/****************************************************************************
* lib/unistd/lib_chdir.c
*
* Copyright (C) 2008-2009, 2011 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/stat.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include "lib_internal.h"
#if CONFIG_NFILE_DESCRIPTORS > 0 && !defined(CONFIG_DISABLE_ENVIRON)
/****************************************************************************
* Public Variables
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
/****************************************************************************
* Name: _trimdir
****************************************************************************/
#if 0
static inline void _trimdir(char *path)
{
/* Skip any trailing '/' characters (unless it is also the leading '/') */
int len = strlen(path) - 1;
while (len > 0 && path[len] == '/')
{
path[len] = '\0';
len--;
}
}
#else
# define _trimdir(p)
#endif
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: chdir
*
* Description:
* The chdir() function causes the directory named by the pathname pointed
* to by the 'path' argument to become the current working directory; that
* is, the starting point for path searches for pathnames not beginning
* with '/'.
*
* Input Parmeters:
* path - A pointer to a directory to use as the new current working
* directory
*
* Returned Value:
* 0(OK) on success; -1(ERROR) on failure with errno set appropriately:
*
* EACCES
* Search permission is denied for any component of the pathname.
* ELOOP
* A loop exists in symbolic links encountered during resolution of the
* 'path' argument OR more that SYMLOOP_MAX symbolic links in the
* resolution of the 'path' argument.
* ENAMETOOLONG
* The length of the path argument exceeds PATH_MAX or a pathname component
* is longer than NAME_MAX.
* ENOENT
* A component of 'path' does not name an existing directory or path is
* an empty string.
* ENOTDIR
* A component of the pathname is not a directory.
*
****************************************************************************/
int chdir(FAR const char *path)
{
struct stat buf;
char *oldpwd;
char *alloc;
int err;
int ret;
/* Verify the input parameters */
if (!path)
{
err = ENOENT;
goto errout;
}
/* Verify that 'path' refers to a directory */
ret = stat(path, &buf);
if (ret != 0)
{
err = ENOENT;
goto errout;
}
/* Something exists here... is it a directory? */
if (!S_ISDIR(buf.st_mode))
{
err = ENOTDIR;
goto errout;
}
/* Yes, it is a directory. Remove any trailing '/' characters from the path */
_trimdir(path);
/* Replace any preceding OLDPWD with the current PWD (this is to
* support 'cd -' in NSH)
*/
sched_lock();
oldpwd = getenv("PWD");
if (!oldpwd)
{
oldpwd = CONFIG_LIB_HOMEDIR;
}
alloc = strdup(oldpwd); /* kludge needed because environment is realloc'ed */
setenv("OLDPWD", alloc, TRUE);
free(alloc);
/* Set the cwd to the input 'path' */
setenv("PWD", path, TRUE);
sched_unlock();
return OK;
errout:
errno = err;
return ERROR;
}
#endif /* CONFIG_NFILE_DESCRIPTORS && !CONFIG_DISABLE_ENVIRON */
