15-Dec-85 20:52:35-MST,185524;000000000001
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From: George Jones <george@osu-eddie.uucp>
Newsgroups: net.sources
Subject: MicroEmacs for the Amiga
Message-ID: <1012@osu-eddie.UUCP>
Date: 14 Dec 85 21:31:29 GMT
To:       unix-sources@BRL-TGR.ARPA

This is the source to MicroEmacs for the Amiga.  It is a fairly small Public
Domain Emacs that it beats ED hands down.  It supports multiple windows and 
one keyboard macro.  It is ifdefed to work on lots of different machines.
It is a straight port from IBMland.  I have someone working on using the
blitter to increase the speed of the display, and I have lots of ideas for
things that could be done to ehnance this emacs.  I am willing to play
"keeper-of-the-source" and co-ordinate efforts to enhance it.

So here it is, use it and enjoy.  Contact me if you want to help out
on improving it.

Cheers,
George M. Jones
		
cbosgd!osu-eddie!george (uucpnet)
george@ohio-state.csnet (csnet)
70003,2443 (CompuServe)
+1 (614) 457-8600 (work)
+1 (614) 885-5102 (home)

==============================CUT HERE==============================



==================================================
ansi.c
==================================================
/*
 * The routines in this file provide support for ANSI style terminals
 * over a serial line. The serial I/O services are provided by routines in
 * "termio.c". It compiles into nothing if not an ANSI device.
 */

#include        <stdio.h>
#include        "ed.h"

#if     ANSI

#define NROW    23                      /* Screen size.                 */
#define NCOL    77                      /* Edit if you want to.         */
#define BEL     0x07                    /* BEL character.               */
#define ESC     0x1B                    /* ESC character.               */

extern  int     ttopen();               /* Forward references.          */
extern  int     ttgetc();
extern  int     ttputc();
extern  int     ttflush();
extern  int     ttclose();
extern  int     ansimove();
extern  int     ansieeol();
extern  int     ansieeop();
extern  int     ansibeep();
extern  int     ansiopen();

/*
 * Standard terminal interface dispatch table. Most of the fields point into
 * "termio" code.
 */
TERM    term    = {
        NROW-1,
        NCOL,
        &ansiopen,
        &ttclose,
        &ttgetc,
        &ttputc,
        &ttflush,
        &ansimove,
        &ansieeol,
        &ansieeop,
        &ansibeep
};

ansimove(row, col)
{
        ttputc(ESC);
        ttputc('[');
        ansiparm(row+1);
        ttputc(';');
        ansiparm(col+1);
        ttputc('H');
}

ansieeol()
{
        ttputc(ESC);
        ttputc('[');
        ttputc('K');
}

ansieeop()
{
        ttputc(ESC);
        ttputc('[');
        ttputc('J');
}

ansibeep()
{
        ttputc(BEL);
        ttflush();
}

ansiparm(n)
register int    n;
{
        register int    q;

        q = n/10;
        if (q != 0)
                ansiparm(q);
        ttputc((n%10) + '0');
}

#endif

ansiopen()
{
#if     V7
        register char *cp;
        char *getenv();

        if ((cp = getenv("TERM")) == NULL) {
                puts("Shell variable TERM not defined!");
                exit(1);
        }
        if (strcmp(cp, "vt100") != 0) {
                puts("Terminal type not 'vt100'!");
                exit(1);
        }
#endif
        ttopen();
}

==================================================
basic.c
==================================================
/*
 * The routines in this file move the cursor around on the screen. They
 * compute a new value for the cursor, then adjust ".". The display code
 * always updates the cursor location, so only moves between lines, or
 * functions that adjust the top line in the window and invalidate the
 * framing, are hard.
 */
#include        <stdio.h>
#include        "ed.h"

/*
 * Move the cursor to the
 * beginning of the current line.
 * Trivial.
 */
gotobol(f, n)
{
        curwp->w_doto  = 0;
        return (TRUE);
}

/*
 * Move the cursor backwards by "n" characters. If "n" is less than zero call
 * "forwchar" to actually do the move. Otherwise compute the new cursor
 * location. Error if you try and move out of the buffer. Set the flag if the
 * line pointer for dot changes.
 */
backchar(f, n)
register int    n;
{
        register LINE   *lp;

        if (n < 0)
                return (forwchar(f, -n));
        while (n--) {
                if (curwp->w_doto == 0) {
                        if ((lp=lback(curwp->w_dotp)) == curbp->b_linep)
                                return (FALSE);
                        curwp->w_dotp  = lp;
                        curwp->w_doto  = llength(lp);
                        curwp->w_flag |= WFMOVE;
                } else
                        curwp->w_doto--;
        }
        return (TRUE);
}

/*
 * Move the cursor to the end of the current line. Trivial. No errors.
 */
gotoeol(f, n)
{
        curwp->w_doto  = llength(curwp->w_dotp);
        return (TRUE);
}

/*
 * Move the cursor forwwards by "n" characters. If "n" is less than zero call
 * "backchar" to actually do the move. Otherwise compute the new cursor
 * location, and move ".". Error if you try and move off the end of the
 * buffer. Set the flag if the line pointer for dot changes.
 */
forwchar(f, n)
register int    n;
{
        if (n < 0)
                return (backchar(f, -n));
        while (n--) {
                if (curwp->w_doto == llength(curwp->w_dotp)) {
                        if (curwp->w_dotp == curbp->b_linep)
                                return (FALSE);
                        curwp->w_dotp  = lforw(curwp->w_dotp);
                        curwp->w_doto  = 0;
                        curwp->w_flag |= WFMOVE;
                } else
                        curwp->w_doto++;
        }
        return (TRUE);
}

/*
 * Goto the beginning of the buffer. Massive adjustment of dot. This is
 * considered to be hard motion; it really isn't if the original value of dot
 * is the same as the new value of dot. Normally bound to "M-<".
 */
gotobob(f, n)
{
        curwp->w_dotp  = lforw(curbp->b_linep);
        curwp->w_doto  = 0;
        curwp->w_flag |= WFHARD;
        return (TRUE);
}

/*
 * Move to the end of the buffer. Dot is always put at the end of the file
 * (ZJ). The standard screen code does most of the hard parts of update.
 * Bound to "M->".
 */
gotoeob(f, n)
{
        curwp->w_dotp  = curbp->b_linep;
        curwp->w_doto  = 0;
        curwp->w_flag |= WFHARD;
        return (TRUE);
}

/*
 * Move forward by full lines. If the number of lines to move is less than
 * zero, call the backward line function to actually do it. The last command
 * controls how the goal column is set. Bound to "C-N". No errors are
 * possible.
 */
forwline(f, n)
{
        register LINE   *dlp;

        if (n < 0)
                return (backline(f, -n));
        if ((lastflag&CFCPCN) == 0)             /* Reset goal if last   */
                curgoal = curcol;               /* not C-P or C-N       */
        thisflag |= CFCPCN;
        dlp = curwp->w_dotp;
        while (n-- && dlp!=curbp->b_linep)
                dlp = lforw(dlp);
        curwp->w_dotp  = dlp;
        curwp->w_doto  = getgoal(elp);
        curwp->w_flag |= WFMOVE;
        return (TRUE);
}

/*
 * This function is like "forwline", but goes backwards. The scheme is exactly
 * the same. Check for arguments that are less than zero and call your
 * alternate. Figure out the new line and call "movedot" to perform the
 * motion. No errors are possible. Bound to "C-P".
 */
backline(f, n)
{
        register LINE   *dlp;

        if (n < 0)
                return (forwline(f, -n));
        if ((lastflag&CFCPCN) == 0)             /* Reset goal if the    */
                curgoal = curcol;               /* last isn't C-P, C-N  */
        thisflag |= CFCPCN;
        dlp = curwp->w_dotp;
        while (n-- && lback(dlp)!=curbp->b_linep)
                dlp = lback(dlp);
        curwp->w_dotp  = dlp;
        curwp->w_doto  = getgoal(dlp);
        curwp->w_flag |= WFMOVE;
        return (TRUE);
}

/*
 * This routine, given a pointer to a LINE, and the current cursor goal
 * column, return the best choice for the offset. The offset is returned.
 * Used by "C-N" and "C-P".
 */
getgoal(dlp)
register LINE   *dlp;
{
        register int    c;
        register int    col;
        register int    newcol;
        register int    dbo;

        col = 0;
        dbo = 0;
        while (dbo != llength(dlp)) {
                c = lgetc(dlp, dbo);
                newcol = col;
                if (c == '\t')
                        newcol |= 0x07;
                else if (c<0x20 || c==0x7F)
                        ++newcol;
                ++newcol;
                if (newcol > curgoal)
                        break;
                col = newcol;
                ++dbo;
        }
        return (dbo);
}

/*
 * Scroll forward by a specified number of lines, or by a full page if no
 * argument. Bound to "C-V". The "2" in the arithmetic on the window size is
 * the overlap; this value is the default overlap value in ITS EMACS. Because
 * this zaps the top line in the display window, we have to do a hard update.
 */
forwpage(f, n)
register int    n;
{
        register LINE   *lp;

        if (f == FALSE) {
                n = curwp->w_ntrows - 2;        /* Default scroll.      */
                if (n <= 0)                     /* Forget the overlap   */
                        n = 1;                  /* if tiny window.      */
        } else if (n < 0)
                return (backpage(f, -n));
#if     CVMVAS
        else                                    /* Convert from pages   */
                n *= curwp->w_ntrows;           /* to lines.            */
#endif
        lp = curwp->w_linep;
        while (n-- && lp!=curbp->b_linep)
                lp = lforw(lp);
        curwp->w_linep = lp;
        curwp->w_dotp  = lp;
        curwp->w_doto  = 0;
        curwp->w_flag |= WFHARD;
        return (TRUE);
}

/*
 * This command is like "forwpage", but it goes backwards. The "2", like
 * above, is the overlap between the two windows. The value is from the ITS
 * EMACS manual. Bound to "M-V". We do a hard update for exactly the same
 * reason.
 */
backpage(f, n)
register int    n;
{
        register LINE   *lp;

        if (f == FALSE) {
                n = curwp->w_ntrows - 2;        /* Default scroll.      */
                if (n <= 0)                     /* Don't blow up if the */
                        n = 1;                  /* window is tiny.      */
        } else if (n < 0)
                return (forwpage(f, -n));
#if     CVMVAS
        else                                    /* Convert from pages   */
                n *= curwp->w_ntrows;           /* to lines.            */
#endif
        lp = curwp->w_linep;
        while (n-- && lback(lp)!=curbp->b_linep)
                lp = lback(lp);
        curwp->w_linep = lp;
        curwp->w_dotp  = lp;
        curwp->w_doto  = 0;
        curwp->w_flag |= WFHARD;
        return (TRUE);
}

/*
 * Set the mark in the current window to the value of "." in the window. No
 * errors are possible. Bound to "M-.".
 */
setmark(f, n)
{
        curwp->w_markp = curwp->w_dotp;
        curwp->w_marko = curwp->w_doto;
        mlwrite("[Mark set]");
        return (TRUE);
}

/*
 * Swap the values of "." and "mark" in the current window. This is pretty
 * easy, bacause all of the hard work gets done by the standard routine
 * that moves the mark about. The only possible error is "no mark". Bound to
 * "C-X C-X".
 */
swapmark(f, n)
{
        register LINE   *odotp;
        register int    odoto;

        if (curwp->w_markp == NULL) {
                mlwrite("No mark in this window");
                return (FALSE);
        }
        odotp = curwp->w_dotp;
        odoto = curwp->w_doto;
        curwp->w_dotp  = curwp->w_markp;
        curwp->w_doto  = curwp->w_marko;
        curwp->w_markp = odotp;
        curwp->w_marko = odoto;
        curwp->w_flag |= WFMOVE;
        return (TRUE);
}

==================================================
buffer.c
==================================================
/*
 * Buffer management.
 * Some of the functions are internal,
 * and some are actually attached to user
 * keys. Like everyone else, they set hints
 * for the display system.
 */
#include        <stdio.h>
#include        "ed.h"

/*
 * Attach a buffer to a window. The
 * values of dot and mark come from the buffer
 * if the use count is 0. Otherwise, they come
 * from some other window.
 */
usebuffer(f, n)
{
        register BUFFER *bp;
        register WINDOW *wp;
        register int    s;
        char            bufn[NBUFN];

        if ((s=mlreply("Use buffer: ", bufn, NBUFN)) != TRUE)
                return (s);
        if ((bp=bfind(bufn, TRUE, 0)) == NULL)
                return (FALSE);
        if (--curbp->b_nwnd == 0) {             /* Last use.            */
                curbp->b_dotp  = curwp->w_dotp;
                curbp->b_doto  = curwp->w_doto;
                curbp->b_markp = curwp->w_markp;
                curbp->b_marko = curwp->w_marko;
        }
        curbp = bp;                             /* Switch.              */
        curwp->w_bufp  = bp;
        curwp->w_linep = bp->b_linep;           /* For macros, ignored. */
        curwp->w_flag |= WFMODE|WFFORCE|WFHARD; /* Quite nasty.         */
        if (bp->b_nwnd++ == 0) {                /* First use.           */
                curwp->w_dotp  = bp->b_dotp;
                curwp->w_doto  = bp->b_doto;
                curwp->w_markp = bp->b_markp;
                curwp->w_marko = bp->b_marko;
                return (TRUE);
        }
        wp = wheadp;                            /* Look for old.        */
        while (wp != NULL) {
                if (wp!=curwp && wp->w_bufp==bp) {
                        curwp->w_dotp  = wp->w_dotp;
                        curwp->w_doto  = wp->w_doto;
                        curwp->w_markp = wp->w_markp;
                        curwp->w_marko = wp->w_marko;
                        break;
                }
                wp = wp->w_wndp;
        }
        return (TRUE);
}

/*
 * Dispose of a buffer, by name.
 * Ask for the name. Look it up (don't get too
 * upset if it isn't there at all!). Get quite upset
 * if the buffer is being displayed. Clear the buffer (ask
 * if the buffer has been changed). Then free the header
 * line and the buffer header. Bound to "C-X K".
 */
killbuffer(f, n)
{
        register BUFFER *bp;
        register BUFFER *bp1;
        register BUFFER *bp2;
        register int    s;
        char            bufn[NBUFN];

        if ((s=mlreply("Kill buffer: ", bufn, NBUFN)) != TRUE)
                return (s);
        if ((bp=bfind(bufn, FALSE, 0)) == NULL) /* Easy if unknown.     */
                return (TRUE);
        if (bp->b_nwnd != 0) {                  /* Error if on screen.  */
                mlwrite("Buffer is being displayed");
                return (FALSE);
        }
        if ((s=bclear(bp)) != TRUE)             /* Blow text away.      */
                return (s);
        free((char *) bp->b_linep);             /* Release header line. */
        bp1 = NULL;                             /* Find the header.     */
        bp2 = bheadp;
        while (bp2 != bp) {
                bp1 = bp2;
                bp2 = bp2->b_bufp;
        }
        bp2 = bp2->b_bufp;                      /* Next one in chain.   */
        if (bp1 == NULL)                        /* Unlink it.           */
                bheadp = bp2;
        else
                bp1->b_bufp = bp2;
        free((char *) bp);                      /* Release buffer block */
        return (TRUE);
}

/*
 * List all of the active
 * buffers. First update the special
 * buffer that holds the list. Next make
 * sure at least 1 window is displaying the
 * buffer list, splitting the screen if this
 * is what it takes. Lastly, repaint all of
 * the windows that are displaying the
 * list. Bound to "C-X C-B".
 */
listbuffers(f, n)
{
        register WINDOW *wp;
        register BUFFER *bp;
        register int    s;

        if ((s=makelist()) != TRUE)
                return (s);
        if (blistp->b_nwnd == 0) {              /* Not on screen yet.   */
                if ((wp=wpopup()) == NULL)
                        return (FALSE);
                bp = wp->w_bufp;
                if (--bp->b_nwnd == 0) {
                        bp->b_dotp  = wp->w_dotp;
                        bp->b_doto  = wp->w_doto;
                        bp->b_markp = wp->w_markp;
                        bp->b_marko = wp->w_marko;
                }
                wp->w_bufp  = blistp;
                ++blistp->b_nwnd;
        }
        wp = wheadp;
        while (wp != NULL) {
                if (wp->w_bufp == blistp) {
                        wp->w_linep = lforw(blistp->b_linep);
                        wp->w_dotp  = lforw(blistp->b_linep);
                        wp->w_doto  = 0;
                        wp->w_markp = NULL;
                        wp->w_marko = 0;
                        wp->w_flag |= WFMODE|WFHARD;
                }
                wp = wp->w_wndp;
        }
        return (TRUE);
}

/*
 * This routine rebuilds the
 * text in the special secret buffer
 * that holds the buffer list. It is called
 * by the list buffers command. Return TRUE
 * if everything works. Return FALSE if there
 * is an error (if there is no memory).
 */
makelist()
{
        register char   *cp1;
        register char   *cp2;
        register int    c;
        register BUFFER *bp;
        register LINE   *lp;
        register int    nbytes;
        register int    s;
        register int    type;
        char            b[6+1];
        char            line[128];

        blistp->b_flag &= ~BFCHG;               /* Don't complain!      */
        if ((s=bclear(blistp)) != TRUE)         /* Blow old text away   */
                return (s);
        strcpy(blistp->b_fname, "");
        if (addline("C   Size Buffer           File") == FALSE
        ||  addline("-   ---- ------           ----") == FALSE)
                return (FALSE);
        bp = bheadp;                            /* For all buffers      */
        while (bp != NULL) {
                if ((bp->b_flag&BFTEMP) != 0) { /* Skip magic ones.     */
                        bp = bp->b_bufp;
                        continue;
                }
                cp1 = &line[0];                 /* Start at left edge   */
                if ((bp->b_flag&BFCHG) != 0)    /* "*" if changed       */
                        *cp1++ = '*';
                else
                        *cp1++ = ' ';
                *cp1++ = ' ';                   /* Gap.                 */
                nbytes = 0;                     /* Count bytes in buf.  */
                lp = lforw(bp->b_linep);
                while (lp != bp->b_linep) {
                        nbytes += llength(lp)+1;
                        lp = lforw(lp);
                }
                itoa(b, 6, nbytes);             /* 6 digit buffer size. */
                cp2 = &b[0];
                while ((c = *cp2++) != 0)
                        *cp1++ = c;
                *cp1++ = ' ';                   /* Gap.                 */
                cp2 = &bp->b_bname[0];          /* Buffer name          */
                while ((c = *cp2++) != 0)
                        *cp1++ = c;
                cp2 = &bp->b_fname[0];          /* File name            */
                if (*cp2 != 0) {
                        while (cp1 < &line[1+1+6+1+NBUFN+1])
                                *cp1++ = ' ';           
                        while ((c = *cp2++) != 0) {
                                if (cp1 < &line[128-1])
                                        *cp1++ = c;
                        }
                }
                *cp1 = 0;                       /* Add to the buffer.   */
                if (addline(line) == FALSE)
                        return (FALSE);
                bp = bp->b_bufp;
        }
        return (TRUE);                          /* All done             */
}

itoa(buf, width, num)
register char   buf[];
register int    width;
register int    num;
{
        buf[width] = 0;                         /* End of string.       */
        while (num >= 10) {                     /* Conditional digits.  */
                buf[--width] = (num%10) + '0';
                num /= 10;
        }
        buf[--width] = num + '0';               /* Always 1 digit.      */
        while (width != 0)                      /* Pad with blanks.     */
                buf[--width] = ' ';
}

/*
 * The argument "text" points to
 * a string. Append this line to the
 * buffer list buffer. Handcraft the EOL
 * on the end. Return TRUE if it worked and
 * FALSE if you ran out of room.
 */
addline(text)
char    *text;
{
        register LINE   *lp;
        register int    i;
        register int    ntext;

        ntext = strlen(text);
        if ((lp=lalloc(ntext)) == NULL)
                return (FALSE);
        for (i=0; i<ntext; ++i)
                lputc(lp, i, text[i]);
        blistp->b_linep->l_bp->l_fp = lp;       /* Hook onto the end    */
        lp->l_bp = blistp->b_linep->l_bp;
        blistp->b_linep->l_bp = lp;
        lp->l_fp = blistp->b_linep;
        if (blistp->b_dotp == blistp->b_linep)  /* If "." is at the end */
                blistp->b_dotp = lp;            /* move it to new line  */
        return (TRUE);
}

/*
 * Look through the list of
 * buffers. Return TRUE if there
 * are any changed buffers. Buffers
 * that hold magic internal stuff are
 * not considered; who cares if the
 * list of buffer names is hacked.
 * Return FALSE if no buffers
 * have been changed.
 */
anycb()
{
        register BUFFER *bp;

        bp = bheadp;
        while (bp != NULL) {
                if ((bp->b_flag&BFTEMP)==0 && (bp->b_flag&BFCHG)!=0)
                        return (TRUE);
                bp = bp->b_bufp;
        }
        return (FALSE);
}

/*
 * Find a buffer, by name. Return a pointer
 * to the BUFFER structure associated with it. If
 * the named buffer is found, but is a TEMP buffer (like
 * the buffer list) conplain. If the buffer is not found
 * and the "cflag" is TRUE, create it. The "bflag" is
 * the settings for the flags in in buffer.
 */
BUFFER  *
bfind(bname, cflag, bflag)
register char   *bname;
{
        register BUFFER *bp;
        register LINE   *lp;

        bp = bheadp;
        while (bp != NULL) {
                if (strcmp(bname, bp->b_bname) == 0) {
                        if ((bp->b_flag&BFTEMP) != 0) {
                                mlwrite("Cannot select builtin buffer");
                                return (NULL);
                        }
                        return (bp);
                }
                bp = bp->b_bufp;
        }
        if (cflag != FALSE) {
                if ((bp=(BUFFER *)malloc(sizeof(BUFFER))) == NULL)
                        return (NULL);
                if ((lp=lalloc(0)) == NULL) {
                        free((char *) bp);
                        return (NULL);
                }
                bp->b_bufp  = bheadp;
                bheadp = bp;
                bp->b_dotp  = lp;
                bp->b_doto  = 0;
                bp->b_markp = NULL;
                bp->b_marko = 0;
                bp->b_flag  = bflag;
                bp->b_nwnd  = 0;
                bp->b_linep = lp;
                strcpy(bp->b_fname, "");
                strcpy(bp->b_bname, bname);
                lp->l_fp = lp;
                lp->l_bp = lp;
        }
        return (bp);
}

/*
 * This routine blows away all of the text
 * in a buffer. If the buffer is marked as changed
 * then we ask if it is ok to blow it away; this is
 * to save the user the grief of losing text. The
 * window chain is nearly always wrong if this gets
 * called; the caller must arrange for the updates
 * that are required. Return TRUE if everything
 * looks good.
 */
bclear(bp)
register BUFFER *bp;
{
        register LINE   *lp;
        register int    s;
        
        if ((bp->b_flag&BFTEMP) == 0            /* Not scratch buffer.  */
        && (bp->b_flag&BFCHG) != 0              /* Something changed    */
        && (s=mlyesno("Discard changes")) != TRUE)
                return (s);
        bp->b_flag  &= ~BFCHG;                  /* Not changed          */
        while ((lp=lforw(bp->b_linep)) != bp->b_linep)
                lfree(lp);
        bp->b_dotp  = bp->b_linep;              /* Fix "."              */
        bp->b_doto  = 0;
        bp->b_markp = NULL;                     /* Invalidate "mark"    */
        bp->b_marko = 0;
        return (TRUE);
}

==================================================
display.c
==================================================
/*
 * The functions in this file handle redisplay. There are two halves, the
 * ones that update the virtual display screen, and the ones that make the
 * physical display screen the same as the virtual display screen. These
 * functions use hints that are left in the windows by the commands.
 *
 * REVISION HISTORY:
 *
 * ?    Steve Wilhite, 1-Dec-85
 *      - massive cleanup on code.
 */

#include        <stdio.h>
#include        "ed.h"

#define WFDEBUG 0                       /* Window flag debug. */

typedef struct  VIDEO {
        short   v_flag;                 /* Flags */
        char    v_text[1];              /* Screen data. */
}       VIDEO;

#define VFCHG   0x0001                  /* Changed. */

int     sgarbf  = TRUE;                 /* TRUE if screen is garbage */
int     mpresf  = FALSE;                /* TRUE if message in last line */
int     vtrow   = 0;                    /* Row location of SW cursor */
int     vtcol   = 0;                    /* Column location of SW cursor */
int     ttrow   = HUGE;                 /* Row location of HW cursor */
int     ttcol   = HUGE;                 /* Column location of HW cursor */

VIDEO   **vscreen;                      /* Virtual screen. */
VIDEO   **pscreen;                      /* Physical screen. */

/*
 * Initialize the data structures used by the display code. The edge vectors
 * used to access the screens are set up. The operating system's terminal I/O
 * channel is set up. All the other things get initialized at compile time.
 * The original window has "WFCHG" set, so that it will get completely
 * redrawn on the first call to "update".
 */
vtinit()
{
    register int i;
    register VIDEO *vp;

    (*term.t_open)();
    vscreen = (VIDEO **) malloc(term.t_nrow*sizeof(VIDEO *));

    if (vscreen == NULL)
        exit(1);

    pscreen = (VIDEO **) malloc(term.t_nrow*sizeof(VIDEO *));

    if (pscreen == NULL)
        exit(1);

    for (i = 0; i < term.t_nrow; ++i)
        {
        vp = (VIDEO *) malloc(sizeof(VIDEO)+term.t_ncol);

        if (vp == NULL)
            exit(1);

        vscreen[i] = vp;
        vp = (VIDEO *) malloc(sizeof(VIDEO)+term.t_ncol);

        if (vp == NULL)
            exit(1);

        pscreen[i] = vp;
        }
}

/*
 * Clean up the virtual terminal system, in anticipation for a return to the
 * operating system. Move down to the last line and clear it out (the next
 * system prompt will be written in the line). Shut down the channel to the
 * terminal.
 */
vttidy()
{
    movecursor(term.t_nrow, 0);
    (*term.t_eeol)();
    (*term.t_close)();
}

/*
 * Set the virtual cursor to the specified row and column on the virtual
 * screen. There is no checking for nonsense values; this might be a good
 * idea during the early stages.
 */
vtmove(row, col)
{
    vtrow = row;
    vtcol = col;
}

/*
 * Write a character to the virtual screen. The virtual row and column are
 * updated. If the line is too long put a "$" in the last column. This routine
 * only puts printing characters into the virtual terminal buffers. Only
 * column overflow is checked.
 */
vtputc(c)
    int c;
{
    register VIDEO      *vp;

    vp = vscreen[vtrow];

    if (vtcol >= term.t_ncol)
        vp->v_text[term.t_ncol - 1] = '$';
    else if (c == '\t')
        {
        do
            {
            vtputc(' ');
            }
        while ((vtcol&0x07) != 0);
        }
    else if (c < 0x20 || c == 0x7F)
        {
        vtputc('^');
        vtputc(c ^ 0x40);
        }
    else
        vp->v_text[vtcol++] = c;                
}

/*
 * Erase from the end of the software cursor to the end of the line on which
 * the software cursor is located.
 */
vteeol()
{
    register VIDEO      *vp;

    vp = vscreen[vtrow];
    while (vtcol < term.t_ncol)
        vp->v_text[vtcol++] = ' ';
}

/*
 * Make sure that the display is right. This is a three part process. First,
 * scan through all of the windows looking for dirty ones. Check the framing,
 * and refresh the screen. Second, make sure that "currow" and "curcol" are
 * correct for the current window. Third, make the virtual and physical
 * screens the same.
 */
update()
{
    register LINE *lp;
    register WINDOW *wp;
    register VIDEO *vp1;
    register VIDEO *vp2;
    register int i;
    register int j;
    register int c;

    wp = wheadp;

    while (wp != NULL)
        {
        /* Look at any window with update flags set on. */

        if (wp->w_flag != 0)
            {
            /* If not force reframe, check the framing. */

            if ((wp->w_flag & WFFORCE) == 0)
                {
                lp = wp->w_linep;

                for (i = 0; i < wp->w_ntrows; ++i)
                    {
                    if (lp == wp->w_dotp)
                        goto out;

                    if (lp == wp->w_bufp->b_linep)
                        break;

                    lp = lforw(lp);
                    }
                }

            /* Not acceptable, better compute a new value for the line at the
             * top of the window. Then set the "WFHARD" flag to force full
             * redraw.
             */
            i = wp->w_force;

            if (i > 0)
                {
                --i;

                if (i >= wp->w_ntrows)
                  i = wp->w_ntrows-1;
                }
            else if (i < 0)
                {
                i += wp->w_ntrows;

                if (i < 0)
                    i = 0;
                }
            else
                i = wp->w_ntrows/2;

            lp = wp->w_dotp;

            while (i != 0 && lback(lp) != wp->w_bufp->b_linep)
                {
                --i;
                lp = lback(lp);
                }

            wp->w_linep = lp;
            wp->w_flag |= WFHARD;       /* Force full. */

out:
            /* Try to use reduced update. Mode line update has its own special
             * flag. The fast update is used if the only thing to do is within
             * the line editing.
             */
            lp = wp->w_linep;
            i = wp->w_toprow;

            if ((wp->w_flag & ~WFMODE) == WFEDIT)
                {
                while (lp != wp->w_dotp)
                    {
                    ++i;
                    lp = lforw(lp);
                    }

                vscreen[i]->v_flag |= VFCHG;
                vtmove(i, 0);

                for (j = 0; j < llength(lp); ++j)
                    vtputc(lgetc(lp, j));

                vteeol();
                }
             else if ((wp->w_flag & (WFEDIT | WFHARD)) != 0)
                {
                while (i < wp->w_toprow+wp->w_ntrows)
                    {
                    vscreen[i]->v_flag |= VFCHG;
                    vtmove(i, 0);

                    if (lp != wp->w_bufp->b_linep)
                        {
                        for (j = 0; j < llength(lp); ++j)
                            vtputc(lgetc(lp, j));

                        lp = lforw(lp);
                        }

                    vteeol();
                    ++i;
                    }
                }
#if ~WFDEBUG
            if ((wp->w_flag&WFMODE) != 0)
                modeline(wp);

            wp->w_flag  = 0;
            wp->w_force = 0;
#endif
            }           
#if WFDEBUG
        modeline(wp);
        wp->w_flag =  0;
        wp->w_force = 0;
#endif
        wp = wp->w_wndp;
        }

    /* Always recompute the row and column number of the hardware cursor. This
     * is the only update for simple moves.
     */
    lp = curwp->w_linep;
    currow = curwp->w_toprow;

    while (lp != curwp->w_dotp)
        {
        ++currow;
        lp = lforw(lp);
        }

    curcol = 0;
    i = 0;

    while (i < curwp->w_doto)
        {
        c = lgetc(lp, i++);

        if (c == '\t')
            curcol |= 0x07;
        else if (c < 0x20 || c == 0x7F)
            ++curcol;

        ++curcol;
        }

    if (curcol >= term.t_ncol)          /* Long line. */
        curcol = term.t_ncol-1;

    /* Special hacking if the screen is garbage. Clear the hardware screen,
     * and update your copy to agree with it. Set all the virtual screen
     * change bits, to force a full update.
     */
    if (sgarbf != FALSE)
        {
        for (i = 0; i < term.t_nrow; ++i)
            {
            vscreen[i]->v_flag |= VFCHG;
            vp1 = pscreen[i];
            for (j = 0; j < term.t_ncol; ++j)
                vp1->v_text[j] = ' ';
            }

        movecursor(0, 0);               /* Erase the screen. */
        (*term.t_eeop)();
        sgarbf = FALSE;                 /* Erase-page clears */
        mpresf = FALSE;                 /* the message area. */
        }

    /* Make sure that the physical and virtual displays agree. Unlike before,
     * the "updateline" code is only called with a line that has been updated
     * for sure.
     */
    for (i = 0; i < term.t_nrow; ++i)
        {
        vp1 = vscreen[i];

        if ((vp1->v_flag&VFCHG) != 0)
            {
            vp1->v_flag &= ~VFCHG;
            vp2 = pscreen[i];
            updateline(i, &vp1->v_text[0], &vp2->v_text[0]);
            }
        }

    /* Finally, update the hardware cursor and flush out buffers. */

    movecursor(currow, curcol);
    (*term.t_flush)();
}

/*
 * Update a single line. This does not know how to use insert or delete
 * character sequences; we are using VT52 functionality. Update the physical
 * row and column variables. It does try an exploit erase to end of line. The
 * RAINBOW version of this routine uses fast video.
 */
updateline(row, vline, pline)
    char vline[];
    char pline[];
{
#if RAINBOW
    register char *cp1;
    register char *cp2;
    register int nch;

    cp1 = &vline[0];                    /* Use fast video. */
    cp2 = &pline[0];
    putline(row+1, 1, cp1);
    nch = term.t_ncol;

    do
        {
        *cp2 = *cp1;
        ++cp2;
        ++cp1;
        }
    while (--nch);
#else
    register char *cp1;
    register char *cp2;
    register char *cp3;
    register char *cp4;
    register char *cp5;
    register int nbflag;

    cp1 = &vline[0];                    /* Compute left match.  */
    cp2 = &pline[0];

    while (cp1!=&vline[term.t_ncol] && cp1[0]==cp2[0])
        {
        ++cp1;
        ++cp2;
        }

    /* This can still happen, even though we only call this routine on changed
     * lines. A hard update is always done when a line splits, a massive
     * change is done, or a buffer is displayed twice. This optimizes out most
     * of the excess updating. A lot of computes are used, but these tend to
     * be hard operations that do a lot of update, so I don't really care.
     */
    if (cp1 == &vline[term.t_ncol])             /* All equal. */
        return;

    nbflag = FALSE;
    cp3 = &vline[term.t_ncol];          /* Compute right match. */
    cp4 = &pline[term.t_ncol];

    while (cp3[-1] == cp4[-1])
        {
        --cp3;
        --cp4;
        if (cp3[0] != ' ')              /* Note if any nonblank */
            nbflag = TRUE;              /* in right match. */
        }

    cp5 = cp3;

    if (nbflag == FALSE)                /* Erase to EOL ? */
        {
        while (cp5!=cp1 && cp5[-1]==' ')
            --cp5;

        if (cp3-cp5 <= 3)               /* Use only if erase is */
            cp5 = cp3;                  /* fewer characters. */
        }

    movecursor(row, cp1-&vline[0]);     /* Go to start of line. */

    while (cp1 != cp5)                  /* Ordinary. */
        {
        (*term.t_putchar)(*cp1);
        ++ttcol;
        *cp2++ = *cp1++;
        }

    if (cp5 != cp3)                     /* Erase. */
        {
        (*term.t_eeol)();
        while (cp1 != cp3)
            *cp2++ = *cp1++;
        }
#endif
}

/*
 * Redisplay the mode line for the window pointed to by the "wp". This is the
 * only routine that has any idea of how the modeline is formatted. You can
 * change the modeline format by hacking at this routine. Called by "update"
 * any time there is a dirty window.
 */
modeline(wp)
    WINDOW *wp;
{
    register char *cp;
    register int c;
    register int n;
    register BUFFER *bp;

    n = wp->w_toprow+wp->w_ntrows;              /* Location. */
    vscreen[n]->v_flag |= VFCHG;                /* Redraw next time. */
    vtmove(n, 0);                               /* Seek to right line. */
    vtputc('-');
    bp = wp->w_bufp;

    if ((bp->b_flag&BFCHG) != 0)                /* "*" if changed. */
        vtputc('*');
    else
        vtputc('-');

    n  = 2;
    cp = " MicroEMACS -- ";                     /* Buffer name. */

    while ((c = *cp++) != 0)
        {
        vtputc(c);
        ++n;
        }

    cp = &bp->b_bname[0];

    while ((c = *cp++) != 0)
        {
        vtputc(c);
        ++n;
        }

    vtputc(' ');
    ++n;

    if (bp->b_fname[0] != 0)            /* File name. */
        {
        cp = "-- File: ";

        while ((c = *cp++) != 0)
            {
            vtputc(c);
            ++n;
            }

        cp = &bp->b_fname[0];

        while ((c = *cp++) != 0)
            {
            vtputc(c);
            ++n;
            }

        vtputc(' ');
        ++n;
        }

#if WFDEBUG
    vtputc('-');
    vtputc((wp->w_flag&WFMODE)!=0  ? 'M' : '-');
    vtputc((wp->w_flag&WFHARD)!=0  ? 'H' : '-');
    vtputc((wp->w_flag&WFEDIT)!=0  ? 'E' : '-');
    vtputc((wp->w_flag&WFMOVE)!=0  ? 'V' : '-');
    vtputc((wp->w_flag&WFFORCE)!=0 ? 'F' : '-');
    n += 6;
#endif

    while (n < term.t_ncol)             /* Pad to full width. */
        {
        vtputc('-');
        ++n;
        }
}

/*
 * Send a command to the terminal to move the hardware cursor to row "row"
 * and column "col". The row and column arguments are origin 0. Optimize out
 * random calls. Update "ttrow" and "ttcol".
 */
movecursor(row, col)
    {
    if (row!=ttrow || col!=ttcol)
        {
        ttrow = row;
        ttcol = col;
        (*term.t_move)(row, col);
        }
    }

/*
 * Erase the message line. This is a special routine because the message line
 * is not considered to be part of the virtual screen. It always works
 * immediately; the terminal buffer is flushed via a call to the flusher.
 */
mlerase()
    {
    movecursor(term.t_nrow, 0);
    (*term.t_eeol)();
    (*term.t_flush)();
    mpresf = FALSE;
    }

/*
 * Ask a yes or no question in the message line. Return either TRUE, FALSE, or
 * ABORT. The ABORT status is returned if the user bumps out of the question
 * with a ^G. Used any time a confirmation is required.
 */
mlyesno(prompt)
    char *prompt;
    {
    register int s;
    char buf[64];

    for (;;)
        {
        strcpy(buf, prompt);
        strcat(buf, " [y/n]? ");
        s = mlreply(buf, buf, sizeof(buf));

        if (s == ABORT)
            return (ABORT);

        if (s != FALSE)
            {
            if (buf[0]=='y' || buf[0]=='Y')
                return (TRUE);

            if (buf[0]=='n' || buf[0]=='N')
                return (FALSE);
            }
        }
    }

/*
 * Write a prompt into the message line, then read back a response. Keep
 * track of the physical position of the cursor. If we are in a keyboard
 * macro throw the prompt away, and return the remembered response. This
 * lets macros run at full speed. The reply is always terminated by a carriage
 * return. Handle erase, kill, and abort keys.
 */
mlreply(prompt, buf, nbuf)
    char *prompt;
    char *buf;
    {
    register int cpos;
    register int i;
    register int c;

    cpos = 0;

    if (kbdmop != NULL)
        {
        while ((c = *kbdmop++) != '\0')
            buf[cpos++] = c;

        buf[cpos] = 0;

        if (buf[0] == 0)
            return (FALSE);

        return (TRUE);
        }

    mlwrite(prompt);

    for (;;)
        {
        c = (*term.t_getchar)();

        switch (c)
            {
            case 0x0D:                  /* Return, end of line */
                buf[cpos++] = 0;

                if (kbdmip != NULL)
                    {
                    if (kbdmip+cpos > &kbdm[NKBDM-3])
                        {
                        ctrlg(FALSE, 0);
                        (*term.t_flush)();
                        return (ABORT);
                        }

                    for (i=0; i<cpos; ++i)
                        *kbdmip++ = buf[i];
                    }

                (*term.t_putchar)('\r');
                ttcol = 0;
                (*term.t_flush)();

                if (buf[0] == 0)
                    return (FALSE);

                return (TRUE);

            case 0x07:                  /* Bell, abort */
                (*term.t_putchar)('^');
                (*term.t_putchar)('G');
                ttcol += 2;
                ctrlg(FALSE, 0);
                (*term.t_flush)();
                return (ABORT);

            case 0x7F:                  /* Rubout, erase */
            case 0x08:                  /* Backspace, erase */
                if (cpos != 0)
                    {
                    (*term.t_putchar)('\b');
                    (*term.t_putchar)(' ');
                    (*term.t_putchar)('\b');
                    --ttcol;

                    if (buf[--cpos] < 0x20)
                        {
                        (*term.t_putchar)('\b');
                        (*term.t_putchar)(' ');
                        (*term.t_putchar)('\b');
                        --ttcol;
                        }

                    (*term.t_flush)();
                    }

                break;

            case 0x15:                  /* C-U, kill */
                while (cpos != 0)
                    {
                    (*term.t_putchar)('\b');
                    (*term.t_putchar)(' ');
                    (*term.t_putchar)('\b');
                    --ttcol;

                    if (buf[--cpos] < 0x20)
                        {
                        (*term.t_putchar)('\b');
                        (*term.t_putchar)(' ');
                        (*term.t_putchar)('\b');
                        --ttcol;
                        }
                    }

                (*term.t_flush)();
                break;

            default:
                if (cpos < nbuf-1)
                    {
                    buf[cpos++] = c;

                    if (c < ' ')
                        {
                        (*term.t_putchar)('^');
                        ++ttcol;
                        c ^= 0x40;
                        }

                    (*term.t_putchar)(c);
                    ++ttcol;
                    (*term.t_flush)();
                    }
            }
        }
    }

/*
 * Write a message into the message line. Keep track of the physical cursor
 * position. A small class of printf like format items is handled. Assumes the
 * stack grows down; this assumption is made by the "++" in the argument scan
 * loop. Set the "message line" flag TRUE.
 */
mlwrite(fmt, arg)
    char *fmt;
    {
    register int c;
    register char *ap;

    movecursor(term.t_nrow, 0);
    ap = (char *) &arg;
    while ((c = *fmt++) != 0) {
        if (c != '%') {
            (*term.t_putchar)(c);
            ++ttcol;
            }
        else
            {
            c = *fmt++;
            switch (c) {
                case 'd':
                    mlputi(*(int *)ap, 10);
                    ap += sizeof(int);
                    break;

                case 'o':
                    mlputi(*(int *)ap,  8);
                    ap += sizeof(int);
                    break;

                case 'x':
                    mlputi(*(int *)ap, 16);
                    ap += sizeof(int);
                    break;

                case 'D':
                    mlputli(*(long *)ap, 10);
                    ap += sizeof(long);
                    break;

                case 's':
                    mlputs(*(char **)ap);
                    ap += sizeof(char *);
                    break;

                default:
                    (*term.t_putchar)(c);
                    ++ttcol;
                }
            }
        }
    (*term.t_eeol)();
    (*term.t_flush)();
    mpresf = TRUE;
    }

/*
 * Write out a string. Update the physical cursor position. This assumes that
 * the characters in the string all have width "1"; if this is not the case
 * things will get screwed up a little.
 */
mlputs(s)
    char *s;
    {
    register int c;

    while ((c = *s++) != 0)
        {
        (*term.t_putchar)(c);
        ++ttcol;
        }
    }

/*
 * Write out an integer, in the specified radix. Update the physical cursor
 * position. This will not handle any negative numbers; maybe it should.
 */
mlputi(i, r)
    {
    register int q;
    static char hexdigits[] = "0123456789ABCDEF";

    if (i < 0)
        {
        i = -i;
        (*term.t_putchar)('-');
        }

    q = i/r;

    if (q != 0)
        mlputi(q, r);

    (*term.t_putchar)(hexdigits[i%r]);
    ++ttcol;
    }

/*
 * do the same except as a long integer.
 */
mlputli(l, r)
    long l;
    {
    register long q;

    if (l < 0)
        {
        l = -l;
        (*term.t_putchar)('-');
        }

    q = l/r;

    if (q != 0)
        mlputli(q, r);

    (*term.t_putchar)((int)(l%r)+'0');
    ++ttcol;
    }

#if RAINBOW

putline(row, col, buf)
    int row, col;
    char buf[];
    {
    int n;

    n = strlen(buf);
    if (col + n - 1 > term.t_ncol)
        n = term.t_ncol - col + 1;
    Put_Data(row, col, n, buf);
    }
#endif

==================================================
file.c
==================================================
/*
 * The routines in this file
 * handle the reading and writing of
 * disk files. All of details about the
 * reading and writing of the disk are
 * in "fileio.c".
 */
#include        <stdio.h>
#include        "ed.h"

/*
 * Read a file into the current
 * buffer. This is really easy; all you do it
 * find the name of the file, and call the standard
 * "read a file into the current buffer" code.
 * Bound to "C-X C-R".
 */
fileread(f, n)
{
        register int    s;
        char            fname[NFILEN];

        if ((s=mlreply("Read file: ", fname, NFILEN)) != TRUE)
                return (s);
        return (readin(fname));
}

/*
 * Select a file for editing.
 * Look around to see if you can find the
 * fine in another buffer; if you can find it
 * just switch to the buffer. If you cannot find
 * the file, create a new buffer, read in the
 * text, and switch to the new buffer.
 * Bound to C-X C-V.
 */
filevisit(f, n)
{
        register BUFFER *bp;
        register WINDOW *wp;
        register LINE   *lp;
        register int    i;
        register int    s;
        char            bname[NBUFN];
        char            fname[NFILEN];

        if ((s=mlreply("Visit file: ", fname, NFILEN)) != TRUE)
                return (s);
        for (bp=bheadp; bp!=NULL; bp=bp->b_bufp) {
                if ((bp->b_flag&BFTEMP)==0 && strcmp(bp->b_fname, fname)==0) {
                        if (--curbp->b_nwnd == 0) {
                                curbp->b_dotp  = curwp->w_dotp;
                                curbp->b_doto  = curwp->w_doto;
                                curbp->b_markp = curwp->w_markp;
                                curbp->b_marko = curwp->w_marko;
                        }
                        curbp = bp;
                        curwp->w_bufp  = bp;
                        if (bp->b_nwnd++ == 0) {
                                curwp->w_dotp  = bp->b_dotp;
                                curwp->w_doto  = bp->b_doto;
                                curwp->w_markp = bp->b_markp;
                                curwp->w_marko = bp->b_marko;
                        } else {
                                wp = wheadp;
                                while (wp != NULL) {
                                        if (wp!=curwp && wp->w_bufp==bp) {
                                                curwp->w_dotp  = wp->w_dotp;
                                                curwp->w_doto  = wp->w_doto;
                                                curwp->w_markp = wp->w_markp;
                                                curwp->w_marko = wp->w_marko;
                                                break;
                                        }
                                        wp = wp->w_wndp;
                                }
                        }
                        lp = curwp->w_dotp;
                        i = curwp->w_ntrows/2;
                        while (i-- && lback(lp)!=curbp->b_linep)
                                lp = lback(lp);
                        curwp->w_linep = lp;
                        curwp->w_flag |= WFMODE|WFHARD;
                        mlwrite("[Old buffer]");
                        return (TRUE);
                }
        }
        makename(bname, fname);                 /* New buffer name.     */
        while ((bp=bfind(bname, FALSE, 0)) != NULL) {
                s = mlreply("Buffer name: ", bname, NBUFN);
                if (s == ABORT)                 /* ^G to just quit      */
                        return (s);
                if (s == FALSE) {               /* CR to clobber it     */
                        makename(bname, fname);
                        break;
                }
        }
        if (bp==NULL && (bp=bfind(bname, TRUE, 0))==NULL) {
                mlwrite("Cannot create buffer");
                return (FALSE);
        }
        if (--curbp->b_nwnd == 0) {             /* Undisplay.           */
                curbp->b_dotp = curwp->w_dotp;
                curbp->b_doto = curwp->w_doto;
                curbp->b_markp = curwp->w_markp;
                curbp->b_marko = curwp->w_marko;
        }
        curbp = bp;                             /* Switch to it.        */
        curwp->w_bufp = bp;
        curbp->b_nwnd++;
        return (readin(fname));                 /* Read it in.          */
}

/*
 * Read file "fname" into the current
 * buffer, blowing away any text found there. Called
 * by both the read and visit commands. Return the final
 * status of the read. Also called by the mainline,
 * to read in a file specified on the command line as
 * an argument.
 */
readin(fname)
char    fname[];
{
        register LINE   *lp1;
        register LINE   *lp2;
        register int    i;
        register WINDOW *wp;
        register BUFFER *bp;
        register int    s;
        register int    nbytes;
        register int    nline;
        char            line[NLINE];

        bp = curbp;                             /* Cheap.               */
        if ((s=bclear(bp)) != TRUE)             /* Might be old.        */
                return (s);
        bp->b_flag &= ~(BFTEMP|BFCHG);
        strcpy(bp->b_fname, fname);
        if ((s=ffropen(fname)) == FIOERR)       /* Hard file open.      */
                goto out;
        if (s == FIOFNF) {                      /* File not found.      */
                mlwrite("[New file]");
                goto out;
        }
        mlwrite("[Reading file]");
        nline = 0;
        while ((s=ffgetline(line, NLINE)) == FIOSUC) {
                nbytes = strlen(line);
                if ((lp1=lalloc(nbytes)) == NULL) {
                        s = FIOERR;             /* Keep message on the  */
                        break;                  /* display.             */
                }
                lp2 = lback(curbp->b_linep);
                lp2->l_fp = lp1;
                lp1->l_fp = curbp->b_linep;
                lp1->l_bp = lp2;
                curbp->b_linep->l_bp = lp1;
                for (i=0; i<nbytes; ++i)
                        lputc(lp1, i, line[i]);
                ++nline;
        }
        ffclose();                              /* Ignore errors.       */
        if (s == FIOEOF) {                      /* Don't zap message!   */
                if (nline == 1)
                        mlwrite("[Read 1 line]");
                else
                        mlwrite("[Read %d lines]", nline);
        }
out:
        for (wp=wheadp; wp!=NULL; wp=wp->w_wndp) {
                if (wp->w_bufp == curbp) {
                        wp->w_linep = lforw(curbp->b_linep);
                        wp->w_dotp  = lforw(curbp->b_linep);
                        wp->w_doto  = 0;
                        wp->w_markp = NULL;
                        wp->w_marko = 0;
                        wp->w_flag |= WFMODE|WFHARD;
                }
        }
        if (s == FIOERR)                        /* False if error.      */
                return (FALSE);
        return (TRUE);
}

/*
 * Take a file name, and from it
 * fabricate a buffer name. This routine knows
 * about the syntax of file names on the target system.
 * I suppose that this information could be put in
 * a better place than a line of code.
 */
makename(bname, fname)
char    bname[];
char    fname[];
{
        register char   *cp1;
        register char   *cp2;

        cp1 = &fname[0];
        while (*cp1 != 0)
                ++cp1;

#if     AMIGA
        while (cp1!=&fname[0] && cp1[-1]!=':' && cp1[-1]!='/')
                --cp1;
#endif
#if     VMS
        while (cp1!=&fname[0] && cp1[-1]!=':' && cp1[-1]!=']')
                --cp1;
#endif
#if     CPM
        while (cp1!=&fname[0] && cp1[-1]!=':')
                --cp1;
#endif
#if     MSDOS
        while (cp1!=&fname[0] && cp1[-1]!=':' && cp1[-1]!='\\')
                --cp1;
#endif
#if     V7
        while (cp1!=&fname[0] && cp1[-1]!='/')
                --cp1;
#endif
        cp2 = &bname[0];
        while (cp2!=&bname[NBUFN-1] && *cp1!=0 && *cp1!=';')
                *cp2++ = *cp1++;
        *cp2 = 0;
}

/*
 * Ask for a file name, and write the
 * contents of the current buffer to that file.
 * Update the remembered file name and clear the
 * buffer changed flag. This handling of file names
 * is different from the earlier versions, and
 * is more compatable with Gosling EMACS than
 * with ITS EMACS. Bound to "C-X C-W".
 */
filewrite(f, n)
{
        register WINDOW *wp;
        register int    s;
        char            fname[NFILEN];

        if ((s=mlreply("Write file: ", fname, NFILEN)) != TRUE)
                return (s);
        if ((s=writeout(fname)) == TRUE) {
                strcpy(curbp->b_fname, fname);
                curbp->b_flag &= ~BFCHG;
                wp = wheadp;                    /* Update mode lines.   */
                while (wp != NULL) {
                        if (wp->w_bufp == curbp)
                                wp->w_flag |= WFMODE;
                        wp = wp->w_wndp;
                }
        }
        return (s);
}

/*
 * Save the contents of the current
 * buffer in its associatd file. No nothing
 * if nothing has changed (this may be a bug, not a
 * feature). Error if there is no remembered file
 * name for the buffer. Bound to "C-X C-S". May
 * get called by "C-Z".
 */
filesave(f, n)
{
        register WINDOW *wp;
        register int    s;

        if ((curbp->b_flag&BFCHG) == 0)         /* Return, no changes.  */
                return (TRUE);
        if (curbp->b_fname[0] == 0) {           /* Must have a name.    */
                mlwrite("No file name");
                return (FALSE);
        }
        if ((s=writeout(curbp->b_fname)) == TRUE) {
                curbp->b_flag &= ~BFCHG;
                wp = wheadp;                    /* Update mode lines.   */
                while (wp != NULL) {
                        if (wp->w_bufp == curbp)
                                wp->w_flag |= WFMODE;
                        wp = wp->w_wndp;
                }
        }
        return (s);
}

/*
 * This function performs the details of file
 * writing. Uses the file management routines in the
 * "fileio.c" package. The number of lines written is
 * displayed. Sadly, it looks inside a LINE; provide
 * a macro for this. Most of the grief is error
 * checking of some sort.
 */
writeout(fn)
char    *fn;
{
        register int    s;
        register LINE   *lp;
        register int    nline;

        if ((s=ffwopen(fn)) != FIOSUC)          /* Open writes message. */
                return (FALSE);
        lp = lforw(curbp->b_linep);             /* First line.          */
        nline = 0;                              /* Number of lines.     */
        while (lp != curbp->b_linep) {
                if ((s=ffputline(&lp->l_text[0], llength(lp))) != FIOSUC)
                        break;
                ++nline;
                lp = lforw(lp);
        }
        if (s == FIOSUC) {                      /* No write error.      */
                s = ffclose();
                if (s == FIOSUC) {              /* No close error.      */
                        if (nline == 1)
                                mlwrite("[Wrote 1 line]");
                        else
                                mlwrite("[Wrote %d lines]", nline);
                }
        } else                                  /* Ignore close error   */
                ffclose();                      /* if a write error.    */
        if (s != FIOSUC)                        /* Some sort of error.  */
                return (FALSE);
        return (TRUE);
}

/*
 * The command allows the user
 * to modify the file name associated with
 * the current buffer. It is like the "f" command
 * in UNIX "ed". The operation is simple; just zap
 * the name in the BUFFER structure, and mark the windows
 * as needing an update. You can type a blank line at the
 * prompt if you wish.
 */
filename(f, n)
{
        register WINDOW *wp;
        register int    s;
        char            fname[NFILEN];

        if ((s=mlreply("Name: ", fname, NFILEN)) == ABORT)
                return (s);
        if (s == FALSE)
                strcpy(curbp->b_fname, "");
        else
                strcpy(curbp->b_fname, fname);
        wp = wheadp;                            /* Update mode lines.   */
        while (wp != NULL) {
                if (wp->w_bufp == curbp)
                        wp->w_flag |= WFMODE;
                wp = wp->w_wndp;
        }
        return (TRUE);
}

==================================================
fileio.c
==================================================

/*
 * The routines in this file read and write ASCII files from the disk. All of
 * the knowledge about files are here. A better message writing scheme should
 * be used.
 */
#include        <stdio.h>
#include        "ed.h"

FILE    *ffp;                           /* File pointer, all functions. */

/*
 * Open a file for reading.
 */
ffropen(fn)
char    *fn;
{
        if ((ffp=fopen(fn, "r")) == NULL)
                return (FIOFNF);
        return (FIOSUC);
}

/*
 * Open a file for writing. Return TRUE if all is well, and FALSE on error
 * (cannot create).
 */
ffwopen(fn)
char    *fn;
{
#if     VMS
        register int    fd;

        if ((fd=creat(fn, 0666, "rfm=var", "rat=cr")) < 0
        || (ffp=fdopen(fd, "w")) == NULL) {
#else
        if ((ffp=fopen(fn, "w")) == NULL) {
#endif
                mlwrite("Cannot open file for writing");
                return (FIOERR);
        }
        return (FIOSUC);
}

/*
 * Close a file. Should look at the status in all systems.
 */
ffclose()
{
#if     V7
        if (fclose(ffp) != FALSE) {
                mlwrite("Error closing file");
                return(FIOERR);
        }
        return(FIOSUC);
#endif
        fclose(ffp);
        return (FIOSUC);
}

/*
 * Write a line to the already opened file. The "buf" points to the buffer,
 * and the "nbuf" is its length, less the free newline. Return the status.
 * Check only at the newline.
 */
ffputline(buf, nbuf)
char    buf[];
{
        register int    i;

        for (i = 0; i < nbuf; ++i)
                fputc(buf[i]&0xFF, ffp);

        fputc('\n', ffp);

        if (ferror(ffp)) {
                mlwrite("Write I/O error");
                return (FIOERR);
        }

        return (FIOSUC);
}

/*
 * Read a line from a file, and store the bytes in the supplied buffer. The
 * "nbuf" is the length of the buffer. Complain about long lines and lines
 * at the end of the file that don't have a newline present. Check for I/O
 * errors too. Return status.
 */
ffgetline(buf, nbuf)
register char   buf[];
{
        register int    c;
        register int    i;

        i = 0;

        while ((c = fgetc(ffp)) != EOF && c != '\n') {
                if (i >= nbuf-1) {
                        mlwrite("File has long line");
                        return (FIOERR);
                }
                buf[i++] = c;
        }

        if (c == EOF) {
                if (ferror(ffp)) {
                        mlwrite("File read error");
                        return (FIOERR);
                }

                if (i != 0) {
                        mlwrite("File has funny line at EOF");
                        return (FIOERR);
                }
                return (FIOEOF);
        }

        buf[i] = 0;
        return (FIOSUC);
}

==================================================
line.c
==================================================
/*
 * The functions in this file are a general set of line management utilities.
 * They are the only routines that touch the text. They also touch the buffer
 * and window structures, to make sure that the necessary updating gets done.
 * There are routines in this file that handle the kill buffer too. It isn't
 * here for any good reason.
 *
 * Note that this code only updates the dot and mark values in the window list.
 * Since all the code acts on the current window, the buffer that we are
 * editing must be being displayed, which means that "b_nwnd" is non zero,
 * which means that the dot and mark values in the buffer headers are nonsense.
 */

#include        <stdio.h>
#include        "ed.h"

#define NBLOCK  16                      /* Line block chunk size        */
#define KBLOCK  256                     /* Kill buffer block size       */

char    *kbufp  = NULL;                 /* Kill buffer data             */
int     kused   = 0;                    /* # of bytes used in KB        */
int     ksize   = 0;                    /* # of bytes allocated in KB   */

/*
 * This routine allocates a block of memory large enough to hold a LINE
 * containing "used" characters. The block is always rounded up a bit. Return
 * a pointer to the new block, or NULL if there isn't any memory left. Print a
 * message in the message line if no space.
 */
LINE    *
lalloc(used)
register int    used;
{
        register LINE   *lp;
        register int    size;

        size = (used+NBLOCK-1) & ~(NBLOCK-1);
        if (size == 0)                          /* Assume that an empty */
                size = NBLOCK;                  /* line is for type-in. */
        if ((lp = (LINE *) malloc(sizeof(LINE)+size)) == NULL) {
                mlwrite("Cannot allocate %d bytes", size);
                return (NULL);
        }
        lp->l_size = size;
        lp->l_used = used;
        return (lp);
}

/*
 * Delete line "lp". Fix all of the links that might point at it (they are
 * moved to offset 0 of the next line. Unlink the line from whatever buffer it
 * might be in. Release the memory. The buffers are updated too; the magic
 * conditions described in the above comments don't hold here.
 */
lfree(lp)
register LINE   *lp;
{
        register BUFFER *bp;
        register WINDOW *wp;

        wp = wheadp;
        while (wp != NULL) {
                if (wp->w_linep == lp)
                        wp->w_linep = lp->l_fp;
                if (wp->w_dotp  == lp) {
                        wp->w_dotp  = lp->l_fp;
                        wp->w_doto  = 0;
                }
                if (wp->w_markp == lp) {
                        wp->w_markp = lp->l_fp;
                        wp->w_marko = 0;
                }
                wp = wp->w_wndp;
        }
        bp = bheadp;
        while (bp != NULL) {
                if (bp->b_nwnd == 0) {
                        if (bp->b_dotp  == lp) {
                                bp->b_dotp = lp->l_fp;
                                bp->b_doto = 0;
                        }
                        if (bp->b_markp == lp) {
                                bp->b_markp = lp->l_fp;
                                bp->b_marko = 0;
                        }
                }
                bp = bp->b_bufp;
        }
        lp->l_bp->l_fp = lp->l_fp;
        lp->l_fp->l_bp = lp->l_bp;
        free((char *) lp);
}

/*
 * This routine gets called when a character is changed in place in the current
 * buffer. It updates all of the required flags in the buffer and window
 * system. The flag used is passed as an argument; if the buffer is being
 * displayed in more than 1 window we change EDIT t HARD. Set MODE if the
 * mode line needs to be updated (the "*" has to be set).
 */
lchange(flag)
register int    flag;
{
        register WINDOW *wp;

        if (curbp->b_nwnd != 1)                 /* Ensure hard.         */
                flag = WFHARD;
        if ((curbp->b_flag&BFCHG) == 0) {       /* First change, so     */
                flag |= WFMODE;                 /* update mode lines.   */
                curbp->b_flag |= BFCHG;
        }
        wp = wheadp;
        while (wp != NULL) {
                if (wp->w_bufp == curbp)
                        wp->w_flag |= flag;
                wp = wp->w_wndp;
        }
}

/*
 * Insert "n" copies of the character "c" at the current location of dot. In
 * the easy case all that happens is the text is stored in the line. In the
 * hard case, the line has to be reallocated. When the window list is updated,
 * take special care; I screwed it up once. You always update dot in the
 * current window. You update mark, and a dot in another window, if it is
 * greater than the place where you did the insert. Return TRUE if all is
 * well, and FALSE on errors.
 */
linsert(n, c)
{
        register char   *cp1;
        register char   *cp2;
        register LINE   *lp1;
        register LINE   *lp2;
        register LINE   *lp3;
        register int    doto;
        register int    i;
        register WINDOW *wp;

        lchange(WFEDIT);
        lp1 = curwp->w_dotp;                    /* Current line         */
        if (lp1 == curbp->b_linep) {            /* At the end: special  */
                if (curwp->w_doto != 0) {
                        mlwrite("bug: linsert");
                        return (FALSE);
                }
                if ((lp2=lalloc(n)) == NULL)    /* Allocate new line    */
                        return (FALSE);
                lp3 = lp1->l_bp;                /* Previous line        */
                lp3->l_fp = lp2;                /* Link in              */
                lp2->l_fp = lp1;
                lp1->l_bp = lp2;
                lp2->l_bp = lp3;
                for (i=0; i<n; ++i)
                        lp2->l_text[i] = c;
                curwp->w_dotp = lp2;
                curwp->w_doto = n;
                return (TRUE);
        }
        doto = curwp->w_doto;                   /* Save for later.      */
        if (lp1->l_used+n > lp1->l_size) {      /* Hard: reallocate     */
                if ((lp2=lalloc(lp1->l_used+n)) == NULL)
                        return (FALSE);
                cp1 = &lp1->l_text[0];
                cp2 = &lp2->l_text[0];
                while (cp1 != &lp1->l_text[doto])
                        *cp2++ = *cp1++;
                cp2 += n;
                while (cp1 != &lp1->l_text[lp1->l_used])
                        *cp2++ = *cp1++;
                lp1->l_bp->l_fp = lp2;
                lp2->l_fp = lp1->l_fp;
                lp1->l_fp->l_bp = lp2;
                lp2->l_bp = lp1->l_bp;
                free((char *) lp1);
        } else {                                /* Easy: in place       */
                lp2 = lp1;                      /* Pretend new line     */
                lp2->l_used += n;
                cp2 = &lp1->l_text[lp1->l_used];
                cp1 = cp2-n;
                while (cp1 != &lp1->l_text[doto])
                        *--cp2 = *--cp1;
        }
        for (i=0; i<n; ++i)                     /* Add the characters   */
                lp2->l_text[doto+i] = c;
        wp = wheadp;                            /* Update windows       */
        while (wp != NULL) {
                if (wp->w_linep == lp1)
                        wp->w_linep = lp2;
                if (wp->w_dotp == lp1) {
                        wp->w_dotp = lp2;
                        if (wp==curwp || wp->w_doto>doto)
                                wp->w_doto += n;
                }
                if (wp->w_markp == lp1) {
                        wp->w_markp = lp2;
                        if (wp->w_marko > doto)
                                wp->w_marko += n;
                }
                wp = wp->w_wndp;
        }
        return (TRUE);
}

/*
 * Insert a newline into the buffer at the current location of dot in the
 * current window. The funny ass-backwards way it does things is not a botch;
 * it just makes the last line in the file not a special case. Return TRUE if
 * everything works out and FALSE on error (memory allocation failure). The
 * update of dot and mark is a bit easier then in the above case, because the
 * split forces more updating.
 */
lnewline()
{
        register char   *cp1;
        register char   *cp2;
        register LINE   *lp1;
        register LINE   *lp2;
        register int    doto;
        register WINDOW *wp;

        lchange(WFHARD);
        lp1  = curwp->w_dotp;                   /* Get the address and  */
        doto = curwp->w_doto;                   /* offset of "."        */
        if ((lp2=lalloc(doto)) == NULL)         /* New first half line  */
                return (FALSE);
        cp1 = &lp1->l_text[0];                  /* Shuffle text around  */
        cp2 = &lp2->l_text[0];
        while (cp1 != &lp1->l_text[doto])
                *cp2++ = *cp1++;
        cp2 = &lp1->l_text[0];
        while (cp1 != &lp1->l_text[lp1->l_used])
                *cp2++ = *cp1++;
        lp1->l_used -= doto;
        lp2->l_bp = lp1->l_bp;
        lp1->l_bp = lp2;
        lp2->l_bp->l_fp = lp2;
        lp2->l_fp = lp1;
        wp = wheadp;                            /* Windows              */
        while (wp != NULL) {
                if (wp->w_linep == lp1)
                        wp->w_linep = lp2;
                if (wp->w_dotp == lp1) {
                        if (wp->w_doto < doto)
                                wp->w_dotp = lp2;
                        else
                                wp->w_doto -= doto;
                }
                if (wp->w_markp == lp1) {
                        if (wp->w_marko < doto)
                                wp->w_markp = lp2;
                        else
                                wp->w_marko -= doto;
                }
                wp = wp->w_wndp;
        }       
        return (TRUE);
}

/*
 * This function deletes "n" bytes, starting at dot. It understands how do deal
 * with end of lines, etc. It returns TRUE if all of the characters were
 * deleted, and FALSE if they were not (because dot ran into the end of the
 * buffer. The "kflag" is TRUE if the text should be put in the kill buffer.
 */
ldelete(n, kflag)
{
        register char   *cp1;
        register char   *cp2;
        register LINE   *dotp;
        register int    doto;
        register int    chunk;
        register WINDOW *wp;

        while (n != 0) {
                dotp = curwp->w_dotp;
                doto = curwp->w_doto;
                if (dotp == curbp->b_linep)     /* Hit end of buffer.   */
                        return (FALSE);
                chunk = dotp->l_used-doto;      /* Size of chunk.       */
                if (chunk > n)
                        chunk = n;
                if (chunk == 0) {               /* End of line, merge.  */
                        lchange(WFHARD);
                        if (ldelnewline() == FALSE
                        || (kflag!=FALSE && kinsert('\n')==FALSE))
                                return (FALSE);
                        --n;
                        continue;
                }
                lchange(WFEDIT);
                cp1 = &dotp->l_text[doto];      /* Scrunch text.        */
                cp2 = cp1 + chunk;
                if (kflag != FALSE) {           /* Kill?                */
                        while (cp1 != cp2) {
                                if (kinsert(*cp1) == FALSE)
                                        return (FALSE);
                                ++cp1;
                        }
                        cp1 = &dotp->l_text[doto];
                }
                while (cp2 != &dotp->l_text[dotp->l_used])
                        *cp1++ = *cp2++;
                dotp->l_used -= chunk;
                wp = wheadp;                    /* Fix windows          */
                while (wp != NULL) {
                        if (wp->w_dotp==dotp && wp->w_doto>=doto) {
                                wp->w_doto -= chunk;
                                if (wp->w_doto < doto)
                                        wp->w_doto = doto;
                        }       
                        if (wp->w_markp==dotp && wp->w_marko>=doto) {
                                wp->w_marko -= chunk;
                                if (wp->w_marko < doto)
                                        wp->w_marko = doto;
                        }
                        wp = wp->w_wndp;
                }
                n -= chunk;
        }
        return (TRUE);
}

/*
 * Delete a newline. Join the current line with the next line. If the next line
 * is the magic header line always return TRUE; merging the last line with the
 * header line can be thought of as always being a successful operation, even
 * if nothing is done, and this makes the kill buffer work "right". Easy cases
 * can be done by shuffling data around. Hard cases require that lines be moved
 * about in memory. Return FALSE on error and TRUE if all looks ok. Called by
 * "ldelete" only.
 */
ldelnewline()
{
        register char   *cp1;
        register char   *cp2;
        register LINE   *lp1;
        register LINE   *lp2;
        register LINE   *lp3;
        register WINDOW *wp;

        lp1 = curwp->w_dotp;
        lp2 = lp1->l_fp;
        if (lp2 == curbp->b_linep) {            /* At the buffer end.   */
                if (lp1->l_used == 0)           /* Blank line.          */
                        lfree(lp1);
                return (TRUE);
        }
        if (lp2->l_used <= lp1->l_size-lp1->l_used) {
                cp1 = &lp1->l_text[lp1->l_used];
                cp2 = &lp2->l_text[0];
                while (cp2 != &lp2->l_text[lp2->l_used])
                        *cp1++ = *cp2++;
                wp = wheadp;
                while (wp != NULL) {
                        if (wp->w_linep == lp2)
                                wp->w_linep = lp1;
                        if (wp->w_dotp == lp2) {
                                wp->w_dotp  = lp1;
                                wp->w_doto += lp1->l_used;
                        }
                        if (wp->w_markp == lp2) {
                                wp->w_markp  = lp1;
                                wp->w_marko += lp1->l_used;
                        }
                        wp = wp->w_wndp;
                }               
                lp1->l_used += lp2->l_used;
                lp1->l_fp = lp2->l_fp;
                lp2->l_fp->l_bp = lp1;
                free((char *) lp2);
                return (TRUE);
        }
        if ((lp3=lalloc(lp1->l_used+lp2->l_used)) == NULL)
                return (FALSE);
        cp1 = &lp1->l_text[0];
        cp2 = &lp3->l_text[0];
        while (cp1 != &lp1->l_text[lp1->l_used])
                *cp2++ = *cp1++;
        cp1 = &lp2->l_text[0];
        while (cp1 != &lp2->l_text[lp2->l_used])
                *cp2++ = *cp1++;
        lp1->l_bp->l_fp = lp3;
        lp3->l_fp = lp2->l_fp;
        lp2->l_fp->l_bp = lp3;
        lp3->l_bp = lp1->l_bp;
        wp = wheadp;
        while (wp != NULL) {
                if (wp->w_linep==lp1 || wp->w_linep==lp2)
                        wp->w_linep = lp3;
                if (wp->w_dotp == lp1)
                        wp->w_dotp  = lp3;
                else if (wp->w_dotp == lp2) {
                        wp->w_dotp  = lp3;
                        wp->w_doto += lp1->l_used;
                }
                if (wp->w_markp == lp1)
                        wp->w_markp  = lp3;
                else if (wp->w_markp == lp2) {
                        wp->w_markp  = lp3;
                        wp->w_marko += lp1->l_used;
                }
                wp = wp->w_wndp;
        }
        free((char *) lp1);
        free((char *) lp2);
        return (TRUE);
}

/*
 * Delete all of the text saved in the kill buffer. Called by commands when a
 * new kill context is being created. The kill buffer array is released, just
 * in case the buffer has grown to immense size. No errors.
 */
kdelete()
{
        if (kbufp != NULL) {
                free((char *) kbufp);
                kbufp = NULL;
                kused = 0;
                ksize = 0;
        }
}

/*
 * Insert a character to the kill buffer, enlarging the buffer if there isn't
 * any room. Always grow the buffer in chunks, on the assumption that if you
 * put something in the kill buffer you are going to put more stuff there too
 * later. Return TRUE if all is well, and FALSE on errors.
 */
kinsert(c)
{
        register char   *nbufp;
        register int    i;

        if (kused == ksize) {
                if ((nbufp=malloc(ksize+KBLOCK)) == NULL)
                        return (FALSE);
                for (i=0; i<ksize; ++i)
                        nbufp[i] = kbufp[i];
                if (kbufp != NULL)
                        free((char *) kbufp);
                kbufp  = nbufp;
                ksize += KBLOCK;
        }
        kbufp[kused++] = c;
        return (TRUE);
}

/*
 * This function gets characters from the kill buffer. If the character index
 * "n" is off the end, it returns "-1". This lets the caller just scan along
 * until it gets a "-1" back.
 */
kremove(n)
{
        if (n >= kused)
                return (-1);
        else
                return (kbufp[n] & 0xFF);
}


==================================================
main.c
==================================================
/*
 * This program is in public domain; written by Dave G. Conroy.
 * This file contains the main driving routine, and some keyboard processing
 * code, for the MicroEMACS screen editor.
 *
 * REVISION HISTORY:
 *
 * 1.0  Steve Wilhite, 30-Nov-85
 *      - Removed the old LK201 and VT100 logic. Added code to support the
 *        DEC Rainbow keyboard (which is a LK201 layout) using the the Level
 *        1 Console In ROM INT. See "rainbow.h" for the function key definitions.
 *
 * 2.0  George Jones, 12-Dec-85
 *      - Ported to Amiga.
 */
#include        <stdio.h>
#include        "ed.h"

#if     VMS
#include        <ssdef.h>
#define GOOD    (SS$_NORMAL)
#endif

#ifndef GOOD
#define GOOD    0
#endif

int     currow;                         /* Working cursor row           */
int     curcol;                         /* Working cursor column        */
int     fillcol;                        /* Current fill column          */
int     thisflag;                       /* Flags, this command          */
int     lastflag;                       /* Flags, last command          */
int     curgoal;                        /* Goal column                  */
BUFFER  *curbp;                         /* Current buffer               */
WINDOW  *curwp;                         /* Current window               */
BUFFER  *bheadp;                        /* BUFFER listhead              */
WINDOW  *wheadp;                        /* WINDOW listhead              */
BUFFER  *blistp;                        /* Buffer list BUFFER           */
short   kbdm[NKBDM] = {CTLX|')'};       /* Macro                        */
short   *kbdmip;                        /* Input  for above             */
short   *kbdmop;                        /* Output for above             */
char    pat[NPAT];                      /* Pattern                      */

typedef struct  {
        short   k_code;                 /* Key code                     */
        int     (*k_fp)();              /* Routine to handle it         */
}       KEYTAB;

extern  int     ctrlg();                /* Abort out of things          */
extern  int     quit();                 /* Quit                         */
extern  int     ctlxlp();               /* Begin macro                  */
extern  int     ctlxrp();               /* End macro                    */
extern  int     ctlxe();                /* Execute macro                */
extern  int     fileread();             /* Get a file, read only        */
extern  int     filevisit();            /* Get a file, read write       */
extern  int     filewrite();            /* Write a file                 */
extern  int     filesave();             /* Save current file            */
extern  int     filename();             /* Adjust file name             */
extern  int     getccol();              /* Get current column           */
extern  int     gotobol();              /* Move to start of line        */
extern  int     forwchar();             /* Move forward by characters   */
extern  int     gotoeol();              /* Move to end of line          */
extern  int     backchar();             /* Move backward by characters  */
extern  int     forwline();             /* Move forward by lines        */
extern  int     backline();             /* Move backward by lines       */
extern  int     forwpage();             /* Move forward by pages        */
extern  int     backpage();             /* Move backward by pages       */
extern  int     gotobob();              /* Move to start of buffer      */
extern  int     gotoeob();              /* Move to end of buffer        */
extern  int     setfillcol();           /* Set fill column.             */
extern  int     setmark();              /* Set mark                     */
extern  int     swapmark();             /* Swap "." and mark            */
extern  int     forwsearch();           /* Search forward               */
extern  int     backsearch();           /* Search backwards             */
extern  int     showcpos();             /* Show the cursor position     */
extern  int     nextwind();             /* Move to the next window      */
extern  int     prevwind();             /* Move to the previous window  */
extern  int     onlywind();             /* Make current window only one */
extern  int     splitwind();            /* Split current window         */
extern  int     mvdnwind();             /* Move window down             */
extern  int     mvupwind();             /* Move window up               */
extern  int     enlargewind();          /* Enlarge display window.      */
extern  int     shrinkwind();           /* Shrink window.               */
extern  int     listbuffers();          /* Display list of buffers      */
extern  int     usebuffer();            /* Switch a window to a buffer  */
extern  int     killbuffer();           /* Make a buffer go away.       */
extern  int     reposition();           /* Reposition window            */
extern  int     refresh();              /* Refresh the screen           */
extern  int     twiddle();              /* Twiddle characters           */
extern  int     tab();                  /* Insert tab                   */
extern  int     newline();              /* Insert CR-LF                 */
extern  int     indent();               /* Insert CR-LF, then indent    */
extern  int     openline();             /* Open up a blank line         */
extern  int     deblank();              /* Delete blank lines           */
extern  int     quote();                /* Insert literal               */
extern  int     backword();             /* Backup by words              */
extern  int     forwword();             /* Advance by words             */
extern  int     forwdel();              /* Forward delete               */
extern  int     backdel();              /* Backward delete              */
extern  int     kill();                 /* Kill forward                 */
extern  int     yank();                 /* Yank back from killbuffer.   */
extern  int     upperword();            /* Upper case word.             */
extern  int     lowerword();            /* Lower case word.             */
extern  int     upperregion();          /* Upper case region.           */
extern  int     lowerregion();          /* Lower case region.           */
extern  int     capword();              /* Initial capitalize word.     */
extern  int     delfword();             /* Delete forward word.         */
extern  int     delbword();             /* Delete backward word.        */
extern  int     killregion();           /* Kill region.                 */
extern  int     copyregion();           /* Copy region to kill buffer.  */
extern  int     spawncli();             /* Run CLI in a subjob.         */
extern  int     spawn();                /* Run a command in a subjob.   */
extern  int     quickexit();            /* low keystroke style exit.    */

/*
 * Command table.
 * This table  is *roughly* in ASCII order, left to right across the
 * characters of the command. This expains the funny location of the
 * control-X commands.
 */
KEYTAB  keytab[] = {
        CTRL|'@',               &setmark,
        CTRL|'A',               &gotobol,
        CTRL|'B',               &backchar,
        CTRL|'C',               &spawncli,      /* Run CLI in subjob.   */
        CTRL|'D',               &forwdel,
        CTRL|'E',               &gotoeol,
        CTRL|'F',               &forwchar,
        CTRL|'G',               &ctrlg,
        CTRL|'H',               &backdel,
        CTRL|'I',               &tab,
        CTRL|'J',               &indent,
        CTRL|'K',               &kill,
        CTRL|'L',               &refresh,
        CTRL|'M',               &newline,
        CTRL|'N',               &forwline,
        CTRL|'O',               &openline,
        CTRL|'P',               &backline,
        CTRL|'Q',               &quote,         /* Often unreachable    */
        CTRL|'R',               &backsearch,
        CTRL|'S',               &forwsearch,    /* Often unreachable    */
        CTRL|'T',               &twiddle,
        CTRL|'V',               &forwpage,
        CTRL|'W',               &killregion,
        CTRL|'Y',               &yank,
        CTRL|'Z',               &quickexit,     /* quick save and exit  */
        CTLX|CTRL|'B',          &listbuffers,
        CTLX|CTRL|'C',          &quit,          /* Hard quit.           */
        CTLX|CTRL|'F',          &filename,
        CTLX|CTRL|'L',          &lowerregion,
        CTLX|CTRL|'O',          &deblank,
        CTLX|CTRL|'N',          &mvdnwind,
        CTLX|CTRL|'P',          &mvupwind,
        CTLX|CTRL|'R',          &fileread,
        CTLX|CTRL|'S',          &filesave,      /* Often unreachable    */
        CTLX|CTRL|'U',          &upperregion,
        CTLX|CTRL|'V',          &filevisit,
        CTLX|CTRL|'W',          &filewrite,
        CTLX|CTRL|'X',          &swapmark,
        CTLX|CTRL|'Z',          &shrinkwind,
        CTLX|'!',               &spawn,         /* Run 1 command.       */
        CTLX|'=',               &showcpos,
        CTLX|'(',               &ctlxlp,
        CTLX|')',               &ctlxrp,
        CTLX|'1',               &onlywind,
        CTLX|'2',               &splitwind,
        CTLX|'B',               &usebuffer,
        CTLX|'E',               &ctlxe,
        CTLX|'F',               &setfillcol,
        CTLX|'K',               &killbuffer,
        CTLX|'N',               &nextwind,
        CTLX|'P',               &prevwind,
        CTLX|'Z',               &enlargewind,
        META|CTRL|'H',          &delbword,
        META|'!',               &reposition,
        META|'.',               &setmark,
        META|'>',               &gotoeob,
        META|'<',               &gotobob,
        META|'B',               &backword,
        META|'C',               &capword,
        META|'D',               &delfword,
        META|'F',               &forwword,
        META|'L',               &lowerword,
        META|'U',               &upperword,
        META|'V',               &backpage,
        META|'W',               &copyregion,
        META|0x7F,              &delbword,
        0x7F,                   &backdel
};

#define NKEYTAB (sizeof(keytab)/sizeof(keytab[0]))








#if RAINBOW

#include "rainbow.h"

/*
 * Mapping table from the LK201 function keys to the internal EMACS character.
 */

short lk_map[][2] = {
        Up_Key,                         CTRL+'P',
        Down_Key,                       CTRL+'N',
        Left_Key,                       CTRL+'B',
        Right_Key,                      CTRL+'F',
        Shift+Left_Key,                 META+'B',
        Shift+Right_Key,                META+'F',
        Control+Left_Key,               CTRL+'A',
        Control+Right_Key,              CTRL+'E',
        Prev_Scr_Key,                   META+'V',
        Next_Scr_Key,                   CTRL+'V',
        Shift+Up_Key,                   META+'<',
        Shift+Down_Key,                 META+'>',
        Cancel_Key,                     CTRL+'G',
        Find_Key,                       CTRL+'S',
        Shift+Find_Key,                 CTRL+'R',
        Insert_Key,                     CTRL+'Y',
        Options_Key,                    CTRL+'D',
        Shift+Options_Key,              META+'D',
        Remove_Key,                     CTRL+'W',
        Shift+Remove_Key,               META+'W',
        Select_Key,                     CTRL+'@',
        Shift+Select_Key,               CTLX+CTRL+'X',
        Interrupt_Key,                  CTRL+'U',
        Keypad_PF2,                     META+'L',
        Keypad_PF3,                     META+'C',
        Keypad_PF4,                     META+'U',
        Shift+Keypad_PF2,               CTLX+CTRL+'L',
        Shift+Keypad_PF4,               CTLX+CTRL+'U',
        Keypad_1,                       CTLX+'1',
        Keypad_2,                       CTLX+'2',
        Do_Key,                         CTLX+'E',
        Keypad_4,                       CTLX+CTRL+'B',
        Keypad_5,                       CTLX+'B',
        Keypad_6,                       CTLX+'K',
        Resume_Key,                     META+'!',
        Control+Next_Scr_Key,           CTLX+'N',
        Control+Prev_Scr_Key,           CTLX+'P',
        Control+Up_Key,                 CTLX+CTRL+'P',
        Control+Down_Key,               CTLX+CTRL+'N',
        Help_Key,                       CTLX+'=',
        Shift+Do_Key,                   CTLX+'(',
        Control+Do_Key,                 CTLX+')',
        Keypad_0,                       CTLX+'Z',
        Shift+Keypad_0,                 CTLX+CTRL+'Z',
        Main_Scr_Key,                   CTRL+'C',
        Keypad_Enter,                   CTLX+'!',
        Exit_Key,                       CTLX+CTRL+'C',
        Shift+Exit_Key,                 CTRL+'Z'
        };

#define lk_map_size     (sizeof(lk_map)/2)

#endif








main(argc, argv)
char    *argv[];
{
        register int    c;
        register int    f;
        register int    n;
        register int    mflag;
        char            bname[NBUFN];

        strcpy(bname, "main");                  /* Work out the name of */
        if (argc > 1)                           /* the default buffer.  */
                makename(bname, argv[1]);
        edinit(bname);                          /* Buffers, windows.    */
        vtinit();                               /* Displays.            */
        if (argc > 1) {
                update();                       /* You have to update   */
                readin(argv[1]);                /* in case "[New file]" */
        }
        lastflag = 0;                           /* Fake last flags.     */
loop:
        update();                               /* Fix up the screen    */
        c = getkey();
        if (mpresf != FALSE) {
                mlerase();
                update();
                if (c == ' ')                   /* ITS EMACS does this  */
                        goto loop;
        }
        f = FALSE;
        n = 1;
        if (c == (CTRL|'U')) {                  /* ^U, start argument   */
                f = TRUE;
                n = 4;                          /* with argument of 4 */
                mflag = 0;                      /* that can be discarded. */
                mlwrite("Arg: 4");
                while ((c=getkey()) >='0' && c<='9' || c==(CTRL|'U') || c=='-'){
                        if (c == (CTRL|'U'))
                                n = n*4;
                        /*
                         * If dash, and start of argument string, set arg.
                         * to -1.  Otherwise, insert it.
                         */
                        else if (c == '-') {
                                if (mflag)
                                        break;
                                n = 0;
                                mflag = -1;
                        }
                        /*
                         * If first digit entered, replace previous argument
                         * with digit and set sign.  Otherwise, append to arg.
                         */
                        else {
                                if (!mflag) {
                                        n = 0;
                                        mflag = 1;
                                }
                                n = 10*n + c - '0';
                        }
                        mlwrite("Arg: %d", (mflag >=0) ? n : (n ? -n : -1));
                }
                /*
                 * Make arguments preceded by a minus sign negative and change
                 * the special argument "^U -" to an effective "^U -1".
                 */
                if (mflag == -1) {
                        if (n == 0)
                                n++;
                        n = -n;
                }
        }
        if (c == (CTRL|'X'))                    /* ^X is a prefix       */
                c = CTLX | getctl();
        if (kbdmip != NULL) {                   /* Save macro strokes.  */
                if (c!=(CTLX|')') && kbdmip>&kbdm[NKBDM-6]) {
                        ctrlg(FALSE, 0);
                        goto loop;
                }
                if (f != FALSE) {
                        *kbdmip++ = (CTRL|'U');
                        *kbdmip++ = n;
                }
                *kbdmip++ = c;
        }
        execute(c, f, n);                       /* Do it.               */
        goto loop;
}

/*
 * Initialize all of the buffers and windows. The buffer name is passed down
 * as an argument, because the main routine may have been told to read in a
 * file by default, and we want the buffer name to be right.
 */
edinit(bname)
char    bname[];
{
        register BUFFER *bp;
        register WINDOW *wp;

        bp = bfind(bname, TRUE, 0);             /* First buffer         */
        blistp = bfind("[List]", TRUE, BFTEMP); /* Buffer list buffer   */
        wp = (WINDOW *) malloc(sizeof(WINDOW)); /* First window         */
        if (bp==NULL || wp==NULL || blistp==NULL)
                exit(1);
        curbp  = bp;                            /* Make this current    */
        wheadp = wp;
        curwp  = wp;
        wp->w_wndp  = NULL;                     /* Initialize window    */
        wp->w_bufp  = bp;
        bp->b_nwnd  = 1;                        /* Displayed.           */
        wp->w_linep = bp->b_linep;
        wp->w_dotp  = bp->b_linep;
        wp->w_doto  = 0;
        wp->w_markp = NULL;
        wp->w_marko = 0;
        wp->w_toprow = 0;
        wp->w_ntrows = term.t_nrow-1;           /* "-1" for mode line.  */
        wp->w_force = 0;
        wp->w_flag  = WFMODE|WFHARD;            /* Full.                */
}
        
/*
 * This is the general command execution routine. It handles the fake binding
 * of all the keys to "self-insert". It also clears out the "thisflag" word,
 * and arranges to move it to the "lastflag", so that the next command can
 * look at it. Return the status of command.
 */
execute(c, f, n)
{
        register KEYTAB *ktp;
        register int    status;

        ktp = &keytab[0];                       /* Look in key table.   */
        while (ktp < &keytab[NKEYTAB]) {
                if (ktp->k_code == c) {
                        thisflag = 0;
                        status   = (*ktp->k_fp)(f, n);
                        lastflag = thisflag;
                        return (status);
                }
                ++ktp;
        }

        /*
         * If a space was typed, fill column is defined, the argument is non-
         * negative, and we are now past fill column, perform word wrap.
         */
        if (c == ' ' && fillcol > 0 && n>=0 && getccol(FALSE) > fillcol)
                wrapword();

        if ((c>=0x20 && c<=0x7E)                /* Self inserting.      */
        ||  (c>=0xA0 && c<=0xFE)) {
                if (n <= 0) {                   /* Fenceposts.          */
                        lastflag = 0;
                        return (n<0 ? FALSE : TRUE);
                }
                thisflag = 0;                   /* For the future.      */
                status   = linsert(n, c);
                lastflag = thisflag;
                return (status);
        }
        lastflag = 0;                           /* Fake last flags.     */
        return (FALSE);
}

/*
 * Read in a key.
 * Do the standard keyboard preprocessing. Convert the keys to the internal
 * character set.
 */
getkey()
{
        register int    c;

        c = (*term.t_getchar)();

#if RAINBOW

        if (c & Function_Key)
                {
                int i;

                for (i = 0; i < lk_map_size; i++)
                        if (c == lk_map[i][0])
                                return lk_map[i][1];
                }
        else if (c == Shift + 015) return CTRL | 'J';
        else if (c == Shift + 0x7F) return META | 0x7F;
#endif

        if (c == METACH) {                      /* Apply M- prefix      */
                c = getctl();
                return (META | c);
        }

        if (c>=0x00 && c<=0x1F)                 /* C0 control -> C-     */
                c = CTRL | (c+'@');
        return (c);
}

/*
 * Get a key.
 * Apply control modifications to the read key.
 */
getctl()
{
        register int    c;

        c = (*term.t_getchar)();
        if (c>='a' && c<='z')                   /* Force to upper       */
                c -= 0x20;
        if (c>=0x00 && c<=0x1F)                 /* C0 control -> C-     */
                c = CTRL | (c+'@');
        return (c);
}

/*
 * Fancy quit command, as implemented by Norm. If the current buffer has
 * changed do a write current buffer and exit emacs, otherwise simply exit.
 */
quickexit(f, n)
{
        if ((curbp->b_flag&BFCHG) != 0          /* Changed.             */
        && (curbp->b_flag&BFTEMP) == 0)         /* Real.                */
                filesave(f, n);
        quit(f, n);                             /* conditionally quit   */
}

/*
 * Quit command. If an argument, always quit. Otherwise confirm if a buffer
 * has been changed and not written out. Normally bound to "C-X C-C".
 */
quit(f, n)
{
        register int    s;

        if (f != FALSE                          /* Argument forces it.  */
        || anycb() == FALSE                     /* All buffers clean.   */
        || (s=mlyesno("Quit")) == TRUE) {       /* User says it's OK.   */
                vttidy();
                exit(GOOD);
        }
        return (s);
}

/*
 * Begin a keyboard macro.
 * Error if not at the top level in keyboard processing. Set up variables and
 * return.
 */
ctlxlp(f, n)
{
        if (kbdmip!=NULL || kbdmop!=NULL) {
                mlwrite("Not now");
                return (FALSE);
        }
        mlwrite("[Start macro]");
        kbdmip = &kbdm[0];
        return (TRUE);
}

/*
 * End keyboard macro. Check for the same limit conditions as the above
 * routine. Set up the variables and return to the caller.
 */
ctlxrp(f, n)
{
        if (kbdmip == NULL) {
                mlwrite("Not now");
                return (FALSE);
        }
        mlwrite("[End macro]");
        kbdmip = NULL;
        return (TRUE);
}

/*
 * Execute a macro.
 * The command argument is the number of times to loop. Quit as soon as a
 * command gets an error. Return TRUE if all ok, else FALSE.
 */
ctlxe(f, n)
{
        register int    c;
        register int    af;
        register int    an;
        register int    s;

        if (kbdmip!=NULL || kbdmop!=NULL) {
                mlwrite("Not now");
                return (FALSE);
        }
        if (n <= 0) 
                return (TRUE);
        do {
                kbdmop = &kbdm[0];
                do {
                        af = FALSE;
                        an = 1;
                        if ((c = *kbdmop++) == (CTRL|'U')) {
                                af = TRUE;
                                an = *kbdmop++;
                                c  = *kbdmop++;
                        }
                        s = TRUE;
                } while (c!=(CTLX|')') && (s=execute(c, af, an))==TRUE);
                kbdmop = NULL;
        } while (s==TRUE && --n);
        return (s);
}

/*
 * Abort.
 * Beep the beeper. Kill off any keyboard macro, etc., that is in progress.
 * Sometimes called as a routine, to do general aborting of stuff.
 */
ctrlg(f, n)
{
        (*term.t_beep)();
        if (kbdmip != NULL) {
                kbdm[0] = (CTLX|')');
                kbdmip  = NULL;
        }
        return (ABORT);
}


==================================================
random.c
==================================================
/*
 * This file contains the command processing functions for a number of random
 * commands. There is no functional grouping here, for sure.
 */

#include        <stdio.h>
#include        "ed.h"

int     tabsize;                        /* Tab size (0: use real tabs)  */

/*
 * Set fill column to n. 
 */
setfillcol(f, n)
{
        fillcol = n;
        return(TRUE);
}

/*
 * Display the current position of the cursor, in origin 1 X-Y coordinates,
 * the character that is under the cursor (in octal), and the fraction of the
 * text that is before the cursor. The displayed column is not the current
 * column, but the column that would be used on an infinite width display.
 * Normally this is bound to "C-X =".
 */
showcpos(f, n)
{
        register LINE   *clp;
        register long   nch;
        register int    cbo;
        register long   nbc;
        register int    cac;
        register int    ratio;
        register int    col;
        register int    i;
        register int    c;

        clp = lforw(curbp->b_linep);            /* Grovel the data.     */
        cbo = 0;
        nch = 0;
        for (;;) {
                if (clp==curwp->w_dotp && cbo==curwp->w_doto) {
                        nbc = nch;
                        if (cbo == llength(clp))
                                cac = '\n';
                        else
                                cac = lgetc(clp, cbo);
                }
                if (cbo == llength(clp)) {
                        if (clp == curbp->b_linep)
                                break;
                        clp = lforw(clp);
                        cbo = 0;
                } else
                        ++cbo;
                ++nch;
        }
        col = getccol(FALSE);                   /* Get real column.     */
        ratio = 0;                              /* Ratio before dot.    */
        if (nch != 0)
                ratio = (100L*nbc) / nch;
        mlwrite("X=%d Y=%d CH=0x%x .=%D (%d%% of %D)",
                col+1, currow+1, cac, nbc, ratio, nch);
        return (TRUE);
}

/*
 * Return current column.  Stop at first non-blank given TRUE argument.
 */
getccol(bflg)
int bflg;
{
        register int c, i, col;
        col = 0;
        for (i=0; i<curwp->w_doto; ++i) {
                c = lgetc(curwp->w_dotp, i);
                if (c!=' ' && c!='\t' && bflg)
                        break;
                if (c == '\t')
                        col |= 0x07;
                else if (c<0x20 || c==0x7F)
                        ++col;
                ++col;
        }
        return(col);
}

/*
 * Twiddle the two characters on either side of dot. If dot is at the end of
 * the line twiddle the two characters before it. Return with an error if dot
 * is at the beginning of line; it seems to be a bit pointless to make this
 * work. This fixes up a very common typo with a single stroke. Normally bound
 * to "C-T". This always works within a line, so "WFEDIT" is good enough.
 */
twiddle(f, n)
{
        register LINE   *dotp;
        register int    doto;
        register int    cl;
        register int    cr;

        dotp = curwp->w_dotp;
        doto = curwp->w_doto;
        if (doto==llength(dotp) && --doto<0)
                return (FALSE);
        cr = lgetc(dotp, doto);
        if (--doto < 0)
                return (FALSE);
        cl = lgetc(dotp, doto);
        lputc(dotp, doto+0, cr);
        lputc(dotp, doto+1, cl);
        lchange(WFEDIT);
        return (TRUE);
}

/*
 * Quote the next character, and insert it into the buffer. All the characters
 * are taken literally, with the exception of the newline, which always has
 * its line splitting meaning. The character is always read, even if it is
 * inserted 0 times, for regularity. Bound to "M-Q" (for me) and "C-Q" (for
 * Rich, and only on terminals that don't need XON-XOFF).
 */
quote(f, n)
{
        register int    s;
        register int    c;

        c = (*term.t_getchar)();
        if (n < 0)
                return (FALSE);
        if (n == 0)
                return (TRUE);
        if (c == '\n') {
                do {
                        s = lnewline();
                } while (s==TRUE && --n);
                return (s);
        }
        return (linsert(n, c));
}

/*
 * Set tab size if given non-default argument (n <> 1).  Otherwise, insert a
 * tab into file.  If given argument, n, of zero, change to true tabs.
 * If n > 1, simulate tab stop every n-characters using spaces. This has to be
 * done in this slightly funny way because the tab (in ASCII) has been turned
 * into "C-I" (in 10 bit code) already. Bound to "C-I".
 */
tab(f, n)
{
        if (n < 0)
                return (FALSE);
        if (n == 0 || n > 1) {
                tabsize = n;
                return(TRUE);
        }
        if (! tabsize)
                return(linsert(1, '\t'));
        return(linsert(tabsize - (getccol(FALSE) % tabsize), ' '));
}

/*
 * Open up some blank space. The basic plan is to insert a bunch of newlines,
 * and then back up over them. Everything is done by the subcommand
 * procerssors. They even handle the looping. Normally this is bound to "C-O".
 */
openline(f, n)
{
        register int    i;
        register int    s;

        if (n < 0)
                return (FALSE);
        if (n == 0)
                return (TRUE);
        i = n;                                  /* Insert newlines.     */
        do {
                s = lnewline();
        } while (s==TRUE && --i);
        if (s == TRUE)                          /* Then back up overtop */
                s = backchar(f, n);             /* of them all.         */
        return (s);
}

/*
 * Insert a newline. Bound to "C-M". If you are at the end of the line and the
 * next line is a blank line, just move into the blank line. This makes "C-O"
 * and "C-X C-O" work nicely, and reduces the ammount of screen update that
 * has to be done. This would not be as critical if screen update were a lot
 * more efficient.
 */
newline(f, n)
{
        int nicol;
        register LINE   *lp;
        register int    s;

        if (n < 0)
                return (FALSE);
        while (n--) {
                lp = curwp->w_dotp;
                if (llength(lp) == curwp->w_doto
                && lp != curbp->b_linep
                && llength(lforw(lp)) == 0) {
                        if ((s=forwchar(FALSE, 1)) != TRUE)
                                return (s);
                } else if ((s=lnewline()) != TRUE)
                        return (s);
        }
        return (TRUE);
}

/*
 * Delete blank lines around dot. What this command does depends if dot is
 * sitting on a blank line. If dot is sitting on a blank line, this command
 * deletes all the blank lines above and below the current line. If it is
 * sitting on a non blank line then it deletes all of the blank lines after
 * the line. Normally this command is bound to "C-X C-O". Any argument is
 * ignored.
 */
deblank(f, n)
{
        register LINE   *lp1;
        register LINE   *lp2;
        register int    nld;

        lp1 = curwp->w_dotp;
        while (llength(lp1)==0 && (lp2=lback(lp1))!=curbp->b_linep)
                lp1 = lp2;
        lp2 = lp1;
        nld = 0;
        while ((lp2=lforw(lp2))!=curbp->b_linep && llength(lp2)==0)
                ++nld;
        if (nld == 0)
                return (TRUE);
        curwp->w_dotp = lforw(lp1);
        curwp->w_doto = 0;
        return (ldelete(nld));
}

/*
 * Insert a newline, then enough tabs and spaces to duplicate the indentation
 * of the previous line. Assumes tabs are every eight characters. Quite simple.
 * Figure out the indentation of the current line. Insert a newline by calling
 * the standard routine. Insert the indentation by inserting the right number
 * of tabs and spaces. Return TRUE if all ok. Return FALSE if one of the
 * subcomands failed. Normally bound to "C-J".
 */
indent(f, n)
{
        register int    nicol;
        register int    c;
        register int    i;

        if (n < 0)
                return (FALSE);
        while (n--) {
                nicol = 0;
                for (i=0; i<llength(curwp->w_dotp); ++i) {
                        c = lgetc(curwp->w_dotp, i);
                        if (c!=' ' && c!='\t')
                                break;
                        if (c == '\t')
                                nicol |= 0x07;
                        ++nicol;
                }
                if (lnewline() == FALSE
                || ((i=nicol/8)!=0 && linsert(i, '\t')==FALSE)
                || ((i=nicol%8)!=0 && linsert(i,  ' ')==FALSE))
                        return (FALSE);
        }
        return (TRUE);
}

/*
 * Delete forward. This is real easy, because the basic delete routine does
 * all of the work. Watches for negative arguments, and does the right thing.
 * If any argument is present, it kills rather than deletes, to prevent loss
 * of text if typed with a big argument. Normally bound to "C-D".
 */
forwdel(f, n)
{
        if (n < 0)
                return (backdel(f, -n));
        if (f != FALSE) {                       /* Really a kill.       */
                if ((lastflag&CFKILL) == 0)
                        kdelete();
                thisflag |= CFKILL;
        }
        return (ldelete(n, f));
}

/*
 * Delete backwards. This is quite easy too, because it's all done with other
 * functions. Just move the cursor back, and delete forwards. Like delete
 * forward, this actually does a kill if presented with an argument. Bound to
 * both "RUBOUT" and "C-H".
 */
backdel(f, n)
{
        register int    s;

        if (n < 0)
                return (forwdel(f, -n));
        if (f != FALSE) {                       /* Really a kill.       */
                if ((lastflag&CFKILL) == 0)
                        kdelete();
                thisflag |= CFKILL;
        }
        if ((s=backchar(f, n)) == TRUE)
                s = ldelete(n, f);
        return (s);
}

/*
 * Kill text. If called without an argument, it kills from dot to the end of
 * the line, unless it is at the end of the line, when it kills the newline.
 * If called with an argument of 0, it kills from the start of the line to dot.
 * If called with a positive argument, it kills from dot forward over that
 * number of newlines. If called with a negative argument it kills backwards
 * that number of newlines. Normally bound to "C-K".
 */
kill(f, n)
{
        register int    chunk;
        register LINE   *nextp;

        if ((lastflag&CFKILL) == 0)             /* Clear kill buffer if */
                kdelete();                      /* last wasn't a kill.  */
        thisflag |= CFKILL;
        if (f == FALSE) {
                chunk = llength(curwp->w_dotp)-curwp->w_doto;
                if (chunk == 0)
                        chunk = 1;
        } else if (n == 0) {
                chunk = curwp->w_doto;
                curwp->w_doto = 0;
        } else if (n > 0) {
                chunk = llength(curwp->w_dotp)-curwp->w_doto+1;
                nextp = lforw(curwp->w_dotp);
                while (--n) {
                        if (nextp == curbp->b_linep)
                                return (FALSE);
                        chunk += llength(nextp)+1;
                        nextp = lforw(nextp);
                }
        } else {
                mlwrite("neg kill");
                return (FALSE);
        }
        return (ldelete(chunk, TRUE));
}

/*
 * Yank text back from the kill buffer. This is really easy. All of the work
 * is done by the standard insert routines. All you do is run the loop, and
 * check for errors. Bound to "C-Y". The blank lines are inserted with a call
 * to "newline" instead of a call to "lnewline" so that the magic stuff that
 * happens when you type a carriage return also happens when a carriage return
 * is yanked back from the kill buffer.
 */
yank(f, n)
{
        register int    c;
        register int    i;
        extern   int    kused;

        if (n < 0)
                return (FALSE);
        while (n--) {
                i = 0;
                while ((c=kremove(i)) >= 0) {
                        if (c == '\n') {
                                if (newline(FALSE, 1) == FALSE)
                                        return (FALSE);
                        } else {
                                if (linsert(1, c) == FALSE)
                                        return (FALSE);
                        }
                        ++i;
                }
        }
        return (TRUE);
}

==================================================
region.c
==================================================
/*
 * The routines in this file
 * deal with the region, that magic space
 * between "." and mark. Some functions are
 * commands. Some functions are just for
 * internal use.
 */
#include        <stdio.h>
#include        "ed.h"

/*
 * Kill the region. Ask "getregion"
 * to figure out the bounds of the region.
 * Move "." to the start, and kill the characters.
 * Bound to "C-W".
 */
killregion(f, n)
{
        register int    s;
        REGION          region;

        if ((s=getregion(&region)) != TRUE)
                return (s);
        if ((lastflag&CFKILL) == 0)             /* This is a kill type  */
                kdelete();                      /* command, so do magic */
        thisflag |= CFKILL;                     /* kill buffer stuff.   */
        curwp->w_dotp = region.r_linep;
        curwp->w_doto = region.r_offset;
        return (ldelete(region.r_size, TRUE));
}

/*
 * Copy all of the characters in the
 * region to the kill buffer. Don't move dot
 * at all. This is a bit like a kill region followed
 * by a yank. Bound to "M-W".
 */
copyregion(f, n)
{
        register LINE   *linep;
        register int    loffs;
        register int    s;
        REGION          region;

        if ((s=getregion(&region)) != TRUE)
                return (s);
        if ((lastflag&CFKILL) == 0)             /* Kill type command.   */
                kdelete();
        thisflag |= CFKILL;
        linep = region.r_linep;                 /* Current line.        */
        loffs = region.r_offset;                /* Current offset.      */
        while (region.r_size--) {
                if (loffs == llength(linep)) {  /* End of line.         */
                        if ((s=kinsert('\n')) != TRUE)
                                return (s);
                        linep = lforw(linep);
                        loffs = 0;
                } else {                        /* Middle of line.      */
                        if ((s=kinsert(lgetc(linep, loffs))) != TRUE)
                                return (s);
                        ++loffs;
                }
        }
        return (TRUE);
}

/*
 * Lower case region. Zap all of the upper
 * case characters in the region to lower case. Use
 * the region code to set the limits. Scan the buffer,
 * doing the changes. Call "lchange" to ensure that
 * redisplay is done in all buffers. Bound to 
 * "C-X C-L".
 */
lowerregion(f, n)
{
        register LINE   *linep;
        register int    loffs;
        register int    c;
        register int    s;
        REGION          region;

        if ((s=getregion(&region)) != TRUE)
                return (s);
        lchange(WFHARD);
        linep = region.r_linep;
        loffs = region.r_offset;
        while (region.r_size--) {
                if (loffs == llength(linep)) {
                        linep = lforw(linep);
                        loffs = 0;
                } else {
                        c = lgetc(linep, loffs);
                        if (c>='A' && c<='Z')
                                lputc(linep, loffs, c+'a'-'A');
                        ++loffs;
                }
        }
        return (TRUE);
}

/*
 * Upper case region. Zap all of the lower
 * case characters in the region to upper case. Use
 * the region code to set the limits. Scan the buffer,
 * doing the changes. Call "lchange" to ensure that
 * redisplay is done in all buffers. Bound to 
 * "C-X C-L".
 */
upperregion(f, n)
{
        register LINE   *linep;
        register int    loffs;
        register int    c;
        register int    s;
        REGION          region;

        if ((s=getregion(&region)) != TRUE)
                return (s);
        lchange(WFHARD);
        linep = region.r_linep;
        loffs = region.r_offset;
        while (region.r_size--) {
                if (loffs == llength(linep)) {
                        linep = lforw(linep);
                        loffs = 0;
                } else {
                        c = lgetc(linep, loffs);
                        if (c>='a' && c<='z')
                                lputc(linep, loffs, c-'a'+'A');
                        ++loffs;
                }
        }
        return (TRUE);
}

/*
 * This routine figures out the
 * bounds of the region in the current window, and
 * fills in the fields of the "REGION" structure pointed
 * to by "rp". Because the dot and mark are usually very
 * close together, we scan outward from dot looking for
 * mark. This should save time. Return a standard code.
 * Callers of this routine should be prepared to get
 * an "ABORT" status; we might make this have the
 * conform thing later.
 */
getregion(rp)
register REGION *rp;
{
        register LINE   *flp;
        register LINE   *blp;
        register int    fsize;
        register int    bsize;

        if (curwp->w_markp == NULL) {
                mlwrite("No mark set in this window");
                return (FALSE);
        }
        if (curwp->w_dotp == curwp->w_markp) {
                rp->r_linep = curwp->w_dotp;
                if (curwp->w_doto < curwp->w_marko) {
                        rp->r_offset = curwp->w_doto;
                        rp->r_size = curwp->w_marko-curwp->w_doto;
                } else {
                        rp->r_offset = curwp->w_marko;
                        rp->r_size = curwp->w_doto-curwp->w_marko;
                }
                return (TRUE);
        }
        blp = curwp->w_dotp;
        bsize = curwp->w_doto;
        flp = curwp->w_dotp;
        fsize = llength(flp)-curwp->w_doto+1;
        while (flp!=curbp->b_linep || lback(blp)!=curbp->b_linep) {
                if (flp != curbp->b_linep) {
                        flp = lforw(flp);
                        if (flp == curwp->w_markp) {
                                rp->r_linep = curwp->w_dotp;
                                rp->r_offset = curwp->w_doto;
                                rp->r_size = fsize+curwp->w_marko;
                                return (TRUE);
                        }
                        fsize += llength(flp)+1;
                }
                if (lback(blp) != curbp->b_linep) {
                        blp = lback(blp);
                        bsize += llength(blp)+1;
                        if (blp == curwp->w_markp) {
                                rp->r_linep = blp;
                                rp->r_offset = curwp->w_marko;
                                rp->r_size = bsize - curwp->w_marko;
                                return (TRUE);
                        }
                }
        }
        mlwrite("Bug: lost mark");
        return (FALSE);
}

==================================================
search.c
==================================================
/*
 * The functions in this file implement commands that search in the forward
 * and backward directions. There are no special characters in the search
 * strings. Probably should have a regular expression search, or something
 * like that.
 *
 * REVISION HISTORY:
 *
 * ?    Steve Wilhite, 1-Dec-85
 *      - massive cleanup on code.
 */

#include        <stdio.h>
#include        "ed.h"

/*
 * Search forward. Get a search string from the user, and search, beginning at
 * ".", for the string. If found, reset the "." to be just after the match
 * string, and [perhaps] repaint the display. Bound to "C-S".
 */
forwsearch(f, n)
    {
    register LINE *clp;
    register int cbo;
    register LINE*tlp;
    register int tbo;
    register int c;
    register char *pp;
    register int s;

    if ((s = readpattern("Search")) != TRUE)
        return (s);

    clp = curwp->w_dotp;
    cbo = curwp->w_doto;

    while (clp != curbp->b_linep)
        {
        if (cbo == llength(clp))
            {
            clp = lforw(clp);
            cbo = 0;
            c = '\n';
            }
        else
            c = lgetc(clp, cbo++);

        if (eq(c, pat[0]) != FALSE)
            {
            tlp = clp;
            tbo = cbo;
            pp  = &pat[1];

            while (*pp != 0)
                {
                if (tlp == curbp->b_linep)
                    goto fail;

                if (tbo == llength(tlp))
                    {
                    tlp = lforw(tlp);
                    tbo = 0;
                    c = '\n';
                    }
                else
                    c = lgetc(tlp, tbo++);

                if (eq(c, *pp++) == FALSE)
                    goto fail;
                }

            curwp->w_dotp  = tlp;
            curwp->w_doto  = tbo;
            curwp->w_flag |= WFMOVE;
            return (TRUE);
            }
fail:;
        }

    mlwrite("Not found");
    return (FALSE);
    }

/*
 * Reverse search. Get a search string from the user, and search, starting at
 * "." and proceeding toward the front of the buffer. If found "." is left
 * pointing at the first character of the pattern [the last character that was
 j matched]. Bound to "C-R".
 */
backsearch(f, n)
    {
    register LINE *clp;
    register int cbo;
    register LINE *tlp;
    register int tbo;
    register int c;
    register char *epp;
    register char *pp;
    register int s;

    if ((s = readpattern("Reverse search")) != TRUE)
        return (s);

    for (epp = &pat[0]; epp[1] != 0; ++epp)
        ;

    clp = curwp->w_dotp;
    cbo = curwp->w_doto;

    for (;;)
        {
        if (cbo == 0)
            {
            clp = lback(clp);

            if (clp == curbp->b_linep)
                {
                mlwrite("Not found");
                return (FALSE);
                }

            cbo = llength(clp)+1;
            }

        if (--cbo == llength(clp))
            c = '\n';
        else
            c = lgetc(clp, cbo);

        if (eq(c, *epp) != FALSE)
            {
            tlp = clp;
            tbo = cbo;
            pp  = epp;

            while (pp != &pat[0])
                {
                if (tbo == 0)
                    {
                    tlp = lback(tlp);
                    if (tlp == curbp->b_linep)
                        goto fail;

                    tbo = llength(tlp)+1;
                    }

                if (--tbo == llength(tlp))
                    c = '\n';
                else
                    c = lgetc(tlp, tbo);

                if (eq(c, *--pp) == FALSE)
                    goto fail;
                }

            curwp->w_dotp  = tlp;
            curwp->w_doto  = tbo;
            curwp->w_flag |= WFMOVE;
            return (TRUE);
            }
fail:;
        }
    }

/*
 * Compare two characters. The "bc" comes from the buffer. It has it's case
 * folded out. The "pc" is from the pattern.
 */
eq(bc, pc)
    int bc;
    int pc;
    {
    if (bc>='a' && bc<='z')
        bc -= 0x20;

    if (pc>='a' && pc<='z')
        pc -= 0x20;

    if (bc == pc)
        return (TRUE);

    return (FALSE);
    }

/*
 * Read a pattern. Stash it in the external variable "pat". The "pat" is not
 * updated if the user types in an empty line. If the user typed an empty line,
 * and there is no old pattern, it is an error. Display the old pattern, in the
 * style of Jeff Lomicka. There is some do-it-yourself control expansion.
 */
readpattern(prompt)
    char *prompt;
    {
    register char *cp1;
    register char *cp2;
    register int c;
    register int s;
    char tpat[NPAT+20];

    cp1 = &tpat[0];                     /* Copy prompt */
    cp2 = prompt;

    while ((c = *cp2++) != '\0')
        *cp1++ = c;

    if (pat[0] != '\0')                 /* Old pattern */
        {
        *cp1++ = ' ';
        *cp1++ = '[';
        cp2 = &pat[0];

        while ((c = *cp2++) != 0)
            {
            if (cp1 < &tpat[NPAT+20-6]) /* "??]: \0" */
                {
                if (c<0x20 || c==0x7F) {
                    *cp1++ = '^';
                    c ^= 0x40;
                    }
                else if (c == '%')      /* Map "%" to */
                    *cp1++ = c;         /* "%%". */

                *cp1++ = c;
                }
            }

        *cp1++ = ']';
        }

    *cp1++ = ':';                       /* Finish prompt */
    *cp1++ = ' ';
    *cp1++ = '\0';
    s = mlreply(tpat, tpat, NPAT);      /* Read pattern */

    if (s == TRUE)                      /* Specified */
        strcpy(pat, tpat);
    else if (s == FALSE && pat[0] != 0)         /* CR, but old one */
        s = TRUE;

    return (s);
    }

==================================================
spawn.c
==================================================
/*
 * The routines in this file are called to create a subjob running a command
 * interpreter. This code is a big fat nothing on CP/M-86. You lose.
 */
#include        <stdio.h>
#include        "ed.h"

#if     AMIGA
#define  NEW   1006
#endif

#if     VMS
#define EFN     0                               /* Event flag.          */

#include        <ssdef.h>                       /* Random headers.      */
#include        <stsdef.h>
#include        <descrip.h>
#include        <iodef.h>

extern  int     oldmode[];                      /* In "termio.c"        */
extern  int     newmode[];                      /* In "termio.c"        */
extern  short   iochan;                         /* In "termio.c"        */
#endif

#if     MSDOS
#include        <dos.h>
#endif

#if     V7
#include        <signal.h>
#endif

/*
 * Create a subjob with a copy of the command intrepreter in it. When the
 * command interpreter exits, mark the screen as garbage so that you do a full
 * repaint. Bound to "C-C". The message at the start in VMS puts out a newline.
 * Under some (unknown) condition, you don't get one free when DCL starts up.
 */
spawncli(f, n)
{
#if     AMIGA
        long newcli;

        newcli = Open("CON:1/1/639/199/MicroEmacs Subprocess", NEW);
        mlwrite("[Starting new CLI]");
        sgarbf = TRUE;
        Execute("", newcli, 0);
        Close(newcli);
        return(TRUE);
#endif

#if     V7
        register char *cp;
        char    *getenv();
#endif
#if     VMS
        movecursor(term.t_nrow, 0);             /* In last line.        */
        mlputs("[Starting DCL]\r\n");
        (*term.t_flush)();                      /* Ignore "ttcol".      */
        sgarbf = TRUE;
        return (sys(NULL));                     /* NULL => DCL.         */
#endif
#if     CPM
        mlwrite("Not in CP/M-86");
#endif
#if     MSDOS
        movecursor(term.t_nrow, 0);             /* Seek to last line.   */
        (*term.t_flush)();
        sys("\\command.com", "");               /* Run CLI.             */
        sgarbf = TRUE;
        return(TRUE);
#endif
#if     V7
        movecursor(term.t_nrow, 0);             /* Seek to last line.   */
        (*term.t_flush)();
        ttclose();                              /* stty to old settings */
        if ((cp = getenv("SHELL")) != NULL && *cp != '\0')
                system(cp);
        else
                system("exec /bin/sh");
        sgarbf = TRUE;
        sleep(2);
        ttopen();
        return(TRUE);
#endif
}

/*
 * Run a one-liner in a subjob. When the command returns, wait for a single
 * character to be typed, then mark the screen as garbage so a full repaint is
 * done. Bound to "C-X !".
 */
spawn(f, n)
{
        register int    s;
        char            line[NLINE];
#if     AMIGA
        long newcli;

        newcli = Open("CON:1/1/639/199/MicroEmacs Subprocess", NEW);
        if ((s=mlreply("CLI command: ", line, NLINE)) != TRUE)
                return (s);
        Execute(line,0,newcli);
        Close(newcli);
        while ((*term.t_getchar)() != '\r')     /* Pause.               */
                ;
        sgarbf = TRUE;
        return(TRUE);
#endif
#if     VMS
        if ((s=mlreply("DCL command: ", line, NLINE)) != TRUE)
                return (s);
        (*term.t_putchar)('\n');                /* Already have '\r'    */
        (*term.t_flush)();
        s = sys(line);                          /* Run the command.     */
        mlputs("\r\n\n[End]");                  /* Pause.               */
        (*term.t_flush)();
        while ((*term.t_getchar)() != '\r')
                ;
        sgarbf = TRUE;
        return (s);
#endif
#if     CPM
        mlwrite("Not in CP/M-86");
        return (FALSE);
#endif
#if     MSDOS
        if ((s=mlreply("MS-DOS command: ", line, NLINE)) != TRUE)
                return (s);
        system(line);
        while ((*term.t_getchar)() != '\r')     /* Pause.               */
                ;
        sgarbf = TRUE;
        return (TRUE);
#endif
#if     V7
        if ((s=mlreply("! ", line, NLINE)) != TRUE)
                return (s);
        (*term.t_putchar)('\n');                /* Already have '\r'    */
        (*term.t_flush)();
        ttclose();                              /* stty to old modes    */
        system(line);
        sleep(2);
        ttopen();
        mlputs("[End]");                        /* Pause.               */
        (*term.t_flush)();
        while ((s = (*term.t_getchar)()) != '\r' && s != ' ')
                ;
        sgarbf = TRUE;
        return (TRUE);
#endif
}

#if     VMS
/*
 * Run a command. The "cmd" is a pointer to a command string, or NULL if you
 * want to run a copy of DCL in the subjob (this is how the standard routine
 * LIB$SPAWN works. You have to do wierd stuff with the terminal on the way in
 * and the way out, because DCL does not want the channel to be in raw mode.
 */
sys(cmd)
register char   *cmd;
{
        struct  dsc$descriptor  cdsc;
        struct  dsc$descriptor  *cdscp;
        long    status;
        long    substatus;
        long    iosb[2];

        status = SYS$QIOW(EFN, iochan, IO$_SETMODE, iosb, 0, 0,
                          oldmode, sizeof(oldmode), 0, 0, 0, 0);
        if (status!=SS$_NORMAL || (iosb[0]&0xFFFF)!=SS$_NORMAL)
                return (FALSE);
        cdscp = NULL;                           /* Assume DCL.          */
        if (cmd != NULL) {                      /* Build descriptor.    */
                cdsc.dsc$a_pointer = cmd;
                cdsc.dsc$w_length  = strlen(cmd);
                cdsc.dsc$b_dtype   = DSC$K_DTYPE_T;
                cdsc.dsc$b_class   = DSC$K_CLASS_S;
                cdscp = &cdsc;
        }
        status = LIB$SPAWN(cdscp, 0, 0, 0, 0, 0, &substatus, 0, 0, 0);
        if (status != SS$_NORMAL)
                substatus = status;
        status = SYS$QIOW(EFN, iochan, IO$_SETMODE, iosb, 0, 0,
                          newmode, sizeof(newmode), 0, 0, 0, 0);
        if (status!=SS$_NORMAL || (iosb[0]&0xFFFF)!=SS$_NORMAL)
                return (FALSE);
        if ((substatus&STS$M_SUCCESS) == 0)     /* Command failed.      */
                return (FALSE);
        return (TRUE);
}
#endif

#if     MSDOS
/*
 * This routine, once again by Bob McNamara, is a C translation of the "system"
 * routine in the MWC-86 run time library. It differs from the "system" routine
 * in that it does not unconditionally append the string ".exe" to the end of
 * the command name. We needed to do this because we want to be able to spawn
 * off "command.com". We really do not understand what it does, but if you don't
 * do it exactly "malloc" starts doing very very strange things.
 */
sys(cmd, tail)
char    *cmd;
char    *tail;
{
#if MWC_86
        register unsigned n;
        extern   char     *__end;

        n = __end + 15;
        n >>= 4;
        n = ((n + dsreg() + 16) & 0xFFF0) + 16;
        return(execall(cmd, tail, n));
#endif

#if LATTICE
        return forklp(cmd, tail, NULL);
#endif
}
#endif

==================================================
tcap.c
==================================================
#include <stdio.h>
#include "ed.h"

#if TERMCAP

#define NROW    24
#define NCOL    80
#define BEL     0x07
#define ESC     0x1B

extern int      ttopen();
extern int      ttgetc();
extern int      ttputc();
extern int      ttflush();
extern int      ttclose();
extern int      tcapmove();
extern int      tcapeeol();
extern int      tcapeeop();
extern int      tcapbeep();
extern int      tcapopen();
extern int      tput();
extern char     *tgoto();

#define TCAPSLEN 315

char tcapbuf[TCAPSLEN];
char    PC,
        *CM,
        *CL,
        *CE,
        *UP,
        *CD;


TERM term = {
        NROW-1,
        NCOL,
        &tcapopen,
        &ttclose,
        &ttgetc,
        &ttputc,
        &ttflush,
        &tcapmove,
        &tcapeeol,
        &tcapeeop,
        &tcapbeep
};

tcapopen()

{
        char *getenv();
        char *t, *p, *tgetstr();
        char tcbuf[1024];
        char *tv_stype;
        char err_str[72];

        if ((tv_stype = getenv("TERM")) == NULL)
        {
                puts("Environment variable TERM not defined!");
                exit(1);
        }

        if((tgetent(tcbuf, tv_stype)) != 1)
        {
                sprintf(err_str, "Unknown terminal type %s!", tv_stype);
                puts(err_str);
                exit(1);
        }

        p = tcapbuf;
        t = tgetstr("pc", &p);
        if(t)
                PC = *t;

        CD = tgetstr("cd", &p);
        CM = tgetstr("cm", &p);
        CE = tgetstr("ce", &p);
        UP = tgetstr("up", &p);

        if(CD == NULL || CM == NULL || CE == NULL || UP == NULL)
        {
                puts("Incomplete termcap entry\n");
                exit(1);
        }

        if (p >= &tcapbuf[TCAPSLEN])
        {
                puts("Terminal description too big!\n");
                exit(1);
        }
        ttopen();
}
tcapmove(row, col)
register int row, col;
{
        putpad(tgoto(CM, col, row));
}

tcapeeol()
{
        putpad(CE);
}

tcapeeop()
{
        putpad(CD);
}

tcapbeep()
{
        ttputc(BEL);
}

putpad(str)
char    *str;
{
        tputs(str, 1, ttputc);
}

putnpad(str, n)
char    *str;
{
        tputs(str, n, ttputc);
}
#endif TERMCAP

==================================================
termio.c
==================================================
/*
 * The functions in this file negotiate with the operating system for
 * characters, and write characters in a barely buffered fashion on the display.
 * All operating systems.
 */
#include        <stdio.h>
#include        "ed.h"

#if     AMIGA
#define NEW 1006
#define LEN 1

static long terminal;
#endif

#if     VMS
#include        <stsdef.h>
#include        <ssdef.h>
#include        <descrip.h>
#include        <iodef.h>
#include        <ttdef.h>

#define NIBUF   128                     /* Input  buffer size           */
#define NOBUF   1024                    /* MM says bug buffers win!     */
#define EFN     0                       /* Event flag                   */

char    obuf[NOBUF];                    /* Output buffer                */
int     nobuf;                          /* # of bytes in above          */
char    ibuf[NIBUF];                    /* Input buffer                 */
int     nibuf;                          /* # of bytes in above          */
int     ibufi;                          /* Read index                   */
int     oldmode[2];                     /* Old TTY mode bits            */
int     newmode[2];                     /* New TTY mode bits            */
short   iochan;                         /* TTY I/O channel              */
#endif

#if     CPM
#include        <bdos.h>
#endif

#if     MSDOS
#undef  LATTICE
#include        <dos.h>
#endif

#if RAINBOW
#include "rainbow.h"
#endif

#if V7
#include        <sgtty.h>               /* for stty/gtty functions */
struct  sgttyb  ostate;                 /* saved tty state */
struct  sgttyb  nstate;                 /* values for editor mode */
#endif

/*
 * This function is called once to set up the terminal device streams.
 * On VMS, it translates SYS$INPUT until it finds the terminal, then assigns
 * a channel to it and sets it raw. On CPM it is a no-op.
 */
ttopen()
{
#if     AMIGA
        terminal = Open("RAW:1/1/639/199/MicroEmacs", NEW);
#endif
#if     VMS
        struct  dsc$descriptor  idsc;
        struct  dsc$descriptor  odsc;
        char    oname[40];
        int     iosb[2];
        int     status;

        odsc.dsc$a_pointer = "SYS$INPUT";
        odsc.dsc$w_length  = strlen(odsc.dsc$a_pointer);
        odsc.dsc$b_dtype   = DSC$K_DTYPE_T;
        odsc.dsc$b_class   = DSC$K_CLASS_S;
        idsc.dsc$b_dtype   = DSC$K_DTYPE_T;
        idsc.dsc$b_class   = DSC$K_CLASS_S;
        do {
                idsc.dsc$a_pointer = odsc.dsc$a_pointer;
                idsc.dsc$w_length  = odsc.dsc$w_length;
                odsc.dsc$a_pointer = &oname[0];
                odsc.dsc$w_length  = sizeof(oname);
                status = LIB$SYS_TRNLOG(&idsc, &odsc.dsc$w_length, &odsc);
                if (status!=SS$_NORMAL && status!=SS$_NOTRAN)
                        exit(status);
                if (oname[0] == 0x1B) {
                        odsc.dsc$a_pointer += 4;
                        odsc.dsc$w_length  -= 4;
                }
        } while (status == SS$_NORMAL);
        status = SYS$ASSIGN(&odsc, &iochan, 0, 0);
        if (status != SS$_NORMAL)
                exit(status);
        status = SYS$QIOW(EFN, iochan, IO$_SENSEMODE, iosb, 0, 0,
                          oldmode, sizeof(oldmode), 0, 0, 0, 0);
        if (status!=SS$_NORMAL || (iosb[0]&0xFFFF)!=SS$_NORMAL)
                exit(status);
        newmode[0] = oldmode[0];
        newmode[1] = oldmode[1] | TT$M_PASSALL | TT$M_NOECHO;
        status = SYS$QIOW(EFN, iochan, IO$_SETMODE, iosb, 0, 0,
                          newmode, sizeof(newmode), 0, 0, 0, 0);
        if (status!=SS$_NORMAL || (iosb[0]&0xFFFF)!=SS$_NORMAL)
                exit(status);
#endif
#if     CPM
#endif
#if     MSDOS
#endif
#if     V7
        gtty(1, &ostate);                       /* save old state */
        gtty(1, &nstate);                       /* get base of new state */
        nstate.sg_flags |= RAW;
        nstate.sg_flags &= ~(ECHO|CRMOD);       /* no echo for now... */
        stty(1, &nstate);                       /* set mode */
#endif
}

/*
 * This function gets called just before we go back home to the command
 * interpreter. On VMS it puts the terminal back in a reasonable state.
 * Another no-operation on CPM.
 */
ttclose()
{
#if     AMIGA
        Close(terminal);
#endif
#if     VMS
        int     status;
        int     iosb[1];

        ttflush();
        status = SYS$QIOW(EFN, iochan, IO$_SETMODE, iosb, 0, 0,
                 oldmode, sizeof(oldmode), 0, 0, 0, 0);
        if (status!=SS$_NORMAL || (iosb[0]&0xFFFF)!=SS$_NORMAL)
                exit(status);
        status = SYS$DASSGN(iochan);
        if (status != SS$_NORMAL)
                exit(status);
#endif
#if     CPM
#endif
#if     MSDOS
#endif
#if     V7
        stty(1, &ostate);
#endif
}

/*
 * Write a character to the display. On VMS, terminal output is buffered, and
 * we just put the characters in the big array, after checking for overflow.
 * On CPM terminal I/O unbuffered, so we just write the byte out. Ditto on
 * MS-DOS (use the very very raw console output routine).
 */
ttputc(c)
#if     AMIGA
        char c;
#endif
{
#if     AMIGA
        Write(terminal, &c, LEN);
#endif
#if     VMS
        if (nobuf >= NOBUF)
                ttflush();
        obuf[nobuf++] = c;
#endif

#if     CPM
        bios(BCONOUT, c, 0);
#endif

#if     MSDOS & CWC86
        dosb(CONDIO, c, 0);
#endif

#if RAINBOW
        Put_Char(c);                    /* fast video */
#endif

#if     V7
        fputc(c, stdout);
#endif
}

/*
 * Flush terminal buffer. Does real work where the terminal output is buffered
 * up. A no-operation on systems where byte at a time terminal I/O is done.
 */
ttflush()
{
#if     AMIGA
#endif
#if     VMS
        int     status;
        int     iosb[2];

        status = SS$_NORMAL;
        if (nobuf != 0) {
                status = SYS$QIOW(EFN, iochan, IO$_WRITELBLK|IO$M_NOFORMAT,
                         iosb, 0, 0, obuf, nobuf, 0, 0, 0, 0);
                if (status == SS$_NORMAL)
                        status = iosb[0] & 0xFFFF;
                nobuf = 0;
        }
        return (status);
#endif
#if     CPM
#endif
#if     MSDOS
#endif
#if     V7
        fflush(stdout);
#endif
}

/*
 * Read a character from the terminal, performing no editing and doing no echo
 * at all. More complex in VMS that almost anyplace else, which figures. Very
 * simple on CPM, because the system can do exactly what you want.
 */
ttgetc()
{
#if     AMIGA
        char ch;

        Read(terminal, &ch, LEN);
        return (int) ch;
#endif
#if     VMS
        int     status;
        int     iosb[2];
        int     term[2];

        while (ibufi >= nibuf) {
                ibufi = 0;
                term[0] = 0;
                term[1] = 0;
                status = SYS$QIOW(EFN, iochan, IO$_READLBLK|IO$M_TIMED,
                         iosb, 0, 0, ibuf, NIBUF, 0, term, 0, 0);
                if (status != SS$_NORMAL)
                        exit(status);
                status = iosb[0] & 0xFFFF;
                if (status!=SS$_NORMAL && status!=SS$_TIMEOUT)
                        exit(status);
                nibuf = (iosb[0]>>16) + (iosb[1]>>16);
                if (nibuf == 0) {
                        status = SYS$QIOW(EFN, iochan, IO$_READLBLK,
                                 iosb, 0, 0, ibuf, 1, 0, term, 0, 0);
                        if (status != SS$_NORMAL
                        || (status = (iosb[0]&0xFFFF)) != SS$_NORMAL)
                                exit(status);
                        nibuf = (iosb[0]>>16) + (iosb[1]>>16);
                }
        }
        return (ibuf[ibufi++] & 0xFF);          /* Allow multinational  */
#endif

#if     CPM
        return (biosb(BCONIN, 0, 0));
#endif

#if RAINBOW
        int Ch;

        while ((Ch = Read_Keyboard()) < 0);

        if ((Ch & Function_Key) == 0)
                if (!((Ch & 0xFF) == 015 || (Ch & 0xFF) == 0177))
                        Ch &= 0xFF;

        return Ch;
#endif

#if     MSDOS & MWC86
        return (dosb(CONRAW, 0, 0));
#endif

#if     V7
        return(fgetc(stdin));
#endif
}

==================================================
vt52.c
==================================================
/*
 * The routines in this file
 * provide support for VT52 style terminals
 * over a serial line. The serial I/O services are
 * provided by routines in "termio.c". It compiles
 * into nothing if not a VT52 style device. The
 * bell on the VT52 is terrible, so the "beep"
 * routine is conditionalized on defining BEL.
 */
#include        <stdio.h>
#include        "ed.h"

#if     VT52

#define NROW    24                      /* Screen size.                 */
#define NCOL    80                      /* Edit if you want to.         */
#define BIAS    0x20                    /* Origin 0 coordinate bias.    */
#define ESC     0x1B                    /* ESC character.               */
#define BEL     0x07                    /* ascii bell character         */

extern  int     ttopen();               /* Forward references.          */
extern  int     ttgetc();
extern  int     ttputc();
extern  int     ttflush();
extern  int     ttclose();
extern  int     vt52move();
extern  int     vt52eeol();
extern  int     vt52eeop();
extern  int     vt52beep();
extern  int     vt52open();

/*
 * Dispatch table. All the
 * hard fields just point into the
 * terminal I/O code.
 */
TERM    term    = {
        NROW-1,
        NCOL,
        &vt52open,
        &ttclose,
        &ttgetc,
        &ttputc,
        &ttflush,
        &vt52move,
        &vt52eeol,
        &vt52eeop,
        &vt52beep
};

vt52move(row, col)
{
        ttputc(ESC);
        ttputc('Y');
        ttputc(row+BIAS);
        ttputc(col+BIAS);
}

vt52eeol()
{
        ttputc(ESC);
        ttputc('K');
}

vt52eeop()
{
        ttputc(ESC);
        ttputc('J');
}

vt52beep()
{
#ifdef  BEL
        ttputc(BEL);
        ttflush();
#endif
}

#endif

vt52open()
{
#if     V7
        register char *cp;
        char *getenv();

        if ((cp = getenv("TERM")) == NULL) {
                puts("Shell variable TERM not defined!");
                exit(1);
        }
        if (strcmp(cp, "vt52") != 0 && strcmp(cp, "z19") != 0) {
                puts("Terminal type not 'vt52'or 'z19' !");
                exit(1);
        }
#endif
        ttopen();
}

==================================================
window.c
==================================================

/*
 * Window management. Some of the functions are internal, and some are
 * attached to keys that the user actually types.
 */

#include        <stdio.h>
#include        "ed.h"

/*
 * Reposition dot in the current window to line "n". If the argument is
 * positive, it is that line. If it is negative it is that line from the
 * bottom. If it is 0 the window is centered (this is what the standard
 * redisplay code does). With no argument it defaults to 1. Bound to M-!.
 * Because of the default, it works like in Gosling.
 */
reposition(f, n)
    {
    curwp->w_force = n;
    curwp->w_flag |= WFFORCE;
    return (TRUE);
    }

/*
 * Refresh the screen. With no argument, it just does the refresh. With an
 * argument it recenters "." in the current window. Bound to "C-L".
 */
refresh(f, n)
    {
    if (f == FALSE)
        sgarbf = TRUE;
    else
        {
        curwp->w_force = 0;             /* Center dot. */
        curwp->w_flag |= WFFORCE;
        }

    return (TRUE);
    }

/*
 * The command make the next window (next => down the screen) the current
 * window. There are no real errors, although the command does nothing if
 * there is only 1 window on the screen. Bound to "C-X C-N".
 */
nextwind(f, n)
    {
    register WINDOW *wp;

    if ((wp = curwp->w_wndp) == NULL)
        wp = wheadp;

    curwp = wp;
    curbp = wp->w_bufp;
    return (TRUE);
    }

/*
 * This command makes the previous window (previous => up the screen) the
 * current window. There arn't any errors, although the command does not do a
 * lot if there is 1 window.
 */
prevwind(f, n)
    {
    register WINDOW *wp1;
    register WINDOW *wp2;

    wp1 = wheadp;
    wp2 = curwp;

    if (wp1 == wp2)
        wp2 = NULL;

    while (wp1->w_wndp != wp2)
        wp1 = wp1->w_wndp;

    curwp = wp1;
    curbp = wp1->w_bufp;
    return (TRUE);
    }

/*
 * This command moves the current window down by "arg" lines. Recompute the
 * top line in the window. The move up and move down code is almost completely
 * the same; most of the work has to do with reframing the window, and picking
 * a new dot. We share the code by having "move down" just be an interface to
 * "move up". Magic. Bound to "C-X C-N".
 */
mvdnwind(f, n)
    int n;
    {
    return (mvupwind(f, -n));
    }

/*
 * Move the current window up by "arg" lines. Recompute the new top line of
 * the window. Look to see if "." is still on the screen. If it is, you win.
 * If it isn't, then move "." to center it in the new framing of the window
 * (this command does not really move "."; it moves the frame). Bound to
 * "C-X C-P".
 */
mvupwind(f, n)
    int n;
    {
    register LINE *lp;
    register int i;

    lp = curwp->w_linep;

    if (n < 0)
        {
        while (n++ && lp!=curbp->b_linep)
            lp = lforw(lp);
        }
    else
        {
        while (n-- && lback(lp)!=curbp->b_linep)
            lp = lback(lp);
        }

    curwp->w_linep = lp;
    curwp->w_flag |= WFHARD;            /* Mode line is OK. */

    for (i = 0; i < curwp->w_ntrows; ++i)
        {
        if (lp == curwp->w_dotp)
            return (TRUE);
        if (lp == curbp->b_linep)
            break;
        lp = lforw(lp);
        }

    lp = curwp->w_linep;
    i  = curwp->w_ntrows/2;

    while (i-- && lp != curbp->b_linep)
        lp = lforw(lp);

    curwp->w_dotp  = lp;
    curwp->w_doto  = 0;
    return (TRUE);
    }

/*
 * This command makes the current window the only window on the screen. Bound
 * to "C-X 1". Try to set the framing so that "." does not have to move on the
 * display. Some care has to be taken to keep the values of dot and mark in
 * the buffer structures right if the distruction of a window makes a buffer
 * become undisplayed.
 */
onlywind(f, n)
{
        register WINDOW *wp;
        register LINE   *lp;
        register int    i;

        while (wheadp != curwp) {
                wp = wheadp;
                wheadp = wp->w_wndp;
                if (--wp->w_bufp->b_nwnd == 0) {
                        wp->w_bufp->b_dotp  = wp->w_dotp;
                        wp->w_bufp->b_doto  = wp->w_doto;
                        wp->w_bufp->b_markp = wp->w_markp;
                        wp->w_bufp->b_marko = wp->w_marko;
                }
                free((char *) wp);
        }
        while (curwp->w_wndp != NULL) {
                wp = curwp->w_wndp;
                curwp->w_wndp = wp->w_wndp;
                if (--wp->w_bufp->b_nwnd == 0) {
                        wp->w_bufp->b_dotp  = wp->w_dotp;
                        wp->w_bufp->b_doto  = wp->w_doto;
                        wp->w_bufp->b_markp = wp->w_markp;
                        wp->w_bufp->b_marko = wp->w_marko;
                }
                free((char *) wp);
        }
        lp = curwp->w_linep;
        i  = curwp->w_toprow;
        while (i!=0 && lback(lp)!=curbp->b_linep) {
                --i;
                lp = lback(lp);
        }
        curwp->w_toprow = 0;
        curwp->w_ntrows = term.t_nrow-1;
        curwp->w_linep  = lp;
        curwp->w_flag  |= WFMODE|WFHARD;
        return (TRUE);
}

/*
 * Split the current window. A window smaller than 3 lines cannot be split.
 * The only other error that is possible is a "malloc" failure allocating the
 * structure for the new window. Bound to "C-X 2".
 */
splitwind(f, n)
{
        register WINDOW *wp;
        register LINE   *lp;
        register int    ntru;
        register int    ntrl;
        register int    ntrd;
        register WINDOW *wp1;
        register WINDOW *wp2;

        if (curwp->w_ntrows < 3) {
                mlwrite("Cannot split a %d line window", curwp->w_ntrows);
                return (FALSE);
        }
        if ((wp = (WINDOW *) malloc(sizeof(WINDOW))) == NULL) {
                mlwrite("Cannot allocate WINDOW block");
                return (FALSE);
        }
        ++curbp->b_nwnd;                        /* Displayed twice.     */
        wp->w_bufp  = curbp;
        wp->w_dotp  = curwp->w_dotp;
        wp->w_doto  = curwp->w_doto;
        wp->w_markp = curwp->w_markp;
        wp->w_marko = curwp->w_marko;
        wp->w_flag  = 0;
        wp->w_force = 0;
        ntru = (curwp->w_ntrows-1) / 2;         /* Upper size           */
        ntrl = (curwp->w_ntrows-1) - ntru;      /* Lower size           */
        lp = curwp->w_linep;
        ntrd = 0;
        while (lp != curwp->w_dotp) {
                ++ntrd;
                lp = lforw(lp);
        }
        lp = curwp->w_linep;
        if (ntrd <= ntru) {                     /* Old is upper window. */
                if (ntrd == ntru)               /* Hit mode line.       */
                        lp = lforw(lp);
                curwp->w_ntrows = ntru;
                wp->w_wndp = curwp->w_wndp;
                curwp->w_wndp = wp;
                wp->w_toprow = curwp->w_toprow+ntru+1;
                wp->w_ntrows = ntrl;
        } else {                                /* Old is lower window  */
                wp1 = NULL;
                wp2 = wheadp;
                while (wp2 != curwp) {
                        wp1 = wp2;
                        wp2 = wp2->w_wndp;
                }
                if (wp1 == NULL)
                        wheadp = wp;
                else
                        wp1->w_wndp = wp;
                wp->w_wndp   = curwp;
                wp->w_toprow = curwp->w_toprow;
                wp->w_ntrows = ntru;
                ++ntru;                         /* Mode line.           */
                curwp->w_toprow += ntru;
                curwp->w_ntrows  = ntrl;
                while (ntru--)
                        lp = lforw(lp);
        }
        curwp->w_linep = lp;                    /* Adjust the top lines */
        wp->w_linep = lp;                       /* if necessary.        */
        curwp->w_flag |= WFMODE|WFHARD;
        wp->w_flag |= WFMODE|WFHARD;
        return (TRUE);
}

/*
 * Enlarge the current window. Find the window that loses space. Make sure it
 * is big enough. If so, hack the window descriptions, and ask redisplay to do
 * all the hard work. You don't just set "force reframe" because dot would
 * move. Bound to "C-X Z".
 */
enlargewind(f, n)
{
        register WINDOW *adjwp;
        register LINE   *lp;
        register int    i;

        if (n < 0)
                return (shrinkwind(f, -n));
        if (wheadp->w_wndp == NULL) {
                mlwrite("Only one window");
                return (FALSE);
        }
        if ((adjwp=curwp->w_wndp) == NULL) {
                adjwp = wheadp;
                while (adjwp->w_wndp != curwp)
                        adjwp = adjwp->w_wndp;
        }
        if (adjwp->w_ntrows <= n) {
                mlwrite("Impossible change");
                return (FALSE);
        }
        if (curwp->w_wndp == adjwp) {           /* Shrink below.        */
                lp = adjwp->w_linep;
                for (i=0; i<n && lp!=adjwp->w_bufp->b_linep; ++i)
                        lp = lforw(lp);
                adjwp->w_linep  = lp;
                adjwp->w_toprow += n;
        } else {                                /* Shrink above.        */
                lp = curwp->w_linep;
                for (i=0; i<n && lback(lp)!=curbp->b_linep; ++i)
                        lp = lback(lp);
                curwp->w_linep  = lp;
                curwp->w_toprow -= n;
        }
        curwp->w_ntrows += n;
        adjwp->w_ntrows -= n;
        curwp->w_flag |= WFMODE|WFHARD;
        adjwp->w_flag |= WFMODE|WFHARD;
        return (TRUE);
}

/*
 * Shrink the current window. Find the window that gains space. Hack at the
 * window descriptions. Ask the redisplay to do all the hard work. Bound to
 * "C-X C-Z".
 */
shrinkwind(f, n)
{
        register WINDOW *adjwp;
        register LINE   *lp;
        register int    i;

        if (n < 0)
                return (enlargewind(f, -n));
        if (wheadp->w_wndp == NULL) {
                mlwrite("Only one window");
                return (FALSE);
        }
        if ((adjwp=curwp->w_wndp) == NULL) {
                adjwp = wheadp;
                while (adjwp->w_wndp != curwp)
                        adjwp = adjwp->w_wndp;
        }
        if (curwp->w_ntrows <= n) {
                mlwrite("Impossible change");
                return (FALSE);
        }
        if (curwp->w_wndp == adjwp) {           /* Grow below.          */
                lp = adjwp->w_linep;
                for (i=0; i<n && lback(lp)!=adjwp->w_bufp->b_linep; ++i)
                        lp = lback(lp);
                adjwp->w_linep  = lp;
                adjwp->w_toprow -= n;
        } else {                                /* Grow above.          */
                lp = curwp->w_linep;
                for (i=0; i<n && lp!=curbp->b_linep; ++i)
                        lp = lforw(lp);
                curwp->w_linep  = lp;
                curwp->w_toprow += n;
        }
        curwp->w_ntrows -= n;
        adjwp->w_ntrows += n;
        curwp->w_flag |= WFMODE|WFHARD;
        adjwp->w_flag |= WFMODE|WFHARD;
        return (TRUE);
}

/*
 * Pick a window for a pop-up. Split the screen if there is only one window.
 * Pick the uppermost window that isn't the current window. An LRU algorithm
 * might be better. Return a pointer, or NULL on error.
 */
WINDOW  *
wpopup()
{
        register WINDOW *wp;

        if (wheadp->w_wndp == NULL              /* Only 1 window        */
        && splitwind(FALSE, 0) == FALSE)        /* and it won't split   */
                return (NULL);
        wp = wheadp;                            /* Find window to use   */
        while (wp!=NULL && wp==curwp)
                wp = wp->w_wndp;
        return (wp);
}


OK
==================================================
word.c
==================================================
/*
 * The routines in this file implement commands that work word at a time.
 * There are all sorts of word mode commands. If I do any sentence and/or
 * paragraph mode commands, they are likely to be put in this file.
 */

#include        <stdio.h>
#include        "ed.h"


/* Word wrap on n-spaces. Back-over whatever precedes the point on the current
 * line and stop on the first word-break or the beginning of the line. If we
 * reach the beginning of the line, jump back to the end of the word and start
 * a new line.  Otherwise, break the line at the word-break, eat it, and jump
 * back to the end of the word.
 *      NOTE:  This function may leaving trailing blanks.
 * Returns TRUE on success, FALSE on errors.
 */
wrapword(n)
int n;
{
        register int cnt, oldp;
        oldp = curwp->w_dotp;
        cnt = -1;
        do {                            
                cnt++;
                if (! backchar(NULL, 1))
                        return(FALSE);
        }
        while (! inword());
        if (! backword(NULL, 1))
                return(FALSE);
        if (oldp == (int) (curwp->w_dotp && curwp->w_doto)) {
                if (! backdel(NULL, 1))
                        return(FALSE);
                if (! newline(NULL, 1))
                        return(FALSE);
        }
        return(forwword(NULL, 1) && forwchar(NULL, cnt));
}
                                
/*
 * Move the cursor backward by "n" words. All of the details of motion are
 * performed by the "backchar" and "forwchar" routines. Error if you try to
 * move beyond the buffers.
 */
backword(f, n)
{
        if (n < 0)
                return (forwword(f, -n));
        if (backchar(FALSE, 1) == FALSE)
                return (FALSE);
        while (n--) {
                while (inword() == FALSE) {
                        if (backchar(FALSE, 1) == FALSE)
                                return (FALSE);
                }
                while (inword() != FALSE) {
                        if (backchar(FALSE, 1) == FALSE)
                                return (FALSE);
                }
        }
        return (forwchar(FALSE, 1));
}

/*
 * Move the cursor forward by the specified number of words. All of the motion
 * is done by "forwchar". Error if you try and move beyond the buffer's end.
 */
forwword(f, n)
{
        if (n < 0)
                return (backword(f, -n));
        while (n--) {
                while (inword() == FALSE) {
                        if (forwchar(FALSE, 1) == FALSE)
                                return (FALSE);
                }
                while (inword() != FALSE) {
                        if (forwchar(FALSE, 1) == FALSE)
                                return (FALSE);
                }
        }
        return (TRUE);
}

/*
 * Move the cursor forward by the specified number of words. As you move,
 * convert any characters to upper case. Error if you try and move beyond the
 * end of the buffer. Bound to "M-U".
 */
upperword(f, n)
{
        register int    c;

        if (n < 0)
                return (FALSE);
        while (n--) {
                while (inword() == FALSE) {
                        if (forwchar(FALSE, 1) == FALSE)
                                return (FALSE);
                }
                while (inword() != FALSE) {
                        c = lgetc(curwp->w_dotp, curwp->w_doto);
                        if (c>='a' && c<='z') {
                                c -= 'a'-'A';
                                lputc(curwp->w_dotp, curwp->w_doto, c);
                                lchange(WFHARD);
                        }
                        if (forwchar(FALSE, 1) == FALSE)
                                return (FALSE);
                }
        }
        return (TRUE);
}

/*
 * Move the cursor forward by the specified number of words. As you move
 * convert characters to lower case. Error if you try and move over the end of
 * the buffer. Bound to "M-L".
 */
lowerword(f, n)
{
        register int    c;

        if (n < 0)
                return (FALSE);
        while (n--) {
                while (inword() == FALSE) {
                        if (forwchar(FALSE, 1) == FALSE)
                                return (FALSE);
                }
                while (inword() != FALSE) {
                        c = lgetc(curwp->w_dotp, curwp->w_doto);
                        if (c>='A' && c<='Z') {
                                c += 'a'-'A';
                                lputc(curwp->w_dotp, curwp->w_doto, c);
                                lchange(WFHARD);
                        }
                        if (forwchar(FALSE, 1) == FALSE)
                                return (FALSE);
                }
        }
        return (TRUE);
}

/*
 * Move the cursor forward by the specified number of words. As you move
 * convert the first character of the word to upper case, and subsequent
 * characters to lower case. Error if you try and move past the end of the
 * buffer. Bound to "M-C".
 */
capword(f, n)
{
        register int    c;

        if (n < 0)
                return (FALSE);
        while (n--) {
                while (inword() == FALSE) {
                        if (forwchar(FALSE, 1) == FALSE)
                                return (FALSE);
                }
                if (inword() != FALSE) {
                        c = lgetc(curwp->w_dotp, curwp->w_doto);
                        if (c>='a' && c<='z') {
                                c -= 'a'-'A';
                                lputc(curwp->w_dotp, curwp->w_doto, c);
                                lchange(WFHARD);
                        }
                        if (forwchar(FALSE, 1) == FALSE)
                                return (FALSE);
                        while (inword() != FALSE) {
                                c = lgetc(curwp->w_dotp, curwp->w_doto);
                                if (c>='A' && c<='Z') {
                                        c += 'a'-'A';
                                        lputc(curwp->w_dotp, curwp->w_doto, c);
                                        lchange(WFHARD);
                                }
                                if (forwchar(FALSE, 1) == FALSE)
                                        return (FALSE);
                        }
                }
        }
        return (TRUE);
}

/*
 * Kill forward by "n" words. Remember the location of dot. Move forward by
 * the right number of words. Put dot back where it was and issue the kill
 * command for the right number of characters. Bound to "M-D".
 */
delfword(f, n)
{
        register int    size;
        register LINE   *dotp;
        register int    doto;

        if (n < 0)
                return (FALSE);
        dotp = curwp->w_dotp;
        doto = curwp->w_doto;
        size = 0;
        while (n--) {
                while (inword() == FALSE) {
                        if (forwchar(FALSE, 1) == FALSE)
                                return (FALSE);
                        ++size;
                }
                while (inword() != FALSE) {
                        if (forwchar(FALSE, 1) == FALSE)
                                return (FALSE);
                        ++size;
                }
        }
        curwp->w_dotp = dotp;
        curwp->w_doto = doto;
        return (ldelete(size, TRUE));
}

/*
 * Kill backwards by "n" words. Move backwards by the desired number of words,
 * counting the characters. When dot is finally moved to its resting place,
 * fire off the kill command. Bound to "M-Rubout" and to "M-Backspace".
 */
delbword(f, n)
{
        register int    size;

        if (n < 0)
                return (FALSE);
        if (backchar(FALSE, 1) == FALSE)
                return (FALSE);
        size = 0;
        while (n--) {
                while (inword() == FALSE) {
                        if (backchar(FALSE, 1) == FALSE)
                                return (FALSE);
                        ++size;
                }
                while (inword() != FALSE) {
                        if (backchar(FALSE, 1) == FALSE)
                                return (FALSE);
                        ++size;
                }
        }
        if (forwchar(FALSE, 1) == FALSE)
                return (FALSE);
        return (ldelete(size, TRUE));
}

/*
 * Return TRUE if the character at dot is a character that is considered to be
 * part of a word. The word character list is hard coded. Should be setable.
 */
inword()
{
        register int    c;

        if (curwp->w_doto == llength(curwp->w_dotp))
                return (FALSE);
        c = lgetc(curwp->w_dotp, curwp->w_doto);
        if (c>='a' && c<='z')
                return (TRUE);
        if (c>='A' && c<='Z')
                return (TRUE);
        if (c>='0' && c<='9')
                return (TRUE);
        if (c=='$' || c=='_')                   /* For identifiers      */
                return (TRUE);
        return (FALSE);
}

==================================================
ed.h
==================================================
/*
 * This file is the general header file for all parts of the MicroEMACS
 * display editor. It contains definitions used by everyone, and it contains
 * the stuff you have to edit to create a version of the editor for a specific
 * operating system and terminal.
 */

#define AMIGA   1                       /* AmigaDOS, Lattice            */
#define ST520   0                       /* ST520, TOS                   */
#define MWC86   0
#define V7      0                       /* V7 UN*X or Coherent          */
#define VMS     0                       /* VAX/VMS                      */
#define CPM     0                       /* CP/M-86                      */

#ifndef MSDOS                           /* Already defined for Lattice  */
#define MSDOS   0                       /* MS-DOS                       */
#endif

#define ANSI    1
#define VT52    0                       /* VT52 terminal (Zenith).      */
#define VT100   0                       /* Handle VT100 style keypad.   */
#define LK201   0                       /* Handle LK201 style keypad.   */
#define RAINBOW 0                       /* Use Rainbow fast video.      */
#define TERMCAP 0                       /* Use TERMCAP                  */

#define CVMVAS  1                       /* C-V, M-V arg. in screens.    */

#define NFILEN  80                      /* # of bytes, file name        */
#define NBUFN   16                      /* # of bytes, buffer name      */
#define NLINE   256                     /* # of bytes, line             */
#define NKBDM   256                     /* # of strokes, keyboard macro */
#define NPAT    80                      /* # of bytes, pattern          */
#define HUGE    1000                    /* Huge number                  */

#define AGRAVE  0x60                    /* M- prefix,   Grave (LK201)   */
#define METACH  0x1B                    /* M- prefix,   Control-[, ESC  */
#define CTMECH  0x1C                    /* C-M- prefix, Control-\       */
#define EXITCH  0x1D                    /* Exit level,  Control-]       */
#define CTRLCH  0x1E                    /* C- prefix,   Control-^       */
#define HELPCH  0x1F                    /* Help key,    Control-_       */

#define CTRL    0x0100                  /* Control flag, or'ed in       */
#define META    0x0200                  /* Meta flag, or'ed in          */
#define CTLX    0x0400                  /* ^X flag, or'ed in            */

#define FALSE   0                       /* False, no, bad, etc.         */
#define TRUE    1                       /* True, yes, good, etc.        */
#define ABORT   2                       /* Death, ^G, abort, etc.       */

#define FIOSUC  0                       /* File I/O, success.           */
#define FIOFNF  1                       /* File I/O, file not found.    */
#define FIOEOF  2                       /* File I/O, end of file.       */
#define FIOERR  3                       /* File I/O, error.             */

#define CFCPCN  0x0001                  /* Last command was C-P, C-N    */
#define CFKILL  0x0002                  /* Last command was a kill      */

/*
 * There is a window structure allocated for every active display window. The
 * windows are kept in a big list, in top to bottom screen order, with the
 * listhead at "wheadp". Each window contains its own values of dot and mark.
 * The flag field contains some bits that are set by commands to guide
 * redisplay; although this is a bit of a compromise in terms of decoupling,
 * the full blown redisplay is just too expensive to run for every input
 * character. 
 */
typedef struct  WINDOW {
        struct  WINDOW *w_wndp;         /* Next window                  */
        struct  BUFFER *w_bufp;         /* Buffer displayed in window   */
        struct  LINE *w_linep;          /* Top line in the window       */
        struct  LINE *w_dotp;           /* Line containing "."          */
        short   w_doto;                 /* Byte offset for "."          */
        struct  LINE *w_markp;          /* Line containing "mark"       */
        short   w_marko;                /* Byte offset for "mark"       */
        char    w_toprow;               /* Origin 0 top row of window   */
        char    w_ntrows;               /* # of rows of text in window  */
        char    w_force;                /* If NZ, forcing row.          */
        char    w_flag;                 /* Flags.                       */
}       WINDOW;

#define WFFORCE 0x01                    /* Window needs forced reframe  */
#define WFMOVE  0x02                    /* Movement from line to line   */
#define WFEDIT  0x04                    /* Editing within a line        */
#define WFHARD  0x08                    /* Better to a full display     */
#define WFMODE  0x10                    /* Update mode line.            */

/*
 * Text is kept in buffers. A buffer header, described below, exists for every
 * buffer in the system. The buffers are kept in a big list, so that commands
 * that search for a buffer by name can find the buffer header. There is a
 * safe store for the dot and mark in the header, but this is only valid if
 * the buffer is not being displayed (that is, if "b_nwnd" is 0). The text for
 * the buffer is kept in a circularly linked list of lines, with a pointer to
 * the header line in "b_linep".
 */
typedef struct  BUFFER {
        struct  BUFFER *b_bufp;         /* Link to next BUFFER          */
        struct  LINE *b_dotp;           /* Link to "." LINE structure   */
        short   b_doto;                 /* Offset of "." in above LINE  */
        struct  LINE *b_markp;          /* The same as the above two,   */
        short   b_marko;                /* but for the "mark"           */
        struct  LINE *b_linep;          /* Link to the header LINE      */
        char    b_nwnd;                 /* Count of windows on buffer   */
        char    b_flag;                 /* Flags                        */
        char    b_fname[NFILEN];        /* File name                    */
        char    b_bname[NBUFN];         /* Buffer name                  */
}       BUFFER;

#define BFTEMP  0x01                    /* Internal temporary buffer    */
#define BFCHG   0x02                    /* Changed since last write     */

/*
 * The starting position of a region, and the size of the region in
 * characters, is kept in a region structure.  Used by the region commands.
 */
typedef struct  {
        struct  LINE *r_linep;          /* Origin LINE address.         */
        short   r_offset;               /* Origin LINE offset.          */
        short   r_size;                 /* Length in characters.        */
}       REGION;

/*
 * All text is kept in circularly linked lists of "LINE" structures. These
 * begin at the header line (which is the blank line beyond the end of the
 * buffer). This line is pointed to by the "BUFFER". Each line contains a the
 * number of bytes in the line (the "used" size), the size of the text array,
 * and the text. The end of line is not stored as a byte; it's implied. Future
 * additions will include update hints, and a list of marks into the line.
 */
typedef struct  LINE {
        struct  LINE *l_fp;             /* Link to the next line        */
        struct  LINE *l_bp;             /* Link to the previous line    */
        short   l_size;                 /* Allocated size               */
        short   l_used;                 /* Used size                    */
        char    l_text[1];              /* A bunch of characters.       */
}       LINE;

#define lforw(lp)       ((lp)->l_fp)
#define lback(lp)       ((lp)->l_bp)
#define lgetc(lp, n)    ((lp)->l_text[(n)]&0xFF)
#define lputc(lp, n, c) ((lp)->l_text[(n)]=(c))
#define llength(lp)     ((lp)->l_used)

/*
 * The editor communicates with the display using a high level interface. A
 * "TERM" structure holds useful variables, and indirect pointers to routines
 * that do useful operations. The low level get and put routines are here too.
 * This lets a terminal, in addition to having non standard commands, have
 * funny get and put character code too. The calls might get changed to
 * "termp->t_field" style in the future, to make it possible to run more than
 * one terminal type.
 */  
typedef struct  {
        short   t_nrow;                 /* Number of rows.              */
        short   t_ncol;                 /* Number of columns.           */
        int     (*t_open)();            /* Open terminal at the start.  */
        int     (*t_close)();           /* Close terminal at end.       */
        int     (*t_getchar)();         /* Get character from keyboard. */
        int     (*t_putchar)();         /* Put character to display.    */
        int     (*t_flush)();           /* Flush output buffers.        */
        int     (*t_move)();            /* Move the cursor, origin 0.   */
        int     (*t_eeol)();            /* Erase to end of line.        */
        int     (*t_eeop)();            /* Erase to end of page.        */
        int     (*t_beep)();            /* Beep.                        */
}       TERM;

extern  int     fillcol;                /* Fill column                  */
extern  int     currow;                 /* Cursor row                   */
extern  int     curcol;                 /* Cursor column                */
extern  int     thisflag;               /* Flags, this command          */
extern  int     lastflag;               /* Flags, last command          */
extern  int     curgoal;                /* Goal for C-P, C-N            */
extern  int     mpresf;                 /* Stuff in message line        */
extern  int     sgarbf;                 /* State of screen unknown      */
extern  WINDOW  *curwp;                 /* Current window               */
extern  BUFFER  *curbp;                 /* Current buffer               */
extern  WINDOW  *wheadp;                /* Head of list of windows      */
extern  BUFFER  *bheadp;                /* Head of list of buffers      */
extern  BUFFER  *blistp;                /* Buffer for C-X C-B           */
extern  short   kbdm[];                 /* Holds kayboard macro data    */
extern  short   *kbdmip;                /* Input pointer for above      */
extern  short   *kbdmop;                /* Output pointer for above     */
extern  char    pat[];                  /* Search pattern               */
extern  TERM    term;                   /*(Terminal information.        */

extern  BUFFER  *bfind();               /* Lookup a buffer by name      */
extern  WINDOW  *wpopup();              /* Pop up window creation       */
extern  LINE    *lalloc();              /* Allocate a line              */

-- 
-----------
George M. Jones		{cbosgd,ihnp4}!osu-eddie!george
Work Phone:		george@ohio-state.csnet
(614) 457-8600		CompuServe: 70003,2443
