/* Copyright (c) 1981 Regents of the University of California */
static char *sccsid = "@(#)ex_subr.c	7.2	7/26/81";
#include "ex.h"
#include "ex_re.h"
#include "ex_tty.h"
#include "ex_vis.h"

/*
 * Random routines, in alphabetical order.
 */

any(c, s)
	int c;
	register char *s;
{
	register int x;

	while (x = *s++)
		if (x == c)
			return (1);
	return (0);
}

backtab(i)
	register int i;
{
	register int j;

	j = i % value(SHIFTWIDTH);
	if (j == 0)
		j = value(SHIFTWIDTH);
	i -= j;
	if (i < 0)
		i = 0;
	return (i);
}

change()
{

	tchng++;
	chng = tchng;
}

/*
 * Column returns the number of
 * columns occupied by printing the
 * characters through position cp of the
 * current line.
 */
column(cp)
	register char *cp;
{

	if (cp == 0)
		cp = &linebuf[LBSIZE - 2];
	return (qcolumn(cp, (char *) 0));
}

/*
 * Ignore a comment to the end of the line.
 * This routine eats the trailing newline so don't call newline().
 */
comment()
{
	register int c;

	do {
		c = getchar();
	} while (c != '\n' && c != EOF);
	if (c == EOF)
		ungetchar(c);
}

Copy(to, from, size)
	register char *from, *to;
	register int size;
{

	if (size > 0)
		do
			*to++ = *from++;
		while (--size > 0);
}

copyw(to, from, size)
	register line *from, *to;
	register int size;
{

	if (size > 0)
		do
			*to++ = *from++;
		while (--size > 0);
}

copywR(to, from, size)
	register line *from, *to;
	register int size;
{

	while (--size >= 0)
		to[size] = from[size];
}

ctlof(c)
	int c;
{

	return (c == TRIM ? '?' : c | ('A' - 1));
}

dingdong()
{

	if (VB)
		putpad(VB);
	else if (value(ERRORBELLS))
		putch('\207');
}

fixindent(indent)
	int indent;
{
	register int i;
	register char *cp;

	i = whitecnt(genbuf);
	cp = vpastwh(genbuf);
	if (*cp == 0 && i == indent && linebuf[0] == 0) {
		genbuf[0] = 0;
		return (i);
	}
	CP(genindent(i), cp);
	return (i);
}

filioerr(cp)
	char *cp;
{
	register int oerrno = errno;

	lprintf("\"%s\"", cp);
	errno = oerrno;
	syserror();
}

char *
genindent(indent)
	register int indent;
{
	register char *cp;

	for (cp = genbuf; indent >= value(TABSTOP); indent -= value(TABSTOP))
		*cp++ = '\t';
	for (; indent > 0; indent--)
		*cp++ = ' ';
	return (cp);
}

getDOT()
{

	getline(*dot);
}

line *
getmark(c)
	register int c;
{
	register line *addr;
	
	for (addr = one; addr <= dol; addr++)
		if (names[c - 'a'] == (*addr &~ 01)) {
			return (addr);
		}
	return (0);
}

getn(cp)
	register char *cp;
{
	register int i = 0;

	while (isdigit(*cp))
		i = i * 10 + *cp++ - '0';
	if (*cp)
		return (0);
	return (i);
}

ignnEOF()
{
	register int c = getchar();

	if (c == EOF)
		ungetchar(c);
	else if (c=='"')
		comment();
}

iswhite(c)
	int c;
{

	return (c == ' ' || c == '\t');
}

junk(c)
	register int c;
{

	if (c && !value(BEAUTIFY))
		return (0);
	if (c >= ' ' && c != TRIM)
		return (0);
	switch (c) {

	case '\t':
	case '\n':
	case '\f':
		return (0);

	default:
		return (1);
	}
}

killed()
{

	killcnt(addr2 - addr1 + 1);
}

killcnt(cnt)
	register int cnt;
{

	if (inopen) {
		notecnt = cnt;
		notenam = notesgn = "";
		return;
	}
	if (!notable(cnt))
		return;
	printf("%d lines", cnt);
	if (value(TERSE) == 0) {
		printf(" %c%s", Command[0] | ' ', Command + 1);
		if (Command[strlen(Command) - 1] != 'e')
			putchar('e');
		putchar('d');
	}
	putNFL();
}

lineno(a)
	line *a;
{

	return (a - zero);
}

lineDOL()
{

	return (lineno(dol));
}

lineDOT()
{

	return (lineno(dot));
}

markDOT()
{

	markpr(dot);
}

markpr(which)
	line *which;
{

	if ((inglobal == 0 || inopen) && which <= endcore) {
		names['z'-'a'+1] = *which & ~01;
		if (inopen)
			ncols['z'-'a'+1] = cursor;
	}
}

markreg(c)
	register int c;
{

	if (c == '\'' || c == '`')
		return ('z' + 1);
	if (c >= 'a' && c <= 'z')
		return (c);
	return (0);
}

/*
 * Mesg decodes the terse/verbose strings. Thus
 *	'xxx@yyy' -> 'xxx' if terse, else 'xxx yyy'
 *	'xxx|yyy' -> 'xxx' if terse, else 'yyy'
 * All others map to themselves.
 */
char *
mesg(str)
	register char *str;
{
	register char *cp;

	str = strcpy(genbuf, str);
	for (cp = str; *cp; cp++)
		switch (*cp) {

		case '@':
			if (value(TERSE))
				*cp = 0;
			else
				*cp = ' ';
			break;

		case '|':
			if (value(TERSE) == 0)
				return (cp + 1);
			*cp = 0;
			break;
		}
	return (str);
}

/*VARARGS2*/
merror(seekpt, i)
#ifdef VMUNIX
	char *seekpt;
#else
# ifdef lint
	char *seekpt;
# else
	int seekpt;
# endif
#endif
	int i;
{
	register char *cp = linebuf;

	if (seekpt == 0)
		return;
	merror1(seekpt);
	if (*cp == '\n')
		putnl(), cp++;
	if (inopen > 0 && CE)
		vclreol();
	if (SO && SE)
		putpad(SO);
	printf(mesg(cp), i);
	if (SO && SE)
		putpad(SE);
}

merror1(seekpt)
#ifdef VMUNIX
	char *seekpt;
#else
# ifdef lint
	char *seekpt;
# else
	int seekpt;
# endif
#endif
{

#ifdef VMUNIX
	strcpy(linebuf, seekpt);
#else
	lseek(erfile, (long) seekpt, 0);
	if (read(erfile, linebuf, 128) < 2)
		CP(linebuf, "ERROR");
#endif
}

morelines()
{
#ifdef	pdp11
#define	MAXDATA	(56*1024)
	register char *end;

	if ((int) sbrk(1024 * sizeof (line)) != -1) {
		endcore += 1024;
	} else {
		if (endcore >= MAXDATA)
			return(-1);
		end = MAXDATA;
		/*
		 * Ask for end+2 since we want end to be last used location.
		 */
		while (brk(end+2) == -1)
			end -= 64;
		if (end <= (char *)endcore)
			return(-1);
		endcore = (line *) end;
	}
	return(0);
#else
	if ((int) sbrk(1024 * sizeof (line)) == -1)
		return (-1);
	endcore += 1024;
	return (0);
#endif
}

nonzero()
{

	if (addr1 == zero) {
		notempty();
		error("Nonzero address required@on this command");
	}
}

notable(i)
	int i;
{

	return (hush == 0 && !inglobal && i > value(REPORT));
}


notempty()
{

	if (dol == zero)
		error("No lines@in the buffer");
}


netchHAD(cnt)
	int cnt;
{

	netchange(lineDOL() - cnt);
}

netchange(i)
	register int i;
{
	register char *cp;

	if (i > 0)
		notesgn = cp = "more ";
	else
		notesgn = cp = "fewer ", i = -i;
	if (inopen) {
		notecnt = i;
		notenam = "";
		return;
	}
	if (!notable(i))
		return;
	printf(mesg("%d %slines@in file after %s"), i, cp, Command);
	putNFL();
}

putmark(addr)
	line *addr;
{

	putmk1(addr, putline());
}

putmk1(addr, n)
	register line *addr;
	int n;
{
	register line *markp;
	register oldglobmk;

	oldglobmk = *addr & 1;
	*addr &= ~1;
	for (markp = (anymarks ? names : &names['z'-'a'+1]);
	  markp <= &names['z'-'a'+1]; markp++)
		if (*markp == *addr)
			*markp = n;
	*addr = n | oldglobmk;
}

char *
plural(i)
	long i;
{

	return (i == 1 ? "" : "s");
}

int	qcount();
short	vcntcol;

qcolumn(lim, gp)
	register char *lim, *gp;
{
	register int x;
	int (*OO)();

	OO = Outchar;
	Outchar = qcount;
	vcntcol = 0;
	if (lim != NULL)
		x = lim[1], lim[1] = 0;
	pline(0);
	if (lim != NULL)
		lim[1] = x;
	if (gp)
		while (*gp)
			putchar(*gp++);
	Outchar = OO;
	return (vcntcol);
}

int
qcount(c)
	int c;
{

	if (c == '\t') {
		vcntcol += value(TABSTOP) - vcntcol % value(TABSTOP);
		return;
	}
	vcntcol++;
}

reverse(a1, a2)
	register line *a1, *a2;
{
	register line t;

	for (;;) {
		t = *--a2;
		if (a2 <= a1)
			return;
		*a2 = *a1;
		*a1++ = t;
	}
}

save(a1, a2)
	line *a1;
	register line *a2;
{
	register int more;

	if (!FIXUNDO)
		return;
#ifdef TRACE
	if (trace)
		vudump("before save");
#endif
	undkind = UNDNONE;
	undadot = dot;
	more = (a2 - a1 + 1) - (unddol - dol);
	while (more > (endcore - truedol))
		if (morelines() < 0)
			error("Out of memory@saving lines for undo - try using ed");
	if (more)
		(*(more > 0 ? copywR : copyw))(unddol + more + 1, unddol + 1,
		    (truedol - unddol));
	unddol += more;
	truedol += more;
	copyw(dol + 1, a1, a2 - a1 + 1);
	undkind = UNDALL;
	unddel = a1 - 1;
	undap1 = a1;
	undap2 = a2 + 1;
#ifdef TRACE
	if (trace)
		vudump("after save");
#endif
}

save12()
{

	save(addr1, addr2);
}

saveall()
{

	save(one, dol);
}

span()
{

	return (addr2 - addr1 + 1);
}

sync()
{

	chng = 0;
	tchng = 0;
	xchng = 0;
}


skipwh()
{
	register int wh;

	wh = 0;
	while (iswhite(peekchar())) {
		wh++;
		ignchar();
	}
	return (wh);
}

/*VARARGS2*/
smerror(seekpt, cp)
#ifdef lint
	char *seekpt;
#else
	int seekpt;
#endif
	char *cp;
{

	if (seekpt == 0)
		return;
	merror1(seekpt);
	if (inopen && CE)
		vclreol();
	if (SO && SE)
		putpad(SO);
	lprintf(mesg(linebuf), cp);
	if (SO && SE)
		putpad(SE);
}

#define	std_nerrs (sizeof std_errlist / sizeof std_errlist[0])

#define	error(i)	i

#ifdef lint
char	*std_errlist[] = {
#else
# ifdef VMUNIX
char	*std_errlist[] = {
# else
short	std_errlist[] = {
# endif
#endif
	error("Error 0"),
	error("Not super-user"),
	error("No such file or directory"),
	error("No such process"),
	error("Interrupted system call"),
	error("Physical I/O error"),
	error("No such device or address"),
	error("Argument list too long"),
	error("Exec format error"),
	error("Bad file number"),
	error("No children"),
	error("No more processes"),
	error("Not enough core"),
	error("Permission denied"),
	error("Bad address"),
	error("Block device required"),
	error("Mount device busy"),
	error("File exists"),
	error("Cross-device link"),
	error("No such device"),
	error("Not a directory"),
	error("Is a directory"),
	error("Invalid argument"),
	error("File table overflow"),
	error("Too many open files"),
	error("Not a typewriter"),
	error("Text file busy"),
	error("File too large"),
	error("No space left on device"),
	error("Illegal seek"),
	error("Read-only file system"),
	error("Too many links"),
	error("Broken pipe"),
#ifndef V6
	error("Math argument"),
	error("Result too large"),
#endif
	error("Quota exceeded")		/* Berkeley quota systems only */
};

#undef	error

char *
strend(cp)
	register char *cp;
{

	while (*cp)
		cp++;
	return (cp);
}

strcLIN(dp)
	char *dp;
{

	CP(linebuf, dp);
}

syserror()
{
	register int e = errno;

	dirtcnt = 0;
	putchar(' ');
	edited = 0;	/* for temp file errors, for example */
	if (e >= 0 && errno <= std_nerrs)
		error(std_errlist[e]);
	else
		error("System error %d", e);
}

/*
 * Return the column number that results from being in column col and
 * hitting a tab, where tabs are set every ts columns.  Work right for
 * the case where col > COLUMNS, even if ts does not divide COLUMNS.
 */
tabcol(col, ts)
int col, ts;
{
	int offset, result;

	if (col >= COLUMNS) {
		offset = COLUMNS * (col/COLUMNS);
		col -= offset;
	} else
		offset = 0;
	result = col + ts - (col % ts) + offset;
	return (result);
}

char *
vfindcol(i)
	int i;
{
	register char *cp;
	register int (*OO)() = Outchar;

	Outchar = qcount;
	ignore(qcolumn(linebuf - 1, NOSTR));
	for (cp = linebuf; *cp && vcntcol < i; cp++)
		putchar(*cp);
	if (cp != linebuf)
		cp--;
	Outchar = OO;
	return (cp);
}

char *
vskipwh(cp)
	register char *cp;
{

	while (iswhite(*cp) && cp[1])
		cp++;
	return (cp);
}


char *
vpastwh(cp)
	register char *cp;
{

	while (iswhite(*cp))
		cp++;
	return (cp);
}

whitecnt(cp)
	register char *cp;
{
	register int i;

	i = 0;
	for (;;)
		switch (*cp++) {

		case '\t':
			i += value(TABSTOP) - i % value(TABSTOP);
			break;

		case ' ':
			i++;
			break;

		default:
			return (i);
		}
}

#ifdef lint
Ignore(a)
	char *a;
{

	a = a;
}

Ignorf(a)
	int (*a)();
{

	a = a;
}
#endif

markit(addr)
	line *addr;
{

	if (addr != dot && addr >= one && addr <= dol)
		markDOT();
}

/*
 * The following code is defensive programming against a bug in the
 * pdp-11 overlay implementation.  Sometimes it goes nuts and asks
 * for an overlay with some garbage number, which generates an emt
 * trap.  This is a less than elegant solution, but it is somewhat
 * better than core dumping and losing your work, leaving your tty
 * in a weird state, etc.
 */
int _ovno;
onemt()
{
	int oovno;

	signal(SIGEMT, onemt);
	oovno = _ovno;
	/* 2 and 3 are valid on 11/40 type vi, so */
	if (_ovno < 0 || _ovno > 3)
		_ovno = 0;
	error("emt trap, _ovno is %d @ - try again");
}

/*
 * When a hangup occurs our actions are similar to a preserve
 * command.  If the buffer has not been [Modified], then we do
 * nothing but remove the temporary files and exit.
 * Otherwise, we sync the temp file and then attempt a preserve.
 * If the preserve succeeds, we unlink our temp files.
 * If the preserve fails, we leave the temp files as they are
 * as they are a backup even without preservation if they
 * are not removed.
 */
onhup()
{

	/*
	 * USG tty driver can send multiple HUP's!!
	 */
	signal(SIGINT, SIG_IGN);
	signal(SIGHUP, SIG_IGN);
	if (chng == 0) {
		cleanup(1);
		exit(0);
	}
	if (setexit() == 0) {
		if (preserve()) {
			cleanup(1);
			exit(0);
		}
	}
	exit(1);
}

/*
 * An interrupt occurred.  Drain any output which
 * is still in the output buffering pipeline.
 * Catch interrupts again.  Unless we are in visual
 * reset the output state (out of -nl mode, e.g).
 * Then like a normal error (with the \n before Interrupt
 * suppressed in visual mode).
 */
onintr()
{

#ifndef CBREAK
	signal(SIGINT, onintr);
#else
	signal(SIGINT, inopen ? vintr : onintr);
#endif
	alarm(0);	/* in case we were called from map */
	draino();
	if (!inopen) {
		pstop();
		setlastchar('\n');
#ifdef CBREAK
	}
#else
	} else
		vraw();
#endif
	error("\nInterrupt" + inopen);
}

/*
 * If we are interruptible, enable interrupts again.
 * In some critical sections we turn interrupts off,
 * but not very often.
 */
setrupt()
{

	if (ruptible) {
#ifndef CBREAK
		signal(SIGINT, onintr);
#else
		signal(SIGINT, inopen ? vintr : onintr);
#endif
#ifdef SIGTSTP
		if (dosusp)
			signal(SIGTSTP, onsusp);
#endif
	}
}

preserve()
{

#ifdef VMUNIX
	tflush();
#endif
	synctmp();
	pid = fork();
	if (pid < 0)
		return (0);
	if (pid == 0) {
		close(0);
		dup(tfile);
		execl(EXPRESERVE, "expreserve", (char *) 0);
		exit(1);
	}
	waitfor();
	if (rpid == pid && status == 0)
		return (1);
	return (0);
}

#ifndef V6
exit(i)
	int i;
{

# ifdef TRACE
	if (trace)
		fclose(trace);
# endif
	_exit(i);
}
#endif

#ifdef SIGTSTP
/*
 * We have just gotten a susp.  Suspend and prepare to resume.
 */
onsusp()
{
	ttymode f;

	f = setty(normf);
	vnfl();
	putpad(TE);
	flush();

	signal(SIGTSTP, SIG_DFL);
	kill(0, SIGTSTP);

	/* the pc stops here */

	signal(SIGTSTP, onsusp);
	vcontin(0);
	setty(f);
	if (!inopen)
		error(0);
	else {
		if (vcnt < 0) {
			vcnt = -vcnt;
			if (state == VISUAL)
				vclear();
			else if (state == CRTOPEN)
				vcnt = 0;
		}
		vdirty(0, LINES);
		vrepaint(cursor);
	}
}