3 files changed, 43 insertions, 3 deletions
diff --git a/lib/tar/Makemodule.am b/lib/tar/Makemodule.am
index 42f11ae..129d66f 100644
--- a/lib/tar/Makemodule.am
+++ b/lib/tar/Makemodule.am
@@ -2,7 +2,7 @@ libtar_a_SOURCES = lib/tar/read_header.c lib/tar/write_header.c lib/tar/skip.c
 libtar_a_SOURCES += lib/tar/number.c lib/tar/checksum.c lib/tar/cleanup.c
 libtar_a_SOURCES += lib/tar/read_sparse_map.c lib/tar/read_sparse_map_old.c
 libtar_a_SOURCES += lib/tar/base64.c lib/tar/urldecode.c lib/tar/internal.h
-libtar_a_SOURCES += include/tar.h
+libtar_a_SOURCES += lib/tar/padd_file.c include/tar.h
 libtar_a_CFLAGS = $(AM_CFLAGS)
 libtar_a_CPPFLAGS = $(AM_CPPFLAGS)
 
diff --git a/lib/tar/padd_file.c b/lib/tar/padd_file.c
new file mode 100644
index 0000000..471370d
--- /dev/null
+++ b/lib/tar/padd_file.c
@@ -0,0 +1,40 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * padd_file.c
+ *
+ * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
+ */
+#include "config.h"
+#include "tar.h"
+
+#include <stdlib.h>
+#include <stdio.h>
+
+int padd_file(int outfd, sqfs_u64 size)
+{
+	size_t padd_sz = size % TAR_RECORD_SIZE;
+	int status = -1;
+	sqfs_u8 *buffer;
+
+	if (padd_sz == 0)
+		return 0;
+
+	padd_sz = TAR_RECORD_SIZE - padd_sz;
+
+	buffer = calloc(1, padd_sz);
+	if (buffer == NULL)
+		goto fail_errno;
+
+	if (write_data("padding output file to block size",
+		       outfd, buffer, padd_sz)) {
+		goto out;
+	}
+
+	status = 0;
+out:
+	free(buffer);
+	return status;
+fail_errno:
+	perror("padding output file to block size");
+	goto out;
+}
diff --git a/lib/tar/write_header.c b/lib/tar/write_header.c
index 4c8caa2..14802c0 100644
--- a/lib/tar/write_header.c
+++ b/lib/tar/write_header.c
@@ -109,7 +109,7 @@ static int write_gnu_header(int fd, const struct stat *orig,
 		return -1;
 	}
 
-	return padd_file(fd, payload_len, 512);
+	return padd_file(fd, payload_len);
 }
 
 static size_t num_digits(size_t num)
@@ -152,7 +152,7 @@ static int write_schily_xattr(int fd, const struct stat *orig,
 		dprintf(fd, "%zu %s%s=%s\n", len, prefix, it->key, it->value);
 	}
 
-	return padd_file(fd, total_size, 512);
+	return padd_file(fd, total_size);
 }
 
 int write_tar_header(int fd, const struct stat *sb, const char *name,