feat(skipcpio): move cpio on-disk format into separate header

Preparation for reusing cpio archive definitions.
skipcpio's PROGRAM_VERSION_STRING is currently unused so drop it.

Signed-off-by: David Disseldorp <ddiss@suse.de>

Author: ddiss

skipcpio/skipcpio.c

@@ -17,38 +17,14 @@
    along with this program; If not, see <http://www.gnu.org/licenses/>.
 */
 
-#define PROGRAM_VERSION_STRING "1"
-
 #ifndef _GNU_SOURCE
 #define _GNU_SOURCE
 #endif
 
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
-
-#define CPIO_MAGIC "070701"
-#define CPIO_END "TRAILER!!!"
-#define CPIO_ENDLEN (sizeof(CPIO_END) - 1)
-
-#define CPIO_ALIGNMENT 4
-
-struct cpio_header {
-        char c_magic[6];
-        char c_ino[8];
-        char c_mode[8];
-        char c_uid[8];
-        char c_gid[8];
-        char c_nlink[8];
-        char c_mtime[8];
-        char c_filesize[8];
-        char c_dev_maj[8];
-        char c_dev_min[8];
-        char c_rdev_maj[8];
-        char c_rdev_min[8];
-        char c_namesize[8];
-        char c_chksum[8];
-} __attribute__((packed));
+#include "skipcpio.h"
 
 struct buf_struct {
         struct cpio_header h;
@@ -62,8 +38,6 @@ union buf_union {
 
 static union buf_union buf;
 
-#define ALIGN_UP(n, a) (((n) + (a) - 1) & (~((a) - 1)))
-
 int main(int argc, char **argv)
 {
         FILE *f;

skipcpio/skipcpio.h

@@ -0,0 +1,42 @@
+/*
+   Copyright (C) 2021 Harald Hoyer
+   Copyright (C) 2021 Red Hat, Inc.  All rights reserved.
+
+   This program is free software: you can redistribute it and/or modify
+   under the terms of the GNU Lesser General Public License as published by
+   the Free Software Foundation; either version 2.1 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful, but
+   WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public License
+   along with this program; If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#define CPIO_MAGIC "070701"
+#define CPIO_END "TRAILER!!!"
+#define CPIO_ENDLEN (sizeof(CPIO_END) - 1)
+
+#define CPIO_ALIGNMENT 4
+
+struct cpio_header {
+        char c_magic[6];
+        char c_ino[8];
+        char c_mode[8];
+        char c_uid[8];
+        char c_gid[8];
+        char c_nlink[8];
+        char c_mtime[8];
+        char c_filesize[8];
+        char c_dev_maj[8];
+        char c_dev_min[8];
+        char c_rdev_maj[8];
+        char c_rdev_min[8];
+        char c_namesize[8];
+        char c_chksum[8];
+} __attribute__((packed));
+
+#define ALIGN_UP(n, a) (((n) + (a) - 1) & (~((a) - 1)))