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
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
|
/*
* QEMU Block driver for CLOOP images
*
* Copyright (c) 2004 Johannes E. Schindelin
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "qemu-common.h"
#include "block_int.h"
#include "module.h"
#include <zlib.h>
typedef struct BDRVCloopState {
int fd;
uint32_t block_size;
uint32_t n_blocks;
uint64_t* offsets;
uint32_t sectors_per_block;
uint32_t current_block;
uint8_t *compressed_block;
uint8_t *uncompressed_block;
z_stream zstream;
} BDRVCloopState;
static int cloop_probe(const uint8_t *buf, int buf_size, const char *filename)
{
const char* magic_version_2_0="#!/bin/sh\n"
"#V2.0 Format\n"
"modprobe cloop file=$0 && mount -r -t iso9660 /dev/cloop $1\n";
int length=strlen(magic_version_2_0);
if(length>buf_size)
length=buf_size;
if(!memcmp(magic_version_2_0,buf,length))
return 2;
return 0;
}
static int cloop_open(BlockDriverState *bs, const char *filename, int flags)
{
BDRVCloopState *s = bs->opaque;
uint32_t offsets_size,max_compressed_block_size=1,i;
s->fd = open(filename, O_RDONLY | O_BINARY);
if (s->fd < 0)
return -errno;
bs->read_only = 1;
/* read header */
if(lseek(s->fd,128,SEEK_SET)<0) {
cloop_close:
close(s->fd);
return -1;
}
if(read(s->fd,&s->block_size,4)<4)
goto cloop_close;
s->block_size=be32_to_cpu(s->block_size);
if(read(s->fd,&s->n_blocks,4)<4)
goto cloop_close;
s->n_blocks=be32_to_cpu(s->n_blocks);
/* read offsets */
offsets_size=s->n_blocks*sizeof(uint64_t);
s->offsets=(uint64_t*)qemu_malloc(offsets_size);
if(read(s->fd,s->offsets,offsets_size)<offsets_size)
goto cloop_close;
for(i=0;i<s->n_blocks;i++) {
s->offsets[i]=be64_to_cpu(s->offsets[i]);
if(i>0) {
uint32_t size=s->offsets[i]-s->offsets[i-1];
if(size>max_compressed_block_size)
max_compressed_block_size=size;
}
}
/* initialize zlib engine */
s->compressed_block = qemu_malloc(max_compressed_block_size+1);
s->uncompressed_block = qemu_malloc(s->block_size);
if(inflateInit(&s->zstream) != Z_OK)
goto cloop_close;
s->current_block=s->n_blocks;
s->sectors_per_block = s->block_size/512;
bs->total_sectors = s->n_blocks*s->sectors_per_block;
return 0;
}
static inline int cloop_read_block(BDRVCloopState *s,int block_num)
{
if(s->current_block != block_num) {
int ret;
uint32_t bytes = s->offsets[block_num+1]-s->offsets[block_num];
lseek(s->fd, s->offsets[block_num], SEEK_SET);
ret = read(s->fd, s->compressed_block, bytes);
if (ret != bytes)
return -1;
s->zstream.next_in = s->compressed_block;
s->zstream.avail_in = bytes;
s->zstream.next_out = s->uncompressed_block;
s->zstream.avail_out = s->block_size;
ret = inflateReset(&s->zstream);
if(ret != Z_OK)
return -1;
ret = inflate(&s->zstream, Z_FINISH);
if(ret != Z_STREAM_END || s->zstream.total_out != s->block_size)
return -1;
s->current_block = block_num;
}
return 0;
}
static int cloop_read(BlockDriverState *bs, int64_t sector_num,
uint8_t *buf, int nb_sectors)
{
BDRVCloopState *s = bs->opaque;
int i;
for(i=0;i<nb_sectors;i++) {
uint32_t sector_offset_in_block=((sector_num+i)%s->sectors_per_block),
block_num=(sector_num+i)/s->sectors_per_block;
if(cloop_read_block(s, block_num) != 0)
return -1;
memcpy(buf+i*512,s->uncompressed_block+sector_offset_in_block*512,512);
}
return 0;
}
static void cloop_close(BlockDriverState *bs)
{
BDRVCloopState *s = bs->opaque;
close(s->fd);
if(s->n_blocks>0)
free(s->offsets);
free(s->compressed_block);
free(s->uncompressed_block);
inflateEnd(&s->zstream);
}
static BlockDriver bdrv_cloop = {
.format_name = "cloop",
.instance_size = sizeof(BDRVCloopState),
.bdrv_probe = cloop_probe,
.bdrv_open = cloop_open,
.bdrv_read = cloop_read,
.bdrv_close = cloop_close,
};
static void bdrv_cloop_init(void)
{
bdrv_register(&bdrv_cloop);
}
block_init(bdrv_cloop_init);
|
