summaryrefslogtreecommitdiff
path: root/io/ftw.c
blob: d7ec7169362f64db76aecf5f9f8b8a40c65fec12 (plain)
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
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
/* Copyright (C) 1992, 1995, 1996, 1997 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Ian Lance Taylor (ian@airs.com).

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public License as
   published by the Free Software Foundation; either version 2 of the
   License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If not,
   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */

#include <errno.h>
#include <limits.h>
#include <stdlib.h>
#include <string.h>
#include <dirent.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <ftw.h>


#ifndef PATH_MAX
#define PATH_MAX 1024		/* XXX */
#endif


/* Traverse one level of a directory tree.  */

static int
ftw_dir (DIR **dirs, int level, int descriptors, char *dir, size_t len,
	 int (*func) (const char *file, const struct stat *status, int flag))
{
  int got;
  struct dirent *entry;

  got = 0;

  __set_errno (0);

  while ((entry = readdir (dirs[level])) != NULL)
    {
      struct stat s;
      int flag, retval, newlev;
      size_t namlen;

      ++got;

      if (entry->d_name[0] == '.'
	  && (entry->d_name[1] == '\0' ||
	      (entry->d_name[1] == '.' && entry->d_name[2] == '\0')))
	{
	  __set_errno (0);
	  continue;
	}

      namlen = _D_EXACT_NAMLEN (entry);

      if (namlen + len + 1 > PATH_MAX)
	{
#ifdef ENAMETOOLONG
	  __set_errno (ENAMETOOLONG);
#else
	  __set_errno (ENOMEM);
#endif
	  return -1;
	}

      dir[len] = '/';
      memcpy ((void *) (dir + len + 1), (void *) entry->d_name,
	      namlen + 1);

      if (stat (dir, &s) < 0)
	{
	  if (errno != EACCES && errno != ENOENT)
	    return -1;
	  flag = FTW_NS;
	}
      else if (S_ISDIR (s.st_mode))
	{
	  newlev = (level + 1) % descriptors;

	  if (dirs[newlev] != NULL)
	    closedir (dirs[newlev]);

	  dirs[newlev] = opendir (dir);
	  if (dirs[newlev] != NULL)
	    flag = FTW_D;
	  else
	    {
	      if (errno != EACCES)
		return -1;
	      flag = FTW_DNR;
	    }
	}
      else
	flag = FTW_F;

      retval = (*func) (dir, &s, flag);

      if (flag == FTW_D)
	{
	  if (retval == 0)
	    retval = ftw_dir (dirs, newlev, descriptors, dir,
			      namlen + len + 1, func);
	  if (dirs[newlev] != NULL)
	    {
	      int save;

	      save = errno;
	      closedir (dirs[newlev]);
	      __set_errno (save);
	      dirs[newlev] = NULL;
	    }
	}

      if (retval != 0)
	return retval;

      if (dirs[level] == NULL)
	{
	  int skip;

	  dir[len] = '\0';
	  dirs[level] = opendir (dir);
	  if (dirs[level] == NULL)
	    return -1;
	  skip = got;
	  while (skip-- != 0)
	    {
	      __set_errno (0);
	      if (readdir (dirs[level]) == NULL)
		return errno == 0 ? 0 : -1;
	    }
	}

      __set_errno (0);
    }

  return errno == 0 ? 0 : -1;
}

/* Call a function on every element in a directory tree.  */

int
ftw (const char *dir,
     int (*func) (const char *file, const struct stat *status, int flag),
     int descriptors)
{
  DIR **dirs;
  size_t len;
  char buf[PATH_MAX + 1];
  struct stat s;
  int flag, retval;
  int i;

  if (descriptors <= 0)
    descriptors = 1;

  dirs = (DIR **) __alloca (descriptors * sizeof (DIR *));
  i = descriptors;
  while (i-- > 0)
    dirs[i] = NULL;

  if (stat (dir, &s) < 0)
    {
      if (errno != EACCES && errno != ENOENT)
	return -1;
      flag = FTW_NS;
    }
  else if (S_ISDIR (s.st_mode))
    {
      dirs[0] = opendir (dir);
      if (dirs[0] != NULL)
	flag = FTW_D;
      else
	{
	  if (errno != EACCES)
	    return -1;
	  flag = FTW_DNR;
	}
    }
  else
    flag = FTW_F;

  len = strlen (dir);
  memcpy ((void *) buf, (void *) dir, len + 1);

  retval = (*func) (buf, &s, flag);

  if (flag == FTW_D)
    {
      if (retval == 0)
	retval = ftw_dir (dirs, 0, descriptors, buf, len, func);
      if (dirs[0] != NULL)
	{
	  int save;

	  save = errno;
	  closedir (dirs[0]);
	  __set_errno (save);
	}
    }

  return retval;
}