#include <u.h>#include <libc.h> #define	ISDIR	0x80000000L long	du(char *, Dir *);long	k(long);void	err(char *);int	warn(char *);int	seen(Dir *);int	aflag=0;char	fmt[] = "%lud\t%s\n";long	blocksize = 1024; voidmain(int argc, char *argv[]){	int i;	char *s, *ss; 	ARGBEGIN{	case 'a':	aflag=1; break;	case 'b':		s = ARGF();		blocksize = strtoul(s, &ss, 0);		if(s == ss)			blocksize = 1;		if(*ss == 'k')			blocksize *= 1024;		break;	}ARGEND	if(argc==0)		print(fmt, du(".", (Dir*)0), ".");	else	for(i=0; i<argc; i++)		print(fmt, du(argv[i], (Dir*)0), argv[i]);	exits(0);} longdu(char *name, Dir *dir){	int fd, i, n;	Dir buf[25], b;	char file[256];	long nk, t; 	if(dir==0){		dir=&buf[0];		if(dirstat(name, dir)<0)			return warn(name);		if((dir->mode&ISDIR)==0)			return k(dir->length);	}	fd=open(name, OREAD);	if(fd<0)		return warn(name);	nk=0;	while((n=dirread(fd, buf, sizeof buf))>0){		n/=sizeof(Dir);		dir=buf;		for(i=0; i<n; i++, dir++){			if((dir->mode&ISDIR)==0){				t=k(dir->length);				nk+=t;				if(aflag){					sprint(file, "%s/%s", name, dir->name);					print(fmt, t, file);				}				continue;			}			if(strcmp(dir->name, ".")==0 || strcmp(dir->name, "..")==0 || seen(dir))				continue;			sprint(file, "%s/%s", name, dir->name);			if(dirstat(file, &b)<0){				warn(file);				continue;			}			if(b.qid.path!=dir->qid.path ||			   b.dev!=dir->dev || b.type!=dir->type)				continue;	/* file is hidden */			t=du(file, dir);			print(fmt, t, file);			nk+=t;		}	}	if(n<0)		warn("name");	close(fd);	return nk;} #define	NCACHE	128	/* must be power of two */struct cache{	Dir	*cache;	int	n;	int	max;} cache[NCACHE]; intseen(Dir *dir){	Dir *dp;	int i;	struct cache *c; 	c = &cache[dir->qid.path&(NCACHE-1)];	dp = c->cache;	for(i=0; i<c->n; i++,dp++)		if(dir->qid.path==dp->qid.path &&		   dir->type==dp->type && dir->dev==dp->dev)			return 1;	if(c->n == c->max){		c->cache = realloc(c->cache, (c->max+=20)*sizeof(Dir));		if(cache == 0)			err("malloc failure");	}	c->cache[c->n++] = *dir;	return 0;} voiderr(char *s){	fprint(2, "du: ");	perror(s);	exits(s);} intwarn(char *s){	fprint(2, "du: ");	perror(s);	return 0;} longk(long n){	n = (n+blocksize-1)/blocksize;	return n*blocksize/1024;}