1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
|
/*-
* 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.
*
* $FreeBSD$
*/
/*-
* 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 potentially visited three
* times. Directories are always visited first as part of enumerating
* their parent. 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 and
* again just after ascending back to the parent.
*
* TREE_ERROR_DIR is returned if the descent failed (because the
* directory couldn't be opened, for instance). This is returned
* instead of TREE_PREVISIT/TREE_POSTVISIT. 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.
*/
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 *);
|
