Update libarchive to v2.5.5

1 files changed, 1438 insertions, 0 deletions

diff --git a/libarchive/libarchive-2.5.5/tar/write.c b/libarchive/libarchive-2.5.5/tar/write.c
new file mode 100644
index 0000000..1a6e928
--- /dev/null
+++ b/libarchive/libarchive-2.5.5/tar/write.c
@@ -0,0 +1,1438 @@
+/*-
+ * Copyright (c) 2003-2007 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.
+ */
+
+#include "bsdtar_platform.h"
+__FBSDID("$FreeBSD: src/usr.bin/tar/write.c,v 1.70 2008/05/26 17:10:10 kientzle Exp $");
+
+#ifdef HAVE_SYS_TYPES_H
+#include <sys/types.h>
+#endif
+#ifdef HAVE_SYS_ACL_H
+#include <sys/acl.h>
+#endif
+#ifdef HAVE_SYS_IOCTL_H
+#include <sys/ioctl.h>
+#endif
+#ifdef HAVE_SYS_STAT_H
+#include <sys/stat.h>
+#endif
+#ifdef HAVE_ATTR_XATTR_H
+#include <attr/xattr.h>
+#endif
+#ifdef HAVE_ERRNO_H
+#include <errno.h>
+#endif
+#ifdef HAVE_EXT2FS_EXT2_FS_H
+#include <ext2fs/ext2_fs.h>
+#endif
+#ifdef HAVE_FCNTL_H
+#include <fcntl.h>
+#endif
+#ifdef HAVE_FNMATCH_H
+#include <fnmatch.h>
+#endif
+#ifdef HAVE_GRP_H
+#include <grp.h>
+#endif
+#ifdef HAVE_LIMITS_H
+#include <limits.h>
+#endif
+#ifdef HAVE_LINUX_FS_H
+#include <linux/fs.h>	/* for Linux file flags */
+#endif
+#ifdef HAVE_PWD_H
+#include <pwd.h>
+#endif
+#include <stdio.h>
+#ifdef HAVE_STDLIB_H
+#include <stdlib.h>
+#endif
+#ifdef HAVE_STRING_H
+#include <string.h>
+#endif
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
+#include "bsdtar.h"
+#include "tree.h"
+
+/* Fixed size of uname/gname caches. */
+#define	name_cache_size 101
+
+static const char * const NO_NAME = "(noname)";
+
+struct archive_dir_entry {
+	struct archive_dir_entry	*next;
+	time_t			 mtime_sec;
+	int			 mtime_nsec;
+	char			*name;
+};
+
+struct archive_dir {
+	struct archive_dir_entry *head, *tail;
+};
+
+struct name_cache {
+	int	probes;
+	int	hits;
+	size_t	size;
+	struct {
+		id_t id;
+		const char *name;
+	} cache[name_cache_size];
+};
+
+static void		 add_dir_list(struct bsdtar *bsdtar, const char *path,
+			     time_t mtime_sec, int mtime_nsec);
+static int		 append_archive(struct bsdtar *, struct archive *,
+			     struct archive *ina);
+static int		 append_archive_filename(struct bsdtar *,
+			     struct archive *, const char *fname);
+static void		 archive_names_from_file(struct bsdtar *bsdtar,
+			     struct archive *a);
+static int		 archive_names_from_file_helper(struct bsdtar *bsdtar,
+			     const char *line);
+static int		 copy_file_data(struct bsdtar *bsdtar,
+			     struct archive *a, struct archive *ina);
+static void		 create_cleanup(struct bsdtar *);
+static void		 free_cache(struct name_cache *cache);
+static const char *	 lookup_gname(struct bsdtar *bsdtar, gid_t gid);
+static int		 lookup_gname_helper(struct bsdtar *bsdtar,
+			     const char **name, id_t gid);
+static const char *	 lookup_uname(struct bsdtar *bsdtar, uid_t uid);
+static int		 lookup_uname_helper(struct bsdtar *bsdtar,
+			     const char **name, id_t uid);
+static int		 new_enough(struct bsdtar *, const char *path,
+			     const struct stat *);
+static void		 setup_acls(struct bsdtar *, struct archive_entry *,
+			     const char *path);
+static void		 setup_xattrs(struct bsdtar *, struct archive_entry *,
+			     const char *path);
+static void		 test_for_append(struct bsdtar *);
+static void		 write_archive(struct archive *, struct bsdtar *);
+static void		 write_entry(struct bsdtar *, struct archive *,
+			     const struct stat *, const char *pathname,
+			     const char *accpath);
+static void		 write_entry_backend(struct bsdtar *, struct archive *,
+			     struct archive_entry *, int);
+static int		 write_file_data(struct bsdtar *, struct archive *,
+			     int fd);
+static void		 write_hierarchy(struct bsdtar *, struct archive *,
+			     const char *);
+
+void
+tar_mode_c(struct bsdtar *bsdtar)
+{
+	struct archive *a;
+	int r;
+
+	if (*bsdtar->argv == NULL && bsdtar->names_from_file == NULL)
+		bsdtar_errc(bsdtar, 1, 0, "no files or directories specified");
+
+	/* We want to catch SIGINFO and SIGUSR1. */
+	siginfo_init(bsdtar);
+
+	a = archive_write_new();
+
+	/* Support any format that the library supports. */
+	if (bsdtar->create_format == NULL) {
+		r = archive_write_set_format_pax_restricted(a);
+		bsdtar->create_format = "pax restricted";
+	} else {
+		r = archive_write_set_format_by_name(a, bsdtar->create_format);
+	}
+	if (r != ARCHIVE_OK) {
+		fprintf(stderr, "Can't use format %s: %s\n",
+		    bsdtar->create_format,
+		    archive_error_string(a));
+		usage(bsdtar);
+	}
+
+	/*
+	 * If user explicitly set the block size, then assume they
+	 * want the last block padded as well.  Otherwise, use the
+	 * default block size and accept archive_write_open_file()'s
+	 * default padding decisions.
+	 */
+	if (bsdtar->bytes_per_block != 0) {
+		archive_write_set_bytes_per_block(a, bsdtar->bytes_per_block);
+		archive_write_set_bytes_in_last_block(a,
+		    bsdtar->bytes_per_block);
+	} else
+		archive_write_set_bytes_per_block(a, DEFAULT_BYTES_PER_BLOCK);
+
+	if (bsdtar->compress_program) {
+		archive_write_set_compression_program(a, bsdtar->compress_program);
+	} else {
+		switch (bsdtar->create_compression) {
+		case 0:
+			archive_write_set_compression_none(a);
+			break;
+#ifdef HAVE_LIBBZ2
+		case 'j': case 'y':
+			archive_write_set_compression_bzip2(a);
+			break;
+#endif
+#ifdef HAVE_LIBZ
+		case 'z':
+			archive_write_set_compression_gzip(a);
+			break;
+#endif
+		case 'Z':
+			archive_write_set_compression_compress(a);
+			break;
+		default:
+			bsdtar_errc(bsdtar, 1, 0,
+			    "Unrecognized compression option -%c",
+			    bsdtar->create_compression);
+		}
+	}
+
+	r = archive_write_open_file(a, bsdtar->filename);
+	if (r != ARCHIVE_OK)
+		bsdtar_errc(bsdtar, 1, 0, archive_error_string(a));
+
+	write_archive(a, bsdtar);
+
+	if (bsdtar->option_totals) {
+		fprintf(stderr, "Total bytes written: " BSDTAR_FILESIZE_PRINTF "\n",
+		    (BSDTAR_FILESIZE_TYPE)archive_position_compressed(a));
+	}
+
+	archive_write_finish(a);
+
+	/* Restore old SIGINFO + SIGUSR1 handlers. */
+	siginfo_done(bsdtar);
+}
+
+/*
+ * Same as 'c', except we only support tar or empty formats in
+ * uncompressed files on disk.
+ */
+void
+tar_mode_r(struct bsdtar *bsdtar)
+{
+	off_t	end_offset;
+	int	format;
+	struct archive *a;
+	struct archive_entry *entry;
+	int	r;
+
+	/* Sanity-test some arguments and the file. */
+	test_for_append(bsdtar);
+
+	/* We want to catch SIGINFO and SIGUSR1. */
+	siginfo_init(bsdtar);
+
+	format = ARCHIVE_FORMAT_TAR_PAX_RESTRICTED;
+
+	bsdtar->fd = open(bsdtar->filename, O_RDWR | O_CREAT, 0666);
+	if (bsdtar->fd < 0)
+		bsdtar_errc(bsdtar, 1, errno,
+		    "Cannot open %s", bsdtar->filename);
+
+	a = archive_read_new();
+	archive_read_support_compression_all(a);
+	archive_read_support_format_tar(a);
+	archive_read_support_format_gnutar(a);
+	r = archive_read_open_fd(a, bsdtar->fd, 10240);
+	if (r != ARCHIVE_OK)
+		bsdtar_errc(bsdtar, 1, archive_errno(a),
+		    "Can't read archive %s: %s", bsdtar->filename,
+		    archive_error_string(a));
+	while (0 == archive_read_next_header(a, &entry)) {
+		if (archive_compression(a) != ARCHIVE_COMPRESSION_NONE) {
+			archive_read_finish(a);
+			close(bsdtar->fd);
+			bsdtar_errc(bsdtar, 1, 0,
+			    "Cannot append to compressed archive.");
+		}
+		/* Keep going until we hit end-of-archive */
+		format = archive_format(a);
+	}
+
+	end_offset = archive_read_header_position(a);
+	archive_read_finish(a);
+
+	/* Re-open archive for writing */
+	a = archive_write_new();
+	archive_write_set_compression_none(a);
+	/*
+	 * Set the format to be used for writing.  To allow people to
+	 * extend empty files, we need to allow them to specify the format,
+	 * which opens the possibility that they will specify a format that
+	 * doesn't match the existing format.  Hence, the following bit
+	 * of arcane ugliness.
+	 */
+
+	if (bsdtar->create_format != NULL) {
+		/* If the user requested a format, use that, but ... */
+		archive_write_set_format_by_name(a,
+		    bsdtar->create_format);
+		/* ... complain if it's not compatible. */
+		format &= ARCHIVE_FORMAT_BASE_MASK;
+		if (format != (int)(archive_format(a) & ARCHIVE_FORMAT_BASE_MASK)
+		    && format != ARCHIVE_FORMAT_EMPTY) {
+			bsdtar_errc(bsdtar, 1, 0,
+			    "Format %s is incompatible with the archive %s.",
+			    bsdtar->create_format, bsdtar->filename);
+		}
+	} else {
+		/*
+		 * Just preserve the current format, with a little care
+		 * for formats that libarchive can't write.
+		 */
+		if (format == ARCHIVE_FORMAT_TAR_GNUTAR)
+			/* TODO: When gtar supports pax, use pax restricted. */
+			format = ARCHIVE_FORMAT_TAR_USTAR;
+		if (format == ARCHIVE_FORMAT_EMPTY)
+			format = ARCHIVE_FORMAT_TAR_PAX_RESTRICTED;
+		archive_write_set_format(a, format);
+	}
+	lseek(bsdtar->fd, end_offset, SEEK_SET); /* XXX check return val XXX */
+	archive_write_open_fd(a, bsdtar->fd); /* XXX check return val XXX */
+
+	write_archive(a, bsdtar); /* XXX check return val XXX */
+
+	if (bsdtar->option_totals) {
+		fprintf(stderr, "Total bytes written: " BSDTAR_FILESIZE_PRINTF "\n",
+		    (BSDTAR_FILESIZE_TYPE)archive_position_compressed(a));
+	}
+
+	archive_write_finish(a);
+	close(bsdtar->fd);
+	bsdtar->fd = -1;
+}
+
+void
+tar_mode_u(struct bsdtar *bsdtar)
+{
+	off_t			 end_offset;
+	struct archive		*a;
+	struct archive_entry	*entry;
+	int			 format;
+	struct archive_dir_entry	*p;
+	struct archive_dir	 archive_dir;
+
+	bsdtar->archive_dir = &archive_dir;
+	memset(&archive_dir, 0, sizeof(archive_dir));
+
+	format = ARCHIVE_FORMAT_TAR_PAX_RESTRICTED;
+
+	/* Sanity-test some arguments and the file. */
+	test_for_append(bsdtar);
+
+	/* We want to catch SIGINFO and SIGUSR1. */
+	siginfo_init(bsdtar);
+
+	bsdtar->fd = open(bsdtar->filename, O_RDWR);
+	if (bsdtar->fd < 0)
+		bsdtar_errc(bsdtar, 1, errno,
+		    "Cannot open %s", bsdtar->filename);
+
+	a = archive_read_new();
+	archive_read_support_compression_all(a);
+	archive_read_support_format_tar(a);
+	archive_read_support_format_gnutar(a);
+	if (archive_read_open_fd(a, bsdtar->fd,
+	    bsdtar->bytes_per_block != 0 ? bsdtar->bytes_per_block :
+		DEFAULT_BYTES_PER_BLOCK) != ARCHIVE_OK) {
+		bsdtar_errc(bsdtar, 1, 0,
+		    "Can't open %s: %s", bsdtar->filename,
+		    archive_error_string(a));
+	}
+
+	/* Build a list of all entries and their recorded mod times. */
+	while (0 == archive_read_next_header(a, &entry)) {
+		if (archive_compression(a) != ARCHIVE_COMPRESSION_NONE) {
+			archive_read_finish(a);
+			close(bsdtar->fd);
+			bsdtar_errc(bsdtar, 1, 0,
+			    "Cannot append to compressed archive.");
+		}
+		add_dir_list(bsdtar, archive_entry_pathname(entry),
+		    archive_entry_mtime(entry),
+		    archive_entry_mtime_nsec(entry));
+		/* Record the last format determination we see */
+		format = archive_format(a);
+		/* Keep going until we hit end-of-archive */
+	}
+
+	end_offset = archive_read_header_position(a);
+	archive_read_finish(a);
+
+	/* Re-open archive for writing. */
+	a = archive_write_new();
+	archive_write_set_compression_none(a);
+	/*
+	 * Set format to same one auto-detected above, except that
+	 * we don't write GNU tar format, so use ustar instead.
+	 */
+	if (format == ARCHIVE_FORMAT_TAR_GNUTAR)
+		format = ARCHIVE_FORMAT_TAR_USTAR;
+	archive_write_set_format(a, format);
+	if (bsdtar->bytes_per_block != 0) {
+		archive_write_set_bytes_per_block(a, bsdtar->bytes_per_block);
+		archive_write_set_bytes_in_last_block(a,
+		    bsdtar->bytes_per_block);
+	} else
+		archive_write_set_bytes_per_block(a, DEFAULT_BYTES_PER_BLOCK);
+	lseek(bsdtar->fd, end_offset, SEEK_SET);
+	ftruncate(bsdtar->fd, end_offset);
+	archive_write_open_fd(a, bsdtar->fd);
+
+	write_archive(a, bsdtar);
+
+	if (bsdtar->option_totals) {
+		fprintf(stderr, "Total bytes written: " BSDTAR_FILESIZE_PRINTF "\n",
+		    (BSDTAR_FILESIZE_TYPE)archive_position_compressed(a));
+	}
+
+	archive_write_finish(a);
+	close(bsdtar->fd);
+	bsdtar->fd = -1;
+
+	while (bsdtar->archive_dir->head != NULL) {
+		p = bsdtar->archive_dir->head->next;
+		free(bsdtar->archive_dir->head->name);
+		free(bsdtar->archive_dir->head);
+		bsdtar->archive_dir->head = p;
+	}
+	bsdtar->archive_dir->tail = NULL;
+}
+
+
+/*
+ * Write user-specified files/dirs to opened archive.
+ */
+static void
+write_archive(struct archive *a, struct bsdtar *bsdtar)
+{
+	const char *arg;
+	struct archive_entry *entry, *sparse_entry;
+
+	if ((bsdtar->resolver = archive_entry_linkresolver_new()) == NULL)
+		bsdtar_errc(bsdtar, 1, 0, "cannot create link resolver");
+	archive_entry_linkresolver_set_strategy(bsdtar->resolver,
+	    archive_format(a));
+
+	if (bsdtar->names_from_file != NULL)
+		archive_names_from_file(bsdtar, a);
+
+	while (*bsdtar->argv) {
+		arg = *bsdtar->argv;
+		if (arg[0] == '-' && arg[1] == 'C') {
+			arg += 2;
+			if (*arg == '\0') {
+				bsdtar->argv++;
+				arg = *bsdtar->argv;
+				if (arg == NULL) {
+					bsdtar_warnc(bsdtar, 1, 0,
+					    "Missing argument for -C");
+					bsdtar->return_value = 1;
+					return;
+				}
+			}
+			set_chdir(bsdtar, arg);
+		} else {
+			if (*arg != '/' && (arg[0] != '@' || arg[1] != '/'))
+				do_chdir(bsdtar); /* Handle a deferred -C */
+			if (*arg == '@') {
+				if (append_archive_filename(bsdtar, a,
+				    arg + 1) != 0)
+					break;
+			} else
+				write_hierarchy(bsdtar, a, arg);
+		}
+		bsdtar->argv++;
+	}
+
+	entry = NULL;
+	archive_entry_linkify(bsdtar->resolver, &entry, &sparse_entry);
+	while (entry != NULL) {
+		int fd = -1;
+		write_entry_backend(bsdtar, a, entry, fd);
+		archive_entry_free(entry);
+		entry = NULL;
+		archive_entry_linkify(bsdtar->resolver, &entry, &sparse_entry);
+	}
+
+	create_cleanup(bsdtar);
+	if (archive_write_close(a)) {
+		bsdtar_warnc(bsdtar, 0, "%s", archive_error_string(a));
+		bsdtar->return_value = 1;
+	}
+}
+
+/*
+ * Archive names specified in file.
+ *
+ * Unless --null was specified, a line containing exactly "-C" will
+ * cause the next line to be a directory to pass to chdir().  If
+ * --null is specified, then a line "-C" is just another filename.
+ */
+void
+archive_names_from_file(struct bsdtar *bsdtar, struct archive *a)
+{
+	bsdtar->archive = a;
+
+	bsdtar->next_line_is_dir = 0;
+	process_lines(bsdtar, bsdtar->names_from_file,
+	    archive_names_from_file_helper);
+	if (bsdtar->next_line_is_dir)
+		bsdtar_errc(bsdtar, 1, errno,
+		    "Unexpected end of filename list; "
+		    "directory expected after -C");
+}
+
+static int
+archive_names_from_file_helper(struct bsdtar *bsdtar, const char *line)
+{
+	if (bsdtar->next_line_is_dir) {
+		set_chdir(bsdtar, line);
+		bsdtar->next_line_is_dir = 0;
+	} else if (!bsdtar->option_null && strcmp(line, "-C") == 0)
+		bsdtar->next_line_is_dir = 1;
+	else {
+		if (*line != '/')
+			do_chdir(bsdtar); /* Handle a deferred -C */
+		write_hierarchy(bsdtar, bsdtar->archive, line);
+	}
+	return (0);
+}
+
+/*
+ * Copy from specified archive to current archive.  Returns non-zero
+ * for write errors (which force us to terminate the entire archiving
+ * operation).  If there are errors reading the input archive, we set
+ * bsdtar->return_value but return zero, so the overall archiving
+ * operation will complete and return non-zero.
+ */
+static int
+append_archive_filename(struct bsdtar *bsdtar, struct archive *a,
+    const char *filename)
+{
+	struct archive *ina;
+	int rc;
+
+	if (strcmp(filename, "-") == 0)
+		filename = NULL; /* Library uses NULL for stdio. */
+
+	ina = archive_read_new();
+	archive_read_support_format_all(ina);
+	archive_read_support_compression_all(ina);
+	if (archive_read_open_file(ina, filename, 10240)) {
+		bsdtar_warnc(bsdtar, 0, "%s", archive_error_string(ina));
+		bsdtar->return_value = 1;
+		return (0);
+	}
+
+	rc = append_archive(bsdtar, a, ina);
+
+	if (archive_errno(ina)) {
+		bsdtar_warnc(bsdtar, 0, "Error reading archive %s: %s",
+		    filename, archive_error_string(ina));
+		bsdtar->return_value = 1;
+	}
+	archive_read_finish(ina);
+
+	return (rc);
+}
+
+static int
+append_archive(struct bsdtar *bsdtar, struct archive *a, struct archive *ina)
+{
+	struct archive_entry *in_entry;
+	int e;
+
+	while (0 == archive_read_next_header(ina, &in_entry)) {
+		if (!new_enough(bsdtar, archive_entry_pathname(in_entry),
+			archive_entry_stat(in_entry)))
+			continue;
+		if (excluded(bsdtar, archive_entry_pathname(in_entry)))
+			continue;
+		if (bsdtar->option_interactive &&
+		    !yes("copy '%s'", archive_entry_pathname(in_entry)))
+			continue;
+		if (bsdtar->verbose)
+			safe_fprintf(stderr, "a %s",
+			    archive_entry_pathname(in_entry));
+		siginfo_setinfo(bsdtar, "copying",
+		    archive_entry_pathname(in_entry),
+		    archive_entry_size(in_entry));
+		siginfo_printinfo(bsdtar, 0);
+
+		e = archive_write_header(a, in_entry);
+		if (e != ARCHIVE_OK) {
+			if (!bsdtar->verbose)
+				bsdtar_warnc(bsdtar, 0, "%s: %s",
+				    archive_entry_pathname(in_entry),
+				    archive_error_string(a));
+			else
+				fprintf(stderr, ": %s", archive_error_string(a));
+		}
+		if (e == ARCHIVE_FATAL)
+			exit(1);
+
+		if (e >= ARCHIVE_WARN) {
+			if (archive_entry_size(in_entry) == 0)
+				archive_read_data_skip(ina);
+			else if (copy_file_data(bsdtar, a, ina))
+				exit(1);
+		}
+
+		if (bsdtar->verbose)
+			fprintf(stderr, "\n");
+	}
+
+	/* Note: If we got here, we saw no write errors, so return success. */
+	return (0);
+}
+
+/* Helper function to copy data between archives. */
+static int
+copy_file_data(struct bsdtar *bsdtar, struct archive *a, struct archive *ina)
+{
+	char	buff[64*1024];
+	ssize_t	bytes_read;
+	ssize_t	bytes_written;
+	off_t	progress = 0;
+
+	bytes_read = archive_read_data(ina, buff, sizeof(buff));
+	while (bytes_read > 0) {
+		siginfo_printinfo(bsdtar, progress);
+
+		bytes_written = archive_write_data(a, buff, bytes_read);
+		if (bytes_written < bytes_read) {
+			bsdtar_warnc(bsdtar, 0, "%s", archive_error_string(a));
+			return (-1);
+		}
+		progress += bytes_written;
+		bytes_read = archive_read_data(ina, buff, sizeof(buff));
+	}
+
+	return (0);
+}
+
+/*
+ * Add the file or dir hierarchy named by 'path' to the archive
+ */
+static void
+write_hierarchy(struct bsdtar *bsdtar, struct archive *a, const char *path)
+{
+	struct tree *tree;
+	char symlink_mode = bsdtar->symlink_mode;
+	dev_t first_dev = 0;
+	int dev_recorded = 0;
+	int tree_ret;
+#ifdef __linux
+	int	 fd, r;
+	unsigned long fflags;
+#endif
+
+	tree = tree_open(path);
+
+	if (!tree) {
+		bsdtar_warnc(bsdtar, errno, "%s: Cannot open", path);
+		bsdtar->return_value = 1;
+		return;
+	}
+
+	while ((tree_ret = tree_next(tree))) {
+		const char *name = tree_current_path(tree);
+		const struct stat *st = NULL, *lst = NULL;
+		int descend;
+
+		if (tree_ret == TREE_ERROR_DIR)
+			bsdtar_warnc(bsdtar, errno, "%s: Couldn't visit directory", name);
+		if (tree_ret != TREE_REGULAR)
+			continue;
+		lst = tree_current_lstat(tree);
+		if (lst == NULL) {
+			/* Couldn't lstat(); must not exist. */
+			bsdtar_warnc(bsdtar, errno, "%s: Cannot stat", name);
+
+			/*
+			 * Report an error via the exit code if the failed
+			 * path is a prefix of what the user provided via
+			 * the command line.  (Testing for string equality
+			 * here won't work due to trailing '/' characters.)
+			 */
+			if (memcmp(name, path, strlen(name)) == 0)
+				bsdtar->return_value = 1;
+
+			continue;
+		}
+		if (S_ISLNK(lst->st_mode))
+			st = tree_current_stat(tree);
+		/* Default: descend into any dir or symlink to dir. */
+		/* We'll adjust this later on. */
+		descend = 0;
+		if ((st != NULL) && S_ISDIR(st->st_mode))
+			descend = 1;
+		if ((lst != NULL) && S_ISDIR(lst->st_mode))
+			descend = 1;
+
+		/*
+		 * If user has asked us not to cross mount points,
+		 * then don't descend into into a dir on a different
+		 * device.
+		 */
+		if (!dev_recorded) {
+			first_dev = lst->st_dev;
+			dev_recorded = 1;
+		}
+		if (bsdtar->option_dont_traverse_mounts) {
+			if (lst != NULL && lst->st_dev != first_dev)
+				descend = 0;
+		}
+
+		/*
+		 * If this file/dir is flagged "nodump" and we're
+		 * honoring such flags, skip this file/dir.
+		 */
+#ifdef HAVE_CHFLAGS
+		if (bsdtar->option_honor_nodump &&
+		    (lst->st_flags & UF_NODUMP))
+			continue;
+#endif
+
+#ifdef __linux
+		/*
+		 * Linux has a nodump flag too but to read it
+		 * we have to open() the file/dir and do an ioctl on it...
+		 */
+		if (bsdtar->option_honor_nodump &&
+		    ((fd = open(name, O_RDONLY|O_NONBLOCK)) >= 0) &&
+		    ((r = ioctl(fd, EXT2_IOC_GETFLAGS, &fflags)),
+			close(fd), r) >= 0 &&
+		    (fflags & EXT2_NODUMP_FL))
+			continue;
+#endif
+
+		/*
+		 * If this file/dir is excluded by a filename
+		 * pattern, skip it.
+		 */
+		if (excluded(bsdtar, name))
+			continue;
+
+		/*
+		 * If the user vetoes this file/directory, skip it.
+		 */
+		if (bsdtar->option_interactive &&
+		    !yes("add '%s'", name))
+			continue;
+
+		/*
+		 * If this is a dir, decide whether or not to recurse.
+		 */
+		if (bsdtar->option_no_subdirs)
+			descend = 0;
+
+		/*
+		 * Distinguish 'L'/'P'/'H' symlink following.
+		 */
+		switch(symlink_mode) {
+		case 'H':
+			/* 'H': After the first item, rest like 'P'. */
+			symlink_mode = 'P';
+			/* 'H': First item (from command line) like 'L'. */
+			/* FALLTHROUGH */
+		case 'L':
+			/* 'L': Do descend through a symlink to dir. */
+			/* 'L': Archive symlink to file as file. */
+			lst = tree_current_stat(tree);
+			/* If stat fails, we have a broken symlink;
+			 * in that case, archive the link as such. */
+			if (lst == NULL)
+				lst = tree_current_lstat(tree);
+			break;
+		default:
+			/* 'P': Don't descend through a symlink to dir. */
+			if (!S_ISDIR(lst->st_mode))
+				descend = 0;
+			/* 'P': Archive symlink to file as symlink. */
+			/* lst = tree_current_lstat(tree); */
+			break;
+		}
+
+		if (descend)
+			tree_descend(tree);
+
+		/*
+		 * Write the entry.  Note that write_entry() handles
+		 * pathname editing and newness testing.
+		 */
+		write_entry(bsdtar, a, lst, name,
+		    tree_current_access_path(tree));
+	}
+	tree_close(tree);
+}
+
+/*
+ * Backend for write_entry.
+ */
+static void
+write_entry_backend(struct bsdtar *bsdtar, struct archive *a,
+    struct archive_entry *entry, int fd)
+{
+	int e;
+
+	if (fd == -1 && archive_entry_size(entry) > 0) {
+		const char *pathname = archive_entry_sourcepath(entry);
+		fd = open(pathname, O_RDONLY);
+		if (fd == -1) {
+			if (!bsdtar->verbose)
+				bsdtar_warnc(bsdtar, errno,
+				    "%s: could not open file", pathname);
+			else
+				fprintf(stderr, ": %s", strerror(errno));
+			return;
+		}
+	}
+
+	e = archive_write_header(a, entry);
+	if (e != ARCHIVE_OK) {
+		if (!bsdtar->verbose)
+			bsdtar_warnc(bsdtar, 0, "%s: %s",
+			    archive_entry_pathname(entry),
+			    archive_error_string(a));
+		else
+			fprintf(stderr, ": %s", archive_error_string(a));
+	}
+
+	if (e == ARCHIVE_FATAL)
+		exit(1);
+
+	/*
+	 * If we opened a file earlier, write it out now.  Note that
+	 * the format handler might have reset the size field to zero
+	 * to inform us that the archive body won't get stored.  In
+	 * that case, just skip the write.
+	 */
+	if (e >= ARCHIVE_WARN && fd >= 0 && archive_entry_size(entry) > 0) {
+		if (write_file_data(bsdtar, a, fd))
+			exit(1);
+		close(fd);
+	}
+}
+
+/*
+ * Add a single filesystem object to the archive.
+ */
+static void
+write_entry(struct bsdtar *bsdtar, struct archive *a, const struct stat *st,
+    const char *pathname, const char *accpath)
+{
+	struct archive_entry	*entry, *sparse_entry;
+	int			fd;
+#ifdef __linux
+	int			 r;
+	unsigned long		 stflags;
+#endif
+	static char		 linkbuffer[PATH_MAX+1];
+
+	fd = -1;
+	entry = archive_entry_new();
+
+	archive_entry_set_pathname(entry, pathname);
+	archive_entry_copy_sourcepath(entry, accpath);
+
+	/*
+	 * Rewrite the pathname to be archived.  If rewrite
+	 * fails, skip the entry.
+	 */
+	if (edit_pathname(bsdtar, entry))
+		goto abort;
+
+	/*
+	 * In -u mode, check that the file is newer than what's
+	 * already in the archive; in all modes, obey --newerXXX flags.
+	 */
+	if (!new_enough(bsdtar, archive_entry_pathname(entry), st))
+		goto abort;
+
+	/* Display entry as we process it. This format is required by SUSv2. */
+	if (bsdtar->verbose)
+		safe_fprintf(stderr, "a %s", archive_entry_pathname(entry));
+
+	/* Read symbolic link information. */
+	if ((st->st_mode & S_IFMT) == S_IFLNK) {
+		int lnklen;
+
+		lnklen = readlink(accpath, linkbuffer, PATH_MAX);
+		if (lnklen < 0) {
+			if (!bsdtar->verbose)
+				bsdtar_warnc(bsdtar, errno,
+				    "%s: Couldn't read symbolic link",
+				    pathname);
+			else
+				safe_fprintf(stderr,
+				    ": Couldn't read symbolic link: %s",
+				    strerror(errno));
+			goto cleanup;
+		}
+		linkbuffer[lnklen] = 0;
+		archive_entry_set_symlink(entry, linkbuffer);
+	}
+
+	/* Look up username and group name. */
+	archive_entry_set_uname(entry, lookup_uname(bsdtar, st->st_uid));
+	archive_entry_set_gname(entry, lookup_gname(bsdtar, st->st_gid));
+
+#ifdef HAVE_CHFLAGS
+	if (st->st_flags != 0)
+		archive_entry_set_fflags(entry, st->st_flags, 0);
+#endif
+
+#ifdef __linux
+	if ((S_ISREG(st->st_mode) || S_ISDIR(st->st_mode)) &&
+	    ((fd = open(accpath, O_RDONLY|O_NONBLOCK)) >= 0) &&
+	    ((r = ioctl(fd, EXT2_IOC_GETFLAGS, &stflags)), close(fd), (fd = -1), r) >= 0 &&
+	    stflags) {
+		archive_entry_set_fflags(entry, stflags, 0);
+	}
+#endif
+
+	archive_entry_copy_stat(entry, st);
+	setup_acls(bsdtar, entry, accpath);
+	setup_xattrs(bsdtar, entry, accpath);
+
+	/* Non-regular files get archived with zero size. */
+	if (!S_ISREG(st->st_mode))
+		archive_entry_set_size(entry, 0);
+
+	/* Record what we're doing, for the benefit of SIGINFO / SIGUSR1. */
+	siginfo_setinfo(bsdtar, "adding", archive_entry_pathname(entry),
+	    archive_entry_size(entry));
+	archive_entry_linkify(bsdtar->resolver, &entry, &sparse_entry);
+
+	/* Handle SIGINFO / SIGUSR1 request if one was made. */
+	siginfo_printinfo(bsdtar, 0);
+
+	while (entry != NULL) {
+		write_entry_backend(bsdtar, a, entry, fd);
+		fd = -1;
+		archive_entry_free(entry);
+		entry = sparse_entry;
+		sparse_entry = NULL;
+	}
+
+cleanup:
+	if (bsdtar->verbose)
+		fprintf(stderr, "\n");
+
+abort:
+	if (fd >= 0)
+		close(fd);
+
+	archive_entry_free(entry);
+}
+
+
+/* Helper function to copy file to archive, with stack-allocated buffer. */
+static int
+write_file_data(struct bsdtar *bsdtar, struct archive *a, int fd)
+{
+	char	buff[64*1024];
+	ssize_t	bytes_read;
+	ssize_t	bytes_written;
+	off_t	progress = 0;
+
+	/* XXX TODO: Allocate buffer on heap and store pointer to
+	 * it in bsdtar structure; arrange cleanup as well. XXX */
+
+	bytes_read = read(fd, buff, sizeof(buff));
+	while (bytes_read > 0) {
+		siginfo_printinfo(bsdtar, progress);
+
+		bytes_written = archive_write_data(a, buff, bytes_read);
+		if (bytes_written < 0) {
+			/* Write failed; this is bad */
+			bsdtar_warnc(bsdtar, 0, "%s", archive_error_string(a));
+			return (-1);
+		}
+		if (bytes_written < bytes_read) {
+			/* Write was truncated; warn but continue. */
+			bsdtar_warnc(bsdtar, 0,
+			    "Truncated write; file may have grown while being archived.");
+			return (0);
+		}
+		progress += bytes_written;
+		bytes_read = read(fd, buff, sizeof(buff));
+	}
+	return 0;
+}
+
+
+static void
+create_cleanup(struct bsdtar *bsdtar)
+{
+	free_cache(bsdtar->uname_cache);
+	bsdtar->uname_cache = NULL;
+	free_cache(bsdtar->gname_cache);
+	bsdtar->gname_cache = NULL;
+}
+
+#ifdef HAVE_POSIX_ACL
+static void		setup_acl(struct bsdtar *bsdtar,
+			     struct archive_entry *entry, const char *accpath,
+			     int acl_type, int archive_entry_acl_type);
+
+static void
+setup_acls(struct bsdtar *bsdtar, struct archive_entry *entry,
+    const char *accpath)
+{
+	archive_entry_acl_clear(entry);
+
+	setup_acl(bsdtar, entry, accpath,
+	    ACL_TYPE_ACCESS, ARCHIVE_ENTRY_ACL_TYPE_ACCESS);
+	/* Only directories can have default ACLs. */
+	if (S_ISDIR(archive_entry_mode(entry)))
+		setup_acl(bsdtar, entry, accpath,
+		    ACL_TYPE_DEFAULT, ARCHIVE_ENTRY_ACL_TYPE_DEFAULT);
+}
+
+static void
+setup_acl(struct bsdtar *bsdtar, struct archive_entry *entry,
+    const char *accpath, int acl_type, int archive_entry_acl_type)
+{
+	acl_t		 acl;
+	acl_tag_t	 acl_tag;
+	acl_entry_t	 acl_entry;
+	acl_permset_t	 acl_permset;
+	int		 s, ae_id, ae_tag, ae_perm;
+	const char	*ae_name;
+
+	/* Retrieve access ACL from file. */
+	acl = acl_get_file(accpath, acl_type);
+	if (acl != NULL) {
+		s = acl_get_entry(acl, ACL_FIRST_ENTRY, &acl_entry);
+		while (s == 1) {
+			ae_id = -1;
+			ae_name = NULL;
+
+			acl_get_tag_type(acl_entry, &acl_tag);
+			if (acl_tag == ACL_USER) {
+				ae_id = (int)*(uid_t *)acl_get_qualifier(acl_entry);
+				ae_name = lookup_uname(bsdtar, ae_id);
+				ae_tag = ARCHIVE_ENTRY_ACL_USER;
+			} else if (acl_tag == ACL_GROUP) {
+				ae_id = (int)*(gid_t *)acl_get_qualifier(acl_entry);
+				ae_name = lookup_gname(bsdtar, ae_id);
+				ae_tag = ARCHIVE_ENTRY_ACL_GROUP;
+			} else if (acl_tag == ACL_MASK) {
+				ae_tag = ARCHIVE_ENTRY_ACL_MASK;
+			} else if (acl_tag == ACL_USER_OBJ) {
+				ae_tag = ARCHIVE_ENTRY_ACL_USER_OBJ;
+			} else if (acl_tag == ACL_GROUP_OBJ) {
+				ae_tag = ARCHIVE_ENTRY_ACL_GROUP_OBJ;
+			} else if (acl_tag == ACL_OTHER) {
+				ae_tag = ARCHIVE_ENTRY_ACL_OTHER;
+			} else {
+				/* Skip types that libarchive can't support. */
+				continue;
+			}
+
+			acl_get_permset(acl_entry, &acl_permset);
+			ae_perm = 0;
+			/*
+			 * acl_get_perm() is spelled differently on different
+			 * platforms; see bsdtar_platform.h for details.
+			 */
+			if (ACL_GET_PERM(acl_permset, ACL_EXECUTE))
+				ae_perm |= ARCHIVE_ENTRY_ACL_EXECUTE;
+			if (ACL_GET_PERM(acl_permset, ACL_READ))
+				ae_perm |= ARCHIVE_ENTRY_ACL_READ;
+			if (ACL_GET_PERM(acl_permset, ACL_WRITE))
+				ae_perm |= ARCHIVE_ENTRY_ACL_WRITE;
+
+			archive_entry_acl_add_entry(entry,
+			    archive_entry_acl_type, ae_perm, ae_tag,
+			    ae_id, ae_name);
+
+			s = acl_get_entry(acl, ACL_NEXT_ENTRY, &acl_entry);
+		}
+		acl_free(acl);
+	}
+}
+#else
+static void
+setup_acls(struct bsdtar *bsdtar, struct archive_entry *entry,
+    const char *accpath)
+{
+	(void)bsdtar;
+	(void)entry;
+	(void)accpath;
+}
+#endif
+
+#if HAVE_LISTXATTR && HAVE_LLISTXATTR && HAVE_GETXATTR && HAVE_LGETXATTR
+
+static void
+setup_xattr(struct bsdtar *bsdtar, struct archive_entry *entry,
+    const char *accpath, const char *name)
+{
+	size_t size;
+	void *value = NULL;
+	char symlink_mode = bsdtar->symlink_mode;
+
+	if (symlink_mode == 'H')
+		size = getxattr(accpath, name, NULL, 0);
+	else
+		size = lgetxattr(accpath, name, NULL, 0);
+
+	if (size == -1) {
+		bsdtar_warnc(bsdtar, errno, "Couldn't get extended attribute");
+		return;
+	}
+
+	if (size > 0 && (value = malloc(size)) == NULL) {
+		bsdtar_errc(bsdtar, 1, errno, "Out of memory");
+		return;
+	}
+
+	if (symlink_mode == 'H')
+		size = getxattr(accpath, name, value, size);
+	else
+		size = lgetxattr(accpath, name, value, size);
+
+	if (size == -1) {
+		bsdtar_warnc(bsdtar, errno, "Couldn't get extended attribute");
+		return;
+	}
+
+	archive_entry_xattr_add_entry(entry, name, value, size);
+
+	free(value);
+}
+
+/*
+ * Linux extended attribute support
+ */
+static void
+setup_xattrs(struct bsdtar *bsdtar, struct archive_entry *entry,
+    const char *accpath)
+{
+	char *list, *p;
+	size_t list_size;
+	char symlink_mode = bsdtar->symlink_mode;
+
+	if (symlink_mode == 'H')
+		list_size = listxattr(accpath, NULL, 0);
+	else
+		list_size = llistxattr(accpath, NULL, 0);
+
+	if (list_size == -1) {
+		bsdtar_warnc(bsdtar, errno,
+			"Couldn't list extended attributes");
+		return;
+	} else if (list_size == 0)
+		return;
+
+	if ((list = malloc(list_size)) == NULL) {
+		bsdtar_errc(bsdtar, 1, errno, "Out of memory");
+		return;
+	}
+
+	if (symlink_mode == 'H')
+		list_size = listxattr(accpath, list, list_size);
+	else
+		list_size = llistxattr(accpath, list, list_size);
+
+	if (list_size == -1) {
+		bsdtar_warnc(bsdtar, errno,
+			"Couldn't list extended attributes");
+		free(list);
+		return;
+	}
+
+	for (p = list; (p - list) < list_size; p += strlen(p) + 1) {
+		if (strncmp(p, "system.", 7) == 0 ||
+				strncmp(p, "xfsroot.", 8) == 0)
+			continue;
+
+		setup_xattr(bsdtar, entry, accpath, p);
+	}
+
+	free(list);
+}
+
+#else
+
+/*
+ * Generic (stub) extended attribute support.
+ */
+static void
+setup_xattrs(struct bsdtar *bsdtar, struct archive_entry *entry,
+    const char *accpath)
+{
+	(void)bsdtar; /* UNUSED */
+	(void)entry; /* UNUSED */
+	(void)accpath; /* UNUSED */
+}
+
+#endif
+
+static void
+free_cache(struct name_cache *cache)
+{
+	size_t i;
+
+	if (cache != NULL) {
+		for (i = 0; i < cache->size; i++) {
+			if (cache->cache[i].name != NULL &&
+			    cache->cache[i].name != NO_NAME)
+				free((void *)(uintptr_t)cache->cache[i].name);
+		}
+		free(cache);
+	}
+}
+
+/*
+ * Lookup uid/gid from uname/gname, return NULL if no match.
+ */
+static const char *
+lookup_name(struct bsdtar *bsdtar, struct name_cache **name_cache_variable,
+    int (*lookup_fn)(struct bsdtar *, const char **, id_t), id_t id)
+{
+	struct name_cache	*cache;
+	const char *name;
+	int slot;
+
+
+	if (*name_cache_variable == NULL) {
+		*name_cache_variable = malloc(sizeof(struct name_cache));
+		if (*name_cache_variable == NULL)
+			bsdtar_errc(bsdtar, 1, ENOMEM, "No more memory");
+		memset(*name_cache_variable, 0, sizeof(struct name_cache));
+		(*name_cache_variable)->size = name_cache_size;
+	}
+
+	cache = *name_cache_variable;
+	cache->probes++;
+
+	slot = id % cache->size;
+	if (cache->cache[slot].name != NULL) {
+		if (cache->cache[slot].id == id) {
+			cache->hits++;
+			if (cache->cache[slot].name == NO_NAME)
+				return (NULL);
+			return (cache->cache[slot].name);
+		}
+		if (cache->cache[slot].name != NO_NAME)
+			free((void *)(uintptr_t)cache->cache[slot].name);
+		cache->cache[slot].name = NULL;
+	}
+
+	if (lookup_fn(bsdtar, &name, id) == 0) {
+		if (name == NULL || name[0] == '\0') {
+			/* Cache the negative response. */
+			cache->cache[slot].name = NO_NAME;
+			cache->cache[slot].id = id;
+		} else {
+			cache->cache[slot].name = strdup(name);
+			if (cache->cache[slot].name != NULL) {
+				cache->cache[slot].id = id;
+				return (cache->cache[slot].name);
+			}
+			/*
+			 * Conveniently, NULL marks an empty slot, so
+			 * if the strdup() fails, we've just failed to
+			 * cache it.  No recovery necessary.
+			 */
+		}
+	}
+	return (NULL);
+}
+
+static const char *
+lookup_uname(struct bsdtar *bsdtar, uid_t uid)
+{
+	return (lookup_name(bsdtar, &bsdtar->uname_cache,
+		    &lookup_uname_helper, (id_t)uid));
+}
+
+static int
+lookup_uname_helper(struct bsdtar *bsdtar, const char **name, id_t id)
+{
+	struct passwd	*pwent;
+
+	(void)bsdtar; /* UNUSED */
+
+	errno = 0;
+	pwent = getpwuid((uid_t)id);
+	if (pwent == NULL) {
+		*name = NULL;
+		if (errno != 0)
+			bsdtar_warnc(bsdtar, errno, "getpwuid(%d) failed", id);
+		return (errno);
+	}
+
+	*name = pwent->pw_name;
+	return (0);
+}
+
+static const char *
+lookup_gname(struct bsdtar *bsdtar, gid_t gid)
+{
+	return (lookup_name(bsdtar, &bsdtar->gname_cache,
+		    &lookup_gname_helper, (id_t)gid));
+}
+
+static int
+lookup_gname_helper(struct bsdtar *bsdtar, const char **name, id_t id)
+{
+	struct group	*grent;
+
+	(void)bsdtar; /* UNUSED */
+
+	errno = 0;
+	grent = getgrgid((gid_t)id);
+	if (grent == NULL) {
+		*name = NULL;
+		if (errno != 0)
+			bsdtar_warnc(bsdtar, errno, "getgrgid(%d) failed", id);
+		return (errno);
+	}
+
+	*name = grent->gr_name;
+	return (0);
+}
+
+/*
+ * Test if the specified file is new enough to include in the archive.
+ */
+int
+new_enough(struct bsdtar *bsdtar, const char *path, const struct stat *st)
+{
+	struct archive_dir_entry *p;
+
+	/*
+	 * If this file/dir is excluded by a time comparison, skip it.
+	 */
+	if (bsdtar->newer_ctime_sec > 0) {
+		if (st->st_ctime < bsdtar->newer_ctime_sec)
+			return (0); /* Too old, skip it. */
+		if (st->st_ctime == bsdtar->newer_ctime_sec
+		    && ARCHIVE_STAT_CTIME_NANOS(st)
+		    <= bsdtar->newer_ctime_nsec)
+			return (0); /* Too old, skip it. */
+	}
+	if (bsdtar->newer_mtime_sec > 0) {
+		if (st->st_mtime < bsdtar->newer_mtime_sec)
+			return (0); /* Too old, skip it. */
+		if (st->st_mtime == bsdtar->newer_mtime_sec
+		    && ARCHIVE_STAT_MTIME_NANOS(st)
+		    <= bsdtar->newer_mtime_nsec)
+			return (0); /* Too old, skip it. */
+	}
+
+	/*
+	 * In -u mode, we only write an entry if it's newer than
+	 * what was already in the archive.
+	 */
+	if (bsdtar->archive_dir != NULL &&
+	    bsdtar->archive_dir->head != NULL) {
+		for (p = bsdtar->archive_dir->head; p != NULL; p = p->next) {
+			if (pathcmp(path, p->name)==0)
+				return (p->mtime_sec < st->st_mtime ||
+				    (p->mtime_sec == st->st_mtime &&
+					p->mtime_nsec
+					< ARCHIVE_STAT_MTIME_NANOS(st)));
+		}
+	}
+
+	/* If the file wasn't rejected, include it. */
+	return (1);
+}
+
+/*
+ * Add an entry to the dir list for 'u' mode.
+ *
+ * XXX TODO: Make this fast.
+ */
+static void
+add_dir_list(struct bsdtar *bsdtar, const char *path,
+    time_t mtime_sec, int mtime_nsec)
+{
+	struct archive_dir_entry	*p;
+
+	/*
+	 * Search entire list to see if this file has appeared before.
+	 * If it has, override the timestamp data.
+	 */
+	p = bsdtar->archive_dir->head;
+	while (p != NULL) {
+		if (strcmp(path, p->name)==0) {
+			p->mtime_sec = mtime_sec;
+			p->mtime_nsec = mtime_nsec;
+			return;
+		}
+		p = p->next;
+	}
+
+	p = malloc(sizeof(*p));
+	if (p == NULL)
+		bsdtar_errc(bsdtar, 1, ENOMEM, "Can't read archive directory");
+
+	p->name = strdup(path);
+	if (p->name == NULL)
+		bsdtar_errc(bsdtar, 1, ENOMEM, "Can't read archive directory");
+	p->mtime_sec = mtime_sec;
+	p->mtime_nsec = mtime_nsec;
+	p->next = NULL;
+	if (bsdtar->archive_dir->tail == NULL) {
+		bsdtar->archive_dir->head = bsdtar->archive_dir->tail = p;
+	} else {
+		bsdtar->archive_dir->tail->next = p;
+		bsdtar->archive_dir->tail = p;
+	}
+}
+
+void
+test_for_append(struct bsdtar *bsdtar)
+{
+	struct stat s;
+
+	if (*bsdtar->argv == NULL && bsdtar->names_from_file == NULL)
+		bsdtar_errc(bsdtar, 1, 0, "no files or directories specified");
+	if (bsdtar->filename == NULL)
+		bsdtar_errc(bsdtar, 1, 0, "Cannot append to stdout.");
+
+	if (bsdtar->create_compression != 0)
+		bsdtar_errc(bsdtar, 1, 0,
+		    "Cannot append to %s with compression", bsdtar->filename);
+
+	if (stat(bsdtar->filename, &s) != 0)
+		return;
+
+	if (!S_ISREG(s.st_mode) && !S_ISBLK(s.st_mode))
+		bsdtar_errc(bsdtar, 1, 0,
+		    "Cannot append to %s: not a regular file.",
+		    bsdtar->filename);
+}