From 11cb66c391be342548ce819897cf17f573babc00 Mon Sep 17 00:00:00 2001
From: Brooks Davis <brooks@one-eyed-alien.net>
Date: Tue, 10 Feb 2015 17:43:10 +0000
Subject: [PATCH] Add a new tar option --clear-nochange-fflags that causes file
 system flags which might prevent the removal or modifiction of files to be
 cleared before attempting to remove them.

Sponsored by: DARPA, AFRL
---
 tar/bsdtar.1  | 4 ++++
 tar/bsdtar.c  | 4 ++++
 tar/bsdtar.h  | 1 +
 tar/cmdline.c | 1 +
 4 files changed, 10 insertions(+)

diff --git a/tar/bsdtar.1 b/tar/bsdtar.1
index 09402400f..9e45f191d 100644
--- a/tar/bsdtar.1
+++ b/tar/bsdtar.1
@@ -184,6 +184,10 @@ but before extracting entries from the archive.
 to the current directory after processing any
 .Fl C
 options and before extracting any files.
+.It Fl Fl clear-nochange-fflags
+(x mode only)
+Before removing file system objects to replace them, clear platform-specific
+file flags that might prevent removal.
 .It Fl Fl disable-copyfile
 Mac OS X specific.
 Disable the use of
diff --git a/tar/bsdtar.c b/tar/bsdtar.c
index a8c846b0c..93bf60a94 100644
--- a/tar/bsdtar.c
+++ b/tar/bsdtar.c
@@ -290,6 +290,10 @@ main(int argc, char **argv)
 		case OPTION_CHROOT: /* NetBSD */
 			bsdtar->option_chroot = 1;
 			break;
+		case OPTION_CLEAR_NOCHANGE_FFLAGS:
+			bsdtar->extract_flags |=
+			    ARCHIVE_EXTRACT_CLEAR_NOCHANGE_FFLAGS;
+			break;
 		case OPTION_DISABLE_COPYFILE: /* Mac OS X */
 			bsdtar->readdisk_flags &= ~ARCHIVE_READDISK_MAC_COPYFILE;
 			break;
diff --git a/tar/bsdtar.h b/tar/bsdtar.h
index 8e64b0a79..c05bfe888 100644
--- a/tar/bsdtar.h
+++ b/tar/bsdtar.h
@@ -119,6 +119,7 @@ enum {
 	OPTION_B64ENCODE = 1,
 	OPTION_CHECK_LINKS,
 	OPTION_CHROOT,
+	OPTION_CLEAR_NOCHANGE_FFLAGS,
 	OPTION_DISABLE_COPYFILE,
 	OPTION_EXCLUDE,
 	OPTION_FORMAT,
diff --git a/tar/cmdline.c b/tar/cmdline.c
index bb905812d..fd0712a0d 100644
--- a/tar/cmdline.c
+++ b/tar/cmdline.c
@@ -74,6 +74,7 @@ static const struct bsdtar_option {
 	{ "cd",                   1, 'C' },
 	{ "check-links",          0, OPTION_CHECK_LINKS },
 	{ "chroot",               0, OPTION_CHROOT },
+	{ "clear-nochange-fflags", 0, OPTION_CLEAR_NOCHANGE_FFLAGS },
 	{ "compress",             0, 'Z' },
 	{ "confirmation",         0, 'w' },
 	{ "create",               0, 'c' },
-- 
2.47.2