/* This code is based on: */

/*	$OpenBSD: dirname.c,v 1.12 2005/03/02 12:27:26 millert Exp $	*/

/*
 * 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 "sm/generic.h"
SM_RCSID("@(#)$Id: sm_dirname.c,v 1.2 2005/04/27 23:46:01 ca Exp $")

#include "sm/assert.h"
#include "sm/error.h"
#include "sm/memops.h"
#include "sm/misc.h"

/*
**  SM_DIRNAME -- return directory (or "") of pathname
**	(always includes trailing "/" unless empty).
**
**	Parameters:
**		path -- some path name
**		basedir -- directory of path (output)
**		baselen -- length of basedir
**
**	Returns:
**		usual sm_error code
*/

sm_ret_T
sm_dirname(const char *path, char *basedir, size_t baselen)
{
	size_t len;
	const char *endp;

	SM_REQUIRE(basedir != NULL);
	SM_REQUIRE(baselen > 1);
	basedir[0] = '\0';

	/* Empty or NULL string gets treated as "" */
	if (path == NULL || *path == '\0')
		return SM_SUCCESS;

	/* 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)
	{
		if (*endp == '/')
		{
			basedir[0] = '/';
			basedir[1] = '\0';
		}
		else
			basedir[0] = '\0';
		return SM_SUCCESS;
	}
	else
	{
		/* Move forward past the separating slashes */
		while (endp > path && *endp == '/' && *(endp - 1) == '/')
			endp--;
	}

	len = endp - path + 1;
	if (len >= baselen)
		return sm_err_perm(ENAMETOOLONG);
	sm_memcpy(basedir, path, len);
	basedir[len] = '\0';
	return SM_SUCCESS;
}