Use err(3). Add usage() and prototypes.

1 files changed, 55 insertions, 62 deletions

diff --git a/usr.bin/write/write.c b/usr.bin/write/write.c
index dd0248d..c05ab62 100644
--- a/usr.bin/write/write.c
+++ b/usr.bin/write/write.c
@@ -35,13 +35,17 @@
  */
 
 #ifndef lint
-static char copyright[] =
+static const char copyright[] =
 "@(#) Copyright (c) 1989, 1993\n\
 	The Regents of the University of California.  All rights reserved.\n";
 #endif /* not lint */
 
 #ifndef lint
+#if 0
 static char sccsid[] = "@(#)write.c	8.1 (Berkeley) 6/6/93";
+#endif
+static const char rcsid[] =
+	"$Id$";
 #endif /* not lint */
 
 #include <sys/param.h>
@@ -49,15 +53,24 @@ static char sccsid[] = "@(#)write.c	8.1 (Berkeley) 6/6/93";
 #include <sys/stat.h>
 #include <sys/file.h>
 #include <sys/time.h>
-#include <utmp.h>
 #include <ctype.h>
+#include <err.h>
 #include <paths.h>
 #include <pwd.h>
 #include <stdio.h>
 #include <string.h>
+#include <unistd.h>
+#include <utmp.h>
 
-extern int errno;
+void done __P((void));
+void do_write __P((char *, char *, uid_t));
+static void usage __P((void));
+int term_chk __P((char *, int *, time_t *, int));
+void wr_fputs __P((unsigned char *s));
+void search_utmp __P((char *, char *, char *, uid_t));
+int utmp_chk __P((char *, char *));
 
+int
 main(argc, argv)
 	int argc;
 	char **argv;
@@ -66,8 +79,7 @@ main(argc, argv)
 	time_t atime;
 	uid_t myuid;
 	int msgsok, myttyfd;
-	char tty[MAXPATHLEN], *mytty, *ttyname();
-	void done();
+	char tty[MAXPATHLEN], *mytty;
 
 	/* check that sender has write enabled */
 	if (isatty(fileno(stdin)))
@@ -76,23 +88,16 @@ main(argc, argv)
 		myttyfd = fileno(stdout);
 	else if (isatty(fileno(stderr)))
 		myttyfd = fileno(stderr);
-	else {
-		(void)fprintf(stderr, "write: can't find your tty\n");
-		exit(1);
-	}
-	if (!(mytty = ttyname(myttyfd))) {
-		(void)fprintf(stderr, "write: can't find your tty's name\n");
-		exit(1);
-	}
-	if (cp = rindex(mytty, '/'))
+	else
+		errx(1, "can't find your tty");
+	if (!(mytty = ttyname(myttyfd)))
+		errx(1, "can't find your tty's name");
+	if ((cp = rindex(mytty, '/')))
 		mytty = cp + 1;
 	if (term_chk(mytty, &msgsok, &atime, 1))
 		exit(1);
-	if (!msgsok) {
-		(void)fprintf(stderr,
-		    "write: you have write permission turned off.\n");
-		exit(1);
-	}
+	if (!msgsok)
+		errx(1, "you have write permission turned off");
 
 	myuid = getuid();
 
@@ -105,34 +110,33 @@ main(argc, argv)
 	case 3:
 		if (!strncmp(argv[2], _PATH_DEV, strlen(_PATH_DEV)))
 			argv[2] += strlen(_PATH_DEV);
-		if (utmp_chk(argv[1], argv[2])) {
-			(void)fprintf(stderr,
-			    "write: %s is not logged in on %s.\n",
-			    argv[1], argv[2]);
-			exit(1);
-		}
+		if (utmp_chk(argv[1], argv[2]))
+			errx(1, "%s is not logged in on %s", argv[1], argv[2]);
 		if (term_chk(argv[2], &msgsok, &atime, 1))
 			exit(1);
-		if (myuid && !msgsok) {
-			(void)fprintf(stderr,
-			    "write: %s has messages disabled on %s\n",
-			    argv[1], argv[2]);
-			exit(1);
-		}
+		if (myuid && !msgsok)
+			errx(1, "%s has messages disabled on %s", argv[1], argv[2]);
 		do_write(argv[2], mytty, myuid);
 		break;
 	default:
-		(void)fprintf(stderr, "usage: write user [tty]\n");
-		exit(1);
+		usage();
 	}
 	done();
-	/* NOTREACHED */
+	return (0);
+}
+
+static void
+usage()
+{
+	(void)fprintf(stderr, "usage: write user [tty]\n");
+	exit(1);
 }
 
 /*
  * utmp_chk - checks that the given user is actually logged in on
  *     the given tty
  */
+int
 utmp_chk(user, tty)
 	char *user, *tty;
 {
@@ -164,6 +168,7 @@ utmp_chk(user, tty)
  * Special case for writing to yourself - ignore the terminal you're
  * writing from, unless that's the only terminal with messages enabled.
  */
+void
 search_utmp(user, tty, mytty, myuid)
 	char *user, *tty, *mytty;
 	uid_t myuid;
@@ -173,10 +178,8 @@ search_utmp(user, tty, mytty, myuid)
 	int ufd, nloggedttys, nttys, msgsok, user_is_me;
 	char atty[UT_LINESIZE + 1];
 
-	if ((ufd = open(_PATH_UTMP, O_RDONLY)) < 0) {
-		perror("utmp");
-		exit(1);
-	}
+	if ((ufd = open(_PATH_UTMP, O_RDONLY)) < 0)
+		err(1, "utmp");
 
 	nloggedttys = nttys = 0;
 	bestatime = 0;
@@ -202,22 +205,16 @@ search_utmp(user, tty, mytty, myuid)
 		}
 
 	(void)close(ufd);
-	if (nloggedttys == 0) {
-		(void)fprintf(stderr, "write: %s is not logged in\n", user);
-		exit(1);
-	}
+	if (nloggedttys == 0)
+		errx(1, "%s is not logged in", user);
 	if (nttys == 0) {
 		if (user_is_me) {		/* ok, so write to yourself! */
 			(void)strcpy(tty, mytty);
 			return;
 		}
-		(void)fprintf(stderr,
-		    "write: %s has messages disabled\n", user);
-		exit(1);
+		errx(1, "%s has messages disabled", user);
 	} else if (nttys > 1) {
-		(void)fprintf(stderr,
-		    "write: %s is logged in more than once; writing to %s\n",
-		    user, tty);
+		warnx("%s is logged in more than once; writing to %s", user, tty);
 	}
 }
 
@@ -225,6 +222,7 @@ search_utmp(user, tty, mytty, myuid)
  * term_chk - check that a terminal exists, and get the message bit
  *     and the access time
  */
+int
 term_chk(tty, msgsokP, atimeP, showerror)
 	char *tty;
 	int *msgsokP, showerror;
@@ -236,8 +234,7 @@ term_chk(tty, msgsokP, atimeP, showerror)
 	(void)snprintf(path, sizeof(path), "%s%s", _PATH_DEV, tty);
 	if (stat(path, &s) < 0) {
 		if (showerror)
-			(void)fprintf(stderr,
-			    "write: %s: %s\n", path, strerror(errno));
+			warn("%s", path);
 		return(1);
 	}
 	*msgsokP = (s.st_mode & (S_IWRITE >> 3)) != 0;	/* group write bit */
@@ -248,28 +245,26 @@ term_chk(tty, msgsokP, atimeP, showerror)
 /*
  * do_write - actually make the connection
  */
+void
 do_write(tty, mytty, myuid)
 	char *tty, *mytty;
 	uid_t myuid;
 {
 	register char *login, *nows;
 	register struct passwd *pwd;
-	time_t now, time();
-	char *getlogin(), path[MAXPATHLEN], host[MAXHOSTNAMELEN], line[512];
-	void done();
+	time_t now;
+	char path[MAXPATHLEN], host[MAXHOSTNAMELEN], line[512];
 
 	/* Determine our login name before the we reopen() stdout */
 	if ((login = getlogin()) == NULL)
-		if (pwd = getpwuid(myuid))
+		if ((pwd = getpwuid(myuid)))
 			login = pwd->pw_name;
 		else
 			login = "???";
 
 	(void)snprintf(path, sizeof(path), "%s%s", _PATH_DEV, tty);
-	if ((freopen(path, "w", stdout)) == NULL) {
-		(void)fprintf(stderr, "write: %s: %s\n", path, strerror(errno));
-		exit(1);
-	}
+	if ((freopen(path, "w", stdout)) == NULL)
+		err(1, "%s", path);
 
 	(void)signal(SIGINT, done);
 	(void)signal(SIGHUP, done);
@@ -301,11 +296,12 @@ done()
  * wr_fputs - like fputs(), but makes control characters visible and
  *     turns \n into \r\n
  */
+void
 wr_fputs(s)
 	register unsigned char *s;
 {
 
-#define	PUTC(c)	if (putchar(c) == EOF) goto err;
+#define	PUTC(c)	if (putchar(c) == EOF) err(1, NULL);
 
 	for (; *s != '\0'; ++s) {
 		if (*s == '\n') {
@@ -324,8 +320,5 @@ wr_fputs(s)
 		PUTC(*s);
 	}
 	return;
-
-err:	(void)fprintf(stderr, "write: %s\n", strerror(errno));
-	exit(1);
 #undef PUTC
 }