Mercurial > hg > octave-lojdl > gnulib-hg
annotate lib/fts_.h @ 6035:a166800910b5
Mention that with FTS_LOGICAL, we use FTS_TIGHT_CYCLE_CHECK.
| author | Jim Meyering <jim@meyering.net> |
|---|---|
| date | Sun, 14 Aug 2005 14:45:33 +0000 |
| parents | c47674a83a78 |
| children | 43e3888c56c4 |
| rev | line source |
|---|---|
| 5858 | 1 /* Traverse a file hierarchy. |
| 2 | |
| 3 Copyright (C) 2004, 2005 Free Software Foundation, Inc. | |
| 4 | |
| 5 This program is free software; you can redistribute it and/or modify | |
| 6 it under the terms of the GNU General Public License as published by | |
| 7 the Free Software Foundation; either version 2, or (at your option) | |
| 8 any later version. | |
| 9 | |
| 10 This program is distributed in the hope that it will be useful, | |
| 11 but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
| 13 GNU General Public License for more details. | |
| 14 | |
| 15 You should have received a copy of the GNU General Public License | |
| 16 along with this program; if not, write to the Free Software Foundation, | |
| 17 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ | |
| 18 | |
| 19 /* | |
| 20 * Copyright (c) 1989, 1993 | |
| 21 * The Regents of the University of California. All rights reserved. | |
| 22 * | |
| 23 * Redistribution and use in source and binary forms, with or without | |
| 24 * modification, are permitted provided that the following conditions | |
| 25 * are met: | |
| 26 * 1. Redistributions of source code must retain the above copyright | |
| 27 * notice, this list of conditions and the following disclaimer. | |
| 28 * 2. Redistributions in binary form must reproduce the above copyright | |
| 29 * notice, this list of conditions and the following disclaimer in the | |
| 30 * documentation and/or other materials provided with the distribution. | |
| 31 * 4. Neither the name of the University nor the names of its contributors | |
| 32 * may be used to endorse or promote products derived from this software | |
| 33 * without specific prior written permission. | |
| 34 * | |
| 35 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND | |
| 36 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
| 37 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | |
| 38 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE | |
| 39 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL | |
| 40 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS | |
| 41 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | |
| 42 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT | |
| 43 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY | |
| 44 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF | |
| 45 * SUCH DAMAGE. | |
| 46 * | |
| 47 * @(#)fts.h 8.3 (Berkeley) 8/14/94 | |
| 48 */ | |
| 49 | |
| 50 #ifndef _FTS_H | |
| 51 # define _FTS_H 1 | |
| 52 | |
| 53 # ifdef _LIBC | |
| 54 # include <features.h> | |
| 5872 | 55 # define _LGPL_PACKAGE 1 |
| 5858 | 56 # else |
| 57 # undef __THROW | |
| 58 # define __THROW | |
| 59 # undef __BEGIN_DECLS | |
| 60 # define __BEGIN_DECLS | |
| 61 # undef __END_DECLS | |
| 62 # define __END_DECLS | |
| 63 # endif | |
| 64 | |
| 65 # include <stddef.h> | |
| 66 # include <sys/types.h> | |
|
5867
67b499052f7f
* fts.c: Include fts_.h first, to check interface.
Paul Eggert <eggert@cs.ucla.edu>
parents:
5858
diff
changeset
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67 # include <sys/stat.h> |
| 5858 | 68 |
| 69 typedef struct { | |
| 70 struct _ftsent *fts_cur; /* current node */ | |
| 71 struct _ftsent *fts_child; /* linked list of children */ | |
| 72 struct _ftsent **fts_array; /* sort array */ | |
| 73 dev_t fts_dev; /* starting device # */ | |
| 5907 | 74 char *fts_path; /* file name for this descent */ |
| 5858 | 75 int fts_rfd; /* fd for root */ |
| 76 size_t fts_pathlen; /* sizeof(path) */ | |
| 77 size_t fts_nitems; /* elements in the sort array */ | |
| 78 int (*fts_compar) (struct _ftsent const **, struct _ftsent const **); | |
| 79 /* compare fn */ | |
| 80 | |
| 81 # define FTS_COMFOLLOW 0x0001 /* follow command line symlinks */ | |
| 82 # define FTS_LOGICAL 0x0002 /* logical walk */ | |
| 83 # define FTS_NOCHDIR 0x0004 /* don't change directories */ | |
| 84 # define FTS_NOSTAT 0x0008 /* don't get stat info */ | |
| 85 # define FTS_PHYSICAL 0x0010 /* physical walk */ | |
| 86 # define FTS_SEEDOT 0x0020 /* return dot and dot-dot */ | |
| 87 # define FTS_XDEV 0x0040 /* don't cross devices */ | |
| 88 # define FTS_WHITEOUT 0x0080 /* return whiteout information */ | |
| 89 | |
| 90 /* There are two ways to detect cycles. | |
|
6035
a166800910b5
Mention that with FTS_LOGICAL, we use FTS_TIGHT_CYCLE_CHECK.
Jim Meyering <jim@meyering.net>
parents:
5907
diff
changeset
|
91 The lazy way (which works only with FTS_PHYSICAL), |
|
a166800910b5
Mention that with FTS_LOGICAL, we use FTS_TIGHT_CYCLE_CHECK.
Jim Meyering <jim@meyering.net>
parents:
5907
diff
changeset
|
92 with which one may process a directory that is a |
| 5858 | 93 part of the cycle several times before detecting the cycle. |
| 94 The `tight' way, whereby fts uses more memory (proportional | |
| 95 to number of `active' directories, aka distance from root | |
| 96 of current tree to current directory -- see active_dir_ht) | |
| 97 to detect any cycle right away. For example, du must use | |
| 98 this option to avoid counting disk space in a cycle multiple | |
| 99 times, but chown -R need not. | |
|
6035
a166800910b5
Mention that with FTS_LOGICAL, we use FTS_TIGHT_CYCLE_CHECK.
Jim Meyering <jim@meyering.net>
parents:
5907
diff
changeset
|
100 The default is to use the constant-memory lazy way, when possible |
|
a166800910b5
Mention that with FTS_LOGICAL, we use FTS_TIGHT_CYCLE_CHECK.
Jim Meyering <jim@meyering.net>
parents:
5907
diff
changeset
|
101 (see below). |
|
a166800910b5
Mention that with FTS_LOGICAL, we use FTS_TIGHT_CYCLE_CHECK.
Jim Meyering <jim@meyering.net>
parents:
5907
diff
changeset
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102 |
|
a166800910b5
Mention that with FTS_LOGICAL, we use FTS_TIGHT_CYCLE_CHECK.
Jim Meyering <jim@meyering.net>
parents:
5907
diff
changeset
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103 However, with FTS_LOGICAL (when following symlinks, e.g., chown -L) |
|
a166800910b5
Mention that with FTS_LOGICAL, we use FTS_TIGHT_CYCLE_CHECK.
Jim Meyering <jim@meyering.net>
parents:
5907
diff
changeset
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104 using lazy cycle detection is inadequate. For example, traversing |
|
a166800910b5
Mention that with FTS_LOGICAL, we use FTS_TIGHT_CYCLE_CHECK.
Jim Meyering <jim@meyering.net>
parents:
5907
diff
changeset
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105 a directory containing a symbolic link to a peer directory, it is |
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a166800910b5
Mention that with FTS_LOGICAL, we use FTS_TIGHT_CYCLE_CHECK.
Jim Meyering <jim@meyering.net>
parents:
5907
diff
changeset
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106 possible to encounter the same directory twice even though there |
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a166800910b5
Mention that with FTS_LOGICAL, we use FTS_TIGHT_CYCLE_CHECK.
Jim Meyering <jim@meyering.net>
parents:
5907
diff
changeset
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107 is no cycle: |
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a166800910b5
Mention that with FTS_LOGICAL, we use FTS_TIGHT_CYCLE_CHECK.
Jim Meyering <jim@meyering.net>
parents:
5907
diff
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108 dir |
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a166800910b5
Mention that with FTS_LOGICAL, we use FTS_TIGHT_CYCLE_CHECK.
Jim Meyering <jim@meyering.net>
parents:
5907
diff
changeset
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109 ... |
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a166800910b5
Mention that with FTS_LOGICAL, we use FTS_TIGHT_CYCLE_CHECK.
Jim Meyering <jim@meyering.net>
parents:
5907
diff
changeset
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110 slink -> dir |
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a166800910b5
Mention that with FTS_LOGICAL, we use FTS_TIGHT_CYCLE_CHECK.
Jim Meyering <jim@meyering.net>
parents:
5907
diff
changeset
|
111 So, when FTS_LOGICAL is selected, we have to use a different |
|
a166800910b5
Mention that with FTS_LOGICAL, we use FTS_TIGHT_CYCLE_CHECK.
Jim Meyering <jim@meyering.net>
parents:
5907
diff
changeset
|
112 mode of cycle detection: FTS_TIGHT_CYCLE_CHECK. */ |
| 5858 | 113 # define FTS_TIGHT_CYCLE_CHECK 0x0100 |
| 114 | |
| 115 # define FTS_OPTIONMASK 0x01ff /* valid user option mask */ | |
| 116 | |
| 117 # define FTS_NAMEONLY 0x1000 /* (private) child names only */ | |
| 118 # define FTS_STOP 0x2000 /* (private) unrecoverable error */ | |
| 119 int fts_options; /* fts_open options, global flags */ | |
| 120 | |
| 5872 | 121 # if !_LGPL_PACKAGE |
| 122 union { | |
| 123 /* This data structure is used if FTS_TIGHT_CYCLE_CHECK is | |
| 124 specified. It records the directories between a starting | |
| 125 point and the current directory. I.e., a directory is | |
| 126 recorded here IFF we have visited it once, but we have not | |
| 127 yet completed processing of all its entries. Every time we | |
| 128 visit a new directory, we add that directory to this set. | |
| 129 When we finish with a directory (usually by visiting it a | |
| 130 second time), we remove it from this set. Each entry in | |
| 131 this data structure is a device/inode pair. This data | |
| 132 structure is used to detect directory cycles efficiently and | |
| 133 promptly even when the depth of a hierarchy is in the tens | |
| 134 of thousands. */ | |
| 135 struct hash_table *ht; | |
| 136 | |
| 137 /* This data structure uses lazy checking, as done by rm via | |
| 138 cycle-check.c. It's the default, but it's not appropriate | |
| 139 for programs like du. */ | |
| 140 struct cycle_check_state *state; | |
| 141 } fts_cycle; | |
| 142 # endif | |
| 5858 | 143 } FTS; |
| 144 | |
| 145 typedef struct _ftsent { | |
| 146 struct _ftsent *fts_cycle; /* cycle node */ | |
| 147 struct _ftsent *fts_parent; /* parent directory */ | |
| 148 struct _ftsent *fts_link; /* next file in directory */ | |
| 149 long fts_number; /* local numeric value */ | |
| 150 void *fts_pointer; /* local address value */ | |
| 5907 | 151 char *fts_accpath; /* access file name */ |
| 152 char *fts_path; /* root name; == fts_fts->fts_path */ | |
| 5858 | 153 int fts_errno; /* errno for this node */ |
| 154 int fts_symfd; /* fd for symlink */ | |
| 155 size_t fts_pathlen; /* strlen(fts_path) */ | |
| 156 | |
| 157 FTS *fts_fts; /* the file hierarchy itself */ | |
| 158 | |
| 159 # define FTS_ROOTPARENTLEVEL (-1) | |
| 160 # define FTS_ROOTLEVEL 0 | |
| 161 ptrdiff_t fts_level; /* depth (-1 to N) */ | |
| 162 | |
| 163 size_t fts_namelen; /* strlen(fts_name) */ | |
| 164 | |
| 165 # define FTS_D 1 /* preorder directory */ | |
| 166 # define FTS_DC 2 /* directory that causes cycles */ | |
| 167 # define FTS_DEFAULT 3 /* none of the above */ | |
| 168 # define FTS_DNR 4 /* unreadable directory */ | |
| 169 # define FTS_DOT 5 /* dot or dot-dot */ | |
| 170 # define FTS_DP 6 /* postorder directory */ | |
| 171 # define FTS_ERR 7 /* error; errno is set */ | |
| 172 # define FTS_F 8 /* regular file */ | |
| 173 # define FTS_INIT 9 /* initialized only */ | |
| 174 # define FTS_NS 10 /* stat(2) failed */ | |
| 175 # define FTS_NSOK 11 /* no stat(2) requested */ | |
| 176 # define FTS_SL 12 /* symbolic link */ | |
| 177 # define FTS_SLNONE 13 /* symbolic link without target */ | |
| 178 # define FTS_W 14 /* whiteout object */ | |
| 179 unsigned short int fts_info; /* user flags for FTSENT structure */ | |
| 180 | |
| 181 # define FTS_DONTCHDIR 0x01 /* don't chdir .. to the parent */ | |
| 182 # define FTS_SYMFOLLOW 0x02 /* followed a symlink to get here */ | |
| 183 unsigned short int fts_flags; /* private flags for FTSENT structure */ | |
| 184 | |
| 185 # define FTS_AGAIN 1 /* read node again */ | |
| 186 # define FTS_FOLLOW 2 /* follow symbolic link */ | |
| 187 # define FTS_NOINSTR 3 /* no instructions */ | |
| 188 # define FTS_SKIP 4 /* discard node */ | |
| 189 unsigned short int fts_instr; /* fts_set() instructions */ | |
| 190 | |
| 191 struct stat fts_statp[1]; /* stat(2) information */ | |
| 192 char fts_name[1]; /* file name */ | |
| 193 } FTSENT; | |
| 194 | |
| 195 __BEGIN_DECLS | |
| 196 FTSENT *fts_children (FTS *, int) __THROW; | |
| 197 int fts_close (FTS *) __THROW; | |
| 198 FTS *fts_open (char * const *, int, | |
| 199 int (*)(const FTSENT **, const FTSENT **)) __THROW; | |
| 200 FTSENT *fts_read (FTS *) __THROW; | |
| 201 int fts_set (FTS *, FTSENT *, int) __THROW; | |
| 202 __END_DECLS | |
| 203 | |
| 204 #endif /* fts.h */ |