/****************************************************************************
* lib_dirname.c
*
* Copyright (C) 2007 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 Gregory Nutt 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.
*
****************************************************************************/
/****************************************************************************
* Compilation Switches
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <string.h>
#include <libgen.h>
/****************************************************************************
* Private Data
****************************************************************************/
static char g_retchar[2];
/****************************************************************************
* Global Functions
****************************************************************************/
/****************************************************************************
* Function: dirname
*
* Description:
* dirname() extracts the directory component from a null-terminated
* pathname string. In the usual case, dirname() returns the string up
* to, but not including, the final '/'. Trailing '/' characters are not
* counted as part of the pathname.
*
* If path does not contain a slash, dirname() returns the string ".". If
* path is the string "/", then dirname() returns the string "/". If path
* is a NULL pointer or points to an empty string, then dirname() returns
* the string ".".
*
* dirname() may modify the contents of path, so copies should be passed.
* dirname() may return pointers to statically allocated memory which may
* be overwritten by subsequent calls.
*
* Parameter:
* path The null-terminated string referring to the path to be decomposed
*
* Return:
* On success the directory component of the path is returned.
*
****************************************************************************/
char *dirname(char *path)
{
char *p;
int len;
int ch;
/* Handle some corner cases */
if (!path || *path == '\0')
{
ch = '.';
goto out_retchar;
}
/* Check for trailing slash characters */
len = strlen(path);
while (path[len-1] == '/')
{
/* Remove trailing '/' UNLESS this would make a zero length string */
if (len > 1)
{
path[len-1] = '\0';
len--;
}
else
{
ch = '/';
goto out_retchar;
}
}
/* Get the address of the last '/' which is not at the end of the path and,
* therefor, must be the end of the directory component.
*/
p = strrchr(path, '/');
if (p)
{
/* Handle the case where the only '/' in the string is the at the beginning
* of the path.
*/
if (p == path)
{
ch = '/';
goto out_retchar;
}
/* No, the directory component is the substring before the '/'. */
*p = '\0';
return path;
}
/* There is no '/' in the path */
ch = '.';
out_retchar:
g_retchar[0] = ch;
g_retchar[1] = '\0';
return g_retchar;
}
