lib/fts_.h

   1 /* Traverse a file hierarchy.
   2
   3    Copyright (C) 2004 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, 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>
  55 # else
  56 #  undef __THROW
  57 #  define __THROW
  58 #  undef __BEGIN_DECLS
  59 #  define __BEGIN_DECLS
  60 #  undef __END_DECLS
  61 #  define __END_DECLS
  62 # endif
  63
  64 # include <stddef.h>
  65 # include <sys/types.h>
  66 # include "hash.h"
  67 # include "cycle-check.h"
  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 # */
  74         char *fts_path;                 /* path for this descent */
  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) (const void *, const void *); /* compare fn */
  79
  80 # define FTS_COMFOLLOW  0x0001          /* follow command line symlinks */
  81 # define FTS_LOGICAL    0x0002          /* logical walk */
  82 # define FTS_NOCHDIR    0x0004          /* don't change directories */
  83 # define FTS_NOSTAT     0x0008          /* don't get stat info */
  84 # define FTS_PHYSICAL   0x0010          /* physical walk */
  85 # define FTS_SEEDOT     0x0020          /* return dot and dot-dot */
  86 # define FTS_XDEV       0x0040          /* don't cross devices */
  87 # define FTS_WHITEOUT   0x0080          /* return whiteout information */
  88
  89   /* There are two ways to detect cycles.
  90      The lazy way, with which one may process a directory that is a
  91      part of the cycle several times before detecting the cycle.
  92      The `tight' way, whereby fts uses more memory (proportional
  93      to number of `active' directories, aka distance from root
  94      of current tree to current directory -- see active_dir_ht)
  95      to detect any cycle right away.  For example, du must use
  96      this option to avoid counting disk space in a cycle multiple
  97      times, but chown -R need not.
  98      The default is to use the constant-memory lazy way. */
  99 # define FTS_TIGHT_CYCLE_CHECK  0x0100
 100
 101 # define FTS_OPTIONMASK 0x01ff          /* valid user option mask */
 102
 103 # define FTS_NAMEONLY   0x1000          /* (private) child names only */
 104 # define FTS_STOP       0x2000          /* (private) unrecoverable error */
 105         int fts_options;                /* fts_open options, global flags */
 106
 107         /* This data structure records the directories between a starting
 108            point and the current directory.  I.e., a directory is recorded
 109            here IFF we have visited it once, but we have not yet completed
 110            processing of all its entries.  Every time we visit a new directory,
 111            we add that directory to this set.  When we finish with a directory
 112            (usually by visiting it a second time), we remove it from this
 113            set.  Each entry in this data structure is a device/inode pair.
 114            This data structure is used to detect directory cycles efficiently
 115            and promptly even when the depth of a hierarchy is in the tens
 116            of thousands.  Lazy checking, as done by GNU rm via cycle-check.c,
 117            wouldn't be appropriate for du.  */
 118         Hash_table *active_dir_ht;
 119         struct cycle_check_state *cycle_state;
 120 } FTS;
 121
 122 typedef struct _ftsent {
 123         struct _ftsent *fts_cycle;      /* cycle node */
 124         struct _ftsent *fts_parent;     /* parent directory */
 125         struct _ftsent *fts_link;       /* next file in directory */
 126         long fts_number;                /* local numeric value */
 127         void *fts_pointer;              /* local address value */
 128         char *fts_accpath;              /* access path */
 129         char *fts_path;                 /* root path */
 130         int fts_errno;                  /* errno for this node */
 131         int fts_symfd;                  /* fd for symlink */
 132         size_t fts_pathlen;             /* strlen(fts_path) */
 133
 134         ino_t fts_ino;                  /* inode */
 135         dev_t fts_dev;                  /* device */
 136         nlink_t fts_nlink;              /* link count */
 137
 138 # define FTS_ROOTPARENTLEVEL    (-1)
 139 # define FTS_ROOTLEVEL           0
 140         ptrdiff_t fts_level;            /* depth (-1 to N) */
 141
 142         size_t fts_namelen;             /* strlen(fts_name) */
 143
 144 # define FTS_D           1              /* preorder directory */
 145 # define FTS_DC          2              /* directory that causes cycles */
 146 # define FTS_DEFAULT     3              /* none of the above */
 147 # define FTS_DNR         4              /* unreadable directory */
 148 # define FTS_DOT         5              /* dot or dot-dot */
 149 # define FTS_DP          6              /* postorder directory */
 150 # define FTS_ERR         7              /* error; errno is set */
 151 # define FTS_F           8              /* regular file */
 152 # define FTS_INIT        9              /* initialized only */
 153 # define FTS_NS         10              /* stat(2) failed */
 154 # define FTS_NSOK       11              /* no stat(2) requested */
 155 # define FTS_SL         12              /* symbolic link */
 156 # define FTS_SLNONE     13              /* symbolic link without target */
 157 # define FTS_W          14              /* whiteout object */
 158         unsigned short int fts_info;    /* user flags for FTSENT structure */
 159
 160 # define FTS_DONTCHDIR   0x01           /* don't chdir .. to the parent */
 161 # define FTS_SYMFOLLOW   0x02           /* followed a symlink to get here */
 162         unsigned short int fts_flags;   /* private flags for FTSENT structure */
 163
 164 # define FTS_AGAIN       1              /* read node again */
 165 # define FTS_FOLLOW      2              /* follow symbolic link */
 166 # define FTS_NOINSTR     3              /* no instructions */
 167 # define FTS_SKIP        4              /* discard node */
 168         unsigned short int fts_instr;   /* fts_set() instructions */
 169
 170         struct stat fts_statp[1];       /* stat(2) information */
 171         char fts_name[1];               /* file name */
 172 } FTSENT;
 173
 174 __BEGIN_DECLS
 175 FTSENT  *fts_children (FTS *, int) __THROW;
 176 int      fts_close (FTS *) __THROW;
 177 FTS     *fts_open (char * const *, int,
 178                    int (*)(const FTSENT **, const FTSENT **)) __THROW;
 179 FTSENT  *fts_read (FTS *) __THROW;
 180 int      fts_set (FTS *, FTSENT *, int) __THROW;
 181 __END_DECLS
 182
 183 #endif /* fts.h */