adtools/clib2

/*
 * $Id: libgen_dirname.c,v 1.8 2006-10-02 07:15:37 obarthel Exp $
 *
 * :ts=4
 *
 * Portable ISO 'C' (1994) runtime library for the Amiga computer
 * Copyright (c) 2002-2015 by Olaf Barthel <obarthel (at) gmx.net>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   - Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   - Neither the name of Olaf Barthel nor the names of 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.
 */

#include <string.h>
#include <libgen.h>
#include <stdio.h>

/****************************************************************************/

#include "debug.h"

/****************************************************************************/

/* The following is not part of the ISO 'C' (1994) standard. */

/****************************************************************************/

char *
dirname(const char *path)
{
    static char new_path[MAXPATHLEN];
    const char * str;
    char * result;
    size_t len;

    ENTER();

    if(path == NULL)
        SHOWPOINTER(path);
    else
        SHOWSTRING(path);

    /* An empty path always comes out as the "current directory". */
    str = ".";
    len = 1;

    if(path != NULL && path[0] != '\0')
    {
        /* Strip all trailing slashes. */
        len = strlen(path);
        while(len > 1 && path[len-1] == '/')
            len--;

        /* Is there anything left? */
        if(len > 0)
        {
            size_t i;

            for(i = len-1 ;  ; i--)
            {
                if(path[i] == '/')
                {
                    /* Return everything up to, but not including
                       the last slash in the path. That's usually
                       the directory name. */
                    str = path;
                    len = i;

                    /* If that produces an empty string, it means
                       that the entire string consists of slash
                       characters. We'll return only the first. */
                    if(i == 0)
                        len++;

                    break;
                }

                if(i == 0)
                    break;
            }
        }
    }

    /* Truncate the path name we can return. This function always returns
       a valid pointer rather than NULL because some software expects it
       to do so (I blame the specifications). */
    if(len >= sizeof(new_path))
        len = sizeof(new_path)-1;

    memcpy(new_path,str,len);
    new_path[len] = '\0';

    result = new_path;

    RETURN(result);
    return(result);
}