summaryrefslogtreecommitdiff
path: root/lib/sqfs/comp/lz4.c
blob: 35fd629f4384dd3f6d7ea4795a9b8b928743fa7b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
/* SPDX-License-Identifier: LGPL-3.0-or-later */
/*
 * lz4.c
 *
 * Copyright (C) 2019 David Oberhollenzer <goliath@infraroot.at>
 */
#define SQFS_BUILDING_DLL
#include "config.h"

#include <stdbool.h>
#include <stdlib.h>
#include <string.h>

#include <lz4.h>
#include <lz4hc.h>

#include "internal.h"

typedef struct {
	sqfs_compressor_t base;
	bool high_compression;
} lz4_compressor_t;

typedef struct {
	sqfs_u32 version;
	sqfs_u32 flags;
} lz4_options;

#define LZ4LEGACY 1

static int lz4_write_options(sqfs_compressor_t *base, sqfs_file_t *file)
{
	lz4_compressor_t *lz4 = (lz4_compressor_t *)base;
	lz4_options opt = {
		.version = htole32(LZ4LEGACY),
		.flags = htole32(lz4->high_compression ?
				 SQFS_COMP_FLAG_LZ4_HC : 0),
	};

	return sqfs_generic_write_options(file, &opt, sizeof(opt));
}

static int lz4_read_options(sqfs_compressor_t *base, sqfs_file_t *file)
{
	lz4_options opt;
	int ret;
	(void)base;

	ret = sqfs_generic_read_options(file, &opt, sizeof(opt));
	if (ret)
		return ret;

	opt.version = le32toh(opt.version);
	opt.flags = le32toh(opt.flags);

	if (opt.version != LZ4LEGACY)
		return SQFS_ERROR_UNSUPPORTED;

	return 0;
}

static ssize_t lz4_comp_block(sqfs_compressor_t *base, const sqfs_u8 *in,
			      size_t size, sqfs_u8 *out, size_t outsize)
{
	lz4_compressor_t *lz4 = (lz4_compressor_t *)base;
	int ret;

	if (lz4->high_compression) {
		ret = LZ4_compress_HC((void *)in, (void *)out,
				      size, outsize, LZ4HC_CLEVEL_MAX);
	} else {
		ret = LZ4_compress_default((void *)in, (void *)out,
					   size, outsize);
	}

	if (ret < 0)
		return SQFS_ERROR_COMPRESSOR;

	return ret;
}

static ssize_t lz4_uncomp_block(sqfs_compressor_t *base, const sqfs_u8 *in,
				size_t size, sqfs_u8 *out, size_t outsize)
{
	int ret;
	(void)base;

	ret = LZ4_decompress_safe((void *)in, (void *)out, size, outsize);

	if (ret < 0)
		return SQFS_ERROR_COMPRESSOR;

	return ret;
}

static sqfs_compressor_t *lz4_create_copy(sqfs_compressor_t *cmp)
{
	lz4_compressor_t *lz4 = malloc(sizeof(*lz4));

	if (lz4 == NULL)
		return NULL;

	memcpy(lz4, cmp, sizeof(*lz4));
	return (sqfs_compressor_t *)lz4;
}

static void lz4_destroy(sqfs_compressor_t *base)
{
	free(base);
}

sqfs_compressor_t *lz4_compressor_create(const sqfs_compressor_config_t *cfg)
{
	sqfs_compressor_t *base;
	lz4_compressor_t *lz4;

	if (cfg->flags & ~(SQFS_COMP_FLAG_LZ4_ALL |
			   SQFS_COMP_FLAG_GENERIC_ALL)) {
		return NULL;
	}

	lz4 = calloc(1, sizeof(*lz4));
	base = (sqfs_compressor_t *)lz4;
	if (lz4 == NULL)
		return NULL;

	lz4->high_compression = (cfg->flags & SQFS_COMP_FLAG_LZ4_HC) != 0;

	base->destroy = lz4_destroy;
	base->do_block = (cfg->flags & SQFS_COMP_FLAG_UNCOMPRESS) ?
		lz4_uncomp_block : lz4_comp_block;
	base->write_options = lz4_write_options;
	base->read_options = lz4_read_options;
	base->create_copy = lz4_create_copy;
	return base;
}