add new guys

src/cmd/news.c

@@ -0,0 +1,231 @@
+/*
+ *	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 = "#9/news";
+char	TFILE[] = "%s/lib/newstime";
+
+/*
+ *	The following items should not be printed.
+ */
+char*	ignore[] =
+{
+	"core",
+	"dead.letter",
+	0
+};
+
+typedef
+struct
+{
+	long	time;
+	char	*name;
+	vlong	length;
+} File;
+File*	n_list;
+int	n_count;
+int	n_items;
+Biobuf	bout;
+
+int	fcmp(const void *a, const 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);
+
+void
+main(int argc, char *argv[])
+{
+	int i;
+
+	NEWS = unsharp(NEWS);
+
+	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);
+}
+
+int
+fcmp(const void *a, const 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.
+ */
+void
+read_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);
+}
+
+void
+print_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);
+}
+
+void
+eachitem(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);
+	}
+}
+
+void
+note(char *file)
+{
+
+	if(!n_items)
+		Bprint(&bout, "news:");
+	Bprint(&bout, " %s", file);
+	n_items++;
+}