#include <lib9.h>#include <image.h>#include <kernel.h> Image*allocimage(Display *d, Rectangle r, int ld, int repl, int val){	return _allocimage(d, r, ld, repl, val, 0, 0);} Image*_allocimage(Display *d, Rectangle r, int ld, int repl, int val, int screenid, int refresh){	uchar *a;	char *err;	Image *i;	Rectangle clipr;	int id; 	err = 0;	i = 0; 	if(ld<0 || ld>3){		err = "invalid ldepth";    Error:		if(err)			kwerrstr("allocimage: %s", err);		else			kwerrstr("allocimage: %r");		if(i)			free(i);		return 0;	} 	a = bufimage(d, 1+4+4+1+2+1+4*4+4*4+1);	if(a == 0)		goto Error;	d->imageid++;	id = d->imageid;	a[0] = 'a';	BPLONG(a+1, id);	BPLONG(a+5, screenid);	a[9] = refresh;	BPSHORT(a+10, ld);	a[12] = repl;	BPLONG(a+13, r.min.x);	BPLONG(a+17, r.min.y);	BPLONG(a+21, r.max.x);	BPLONG(a+25, r.max.y);	if(repl)		/* huge but not infinite, so various offsets will leave it huge, not overflow */		clipr = Rect(-0x3FFFFFFF, -0x3FFFFFFF, 0x3FFFFFFF, 0x3FFFFFFF);	else		clipr = r;	BPLONG(a+29, clipr.min.x);	BPLONG(a+33, clipr.min.y);	BPLONG(a+37, clipr.max.x);	BPLONG(a+41, clipr.max.y);	a[45] = val;	if(flushimage(d, 0) < 0)		goto Error; 	i = malloc(sizeof(Image));	if(i == nil){		a = bufimage(d, 1+4);		if(a){			a[0] = 'f';			BPLONG(a+1, id);			flushimage(d, 0);		}		goto Error;	}	i->display = d;	i->id = id;	i->ldepth = ld;	i->r = r;	i->clipr = clipr;	i->repl = repl;	i->screen = 0;	i->next = 0;	return i;} intfreeimage(Image *i){	uchar *a;	Display *d;	Image *w; 	if(i == 0)		return 0;	/* make sure no refresh events occur on this if we block in the write */	i->refptr = nil;	d = i->display;	a = bufimage(d, 1+4);	if(a == 0)		return 0;	a[0] = 'f';	BPLONG(a+1, i->id);	if(i->screen){		w = d->windows;		if(w == i)			d->windows = i->next;		else			while(w){				if(w->next == i){					w->next = i->next;					break;				}				w = w->next;			}	}	if(flushimage(d, i->screen!=0) < 0)		return -1; 	free(i);	return 0;}