/* SPDX-License-Identifier: GPL-3.0-or-later */
#ifndef TAR_H
#define TAR_H

#include <sys/stat.h>
#include <stdbool.h>

typedef struct {
	char name[100];
	char mode[8];
	char uid[8];
	char gid[8];
	char size[12];
	char mtime[12];
	char chksum[8];
	char typeflag;
	char linkname[100];
	char magic[6];
	char version[2];
	char uname[32];
	char gname[32];
	char devmajor[8];
	char devminor[8];
	char prefix[155];
	char padding[12];
} tar_header_t;

typedef struct {
	struct stat sb;
	char *name;
	char *link_target;
	bool unknown_record;
} tar_header_decoded_t;

#define TAR_TYPE_FILE '0'
#define TAR_TYPE_LINK '1'
#define TAR_TYPE_SLINK '2'
#define TAR_TYPE_CHARDEV '3'
#define TAR_TYPE_BLOCKDEV '4'
#define TAR_TYPE_DIR '5'
#define TAR_TYPE_FIFO '6'

#define TAR_TYPE_PAX 'x'

#define TAR_MAGIC "ustar"
#define TAR_VERSION "00"

/*
  Returns < 0 on failure, > 0 if cannot encode, 0 on success.
  Prints error/warning messages to stderr.
*/
int write_tar_header(int fd, const struct stat *sb, const char *name,
		     const char *slink_target);

/* calcuate and skip the zero padding */
int skip_padding(int fd, uint64_t size);

/* round up to block size and skip the entire entry */
int skip_entry(int fd, uint64_t size);

int read_header(int fd, tar_header_decoded_t *out);

void clear_header(tar_header_decoded_t *hdr);

#endif /* TAR_H */