/*
 * include/proto/hdr_idx.h
 * This file defines function prototypes for fast header indexation.
 *
 * Copyright (C) 2000-2011 Willy Tarreau - w@1wt.eu
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation, version 2.1
 * exclusively.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */

#ifndef _PROTO_HDR_IDX_H
#define _PROTO_HDR_IDX_H

#include <common/config.h>
#include <types/hdr_idx.h>

extern struct pool_head *pool_head_hdr_idx;

/*
 * Initialize the list pointers.
 * list->size must already be set. If list->size is set and list->v is
 * non-null, list->v is also initialized..
 */
static inline void hdr_idx_init(struct hdr_idx *list)
{
	if (list->size && list->v) {
		register struct hdr_idx_elem e = { .len=0, .cr=0, .next=0};
		list->v[0] = e;
	}
	list->tail = 0;
	list->used = list->last = 1;
}

/*
 * Return index of the first entry in the list. Usually, it means the index of
 * the first header just after the request or response. If zero is returned, it
 * means that the list is empty.
 */
static inline int hdr_idx_first_idx(const struct hdr_idx *list)
{
	return list->v[0].next;
}

/*
 * Return position of the first entry in the list. Usually, it means the
 * position of the first header just after the request, but it can also be the
 * end of the headers if the request has no header. hdr_idx_start_idx() should
 * be checked before to ensure there is a valid header.
 */
static inline int hdr_idx_first_pos(const struct hdr_idx *list)
{
	return list->v[0].len + list->v[0].cr + 1;
}

/*
 * Sets the information about the start line. Its length and the presence of
 * the CR are registered so that hdr_idx_first_pos() knows exactly where to
 * find the first header.
 */
static inline void hdr_idx_set_start(struct hdr_idx *list, int len, int cr)
{
	list->v[0].len = len;
	list->v[0].cr = cr;
}

/*
 * Add a header entry to <list> after element <after>. <after> is ignored when
 * the list is empty or full. Common usage is to set <after> to list->tail.
 *
 * Returns the position of the new entry in the list (from 1 to size-1), or 0
 * if the array is already full. An effort is made to fill the array linearly,
 * but once the last entry has been used, we have to search for unused blocks,
 * which takes much more time. For this reason, it's important to size is
 * appropriately.
 */
int hdr_idx_add(int len, int cr, struct hdr_idx *list, int after);

#endif /* _PROTO_HDR_IDX_H */

/*
 * Local variables:
 *  c-indent-level: 8
 *  c-basic-offset: 8
 * End:
 */