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Diffstat (limited to 'Utilities/cmlibarchive/tar/tree.h')
-rw-r--r-- | Utilities/cmlibarchive/tar/tree.h | 141 |
1 files changed, 141 insertions, 0 deletions
diff --git a/Utilities/cmlibarchive/tar/tree.h b/Utilities/cmlibarchive/tar/tree.h new file mode 100644 index 0000000..a99edf2 --- /dev/null +++ b/Utilities/cmlibarchive/tar/tree.h @@ -0,0 +1,141 @@ +/*- + * Copyright (c) 2003-2007 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/usr.bin/tar/tree.h,v 1.4 2008/11/27 05:49:52 kientzle Exp $ + */ + +/*- + * A set of routines for traversing directory trees. + * Similar in concept to the fts library, but with a few + * important differences: + * * Uses less memory. In particular, fts stores an entire directory + * in memory at a time. This package only keeps enough subdirectory + * information in memory to track the traversal. Information + * about non-directories is discarded as soon as possible. + * * Supports very deep logical traversals. The fts package + * uses "non-chdir" approach for logical traversals. This + * package does use a chdir approach for logical traversals + * and can therefore handle pathnames much longer than PATH_MAX. + * * Supports deep physical traversals "out of the box." + * Due to the memory optimizations above, there's no need to + * limit dir names to 32k. + */ + +#include <sys/stat.h> +#include <stdio.h> + +struct tree; + +/* Initiate/terminate a tree traversal. */ +struct tree *tree_open(const char * /* pathname */); +void tree_close(struct tree *); + +/* + * tree_next() returns Zero if there is no next entry, non-zero if + * there is. Note that directories are visited three times. + * Directories are always visited first as part of enumerating their + * parent; that is a "regular" visit. If tree_descend() is invoked at + * that time, the directory is added to a work list and will + * subsequently be visited two more times: once just after descending + * into the directory ("postdescent") and again just after ascending + * back to the parent ("postascent"). + * + * TREE_ERROR_DIR is returned if the descent failed (because the + * directory couldn't be opened, for instance). This is returned + * instead of TREE_POSTDESCENT/TREE_POSTASCENT. TREE_ERROR_DIR is not a + * fatal error, but it does imply that the relevant subtree won't be + * visited. TREE_ERROR_FATAL is returned for an error that left the + * traversal completely hosed. Right now, this is only returned for + * chdir() failures during ascent. + */ +#define TREE_REGULAR 1 +#define TREE_POSTDESCENT 2 +#define TREE_POSTASCENT 3 +#define TREE_ERROR_DIR -1 +#define TREE_ERROR_FATAL -2 + +int tree_next(struct tree *); + +/* Errno value associated with the last traversal error. */ +int tree_errno(struct tree *); + +/* + * Request that current entry be visited. If you invoke it on every + * directory, you'll get a physical traversal. This is ignored if the + * current entry isn't a directory or a link to a directory. So, if + * you invoke this on every returned path, you'll get a full logical + * traversal. + */ +void tree_descend(struct tree *); + +/* + * Return information about the current entry. + */ + +/* Current depth in the traversal. */ +int tree_current_depth(struct tree *); + +/* + * The current full pathname, length of the full pathname, and a name + * that can be used to access the file. Because tree does use chdir + * extensively, the access path is almost never the same as the full + * current path. + * + * TODO: Flesh out this interface to provide other information. In + * particular, Windows can provide file size, mode, and some permission + * information without invoking stat() at all. + * + * TODO: On platforms that support it, use openat()-style operations + * to eliminate the chdir() operations entirely while still supporting + * arbitrarily deep traversals. This makes access_path troublesome to + * support, of course, which means we'll need a rich enough interface + * that clients can function without it. (In particular, we'll need + * tree_current_open() that returns an open file descriptor.) + * + * TODO: Provide tree_current_archive_entry(). + */ +const char *tree_current_path(struct tree *); +size_t tree_current_pathlen(struct tree *); +const char *tree_current_access_path(struct tree *); + +/* + * Request the lstat() or stat() data for the current path. Since the + * tree package needs to do some of this anyway, and caches the + * results, you should take advantage of it here if you need it rather + * than make a redundant stat() or lstat() call of your own. + */ +const struct stat *tree_current_stat(struct tree *); +const struct stat *tree_current_lstat(struct tree *); + +/* The following functions use tricks to avoid a certain number of + * stat()/lstat() calls. */ +/* "is_physical_dir" is equivalent to S_ISDIR(tree_current_lstat()->st_mode) */ +int tree_current_is_physical_dir(struct tree *); +/* "is_physical_link" is equivalent to S_ISLNK(tree_current_lstat()->st_mode) */ +int tree_current_is_physical_link(struct tree *); +/* "is_dir" is equivalent to S_ISDIR(tree_current_stat()->st_mode) */ +int tree_current_is_dir(struct tree *); + +/* For testing/debugging: Dump the internal status to the given filehandle. */ +void tree_dump(struct tree *, FILE *); |