LCOM1920-T02G10

/*-

 * Copyright (c) 2003-2008 Tim Kientzle

 * All rights reserved.

 *

 * 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, 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(S) ``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(S) 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.

 *

 * $FreeBSD: head/lib/libarchive/archive_entry.h 201096 2009-12-28 02:41:27Z kientzle $

 */

#ifndef ARCHIVE_ENTRY_H_INCLUDED

#define        ARCHIVE_ENTRY_H_INCLUDED

/*

 * Note: archive_entry.h is for use outside of libarchive; the

 * configuration headers (config.h, archive_platform.h, etc.) are

 * purely internal.  Do NOT use HAVE_XXX configuration macros to

 * control the behavior of this header!  If you must conditionalize,

 * use predefined compiler and/or platform macros.

 */

#include <sys/types.h>

#include <stddef.h>  /* for wchar_t */

#include <time.h>

#if defined(_WIN32) && !defined(__CYGWIN__)

#include <windows.h>

#endif

/* Get appropriate definitions of standard POSIX-style types. */

/* These should match the types used in 'struct stat' */

#if defined(_WIN32) && !defined(__CYGWIN__)

#define        __LA_INT64_T        __int64

# if defined(__BORLANDC__)

#  define        __LA_UID_T        uid_t

#  define        __LA_GID_T        gid_t

#  define        __LA_DEV_T        dev_t

#  define        __LA_MODE_T        mode_t

# else

#  define        __LA_UID_T        short

#  define        __LA_GID_T        short

#  define        __LA_DEV_T        unsigned int

#  define        __LA_MODE_T        unsigned short

# endif

#else

#include <unistd.h>

#define        __LA_INT64_T        int64_t

#define        __LA_UID_T        uid_t

#define        __LA_GID_T        gid_t

#define        __LA_DEV_T        dev_t

#define        __LA_MODE_T        mode_t

#endif

/*

 * XXX Is this defined for all Windows compilers?  If so, in what

 * header?  It would be nice to remove the __LA_INO_T indirection and

 * just use plain ino_t everywhere.  Likewise for the other types just

 * above.

 */

#define        __LA_INO_T        ino_t

/*

 * On Windows, define LIBARCHIVE_STATIC if you're building or using a

 * .lib.  The default here assumes you're building a DLL.  Only

 * libarchive source should ever define __LIBARCHIVE_BUILD.

 */

#if ((defined __WIN32__) || (defined _WIN32) || defined(__CYGWIN__)) && (!defined LIBARCHIVE_STATIC)

# ifdef __LIBARCHIVE_BUILD

#  ifdef __GNUC__

#   define __LA_DECL        __attribute__((dllexport)) extern

#  else

#   define __LA_DECL        __declspec(dllexport)

#  endif

# else

#  ifdef __GNUC__

#   define __LA_DECL        __attribute__((dllimport)) extern

#  else

#   define __LA_DECL        __declspec(dllimport)

#  endif

# endif

#else

/* Static libraries on all platforms and shared libraries on non-Windows. */

# define __LA_DECL

#endif

#ifdef __cplusplus

extern "C" {

#endif

/*

 * Description of an archive entry.

 *

 * You can think of this as "struct stat" with some text fields added in.

 *

 * TODO: Add "comment", "charset", and possibly other entries that are

 * supported by "pax interchange" format.  However, GNU, ustar, cpio,

 * and other variants don't support these features, so they're not an

 * excruciatingly high priority right now.

 *

 * TODO: "pax interchange" format allows essentially arbitrary

 * key/value attributes to be attached to any entry.  Supporting

 * such extensions may make this library useful for special

 * applications (e.g., a package manager could attach special

 * package-management attributes to each entry).

 */

struct archive_entry;

/*

 * File-type constants.  These are returned from archive_entry_filetype()

 * and passed to archive_entry_set_filetype().

 *

 * These values match S_XXX defines on every platform I've checked,

 * including Windows, AIX, Linux, Solaris, and BSD.  They're

 * (re)defined here because platforms generally don't define the ones

 * they don't support.  For example, Windows doesn't define S_IFLNK or

 * S_IFBLK.  Instead of having a mass of conditional logic and system

 * checks to define any S_XXX values that aren't supported locally,

 * I've just defined a new set of such constants so that

 * libarchive-based applications can manipulate and identify archive

 * entries properly even if the hosting platform can't store them on

 * disk.

 *

 * These values are also used directly within some portable formats,

 * such as cpio.  If you find a platform that varies from these, the

 * correct solution is to leave these alone and translate from these

 * portable values to platform-native values when entries are read from

 * or written to disk.

 */

#define        AE_IFMT                0170000

#define        AE_IFREG        0100000

#define        AE_IFLNK        0120000

#define        AE_IFSOCK        0140000

#define        AE_IFCHR        0020000

#define        AE_IFBLK        0060000

#define        AE_IFDIR        0040000

#define        AE_IFIFO        0010000

/*

 * Basic object manipulation

 */

__LA_DECL struct archive_entry        *archive_entry_clear(struct archive_entry *);

/* The 'clone' function does a deep copy; all of the strings are copied too. */

__LA_DECL struct archive_entry        *archive_entry_clone(struct archive_entry *);

__LA_DECL void                         archive_entry_free(struct archive_entry *);

__LA_DECL struct archive_entry        *archive_entry_new(void);

/*

 * Retrieve fields from an archive_entry.

 *

 * There are a number of implicit conversions among these fields.  For

 * example, if a regular string field is set and you read the _w wide

 * character field, the entry will implicitly convert narrow-to-wide

 * using the current locale.  Similarly, dev values are automatically

 * updated when you write devmajor or devminor and vice versa.

 *

 * In addition, fields can be "set" or "unset."  Unset string fields

 * return NULL, non-string fields have _is_set() functions to test

 * whether they've been set.  You can "unset" a string field by

 * assigning NULL; non-string fields have _unset() functions to

 * unset them.

 *

 * Note: There is one ambiguity in the above; string fields will

 * also return NULL when implicit character set conversions fail.

 * This is usually what you want.

 */

__LA_DECL time_t         archive_entry_atime(struct archive_entry *);

__LA_DECL long                 archive_entry_atime_nsec(struct archive_entry *);

__LA_DECL int                 archive_entry_atime_is_set(struct archive_entry *);

__LA_DECL time_t         archive_entry_birthtime(struct archive_entry *);

__LA_DECL long                 archive_entry_birthtime_nsec(struct archive_entry *);

__LA_DECL int                 archive_entry_birthtime_is_set(struct archive_entry *);

__LA_DECL time_t         archive_entry_ctime(struct archive_entry *);

__LA_DECL long                 archive_entry_ctime_nsec(struct archive_entry *);

__LA_DECL int                 archive_entry_ctime_is_set(struct archive_entry *);

__LA_DECL dev_t                 archive_entry_dev(struct archive_entry *);

__LA_DECL dev_t                 archive_entry_devmajor(struct archive_entry *);

__LA_DECL dev_t                 archive_entry_devminor(struct archive_entry *);

__LA_DECL __LA_MODE_T         archive_entry_filetype(struct archive_entry *);

__LA_DECL void                 archive_entry_fflags(struct archive_entry *,

                            unsigned long * /* set */,

                            unsigned long * /* clear */);

__LA_DECL const char        *archive_entry_fflags_text(struct archive_entry *);

__LA_DECL __LA_GID_T         archive_entry_gid(struct archive_entry *);

__LA_DECL const char        *archive_entry_gname(struct archive_entry *);

__LA_DECL const wchar_t        *archive_entry_gname_w(struct archive_entry *);

__LA_DECL const char        *archive_entry_hardlink(struct archive_entry *);

__LA_DECL const wchar_t        *archive_entry_hardlink_w(struct archive_entry *);

__LA_DECL __LA_INO_T         archive_entry_ino(struct archive_entry *);

__LA_DECL __LA_INT64_T         archive_entry_ino64(struct archive_entry *);

__LA_DECL __LA_MODE_T         archive_entry_mode(struct archive_entry *);

__LA_DECL time_t         archive_entry_mtime(struct archive_entry *);

__LA_DECL long                 archive_entry_mtime_nsec(struct archive_entry *);

__LA_DECL int                 archive_entry_mtime_is_set(struct archive_entry *);

__LA_DECL unsigned int         archive_entry_nlink(struct archive_entry *);

__LA_DECL const char        *archive_entry_pathname(struct archive_entry *);

__LA_DECL const wchar_t        *archive_entry_pathname_w(struct archive_entry *);

__LA_DECL dev_t                 archive_entry_rdev(struct archive_entry *);

__LA_DECL dev_t                 archive_entry_rdevmajor(struct archive_entry *);

__LA_DECL dev_t                 archive_entry_rdevminor(struct archive_entry *);

__LA_DECL const char        *archive_entry_sourcepath(struct archive_entry *);

__LA_DECL __LA_INT64_T         archive_entry_size(struct archive_entry *);

__LA_DECL int                 archive_entry_size_is_set(struct archive_entry *);

__LA_DECL const char        *archive_entry_strmode(struct archive_entry *);

__LA_DECL const char        *archive_entry_symlink(struct archive_entry *);

__LA_DECL const wchar_t        *archive_entry_symlink_w(struct archive_entry *);

__LA_DECL __LA_UID_T         archive_entry_uid(struct archive_entry *);

__LA_DECL const char        *archive_entry_uname(struct archive_entry *);

__LA_DECL const wchar_t        *archive_entry_uname_w(struct archive_entry *);

/*

 * Set fields in an archive_entry.

 *

 * Note that string 'set' functions do not copy the string, only the pointer.

 * In contrast, 'copy' functions do copy the object pointed to.

 *

 * Note: As of libarchive 2.4, 'set' functions do copy the string and

 * are therefore exact synonyms for the 'copy' versions.  The 'copy'

 * names will be retired in libarchive 3.0.

 */

__LA_DECL void        archive_entry_set_atime(struct archive_entry *, time_t, long);

__LA_DECL void  archive_entry_unset_atime(struct archive_entry *);

#if defined(_WIN32) && !defined(__CYGWIN__)

__LA_DECL void archive_entry_copy_bhfi(struct archive_entry *,

                                                                           BY_HANDLE_FILE_INFORMATION *);

#endif

__LA_DECL void        archive_entry_set_birthtime(struct archive_entry *, time_t, long);

__LA_DECL void  archive_entry_unset_birthtime(struct archive_entry *);

__LA_DECL void        archive_entry_set_ctime(struct archive_entry *, time_t, long);

__LA_DECL void  archive_entry_unset_ctime(struct archive_entry *);

__LA_DECL void        archive_entry_set_dev(struct archive_entry *, dev_t);

__LA_DECL void        archive_entry_set_devmajor(struct archive_entry *, dev_t);

__LA_DECL void        archive_entry_set_devminor(struct archive_entry *, dev_t);

__LA_DECL void        archive_entry_set_filetype(struct archive_entry *, unsigned int);

__LA_DECL void        archive_entry_set_fflags(struct archive_entry *,

            unsigned long /* set */, unsigned long /* clear */);

/* Returns pointer to start of first invalid token, or NULL if none. */

/* Note that all recognized tokens are processed, regardless. */

__LA_DECL const char *archive_entry_copy_fflags_text(struct archive_entry *,

            const char *);

__LA_DECL const wchar_t *archive_entry_copy_fflags_text_w(struct archive_entry *,

            const wchar_t *);

__LA_DECL void        archive_entry_set_gid(struct archive_entry *, __LA_GID_T);

__LA_DECL void        archive_entry_set_gname(struct archive_entry *, const char *);

__LA_DECL void        archive_entry_copy_gname(struct archive_entry *, const char *);

__LA_DECL void        archive_entry_copy_gname_w(struct archive_entry *, const wchar_t *);

__LA_DECL int        archive_entry_update_gname_utf8(struct archive_entry *, const char *);

__LA_DECL void        archive_entry_set_hardlink(struct archive_entry *, const char *);

__LA_DECL void        archive_entry_copy_hardlink(struct archive_entry *, const char *);

__LA_DECL void        archive_entry_copy_hardlink_w(struct archive_entry *, const wchar_t *);

__LA_DECL int        archive_entry_update_hardlink_utf8(struct archive_entry *, const char *);

#if ARCHIVE_VERSION_NUMBER >= 3000000

/* Starting with libarchive 3.0, this will be synonym for ino64. */

__LA_DECL void        archive_entry_set_ino(struct archive_entry *, __LA_INT64_T);

#else

__LA_DECL void        archive_entry_set_ino(struct archive_entry *, unsigned long);

#endif

__LA_DECL void        archive_entry_set_ino64(struct archive_entry *, __LA_INT64_T);

__LA_DECL void        archive_entry_set_link(struct archive_entry *, const char *);

__LA_DECL void        archive_entry_copy_link(struct archive_entry *, const char *);

__LA_DECL void        archive_entry_copy_link_w(struct archive_entry *, const wchar_t *);

__LA_DECL int        archive_entry_update_link_utf8(struct archive_entry *, const char *);

__LA_DECL void        archive_entry_set_mode(struct archive_entry *, __LA_MODE_T);

__LA_DECL void        archive_entry_set_mtime(struct archive_entry *, time_t, long);

__LA_DECL void  archive_entry_unset_mtime(struct archive_entry *);

__LA_DECL void        archive_entry_set_nlink(struct archive_entry *, unsigned int);

__LA_DECL void        archive_entry_set_pathname(struct archive_entry *, const char *);

__LA_DECL void        archive_entry_copy_pathname(struct archive_entry *, const char *);

__LA_DECL void        archive_entry_copy_pathname_w(struct archive_entry *, const wchar_t *);

__LA_DECL int        archive_entry_update_pathname_utf8(struct archive_entry *, const char *);

__LA_DECL void        archive_entry_set_perm(struct archive_entry *, __LA_MODE_T);

__LA_DECL void        archive_entry_set_rdev(struct archive_entry *, dev_t);

__LA_DECL void        archive_entry_set_rdevmajor(struct archive_entry *, dev_t);

__LA_DECL void        archive_entry_set_rdevminor(struct archive_entry *, dev_t);

__LA_DECL void        archive_entry_set_size(struct archive_entry *, __LA_INT64_T);

__LA_DECL void        archive_entry_unset_size(struct archive_entry *);

__LA_DECL void        archive_entry_copy_sourcepath(struct archive_entry *, const char *);

__LA_DECL void        archive_entry_set_symlink(struct archive_entry *, const char *);

__LA_DECL void        archive_entry_copy_symlink(struct archive_entry *, const char *);

__LA_DECL void        archive_entry_copy_symlink_w(struct archive_entry *, const wchar_t *);

__LA_DECL int        archive_entry_update_symlink_utf8(struct archive_entry *, const char *);

__LA_DECL void        archive_entry_set_uid(struct archive_entry *, __LA_UID_T);

__LA_DECL void        archive_entry_set_uname(struct archive_entry *, const char *);

__LA_DECL void        archive_entry_copy_uname(struct archive_entry *, const char *);

__LA_DECL void        archive_entry_copy_uname_w(struct archive_entry *, const wchar_t *);

__LA_DECL int        archive_entry_update_uname_utf8(struct archive_entry *, const char *);

/*

 * Routines to bulk copy fields to/from a platform-native "struct

 * stat."  Libarchive used to just store a struct stat inside of each

 * archive_entry object, but this created issues when trying to

 * manipulate archives on systems different than the ones they were

 * created on.

 *

 * TODO: On Linux, provide both stat32 and stat64 versions of these functions.

 */

__LA_DECL const struct stat        *archive_entry_stat(struct archive_entry *);

__LA_DECL void        archive_entry_copy_stat(struct archive_entry *, const struct stat *);

/*

 * ACL routines.  This used to simply store and return text-format ACL

 * strings, but that proved insufficient for a number of reasons:

 *   = clients need control over uname/uid and gname/gid mappings

 *   = there are many different ACL text formats

 *   = would like to be able to read/convert archives containing ACLs

 *     on platforms that lack ACL libraries

 *

 *  This last point, in particular, forces me to implement a reasonably

 *  complete set of ACL support routines.

 *

 *  TODO: Extend this to support NFSv4/NTFS permissions.  That should

 *  allow full ACL support on Mac OS, in particular, which uses

 *  POSIX.1e-style interfaces to manipulate NFSv4/NTFS permissions.

 */

/*

 * Permission bits mimic POSIX.1e.  Note that I've not followed POSIX.1e's

 * "permset"/"perm" abstract type nonsense.  A permset is just a simple

 * bitmap, following long-standing Unix tradition.

 */

#define        ARCHIVE_ENTRY_ACL_EXECUTE        1

#define        ARCHIVE_ENTRY_ACL_WRITE                2

#define        ARCHIVE_ENTRY_ACL_READ                4

/* We need to be able to specify either or both of these. */

#define        ARCHIVE_ENTRY_ACL_TYPE_ACCESS        256

#define        ARCHIVE_ENTRY_ACL_TYPE_DEFAULT        512

/* Tag values mimic POSIX.1e */

#define        ARCHIVE_ENTRY_ACL_USER                10001        /* Specified user. */

#define        ARCHIVE_ENTRY_ACL_USER_OBJ         10002        /* User who owns the file. */

#define        ARCHIVE_ENTRY_ACL_GROUP                10003        /* Specified group. */

#define        ARCHIVE_ENTRY_ACL_GROUP_OBJ        10004        /* Group who owns the file. */

#define        ARCHIVE_ENTRY_ACL_MASK                10005        /* Modify group access. */

#define        ARCHIVE_ENTRY_ACL_OTHER                10006        /* Public. */

/*

 * Set the ACL by clearing it and adding entries one at a time.

 * Unlike the POSIX.1e ACL routines, you must specify the type

 * (access/default) for each entry.  Internally, the ACL data is just

 * a soup of entries.  API calls here allow you to retrieve just the

 * entries of interest.  This design (which goes against the spirit of

 * POSIX.1e) is useful for handling archive formats that combine

 * default and access information in a single ACL list.

 */

__LA_DECL void         archive_entry_acl_clear(struct archive_entry *);

__LA_DECL void         archive_entry_acl_add_entry(struct archive_entry *,

            int /* type */, int /* permset */, int /* tag */,

            int /* qual */, const char * /* name */);

__LA_DECL void         archive_entry_acl_add_entry_w(struct archive_entry *,

            int /* type */, int /* permset */, int /* tag */,

            int /* qual */, const wchar_t * /* name */);

/*

 * To retrieve the ACL, first "reset", then repeatedly ask for the

 * "next" entry.  The want_type parameter allows you to request only

 * access entries or only default entries.

 */

__LA_DECL int         archive_entry_acl_reset(struct archive_entry *, int /* want_type */);

__LA_DECL int         archive_entry_acl_next(struct archive_entry *, int /* want_type */,

            int * /* type */, int * /* permset */, int * /* tag */,

            int * /* qual */, const char ** /* name */);

__LA_DECL int         archive_entry_acl_next_w(struct archive_entry *, int /* want_type */,

            int * /* type */, int * /* permset */, int * /* tag */,

            int * /* qual */, const wchar_t ** /* name */);

/*

 * Construct a text-format ACL.  The flags argument is a bitmask that

 * can include any of the following:

 *

 * ARCHIVE_ENTRY_ACL_TYPE_ACCESS - Include access entries.

 * ARCHIVE_ENTRY_ACL_TYPE_DEFAULT - Include default entries.

 * ARCHIVE_ENTRY_ACL_STYLE_EXTRA_ID - Include extra numeric ID field in

 *    each ACL entry.  (As used by 'star'.)

 * ARCHIVE_ENTRY_ACL_STYLE_MARK_DEFAULT - Include "default:" before each

 *    default ACL entry.

 */

#define        ARCHIVE_ENTRY_ACL_STYLE_EXTRA_ID        1024

#define        ARCHIVE_ENTRY_ACL_STYLE_MARK_DEFAULT        2048

__LA_DECL const wchar_t        *archive_entry_acl_text_w(struct archive_entry *,

                    int /* flags */);

/* Return a count of entries matching 'want_type' */

__LA_DECL int         archive_entry_acl_count(struct archive_entry *, int /* want_type */);

/*

 * Private ACL parser.  This is private because it handles some

 * very weird formats that clients should not be messing with.

 * Clients should only deal with their platform-native formats.

 * Because of the need to support many formats cleanly, new arguments

 * are likely to get added on a regular basis.  Clients who try to use

 * this interface are likely to be surprised when it changes.

 *

 * You were warned!

 *

 * TODO: Move this declaration out of the public header and into

 * a private header.  Warnings above are silly.

 */

__LA_DECL int                 __archive_entry_acl_parse_w(struct archive_entry *,

                    const wchar_t *, int /* type */);

/*

 * extended attributes

 */

__LA_DECL void         archive_entry_xattr_clear(struct archive_entry *);

__LA_DECL void         archive_entry_xattr_add_entry(struct archive_entry *,

            const char * /* name */, const void * /* value */,

            size_t /* size */);

/*

 * To retrieve the xattr list, first "reset", then repeatedly ask for the

 * "next" entry.

 */

__LA_DECL int        archive_entry_xattr_count(struct archive_entry *);

__LA_DECL int        archive_entry_xattr_reset(struct archive_entry *);

__LA_DECL int        archive_entry_xattr_next(struct archive_entry *,

            const char ** /* name */, const void ** /* value */, size_t *);

/*

 * Utility to match up hardlinks.

 *

 * The 'struct archive_entry_linkresolver' is a cache of archive entries

 * for files with multiple links.  Here's how to use it:

 *   1. Create a lookup object with archive_entry_linkresolver_new()

 *   2. Tell it the archive format you're using.

 *   3. Hand each archive_entry to archive_entry_linkify().

 *      That function will return 0, 1, or 2 entries that should

 *      be written.

 *   4. Call archive_entry_linkify(resolver, NULL) until

 *      no more entries are returned.

 *   5. Call archive_entry_link_resolver_free(resolver) to free resources.

 *

 * The entries returned have their hardlink and size fields updated

 * appropriately.  If an entry is passed in that does not refer to

 * a file with multiple links, it is returned unchanged.  The intention

 * is that you should be able to simply filter all entries through

 * this machine.

 *

 * To make things more efficient, be sure that each entry has a valid

 * nlinks value.  The hardlink cache uses this to track when all links

 * have been found.  If the nlinks value is zero, it will keep every

 * name in the cache indefinitely, which can use a lot of memory.

 *

 * Note that archive_entry_size() is reset to zero if the file

 * body should not be written to the archive.  Pay attention!

 */

struct archive_entry_linkresolver;

/*

 * There are three different strategies for marking hardlinks.

 * The descriptions below name them after the best-known

 * formats that rely on each strategy:

 *

 * "Old cpio" is the simplest, it always returns any entry unmodified.

 *    As far as I know, only cpio formats use this.  Old cpio archives

 *    store every link with the full body; the onus is on the dearchiver

 *    to detect and properly link the files as they are restored.

 * "tar" is also pretty simple; it caches a copy the first time it sees

 *    any link.  Subsequent appearances are modified to be hardlink

 *    references to the first one without any body.  Used by all tar

 *    formats, although the newest tar formats permit the "old cpio" strategy

 *    as well.  This strategy is very simple for the dearchiver,

 *    and reasonably straightforward for the archiver.

 * "new cpio" is trickier.  It stores the body only with the last

 *    occurrence.  The complication is that we might not

 *    see every link to a particular file in a single session, so

 *    there's no easy way to know when we've seen the last occurrence.

 *    The solution here is to queue one link until we see the next.

 *    At the end of the session, you can enumerate any remaining

 *    entries by calling archive_entry_linkify(NULL) and store those

 *    bodies.  If you have a file with three links l1, l2, and l3,

 *    you'll get the following behavior if you see all three links:

 *           linkify(l1) => NULL   (the resolver stores l1 internally)

 *           linkify(l2) => l1     (resolver stores l2, you write l1)

 *           linkify(l3) => l2, l3 (all links seen, you can write both).

 *    If you only see l1 and l2, you'll get this behavior:

 *           linkify(l1) => NULL

 *           linkify(l2) => l1

 *           linkify(NULL) => l2   (at end, you retrieve remaining links)

 *    As the name suggests, this strategy is used by newer cpio variants.

 *    It's noticably more complex for the archiver, slightly more complex

 *    for the dearchiver than the tar strategy, but makes it straightforward

 *    to restore a file using any link by simply continuing to scan until

 *    you see a link that is stored with a body.  In contrast, the tar

 *    strategy requires you to rescan the archive from the beginning to

 *    correctly extract an arbitrary link.

 */

__LA_DECL struct archive_entry_linkresolver *archive_entry_linkresolver_new(void);

__LA_DECL void archive_entry_linkresolver_set_strategy(

        struct archive_entry_linkresolver *, int /* format_code */);

__LA_DECL void archive_entry_linkresolver_free(struct archive_entry_linkresolver *);

__LA_DECL void archive_entry_linkify(struct archive_entry_linkresolver *,

    struct archive_entry **, struct archive_entry **);

#ifdef __cplusplus

}

#endif

/* This is meaningless outside of this header. */

#undef __LA_DECL

#endif /* !ARCHIVE_ENTRY_H_INCLUDED */