/*
**  Copyright 1998-2003 University of Illinois Board of Trustees
**  Copyright 1998-2003 Mark D. Roth
**  All rights reserved.
**
**  libtar.h - header file for libtar library
**
**  Mark D. Roth <roth@uiuc.edu>
**  Campus Information Technologies and Educational Services
**  University of Illinois at Urbana-Champaign
*/

#ifndef LIBTAR_H
#define LIBTAR_H

#include <sys/types.h>
#include <sys/stat.h>
#include <libtar/tar.h>

#include <libtar/libtar_listhash.h>
#include <libtar/compat.h>
#ifdef __cplusplus
extern "C" {
#endif


/* useful constants */
#define T_BLOCKSIZE    512
#define T_NAMELEN    100
#define T_PREFIXLEN    155
#define T_MAXPATHLEN    (T_NAMELEN + T_PREFIXLEN)

/* GNU extensions for typeflag */
#define GNU_LONGNAME_TYPE  'L'
#define GNU_LONGLINK_TYPE  'K'

/* our version of the tar header structure */
struct tar_header
{
  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];
  char *gnu_longname;
  char *gnu_longlink;
};


/***** handle.c ************************************************************/

typedef int (*openfunc_t)(void* call_data, const char *, int, mode_t);
typedef int (*closefunc_t)(void* call_data);
typedef ssize_t (*readfunc_t)(void* call_data, void *, size_t);
typedef ssize_t (*writefunc_t)(void* call_data, const void *, size_t);

typedef struct
{
  openfunc_t openfunc;
  closefunc_t closefunc;
  readfunc_t readfunc;
  writefunc_t writefunc;
  void* call_data;
}
tartype_t;

typedef struct
{
  tartype_t *type;
  char *pathname;
  int oflags;
  int options;
  struct tar_header th_buf;
  libtar_hash_t *h;
}
TAR;

/* constant values for the TAR options field */
#define TAR_GNU       1  /* use GNU extensions */
#define TAR_VERBOSE     2  /* output file info to stdout */
#define TAR_NOOVERWRITE     4  /* don't overwrite existing files */
#define TAR_IGNORE_EOT     8  /* ignore double zero blocks as EOF */
#define TAR_CHECK_MAGIC    16  /* check magic in file header */
#define TAR_CHECK_VERSION  32  /* check version in file header */
#define TAR_IGNORE_CRC    64  /* ignore CRC in file header */

/* this is obsolete - it's here for backwards-compatibility only */
#define TAR_IGNORE_MAGIC  0

extern const char libtar_version[];

/* open a new tarfile handle */
int tar_open(TAR **t, char *pathname, tartype_t *type,
       int oflags, int mode, int options);

/* make a tarfile handle out of a previously-opened descriptor */
int tar_fdopen(TAR **t, int fd, char *pathname, tartype_t *type,
         int oflags, int mode, int options);

/* close tarfile handle */
int tar_close(TAR *t);


/***** append.c ************************************************************/

/* forward declaration to appease the compiler */
struct tar_dev;

/* cleanup function */
void tar_dev_free(struct tar_dev *tdp);

/* Appends a file to the tar archive.
 * Arguments:
 *    t        = TAR handle to append to
 *    realname = path of file to append
 *    savename = name to save the file under in the archive
 */
int tar_append_file(TAR *t, char *realname, char *savename);

/* write EOF indicator */
int tar_append_eof(TAR *t);

/* add file contents to a tarchive */
int tar_append_regfile(TAR *t, char *realname);


/***** block.c *************************************************************/

/* macros for reading/writing tarchive blocks */
#define tar_block_read(t, buf) \
  (*((t)->type->readfunc))((t)->type->call_data, (char *)(buf), T_BLOCKSIZE)
#define tar_block_write(t, buf) \
  (*((t)->type->writefunc))((t)->type->call_data, (char *)(buf), T_BLOCKSIZE)

/* read/write a header block */
int th_read(TAR *t);
int th_write(TAR *t);


/***** decode.c ************************************************************/

/* determine file type */
#define TH_ISREG(t)  ((t)->th_buf.typeflag == REGTYPE \
       || (t)->th_buf.typeflag == AREGTYPE \
       || (t)->th_buf.typeflag == CONTTYPE \
       || (S_ISREG((mode_t)oct_to_int((t)->th_buf.mode)) \
           && (t)->th_buf.typeflag != LNKTYPE))
#define TH_ISLNK(t)  ((t)->th_buf.typeflag == LNKTYPE)
#define TH_ISSYM(t)  ((t)->th_buf.typeflag == SYMTYPE \
       || S_ISLNK((mode_t)oct_to_int((t)->th_buf.mode)))
#define TH_ISCHR(t)  ((t)->th_buf.typeflag == CHRTYPE \
       || S_ISCHR((mode_t)oct_to_int((t)->th_buf.mode)))
#define TH_ISBLK(t)  ((t)->th_buf.typeflag == BLKTYPE \
       || S_ISBLK((mode_t)oct_to_int((t)->th_buf.mode)))
#define TH_ISDIR(t)  ((t)->th_buf.typeflag == DIRTYPE \
       || S_ISDIR((mode_t)oct_to_int((t)->th_buf.mode)) \
       || ((t)->th_buf.typeflag == AREGTYPE \
           && ((t)->th_buf.name[strlen((t)->th_buf.name) - 1] == '/')))
#define TH_ISFIFO(t)  ((t)->th_buf.typeflag == FIFOTYPE \
       || S_ISFIFO((mode_t)oct_to_int((t)->th_buf.mode)))
#define TH_ISLONGNAME(t)  ((t)->th_buf.typeflag == GNU_LONGNAME_TYPE)
#define TH_ISLONGLINK(t)  ((t)->th_buf.typeflag == GNU_LONGLINK_TYPE)

/* decode tar header info */
#define th_get_crc(t) oct_to_int((t)->th_buf.chksum)
#define th_get_size(t) oct_to_int((t)->th_buf.size)
#define th_get_mtime(t) oct_to_int((t)->th_buf.mtime)
#define th_get_devmajor(t) oct_to_int((t)->th_buf.devmajor)
#define th_get_devminor(t) oct_to_int((t)->th_buf.devminor)
#define th_get_linkname(t) ((t)->th_buf.gnu_longlink \
                            ? (t)->th_buf.gnu_longlink \
                            : (t)->th_buf.linkname)
char *th_get_pathname(TAR *t);
mode_t th_get_mode(TAR *t);
uid_t th_get_uid(TAR *t);
gid_t th_get_gid(TAR *t);


/***** encode.c ************************************************************/

/* encode file info in th_header */
void th_set_type(TAR *t, mode_t mode);
void th_set_path(TAR *t, char *pathname);
void th_set_link(TAR *t, char *linkname);
void th_set_device(TAR *t, dev_t device);
void th_set_user(TAR *t, uid_t uid);
void th_set_group(TAR *t, gid_t gid);
void th_set_mode(TAR *t, mode_t fmode);
#define th_set_mtime(t, fmtime) \
  int_to_oct_nonull((int)(fmtime), (t)->th_buf.mtime, 12)
#define th_set_size(t, fsize) \
  int_to_oct_nonull((int)(fsize), (t)->th_buf.size, 12)

/* encode everything at once (except the pathname and linkname) */
void th_set_from_stat(TAR *t, struct stat *s);

/* encode magic, version, and crc - must be done after everything else is set */
void th_finish(TAR *t);


/***** extract.c ***********************************************************/

/* sequentially extract next file from t */
int tar_extract_file(TAR *t, char *realname);

/* extract different file types */
int tar_extract_dir(TAR *t, char *realname);
int tar_extract_hardlink(TAR *t, char *realname);
int tar_extract_symlink(TAR *t, char *realname);
int tar_extract_chardev(TAR *t, char *realname);
int tar_extract_blockdev(TAR *t, char *realname);
int tar_extract_fifo(TAR *t, char *realname);

/* for regfiles, we need to extract the content blocks as well */
int tar_extract_regfile(TAR *t, char *realname);
int tar_skip_regfile(TAR *t);


/***** output.c ************************************************************/

/* print the tar header */
void th_print(TAR *t);

/* print "ls -l"-like output for the file described by th */
void th_print_long_ls(TAR *t);


/***** util.c *************************************************************/

/* hashing function for pathnames */
int path_hashfunc(char *key, int numbuckets);

/* matching function for dev_t's */
int dev_match(dev_t *dev1, dev_t *dev2);

/* matching function for ino_t's */
int ino_match(ino_t *ino1, ino_t *ino2);

/* hashing function for dev_t's */
int dev_hash(dev_t *dev);

/* hashing function for ino_t's */
int ino_hash(ino_t *inode);

/* create any necessary dirs */
int mkdirhier(char *path);

/* calculate header checksum */
int th_crc_calc(TAR *t);
#define th_crc_ok(t) (th_get_crc(t) == th_crc_calc(t))

/* string-octal to integer conversion */
int oct_to_int(char *oct);

/* integer to NULL-terminated string-octal conversion */
#define int_to_oct(num, oct, octlen) \
  snprintf((oct), (octlen), "%*lo ", (octlen) - 2, (unsigned long)(num))

/* integer to string-octal conversion, no NULL */
void int_to_oct_nonull(int num, char *oct, size_t octlen);


/***** wrapper.c **********************************************************/

/* extract groups of files */
int tar_extract_glob(TAR *t, char *globname, char *prefix);
int tar_extract_all(TAR *t, char *prefix);

/* add a whole tree of files */
int tar_append_tree(TAR *t, char *realdir, char *savedir);


#ifdef __cplusplus
}
#endif

#endif /* ! LIBTAR_H */