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/*
* This file is part of the Green End SFTP Server.
* Copyright (C) 2007 Richard Kettlewell
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program 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
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
* USA
*/
#include "sftpcommon.h"
#include "utils.h"
#include "alloc.h"
#include "debug.h"
#include <unistd.h>
#include <errno.h>
char *sftp_do_readlink(struct allocator *a, const char *path) {
size_t nresult = 32, oldnresult = 0;
char *result = 0;
int n;
/* readlink(2) has a rather stupid interface */
while(nresult > 0 && nresult <= 65536) {
result = sftp_alloc_more(a, result, oldnresult, nresult);
n = readlink(path, result, nresult);
if(n < 0)
return 0;
if((unsigned)n < nresult) {
result[n] = 0;
return result;
}
oldnresult = nresult;
nresult *= 2;
}
/* We should have wasted at most about 128Kbyte if we get here,
* perhaps less due to use of sftp_alloc_more(). If you have symlinks
* with targets bigger than 64K then (i) you'll need to update the
* bound above (ii) what color is the sky on your planet? */
errno = E2BIG;
return 0;
}
/*
Local Variables:
c-basic-offset:2
comment-column:40
fill-column:79
indent-tabs-mode:nil
End:
*/
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