/*
 * Copyright (c) 2002, 2004, 2005 Sendmail, Inc. and its suppliers.
 *	All rights reserved.
 *
 * By using this file, you agree to the terms and conditions set
 * forth in the LICENSE file which can be found at the top level of
 * the sendmail distribution.
 */

#include "sm/generic.h"
SM_RCSID("@(#)$Id: strcatmv.c,v 1.13 2005/06/02 19:00:37 ca Exp $")

#include "sm/assert.h"
#include "sm/magic.h"
#include "sm/rpool.h"
#include "sm/varargs.h"
#include "sm/limits.h"
#include "sm/str.h"
#include "sm/str-int.h"

/*
**  SM_STR_CATMV -- Append multiple strings to dst (only if it fits)
**	This version creates a full copy or none.
**
**	Parameters:
**		dst -- str destination
**		n -- number of source strings
**		... -- str to append
**		(should we use NULL as end marker instead?)
**
**	Returns:
**		usual sm_error code; ENOMEM, SM_E_OVFLW_SC, SM_E_OVFLW_NS
*/

sm_ret_T
sm_str_catmv(sm_str_P dst, int n, ...)
{
	int h;
	uint total, prev;
	sm_ret_T res;
	sm_str_P str;
	va_list ap;

	SM_IS_BUF(dst);
	va_start(ap, n);

	/*
	**  Compute length first and see whether it exceeds max.
	**  That would also allow to resize the destination string
	**  only once.
	**  Disadvantage: walks twice through the args.
	*/

	h = n;
	total = 0;
	prev = 0;

	/* loop through all source strings */
	while (h-- > 0)
	{
		str = va_arg(ap, sm_str_P);
		SM_IS_BUF(str);
		total += sm_str_getlen(str);
		if (sm_str_getlen(str) != 0 &&
		    (total > sm_str_getmax(dst) || total < prev))
		{
			va_end(ap);
			return sm_error_perm(SM_EM_STR, SM_E_OVFLW_NS);
		}
		prev = total;
	}
	va_end(ap);
	va_start(ap, n);
	if (total > dst->sm_str_size)
		SM_STR_INCREASE_R(dst, total);

	/* loop through all source strings */
	while (n-- > 0)
	{
		str = va_arg(ap, sm_str_P);
		res = sm_str_cat(dst, str);
		if (sm_is_err(res))
		{
			va_end(ap);
			return res;
		}
	}
	va_end(ap);
	return SM_SUCCESS;
}