diff --git a/libc/bionic/fts.c b/libc/bionic/fts.c
index 8888ab1..34de992 100644
--- a/libc/bionic/fts.c
+++ b/libc/bionic/fts.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: fts.c,v 1.48 2014/11/20 04:14:15 guenther Exp $	*/
+/*	$OpenBSD: fts.c,v 1.60 2021/01/08 16:06:30 tb Exp $	*/
 
 /*-
  * Copyright (c) 1990, 1993, 1994
@@ -29,10 +29,9 @@
  * SUCH DAMAGE.
  */
 
-#include <sys/param.h>
+#include <sys/param.h>	/* ALIGN */
 #include <sys/stat.h>
 
-#include <assert.h>
 #include <dirent.h>
 #include <errno.h>
 #include <fcntl.h>
@@ -42,7 +41,9 @@
 #include <string.h>
 #include <unistd.h>
 
-static FTSENT	*fts_alloc(FTS *, char *, size_t);
+#define MAXIMUM(a, b)	(((a) > (b)) ? (a) : (b))
+
+static FTSENT	*fts_alloc(FTS *, const char *, size_t);
 static FTSENT	*fts_build(FTS *, int);
 static void	 fts_lfree(FTSENT *);
 static void	 fts_load(FTS *, FTSENT *);
@@ -51,11 +52,13 @@
 static int	 fts_palloc(FTS *, size_t);
 static FTSENT	*fts_sort(FTS *, FTSENT *, int);
 static u_short	 fts_stat(FTS *, FTSENT *, int, int);
-static int	 fts_safe_changedir(FTS *, FTSENT *, int, char *);
+static int	 fts_safe_changedir(FTS *, FTSENT *, int, const char *);
 
+#define DEF_WEAK(s) /* nothing */
 #define ALIGNBYTES (sizeof(uintptr_t) - 1)
 #define ALIGN(p) (((uintptr_t)(p) + ALIGNBYTES) &~ ALIGNBYTES)
 void* reallocarray(void*, size_t, size_t);
+void* recallocarray(void*, size_t, size_t, size_t);
 
 #define	ISDOT(a)	(a[0] == '.' && (!a[1] || (a[1] == '.' && !a[2])))
 
@@ -70,12 +73,22 @@
 #define	BNAMES		2		/* fts_children, names only */
 #define	BREAD		3		/* fts_read */
 
-FTS* __fts_open(char* const* argv, int options, int (*compar)(const FTSENT**, const FTSENT**)) {
+FTS *
+__fts_open(char * const *argv, int options,
+    int (*compar)(const FTSENT **, const FTSENT **))
+{
 	FTS *sp;
 	FTSENT *p, *root;
 	int nitems;
-	FTSENT *parent, *tmp;
-	size_t len;
+	FTSENT *parent, *prev;
+
+	/* Android: options check moved to __fts_open() for ftw(). */
+
+	/* At least one path must be specified. */
+	if (*argv == NULL) {
+		errno = EINVAL;
+		return (NULL);
+	}
 
 	/* Allocate/initialize the stream */
 	if ((sp = calloc(1, sizeof(FTS))) == NULL)
@@ -91,7 +104,7 @@
 	 * Start out with 1K of path space, and enough, in any case,
 	 * to hold the user's paths.
 	 */
-	if (fts_palloc(sp, MAX(fts_maxarglen(argv), PATH_MAX)))
+	if (fts_palloc(sp, MAXIMUM(fts_maxarglen(argv), PATH_MAX)))
 		goto mem1;
 
 	/* Allocate/initialize root's parent. */
@@ -100,21 +113,15 @@
 	parent->fts_level = FTS_ROOTPARENTLEVEL;
 
 	/* Allocate/initialize root(s). */
-	for (root = NULL, nitems = 0; *argv; ++argv, ++nitems) {
-		/* Don't allow zero-length paths. */
-		if ((len = strlen(*argv)) == 0) {
-			errno = ENOENT;
-			goto mem3;
-		}
-
-		if ((p = fts_alloc(sp, *argv, len)) == NULL)
+	for (root = prev = NULL, nitems = 0; *argv; ++argv, ++nitems) {
+		if ((p = fts_alloc(sp, *argv, strlen(*argv))) == NULL)
 			goto mem3;
 		p->fts_level = FTS_ROOTLEVEL;
 		p->fts_parent = parent;
 		p->fts_accpath = p->fts_name;
 		p->fts_info = fts_stat(sp, p, ISSET(FTS_COMFOLLOW), -1);
 
-		// For ftw/nftw we need to fail early: http://b/31152735
+		// Android: for ftw/nftw we need to fail early: http://b/31152735
 		if ((options & FTS_FOR_FTW) != 0 && p->fts_info == FTS_NS) goto mem3;
 
 		/* Command-line "." and ".." are real directories. */
@@ -131,11 +138,10 @@
 		} else {
 			p->fts_link = NULL;
 			if (root == NULL)
-				tmp = root = p;
-			else {
-				tmp->fts_link = p;
-				tmp = p;
-			}
+				root = p;
+			else
+				prev->fts_link = p;
+			prev = p;
 		}
 	}
 	if (compar && nitems > 1)
@@ -158,7 +164,8 @@
 	 * and ".." are all fairly nasty problems.  Note, if we can't get the
 	 * descriptor we run anyway, just more slowly.
 	 */
-	if (!ISSET(FTS_NOCHDIR) && (sp->fts_rfd = open(".", O_RDONLY|O_CLOEXEC, 0)) < 0)
+	if (!ISSET(FTS_NOCHDIR) &&
+	    (sp->fts_rfd = open(".", O_RDONLY | O_CLOEXEC)) == -1)
 		SET(FTS_NOCHDIR);
 
 	if (nitems == 0)
@@ -172,6 +179,7 @@
 mem1:	free(sp);
 	return (NULL);
 }
+DEF_WEAK(fts_open);
 
 static void
 fts_load(FTS *sp, FTSENT *p)
@@ -221,7 +229,8 @@
 	rfd = ISSET(FTS_NOCHDIR) ? -1 : sp->fts_rfd;
 
 	/* Free up child linked list, sort array, path buffer, stream ptr.*/
-	fts_lfree(sp->fts_child);
+	if (sp->fts_child)
+		fts_lfree(sp->fts_child);
 	free(sp->fts_array);
 	free(sp->fts_path);
 	free(sp);
@@ -237,6 +246,7 @@
 
 	return (error);
 }
+DEF_WEAK(fts_close);
 
 /*
  * Special case of "/" at the end of the path so that slashes aren't
@@ -281,7 +291,8 @@
 	    (p->fts_info == FTS_SL || p->fts_info == FTS_SLNONE)) {
 		p->fts_info = fts_stat(sp, p, 1, -1);
 		if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
-			if ((p->fts_symfd = open(".", O_RDONLY|O_CLOEXEC, 0)) < 0) {
+			if ((p->fts_symfd =
+			    open(".", O_RDONLY | O_CLOEXEC)) == -1) {
 				p->fts_errno = errno;
 				p->fts_info = FTS_ERR;
 			} else
@@ -370,7 +381,8 @@
 		if (p->fts_instr == FTS_FOLLOW) {
 			p->fts_info = fts_stat(sp, p, 1, -1);
 			if (p->fts_info == FTS_D && !ISSET(FTS_NOCHDIR)) {
-				if ((p->fts_symfd = open(".", O_RDONLY|O_CLOEXEC, 0)) < 0) {
+				if ((p->fts_symfd =
+				    open(".", O_RDONLY | O_CLOEXEC)) == -1) {
 					p->fts_errno = errno;
 					p->fts_info = FTS_ERR;
 				} else
@@ -432,6 +444,7 @@
 	p->fts_info = p->fts_errno ? FTS_ERR : FTS_DP;
 	return (sp->fts_cur = p);
 }
+DEF_WEAK(fts_read);
 
 /*
  * Fts_set takes the stream as an argument although it's not used in this
@@ -439,7 +452,6 @@
  * semantics to fts using fts_set.  An error return is allowed for similar
  * reasons.
  */
-/* ARGSUSED */
 int
 fts_set(FTS *sp __unused, FTSENT *p, int instr)
 {
@@ -451,6 +463,7 @@
 	p->fts_instr = instr;
 	return (0);
 }
+DEF_WEAK(fts_set);
 
 FTSENT *
 fts_children(FTS *sp, int instr)
@@ -489,7 +502,8 @@
 		return (NULL);
 
 	/* Free up any previous child list. */
-	fts_lfree(sp->fts_child);
+	if (sp->fts_child)
+		fts_lfree(sp->fts_child);
 
 	if (instr == FTS_NAMEONLY) {
 		SET(FTS_NAMEONLY);
@@ -508,7 +522,7 @@
 	    ISSET(FTS_NOCHDIR))
 		return (sp->fts_child = fts_build(sp, instr));
 
-	if ((fd = open(".", O_RDONLY|O_CLOEXEC, 0)) < 0)
+	if ((fd = open(".", O_RDONLY | O_CLOEXEC)) == -1)
 		return (NULL);
 	sp->fts_child = fts_build(sp, instr);
 	if (fchdir(fd)) {
@@ -518,6 +532,7 @@
 	(void)close(fd);
 	return (sp->fts_child);
 }
+DEF_WEAK(fts_children);
 
 /*
  * This is the tricky part -- do not casually change *anything* in here.  The
@@ -542,9 +557,9 @@
 	DIR *dirp;
 	void *oldaddr;
 	size_t len, maxlen;
-	int nitems, cderrno, descend, level, nlinks, nostat = 0, doadjust;
+	int nitems, cderrno, descend, level, nlinks, nostat, doadjust;
 	int saved_errno;
-	char *cp = NULL;
+	char *cp;
 
 	/* Set current node pointer. */
 	cur = sp->fts_cur;
@@ -709,8 +724,7 @@
 			/* Build a file name for fts_stat to stat. */
 			if (ISSET(FTS_NOCHDIR)) {
 				p->fts_accpath = p->fts_path;
-				assert(cp && "cp should be non-null if FTS_NOCHDIR is set");
-				memmove(cp, p->fts_name, p->fts_namelen + 1); // NOLINT
+				memmove(cp, p->fts_name, p->fts_namelen + 1);
 				p->fts_info = fts_stat(sp, p, 0, dirfd(dirp));
 			} else {
 				p->fts_accpath = p->fts_name;
@@ -806,9 +820,9 @@
 	 * fail, set the errno from the stat call.
 	 */
 	if (ISSET(FTS_LOGICAL) || follow) {
-		if (fstatat(dfd, path, sbp, 0) == -1) {
+		if (fstatat(dfd, path, sbp, 0)) {
 			saved_errno = errno;
-			if (fstatat(dfd, path, sbp, AT_SYMLINK_NOFOLLOW) == 0) {
+			if (!fstatat(dfd, path, sbp, AT_SYMLINK_NOFOLLOW)) {
 				errno = 0;
 				return (FTS_SLNONE);
 			}
@@ -872,19 +886,19 @@
 	if (nitems > sp->fts_nitems) {
 		struct _ftsent **a;
 
-		sp->fts_nitems = nitems + 40;
 		if ((a = reallocarray(sp->fts_array,
-		    sp->fts_nitems, sizeof(FTSENT *))) == NULL) {
+		    nitems + 40, sizeof(FTSENT *))) == NULL) {
 			free(sp->fts_array);
 			sp->fts_array = NULL;
 			sp->fts_nitems = 0;
 			return (head);
 		}
+		sp->fts_nitems = nitems + 40;
 		sp->fts_array = a;
 	}
 	for (ap = sp->fts_array, p = head; p; p = p->fts_link)
 		*ap++ = p;
-	qsort((void *)sp->fts_array, nitems, sizeof(FTSENT *), sp->fts_compar);
+	qsort(sp->fts_array, nitems, sizeof(FTSENT *), sp->fts_compar);
 	for (head = *(ap = sp->fts_array); --nitems; ++ap)
 		ap[0]->fts_link = ap[1];
 	ap[0]->fts_link = NULL;
@@ -892,7 +906,7 @@
 }
 
 static FTSENT *
-fts_alloc(FTS *sp, char *name, size_t namelen)
+fts_alloc(FTS *sp, const char *name, size_t namelen)
 {
 	FTSENT *p;
 	size_t len;
@@ -954,13 +968,14 @@
 		errno = ENAMETOOLONG;
 		return (1);
 	}
-	sp->fts_pathlen += more;
-	p = realloc(sp->fts_path, sp->fts_pathlen);
+	p = recallocarray(sp->fts_path, sp->fts_pathlen,
+	    sp->fts_pathlen + more, 1);
 	if (p == NULL) {
 		free(sp->fts_path);
 		sp->fts_path = NULL;
 		return (1);
 	}
+	sp->fts_pathlen += more;
 	sp->fts_path = p;
 	return (0);
 }
@@ -1010,7 +1025,7 @@
  * Assumes p->fts_dev and p->fts_ino are filled in.
  */
 static int
-fts_safe_changedir(FTS *sp, FTSENT *p, int fd, char *path)
+fts_safe_changedir(FTS *sp, FTSENT *p, int fd, const char *path)
 {
 	int ret, oerrno, newfd;
 	struct stat sb;
@@ -1018,9 +1033,9 @@
 	newfd = fd;
 	if (ISSET(FTS_NOCHDIR))
 		return (0);
-	if (fd < 0 && (newfd = open(path, O_RDONLY|O_DIRECTORY|O_CLOEXEC, 0)) < 0)
+	if (fd == -1 && (newfd = open(path, O_RDONLY|O_DIRECTORY|O_CLOEXEC)) == -1)
 		return (-1);
-	if (fstat(newfd, &sb)) {
+	if (fstat(newfd, &sb) == -1) {
 		ret = -1;
 		goto bail;
 	}
@@ -1032,17 +1047,21 @@
 	ret = fchdir(newfd);
 bail:
 	oerrno = errno;
-	if (fd < 0)
+	if (fd == -1)
 		(void)close(newfd);
 	errno = oerrno;
 	return (ret);
 }
 
-FTS* fts_open(char* const* argv, int options, int (*compar)(const FTSENT**, const FTSENT**)) {
-    // Options check.
-    if ((options & ~FTS_OPTIONMASK) != 0) {
-        errno = EINVAL;
-        return NULL;
-    }
-    return __fts_open(argv, options, compar);
+FTS *
+fts_open(char * const *argv, int options,
+    int (*compar)(const FTSENT **, const FTSENT **))
+{
+	// Android needs to an __fts_open() that doesn't make this check
+	// so that FTS_FOR_FTW works.
+	if (options & ~FTS_OPTIONMASK) {
+		errno = EINVAL;
+		return (NULL);
+	}
+	return __fts_open(argv, options, compar);
 }