Obscure control character, show as ^X
X			 */
X			if (wp->noctrl) continue;
X			wp->cp = cp;
X			if (dpywrite("^", 1) || dpychar(ch + '@')) return(1);
X			cp = wp->cp;
X			continue;
X		}
X		if (ch == DEL) {		/* delete character */
X			if (wp->noctrl) continue;
X			wp->cp = cp;
X			if (dpywrite("^?", 2)) return(1);
X			cp = wp->cp;
X			continue;
X		}
X		/*
X		 * Normal printing character
X		 */
X		if (cp >= wp->endrow) {		/* end of row, see if do crlf */
X			wp->cp = cp;
X			if (cp > wp->endchange) wp->endchange = cp;
X			if (wp->nocrlf) return(1);
X			if (cp >= wp->endwin) {
X				if (wp->scroll == 0) return(1);
X				dpyscroll();
X				cp = wp->begrow;
X				*cp++ = ch;
X				continue;
X			}
X			wp->begrow += wp->delta;
X			wp->endrow += wp->delta;
X			cp = wp->begrow;
X		}
X		*cp++ = ch;
X	}
X	wp->cp = cp;
X	if (cp > wp->endchange) wp->endchange = cp;
X	return(0);
X}
X
X
X/* Put a single character to the window.
X * Returns nonzero if full.
X */
Xdpychar(ch)
X	char	ch;
X{
X	return(dpywrite(&ch, 1));
X}
X
X
X/* Put a null-terminated string to the window.
X * Returns nonzero if full.
X */
Xdpystr(str)
X	char	*str;
X{
X	return(dpywrite(str, strlen(str)));
X}
X
X
X/* Print a formatted string to the window.  Returns nonzero if full.
X * This routine is a ripped off version of sprintf.  This routine is
X * machine-dependent!!
X */
Xdpyprintf(fmt, args)
X	char	*fmt;			/* format string */
X{
X	struct _iobuf _strbuf;		/* file header */
X	char	buf[5000];		/* data storage */
X
X	_strbuf._flag = _IOWRT+_IOSTRG;
X	_strbuf._ptr = buf;
X	_strbuf._cnt = 32767;
X	_doprnt(fmt, &args, &_strbuf);
X	return(dpywrite(buf, _strbuf._ptr - buf));
X}
X
X
X/* Clear to the end of the current row without changing the write location */
Xdpyclearline()
X{
X	register struct	window	*wp;	/* window pointer */
X	register char	*cp;		/* current character */
X	register char	*endcp;		/* ending character */
X
X	wp = &window;
X	if (wp->full) return;
X	cp = wp->cp;
X	endcp = wp->endrow;
X	if (cp < wp->begchange) wp->begchange = cp;
X	if (endcp > wp->endchange) wp->endchange = cp;
X	clear(cp, endcp);
X}
X
X
X/* Clear to the end of the window without changing the write location */
Xdpyclearwindow()
X{
X	register struct	window	*wp;	/* window pointer */
X	register char	*begcp;		/* beginning character */
X	register char	*cp;		/* current character */
X	register char	*endcp;		/* ending character */
X
X	wp = &window;
X	if (wp->full) return;
X	begcp = wp->begrow;
X	endcp = wp->endrow;
X	cp = wp->cp;
X	if (cp < wp->begchange) wp->begchange = cp;
X	while (1) {
X		clear(cp, endcp);
X		if (begcp >= wp->endwin) break;
X		begcp += wp->delta;
X		endcp += wp->delta;
X		cp = begcp;
X	}
X	if (endcp > wp->endchange) wp->endchange = endcp;
X}
X
X
X/* Set the current write position to the top left corner of the window */
Xdpyhome()
X{
X	register struct	window	*wp;	/* window pointer */
X
X	wp = &window;
X	wp->endrow += wp->begwin - wp->begrow;
X	wp->begrow = wp->begwin;
X	wp->cp = wp->begrow;
X	wp->full = 0;
X}
X
X
X/* Scroll the current window upwards a line to make room for more data. */
Xdpyscroll()
X{
X	register struct	window	*wp;	/* window pointer */
X	register char	*currow;	/* beginning of current row */
X	register char	*nextrow;	/* beginning of next row */
X	register int	cols;		/* columns in window */
X
X	wp = &window;
X	cols = wp->endrow - wp->begrow;
X	currow = wp->begwin;
X	nextrow = currow + wp->delta;
X	while (currow < wp->endwin) {		/* move each line up */
X		bcopy(nextrow, currow, cols);
X		currow += wp->delta;
X		nextrow += wp->delta;
X	}
X	clear(currow, currow + cols);		/* clear last line */
X	wp->begchange = wp->begwin;
X	wp->endchange = wp->endwin + cols;
X}
X
X
X/* Return the row number being written to, or -1 if out of the window.
X * The row number is relative to the beginning of the window.
X */
Xdpygetrow()
X{
X	register struct	window	*wp;	/* window pointer */
X
X	wp = &window;
X	if (wp->full) return(-1);
X	return((wp->cp - wp->begwin) / wp->delta);
X}
X
X
X/* Return the column number being written to, or -1 if out of the window.
X * The column number is relative to the current window.
X */
Xdpygetcol()
X{
X	register struct	window	*wp;	/* window pointer */
X
X	wp = &window;
X	if (wp->full) return(-1);
X	if (wp->cp < wp->endrow) return(wp->cp - wp->begrow);
X	if (wp->nocrlf) return(-1);
X	return(0);
X}
X
X
X/* Make the screen match the data as previously written by the user */
Xdpyupdate()
X{
X	register struct	window	*wp;	/* window pointer */
X	register char	*scp;		/* screen character pointer */
X	register char	*cp;		/* current character */
X	register char	*spcp;		/* cp where spaces remain in row */
X	register char	*endrow;	/* end of row */
X	register char	*begrow;	/* beginning of row */
X	register int	row;		/* current row number */
X	int	diff;
X
X	wp = &window;
X	if (wp->output == 0) {		/* first output, clear screen */
X		wp->output = 1;
X		printf("%s%s", wp->tc_ho, wp->tc_cd);
X	}
X	cp = wp->begchange;
X	scp = wp->screen + (cp - wp->begdata);
X	endrow = 0;
X	while (cp < wp->endchange) {	/* look for a difference */
X		diff = strdif(cp, scp, wp->endchange - cp);
X		cp += diff;
X		scp += diff;
X		if (cp >= wp->endchange) break;
X		if (cp >= endrow) {
X			row = (cp - wp->begdata) / wp->delta;
X			begrow = wp->begdata + (row * wp->delta);
X			endrow = begrow + wp->ncols;
X			spcp = endrow - 1;
X			while ((spcp >= begrow) && (*spcp == SPACE))
X				spcp--;
X			spcp++;
X		}
X		domove(row, cp - begrow, begrow);
X		if (cp >= spcp) {		/* clear rest of line */
X			fputs(wp->tc_ce, stdout);
X			while (cp < endrow) {
X				*scp++ = SPACE;
X				cp++;
X			}
X			continue;
X		}
X		putchar(*cp);
X		*scp++ = *cp++;
X		if (++wp->curcol >= wp->ncols) {	/* fixup last column */
X			wp->curcol--;
X			if (wp->tc_am) {
X				wp->currow++;
X				wp->curcol = 0;
X			}
X		}
X	}
X	wp->begchange = wp->enddata;
X	wp->endchange = wp->begdata;
X	if (wp->nomove == 0) dpycursor();
X	fflush(stdout);
X}
X
X
X/* Set the terminal cursor at the current write location.
X * If the window is full, the cursor is placed at the front of the
X * last line in the window.  If lines are not being wrapped and the
X * line is full, the cursor is placed at the end of the line.
X * Otherwise, the cursor is placed at the location being written to next.
X */
Xstatic
Xdpycursor()
X{
X	register struct	window	*wp;	/* window pointer */
X	register char	*cp;		/* current write location */
X	register char	*begrow;	/* beginning of current row */
X	register int	row;		/* row number */
X
X	wp = &window;
X	cp = wp->cp;
X	if (wp->full)
X		cp = wp->endwin;
X	else if (cp >= wp->endrow) {
X		if (wp->nocrlf || (wp->begrow >= wp->endwin))
X			cp = wp->endrow - 1;
X		else
X			cp = wp->begrow + wp->delta;
X	}
X	row = (cp - wp->begdata) / wp->delta;
X	begrow = wp->begdata + (row * wp->delta);
X	domove(row, cp - begrow, begrow);
X}
X
X
X/* Subroutine to move to the given location on the screen.  The third argument
X * is a pointer to beginning of the desired row in case we find it is faster
X * to type the intervening characters.  If NULL, we must use addressing.
X */
Xstatic
Xdomove(row, col, cp)
X	register int	row;		/* desired row */
X	register int	col;		/* desired column */
X	register char	*cp;		/* data on desired row */
X{
X	register struct	window	*wp;	/* window structure */
X
X	wp = &window;
X	if (cp && (row == wp->currow) && (col >= wp->curcol)
X		&& (col < wp->curcol + 6)) {		/* a few ahead */
X			cp += wp->curcol;
X			while (wp->curcol < col) {
X				putchar(*cp);
X				cp++;
X				wp->curcol++;
X			}
X			return;
X	}
X	if ((col == 0) && (row == wp->currow + 1)) {	/* next row */
X		putchar('\n');
X		wp->currow++;
X		wp->curcol = 0;
X		return;
X	}
X	tputs(tgoto(wp->tc_cm, col, row), 1, dpytputs);	/* arbitrary */
X	wp->currow = row;
X	wp->curcol = col;
X}
X
X
X/* Local routine called by tputs to print a character */
Xstatic
Xdpytputs(ch)
X	char	ch;
X{
X	putchar(ch);
X}
X
X
X/* Local routine called by tputs to save a character */
Xstatic
Xdpysputs(ch)
X	char	ch;
X{
X	*window.tptr++ = ch;
X}
X
X
X/* Redraw the screen to fix glitches */
Xdpyredraw()
X{
X	register struct	window	*wp;	/* window pointer */
X	register char	*cp;		/* current character */
X	register char	*endcp;		/* ending character */
X
X	wp = &window;
X	cp = wp->screen;
X	endcp = cp + (wp->nrows * wp->delta);
X	clear(cp, endcp);
X	wp->currow = 0;
X	wp->curcol = 0;
X	wp->begchange = wp->begdata;
X	wp->endchange = wp->enddata;
X	printf("%s%s", wp->tc_ho, wp->tc_cd);
X	dpyupdate();
X}
X
X
X/* Routine called on a terminal stop signal.  Restore the original terminal
X * state, home down to the bottom, and really stop.  If continued, restore
X * the new terminal state and redraw the screen.
X */
Xdpystop()
X{
X	register struct	window	*wp;	/* window pointer */
X
X	wp = &window;
X	if (wp->output) {
X		domove(wp->nrows - 1, 0, NULL);
X		fflush(stdout);
X	}
X	ioctl(STDIN, TIOCSETP, &wp->oldttyblk0);
X	ioctl(STDOUT, TIOCSETP, &wp->oldttyblk1);
X	kill(getpid(), SIGSTOP);	/* really stop */
X	ioctl(STDIN, TIOCSETP, &wp->newttyblk0);
X	ioctl(STDOUT, TIOCSETP, &wp->newttyblk1);
X	if (wp->output) dpyredraw();
X}
//E*O*F dpy.c//
echo x - dpyget.c
sed -e 's/^X//' > "dpyget.c" << '//E*O*F dpyget.c//'
X#ifdef SCCS
Xstatic char *sccsid = "@(#)dpyget.c	1.1	1/28/85";
Xstatic char *cpyrid = "@(#)Copyright (C) 1985 by D Bell";
X#endif
X
X#include "dpy.h"
X
X/* Return the character which is at the specified location in the current
X * window.  The character returned is the one in our internal screen image,
X * not what is actually on the screen (these will be identical if dpyupdate
X * was just called).  Returns negative if the coordinates are illegal.
X */
Xdpyget(row, col)
X	register int	row;		/* row to get character from */
X	register int	col;		/* column to get character from */
X{
X	register struct	window	*wp;	/* window pointer */
X	register char	*cp;		/* character pointer */
X	register int	winrows;	/* number of rows in window */
X	register int	wincols;	/* number of columns in window */
X
X	wp = &window;
X	winrows = ((wp->endwin - wp->begwin) / wp->delta) + 1;
X	wincols = wp->endrow - wp->begrow;
X	if (row < 0) row += winrows;
X	if (col < 0) col += wincols;
X	if (((unsigned)row >= winrows) || ((unsigned)col >= wincols)) {
X		return(-1);		/* out of window */
X	}
X	cp = wp->begwin + (row * wp->delta) + col;
X	return(*cp & 0xff);
X}
//E*O*F dpyget.c//
echo x - dpymove.c
sed -e 's/^X//' > "dpymove.c" << '//E*O*F dpymove.c//'
X#ifdef SCCS
Xstatic char *sccsid = "@(#)dpymove.c	1.3	1/17/85";
Xstatic char *cpyrid = "@(#)Copyright (C) 1985 by D Bell";
X#endif
X
X#include "dpy.h"
X
X/* Set the current write location to the given row and column.
X * The position given is relative to the current window.
X * Negative numbers indicate backwards from last row or column.
X * Returns nonzero if arguments are out of bounds.
X */
Xdpymove(row, col)
X	register int	row;		/* desired row number */
X	register int	col;		/* desired column number */
X{
X	register struct	window	*wp;	/* window pointer */
X	register int	winrows;	/* number of rows in window */
X	register int	wincols;	/* number of columns in window */
X
X	wp = &window;
X	winrows = ((wp->endwin - wp->begwin) / wp->delta) + 1;
X	wincols = wp->endrow - wp->begrow;
X	if (row < 0) row += winrows;
X	if (col < 0) col += wincols;
X	if (((unsigned)row >= winrows) || ((unsigned)col >= wincols)) {
X		return(1);		/* out of window */
X	}
X	wp->begrow = wp->begwin + (row * wp->delta);
X	wp->endrow = wp->begrow + wincols;
X	wp->cp = wp->begrow + col;
X	wp->full = 0;
X	return(0);
X}
//E*O*F dpymove.c//
echo x - dpyplace.c
sed -e 's/^X//' > "dpyplace.c" << '//E*O*F dpyplace.c//'
X#ifdef SCCS
Xstatic char *sccsid = "@(#)dpyplace.c	1.5	1/28/85";
Xstatic char *cpyrid = "@(#)Copyright (C) 1985 by D Bell";
X#endif
X
X#include "dpy.h"
X
X/* Place a single character to the window at a particular location.
X * The change will not be seen until a call to dpyupdate.
X * The current write location is unaffected.
X * Returns nonzero if coordinates are illegal.
X * The coordinates are relative to the current window.
X */
Xdpyplace(row, col, ch)
X	register int	row;		/* row to place character at */
X	register int	col;		/* column to place character at */
X	char	ch;			/* character to be placed */
X{
X	register struct	window	*wp;	/* window pointer */
X	register char	*cp;		/* character pointer */
X	register int	winrows;	/* number of rows in window */
X	register int	wincols;	/* number of columns in window */
X
X	wp = &window;
X	winrows = ((wp->endwin - wp->begwin) / wp->delta) + 1;
X	wincols = wp->endrow - wp->begrow;
X	if (row < 0) row += winrows;
X	if (col < 0) col += wincols;
X	if (((unsigned)row >= winrows) || ((unsigned)col >= wincols)) {
X		return(1);		/* out of window */
X	}
X	cp = wp->begwin + (row * wp->delta) + col;
X	if (*cp != ch) {		/* do only if char needs changing */
X		if (cp < wp->begchange) wp->begchange = cp;
X		*cp++ = ch;
X		if (cp > wp->endchange) wp->endchange = cp;
X	}
X	return(0);
X}
//E*O*F dpyplace.c//
echo x - dpyread.c
sed -e 's/^X//' > "dpyread.c" << '//E*O*F dpyread.c//'
X#ifdef SCCS
Xstatic char *sccsid = "@(#)dpyread.c	1.11	1/27/85";
Xstatic char *cpyrid = "@(#)Copyright (C) 1985 by D Bell";
X#endif
X
X#define	STDIN	0		/* standard input */
X#include "dpy.h"		/* window definitions */
X
Xstatic int readline();		/* default read routine */
X
X/* Read some input while possibly showing it in the current window.
X * If the prompt string is NULL, then editing is performed without
X * any windowing activity (useful when reading commands from scripts).
X * Otherwise, the prompt is shown in the window along with any input.
X * The given routine is called for each character, with an argument
X * which is the previous character (or -1 on the first call).
X * The routine returns the next input character, or -1 to stop reading.
X * A null routine defaults to one which reads until an end of line.
X * Scrolling of the window is automatically performed when necessary.
X * Editing of the input is handled.  If the buffer fills up, the user
X * is warned with beeps and further input is ignored.
X * Returns number of bytes of data read.
X */
Xdpyread(prompt, routine, buf, count)
X	register char	*prompt;	/* prompt string (if any) */
X	int	(*routine)();		/* routine to call to get character */
X	register char	*buf;		/* address of the storage buffer */
X	int	count;			/* maximum number of bytes allowed */
X{
X	register struct	window	*wp;	/* window pointer */
X	register int	ch;		/* character which was read */
X	register char	*bp;		/* current buffer pointer location */
X	char	*endbp;			/* end of buffer */
X	char	redraw;			/* need to redisplay input */
X	int	promptlen;		/* length of prompt string */
X
X	wp = &window;
X	promptlen = 0;
X	if (prompt) promptlen = strlen(prompt);
X	if ((int)routine == 0) routine = readline;
X	bp = buf;
X	endbp = bp + count - 1;
X	redraw = 1;
X	ch = -1;
X	wp->scroll |= 0x80;
X	while (1) {
X		if (prompt && redraw) {		/* recompute window data */
X			redraw = 0;
X			dpyhome();
X			dpywrite(prompt, promptlen);
X			dpywrite(buf, bp - buf);
X			dpyclearwindow();
X		}
X		if (prompt) dpyupdate();
X		ch = routine(ch);
X		if (ch < 0) {				/* end of file */
X			wp->scroll &= ~0x80;
X			return(bp - buf);
X		}
X		if (ch == wp->ltchars.t_lnextc) {	/* literal input */
X			ch = routine(ch);
X			if (ch < 0) {
X				wp->scroll &= ~0x80;
X				return(bp - buf);
X			}
X			if (bp >= endbp) {		/* buffer is full */
X				write(1, "\07", 1);
X				continue;
X			}
X			*bp = ch;
X			if (prompt) dpywrite(bp, 1);
X			bp++;
X			continue;
X		}
X		if (ch == wp->tchars.t_eofc) {		/* end of file */
X			wp->scroll &= ~0x80;
X			return(bp - buf);
X		}
X		if (ch == wp->oldttyblk0.sg_erase) {	/* character erase */
X			if (bp <= buf) continue;
X			bp--;
X			redraw = 1;
X			continue;
X		}
X		if (ch == wp->ltchars.t_werasc) {	/* word erase */
X			if (bp <= buf) continue;
X			while ((bp > buf) && ((bp[-1] == '\n')
X				|| (bp[-1] == ' ') || (bp[-1] == '\t'))) bp--;
X			while ((bp > buf) && (bp[-1] != '\n')
X				&& (bp[-1] != ' ') && (bp[-1] != '\t')) bp--;
X			redraw = 1;
X			continue;
X		}
X		if (ch == wp->oldttyblk0.sg_kill) {	/* line erase */
X			if (bp <= buf) continue;
X			if (bp[-1] == '\n') bp--;
X			while ((bp > buf) && (bp[-1] != '\n')) bp--;
X			redraw = 1;
X			continue;
X		}
X		if (ch == wp->ltchars.t_rprntc) {	/* retype line */
X			if (prompt) dpyredraw();
X			continue;
X		}
X		if (bp >= endbp) {			/* buffer is full */
X			write(1, "\07", 1);
X			continue;
X		}
X		*bp = ch;				/* normal character */
X		if (prompt) dpywrite(bp, 1);
X		bp++;
X	}
X}
X
X
X/* Local routine to read until end of line character is reached */
Xstatic
Xreadline(ch)
X{
X	if ((ch == '\n') || (read(STDIN, &ch, 1) < 1)) return(-1);
X	return(ch & 0xff);
X}
//E*O*F dpyread.c//
echo x - dpywindow.c
sed -e 's/^X//' > "dpywindow.c" << '//E*O*F dpywindow.c//'
X#ifdef SCCS
Xstatic char *sccsid = "@(#)dpywindow.c	1.3	1/17/85";
Xstatic char *cpyrid = "@(#)Copyright (C) 1985 by D Bell";
X#endif
X
X#include "dpy.h"
X
X/* Set the row and column boundaries of the current window.
X * Negative numbers indicate backwards from last row or column.
X * The write location is set to the top left of the window.
X * Returns nonzero if arguments are out of bounds.
X */
Xdpywindow(minrow, maxrow, mincol, maxcol)
X	register int	minrow, maxrow;		/* range of rows */
X	register int	mincol, maxcol;		/* range of columns */
X{
X	register struct	window	*wp;		/* window pointer */
X
X	wp = &window;
X	if (minrow < 0) minrow += wp->nrows;
X	if (maxrow < 0) maxrow += wp->nrows;
X	if (mincol < 0) mincol += wp->ncols;
X	if (maxcol < 0) maxcol += wp->ncols;
X	if (((unsigned) minrow > maxrow)
X		|| ((unsigned) maxrow >= wp->nrows)
X		|| ((unsigned) mincol > maxcol)
X		|| (maxcol >= wp->ncols)) {
X			return(1);		/* illegal */
X	}
X	wp->begwin = wp->begdata + (minrow * wp->delta) + mincol;
X	wp->endwin = wp->begwin + ((maxrow - minrow) * wp->delta);
X	wp->begrow = wp->begwin;
X	wp->endrow = wp->begrow + (maxcol - mincol + 1);
X	wp->cp = wp->begrow;
X	wp->full = 0;
X	return(0);
X}
//E*O*F dpywindow.c//
echo x - dpy.h
sed -e 's/^X//' > "dpy.h" << '//E*O*F dpy.h//'
X/*
X * @(#)dpy.h	1.7	1/22/85
X * @(#)Copyright (C) 1985 by D Bell
X */
X
X#include <sys/ioctl.h>
X
X/* The window structure contains data describing the state of the screen.
X * The following picture shows a typical screen and window, and shows the
X * relationship of each of the character pointers in the structure.
X *
X *	A----------------------|
X *	|                      |
X *	|    C--------|        |
X *	|    |        |        |
X *	|    E     G  |F       |
X *	|    |        |        |
X *	|    D--------|        |
X *	|                      |
X *	|----------------------|
X *	B
X */
Xstruct	window	{
X	char	*begdata;		/* A: beginning of new screen image */
X	char	*enddata;		/* B: end of screen image */
X	char	*begwin;		/* C: beginning of current window */
X	char	*endwin;		/* D: last row of current window */
X	char	*begrow;		/* E: beginning of current row */
X	char	*endrow;		/* F: end of current row */
X	char	*cp;			/* G: current character pointer */
X	char	*begchange;		/* beginning of changed region */
X	char	*endchange;		/* end of changed region */
X	char	*screen;		/* the actual screen image */
X	int	nrows;			/* number of rows on screen */
X	int	ncols;			/* number of columns on screen */
X	int	delta;			/* distance between rows */
X	int	currow;			/* current row column */
X	int	curcol;			/* cursor column column */
X	int	tabsize;		/* current tab size */
X	char	nocrlf;			/* don't do automatic crlfs */
X	char	noctrl;			/* don't show control characters */
X	char	nomove;			/* don't move cursor when done */
X	char	scroll;			/* scroll screen when end reached */
X	char	inited;			/* we are initialized */
X	char	output;			/* we have output to screen */
X	char	full;			/* window is full */
X	char	tc_am;			/* cursor wraps on last column */
X	char	*tc_ho;			/* home capability */
X	char	*tc_ce;			/* clear to end of line */
X	char	*tc_cd;			/* clear to end of display */
X	char	*tc_cm;			/* move cursor */
X	char	*tptr;			/* pointer into termcap strings */
X	struct	sgttyb	oldttyblk0;	/* original tty parameters for stdin */
X	struct	sgttyb	newttyblk0;	/* new terminal parameters for stdin */
X	struct	sgttyb	oldttyblk1;	/* original tty parameters for stdout */
X	struct	sgttyb	newttyblk1;	/* new terminal parameters for stdout */
X	struct	tchars	tchars;		/* terminal characters */
X	struct	ltchars	ltchars;	/* local terminal characters */
X	char	tdata[1024];		/* buffer for termcap data */
X	char	tbuf[200];		/* strings for termcap */
X};
X
Xextern	struct	window	window;		/* window structure */
//E*O*F dpy.h//
echo x - gensubs.c
sed -e 's/^X//' > "gensubs.c" << '//E*O*F gensubs.c//'
X#ifdef SCCS
Xstatic char *sccsid = "@(#)gensubs.c	1.3	1/17/85";
Xstatic char *cpyrid = "@(#)Copyright (C) 1985 by D Bell";
X#endif
X
X/*
X * Generic subroutines usable on any machine.  These subroutines should
X * be replaced by assembly-level routines if possible, to make dpy run
X * as fast as possible.
X */
X
X
X/*
X * Compare two strings of a given length, and return the number of leading
X * bytes which are identical, or the length if the strings are identical.
X * Nulls are not treated specially.  Examples:
X *	strdif("hi mom", "hi pop", 6) returns 3.
X *	strdif("aaaa1", "aaaa2", 2) returns 2.
X */
Xstrdif(s1, s2, len)
X	register char	*s1;		/* first string */
X	register char	*s2;		/* second string */
X{
X	register char	*end;		/* ending character */
X	char	*beg;			/* beginning character */
X
X	beg = s1;
X	end = s1 + len;
X	while ((s1 < end) && (*s1 == *s2)) {
X		s1++;
X		s2++;
X	}
X	return(s1 - beg);
X}
X
X
X
X/*
X * Clear a number of bytes to spaces, from the original character location
X * up to but not including the ending location.
X */
Xclear(beg, end)
X	register char	*beg;		/* beginning of string to clear */
X	register char	*end;		/* end of string to clear */
X{
X	while (beg < end) *beg++ = ' ';
X}
//E*O*F gensubs.c//
echo x - m16subs.s
sed -e 's/^X//' > "m16subs.s" << '//E*O*F m16subs.s//'
X; @(#)m16subs.s	1.4	1/28/85
X; @(#)Copyright (C) 1985 by D Bell
X;
X;machine dependent subroutines for the National 32032 microprocessor.
X;strdif - return number of bytes until two strings differ or count is reached.
X;clear	- from first address up till last address, make memory spaces.
X
X	.program
X
X_strdif::
X	movd	16(sp),r0	;byte count
X	movd	8(sp),r1	;first string
X	movd	12(sp),r2	;second string
X	cmpsb			;compare bytes
X	subd	8(sp),r1	;get length of search
X	movd	r1,r0		;make return value
X	rxp	0		;return
X
X
X_clear::
X	movd	12(sp),r0	;ending address
X	movd	8(sp),r1	;beginning address
X	subd	r1,r0		;compute byte count
X	cmpqd	0,r0		;see if any to do
X	bge	done		;nope
X	addqd	-1,r0		;fix count
X	addr	1(r1),r2	;destination address
X	movb	32,0(r1)	;start with a blank
X	movsb			;fill rest too
Xdone:	rxp	0		;return
X
X	.endseg
//E*O*F m16subs.s//
echo x - vaxsubs.s
sed -e 's/^X//' > "vaxsubs.s" << '//E*O*F vaxsubs.s//'
X# @(#)vaxsubs.s	1.5	1/17/85
X# @(#)Copyright (C) 1985 by D Bell
X
X
X	.text
X	.globl	_strdif
X	.globl	_clear
X
X_strdif:
X	.word	0x0
X	cmpc3	12(ap),*4(ap),*8(ap)	#compare the strings
X	subl3	4(ap),r1,r0		#return difference
X	ret
X
X_clear:
X	.word	0x0
X	subl3	4(ap),8(ap),r0		#number of bytes to fill
X	movc5	$0,0,$32,r0,*4(ap)	#fill the bytes
X	ret
//E*O*F vaxsubs.s//
echo done