file/src/tar.h

/*
 * Copyright (c) Ian F. Darwin 1986-1995.
 * Software written by Ian F. Darwin and others;
 * maintained 1995-present by Christos Zoulas and others.
 *
 * 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 immediately at the beginning of the file, without modification,
 *    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 AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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.
 */
/*
 * Header file for public domain tar (tape archive) program.
 *
 * @(#)tar.h 1.20 86/10/29	Public Domain.
 *
 * Created 25 August 1985 by John Gilmore, ihnp4!hoptoad!gnu.
 *
 * $File: tar.h,v 1.13 2010/11/30 14:58:53 rrt Exp $ # checkin only
 */

/*
 * Header block on tape.
 *
 * I'm going to use traditional DP naming conventions here.
 * A "block" is a big chunk of stuff that we do I/O on.
 * A "record" is a piece of info that we care about.
 * Typically many "record"s fit into a "block".
 */
#define	RECORDSIZE	512
#define	NAMSIZ	100
#define	TUNMLEN	32
#define	TGNMLEN	32

union record {
	unsigned char	charptr[RECORDSIZE];
	struct header {
		char	name[NAMSIZ];
		char	mode[8];
		char	uid[8];
		char	gid[8];
		char	size[12];
		char	mtime[12];
		char	chksum[8];
		char	linkflag;
		char	linkname[NAMSIZ];
		char	magic[8];
		char	uname[TUNMLEN];
		char	gname[TGNMLEN];
		char	devmajor[8];
		char	devminor[8];
	} header;
};

/* The magic field is filled with this if uname and gname are valid. */
#define	TMAGIC		"ustar"		/* 5 chars and a null */
#define	GNUTMAGIC	"ustar  "	/* 7 chars and a null */