Import sources from 2011-03-30 iso image

1 files changed, 880 insertions, 0 deletions

diff --git a/sys/src/cmd/abaco/text.c b/sys/src/cmd/abaco/text.c
new file mode 100755
index 000000000..8c145a154
--- /dev/null
+++ b/sys/src/cmd/abaco/text.c
@@ -0,0 +1,880 @@
+#include <u.h>
+#include <libc.h>
+#include <draw.h>
+#include <memdraw.h>
+#include <thread.h>
+#include <cursor.h>
+#include <mouse.h>
+#include <keyboard.h>
+#include <frame.h>
+#include <plumb.h>
+#include <html.h>
+#include "dat.h"
+#include "fns.h"
+
+Image	*tagcols[NCOL];
+Image	*textcols[NCOL];
+
+
+void
+textinit(Text *t, Image *b, Rectangle r, Font *f, Image *cols[NCOL])
+{
+	t->all = r;
+	t->scrollr = r;
+	t->scrollr.max.x = r.min.x+Scrollsize;
+	t->lastsr = ZR;
+	r.min.x += Scrollsize+Scrollgap;
+	t->rs.nr = 0;
+	memmove(t->Frame.cols, cols, sizeof t->Frame.cols);
+	textredraw(t, r, f, b);
+}
+
+void
+textredraw(Text *t, Rectangle r, Font *f, Image *b)
+{
+	Rectangle r1;
+
+	frinit(t, r, f, b, t->Frame.cols);
+	r1 = t->r;
+	r1.min.x -= Scrollsize+Scrollgap;	/* back fill to scroll bar */
+	draw(t->b, r1, t->cols[BACK], nil, ZP);
+	t->maxtab = Maxtab*stringwidth(f, "0");
+	textfill(t);
+	textsetselect(t, t->q0, t->q1);
+}
+
+int
+textresize(Text *t, Image *b, Rectangle r)
+{
+	if(Dy(r) > 0)
+		r.max.y -= Dy(r)%t->font->height;
+	else
+		r.max.y = r.min.y;
+
+	t->all = r;
+	t->scrollr = r;
+	t->scrollr.max.x = r.min.x+Scrollsize;
+	t->lastsr = ZR;
+	r.min.x += Scrollsize+Scrollgap;
+	frclear(t, 0);
+	textredraw(t, r, t->font, b);
+	if(t->what == Textarea)
+		textscrdraw(t);
+	return r.max.y;
+}
+
+void
+textclose(Text *t)
+{
+	closerunestr(&t->rs);
+	frclear(t, 1);
+}
+
+void
+textinsert(Text *t, uint q0, Rune *r, uint n)
+{
+	if(n == 0)
+		return;
+
+	t->rs.r = runerealloc(t->rs.r, t->rs.nr+n);
+	runemove(t->rs.r+q0+n, t->rs.r+q0, t->rs.nr-q0);
+	runemove(t->rs.r+q0, r, n);
+	t->rs.nr += n;
+	if(q0 < t->q1)
+		t->q1 += n;
+	if(q0 < t->q0)
+		t->q0 += n;
+	if(q0 < t->org)
+		t->org += n;
+	else if(q0 <= t->org+t->nchars)
+		frinsert(t, r, r+n, q0-t->org);
+}
+
+void
+textfill(Text *t)
+{
+	Rune *rp;
+	int i, n, m, nl;
+
+	if(t->lastlinefull)
+		return;
+	rp = runemalloc(BUFSIZE*8);
+	do{
+		n = t->rs.nr-(t->org+t->nchars);
+		if(n == 0)
+			break;
+		if(n > 2000)	/* educated guess at reasonable amount */
+			n = 2000;
+		runemove(rp, t->rs.r+(t->org+t->nchars), n);
+		/*
+		 * it's expensive to frinsert more than we need, so
+		 * count newlines.
+		 */
+		nl = t->maxlines-t->nlines;
+		m = 0;
+		for(i=0; i<n; ){
+			if(rp[i++] == '\n'){
+				m++;
+				if(m >= nl)
+					break;
+			}
+		}
+		frinsert(t, rp, rp+i, t->nchars);
+	}while(t->lastlinefull == FALSE);
+	free(rp);
+}
+
+void
+textdelete(Text *t, uint q0, uint q1)
+{
+	uint n, p0, p1;
+
+	n = q1-q0;
+	if(n == 0)
+		return;
+
+	runemove(t->rs.r+q0, t->rs.r+q1, t->rs.nr-q1);
+	t->rs.nr -= n;
+	if(q0 < t->q0)
+		t->q0 -= min(n, t->q0-q0);
+	if(q0 < t->q1)
+		t->q1 -= min(n, t->q1-q0);
+	if(q1 <= t->org)
+		t->org -= n;
+	else if(q0 < t->org+t->nchars){
+		p1 = q1 - t->org;
+		if(p1 > t->nchars)
+			p1 = t->nchars;
+		if(q0 < t->org){
+			t->org = q0;
+			p0 = 0;
+		}else
+			p0 = q0 - t->org;
+		frdelete(t, p0, p1);
+		textfill(t);
+	}
+	t->rs.r[t->rs.nr] = L'\0';
+}
+
+int
+textbswidth(Text *t, Rune c)
+{
+	uint q, eq;
+	Rune r;
+	int skipping;
+
+	/* there is known to be at least one character to erase */
+	if(c == 0x08)	/* ^H: erase character */
+		return 1;
+	q = t->q0;
+	skipping = TRUE;
+	while(q > 0){
+		r = t->rs.r[q-1];
+		if(r == '\n'){		/* eat at most one more character */
+			if(q == t->q0)	/* eat the newline */
+				--q;
+			break;
+		}
+		if(c == 0x17){
+			eq = isalnum(r);
+			if(eq && skipping)	/* found one; stop skipping */
+				skipping = FALSE;
+			else if(!eq && !skipping)
+				break;
+		}
+		--q;
+	}
+	return t->q0-q;
+}
+
+void
+texttype(Text *t, Rune r)
+{
+	uint q0, q1;
+	int nb, n;
+	int nr;
+	Rune *rp;
+
+	if(t->what!=Textarea && r=='\n'){
+		if(t->what==Urltag)
+			get(t, t, XXX, XXX, nil, 0);
+		return;
+	}
+	if(t->what==Tag && (r==Kscrollonedown || r==Kscrolloneup))
+		return;
+
+	nr = 1;
+	rp = &r;
+	switch(r){
+	case Kleft:
+		if(t->q0 > 0)
+			textshow(t, t->q0-1, t->q0-1, TRUE);
+		return;
+	case Kright:
+		if(t->q1 < t->rs.nr)
+			textshow(t, t->q1+1, t->q1+1, TRUE);
+		return;
+	case Kdown:
+		n = t->maxlines/3;
+		goto case_Down;
+	case Kscrollonedown:
+		n = mousescrollsize(t->maxlines);
+		if(n <= 0)
+			n = 1;
+		goto case_Down;
+	case Kpgdown:
+		n = 2*t->maxlines/3;
+	case_Down:
+		q0 = t->org+frcharofpt(t, Pt(t->r.min.x, t->r.min.y+n*t->font->height));
+		textsetorigin(t, q0, TRUE);
+		return;
+	case Kup:
+		n = t->maxlines/3;
+		goto case_Up;
+	case Kscrolloneup:
+		n = mousescrollsize(t->maxlines);
+		goto case_Up;
+	case Kpgup:
+		n = 2*t->maxlines/3;
+	case_Up:
+		q0 = textbacknl(t, t->org, n);
+		textsetorigin(t, q0, TRUE);
+		return;
+	case Khome:
+		textshow(t, 0, 0, FALSE);
+		return;
+	case Kend:
+		textshow(t, t->rs.nr, t->rs.nr, FALSE);
+		return;
+	case 0x01:	/* ^A: beginning of line */
+		/* go to where ^U would erase, if not already at BOL */
+		nb = 0;
+		if(t->q0>0 && t->rs.r[t->q0-1]!='\n')
+			nb = textbswidth(t, 0x15);
+		textshow(t, t->q0-nb, t->q0-nb, TRUE);
+		return;
+	case 0x05:	/* ^E: end of line */
+		q0 = t->q0;
+		while(q0<t->rs.nr && t->rs.r[q0]!='\n')
+			q0++;
+		textshow(t, q0, q0, TRUE);
+		return;
+	}
+	if(t->q1 > t->q0)
+		cut(t, t, TRUE, TRUE, nil, 0);
+
+	textshow(t, t->q0, t->q0, TRUE);
+	switch(r){
+	case 0x08:	/* ^H: erase character */
+	case 0x15:	/* ^U: erase line */
+	case 0x17:	/* ^W: erase word */
+		if(t->q0 == 0)	/* nothing to erase */
+			return;
+		nb = textbswidth(t, r);
+		q1 = t->q0;
+		q0 = q1-nb;
+		/* if selection is at beginning of window, avoid deleting invisible text */
+		if(q0 < t->org){
+			q0 = t->org;
+			nb = q1-q0;
+		}
+		if(nb > 0){
+			textdelete(t, q0, q0+nb);
+			textsetselect(t, q0, q0);
+		}
+		return;
+	}
+	/* otherwise ordinary character; just insert */
+	textinsert(t, t->q0, &r, 1);
+	if(rp != &r)
+		free(rp);
+	textsetselect(t, t->q0+nr, t->q0+nr);
+	if(t->what == Textarea)
+		textscrdraw(t);
+}
+
+static	Text	*clicktext;
+static	uint	clickmsec;
+static	Text	*selecttext;
+static	uint	selectq;
+
+/*
+ * called from frame library
+ */
+void
+framescroll(Frame *f, int dl)
+{
+	if(f != &selecttext->Frame)
+		error("frameselect not right frame");
+	textframescroll(selecttext, dl);
+}
+
+void
+textframescroll(Text *t, int dl)
+{
+	uint q0;
+
+	if(dl == 0){
+		scrsleep(100);
+		return;
+	}
+	if(dl < 0){
+		q0 = textbacknl(t, t->org, -dl);
+		if(selectq > t->org+t->p0)
+			textsetselect(t, t->org+t->p0, selectq);
+		else
+			textsetselect(t, selectq, t->org+t->p0);
+	}else{
+		if(t->org+t->nchars == t->rs.nr)
+			return;
+		q0 = t->org+frcharofpt(t, Pt(t->r.min.x, t->r.min.y+dl*t->font->height));
+		if(selectq > t->org+t->p1)
+			textsetselect(t, t->org+t->p1, selectq);
+		else
+			textsetselect(t, selectq, t->org+t->p1);
+	}
+	textsetorigin(t, q0, TRUE);
+}
+
+void
+textselect(Text *t)
+{
+	uint q0, q1;
+	int b, x, y;
+	int state;
+
+	selecttext = t;
+	/*
+	 * To have double-clicking and chording, we double-click
+	 * immediately if it might make sense.
+	 */
+	b = mouse->buttons;
+	q0 = t->q0;
+	q1 = t->q1;
+	selectq = t->org+frcharofpt(t, mouse->xy);
+	if(clicktext==t && mouse->msec-clickmsec<500)
+	if(q0==q1 && selectq==q0){
+		textdoubleclick(t, &q0, &q1);
+		textsetselect(t, q0, q1);
+		flushimage(display, 1);
+		x = mouse->xy.x;
+		y = mouse->xy.y;
+		/* stay here until something interesting happens */
+		do
+			readmouse(mousectl);
+		while(mouse->buttons==b && abs(mouse->xy.x-x)<3 && abs(mouse->xy.y-y)<3);
+		mouse->xy.x = x;	/* in case we're calling frselect */
+		mouse->xy.y = y;
+		q0 = t->q0;	/* may have changed */
+		q1 = t->q1;
+		selectq = q0;
+	}
+	if(mouse->buttons == b){
+		t->Frame.scroll = framescroll;
+		frselect(t, mousectl);
+		/* horrible botch: while asleep, may have lost selection altogether */
+		if(selectq > t->rs.nr)
+			selectq = t->org + t->p0;
+		t->Frame.scroll = nil;
+		if(selectq < t->org)
+			q0 = selectq;
+		else
+			q0 = t->org + t->p0;
+		if(selectq > t->org+t->nchars)
+			q1 = selectq;
+		else
+			q1 = t->org+t->p1;
+	}
+	if(q0 == q1){
+		if(q0==t->q0 && clicktext==t && mouse->msec-clickmsec<500){
+			textdoubleclick(t, &q0, &q1);
+			clicktext = nil;
+		}else{
+			clicktext = t;
+			clickmsec = mouse->msec;
+		}
+	}else
+		clicktext = nil;
+	textsetselect(t, q0, q1);
+	flushimage(display, 1);
+	state = 0;	/* undo when possible; +1 for cut, -1 for paste */
+	while(mouse->buttons){
+		mouse->msec = 0;
+		b = mouse->buttons;
+		if((b&1) && (b&6)){
+			if(b & 2){
+				if(state==-1 && t->what==Textarea){
+					textsetselect(t, q0, t->q0);
+					state = 0;
+				}else if(state != 1){
+					cut(t, t, TRUE, TRUE, nil, 0);
+					state = 1;
+				}
+			}else{
+				if(state==1 && t->what==Textarea){
+					textsetselect(t, q0, t->q1);
+					state = 0;
+				}else if(state != -1){
+					paste(t, t, TRUE, FALSE, nil, 0);
+					state = -1;
+				}
+			}
+			textscrdraw(t);
+		}
+		flushimage(display, 1);
+		while(mouse->buttons == b)
+			readmouse(mousectl);
+		clicktext = nil;
+	}
+}
+
+void
+textshow(Text *t, uint q0, uint q1, int doselect)
+{
+	int qe;
+	int nl;
+	uint q;
+
+	if(t->what != Textarea){
+		if(doselect)
+			textsetselect(t, q0, q1);
+		return;
+	}
+	if(doselect)
+		textsetselect(t, q0, q1);
+	qe = t->org+t->nchars;
+	if(t->org<=q0 && (q0<qe || (q0==qe && qe==t->rs.nr)))
+		textscrdraw(t);
+	else{
+		nl = t->maxlines/4;
+		q = textbacknl(t, q0, nl);
+		/* avoid going backwards if trying to go forwards - long lines! */
+		if(!(q0>t->org && q<t->org))
+			textsetorigin(t, q, TRUE);
+		while(q0 > t->org+t->nchars)
+			textsetorigin(t, t->org+1, FALSE);
+	}
+}
+
+static
+int
+region(int a, int b)
+{
+	if(a < b)
+		return -1;
+	if(a == b)
+		return 0;
+	return 1;
+}
+
+void
+selrestore(Frame *f, Point pt0, uint p0, uint p1)
+{
+	if(p1<=f->p0 || p0>=f->p1){
+		/* no overlap */
+		frdrawsel0(f, pt0, p0, p1, f->cols[BACK], f->cols[TEXT]);
+		return;
+	}
+	if(p0>=f->p0 && p1<=f->p1){
+		/* entirely inside */
+		frdrawsel0(f, pt0, p0, p1, f->cols[HIGH], f->cols[HTEXT]);
+		return;
+	}
+
+	/* they now are known to overlap */
+
+	/* before selection */
+	if(p0 < f->p0){
+		frdrawsel0(f, pt0, p0, f->p0, f->cols[BACK], f->cols[TEXT]);
+		p0 = f->p0;
+		pt0 = frptofchar(f, p0);
+	}
+	/* after selection */
+	if(p1 > f->p1){
+		frdrawsel0(f, frptofchar(f, f->p1), f->p1, p1, f->cols[BACK], f->cols[TEXT]);
+		p1 = f->p1;
+	}
+	/* inside selection */
+	frdrawsel0(f, pt0, p0, p1, f->cols[HIGH], f->cols[HTEXT]);
+}
+
+void
+textsetselect(Text *t, uint q0, uint q1)
+{
+	int p0, p1;
+
+	/* t->p0 and t->p1 are always right; t->q0 and t->q1 may be off */
+	t->q0 = q0;
+	t->q1 = q1;
+	/* compute desired p0,p1 from q0,q1 */
+	p0 = q0-t->org;
+	p1 = q1-t->org;
+	if(p0 < 0)
+		p0 = 0;
+	if(p1 < 0)
+		p1 = 0;
+	if(p0 > t->nchars)
+		p0 = t->nchars;
+	if(p1 > t->nchars)
+		p1 = t->nchars;
+	if(p0==t->p0 && p1==t->p1)
+		return;
+	/* screen disagrees with desired selection */
+	if(t->p1<=p0 || p1<=t->p0 || p0==p1 || t->p1==t->p0){
+		/* no overlap or too easy to bother trying */
+		frdrawsel(t, frptofchar(t, t->p0), t->p0, t->p1, 0);
+		frdrawsel(t, frptofchar(t, p0), p0, p1, 1);
+		goto Return;
+	}
+	/* overlap; avoid unnecessary painting */
+	if(p0 < t->p0){
+		/* extend selection backwards */
+		frdrawsel(t, frptofchar(t, p0), p0, t->p0, 1);
+	}else if(p0 > t->p0){
+		/* trim first part of selection */
+		frdrawsel(t, frptofchar(t, t->p0), t->p0, p0, 0);
+	}
+	if(p1 > t->p1){
+		/* extend selection forwards */
+		frdrawsel(t, frptofchar(t, t->p1), t->p1, p1, 1);
+	}else if(p1 < t->p1){
+		/* trim last part of selection */
+		frdrawsel(t, frptofchar(t, p1), p1, t->p1, 0);
+	}
+
+    Return:
+	t->p0 = p0;
+	t->p1 = p1;
+}
+
+
+/*
+ * Release the button in less than DELAY ms and it's considered a null selection
+ * if the mouse hardly moved, regardless of whether it crossed a char boundary.
+ */
+enum {
+	DELAY = 2,
+	MINMOVE = 4,
+};
+
+uint
+xselect(Frame *f, Mousectl *mc, Image *col, uint *p1p)	/* when called, button is down */
+{
+	uint p0, p1, q, tmp;
+	ulong msec;
+	Point mp, pt0, pt1, qt;
+	int reg, b;
+
+	mp = mc->xy;
+	b = mc->buttons;
+	msec = mc->msec;
+
+	/* remove tick */
+	if(f->p0 == f->p1)
+		frtick(f, frptofchar(f, f->p0), 0);
+	p0 = p1 = frcharofpt(f, mp);
+	pt0 = frptofchar(f, p0);
+	pt1 = frptofchar(f, p1);
+	reg = 0;
+	frtick(f, pt0, 1);
+	do{
+		q = frcharofpt(f, mc->xy);
+		if(p1 != q){
+			if(p0 == p1)
+				frtick(f, pt0, 0);
+			if(reg != region(q, p0)){	/* crossed starting point; reset */
+				if(reg > 0)
+					selrestore(f, pt0, p0, p1);
+				else if(reg < 0)
+					selrestore(f, pt1, p1, p0);
+				p1 = p0;
+				pt1 = pt0;
+				reg = region(q, p0);
+				if(reg == 0)
+					frdrawsel0(f, pt0, p0, p1, col, display->white);
+			}
+			qt = frptofchar(f, q);
+			if(reg > 0){
+				if(q > p1)
+					frdrawsel0(f, pt1, p1, q, col, display->white);
+
+				else if(q < p1)
+					selrestore(f, qt, q, p1);
+			}else if(reg < 0){
+				if(q > p1)
+					selrestore(f, pt1, p1, q);
+				else
+					frdrawsel0(f, qt, q, p1, col, display->white);
+			}
+			p1 = q;
+			pt1 = qt;
+		}
+		if(p0 == p1)
+			frtick(f, pt0, 1);
+		flushimage(f->display, 1);
+		readmouse(mc);
+	}while(mc->buttons == b);
+	if(mc->msec-msec < DELAY && p0!=p1
+	&& abs(mp.x-mc->xy.x)<MINMOVE
+	&& abs(mp.y-mc->xy.y)<MINMOVE) {
+		if(reg > 0)
+			selrestore(f, pt0, p0, p1);
+		else if(reg < 0)
+			selrestore(f, pt1, p1, p0);
+		p1 = p0;
+	}
+	if(p1 < p0){
+		tmp = p0;
+		p0 = p1;
+		p1 = tmp;
+	}
+	pt0 = frptofchar(f, p0);
+	if(p0 == p1)
+		frtick(f, pt0, 0);
+	selrestore(f, pt0, p0, p1);
+	/* restore tick */
+	if(f->p0 == f->p1)
+		frtick(f, frptofchar(f, f->p0), 1);
+	flushimage(f->display, 1);
+	*p1p = p1;
+	return p0;
+}
+
+int
+textselect23(Text *t, uint *q0, uint *q1, Image *high, int mask)
+{
+	uint p0, p1;
+	int buts;
+
+	p0 = xselect(t, mousectl, high, &p1);
+	buts = mousectl->buttons;
+	if((buts & mask) == 0){
+		*q0 = p0+t->org;
+		*q1 = p1+t->org;
+	}
+
+	while(mousectl->buttons)
+		readmouse(mousectl);
+	return buts;
+}
+
+int
+textselect2(Text *t, uint *q0, uint *q1, Text **tp)
+{
+	int buts;
+
+	*tp = nil;
+	buts = textselect23(t, q0, q1, but2col, 4);
+	if(buts & 4)
+		return 0;
+	if(buts & 1){	/* pick up argument */
+		*tp = argtext;
+		return 1;
+	}
+	return 1;
+}
+
+int
+textselect3(Text *t, uint *q0, uint *q1)
+{
+	int h;
+
+	h = (textselect23(t, q0, q1, but3col, 1|2) == 0);
+	return h;
+}
+
+static Rune left1[] =  { L'{', L'[', L'(', L'<', L'«', 0 };
+static Rune right1[] = { L'}', L']', L')', L'>', L'»', 0 };
+static Rune left2[] =  { L'\n', 0 };
+static Rune left3[] =  { L'\'', L'"', L'`', 0 };
+
+static
+Rune *left[] = {
+	left1,
+	left2,
+	left3,
+	nil
+};
+static
+Rune *right[] = {
+	right1,
+	left2,
+	left3,
+	nil
+};
+
+void
+textdoubleclick(Text *t, uint *q0, uint *q1)
+{
+	int c, i;
+	Rune *r, *l, *p;
+	uint q;
+
+	if(t->rs.nr == 0)
+		return;
+
+	for(i=0; left[i]!=nil; i++){
+		q = *q0;
+		l = left[i];
+		r = right[i];
+		/* try matching character to left, looking right */
+		if(q == 0)
+			c = '\n';
+		else
+			c = t->rs.r[q-1];
+		p = runestrchr(l, c);
+		if(p != nil){
+			if(textclickmatch(t, c, t->rs.r[p-l], 1, &q))
+				*q1 = q-(c!='\n');
+			return;
+		}
+		/* try matching character to right, looking left */
+		if(q == t->rs.nr)
+			c = '\n';
+		else
+			c = t->rs.r[q];
+		p = runestrchr(r, c);
+		if(p != nil){
+			if(textclickmatch(t, c, l[p-r], -1, &q)){
+				*q1 = *q0+(*q0<t->rs.nr && c=='\n');
+				*q0 = q;
+				if(c!='\n' || q!=0 || t->rs.r[0]=='\n')
+					(*q0)++;
+			}
+			return;
+		}
+	}
+	/* try filling out word to right */
+	while(*q1<t->rs.nr && isalnum(t->rs.r[*q1]))
+		(*q1)++;
+	/* try filling out word to left */
+	while(*q0>0 && isalnum(t->rs.r[*q0-1]))
+		(*q0)--;
+}
+
+int
+textclickmatch(Text *t, int cl, int cr, int dir, uint *q)
+{
+	Rune c;
+	int nest;
+
+	nest = 1;
+	for(;;){
+		if(dir > 0){
+			if(*q == t->rs.nr)
+				break;
+			c = t->rs.r[*q];
+			(*q)++;
+		}else{
+			if(*q == 0)
+				break;
+			(*q)--;
+			c = t->rs.r[*q];
+		}
+		if(c == cr){
+			if(--nest==0)
+				return 1;
+		}else if(c == cl)
+			nest++;
+	}
+	return cl=='\n' && nest==1;
+}
+
+uint
+textbacknl(Text *t, uint p, uint n)
+{
+	int i, j;
+
+	/* look for start of this line if n==0 */
+	if(n==0 && p>0 && t->rs.r[p-1]!='\n')
+		n = 1;
+	i = n;
+	while(i-->0 && p>0){
+		--p;	/* it's at a newline now; back over it */
+		if(p == 0)
+			break;
+		/* at 128 chars, call it a line anyway */
+		for(j=128; --j>0 && p>0; p--)
+			if(t->rs.r[p-1]=='\n')
+				break;
+	}
+	return p;
+}
+
+void
+textsetorigin(Text *t, uint org, int exact)
+{
+	int i, a, fixup;
+	Rune *r;
+	uint n;
+
+	if(org>0 && !exact){
+		/* org is an estimate of the char posn; find a newline */
+		/* don't try harder than 256 chars */
+		for(i=0; i<256 && org<t->rs.nr; i++){
+			if(t->rs.r[org] == '\n'){
+				org++;
+				break;
+			}
+			org++;
+		}
+	}
+	a = org-t->org;
+	fixup = 0;
+	if(a>=0 && a<t->nchars){
+		frdelete(t, 0, a);
+		fixup = 1;	/* frdelete can leave end of last line in wrong selection mode; it doesn't know what follows */
+	}else if(a<0 && -a<t->nchars){
+		n = t->org - org;
+		r = runemalloc(n);
+		runemove(r, t->rs.r+org, n);
+		frinsert(t, r, r+n, 0);
+		free(r);
+	}else
+		frdelete(t, 0, t->nchars);
+	t->org = org;
+	textfill(t);
+	textscrdraw(t);
+	textsetselect(t, t->q0, t->q1);
+	if(fixup && t->p1 > t->p0)
+		frdrawsel(t, frptofchar(t, t->p1-1), t->p1-1, t->p1, 1);
+}
+
+void
+textset(Text *t, Rune*r, int n)
+{
+	textdelete(t, 0, t->rs.nr);
+	textinsert(t, 0, r, n);
+	textsetselect(t, t->q0, t->q1);
+}
+
+void
+textmouse(Text *t, Point xy, int but)
+{
+	Text *argt;
+	uint q0, q1;
+
+	if(ptinrect(xy, t->scrollr)){
+		if(t->what == Columntag)
+			rowdragcol(&row, t->col, but);
+		else if(t->what == Tag)
+			coldragwin(t->col, t->w, but);
+		else if(t->what == Textarea)
+			textscroll(t, but);
+		if(t->col)
+			activecol = t->col;
+		return;
+	}
+	if(but == 1){
+		selpage = nil;
+		textselect(t);
+		argtext = t;
+		seltext = t;
+	}else if(but == 2){
+		if(textselect2(t, &q0, &q1, &argt))
+			execute(t, q0, q1, argt);
+	}else if(but == 3){
+		if(textselect3(t, &q0, &q1))
+			look3(t, q0, q1);
+	}
+}