xref: /netbsd-src/usr.bin/vndcompress/common.h (revision b7b7574d3bf8eeb51a1fa3977b59142ec6434a55)
1 /*	$NetBSD: common.h,v 1.6 2014/01/22 06:18:00 riastradh Exp $	*/
2 
3 /*-
4  * Copyright (c) 2013 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_COMMON_H
33 #define	VNDCOMPRESS_COMMON_H
34 
35 #include <sys/cdefs.h>
36 #include <sys/param.h>
37 
38 #include <limits.h>
39 #include <stdint.h>
40 
41 #ifndef __type_fit
42 
43 /* XXX Cruft from HEAD.  */
44 
45 #define __type_mask(t) (/*LINTED*/sizeof(t) < sizeof(intmax_t) ? \
46     (~((1ULL << (sizeof(t) * NBBY)) - 1)) : 0ULL)
47 
48 #define __zeroll() (0LL)
49 #define __negative_p(x) ((x) < 0)
50 
51 #define __type_min_s(t) ((t)((1ULL << (sizeof(t) * NBBY - 1))))
52 #define __type_max_s(t) ((t)~((1ULL << (sizeof(t) * NBBY - 1))))
53 #define __type_min_u(t) ((t)0ULL)
54 #define __type_max_u(t) ((t)~0ULL)
55 #define __type_is_signed(t) (/*LINTED*/__type_min_s(t) + (t)1 < (t)1)
56 #define __type_min(t) (__type_is_signed(t) ? __type_min_s(t) : __type_min_u(t))
57 #define __type_max(t) (__type_is_signed(t) ? __type_max_s(t) : __type_max_u(t))
58 
59 
60 #define __type_fit_u(t, a) (/*LINTED*/sizeof(t) < sizeof(intmax_t) ? \
61     (((a) & __type_mask(t)) == 0) : !__negative_p(a))
62 
63 #define __type_fit_s(t, a) (/*LINTED*/__negative_p(a) ? \
64     ((intmax_t)((a) + __zeroll()) >= (intmax_t)__type_min_s(t)) : \
65     ((intmax_t)((a) + __zeroll()) <= (intmax_t)__type_max_s(t)))
66 
67 /*
68  * return true if value 'a' fits in type 't'
69  */
70 #define __type_fit(t, a) (__type_is_signed(t) ? \
71     __type_fit_s(t, a) : __type_fit_u(t, a))
72 
73 #endif
74 
75 /* XXX urk */
76 #ifndef OFF_MAX
77 #define	OFF_MAX			__type_max(off_t)
78 #endif
79 
80 /* XXX Why is this kernel-only?  */
81 #define	SET(t, f)	((t) |= (f))
82 #define	CLR(t, f)	((t) &= ~(f))
83 #define	ISSET(t, f)	((t) & (f))
84 
85 /*
86  * We require:
87  *
88  *   0 < blocksize			(duh)
89  *   blocksize % DEV_BSIZE == 0		(for kernel use)
90  *
91  *   blocksize <= UINT32_MAX		(per the format)
92  *   blocksize*2 <= SIZE_MAX		(for a compression buffer)
93  *   blocksize*2 <= ULONG_MAX		(for zlib API)
94  */
95 #define	MIN_BLOCKSIZE		DEV_BSIZE
96 #define	DEF_BLOCKSIZE		0x10000
97 #define	MAX_BLOCKSIZE							\
98 	rounddown(MIN(UINT32_MAX, (MIN(SIZE_MAX, ULONG_MAX) / 2)),	\
99 	    MIN_BLOCKSIZE)
100 
101 /*
102  * We require:
103  *
104  *   n_offsets * sizeof(uint64_t) <= SIZE_MAX	(array of 64-bit offsets)
105  *   n_blocks = (n_offsets + 1)		(extra offset to set last block end)
106  *   n_blocks <= UINT32_MAX		(per the format)
107  *   n_offsets <= UINT32_MAX		(for the sake of simplicity)
108  */
109 #define	MAX_N_BLOCKS							\
110 	(MIN(UINT32_MAX, (SIZE_MAX / sizeof(uint64_t))) - 1)
111 #define	MAX_N_OFFSETS		(MAX_N_BLOCKS + 1)
112 
113 /*
114  * The window size is at most the number of offsets, so it has the same
115  * maximum bound.  The default window size is chosen so that windows
116  * fit in one 4096-byte page of memory.  We could use 64k bytes, or
117  * st_blksize, to maximize I/O transfer size, but the transfers won't
118  * be aligned without a lot of extra work.
119  */
120 #define	MAX_WINDOW_SIZE		MAX_N_OFFSETS
121 #define	DEF_WINDOW_SIZE		512
122 
123 struct cloop2_header {
124 	char		cl2h_magic[128];
125 	uint32_t	cl2h_blocksize;
126 	uint32_t	cl2h_n_blocks;
127 } __packed;
128 
129 #define	CLOOP2_OFFSET_TABLE_OFFSET	136
130 
131 struct options {
132 	int		flags;
133 #define	FLAG_c	0x0001	/* Compress */
134 #define	FLAG_d	0x0002	/* Decompress */
135 #define	FLAG_p	0x0004	/* Partial */
136 #define	FLAG_r	0x0008	/* Restart */
137 #define	FLAG_b	0x0010	/* Block size */
138 #define	FLAG_R	0x0020	/* abort on Restart failure */
139 #define	FLAG_k	0x0040	/* checKpoint blocks */
140 #define	FLAG_l	0x0080	/* Length of input */
141 #define	FLAG_w	0x0100	/* Window size */
142 	uint32_t	blocksize;
143 	uint32_t	end_block;	/* end for partial transfer */
144 	uint32_t	checkpoint_blocks;	/* blocks before checkpoint */
145 	uint64_t	length;			/* length of image in bytes */
146 	uint32_t	window_size;	/* size of window into offset table */
147 };
148 
149 int	vndcompress(int, char **, const struct options *);
150 int	vnduncompress(int, char **, const struct options *);
151 void	usage(void) __dead;
152 
153 static const char cloop2_magic[] = "\
154 #!/bin/sh\n\
155 #V2.0 Format\n\
156 insmod cloop.o file=$0 && mount -r -t iso9660 /dev/cloop $1\n\
157 exit $?\n\
158 ";
159 
160 #endif	/* VNDCOMPRESS_COMMON_H */
161