1 /* xgetcwd.c -- return current directory with unlimited length
3 Copyright (C) 1992, 1996, 2000, 2001, 2003, 2004 Free Software
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software Foundation,
18 Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
20 /* Written by David MacKenzie <djm@gnu.ai.mit.edu>. */
29 #include <sys/types.h>
40 # define INITIAL_BUFFER_SIZE (PATH_MAX + 1)
42 # define getcwd(Buf, Max) getwd (Buf)
48 /* Return the current directory, newly allocated, assuming it fits
49 within PATH_MAX bytes -- this is a common system-imposed limit
51 Upon an out-of-memory error, call xalloc_die.
52 Upon any other type of error, return NULL. */
58 char *cwd = getcwd (NULL, 0);
59 if (! cwd && errno == ENOMEM)
66 /* The initial buffer size for the working directory. A power of 2
67 detects arithmetic overflow earlier, but is not required. */
68 # ifndef INITIAL_BUFFER_SIZE
69 # define INITIAL_BUFFER_SIZE 128
72 size_t buf_size = INITIAL_BUFFER_SIZE;
76 char *buf = xmalloc (buf_size);
77 char *cwd = getcwd (buf, buf_size);
82 if (saved_errno != ERANGE)
86 if (PATH_MAX / 2 < buf_size)
88 if (PATH_MAX <= buf_size)