#include <u.h>#include <libc.h>#include <libg.h>#include <frame.h> voidfrselect(Frame *f, Mouse *m)	/* when called, button 1 is down */{	ulong p0, p1, q;	Point mp, pt0, pt1, qt;	int b; 	b = m->buttons;	mp = m->xy;     Again:	f->modified = 0;	frselectp(f, F&~D);	p0 = p1 = frcharofpt(f, mp);	pt0 = frptofchar(f, p0);	pt1 = frptofchar(f, p1);	frselectf(f, pt0, pt1, F&~D);	do{		if(f->modified)	/* special hack so 8½ can frselect in parallel */			goto Again;		q = frcharofpt(f, m->xy);		if(p1 != q){			if(p0 == p1)				frselectf(f, pt0, pt1, F&~D);			qt = frptofchar(f, q);			if(p1 < q)				frselectf(f, pt1, qt, F&~D);			else				frselectf(f, qt, pt1, F&~D);			p1 = q;			pt1 = qt;			if(p0 == p1)				frselectf(f, pt0, pt1, F&~D);		}		f->modified = 0;		if(p0 < p1)			f->p0 = p0, f->p1 = p1;		else			f->p0 = p1, f->p1 = p0;		frgetmouse();	}while(m->buttons == b);}/* it is assumed p0<=p1 and both were generated by frptofchar() */voidfrselectf(Frame *f, Point p0, Point p1, Fcode c){	int n;	Point q0, q1; 	if(p0.x == f->left)		p0.x = f->r.min.x;	if(p1.x == f->left)		p1.x = f->r.min.x;	q0 = p0;	q1 = p1;	q0.y += f->font->height;	q1.y += f->font->height;	n = (p1.y-p0.y)/f->font->height;	if(f->b == 0)		berror("frselectf b==0");	if(p0.y == f->r.max.y)		return;	if(n == 0){		if(p0.x == p1.x)			if(p0.x == f->r.min.x)				q1.x++;			else				p0.x--;		bitblt(f->b, p0, f->b, Rpt(p0, q1), c);	}else{		if(p0.x >= f->r.max.x)			p0.x = f->r.max.x-1;		bitblt(f->b, p0, f->b, Rect(p0.x, p0.y, f->r.max.x, q0.y), c);		if(n > 1)			bitblt(f->b, Pt(f->r.min.x, q0.y),				f->b, Rect(f->r.min.x, q0.y, f->r.max.x, p1.y), c);		bitblt(f->b, Pt(f->r.min.x, p1.y),				f->b, Rect(f->r.min.x, p1.y, q1.x, q1.y), c);	}} voidfrselectp(Frame *f, Fcode c){	Point pt0, pt1; 	pt0 = frptofchar(f, f->p0);	pt1 = (f->p0==f->p1)? pt0 : frptofchar(f, f->p1);	frselectf(f, pt0, pt1, c);}