bsdtar: Support --mtime and --clamp-mtime (#2601)

Hi, This PR adds support for setting a forced mtime on all written files (`--mtime` and `--clamp-mtime`) in bsdtar. The end goal will be to support all functionalities in <https://reproducible-builds.org/docs/archives/#full-example>, namely `--sort` and disabling other attributes (atime, ctime, etc.). Fixes #971. ## History - [v1](https://github.com/zhaofengli/libarchive/tree/forced-mtime-v1): Added `archive_read_disk_set_forced_mtime` in libarchive. As a result, it was only applied when reading from the filesystem and not from other archives. - [v2](https://github.com/zhaofengli/libarchive/tree/forced-mtime-v2): Refactored to apply the forced mtime in `archive_write`. - v3 (current): Reduced libarchive change to exposing `archive_parse_date`, moved clamping logic into bsdtar. --------- Signed-off-by: Zhaofeng Li <hello@zhaofeng.li> Co-authored-by: Dustin L. Howett <dustin@howett.net>
2026-01-18 17:11:25 +01:00 · 2025-05-15 06:08:14 -06:00
parent 84ac71335f
commit c26f037745
19 changed files with 187 additions and 92 deletions
--- a/2
+++ b/2
@@ -20,7 +20,7 @@ the actual statements in the files are controlling.
   libarchive/mtree.5

 * The following source files are in the public domain:
-   libarchive/archive_getdate.c
+   libarchive/archive_parse_date.c

 * The following source files are triple-licensed with the ability to choose
  from CC0 1.0 Universal, OpenSSL or Apache 2.0 licenses:
--- a/Makefile.am
+++ b/Makefile.am
@@ -118,8 +118,6 @@ libarchive_la_SOURCES= \
 	libarchive/archive_entry_stat.c \
 	libarchive/archive_entry_strmode.c \
 	libarchive/archive_entry_xattr.c \
-	libarchive/archive_getdate.c \
-	libarchive/archive_getdate.h \
 	libarchive/archive_hmac.c \
 	libarchive/archive_hmac_private.h \
 	libarchive/archive_match.c \
@@ -129,6 +127,7 @@ libarchive_la_SOURCES= \
 	libarchive/archive_options_private.h \
 	libarchive/archive_pack_dev.h \
 	libarchive/archive_pack_dev.c \
+	libarchive/archive_parse_date.c \
 	libarchive/archive_pathmatch.c \
 	libarchive/archive_pathmatch.h \
 	libarchive/archive_platform.h \
@@ -379,10 +378,10 @@ libarchive_test_SOURCES= \
 	libarchive/test/test_archive_clear_error.c \
 	libarchive/test/test_archive_cmdline.c \
 	libarchive/test/test_archive_digest.c \
-	libarchive/test/test_archive_getdate.c \
 	libarchive/test/test_archive_match_owner.c \
 	libarchive/test/test_archive_match_path.c \
 	libarchive/test/test_archive_match_time.c \
+	libarchive/test/test_archive_parse_date.c \
 	libarchive/test/test_archive_pathmatch.c \
 	libarchive/test/test_archive_read.c \
 	libarchive/test/test_archive_read_add_passphrase.c \
@@ -1178,6 +1177,7 @@ bsdtar_test_SOURCES= \
 	tar/test/test_option_lz4.c \
 	tar/test/test_option_lzma.c \
 	tar/test/test_option_lzop.c \
+	tar/test/test_option_mtime.c \
 	tar/test/test_option_n.c \
 	tar/test/test_option_newer_than.c \
 	tar/test/test_option_nodump.c \
--- a/contrib/android/Android.mk
+++ b/contrib/android/Android.mk
@@ -37,11 +37,11 @@ libarchive_src_files := libarchive/archive_acl.c \
 						libarchive/archive_entry_stat.c \
 						libarchive/archive_entry_strmode.c \
 						libarchive/archive_entry_xattr.c \
-						libarchive/archive_getdate.c \
 						libarchive/archive_hmac.c \
 						libarchive/archive_match.c \
 						libarchive/archive_options.c \
 						libarchive/archive_pack_dev.c \
+						libarchive/archive_parse_date.c \
 						libarchive/archive_pathmatch.c \
 						libarchive/archive_ppmd7.c \
 						libarchive/archive_random.c \
--- a/libarchive/CMakeLists.txt
+++ b/libarchive/CMakeLists.txt
@@ -38,8 +38,6 @@ SET(libarchive_SOURCES
  archive_entry_stat.c
  archive_entry_strmode.c
  archive_entry_xattr.c
-  archive_getdate.c
-  archive_getdate.h
  archive_hmac.c
  archive_hmac_private.h
  archive_match.c
@@ -49,6 +47,7 @@ SET(libarchive_SOURCES
  archive_options_private.h
  archive_pack_dev.h
  archive_pack_dev.c
+  archive_parse_date.c
  archive_pathmatch.c
  archive_pathmatch.h
  archive_platform.h
--- a/libarchive/archive.h
+++ b/libarchive/archive.h
@@ -1128,6 +1128,10 @@ __LA_DECL int		 archive_compression(struct archive *)
 				__LA_DEPRECATED;
 #endif

+/* Parses a date string relative to the current time.
+ * NOTE: This is not intended for general date parsing, and the resulting timestamp should only be used for libarchive. */
+__LA_DECL time_t	archive_parse_date(time_t now, const char *datestr);
+
 __LA_DECL int		 archive_errno(struct archive *);
 __LA_DECL const char	*archive_error_string(struct archive *);
 __LA_DECL const char	*archive_format_name(struct archive *);
--- a/libarchive/archive_getdate.h
+++ b/libarchive/archive_getdate.h
@@ -1,37 +0,0 @@
-/*-
- * Copyright (c) 2003-2015 Tim Kientzle
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
- * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
- * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
- * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
- * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
-#ifndef ARCHIVE_GETDATE_H_INCLUDED
-#define ARCHIVE_GETDATE_H_INCLUDED
-
-#ifndef __LIBARCHIVE_BUILD
-#error This header is only to be used internally to libarchive.
-#endif
-
-#include <time.h>
-
-time_t __archive_get_date(time_t now, const char *);
-
-#endif
--- a/libarchive/archive_match.c
+++ b/libarchive/archive_match.c
@@ -39,7 +39,6 @@
 #include "archive.h"
 #include "archive_private.h"
 #include "archive_entry.h"
-#include "archive_getdate.h"
 #include "archive_pathmatch.h"
 #include "archive_rb.h"
 #include "archive_string.h"
@@ -188,7 +187,7 @@ static int	time_excluded(struct archive_match *,
 		    struct archive_entry *);
 static int	validate_time_flag(struct archive *, int, const char *);

-#define get_date __archive_get_date
+#define get_date archive_parse_date

 static const struct archive_rb_tree_ops rb_ops_mbs = {
 	cmp_node_mbs, cmp_key_mbs
--- a/libarchive/archive_parse_date.c
+++ b/libarchive/archive_parse_date.c
@@ -35,8 +35,7 @@
 #include <string.h>
 #include <time.h>

-#define __LIBARCHIVE_BUILD 1
-#include "archive_getdate.h"
+#include "archive.h"

 /* Basic time units. */
 #define	EPOCH		1970
@@ -937,7 +936,7 @@ difftm (struct tm *a, struct tm *b)
 * TODO: tokens[] array should be dynamically sized.
 */
 time_t
-__archive_get_date(time_t now, const char *p)
+archive_parse_date(time_t now, const char *p)
 {
 	struct token	tokens[256];
 	struct gdstate	_gds;
--- a/libarchive/test/CMakeLists.txt
+++ b/libarchive/test/CMakeLists.txt
@@ -21,10 +21,10 @@ IF(ENABLE_TEST)
    test_archive_clear_error.c
    test_archive_cmdline.c
    test_archive_digest.c
-    test_archive_getdate.c
    test_archive_match_owner.c
    test_archive_match_path.c
    test_archive_match_time.c
+    test_archive_parse_date.c
    test_archive_pathmatch.c
    test_archive_read.c
    test_archive_read_add_passphrase.c
--- a/libarchive/test/test_archive_match_time.c
+++ b/libarchive/test/test_archive_match_time.c
@@ -25,8 +25,7 @@

 #include "test.h"

-#define __LIBARCHIVE_BUILD 1
-#include "archive_getdate.h"
+#define parse_date archive_parse_date

 static void
 test_newer_time(void)
@@ -102,27 +101,27 @@ test_newer_time_str(void)

 	/* Test1: Allow newer time. */
 	archive_entry_copy_pathname(ae, "file1");
-	t = __archive_get_date(now, "1980/2/1 0:0:0 UTC");
+	t = parse_date(now, "1980/2/1 0:0:0 UTC");
 	archive_entry_set_mtime(ae, t, 0);
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Both Its mtime and ctime should be excluded");
 	assertEqualInt(1, archive_match_time_excluded(m, ae));
 	assertEqualInt(1, archive_match_excluded(m, ae));
-	t = __archive_get_date(now, "1980/1/1 0:0:0 UTC");
+	t = parse_date(now, "1980/1/1 0:0:0 UTC");
 	archive_entry_set_mtime(ae, t, 0);
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Both Its mtime and ctime should be excluded");
 	assertEqualInt(1, archive_match_time_excluded(m, ae));
 	assertEqualInt(1, archive_match_excluded(m, ae));

-	t = __archive_get_date(now, "1980/2/1 0:0:1 UTC");
+	t = parse_date(now, "1980/2/1 0:0:1 UTC");
 	archive_entry_set_mtime(ae, t, 0);
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Both Its mtime and ctime should not be excluded");
 	assertEqualInt(0, archive_match_time_excluded(m, ae));
 	assertEqualInt(0, archive_match_excluded(m, ae));

-	t = __archive_get_date(now, "1980/2/1 0:0:0 UTC");
+	t = parse_date(now, "1980/2/1 0:0:0 UTC");
 	archive_entry_set_mtime(ae, t, 1);
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Its mtime should be excluded");
@@ -143,20 +142,20 @@ test_newer_time_str(void)
 	    "1980/2/1 0:0:0 UTC"));

 	archive_entry_copy_pathname(ae, "file1");
-	t = __archive_get_date(now, "1980/2/1 0:0:0 UTC");
+	t = parse_date(now, "1980/2/1 0:0:0 UTC");
 	archive_entry_set_mtime(ae, t, 0);
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Both Its mtime and ctime should not be excluded");
 	assertEqualInt(0, archive_match_time_excluded(m, ae));
 	assertEqualInt(0, archive_match_excluded(m, ae));
-	t = __archive_get_date(now, "1980/1/1 0:0:0 UTC");
+	t = parse_date(now, "1980/1/1 0:0:0 UTC");
 	archive_entry_set_mtime(ae, t, 0);
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Both Its mtime and ctime should be excluded");
 	assertEqualInt(1, archive_match_time_excluded(m, ae));
 	assertEqualInt(1, archive_match_excluded(m, ae));

-	t = __archive_get_date(now, "1980/2/1 0:0:1 UTC");
+	t = parse_date(now, "1980/2/1 0:0:1 UTC");
 	archive_entry_set_mtime(ae, t, 0);
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Both Its mtime and ctime should not be excluded");
@@ -190,27 +189,27 @@ test_newer_time_str_w(void)

 	/* Test1: Allow newer time. */
 	archive_entry_copy_pathname(ae, "file1");
-	t = __archive_get_date(now, "1980/2/1 0:0:0 UTC");
+	t = parse_date(now, "1980/2/1 0:0:0 UTC");
 	archive_entry_set_mtime(ae, t, 0);
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Both Its mtime and ctime should be excluded");
 	assertEqualInt(1, archive_match_time_excluded(m, ae));
 	assertEqualInt(1, archive_match_excluded(m, ae));
-	t = __archive_get_date(now, "1980/1/1 0:0:0 UTC");
+	t = parse_date(now, "1980/1/1 0:0:0 UTC");
 	archive_entry_set_mtime(ae, t, 0);
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Both Its mtime and ctime should be excluded");
 	assertEqualInt(1, archive_match_time_excluded(m, ae));
 	assertEqualInt(1, archive_match_excluded(m, ae));

-	t = __archive_get_date(now, "1980/2/1 0:0:1 UTC");
+	t = parse_date(now, "1980/2/1 0:0:1 UTC");
 	archive_entry_set_mtime(ae, t, 0);
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Both Its mtime and ctime should not be excluded");
 	assertEqualInt(0, archive_match_time_excluded(m, ae));
 	assertEqualInt(0, archive_match_excluded(m, ae));

-	t = __archive_get_date(now, "1980/2/1 0:0:0 UTC");
+	t = parse_date(now, "1980/2/1 0:0:0 UTC");
 	archive_entry_set_mtime(ae, t, 1);
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Its mtime should be excluded");
@@ -231,20 +230,20 @@ test_newer_time_str_w(void)
 	    L"1980/2/1 0:0:0 UTC"));

 	archive_entry_copy_pathname(ae, "file1");
-	t = __archive_get_date(now, "1980/2/1 0:0:0 UTC");
+	t = parse_date(now, "1980/2/1 0:0:0 UTC");
 	archive_entry_set_mtime(ae, t, 0);
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Both Its mtime and ctime should not be excluded");
 	assertEqualInt(0, archive_match_time_excluded(m, ae));
 	assertEqualInt(0, archive_match_excluded(m, ae));
-	t = __archive_get_date(now, "1980/1/1 0:0:0 UTC");
+	t = parse_date(now, "1980/1/1 0:0:0 UTC");
 	archive_entry_set_mtime(ae, t, 0);
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Both Its mtime and ctime should be excluded");
 	assertEqualInt(1, archive_match_time_excluded(m, ae));
 	assertEqualInt(1, archive_match_excluded(m, ae));

-	t = __archive_get_date(now, "1980/2/1 0:0:1 UTC");
+	t = parse_date(now, "1980/2/1 0:0:1 UTC");
 	archive_entry_set_mtime(ae, t, 0);
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Both Its mtime and ctime should not be excluded");
@@ -569,37 +568,37 @@ test_older_time_str(void)
 	    ARCHIVE_MATCH_OLDER, "1980/2/1 0:0:0 UTC"));

 	archive_entry_copy_pathname(ae, "file1");
-	t = __archive_get_date(now, "1980/2/1 0:0:0 UTC");
+	t = parse_date(now, "1980/2/1 0:0:0 UTC");
 	archive_entry_set_mtime(ae, t, 0);
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Both Its mtime and ctime should be excluded");
 	assertEqualInt(1, archive_match_time_excluded(m, ae));
 	assertEqualInt(1, archive_match_excluded(m, ae));
-	t = __archive_get_date(now, "1980/1/1 0:0:0 UTC");
+	t = parse_date(now, "1980/1/1 0:0:0 UTC");
 	archive_entry_set_mtime(ae, t, 0);
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Both Its mtime and ctime should not be excluded");
 	assertEqualInt(0, archive_match_time_excluded(m, ae));
 	assertEqualInt(0, archive_match_excluded(m, ae));

-	t = __archive_get_date(now, "1980/3/1 0:0:0 UTC");
+	t = parse_date(now, "1980/3/1 0:0:0 UTC");
 	archive_entry_set_mtime(ae, t, 0);
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Both Its mtime and ctime should be excluded");
 	assertEqualInt(1, archive_match_time_excluded(m, ae));
 	assertEqualInt(1, archive_match_excluded(m, ae));

-	t = __archive_get_date(now, "1980/3/1 0:0:0 UTC");
+	t = parse_date(now, "1980/3/1 0:0:0 UTC");
 	archive_entry_set_mtime(ae, t, 0);
-	t = __archive_get_date(now, "1980/1/1 0:0:0 UTC");
+	t = parse_date(now, "1980/1/1 0:0:0 UTC");
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Its mtime should be excluded");
 	assertEqualInt(1, archive_match_time_excluded(m, ae));
 	assertEqualInt(1, archive_match_excluded(m, ae));

-	t = __archive_get_date(now, "1980/1/1 0:0:0 UTC");
+	t = parse_date(now, "1980/1/1 0:0:0 UTC");
 	archive_entry_set_mtime(ae, t, 0);
-	t = __archive_get_date(now, "1980/3/1 0:0:0 UTC");
+	t = parse_date(now, "1980/3/1 0:0:0 UTC");
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Its ctime should be excluded");
 	assertEqualInt(1, archive_match_time_excluded(m, ae));
@@ -612,20 +611,20 @@ test_older_time_str(void)
 	    "1980/2/1 0:0:0 UTC"));

 	archive_entry_copy_pathname(ae, "file1");
-	t = __archive_get_date(now, "1980/2/1 0:0:0 UTC");
+	t = parse_date(now, "1980/2/1 0:0:0 UTC");
 	archive_entry_set_mtime(ae, t, 0);
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Both Its mtime and ctime should not be excluded");
 	assertEqualInt(0, archive_match_time_excluded(m, ae));
 	assertEqualInt(0, archive_match_excluded(m, ae));
-	t = __archive_get_date(now, "1980/1/1 0:0:0 UTC");
+	t = parse_date(now, "1980/1/1 0:0:0 UTC");
 	archive_entry_set_mtime(ae, t, 0);
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Both Its mtime and ctime should not be excluded");
 	assertEqualInt(0, archive_match_time_excluded(m, ae));
 	assertEqualInt(0, archive_match_excluded(m, ae));

-	t = __archive_get_date(now, "1980/3/1 0:0:0 UTC");
+	t = parse_date(now, "1980/3/1 0:0:0 UTC");
 	archive_entry_set_mtime(ae, t, 0);
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Both Its mtime and ctime should be excluded");
@@ -659,37 +658,37 @@ test_older_time_str_w(void)
 	    ARCHIVE_MATCH_OLDER, L"1980/2/1 0:0:0 UTC"));

 	archive_entry_copy_pathname(ae, "file1");
-	t = __archive_get_date(now, "1980/2/1 0:0:0 UTC");
+	t = parse_date(now, "1980/2/1 0:0:0 UTC");
 	archive_entry_set_mtime(ae, t, 0);
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Both Its mtime and ctime should be excluded");
 	assertEqualInt(1, archive_match_time_excluded(m, ae));
 	assertEqualInt(1, archive_match_excluded(m, ae));
-	t = __archive_get_date(now, "1980/1/1 0:0:0 UTC");
+	t = parse_date(now, "1980/1/1 0:0:0 UTC");
 	archive_entry_set_mtime(ae, t, 0);
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Both Its mtime and ctime should not be excluded");
 	assertEqualInt(0, archive_match_time_excluded(m, ae));
 	assertEqualInt(0, archive_match_excluded(m, ae));

-	t = __archive_get_date(now, "1980/3/1 0:0:0 UTC");
+	t = parse_date(now, "1980/3/1 0:0:0 UTC");
 	archive_entry_set_mtime(ae, t, 0);
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Both Its mtime and ctime should be excluded");
 	assertEqualInt(1, archive_match_time_excluded(m, ae));
 	assertEqualInt(1, archive_match_excluded(m, ae));

-	t = __archive_get_date(now, "1980/3/1 0:0:0 UTC");
+	t = parse_date(now, "1980/3/1 0:0:0 UTC");
 	archive_entry_set_mtime(ae, t, 0);
-	t = __archive_get_date(now, "1980/1/1 0:0:0 UTC");
+	t = parse_date(now, "1980/1/1 0:0:0 UTC");
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Its mtime should be excluded");
 	assertEqualInt(1, archive_match_time_excluded(m, ae));
 	assertEqualInt(1, archive_match_excluded(m, ae));

-	t = __archive_get_date(now, "1980/1/1 0:0:0 UTC");
+	t = parse_date(now, "1980/1/1 0:0:0 UTC");
 	archive_entry_set_mtime(ae, t, 0);
-	t = __archive_get_date(now, "1980/3/1 0:0:0 UTC");
+	t = parse_date(now, "1980/3/1 0:0:0 UTC");
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Its ctime should be excluded");
 	assertEqualInt(1, archive_match_time_excluded(m, ae));
@@ -702,20 +701,20 @@ test_older_time_str_w(void)
 	    L"1980/2/1 0:0:0 UTC"));

 	archive_entry_copy_pathname(ae, "file1");
-	t = __archive_get_date(now, "1980/2/1 0:0:0 UTC");
+	t = parse_date(now, "1980/2/1 0:0:0 UTC");
 	archive_entry_set_mtime(ae, t, 0);
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Both Its mtime and ctime should not be excluded");
 	assertEqualInt(0, archive_match_time_excluded(m, ae));
 	assertEqualInt(0, archive_match_excluded(m, ae));
-	t = __archive_get_date(now, "1980/1/1 0:0:0 UTC");
+	t = parse_date(now, "1980/1/1 0:0:0 UTC");
 	archive_entry_set_mtime(ae, t, 0);
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Both Its mtime and ctime should not be excluded");
 	assertEqualInt(0, archive_match_time_excluded(m, ae));
 	assertEqualInt(0, archive_match_excluded(m, ae));

-	t = __archive_get_date(now, "1980/3/1 0:0:0 UTC");
+	t = parse_date(now, "1980/3/1 0:0:0 UTC");
 	archive_entry_set_mtime(ae, t, 0);
 	archive_entry_set_ctime(ae, t, 0);
 	failure("Both Its mtime and ctime should be excluded");
--- a/libarchive/test/test_archive_parse_date.c
+++ b/libarchive/test/test_archive_parse_date.c
@@ -26,16 +26,13 @@

 #include <time.h>

-#define __LIBARCHIVE_BUILD 1
-#include "archive_getdate.h"
-
 /*
- * Verify that the getdate() function works.
+ * Verify that the archive_parse_date() function works.
 */

-#define get_date __archive_get_date
+#define get_date archive_parse_date

-DEFINE_TEST(test_archive_getdate)
+DEFINE_TEST(test_archive_parse_date)
 {
 	time_t now = time(NULL);

--- a/tar/bsdtar.1
+++ b/tar/bsdtar.1
@@ -196,6 +196,11 @@ 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 clamp-mtime
+(use with
+.Fl Fl mtime )
+Only set the modification time if the file is newer than the date specified in
+.Fl Fl mtime .
 .It Fl Fl clear-nochange-fflags
 (x mode only)
 Before removing file system objects to replace them, clear platform-specific
@@ -416,6 +421,9 @@ is run in x mode as root.
 Currently supported only for pax formats
 .Po including "pax restricted", the default tar format for
 .Nm bsdtar Pc
+.It Fl Fl mtime Ar date
+(c, r, u modes only)
+Set the modification times of added files to the specified date.
 .It Fl n , Fl Fl norecurse , Fl Fl no-recursion
 Do not operate recursively on the content of directories.
 .It Fl Fl newer Ar date
--- a/tar/bsdtar.c
+++ b/tar/bsdtar.c
@@ -146,6 +146,7 @@ main(int argc, char **argv)
 	char			 possible_help_request;
 	char			 buff[16];
 	long			 l;
+	time_t			now;

 	/*
 	 * Use a pointer for consistency, but stack-allocated storage
@@ -160,6 +161,7 @@ main(int argc, char **argv)
 	compression = compression2 = '\0';
 	compression_name = compression2_name = NULL;
 	compress_program = NULL;
+	time(&now);

 #if defined(HAVE_SIGACTION)
 	{ /* Set up signal handling. */
@@ -676,6 +678,16 @@ main(int argc, char **argv)
 				}
 			}
 			break;
+		case OPTION_MTIME: /* GNU tar */
+			bsdtar->has_mtime = 1;
+			bsdtar->mtime = archive_parse_date(now, bsdtar->argument);
+			if (bsdtar->mtime == (time_t)-1) {
+				lafe_errc(1, 0, "Invalid argument to --mtime (bad date string)");
+			}
+			break;
+		case OPTION_CLAMP_MTIME: /* GNU tar */
+			bsdtar->clamp_mtime = 1;
+			break;
 #if 0
 		/*
 		 * The common BSD -P option is not necessary, since
@@ -962,6 +974,10 @@ main(int argc, char **argv)
 		only_mode(bsdtar, buff, "cru");
 	}

+	if (!bsdtar->has_mtime && bsdtar->clamp_mtime)
+		lafe_errc(1, 0,
+		    "--clamp-mtime is not valid without --mtime <date>");
+
 	/*
 	 * When creating an archive from a directory tree, the directory
 	 * walking code will already avoid entering directories when
@@ -1066,6 +1082,8 @@ static const char *long_help_msg =
 	"  -z, -j, -J, --lzma  Compress archive with gzip/bzip2/xz/lzma\n"
 	"  --format {ustar|pax|cpio|shar}  Select archive format\n"
 	"  --exclude <pattern>  Skip files that match pattern\n"
+	"  --mtime <date>  Set modification times for added files\n"
+	"  --clamp-mtime   Only set modification times for files newer than --mtime\n"
 	"  -C <dir>  Change to <dir> before processing remaining files\n"
 	"  @<archive>  Add entries from <archive> to output\n"
 	"List: %p -t [options] [<patterns>]\n"
--- a/tar/bsdtar.h
+++ b/tar/bsdtar.h
@@ -46,6 +46,9 @@ struct bsdtar {
 	char		  symlink_mode; /* H or L, per BSD conventions */
 	const char	 *option_options; /* --options */
 	char		  day_first; /* show day before month in -tv output */
+	char		has_mtime; /* --mtime exists (0 or 1) */
+	char		clamp_mtime; /* --clamp-mtime (0 or 1)*/
+	time_t		mtime; /* --mtime */
 	struct creation_set *cset;

 	/* Option parser state */
@@ -175,11 +178,14 @@ enum {
 	OPTION_VERSION,
 	OPTION_XATTRS,
 	OPTION_ZSTD,
+	OPTION_MTIME,
+	OPTION_CLAMP_MTIME,
 };

 int	bsdtar_getopt(struct bsdtar *);
 void	do_chdir(struct bsdtar *);
 int	edit_pathname(struct bsdtar *, struct archive_entry *);
+void	edit_mtime(struct bsdtar *, struct archive_entry *);
 int	need_report(void);
 int	pathcmp(const char *a, const char *b);
 void	safe_fprintf(FILE * restrict, const char * restrict fmt, ...) __LA_PRINTF(2, 3);
--- a/tar/cmdline.c
+++ b/tar/cmdline.c
@@ -57,6 +57,7 @@ static const struct bsdtar_option {
 	{ "cd",                   1, 'C' },
 	{ "check-links",          0, OPTION_CHECK_LINKS },
 	{ "chroot",               0, OPTION_CHROOT },
+	{ "clamp-mtime",          0, OPTION_CLAMP_MTIME },
 	{ "clear-nochange-fflags", 0, OPTION_CLEAR_NOCHANGE_FFLAGS },
 	{ "compress",             0, 'Z' },
 	{ "confirmation",         0, 'w' },
@@ -95,6 +96,7 @@ static const struct bsdtar_option {
 	{ "lzop",                 0, OPTION_LZOP },
 	{ "mac-metadata",         0, OPTION_MAC_METADATA },
 	{ "modification-time",    0, 'm' },
+	{ "mtime",                1, OPTION_MTIME },
 	{ "newer",		  1, OPTION_NEWER_CTIME },
 	{ "newer-ctime",	  1, OPTION_NEWER_CTIME },
 	{ "newer-ctime-than",	  1, OPTION_NEWER_CTIME_THAN },
--- a/tar/test/CMakeLists.txt
+++ b/tar/test/CMakeLists.txt
@@ -58,6 +58,7 @@ IF(ENABLE_TAR AND ENABLE_TEST)
    test_option_lz4.c
    test_option_lzma.c
    test_option_lzop.c
+    test_option_mtime.c
    test_option_n.c
    test_option_newer_than.c
    test_option_nodump.c
--- a/tar/test/test_option_mtime.c
+++ b/tar/test/test_option_mtime.c
@@ -0,0 +1,82 @@
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ *
+ * Copyright (c) 2025 Zhaofeng Li
+ * All rights reserved.
+ */
+#include "test.h"
+
+#if defined(_WIN32) && !defined(__CYGWIN__)
+/* system() on Windows runs its arguments through CMD.EXE, which has
+ * notoriously unfriendly quoting rules. The current best documented way around
+ * them is to wrap your *entire commandline* in sacrificial quotes.
+ *
+ * See CMD.EXE /? for more information. Excerpted here:
+ * | Otherwise, old behavior is to see if the first character is
+ * | a quote character and if so, strip the leading character and
+ * | remove the last quote character on the command line, preserving
+ * | any text after the last quote character.
+ *
+ * Since this test makes heavy use of systemf() with quoted arguments inside
+ * the commandline, this macro is unfortunately an easier workaround.
+ */
+#define systemf(command, ...) systemf("\"" command "\"", __VA_ARGS__)
+#endif
+
+DEFINE_TEST(test_option_mtime)
+{
+	/* Create three files with different mtimes. */
+	assertMakeDir("in", 0755);
+	assertChdir("in");
+	assertMakeFile("new_mtime", 0666, "new");
+	assertUtimes("new_mtime", 100000, 0, 100000, 0);
+	assertMakeFile("mid_mtime", 0666, "mid");
+	assertUtimes("mid_mtime", 10000, 0, 10000, 0);
+	assertMakeFile("old_mtime", 0666, "old");
+	// assertion_utimes silently discards 0 :(
+	assertUtimes("old_mtime", 1, 0, 1, 0);
+
+	/* Archive with --mtime 86400 */
+	assertEqualInt(0,
+		systemf("%s --format pax -cf ../noclamp.tar "
+			"--mtime \"1970/1/2 0:0:0 UTC\" .",
+			testprog));
+	assertChdir("..");
+
+	assertMakeDir("out.noclamp", 0755);
+	assertChdir("out.noclamp");
+	assertEqualInt(0, systemf("%s xf ../noclamp.tar", testprog));
+	assertFileMtime("new_mtime", 86400, 0);
+	assertFileMtime("mid_mtime", 86400, 0);
+	assertFileMtime("old_mtime", 86400, 0);
+	assertChdir("..");
+
+	/* Archive with --mtime 86400 --clamp-mtime */
+	assertChdir("in");
+	assertEqualInt(0,
+		systemf("%s --format pax -cf ../clamp.tar "
+			"--mtime \"1970/1/2 0:0:0 UTC\" --clamp-mtime .",
+			testprog));
+	assertChdir("..");
+
+	assertMakeDir("out.clamp", 0755);
+	assertChdir("out.clamp");
+	assertEqualInt(0, systemf("%s xf ../clamp.tar", testprog));
+	assertFileMtime("new_mtime", 86400, 0);
+	assertFileMtime("mid_mtime", 10000, 0);
+	assertFileMtime("old_mtime", 1, 0);
+	assertChdir("..");
+
+	/* Archive-to-archive copy with --mtime 0 */
+	assertEqualInt(0,
+		systemf("%s --format pax -cf ./archive2archive.tar "
+			"--mtime \"1970/1/1 0:0:0 UTC\" @noclamp.tar",
+			testprog));
+	assertMakeDir("out.archive2archive", 0755);
+	assertChdir("out.archive2archive");
+	assertEqualInt(0, systemf("%s xf ../archive2archive.tar", testprog));
+	assertFileMtime("new_mtime", 0, 0);
+	assertFileMtime("mid_mtime", 0, 0);
+	assertFileMtime("old_mtime", 0, 0);
+	assertChdir("..");
+}
--- a/tar/util.c
+++ b/tar/util.c
@@ -562,6 +562,20 @@ edit_pathname(struct bsdtar *bsdtar, struct archive_entry *entry)
 	return (0);
 }

+/*
+ * Apply --mtime and --clamp-mtime options.
+ */
+void
+edit_mtime(struct bsdtar *bsdtar, struct archive_entry *entry)
+{
+	if (!bsdtar->has_mtime)
+		return;
+
+	__LA_TIME_T entry_mtime = archive_entry_mtime(entry);
+	if (!bsdtar->clamp_mtime || entry_mtime > bsdtar->mtime)
+		archive_entry_set_mtime(entry, bsdtar->mtime, 0);
+}
+
 /*
 * It would be nice to just use printf() for formatting large numbers,
 * but the compatibility problems are quite a headache.  Hence the
--- a/tar/write.c
+++ b/tar/write.c
@@ -682,6 +682,7 @@ append_archive(struct bsdtar *bsdtar, struct archive *a, struct archive *ina)
 		if ((bsdtar->flags & OPTFLAG_INTERACTIVE) &&
 		    !yes("copy '%s'", archive_entry_pathname(in_entry)))
 			continue;
+		edit_mtime(bsdtar, in_entry);
 		if (bsdtar->verbose > 1) {
 			safe_fprintf(stderr, "a ");
 			list_item_verbose(bsdtar, stderr, in_entry);
@@ -908,6 +909,9 @@ write_hierarchy(struct bsdtar *bsdtar, struct archive *a, const char *path)
 		if (edit_pathname(bsdtar, entry))
 			continue;

+		/* Rewrite the mtime. */
+		edit_mtime(bsdtar, entry);
+
 		/* Display entry as we process it. */
 		if (bsdtar->verbose > 1) {
 			safe_fprintf(stderr, "a ");