Colony » Colony Scout » Colony Scout OS

/*

 * Copyright (c) 1997, 2004 Todd C. Miller <Todd.Miller@courtesan.com>

 *

 * Permission to use, copy, modify, and distribute this software for any

 * purpose with or without fee is hereby granted, provided that the above

 * copyright notice and this permission notice appear in all copies.

 *

 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES

 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF

 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR

 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES

 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN

 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF

 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

 */

#include <errno.h>

#include <libgen.h>

#include <string.h>

#include <sys/param.h>

char *

dirname(const char *path)

{

        static char dname[MAXPATHLEN];

        size_t len;

        const char *endp;

        /* Empty or NULL string gets treated as "." */

        if (path == NULL || *path == '\0') {

                dname[0] = '.';

                dname[1] = '\0';

                return (dname);

        }

        /* Strip any trailing slashes */

        endp = path + strlen(path) - 1;

        while (endp > path && *endp == '/')

                endp--;

        /* Find the start of the dir */

        while (endp > path && *endp != '/')

                endp--;

        /* Either the dir is "/" or there are no slashes */

        if (endp == path) {

                dname[0] = *endp == '/' ? '/' : '.';

                dname[1] = '\0';

                return (dname);

        } else {

                /* Move forward past the separating slashes */

                do {

                        endp--;

                } while (endp > path && *endp == '/');

        }

        len = endp - path + 1;

        if (len >= sizeof(dname)) {

                errno = ENAMETOOLONG;

                return (NULL);

        }

        memcpy(dname, path, len);

        dname[len] = '\0';

        return (dname);

}