[git commit] tar: ignore file size (assume 0) for hardlinks

[Denys Vlasenko]

commit: http://git.busybox.net/busybox/commit/?id=954dbd3a004dcb8df7e1e7283c4e249e02a300a4
branch: http://git.busybox.net/busybox/commit/?id=refs/heads/master

Signed-off-by: Ian Wienand <ianw at vmware.com>
Signed-off-by: Denys Vlasenko <vda.linux at googlemail.com>
---
 archival/libarchive/get_header_tar.c |   16 +++++++++++++---
 1 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/archival/libarchive/get_header_tar.c b/archival/libarchive/get_header_tar.c
index f73cd33..79caff5 100644
--- a/archival/libarchive/get_header_tar.c
+++ b/archival/libarchive/get_header_tar.c
@@ -348,10 +348,20 @@ char FAST_FUNC get_header_tar(archive_handle_t *archive_handle)
 	/* Set bits 12-15 of the files mode */
 	/* (typeflag was not trashed because chksum does not use getOctal) */
 	switch (tar.typeflag) {
-	/* busybox identifies hard links as being regular files with 0 size and a link name */
-	case '1':
+	case '1': /* hardlink */
+		/* we mark hardlinks as regular files with zero size and a link name */
 		file_header->mode |= S_IFREG;
-		break;
+		/* on size of link fields from star(4)
+		 * ... For tar archives written by pre POSIX.1-1988
+		 * implementations, the size field usually contains the size of
+		 * the file and needs to be ignored as no data may follow this
+		 * header type.  For POSIX.1- 1988 compliant archives, the size
+		 * field needs to be 0.  For POSIX.1-2001 compliant archives,
+		 * the size field may be non zero, indicating that file data is
+		 * included in the archive.
+		 * i.e; always assume this is zero for safety.
+		 */
+		goto size0;
 	case '7':
 	/* case 0: */
 	case '0':
-- 
1.7.3.4