OpenCores
URL https://opencores.org/ocsvn/openrisc_2011-10-31/openrisc_2011-10-31/trunk

Subversion Repositories openrisc_2011-10-31

[/] [openrisc/] [trunk/] [rtos/] [rtems/] [c/] [src/] [lib/] [libc/] [getcwd.c] - Blame information for rev 173

Details | Compare with Previous | View Log

Line No. Rev Author Line
1 30 unneback
/*
2
 * Copyright (c) 1989, 1991 The Regents of the University of California.
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
 * 3. All advertising materials mentioning features or use of this software
14
 *    must display the following acknowledgement:
15
 *      This product includes software developed by the University of
16
 *      California, Berkeley and its contributors.
17
 * 4. Neither the name of the University nor the names of its contributors
18
 *    may be used to endorse or promote products derived from this software
19
 *    without specific prior written permission.
20
 *
21
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31
 * SUCH DAMAGE.
32
 *
33
 *  Copied from newlib 1.8.1.  RTEMS can not build all of the contents
34
 *  of the UNIX directory but we need this routine.
35
 *
36
 *  $Id: getcwd.c,v 1.2 2001-09-27 12:01:15 chris Exp $
37
 */
38
 
39
/*
40
 *  Added these when moved to RTEMS
41
 */
42
 
43
#define _stat     stat
44
#define _opendir  opendir
45
#define _fstat    fstat
46
#define _readdir  readdir
47
#define _closedir closedir
48
 
49
#if defined(LIBC_SCCS) && !defined(lint)
50
static char sccsid[] = "@(#)getcwd.c    5.11 (Berkeley) 2/24/91";
51
#endif /* LIBC_SCCS and not lint */
52
 
53
#include <sys/stat.h>
54
#include <errno.h>
55
#include <dirent.h>
56
#include <stdio.h>
57
#include <stdlib.h>
58
#include <string.h>
59
#include <unistd.h>
60
#include <reent.h>
61
#include <_syslist.h>
62
 
63
#define bcopy(a,b,c)    memmove (b,a,c)
64
 
65
#define ISDOT(dp) \
66
        (dp->d_name[0] == '.' && (dp->d_name[1] == '\0' || \
67
            (dp->d_name[1] == '.' && dp->d_name[2] == '\0')))
68
 
69
#ifndef _REENT_ONLY
70
 
71
char *
72
getcwd (pt, size)
73
     char *pt;
74
     size_t size;
75
{
76
  register struct dirent *dp;
77
  register DIR *dir;
78
  register dev_t dev;
79
  register ino_t ino;
80
  register int first;
81
  register char *bpt, *bup;
82
  struct stat s;
83
  dev_t root_dev;
84
  ino_t root_ino;
85
  size_t ptsize, upsize;
86
  int save_errno;
87
  char *ept, *eup, *up;
88
 
89
  /*
90
   * If no buffer specified by the user, allocate one as necessary.
91
   * If a buffer is specified, the size has to be non-zero.  The path
92
   * is built from the end of the buffer backwards.
93
   */
94
 
95
  if (pt)
96
    {
97
      ptsize = 0;
98
      if (!size)
99
        {
100
          errno = EINVAL;
101
          return (char *) NULL;
102
        }
103
      ept = pt + size;
104
    }
105
  else
106
    {
107
      if (!(pt = (char *) malloc (ptsize = 1024 - 4)))
108
        {
109
          return (char *) NULL;
110
        }
111
      ept = pt + ptsize;
112
    }
113
  bpt = ept - 1;
114
  *bpt = '\0';
115
 
116
  /*
117
   * Allocate bytes (1024 - malloc space) for the string of "../"'s.
118
   * Should always be enough (it's 340 levels).  If it's not, allocate
119
   * as necessary.  Special * case the first stat, it's ".", not "..".
120
   */
121
 
122
  if (!(up = (char *) malloc (upsize = 1024 - 4)))
123
    {
124
      goto err;
125
    }
126
  eup = up + MAXPATHLEN;
127
  bup = up;
128
  up[0] = '.';
129
  up[1] = '\0';
130
 
131
  /* Save root values, so know when to stop. */
132
  if (stat ("/", &s))
133
    goto err;
134
  root_dev = s.st_dev;
135
  root_ino = s.st_ino;
136
 
137
  errno = 0;                     /* XXX readdir has no error return. */
138
 
139
  for (first = 1;; first = 0)
140
    {
141
      /* Stat the current level. */
142
      if (_stat (up, &s))
143
        goto err;
144
 
145
      /* Save current node values. */
146
      ino = s.st_ino;
147
      dev = s.st_dev;
148
 
149
      /* Check for reaching root. */
150
      if (root_dev == dev && root_ino == ino)
151
        {
152
          *--bpt = '/';
153
          /*
154
           * It's unclear that it's a requirement to copy the
155
           * path to the beginning of the buffer, but it's always
156
           * been that way and stuff would probably break.
157
           */
158
          (void) bcopy (bpt, pt, ept - bpt);
159
          free (up);
160
          return pt;
161
        }
162
 
163
      /*
164
       * Build pointer to the parent directory, allocating memory
165
       * as necessary.  Max length is 3 for "../", the largest
166
       * possible component name, plus a trailing NULL.
167
       */
168
 
169
      if (bup + 3 + MAXNAMLEN + 1 >= eup)
170
        {
171
          if (!(up = (char *) realloc (up, upsize *= 2)))
172
            {
173
              goto err;
174
            }
175
          bup = up;
176
          eup = up + upsize;
177
        }
178
      *bup++ = '.';
179
      *bup++ = '.';
180
      *bup = '\0';
181
 
182
      /* Open and stat parent directory. */
183
      if (!(dir = _opendir (up)) || _fstat (__dirfd (dir), &s))
184
        goto err;
185
 
186
      /* Add trailing slash for next directory. */
187
      *bup++ = '/';
188
 
189
      /*
190
       * If it's a mount point, have to stat each element because
191
       * the inode number in the directory is for the entry in the
192
       * parent directory, not the inode number of the mounted file.
193
       */
194
 
195
      save_errno = 0;
196
      if (s.st_dev == dev)
197
        {
198
          for (;;)
199
            {
200
              if (!(dp = _readdir (dir)))
201
                goto notfound;
202
              if (dp->d_ino == ino)
203
                break;
204
            }
205
        }
206
      else
207
        for (;;)
208
          {
209
            if (!(dp = _readdir (dir)))
210
              goto notfound;
211
            if (ISDOT (dp))
212
              continue;
213
            bcopy (dp->d_name, bup, strlen (dp->d_name) + 1);
214
 
215
            /* Save the first error for later. */
216
            if (stat (up, &s))
217
              {
218
                if (!save_errno)
219
                  save_errno = errno;
220
                errno = 0;
221
                continue;
222
              }
223
            if (s.st_dev == dev && s.st_ino == ino)
224
              break;
225
          }
226
 
227
      /*
228
       * Check for length of the current name, preceding slash,
229
       * leading slash.
230
       */
231
 
232
      if (bpt - pt <= strlen (dp->d_name) + (first ? 1 : 2))
233
        {
234
          size_t len, off;
235
 
236
          if (!ptsize)
237
            {
238
              errno = ERANGE;
239
              goto err;
240
            }
241
          off = bpt - pt;
242
          len = ept - bpt;
243
          if (!(pt = (char *) realloc (pt, ptsize *= 2)))
244
            {
245
              goto err;
246
            }
247
          bpt = pt + off;
248
          ept = pt + ptsize;
249
          (void) bcopy (bpt, ept - len, len);
250
          bpt = ept - len;
251
        }
252
      if (!first)
253
        *--bpt = '/';
254
      bpt -= strlen (dp->d_name);
255
      bcopy (dp->d_name, bpt, strlen (dp->d_name));
256
      (void) _closedir (dir);
257
 
258
      /* Truncate any file name. */
259
      *bup = '\0';
260
    }
261
 
262
notfound:
263
  /*
264
   * If readdir set errno, use it, not any saved error; otherwise,
265
   * didn't find the current directory in its parent directory, set
266
   * errno to ENOENT.
267
   */
268
 
269
  if (!errno)
270
    errno = save_errno ? save_errno : ENOENT;
271
  /* FALLTHROUGH */
272
 
273
err:
274
  if (ptsize)
275
    free (pt);
276
  free (up);
277
  return (char *) NULL;
278
}
279
 
280
#endif /* _REENT_ONLY */

powered by: WebSVN 2.1.0

© copyright 1999-2024 OpenCores.org, equivalent to Oliscience, all rights reserved. OpenCores®, registered trademark.