#include <u.h>#include <libc.h> char	errbuf[ERRLEN];Dir	*dirbuf;long	ndirbuf = 0;int	ignerr = 0; voiderr(char *f){	if(!ignerr){		errstr(errbuf);		fprint(2, "rm: %s: %s\n", f, errbuf);	}} /* * Read a whole directory before removing anything as the holes formed * by removing affect the read offset. */longreaddirect(int fd){	enum	{		N = 32	};	long m, n; 	m = 1;	/* prime the loop */	for(n=0; m>0; n+=m/sizeof(Dir)){		if(n == ndirbuf){			dirbuf = realloc(dirbuf, (ndirbuf+N)*sizeof(Dir));			if(dirbuf == 0){				err("memory allocation");				exits(errbuf);			}			ndirbuf += N;		}		m = dirread(fd, dirbuf+n, (ndirbuf-n)*sizeof(Dir));	}	return n;} /* * f is a non-empty directory. Remove its contents and then it. */voidrmdir(char *f){	char *name;	Dir *db;	int fd, i, j, n, ndir; 	fd = open(f, OREAD);	if(fd < 0){		err(f);		return;	}	n = readdirect(fd);	close(fd); 	name = malloc(strlen(f)+1+NAMELEN);	if(name == 0){		err("memory allocation");		return;	} 	ndir = 0;	for(i=0; i<n; i++){		sprint(name, "%s/%s", f, dirbuf[i].name);		if(remove(name) != -1)			dirbuf[i].qid.path = 0;	/* so we won't recurse */		else{			if(dirbuf[i].qid.path & CHDIR)				ndir++;			else				err(name);		}	}	if(ndir){		/*		 * Recursion will smash dirbuf, so make a local copy		 */		db = malloc(ndir*sizeof(Dir));		if(db == 0){			err("memory allocation");			free(name);			return;		}		for(j=0,i=0; i<n; i++)			if(dirbuf[i].qid.path & 0x80000000L)				db[j++] = dirbuf[i];		/*		 * Everything we need is in db now		 */		for(j=0; j<ndir; j++){			sprint(name, "%s/%s", f, db[j].name);			rmdir(name);		}		free(db);	}	if(remove(f) == -1)		err(f);	free(name);}voidmain(int argc, char *argv[]){	int i;	int recurse;	char *f;	Dir db; 	ignerr = 0;	recurse = 0;	ARGBEGIN{	case 'r':		recurse = 1;		break;	case 'f':		ignerr = 1;		break;	default:		fprint(2, "usage: rm [-fr] file ...\n");		exits("usage");	}ARGEND	for(i=0; i<argc; i++){		f = argv[i];		if(remove(f) != -1)			continue;		if(recurse && dirstat(f, &db)!=-1 && (db.qid.path&CHDIR))			rmdir(f);		else			err(f);	}	exits(errbuf);}