introduce and use close_on_exec_on(fd). -50 bytes.

include/libbb.h

@@ -248,6 +248,7 @@ extern char *bb_get_last_path_component_nostrip(const char *path);
 
 int ndelay_on(int fd);
 int ndelay_off(int fd);
+int close_on_exec_on(int fd);
 void xdup2(int, int);
 void xmove_fd(int, int);
 

init/init.c

@@ -179,7 +179,7 @@ static void message(int device, const char *fmt, ...)
 				bb_error_msg("can't log to %s", log_console);
 				device = L_CONSOLE;
 			} else {
-				fcntl(log_fd, F_SETFD, FD_CLOEXEC);
+				close_on_exec_on(log_fd);
 			}
 		}
 	}

libbb/xfuncs.c

@@ -164,6 +164,11 @@ int ndelay_on(int fd)
 	return fcntl(fd, F_SETFL, fcntl(fd,F_GETFL) | O_NONBLOCK);
 }
 
+int close_on_exec_on(int fd)
+{
+        return fcntl(fd, F_SETFD, FD_CLOEXEC);
+}
+
 int ndelay_off(int fd)
 {
 	return fcntl(fd, F_SETFL, fcntl(fd,F_GETFL) & ~O_NONBLOCK);

miscutils/devfsd.c

@@ -371,10 +371,7 @@ int devfsd_main(int argc, char **argv)
 	xchdir(mount_point);
 
 	fd = xopen(".devfsd", O_RDONLY);
-
+	close_on_exec_on(fd);
-	if (fcntl(fd, F_SETFD, FD_CLOEXEC) != 0)
-		bb_perror_msg_and_die("FD_CLOEXEC");
-
 	xioctl(fd, DEVFSDIOC_GET_PROTO_REV, &proto_rev);
 
 	/*setup initial entries */

networking/nc.c

@@ -113,7 +113,7 @@ int nc_main(int argc, char **argv)
 				lport = get_nport(&lsa->sa);
 				fdprintf(2, "%d\n", ntohs(lport));
 			}
-			fcntl(sfd, F_SETFD, FD_CLOEXEC);
+			close_on_exec_on(sfd);
  accept_again:
 			cfd = accept(sfd, NULL, 0);
 			if (cfd < 0)

networking/udhcp/signalpipe.c

@@ -39,9 +39,9 @@ void udhcp_sp_setup(void)
 {
 	/* was socketpair, but it needs AF_UNIX in kernel */
 	xpipe(signal_pipe);
-	fcntl(signal_pipe[0], F_SETFD, FD_CLOEXEC);
+	close_on_exec_on(signal_pipe[0]);
-	fcntl(signal_pipe[1], F_SETFD, FD_CLOEXEC);
+	close_on_exec_on(signal_pipe[1]);
-	fcntl(signal_pipe[1], F_SETFL, O_NONBLOCK);
+	ndelay_on(signal_pipe[1]);
 	signal(SIGUSR1, signal_handler);
 	signal(SIGUSR2, signal_handler);
 	signal(SIGTERM, signal_handler);
@@ -56,7 +56,7 @@ int udhcp_sp_fd_set(fd_set *rfds, int extra_fd)
 	FD_ZERO(rfds);
 	FD_SET(signal_pipe[0], rfds);
 	if (extra_fd >= 0) {
-		fcntl(extra_fd, F_SETFD, FD_CLOEXEC);
+		close_on_exec_on(extra_fd);
 		FD_SET(extra_fd, rfds);
 	}
 	return signal_pipe[0] > extra_fd ? signal_pipe[0] : extra_fd;

runit/runit_lib.c

@@ -50,11 +50,6 @@ unsigned byte_chr(char *s,unsigned n,int c)
 	return t - s;
 }
 
-int coe(int fd)
-{
-	return fcntl(fd, F_SETFD, FD_CLOEXEC);
-}
-
 #ifdef UNUSED
 static /* as it isn't used anywhere else */
 void tai_pack(char *s, const struct tai *t)

runit/runit_lib.h

@@ -27,8 +27,6 @@ ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 extern unsigned byte_chr(char *s,unsigned n,int c);
 
-extern int coe(int);
-
 #define direntry struct dirent
 
 //struct tai {

runit/runsv.c

@@ -454,8 +454,8 @@ int runsv_main(int argc, char **argv)
 	dir = argv[1];
 
 	xpipe(selfpipe);
-	coe(selfpipe[0]);
+	close_on_exec_on(selfpipe[0]);
-	coe(selfpipe[1]);
+	close_on_exec_on(selfpipe[1]);
 	ndelay_on(selfpipe[0]);
 	ndelay_on(selfpipe[1]);
 
@@ -491,8 +491,8 @@ int runsv_main(int argc, char **argv)
 			if (stat("log/down", &s) != -1)
 				svd[1].want = W_DOWN;
 			xpipe(logpipe);
-			coe(logpipe[0]);
+			close_on_exec_on(logpipe[0]);
-			coe(logpipe[1]);
+			close_on_exec_on(logpipe[1]);
 		}
 	}
 
@@ -512,7 +512,7 @@ int runsv_main(int argc, char **argv)
 			O_WRONLY|O_NDELAY|O_APPEND|O_CREAT, 0600);
 	if (lock_exnb(svd[0].fdlock) == -1)
 		fatal_cannot("lock supervise/lock");
-	coe(svd[0].fdlock);
+	close_on_exec_on(svd[0].fdlock);
 	if (haslog) {
 		if (mkdir("log/supervise", 0700) == -1) {
 			r = readlink("log/supervise", buf, 256);
@@ -536,30 +536,30 @@ int runsv_main(int argc, char **argv)
 				O_WRONLY|O_NDELAY|O_APPEND|O_CREAT, 0600);
 		if (lock_ex(svd[1].fdlock) == -1)
 			fatal_cannot("lock log/supervise/lock");
-		coe(svd[1].fdlock);
+		close_on_exec_on(svd[1].fdlock);
 	}
 
 	mkfifo("log/supervise/control"+4, 0600);
 	svd[0].fdcontrol = xopen("log/supervise/control"+4, O_RDONLY|O_NDELAY);
-	coe(svd[0].fdcontrol);
+	close_on_exec_on(svd[0].fdcontrol);
 	svd[0].fdcontrolwrite = xopen("log/supervise/control"+4, O_WRONLY|O_NDELAY);
-	coe(svd[0].fdcontrolwrite);
+	close_on_exec_on(svd[0].fdcontrolwrite);
 	update_status(&svd[0]);
 	if (haslog) {
 		mkfifo("log/supervise/control", 0600);
 		svd[1].fdcontrol = xopen("log/supervise/control", O_RDONLY|O_NDELAY);
-		coe(svd[1].fdcontrol);
+		close_on_exec_on(svd[1].fdcontrol);
 		svd[1].fdcontrolwrite = xopen("log/supervise/control", O_WRONLY|O_NDELAY);
-		coe(svd[1].fdcontrolwrite);
+		close_on_exec_on(svd[1].fdcontrolwrite);
 		update_status(&svd[1]);
 	}
 	mkfifo("log/supervise/ok"+4, 0600);
 	fd = xopen("log/supervise/ok"+4, O_RDONLY|O_NDELAY);
-	coe(fd);
+	close_on_exec_on(fd);
 	if (haslog) {
 		mkfifo("log/supervise/ok", 0600);
 		fd = xopen("log/supervise/ok", O_RDONLY|O_NDELAY);
-		coe(fd);
+		close_on_exec_on(fd);
 	}
 	for (;;) {
 		struct pollfd x[3];

runit/runsvdir.c

@@ -190,8 +190,8 @@ static int setup_log(void)
 		warnx("cannot create pipe for log");
 		return -1;
 	}
-	coe(logpipe[1]);
+	close_on_exec_on(logpipe[1]);
-	coe(logpipe[0]);
+	close_on_exec_on(logpipe[0]);
 	ndelay_on(logpipe[0]);
 	ndelay_on(logpipe[1]);
 	if (dup2(logpipe[1], 2) == -1) {
@@ -245,7 +245,7 @@ int runsvdir_main(int argc, char **argv)
 	curdir = open_read(".");
 	if (curdir == -1)
 		fatal2_cannot("open current directory", "");
-	coe(curdir);
+	close_on_exec_on(curdir);
 
 	stampcheck = monotonic_sec();
 

runit/svlogd.c

@@ -361,7 +361,7 @@ static unsigned rotate(struct logdir *ld)
 		/* we presume this cannot fail */
 		ld->filecur = fdopen(ld->fdcur, "a"); ////
 		setvbuf(ld->filecur, NULL, _IOFBF, linelen); ////
-		coe(ld->fdcur);
+		close_on_exec_on(ld->fdcur);
 		ld->size = 0;
 		while (fchmod(ld->fdcur, 0644) == -1)
 			pause2cannot("set mode of current", ld->name);
@@ -482,7 +482,7 @@ static unsigned logdir_open(struct logdir *ld, const char *fn)
 		warn2("cannot open log directory", (char*)fn);
 		return 0;
 	}
-	coe(ld->fddir);
+	close_on_exec_on(ld->fddir);
 	if (fchdir(ld->fddir) == -1) {
 		logdir_close(ld);
 		warn2("cannot change directory", (char*)fn);
@@ -498,7 +498,7 @@ static unsigned logdir_open(struct logdir *ld, const char *fn)
 			pause1cannot("change to initial working directory");
 		return 0;
 	}
-	coe(ld->fdlock);
+	close_on_exec_on(ld->fdlock);
 
 	ld->size = 0;
 	ld->sizemax = 1000000;
@@ -624,7 +624,7 @@ static unsigned logdir_open(struct logdir *ld, const char *fn)
 	ld->filecur = fdopen(ld->fdcur, "a"); ////
 	setvbuf(ld->filecur, NULL, _IOFBF, linelen); ////
 
-	coe(ld->fdcur);
+	close_on_exec_on(ld->fdcur);
 	while (fchmod(ld->fdcur, 0644) == -1)
 		pause2cannot("set mode of current", ld->name);
 
@@ -851,7 +851,7 @@ int svlogd_main(int argc, char **argv)
 	if (dirn <= 0) usage();
 	////if (buflen <= linemax) usage();
 	fdwdir = xopen(".", O_RDONLY|O_NDELAY);
-	coe(fdwdir);
+	close_on_exec_on(fdwdir);
 	dir = xzalloc(dirn * sizeof(struct logdir));
 	for (i = 0; i < dirn; ++i) {
 		dir[i].fddir = -1;

shell/ash.c

@@ -3469,7 +3469,7 @@ setjobctl(int on)
 		close(ofd);
 		if (fd < 0)
 			goto out;
-		fcntl(fd, F_SETFD, FD_CLOEXEC);
+		close_on_exec_on(fd);
 		do { /* while we are in the background */
 			pgrp = tcgetpgrp(fd);
 			if (pgrp < 0) {
@@ -8830,7 +8830,7 @@ closescript(void)
 static void
 setinputfd(int fd, int push)
 {
-	fcntl(fd, F_SETFD, FD_CLOEXEC);
+	close_on_exec_on(fd);
 	if (push) {
 		pushfile();
 		parsefile->buf = 0;

shell/hush.c

@@ -760,9 +760,11 @@ static int builtin_eval(char **argv)
 static int builtin_cd(char **argv)
 {
 	const char *newdir;
-	if (argv[1] == NULL)
+	if (argv[1] == NULL) {
+		// bash does nothing (exitcode 0) if HOME is ""; if it's unset,
+		// bash says "bash: cd: HOME not set" and does nothing (exitcode 1)
 		newdir = getenv("HOME") ? : "/";
-	else
+	} else
 		newdir = argv[1];
 	if (chdir(newdir)) {
 		printf("cd: %s: %s\n", newdir, strerror(errno));
@@ -3629,7 +3631,7 @@ static void setup_job_control(void)
 
 	saved_task_pgrp = shell_pgrp = getpgrp();
 	debug_printf_jobs("saved_task_pgrp=%d\n", saved_task_pgrp);
-	fcntl(interactive_fd, F_SETFD, FD_CLOEXEC);
+	close_on_exec_on(interactive_fd);
 
 	/* If we were ran as 'hush &',
 	 * sleep until we are in the foreground.  */

shell/lash.c

@@ -576,7 +576,7 @@ static int setup_redirects(struct child_prog *prog, int squirrel[])
 		if (openfd != redir->fd) {
 			if (squirrel && redir->fd < 3) {
 				squirrel[redir->fd] = dup(redir->fd);
-				fcntl(squirrel[redir->fd], F_SETFD, FD_CLOEXEC);
+				close_on_exec_on(squirrel[redir->fd]);
 			}
 			dup2(openfd, redir->fd);
 			close(openfd);