contrib/libarchive-2.1/tar/tree.h

   1 /*-
   2  * Copyright (c) 2003-2007 Tim Kientzle
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
  15  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  16  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  17  * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
  18  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  19  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  20  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  21  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  23  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  24  *
  25  * $FreeBSD: src/usr.bin/tar/tree.h,v 1.3 2007/01/09 08:12:17 kientzle Exp $
  26  */
  27
  28 /*-
  29  * A set of routines for traversing directory trees.
  30  * Similar in concept to the fts library, but with a few
  31  * important differences:
  32  *    * Uses less memory.  In particular, fts stores an entire directory
  33  *      in memory at a time.  This package only keeps enough subdirectory
  34  *      information in memory to track the traversal.  Information
  35  *      about non-directories is discarded as soon as possible.
  36  *    * Supports very deep logical traversals.  The fts package
  37  *      uses "non-chdir" approach for logical traversals.  This
  38  *      package does use a chdir approach for logical traversals
  39  *      and can therefore handle pathnames much longer than
  40  *      PATH_MAX.
  41  *    * Supports deep physical traversals "out of the box."
  42  *      Due to the memory optimizations above, there's no need to
  43  *      limit dir names to 32k.
  44  */
  45
  46 #include <sys/stat.h>
  47 #include <stdio.h>
  48
  49 struct tree;
  50
  51 /* Initiate/terminate a tree traversal. */
  52 struct tree *tree_open(const char * /* pathname */);
  53 void tree_close(struct tree *);
  54
  55 /*
  56  * tree_next() returns Zero if there is no next entry, non-zero if there is.
  57  * Note that directories are potentially visited three times.  The first
  58  * time as "regular" file.  If tree_descend() is invoked at that time,
  59  * the directory is added to a work list and will be visited two more
  60  * times:  once just after descending into the directory and again
  61  * just after ascending back to the parent.
  62  *
  63  * TREE_ERROR is returned if the descent failed (because the
  64  * directory couldn't be opened, for instance).  This is returned
  65  * instead of TREE_PREVISIT/TREE_POSTVISIT.
  66  */
  67 #define TREE_REGULAR    1
  68 #define TREE_POSTDESCENT        2
  69 #define TREE_POSTASCENT 3
  70 #define TREE_ERROR_DIR  -1
  71 int tree_next(struct tree *);
  72
  73 int tree_errno(struct tree *);
  74
  75 /*
  76  * Request that current entry be visited.  If you invoke it on every
  77  * directory, you'll get a physical traversal.  This is ignored if the
  78  * current entry isn't a directory or a link to a directory.  So, if
  79  * you invoke this on every returned path, you'll get a full logical
  80  * traversal.
  81  */
  82 void tree_descend(struct tree *);
  83
  84 /*
  85  * Return information about the current entry.
  86  */
  87
  88 int tree_current_depth(struct tree *);
  89 /*
  90  * The current full pathname, length of the full pathname,
  91  * and a name that can be used to access the file.
  92  * Because tree does use chdir extensively, the access path is
  93  * almost never the same as the full current path.
  94  */
  95 const char *tree_current_path(struct tree *);
  96 size_t tree_current_pathlen(struct tree *);
  97 const char *tree_current_access_path(struct tree *);
  98 /*
  99  * Request the lstat() or stat() data for the current path.  Since the
 100  * tree package needs to do some of this anyway, and caches the
 101  * results, you should take advantage of it here if you need it rather
 102  * than make a redundant stat() or lstat() call of your own.
 103  */
 104 const struct stat *tree_current_stat(struct tree *);
 105 const struct stat *tree_current_lstat(struct tree *);
 106 /* The following tests may use mechanisms much faster than stat()/lstat(). */
 107 /* "is_physical_dir" is equivalent to S_ISDIR(tree_current_lstat()->st_mode) */
 108 int tree_current_is_physical_dir(struct tree *);
 109 /* "is_physical_link" is equivalent to S_ISLNK(tree_current_lstat()->st_mode) */
 110 int tree_current_is_physical_link(struct tree *);
 111 /* "is_dir" is equivalent to S_ISDIR(tree_current_stat()->st_mode) */
 112 int tree_current_is_dir(struct tree *);
 113
 114 /* For testing/debugging: Dump the internal status to the given filehandle. */
 115 void tree_dump(struct tree *, FILE *);