| /*- |
| * 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: src/lib/libarchive/archive_entry.h,v 1.31 2008/12/06 06:18:46 kientzle Exp $ |
| */ |
| |
| #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> |
| |
| /* 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 |
| #define __LA_UID_T unsigned int |
| #define __LA_GID_T unsigned int |
| #define __LA_DEV_T unsigned int |
| #define __LA_MODE_T unsigned short |
| #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_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 *); |
| __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 void archive_entry_set_ino(struct archive_entry *, unsigned long); |
| __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 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 */ |
