1/*	$NetBSD: offtab.h,v 1.3 2017/04/16 23:50:40 riastradh Exp $	*/
2
3/*-
4 * Copyright (c) 2014 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Taylor R. Campbell.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#ifndef	VNDCOMPRESS_OFFTAB_H
33#define	VNDCOMPRESS_OFFTAB_H
34
35#include <sys/cdefs.h>
36
37#include <stdbool.h>
38#include <stdint.h>
39
40#include "common.h"
41
42struct offtab {
43	uint32_t	ot_n_offsets;
44	uint32_t	ot_window_size;
45	uint32_t	ot_window_start;
46	uint64_t	*ot_window;
47	uint32_t	ot_blkno;
48	int		ot_fd;
49	off_t		ot_fdpos;
50	void		(*ot_report)(const char *, ...) __printflike(1,2);
51	void		(*ot_reportx)(const char *, ...) __printflike(1,2);
52	enum offtab_mode {
53		OFFTAB_MODE_NONE,
54		OFFTAB_MODE_READ,
55		OFFTAB_MODE_WRITE,
56	}		ot_mode;
57};
58
59#define	OFFTAB_MAX_FDPOS						      \
60	((off_t)(MIN(OFF_MAX, UINT64_MAX) -				      \
61	    (off_t)MAX_N_OFFSETS*sizeof(uint64_t)))
62
63void		offtab_init(struct offtab *, uint32_t, uint32_t, int, off_t);
64void		offtab_destroy(struct offtab *);
65
66bool		offtab_transmogrify_read_to_write(struct offtab *, uint32_t);
67
68bool		offtab_reset_read(struct offtab *,
69		    void (*)(const char *, ...) __printflike(1,2),
70		    void (*)(const char *, ...) __printflike(1,2));
71bool		offtab_prepare_get(struct offtab *, uint32_t);
72uint64_t	offtab_get(struct offtab *, uint32_t);
73
74void		offtab_reset_write(struct offtab *);
75void		offtab_checkpoint(struct offtab *, uint32_t, int);
76#define	OFFTAB_CHECKPOINT_SYNC	1
77void		offtab_prepare_put(struct offtab *, uint32_t);
78void		offtab_put(struct offtab *, uint32_t, uint64_t);
79
80#endif	/* VNDCOMPRESS_OFFTAB_H */
81