non-recursive extract and list

Sometimes it makes sense to extract or list a directory contained in
an archive without also doing the same for the content of the
directory, i.e. allowing -n (= --no-recursion) in combination with the
x and t modes.

bsdtar uses the match functionality in libarchive to track include
matches. A new libarchive API call
archive_match_set_inclusion_recursion() gets introduced to
influence the matching behavior, with the default behavior as before.

Non-recursive matching can be achieved by anchoring the path match at
both start and end. Asking for a directory which itself isn't in the
archive when in non-recursive mode is an error and handled by the
existing mechanism for tracking unused inclusion entries.

1 files changed, 10 insertions, 2 deletions

diff --git a/tar/bsdtar.c b/tar/bsdtar.c
index 280a0a16..b59963d0 100644
--- a/tar/bsdtar.c
+++ b/tar/bsdtar.c
@@ -839,8 +839,6 @@ main(int argc, char **argv)
 			break;
 		}
 	}
-	if (bsdtar->flags & OPTFLAG_NO_SUBDIRS)
-		only_mode(bsdtar, "-n", "cru");
 	if (bsdtar->flags & OPTFLAG_STDOUT)
 		only_mode(bsdtar, "-O", "xt");
 	if (bsdtar->flags & OPTFLAG_UNLINK_FIRST)
@@ -890,6 +888,16 @@ main(int argc, char **argv)
 		only_mode(bsdtar, buff, "cru");
 	}
 
+	/*
+	 * When creating an archive from a directory tree, the directory
+	 * walking code will already avoid entering directories when
+	 * recursive inclusion of directory content is disabled, therefore
+	 * changing the matching behavior has no effect for creation modes.
+	 * It is relevant for extraction or listing.
+	 */
+	archive_match_set_inclusion_recursion(bsdtar->matching,
+					      !(bsdtar->flags & OPTFLAG_NO_SUBDIRS));
+
 	/* Filename "-" implies stdio. */
 	if (strcmp(bsdtar->filename, "-") == 0)
 		bsdtar->filename = NULL;