#include <u.h>#include <libc.h>#include <draw.h>#include <thread.h>#include <mouse.h>#include <frame.h> #define	SLOP	25 void_fraddbox(Frame *f, int bn, int n)	/* add n boxes after bn, shift the rest up,				 * box[bn+n]==box[bn] */{	int i; 	if(bn > f->nbox)		drawerror(f->display, "_fraddbox");	if(f->nbox+n > f->nalloc)		_frgrowbox(f, n+SLOP);	for(i=f->nbox; --i>=bn; )		f->box[i+n] = f->box[i];	f->nbox+=n;} void_frclosebox(Frame *f, int n0, int n1)	/* inclusive */{	int i; 	if(n0>=f->nbox || n1>=f->nbox || n1<n0)		drawerror(f->display, "_frclosebox");	n1++;	for(i=n1; i<f->nbox; i++)		f->box[i-(n1-n0)] = f->box[i];	f->nbox -= n1-n0;} void_frdelbox(Frame *f, int n0, int n1)	/* inclusive */{	if(n0>=f->nbox || n1>=f->nbox || n1<n0)		drawerror(f->display, "_frdelbox");	_frfreebox(f, n0, n1);	_frclosebox(f, n0, n1);} void_frfreebox(Frame *f, int n0, int n1)	/* inclusive */{	int i; 	if(n1<n0)		return;	if(n0>=f->nbox || n1>=f->nbox)		drawerror(f->display, "_frfreebox");	n1++;	for(i=n0; i<n1; i++)		if(f->box[i].nrune >= 0)			free(f->box[i].ptr);} void_frgrowbox(Frame *f, int delta){	f->nalloc += delta;	f->box = realloc(f->box, f->nalloc*sizeof(Frbox));	if(f->box == 0)		drawerror(f->display, "_frgrowbox");} staticvoiddupbox(Frame *f, int bn){	uchar *p; 	if(f->box[bn].nrune < 0)		drawerror(f->display, "dupbox");	_fraddbox(f, bn, 1);	if(f->box[bn].nrune >= 0){		p = _frallocstr(f, NBYTE(&f->box[bn])+1);		strcpy((char*)p, (char*)f->box[bn].ptr);		f->box[bn+1].ptr = p;	}} staticuchar*runeindex(uchar *p, int n){	int i, w;	Rune rune; 	for(i=0; i<n; i++,p+=w)		if(*p < Runeself)			w = 1;		else{			w = chartorune(&rune, (char*)p);			USED(rune);		}	return p;} staticvoidtruncatebox(Frame *f, Frbox *b, int n)	/* drop last n chars; no allocation done */{	if(b->nrune<0 || b->nrune<n)		drawerror(f->display, "truncatebox");	b->nrune -= n;	runeindex(b->ptr, b->nrune)[0] = 0;	b->wid = stringwidth(f->font, (char *)b->ptr);} staticvoidchopbox(Frame *f, Frbox *b, int n)	/* drop first n chars; no allocation done */{	char *p; 	if(b->nrune<0 || b->nrune<n)		drawerror(f->display, "chopbox");	p = (char*)runeindex(b->ptr, n);	memmove((char*)b->ptr, p, strlen(p)+1);	b->nrune -= n;	b->wid = stringwidth(f->font, (char *)b->ptr);} void_frsplitbox(Frame *f, int bn, int n){	dupbox(f, bn);	truncatebox(f, &f->box[bn], f->box[bn].nrune-n);	chopbox(f, &f->box[bn+1], n);} void_frmergebox(Frame *f, int bn)		/* merge bn and bn+1 */{	Frbox *b; 	b = &f->box[bn];	_frinsure(f, bn, NBYTE(&b[0])+NBYTE(&b[1])+1);	strcpy((char*)runeindex(b[0].ptr, b[0].nrune), (char*)b[1].ptr);	b[0].wid += b[1].wid;	b[0].nrune += b[1].nrune;	_frdelbox(f, bn+1, bn+1);} int_frfindbox(Frame *f, int bn, ulong p, ulong q)	/* find box containing q and put q on a box boundary */{	Frbox *b; 	for(b = &f->box[bn]; bn<f->nbox && p+NRUNE(b)<=q; bn++, b++)		p += NRUNE(b);	if(p != q)		_frsplitbox(f, bn++, (int)(q-p));	return bn;}