/*  * 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. */ /* *	news foo	prints /lib/news/foo *	news -a		prints all news items, latest first *	news -n		lists names of new items *	news		prints items changed since last news */ #include <u.h>#include <libc.h>#include <bio.h> #define	NINC	50	/* Multiples of directory allocation */char	NEWS[] = "/lib/news";char	TFILE[] = "%s/lib/newstime"; /* *	The following items should not be printed. */char*	ignore[] ={	"core",	"dead.letter",	0}; typedefstruct{	long	time;	char	*name;	vlong	length;} File;File*	n_list;int	n_count;int	n_items;Biobuf	bout; int	fcmp(void *a, void *b);void	read_dir(int update);void	print_item(char *f);void	eachitem(void (*emit)(char*), int all, int update);void	note(char *s); voidmain(int argc, char *argv[]){	int i; 	Binit(&bout, 1, OWRITE);	if(argc == 1) {		eachitem(print_item, 0, 1);		exits(0);	}	ARGBEGIN{	case 'a':	/* print all */		eachitem(print_item, 1, 0);		break; 	case 'n':	/* names only */		eachitem(note, 0, 0);		if(n_items)			Bputc(&bout, '\n');		break; 	default:		fprint(2, "news: bad option %c\n", ARGC());		exits("usage");	}ARGEND	for(i=0; i<argc; i++)		print_item(argv[i]);	exits(0);} intfcmp(void *a, void *b){	long x; 	x = ((File*)b)->time - ((File*)a)->time;	if(x < 0)		return -1;	if(x > 0)		return 1;	return 0;} /* *	read_dir: get the file names and modification dates for the *	files in /usr/news into n_list; sort them in reverse by *	modification date. */voidread_dir(int update){	Dir *d;	char newstime[100], *home;	int i, j, n, na, fd; 	n_count = 0;	n_list = malloc(NINC*sizeof(File));	na = NINC;	home = getenv("home");	if(home) {		sprint(newstime, TFILE, home);		d = dirstat(newstime);		if(d != nil) {			n_list[n_count].name = strdup("");			n_list[n_count].time =d->mtime-1;			n_list[n_count].length = 0;			n_count++;			free(d);		}		if(update) {			fd = create(newstime, OWRITE, 0644);			if(fd >= 0)				close(fd);		}	}	fd = open(NEWS, OREAD);	if(fd < 0) {		fprint(2, "news: ");		perror(NEWS);		exits(NEWS);	} 	n = dirreadall(fd, &d);	for(i=0; i<n; i++) {		for(j=0; ignore[j]; j++)			if(strcmp(ignore[j], d[i].name) == 0)				goto ign;		if(na <= n_count) {			na += NINC;			n_list = realloc(n_list, na*sizeof(File));		}		n_list[n_count].name = strdup(d[i].name);		n_list[n_count].time = d[i].mtime;		n_list[n_count].length = d[i].length;		n_count++;	ign:;	}	free(d); 	close(fd);	qsort(n_list, n_count, sizeof(File), fcmp);} voidprint_item(char *file){	char name[4096], *p, *ep;	Dir *dbuf;	int f, c;	int bol, bop; 	sprint(name, "%s/%s", NEWS, file);	f = open(name, OREAD);	if(f < 0) {		fprint(2, "news: ");		perror(name);		return;	}	strcpy(name, "...");	dbuf = dirfstat(f);	if(dbuf == nil)		return;	Bprint(&bout, "\n%s (%s) %s\n", file,		dbuf->muid[0]? dbuf->muid : dbuf->uid,		asctime(localtime(dbuf->mtime)));	free(dbuf); 	bol = 1;	/* beginning of line ...\n */	bop = 1;	/* beginning of page ...\n\n */	for(;;) {		c = read(f, name, sizeof(name));		if(c <= 0)			break;		p = name;		ep = p+c;		while(p < ep) {			c = *p++;			if(c == '\n') {				if(!bop) {					Bputc(&bout, c);					if(bol)						bop = 1;					bol = 1;				}				continue;			}			if(bol) {				Bputc(&bout, '\t');				bol = 0;				bop = 0;			}			Bputc(&bout, c);		}	}	if(!bol)		Bputc(&bout, '\n');	close(f);} voideachitem(void (*emit)(char*), int all, int update){	int i; 	read_dir(update);	for(i=0; i<n_count; i++) {		if(n_list[i].name[0] == 0) {	/* newstime */			if(all)				continue;			break;		}		if(n_list[i].length == 0)		/* in progress */			continue;		(*emit)(n_list[i].name);	}} voidnote(char *file){ 	if(!n_items)		Bprint(&bout, "news:");	Bprint(&bout, " %s", file);	n_items++;}