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/* Copyright (C) 2005 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <sysdep.h>
/* Rename the file OLD relative to OLDFD to NEW relative to NEWFD. */
int
renameat (oldfd, old, newfd, new)
int oldfd;
const char *old;
int newfd;
const char *new;
{
static const char procfd[] = "/proc/self/fd/%d/%s";
char *bufold = NULL;
if (oldfd != AT_FDCWD && old[0] != '/')
{
size_t filelen = strlen (old);
/* Buffer for the path name we are going to use. It consists of
- the string /proc/self/fd/
- the file descriptor number
- the file name provided.
The final NUL is included in the sizeof. A bit of overhead
due to the format elements compensates for possible negative
numbers. */
size_t buflen = sizeof (procfd) + sizeof (int) * 3 + filelen;
bufold = alloca (buflen);
__snprintf (bufold, buflen, procfd, oldfd, old);
old = bufold;
}
char *bufnew = NULL;
if (newfd != AT_FDCWD && new[0] != '/')
{
size_t filelen = strlen (new);
/* Buffer for the path name we are going to use. It consists of
- the string /proc/self/fd/
- the file descriptor number
- the file name provided.
The final NUL is included in the sizeof. A bit of overhead
due to the format elements compensates for possible negative
numbers. */
size_t buflen = sizeof (procfd) + sizeof (int) * 3 + filelen;
bufnew = alloca (buflen);
__snprintf (bufnew, buflen, procfd, newfd, new);
new = bufnew;
}
INTERNAL_SYSCALL_DECL (err);
int result = INTERNAL_SYSCALL (rename, err, 2, old, new);
if (__builtin_expect (INTERNAL_SYSCALL_ERROR_P (result, err), 0))
{
int errval = INTERNAL_SYSCALL_ERRNO (result, err);
if (errval == ENOTDIR && (bufnew != NULL || bufold != NULL))
{
/* This can mean either the file descriptor is invalid or
/proc is not mounted. */
struct stat64 st;
if (bufnew != NULL)
{
if (__fxstat64 (_STAT_VER, newfd, &st) != 0)
/* errno is already set correctly. */
return -1;
/* If /proc is not mounted there is nothing we can do. */
if (S_ISDIR (st.st_mode)
&& (__xstat64 (_STAT_VER, "/proc/self/fd", &st) != 0
|| !S_ISDIR (st.st_mode)))
{
errval = ENOSYS;
goto out;
}
}
if (bufold != NULL)
{
if (__fxstat64 (_STAT_VER, oldfd, &st) != 0)
/* errno is already set correctly. */
return -1;
/* If /proc is not mounted there is nothing we can do. */
if (S_ISDIR (st.st_mode)
&& (__xstat64 (_STAT_VER, "/proc/self/fd", &st) != 0
|| !S_ISDIR (st.st_mode)))
errval = ENOSYS;
}
}
out:
__set_errno (errval);
result = -1;
}
return result;
}
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