blob: 43d380127d539bf9a317f3d0fff8d771e7291d34 [file] [log] [blame]
bellard3c565212004-09-29 21:29:14 +00001/*
bellard585d0ed2004-12-12 11:24:44 +00002 * QEMU Block driver for CLOOP images
ths5fafdf22007-09-16 21:08:06 +00003 *
bellard3c565212004-09-29 21:29:14 +00004 * Copyright (c) 2004 Johannes E. Schindelin
ths5fafdf22007-09-16 21:08:06 +00005 *
bellard3c565212004-09-29 21:29:14 +00006 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22 * THE SOFTWARE.
23 */
pbrookfaf07962007-11-11 02:51:17 +000024#include "qemu-common.h"
bellard3c565212004-09-29 21:29:14 +000025#include "block_int.h"
26#include <zlib.h>
27
28typedef struct BDRVCloopState {
29 int fd;
30 uint32_t block_size;
31 uint32_t n_blocks;
32 uint64_t* offsets;
33 uint32_t sectors_per_block;
34 uint32_t current_block;
bellard28a5c9c2006-02-01 21:43:52 +000035 uint8_t *compressed_block;
36 uint8_t *uncompressed_block;
bellard3c565212004-09-29 21:29:14 +000037 z_stream zstream;
38} BDRVCloopState;
39
40static int cloop_probe(const uint8_t *buf, int buf_size, const char *filename)
41{
42 const char* magic_version_2_0="#!/bin/sh\n"
43 "#V2.0 Format\n"
44 "modprobe cloop file=$0 && mount -r -t iso9660 /dev/cloop $1\n";
45 int length=strlen(magic_version_2_0);
46 if(length>buf_size)
47 length=buf_size;
48 if(!memcmp(magic_version_2_0,buf,length))
49 return 2;
50 return 0;
51}
52
bellard83f64092006-08-01 16:21:11 +000053static int cloop_open(BlockDriverState *bs, const char *filename, int flags)
bellard3c565212004-09-29 21:29:14 +000054{
55 BDRVCloopState *s = bs->opaque;
56 uint32_t offsets_size,max_compressed_block_size=1,i;
57
bellard83f64092006-08-01 16:21:11 +000058 s->fd = open(filename, O_RDONLY | O_BINARY);
bellard3c565212004-09-29 21:29:14 +000059 if (s->fd < 0)
bellard83f64092006-08-01 16:21:11 +000060 return -errno;
bellard3c565212004-09-29 21:29:14 +000061 bs->read_only = 1;
62
63 /* read header */
64 if(lseek(s->fd,128,SEEK_SET)<0) {
65cloop_close:
66 close(s->fd);
67 return -1;
68 }
69 if(read(s->fd,&s->block_size,4)<4)
70 goto cloop_close;
71 s->block_size=be32_to_cpu(s->block_size);
72 if(read(s->fd,&s->n_blocks,4)<4)
73 goto cloop_close;
74 s->n_blocks=be32_to_cpu(s->n_blocks);
75
76 /* read offsets */
77 offsets_size=s->n_blocks*sizeof(uint64_t);
78 if(!(s->offsets=(uint64_t*)malloc(offsets_size)))
79 goto cloop_close;
80 if(read(s->fd,s->offsets,offsets_size)<offsets_size)
81 goto cloop_close;
82 for(i=0;i<s->n_blocks;i++) {
83 s->offsets[i]=be64_to_cpu(s->offsets[i]);
84 if(i>0) {
85 uint32_t size=s->offsets[i]-s->offsets[i-1];
86 if(size>max_compressed_block_size)
87 max_compressed_block_size=size;
88 }
89 }
90
91 /* initialize zlib engine */
bellard28a5c9c2006-02-01 21:43:52 +000092 if(!(s->compressed_block = malloc(max_compressed_block_size+1)))
bellard3c565212004-09-29 21:29:14 +000093 goto cloop_close;
bellard28a5c9c2006-02-01 21:43:52 +000094 if(!(s->uncompressed_block = malloc(s->block_size)))
bellard3c565212004-09-29 21:29:14 +000095 goto cloop_close;
96 if(inflateInit(&s->zstream) != Z_OK)
97 goto cloop_close;
98 s->current_block=s->n_blocks;
ths3b46e622007-09-17 08:09:54 +000099
bellard3c565212004-09-29 21:29:14 +0000100 s->sectors_per_block = s->block_size/512;
101 bs->total_sectors = s->n_blocks*s->sectors_per_block;
102 return 0;
103}
104
105static inline int cloop_read_block(BDRVCloopState *s,int block_num)
106{
107 if(s->current_block != block_num) {
108 int ret;
109 uint32_t bytes = s->offsets[block_num+1]-s->offsets[block_num];
ths3b46e622007-09-17 08:09:54 +0000110
bellard3c565212004-09-29 21:29:14 +0000111 lseek(s->fd, s->offsets[block_num], SEEK_SET);
112 ret = read(s->fd, s->compressed_block, bytes);
ths5fafdf22007-09-16 21:08:06 +0000113 if (ret != bytes)
bellard3c565212004-09-29 21:29:14 +0000114 return -1;
ths5fafdf22007-09-16 21:08:06 +0000115
bellard3c565212004-09-29 21:29:14 +0000116 s->zstream.next_in = s->compressed_block;
117 s->zstream.avail_in = bytes;
118 s->zstream.next_out = s->uncompressed_block;
119 s->zstream.avail_out = s->block_size;
120 ret = inflateReset(&s->zstream);
121 if(ret != Z_OK)
122 return -1;
123 ret = inflate(&s->zstream, Z_FINISH);
124 if(ret != Z_STREAM_END || s->zstream.total_out != s->block_size)
125 return -1;
ths5fafdf22007-09-16 21:08:06 +0000126
bellard3c565212004-09-29 21:29:14 +0000127 s->current_block = block_num;
128 }
129 return 0;
130}
131
ths5fafdf22007-09-16 21:08:06 +0000132static int cloop_read(BlockDriverState *bs, int64_t sector_num,
bellard3c565212004-09-29 21:29:14 +0000133 uint8_t *buf, int nb_sectors)
134{
135 BDRVCloopState *s = bs->opaque;
136 int i;
137
138 for(i=0;i<nb_sectors;i++) {
139 uint32_t sector_offset_in_block=((sector_num+i)%s->sectors_per_block),
140 block_num=(sector_num+i)/s->sectors_per_block;
141 if(cloop_read_block(s, block_num) != 0)
142 return -1;
143 memcpy(buf+i*512,s->uncompressed_block+sector_offset_in_block*512,512);
144 }
145 return 0;
146}
147
148static void cloop_close(BlockDriverState *bs)
149{
150 BDRVCloopState *s = bs->opaque;
151 close(s->fd);
bellard585d0ed2004-12-12 11:24:44 +0000152 if(s->n_blocks>0)
153 free(s->offsets);
bellard3c565212004-09-29 21:29:14 +0000154 free(s->compressed_block);
155 free(s->uncompressed_block);
156 inflateEnd(&s->zstream);
157}
158
159BlockDriver bdrv_cloop = {
160 "cloop",
161 sizeof(BDRVCloopState),
162 cloop_probe,
163 cloop_open,
164 cloop_read,
165 NULL,
166 cloop_close,
167};
168
169