libc: revert inadvertent removal of O_CLOEXEC #ifndefs

Change-Id: I15005181388280363f7aee546bd2ecc0cd5b37e6

lib/libc/db/recno/rec_open.c

@@ -70,8 +70,15 @@ __rec_open(const char *fname, int flags, mode_t mode, const RECNOINFO *openinfo,
 	dbp = NULL;
 	/* Open the user's file -- if this fails, we're done. */
 	if (fname != NULL) {
+#ifndef O_CLOEXEC
+#define O_CLOEXEC 0
+#endif
 		if ((rfd = open(fname, flags | O_CLOEXEC, mode)) == -1)
 			return NULL;
+#if O_CLOEXEC == 0
+		if (fcntl(rfd, F_SETFD, FD_CLOEXEC) == -1)
+			goto err;
+#endif
 	}
 
 	/* Create a btree in memory (backed by disk). */

lib/libc/gen/fts.c

@@ -213,6 +213,9 @@ fts_open(char * const *argv, int options,
 	 * and ".." are all fairly nasty problems.  Note, if we can't get the
 	 * descriptor we run anyway, just more slowly.
 	 */
+#ifndef O_CLOEXEC
+#define O_CLOEXEC 0
+#endif
 	if (!ISSET(FTS_NOCHDIR)) {
 		if ((sp->fts_rfd = open(".", O_RDONLY | O_CLOEXEC, 0)) == -1)
 			SET(FTS_NOCHDIR);

lib/libc/gen/initdir.c

@@ -42,6 +42,10 @@ __RCSID("$NetBSD: initdir.c,v 1.3 2012/03/13 21:13:36 christos Exp $");
 #include <sys/featuretest.h>
 #include <sys/types.h>
 
+#ifndef O_CLOEXEC
+#define O_CLOEXEC 0
+#endif
+
 #endif
 
 #include "reentrant.h"