[net.sources] TVX: repost 2a of 7

wampler@unmvax.UUCP (01/21/86)

#--------CUT---------CUT---------CUT---------CUT--------#
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#                                                       #
# This is a shell archive file.  To extract files:      #
#                                                       #
#    1)	Make a directory (like tvx) for the files.      #
#    2) Write a file, such as "filen.shar", containing  #
#       this archive file into the directory.           #
#    3) Type "sh file.shar".  Do not use csh.           #
#                                                       #
#########################################################
#
#
echo Extracting tvx_1.c:
sed 's/^X//' >tvx_1.c <<\SHAR_EOF
X/* ------------------------ tvx_1.c ------------------------------------- */
X/* ========================================================================
X
X	TVX - A full screen editor in C
X
X	Originally developed by:
X
X		Dr. Bruce E. Wampler
X		University of New Mexico
X		Department of Computer Science
X		Farris Engineering Center
X		Albuquerque, NM 87131
X
X		uucp:   ..{ucbvax | gatech | ihnp4!lanl}!unmvax!wampler
X
X	Public Domain version released July 1, 1985
X		Direct comments, bug reports, suggestions to
X		Bruce Wampler at above address.
X
X	Converted from Ratfor to C January 1981 (note: since the editor
X	    was originally in Ratfor, there are certain remnants of the
X	    original structure left over.  There are a lot of things that
X	    could have been done better if written in C originally.
X	    Note also that this editor was originally designed in
X	    1979 when TECO was state of the art.  The influence of
X	    TECO on this editor will be apparent to anyone who has
X	    used TECO.
X
X	    So it goes.
X
X
X	PLEASE! If you are making additional modifications, use the
X	    indentation scheme used here (line up {,}'s!!!) instead
X	    of the unmaintainable indentation used by K&R!.
X	    Also, please mark your changes with initials and date!
X
X	Description of files required: (names lower case on unix)
X
X	TVX_1.C	   - main part of code (part 1), mostly os/terminal independent
X	TVX_2.C	   - main part of code (part 2), mostly os/terminal independent
X	TVX_LEX.C  - defaults, some os dependent stuff in here.  Major
X		     changes in defaults can be fixed by recompiling this file.
X	TVX_IO.C   - almost all I/O, including screen, confined to this file.
X	TVX_LIB.C  - misc library routines needed by TVX.
X	TVX_IBM.C  - IBM-PC specific code, specifically the screen driver
X	  (TVX_IBM.ASM - hand optimized version of TVX_IBM.C)
X	TVX_UNIX.C - contains unix specific code, including termcap driver
X	TVX_CFG.C  - used to build CONFIG.TVX file for -c switch
X        TVX_PTCH.C - used to permanently patch tvx with config file
X
X	TVX_DEFS.IC - #define's for version, os, terminal, defaults
X        TVX_GLBL.IC - global data structures
X	TVX_TERM.IC - definitions for various terminals and systems
X
X	Most distributions will contain other useful files as well.
X
X============================================================================ */
X
X#include "tvx_defs.ic"		/* note tv_defs.ic will #include stdio.h */
X#include "tvx_glbl.ic"
X
X/* =============================>>> MAIN <<<============================= */
X  main (argc,argv)
X  int argc;
X  char *argv[];
X  {
X
X    checkos();		/* check operating system version */
X    force_tty = FALSE;	/* won't usually force tty mode */
X
X    tvinit();
X    ttinit();		/* initialize tt: */
X    trmini();		/* init terminal if needed */
X    csrcmd();		/* make cursor command cursor */
X
X    fopenx(argc,argv);	/* open the file, maybe change switches */
X
X    tvidefs();		/* set defaults */
X    opnbak();		/* may or may not be null routine */
X
X    edit();		/* edit the file */
X
X    clobak();		/* may be null routine */
X
X    file_exit();	/* clean up files */
X
X    ttymode = FALSE;
X
X    if (*dest_file)
X	remark(dest_file);	/* echo final file name */
X    else
X      {
X	prompt("R/O, no changes: ") ; remark(orig_file);
X      }
X
X    reset();		/* reset anything necessary */
X    quit();
X  }
X
X/* =============================>>> ASK <<<============================= */
X  ask(msg,rply,rcnt)
X  char *msg,*rply;
X  int rcnt;
X  {			/* get a reply, via tty if necessary */
X    int oldtty;
X
X    oldtty = ttymode;
X    ttymode = FALSE;	/* force echo on */
X    prompt(msg);
X    reply(rply,rcnt);
X    ttymode = oldtty;	/* back how it was */
X  }
X
X/* =============================>>> BEGLIN <<<============================= */
X  beglin()
X  {  /* beglin - move cursor to beginning of current line */
X
X    SLOW int xf;
X
X    curchr = *(lines+curlin) + 1;	/* point to current character */
X    xf = findx();	/* this line needed to make the next */
X			/* call eval order independent, if you wondered */
X    tvxy(xf,tvy);	/* and move cursor */
X  }
X
X/* =============================>>> BOTPAG <<<============================= */
X  botpag()
X  { /* botpag - move cursor to bottom of current page (buffer) */
X
X    curlin = nxtlin-1;		/* the last real line of text */
X    curchr = *(lines+curlin) + 1; /* the first char of that line */
X    endlin();			/* goto end of the line */
X    newscr();			/* update the screen */
X  }
X
X/* ============================>>> CHK_RPT_NR <<<============================ */
X  chk_rpt_nr(val)
X  int val;
X  {		/* see if val is in valid range */
X
X    if (val < 0 || val > REPEATBUFS)	/* out of range */
X      {
X	tverrb("Bad rpt buff # ");
X	return (FALSE);
X      }
X    else
X	return (TRUE);
X  }
X
X/* =============================>>> CMDERR <<<============================= */
X  cmderr(chr)
X  char chr;
X  {	/* cmderr - invalid command entered */
X
X    static char badcmd[] = "Bad command:   ";
X
X    if (chr >= ' ')
X      {
X	badcmd[13] = chr; 	/* stick in after : */
X	badcmd[14] = ' ';
X      }
X    else
X      {
X	badcmd[13] = '^';
X	badcmd[14] = chr + '@';
X      }
X    tverrb(badcmd);
X  }
X
X/* =============================>>> COMBIN <<<============================= */
X  combin()
X  { /* combin - combine current line with next line
X		update screen -	cursor assumed to be on curlin */
X
X    SLOW int to,from,xf;
X    SLOW BUFFINDEX newl,k1,k2;
X
X    if (curlin+1 >= nxtlin)		/* can't combine */
X	return (FALSE);
X    if (nxtsav-nxtchr < ALMOSTOUT)	/* check if need g.c. */
X	if (! gbgcol())
X	    return (FALSE);
X    newl = nxtchr;			/* where next char goes */
X    stcopy(buff,*(lines+curlin),buff,&nxtchr); /* copy over current line */
X    curchr = nxtchr;			/* update the curchr */
X    k1 = *(lines+curlin);	  	/* we will kill this line */
X    *(lines+curlin) = newl;		/* remember where it is */
X    stcopy(buff,*(lines+curlin+1)+1,buff,&nxtchr); /* append the next line */
X    ++nxtchr;				/* fix nxtchr */
X    to = curlin+1;
X    k2 = *(lines+to);			/* we will kill this line */
X    for (from=curlin+2; from < nxtlin ; )	/* copy line to end */
X      {
X	*(lines+to++) = *(lines+from++);
X      }
X    --nxtlin;		/* update line ptr */
X    kline(k1);		/* kill the old lines now */
X    kline(k2);
X    if (tvdlin <= dsplin)	/* not at end of buffer */
X      {
X	tvescr();		/* erase rest of screen */
X	tvxy(1,tvy);	/* fix it up */
X	tvtype(curlin,min(tvlins-tvdlin+1,nxtlin-curlin));
X      }
X    else			/* at end of buffer */
X	newscr();
X
X    xf = findx();
X    tvxy(xf,tvy); /* home cursor */
X
X    return (TRUE);
X  }
X
X/* =============================>>> CTRLCH <<<============================= */
X  ctrlch(chr)
X  char chr;
X  { /* ctrlch - echoes a control character for search and lex */
X
X    if (chr >= ' ')
X	tvcout(chr);	/* echo as is */
X    else if (chr == CR)		/* carriage return may be special */
X      {
X	tvcout(CR);
X#ifdef USELF
X	tvcout(LF);	/*$$$ some machines need LF */
X#endif
X      }
X    else if (chr == ESC)	/* escape as $ */
X	tvcout('$');
X    else			/* echo most chars as '^x' */
X      {
X	tvcout('^');
X	tvcout(chr+'@');
X      }
X  }
X
X/* =============================>>> DELNXT <<<============================= */
X  int delnxt(cnt)
X  int cnt;
X  {  /* delnxt - delete next n characters  */
X
X    char clower();
X    static char chdel;
X    SLOW int abscnt,newx;
X    SLOW BUFFINDEX to;
X    SLOW char ans[2];
X    FAST int i;
X
X    abscnt = cnt;	/* remember absolute value of cnt */
X    if (cnt > 100 || cnt < -100)		/* make sure about this! */
X      {
X	tvclr();
X	ask("Kill that many for sure? (y/n) ",ans,1);
X	verify(1);
X	if (clower(ans[0]) != 'y')
X	    return (TRUE);
X       }
X
X    if (cnt > 0)		/* deleting forewards */
X      {
X	chdel = *(buff+curchr); /* remember the char we are deleting */
X	for (i=1; curlin < nxtlin && i <= cnt; ++i) /* don't pass end of buff */
X	  {
X	    if (*(buff+curchr)==ENDLINE)	/* combine when end of line */
X	      {
X		if (! combin())
X		  {
X		    return (FALSE);
X		  }
X	      }
X	    else		/* deleting one character */
X	      {
X		to=curchr;	/* overwrite current line */
X		stcopy(buff,curchr+1,buff,&to); /* copy the rest of the line */
X		for (++to; *(buff+to) != BEGLINE && to < nxtchr; ++to)
X		    *(buff+to)=GARBAGE; /* mark the garbage characters */
X	      }
X	  }
X      }
X    else if (cnt < 0)		/* deleting backwards */
X      {
X	abscnt=(-cnt);
X	chdel = *(buff+curchr-1); /* remember the char we are deleting */
X	for (i=cnt; curlin >= 1 && i<0; ++i)	/* don't go past start */
X	  {
X	    if (*(buff+curchr-1)==BEGLINE)	/* deleting line separator */
X	      {
X		if (curlin > 1) 	/* not past beginning */
X		  {
X		    dwnlin(-1);		/* go up one line */
X		    endlin();		/* get end of the line */
X		    if (!combin())	/* and combine */
X		      {
X			return (FALSE);
X		      }
X		  }
X	      }
X	    else			/* killing a normal character */
X	      {
X		to=curchr-1;		/* overwrite in place */
X		stcopy(buff,curchr,buff,&to); /* copy the rest of the line */
X		for (++to; *(buff+to)!=BEGLINE && to < nxtchr; ++to)
X		    *(buff+to)=GARBAGE; /* mark the garbage characters */
X		--curchr;
X	      }
X	  }
X      }
X    newx=findx();		/* where cursor will go */
X    tvxy(newx,tvy);		/* reposition cursor */
X    if (chdel < ' ' || abscnt != 1)
X	tvelin();		/* erase rest of the line */
X    else			/* need to check for tabs following */
X      {
X	for (i = curchr ; *(buff+i)!=ENDLINE ; ++i)
X	    if (*(buff+i) < ' ')
X	      {
X		tvelin();	/* need to erase the line */
X		break;
X	      }
X      }
X    tvtyln(curchr);		/* retype the rest */
X    if (chdel >= ' ' && abscnt == 1 && last_col_out < tvcols)
X	tvcout(' ');		/* "erase" last char on line */
X    tvxy(newx,tvy);		/* restore the cursor */
X
X    return (TRUE);
X  }
X
X/* =============================>>> DWNCOL <<<============================= */
X  dwncol(cnt)
X  int cnt;
X  { /* dwncol - move down in column */
X
X    SLOW int curcol,l,oldef,needns;
X
X    needns = FALSE;
X    if (leftmg > 1)		/* handle right virtual screen different */
X      {
X	oldef=echof;
X	needns = TRUE;
X	echof = FALSE;
X      }
X
X    if (oldlex==VDOWNCOL || oldlex==VUPCOL)	/* several in a row? */
X	curcol=oldcol;		/* pick up old value */
X    else
X      {
X	curcol = curchr - *(lines+curlin);	/* calculate the current column */
X	oldcol = curcol;
X      }
X    dwnlin(cnt);		/* go down given lines */
X    if (curlin>=1 && curlin<nxtlin && curcol>1)	/* not at ends? */
X      {
X	l = strlen(buff + ((*(lines+curlin)) + 1) );
X	right(min(curcol-1,l));
X      }
X
X    if (needns)			/* needed new screen */
X      {
X	echof=oldef;
X	newscr();
X      }
X  }
X
X/* =============================>>> DWNLIN <<<============================= */
X  dwnlin(cnt)
X  int cnt;
X  { /* dwnlin - move dot down cnt lines */
X
X    SLOW int oldlin,change;
X
X    if (curlin==nxtlin-1 && cnt > 0)	/* down from last line? */
X      {
X	endlin();
X	return;
X      }
X    oldlin=curlin;		/* remember where we started from */
X    curlin=max(min(curlin+cnt,nxtlin-1),1);	/* move down lines */
X    curchr = *(lines+curlin)+1;	/* point to the current character */
X    change=curlin-oldlin;	/* calculate how many lines changed */
X    update(change);		/* update the screen */
X
X  }
X
X/* =============================>>> EDIT   <<<============================= */
X  edit()
X  { /*	edit - main editing routine */
X
X    SLOW int lexval,lexcnt,succ, lastln, itmp;
X    SLOW int noteloc[10], ni, lex_def;
X
X    static int ins_set[] =
X      {
X	VINSERT, VOPENLINE, VQUIT, VABORT, VFBEGIN, VGET, VYANK, 0
X      };
X
X    static int jump_set[] =	/* commands to not reset jump memory */
X      {
X	VJUMP, VMEMORY, VHELP, VNOTELOC, VPRINTS, 0
X      };
X
X    static char lexchr;
X
X    startm();
X    remark("Reading file...");
X
X    rdpage();			/* read a page into the buffer */
X
X    tvclr();			/* clear the screen */
X
X    if (curlin >= 1)
X	tvtype(curlin,tvlins);	/* type out lines */
X
X    tvxy(1,1);			/* and rehome the cursor */
X    waserr = FALSE;		/* no errors to erase yet */
X
X    if (curlin<1)
X	tverr("Buffer empty");
X
X    lexval = UNKNOWN;		/* so can remember 1st time through */
X    useprint = FALSE;		/* not to printer */
X    succ=TRUE;			/* assume success initially */
X
X    lastln = curlin;		/* remember where we were */
X    for (ni = 0 ; ni < 10 ; noteloc[ni++] = curlin)
X	;			/* init noteloc */
X    do
X      {
X	oldlex = lexval;		/* remember last command */
X	if (! succ)
X	    echof = TRUE;		/* resume echo when error */
X	lex_def = lex(&lexval,&lexcnt,&lexchr,succ);	/* get command input */
X	if (waserr)
X	    fixend();
X	waserr=FALSE;
X	succ=TRUE;
X	if (lexval == UNKNOWN)
X	  {
X	    cmderr(lexchr);
X	    succ = FALSE;	/* announce failure to lex */
X	  }
X	else
X	  {
X	    if (curlin < 1)	/* make sure legal command for empty buffer */
X	      {
X
X		if (!inset(lexval,ins_set))
X		  {
X		    tverrb("Can't, buffer empty. Insert 1st ");
X		    succ=FALSE;
X		    continue;
X		  }
X	      }
X	    if (!inset(lexval,jump_set))
X		lastln=curlin;		/* let user look at help w/o changing */
X
X	    switch (lexval)
X	    {
Xcase 1: 			/* right */
X	    right(lexcnt);
X	    break;
Xcase 2: 			/* left */
X	    right(-lexcnt);
X	    break;
Xcase 3: 			/* down line */
X	    dwnlin(lexcnt);
X	    break;
Xcase 4: 			/* up line */
X	    dwnlin(-lexcnt);
X	    break;
Xcase 5: 			/* down in column */
X	    dwncol(lexcnt);
X	    break;
Xcase 6: 			/* up in column */
X	    dwncol(-lexcnt);
X	    break;
Xcase 7: 			/* delete last character */
X	    succ = delnxt(-lexcnt);
X	    break;
Xcase 8: 			/* delete next character */
X	    succ = delnxt(lexcnt);
X	    break;
Xcase 9: 			/* insert */
X	    succ = insert(lexcnt,lex_def);
X	    break;
Xcase 10:			/* kill a line */
X	    killin(lexcnt);
X	    break;
Xcase 11:			/* kill rest of line */
X	    krest();
X	    break;
Xcase 12:			/* kill previous part of line */
X	    kprev();
X	    break;
Xcase 13:			/* move to beginning of line */
X	    beglin();
X	    break;
Xcase 14:			/* move to end of the line */
X	    endlin();
X	    break;
Xcase 15:			/* search for a pattern */
X	    succ = search(lexcnt,TRUE);
X	    break;
Xcase 16:			/* search for next part of a pattern */
X	    succ = snext(lexcnt,TRUE);
X	    break;
Xcase 17:			/* flip screen */
X	    dwnlin(min(lexcnt*tvlins,nxtlin-curlin+1));
X	    break;
Xcase 18:			/* goto top of page */
X	    toppag();
X	    break;
Xcase 19:			/* goto to bottom of page */
X	    botpag();
X	    break;
Xcase 20:			/* goto real beginning of the file */
X	    succ = fbeg();
X	    break;
Xcase 21:			/* verify */
X	    verify(lexcnt);
X	    break;
Xcase 22:			/* open new line */
X	    openln(lexcnt);
X	    succ = insert(1,TRUE); /* go into insert mode, insert mode */
X	    break;
Xcase 23:			/* delete last thing manipulated */
X	    succ = rmvlst();
X	    break;
Xcase 24:			/* save lines in move buffer */
X	    succ = save(lexcnt,FALSE);
X	    break;
Xcase 25:			/* get move buffer */
X	    succ = getsav();
X	    break;
Xcase 26:			/* read in next page of file */
X	    wtpage(lexcnt);	/* write out the current page */
X	    succ = rdpage();	/* read in the next */
X	    tvclr();
X	    if (succ || lexcnt < 0)
X		verify(1);
X	    break;
Xcase 27:			/* append external file to save buffer */
X	    succ = addfil(lexcnt);
X	    break;
Xcase 28:			/* quit */
X	    tvclr();
X	    remark("Exit");
X	    goto lquit;
Xcase 29:			/* search again */
X	    succ = search(lexcnt,FALSE); /* FALSE => don't read search string */
X	    break;
Xcase 30:			/* execute repeat buffer again */
X	    if (lexcnt != 1)
X		echof=FALSE;	/* turn off echo */
X	    rptcnt[rptuse] = lexcnt > 0 ? lexcnt : (-lexcnt);
X	    break;
Xcase 31:			/* print memory status, etc. */
X	    memory();
X	    break;
Xcase 32:			/* change a parameter */
X	    setpar(lexcnt);
X	    break;
Xcase 33:			/* remove last and enter insert mode */
X	    if ((succ = rmvlst()))
X		succ = insert(1,TRUE);
X	    break;
Xcase 34:			/* unkill last line killed */
X	    succ = unkill();
X	    break;
Xcase 35:			/* jump over a word */
X	    wordr(lexcnt);
X	    break;
Xcase 36:			/* neg jump over word */
X	    wordr(-lexcnt);
X	    break;
Xcase 37:			/* append to save buffer */
X	    succ = save(lexcnt,TRUE);
X	    break;
Xcase 38:			/* print screen */
X	    scrprint();
X	    break;
Xcase 39:			/* show repeat buffer + help*/
X	    shoset();
X	    break;
Xcase 40:			/* flip screen half page */
X	    dwnlin( min((lexcnt*tvlins)/2 , nxtlin-curlin+1) );
X	    break;
Xcase 41:			/* abort */
X	    abort();
X	    break;
Xcase 42:			/* change characters */
X	    if ((succ = delnxt(lexcnt)))
X		succ = insert(1,TRUE);
X	    break;
Xcase 43:			/* jump back to last location */
X	    itmp = curlin;
X	    curlin = lastln;
X	    curchr = *(lines+curlin)+1;	/* point to the current character */
X	    verify(1);
X	    lastln = itmp;
X	    break;
Xcase 44:			/* tidy up screen */
X	    succ = neaten(lexcnt);
X	    break;
Xcase 45:			/* save current location */
X	    if (lexcnt < 1 || lexcnt > 9)
X		lexcnt = 0;
X	    noteloc[lexcnt] = curlin;
X	    break;
Xcase 46:			/* return to noted location */
X	    itmp = curlin;
X	    if (lexcnt < 1 || lexcnt > 9)
X		lexcnt = 0;
X	    if (noteloc[lexcnt] >= nxtlin)
X	      {
X		tverrb("Line no longer there ");
X		noteloc[lexcnt] = curlin;
X	      }
X	    else
X	      {
X		curlin = noteloc[lexcnt];
X		curchr = *(lines+curlin)+1; /* point to the current character */
X		verify(1);
X		lastln = itmp;
X	      }
X	    break;
X
Xcase 47:
X	    opsystem();		/* call operating system */
X	    break;
X
Xcase 48:
X	    if (lex_def)		/* default 1 passed */
X		lexcnt = rptuse + 1;	/* use current repeat loop */
X	    succ = edit_rpt(lexcnt);	/* edit repeat buffer */
X	    break;
X
Xcase 49:
X	    succ = store_rpt(lexcnt);	/* store repeat buffer */
X	    break;
X
Xcase 50:
X	    succ = exec_rpt(lexcnt);	/* execute repeat buffer */
X	    break;
X
Xcase 51:
X	    succ = ins_pat(lexcnt);
X	    break;
Xcase 52:
X	    succ = user_1(lexcnt);	/* user function 1 */
X	    break;
X
Xcase 53:
X	    succ = user_2(lexcnt);	/* user function 2 */
X	    break;
X	    }  			/* end of switch */
X	    continue;		/* next iteration of do loop */
X	  } /* end of else */
X      } /* end of do loop */
X    while (1);
X
Xlquit:
X    for ( wtpage(1) ; rdpage() ; wtpage(1) )	/* write whole file */
X	;
X    tvclr();
X  }
X
X/* =============================>>> EDIT_RPT <<<============================= */
X  edit_rpt(val)
X  int val;
X  {			/* copy repeat buffer val into buffer for editing */
X
X    SLOW char *cp;
X    SLOW int start_line;
X    
X    if (val == 0)
X	val = rptuse+1;
X
X    if (!chk_rpt_nr(val))
X        return FALSE;
X
X    --val;		/* change to relative */
X
X    beglin();		/* start by moving to beginning of current line */
X    start_line = curlin;	/* where we started */
X
X    
X    ins_chr('#'); ins_chr(val+'1'); ins_chr(':');
X	/* start with number */
X    ins_chr('<');	/* insert start of repeat loop */
X
X    for (cp = &rptbuf[val][0] ; *cp ; ++cp)
X	ins_chr(*cp);
X    ins_chr(27); ins_chr(27);	/* make a way for store_rpt to find end */
X
X    ins_chr(CR);		/* terminate line */
X    curlin = start_line;
X    curchr = *(lines+curlin)+1;
X    verify(1);
X    
X    return (TRUE);
X
X  }
X
X/* =============================>>> ENDLIN <<<============================= */
X  endlin()
X  { /* endlin - move cursor to end of the line */
X
X    FAST int cnt;
X    SLOW BUFFINDEX i;
X
X    cnt=0;
X    for (i=curchr; *(buff+i)!=ENDLINE; ++i)	/* find end of line */
X	++cnt;
X    right(cnt); 	/* move to end of line */
X  }
X
X/* =============================>>> EXEC_RPT <<<============================= */
X  exec_rpt(knt)
X  int knt;
X  {			/* this is combination of k:r,n& */
X    static char chr;
X    static int val;
X
X    if (! grptch(&chr))		/* get buffer # (k) to use */
X	return (FALSE);
X
X    val = chr - '0';		/* convert to 0 to 9 */
X
X    if (!chk_rpt_nr(val))
X        return FALSE;
X
X    if (val > 0)		/* change to specific buffer */
X	rptuse=val-1;	/* adjust for 0 index int */
X
X    if (knt != 1)
X	echof = FALSE;	/* turn off echo */
X
X    rptcnt[rptuse] = knt > 0 ? knt : (-knt);
X
X    return (TRUE);
X  }
X
X/* =============================>>> FINDDL <<<============================= */
X  finddl(ibeg,cnt)
X  int *ibeg,*cnt;
X  {  /* finddl - find the display line
X	known: current line, calculate where it would go on the screen */
X
X    if (curlin <= dsplin)
X      { 			/* it is in first part of the display */
X	*ibeg = 1;
X	*cnt = min(tvlins,nxtlin-1);
X	tvdlin = curlin;		/* update the display line */
X      }
X    else if (nxtlin-curlin <= tvlins-dsplin)	/* at bottom of display */
X      {
X	*ibeg = max(1,nxtlin-tvlins);
X	*cnt = min(tvlins,nxtlin-1);
X	tvdlin=min(curlin,tvlins-(nxtlin-curlin)+1);
X      }
X    else			/* normal case: in middle */
X      {
X	*ibeg=max(1,curlin-dsplin+1);
X	*cnt=min(tvlins,nxtlin-(*ibeg));
X	tvdlin=dsplin;
X      }
X }
X
X/* =============================>>> FINDX  <<<============================= */
X  int findx()
X  {  /* findx - find the x position of the current character
X		handles spacing for tabs, control characters etc */
X
X    SLOW BUFFINDEX i;
X    SLOW int pos,lmold;
X
X    pos = 0;
X    for (i = *(lines+curlin)+1; i<=curchr; ++i)
X	if (*(buff+i-1)<' ' && *(buff+i-1)>0)  /* cur pos depends on last chr */
X	    if (*(buff+i-1)==TAB)		/* handle tabs */
X		for (++pos ; ((pos-1) % 8)!=0; ++pos)
X		    ;
X	    else		/* control characters (echoed as ^X) */
X		pos += 2;	/* 2 spaces for other control character */
X	else			/* normal character */
X	    ++pos;
X
X    lmold = leftmg;		/* old left margin */
X    for (;;)
X      {
X	if (pos < leftmg)	/* won't fit on screen */
X	    leftmg -= 16;	/* shift left */
X	else if (pos >= tvcols+leftmg)
X	    leftmg += 16;
X	else
X	    break;
X      }
X
X    if (leftmg != lmold)		/* this handles screen shift */
X	newscr();
X
X    return (pos-leftmg+1);
X  }
X
X/* =============================>>> FIXEND  <<<============================= */
X  fixend()
X  { /* fixend - fix the error message line */
X
X    SLOW int lastl;
X
X    lastl = curlin+(tvlins-tvdlin);	/* the last line on the display */
X    tvxy(1,tvhardlines); 		/* get to last line */
X    tvelin();
X    if (lastl < nxtlin && tvlins == tvhardlines)  /* only if really there */
X	tvtype(lastl,1);		/* write it out */
X    if (curlin >= 1)
X	tvhdln();			/* restore cursor */
X    else
X	tvxy(1,1);
X   }
X
X/* =============================>>> GBGCOL <<<============================= */
X  int gbgcol()
X  { /* gbgcol - retrieve unused space in buff */
X
X    FAST int i;
X    SLOW int lastln;
X    SLOW BUFFINDEX nxtbad, nxtgud, to, from, whfrom, offset, newlin;
X
X    tverrb("Compacting buffer ");	/* let the user know, it might take a while */
X    offset = curchr - *(lines+curlin);	/* need to reset curchr later */
X
X    for (nxtbad=1 ; *(buff+nxtbad)!=GARBAGE && nxtbad < nxtchr; ++nxtbad)
X	    ;		/* find first space to free */
X    nxtgud=nxtbad;
X    lastln = 1; 	/* where to start search */
X    do
X      {
X	to=nxtbad;
X	for (from=nxtgud; *(buff+from)==GARBAGE && from<nxtchr; ++from)
X	    ;			/* find the next non-garbage character */
X
X/*  nxtbad pts to first junk character,
X    nxtgud pts to next possibly good character */
X
X	if (from >= nxtchr)
X	    break;		/* at the end of the buffer */
X	whfrom=from;		/* where it came from */
X	newlin = to;		/* remember start */
X	do
X	  {
X	    *(buff+to) = *(buff+from++);	/* copy good stuff up */
X	  }
X	while (*(buff+to++)!=ENDLINE);
X
X	nxtbad=to ; nxtgud=from;
X
X/*  now find the old line
X    following algorithm assumes next line is likely to
X    be near the previous line */
X
X	for (i=lastln ; i<nxtlin ; ++i)	/* start where last looked */
X	    if (*(lines+i)==whfrom)
X	      {
X		*(lines+i)=newlin;	/* point to new position */
X		if (curlin==i)
X		    curchr=newlin+offset;	/* fix curchr if need be */
X		break;
X	      }
X
X	if (i >= nxtlin)	/* not found in second half */
X	  {
X	    for (i=1 ; i < lastln ; ++i)
X		if (*(lines+i)==whfrom)
X		  {
X		    *(lines+i)=newlin;		/* point to new position */
X		    if (curlin==i)
X			curchr=newlin+offset;	/* fix curchr if need be */
X		    break;
X		  }
X	    if (i >= lastln)		/* make sure we really found it */
X	      {
X		tverrb("Compactor lost. Quit NOW! ");
X		for (i=1 ; i < 32000 ; ++i)
X		    ;
X		return (FALSE);
X	      }
X	  }
X	lastln = i;			/* start at next line down */
X      }
X    while (nxtgud < nxtchr);
X
X    for (to=nxtbad ; to<=nxtchr ; )
X	*(buff+to++)=GARBAGE;
X
X    nxtchr=nxtbad;			/* update the next free character */
X    tverr("Compactor done");
X    return (nxtsav-nxtchr >= 50);
X }
X
X/* =============================>>> GETSAV <<<============================= */
X  int getsav()
X  { /* ## getsav - get text from save buffer */
X
X    FAST int to,from;
X    SLOW BUFFINDEX fromch;
X    SLOW int newlin;
X
X    if (mxbuff-nxtsav+savlin >= nxtsav-nxtchr)	/* g.c. */
X	if (!gbgcol())
X	  {
X	    tverrb("No get room ");
X	    return (FALSE);
X	  }
X
X    if (nxtsav==mxbuff)		/* nothing to save */
X      {
X	return (TRUE);
X      }
X
X    if (mxbuff-nxtsav+savlin >= nxtsav-nxtchr || mxline-nxtlin <= savlin)
X      { 			/* room to get save buffer? */
X	tverrb("No get room ");
X	return (FALSE);		/* no room to save */
X      }
X
X/* check if in middle of line */
X    if (curchr > lines[curlin]+1)
X	ins_chr(CR);
X
X/*   # move down line to make space for new */
X    from=nxtlin-1;
X    nxtlin=nxtlin+savlin;
X    to=nxtlin-1;
X    while (from >= curlin)	/* copy line ptrs down right amnt. */
X	*(lines+(to--)) = *(lines+(from--));
X
X    newlin=curlin;		/* will insert new lines here */
X    curlin=to+1;
X    fromch = mxbuff;		/* where taking saved stuff from */
X    for ( ; newlin < curlin; ++newlin)
X      {
X	*(buff+nxtchr)=BEGLINE;	/* insert begline character */
X	*(lines+newlin) = nxtchr++; /* update line ptrs to new line */
X	do			/* copy stuff from save buffer */
X	  {
X	    *(buff+nxtchr++) = *(buff+fromch);
X	  }
X	while (*(buff+fromch--));
X      }
X    oldlen=0;
X    savlen=savlin;
X    newscr();
X    return (TRUE);
X  }
X
X/* =============================>>> GRPTCH <<<============================= */
X  int grptch(chr)
X  char *chr;
X  { /* grptch - gets a char from repeat buffer or gkbd */
X
X    SLOW char tmpchr;
X
X    if (rptcnt[rptuse]>0)	/* need to fetch from repeat buffer */
X	if (nxtrpt[rptuse] > lstrpt[rptuse])
X	  {
X	    return (FALSE);
X	  }
X	else
X	  {
X	    *chr=rptbuf[rptuse][nxtrpt[rptuse]];
X	    ++nxtrpt[rptuse];
X	  }
X    else
X      {
X	gkbd(&tmpchr);	/* read the character from the keyboard */
X	*chr=tmpchr;
X      }
X    return (TRUE);
X  }
X
X/* =============================>>> ins_pat  <<<============================= */
X  ins_pat(lexcnt)
X  int lexcnt;
X  {
X    SLOW char *chrp;
X
X    if (!*pat_buff)
X	return (FALSE);
X    for (chrp = pat_buff ; *chrp ; )	/* simply insert pattern buffer */
X      {
X	if (!ins_chr(*chrp++))	/* make sure it works */
X	    return (FALSE);
X      }
X
X    return (TRUE); 
X  }
X
X/* =============================>>> save_pat  <<<============================= */
X  save_pat()
X  {  /* save the find pattern, based on oldlen */
X
X    SLOW int i;
X    SLOW char *chrp;
X
X    
X    if (oldlen <= 0)
X      {
X	pat_buff[0] = 0;
X	return;				/* nothing to save */
X      }
X
X    for (i = 1 ; i <= oldlen ; ++i)	/* first, move left */
X      {
X	--curchr;
X	if (*(buff+curchr) == BEGLINE)
X	  {
X	    if (curlin > 1)
X	      {
X		--curlin;
X		for (curchr = *(lines+curlin) ; *(buff+curchr)!=ENDLINE ;
X		  ++curchr)
X		    ;		/* bump curchr to end of the line */
X	      }
X	    else
X	      {
X		++curchr;
X		break;
X	      }
X	  }
X      }
X
X     /* now save, go back right */
X
X    chrp = pat_buff;			/* put in pattern buffer */
X
X    for (i = 1 ; i <= oldlen ; ++i)
X      {
X	if (*(buff+curchr)==ENDLINE)
X	  {
X	    if (curlin+1 >= nxtlin)
X		break;		/* don't go beyond end! */
X	    ++curlin;
X	    curchr = *(lines+curlin)+1;
X	    *chrp++ = CR;	/* make a cr */
X	  }
X	else
X	  {
X	    if ((chrp - 100) < pat_buff)	/* make sure enough room */
X		*chrp++ = *(buff+curchr);
X	    ++curchr;
X	  }
X      }
X    *chrp = 0;					/* terminate */
X  }
X
X/* =============================>>> INSET <<<============================= */
X  inset(val,set)
X  int val,*set;
X  {
X     /* return true if val is in set set */
X
X    while (*set)
X	if (val == *set++)
X	    return TRUE;
X    return FALSE;
X  }
X
X/* =============================>>> ins_chr <<<============================= */
X  ins_chr(ival)
X  int ival;
X  {
X    return insert(ival,FALSE);		/* force insert */
X  }
X
X/* =============================>>> INSERT <<<============================= */
X  insert(ival,how)
X  int ival,how;
X  { /* insert - insert a character
X
X	if how is TRUE, then read characters from keyboard until
X	get an escape, otherwise insert ival */
X
X    SLOW BUFFINDEX from,to;
X    SLOW BUFFINDEX curbuf,curend;
X    SLOW int lenins, nocins, ityp, xf;
X    SLOW BUFFINDEX abvchr;
X
X    SLOW char chr;
X
X
X    static int ins_msg = TRUE;	/* own variable */
X
X    if (ins_msg)
X        csrins();		/* change cursor */
X
X    if (how)		/* how = 1 regular insert mode */
X      {
X	if (! grptch(&chr))	/* get char using grptch */
X	    goto l9999;
X	if (chr == ESC)		/* esc means done */
X	  {
X	    goto l1000;
X	  }
X      }
X    else
X	chr = ival;		/* use the passed value */
X
X    if (chr==ENDLINE || chr==BEGLINE || chr==GARBAGE || (chr==ENDFILE && usecz))
X	goto l9998;		/* don't allow this case! */
X
X    if (curlin < 1)
X      { 			/* buffer empty? */
X	curlin=1;		/* init for initial insert */
X	*(lines+1)=nxtchr;
X	curchr=nxtchr+1;
X	*(buff+nxtchr)=BEGLINE;
X	*(buff+nxtchr+1)=ENDLINE;
X	nxtchr += 2;
X	nxtlin = 2;
X      }
X
X    lenins=0;			/* remember length of insert for rmvlst */
X
X    do
X      {
X	if (nxtsav-nxtchr < ALMOSTOUT)
X	    if (!gbgcol())
X		goto l9999;	/* collect garbage if necessary */
X	curbuf = *(lines+curlin);  /* pick up the pointer to current line */
X	for (curend=curbuf; *(buff+curend)!=ENDLINE; ++curend)
X	    ;			/* get line length */
X	if (curend+1 < nxtchr)	/* not using last part of buffer */
X	  {
X	    if (curend-curbuf >= nxtsav-nxtchr)
X		goto l9998;	/* no more room! */
X	    curchr=nxtchr+(curchr-curbuf);	/* where curchr will be */
X	    *(lines+curlin)=nxtchr;	/* new line goes here */
X	    stcopy(buff,curbuf,buff,&nxtchr); /* copy the line to the end */
X	    curend=nxtchr++;	/* reset end pointer */
X	    kline(curbuf);	/* kill off the line */
X	    curbuf = *(lines+curlin);	/* update beginning pointer */
X	  }
X
X/*   #	to here, ready to insert the new character at the end of the line */
X
X	if (chr==' ' && wraplm > 1 && (tvx >= wraplm || leftmg > 1))	/* auto wrap? */
X	      chr = CR;
X#ifdef FILELF
X	if (chr == LF && how)
X	    ;			/* don't insert lfs in CR/LF systems, echo? */
X	else if (chr == CR)	/* inserting a new line */
X#else
X	if (chr == CR)		/* inserting a new line */
X#endif
X	  {
X	    if (nxtlin >= mxline)	/* any room? */
X	      {
X		tverrb("No more free lines for insert ");
X		goto l9999;
X	      }
X
X	    for (from=curend; from >= curchr; --from)
X		*(buff+from+2) = *(buff+from);		/* copy chars down */
X	    nxtchr += 2;	/* bump nxtchr to free space */
X
X	    *(buff+curchr) = ENDLINE;	/* mark as endline */
X	    *(buff+curchr+1) = BEGLINE;	/* beginning of line */
X	    ++lenins;
X
X	    to=nxtlin;		/* move lines down */
X	    for (from = nxtlin-1; from > curlin; )
X	      { 		/* bump the lines down */
X		*(lines+to--) = *(lines+from--);
X	      }
X	    ++nxtlin;	/* bump to next free line */
X
X	    *(lines+curlin+1)=curchr+1;		/* remember where */
X
X	    if (ins_msg)
X	        fixend();				/* fix last line */
X	    tvelin();	/* erase stuff after cr */
X
X	    nocins = (leftmg > 1);	/* ciline no good if left marg > 1 */
X
X	    dwnlin(1);	/* go down one line */
X
X	    if (ciline[0] == 0 || nocins)
X	      {
X		tvescr();		/* erase the rest of the screen */
X		ityp = min(tvlins-tvdlin+1,nxtlin-curlin);
X	      }
X	    else
X	      {
X		tvinsl(); 	/* insert a line */
X		ityp = 1;
X	      }
X
X	    tvtype(curlin,ityp);
X	    tvhdln();
X	    if (ins_msg)
X		csrins();			/* change cursor */
X
X	    if (autoin && curlin > 2)		/* automatic indentation! */
X	      {
X		ins_msg = FALSE;		/* turn off insert message */
X		abvchr = *(lines+curlin-1)+1;	/* prevous line */
X		while (*(buff+abvchr)==' ' || *(buff+abvchr)==TAB)
X		    if (!insert(*(buff+abvchr++),FALSE) )
X		      {
X			ins_msg = TRUE;
X			goto l9999;
X		      }
X		    else if (ttymode)		/* hmm, now what? */
X		      {
X			ttymode = FALSE;
X			ttwt(*(buff+abvchr-1));
X			ttymode = TRUE;
X		      }
X		ins_msg = TRUE;
X		fixend();
X		csrins();			/* change cursor */
X	      }
X	  }
X	else if (chr == delkey && how)
X	  {
X	    if (!delnxt(-1))	/* rubbing out last character */
X		goto l9999;
X	    --lenins;
X	  }
X	else			/* inserting on the current line */
X	  {
X	    to = nxtchr;		/* will move to nxtchr */
X	    for (from = curend ; from >= curchr; )
X	      {
X		*(buff+to--) = *(buff+from--);
X	      }
X	    curend=nxtchr++;	/* end is now at curchr, bump nxtchr */
X	    *(buff+curchr)=chr;	/* stick in the current character */
X	    ++lenins;
X	    if (tvlins < tvhardlines - 10)
X	      {
X		tvelin();
X		ctrlch(chr);
X		ctrlch('+');
X	      }
X	    else
X	        tvtyln(curchr);	/* retype rest of the line */
X	    ++curchr;		/* reset the curchr pointer */
X	    xf = findx();
X	    tvxy(xf,tvy);	/* reset the cursor */
X	  }
X
X/* the character has been inserted and displayed, get another maybe */
X
X	if (how)
X	    if (!grptch(&chr))
X		goto l9999;
X      }
X    while (how && chr != ESC);	/* end of do */
X
X    if (tvlins < tvhardlines - 10)		/* fix for slow baud */
X      {
X	tvelin();
X        tvtyln(curchr);	/* retype rest of the line */
X	xf = findx();
X	tvxy(xf,tvy);	/* reset the cursor */
X      }
X
X    oldlen = lenins;
X    savlen = (-1);		/* haven't saved lines */
X    goto l1000;
X
Xl9998:
X    tverrb("Can't insert that char ");
Xl9999:
X    csrcmd();
X    return FALSE;
Xl1000:
X
X    if (ins_msg)
X        fixend();
X    csrcmd();
X    return TRUE;
X }
X/* ------------------------ tvx_1.c ------------------------------------- */
SHAR_EOF
echo ALL DONE!
exit 0