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/****************************************************************************
* lib/lib_getcwd.c
*
* Copyright (C) 2008 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/types.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)
/****************************************************************************
* Definitions
****************************************************************************/
/****************************************************************************
* Public Variables
****************************************************************************/
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: getwcd
*
* Description:
* getcwd() function places the absolute pathname of the current working
* directory in the array pointed to by 'buf', and returns 'buf.' The
* pathname copied to the array shall contain no components that are
* symbolic links. The 'size' argument is the size in bytes of the
* character array pointed to by the 'buf' argument.
*
* Input Parmeters:
* buf - a pointer to the location in which the current working directory
* pathaname is returned.
* size - The size in bytes avaiable at 'buf'
*
* Returned Value:
* Upon successful completion, getcwd() returns the 'buf' argument.
* Otherwise, getcwd() returns a null pointer and sets errno to indicate
* the error:
*
* EINVAL
* The 'size' argument is 0 or the 'buf' argument is NULL.
* ERANGE
* The size argument is greater than 0, but is smaller than the length
* of the currrent working directory pathname +1.
* EACCES
* Read or search permission was denied for a component of the pathname.
* ENOMEM
* Insufficient storage space is available.
*
****************************************************************************/
FAR char *getcwd(FAR char *buf, size_t size)
{
char *pwd;
/* Verify input parameters */
if (!buf || !size)
{
errno = EINVAL;
return NULL;
}
/* If no working directory is defined, then default to the home directory */
pwd = getenv("PWD");
if (!pwd)
{
pwd = CONFIG_LIB_HOMEDIR;
}
/* Verify that the cwd will fit into the user-provided buffer */
if (strlen(pwd) + 1 > size)
{
errno = ERANGE;
return NULL;
}
/* Copy the cwd to the user buffer */
strcpy(buf, pwd);
sched_unlock();
return buf;
}
#endif /* CONFIG_NFILE_DESCRIPTORS && !CONFIG_DISABLE_ENVIRON */
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