/*  * This file is part of the UCB release of Plan 9. It is subject to the license * terms in the LICENSE file found in the top-level directory of this * distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No * part of the UCB release of Plan 9, including this file, may be copied, * modified, propagated, or distributed except according to the terms contained * in the LICENSE file. */ #include "sam.h" voidmoveto(File *f, Range r){	Posn p1 = r.p1, p2 = r.p2; 	f->dot.r.p1 = p1;	f->dot.r.p2 = p2;	if(f->rasp){		telldot(f);		outTsl(Hmoveto, f->tag, f->dot.r.p1);	}} voidtelldot(File *f){	if(f->rasp == 0)		panic("telldot");	if(f->dot.r.p1==f->tdot.p1 && f->dot.r.p2==f->tdot.p2)		return;	outTsll(Hsetdot, f->tag, f->dot.r.p1, f->dot.r.p2);	f->tdot = f->dot.r;} voidtellpat(void){	outTS(Hsetpat, &lastpat);	patset = FALSE;} #define	CHARSHIFT	128 voidlookorigin(File *f, Posn p0, Posn ls){	int nl, nc, c;	Posn p, oldp0; 	if(p0 > f->nc)		p0 = f->nc;	oldp0 = p0;	p = p0;	for(nl=nc=c=0; c!=-1 && nl<ls && nc<ls*CHARSHIFT; nc++)		if((c=filereadc(f, --p)) == '\n'){			nl++;			oldp0 = p0-nc;		}	if(c == -1)		p0 = 0;	else if(nl==0){		if(p0>=CHARSHIFT/2)			p0-=CHARSHIFT/2;		else			p0 = 0;	}else		p0 = oldp0;	outTsl(Horigin, f->tag, p0);} intalnum(int c){	/*	 * Hard to get absolutely right.  Use what we know about ASCII	 * and assume anything above the Latin control characters is	 * potentially an alphanumeric.	 */	if(c<=' ')		return 0;	if(0x7F<=c && c<=0xA0)		return 0;	if(utfrune("!\"#$%&'()*+,-./:;<=>?@[\\]^`{|}~", c))		return 0;	return 1;} intclickmatch(File *f, int cl, int cr, int dir, Posn *p){	int c;	int nest = 1; 	for(;;){		if(dir > 0){			if(*p >= f->nc)				break;			c = filereadc(f, (*p)++);		}else{			if(*p == 0)				break;			c = filereadc(f, --(*p));		}		if(c == cr){			if(--nest==0)				return 1;		}else if(c == cl)			nest++;	}	return cl=='\n' && nest==1;} Rune*strrune(Rune *s, Rune c){	Rune c1; 	if(c == 0) {		while(*s++)			;		return s-1;	} 	while(c1 = *s++)		if(c1 == c)			return s-1;	return 0;} voiddoubleclick(File *f, Posn p1){	int c, i;	Rune *r, *l;	Posn p; 	if(p1 > f->nc)		return;	f->dot.r.p1 = f->dot.r.p2 = p1;	for(i=0; left[i]; i++){		l = left[i];		r = right[i];		/* try left match */		p = p1;		if(p1 == 0)			c = '\n';		else			c = filereadc(f, p - 1);		if(strrune(l, c)){			if(clickmatch(f, c, r[strrune(l, c)-l], 1, &p)){				f->dot.r.p1 = p1;				f->dot.r.p2 = p-(c!='\n');			}			return;		}		/* try right match */		p = p1;		if(p1 == f->nc)			c = '\n';		else			c = filereadc(f, p);		if(strrune(r, c)){			if(clickmatch(f, c, l[strrune(r, c)-r], -1, &p)){				f->dot.r.p1 = p;				if(c!='\n' || p!=0 || filereadc(f, 0)=='\n')					f->dot.r.p1++;				f->dot.r.p2 = p1+(p1<f->nc && c=='\n');			}			return;		}	}	/* try filling out word to right */	p = p1;	while(p < f->nc && alnum(filereadc(f, p++)))		f->dot.r.p2++;	/* try filling out word to left */	p = p1;	while(--p >= 0 && alnum(filereadc(f, p)))		f->dot.r.p1--;}