usb-bsd: convert to QOM
[qemu.git] / block / dmg.c
1 /*
2 * QEMU Block driver for DMG images
3 *
4 * Copyright (c) 2004 Johannes E. Schindelin
5 *
6 * 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 */
24 #include "qemu-common.h"
25 #include "block_int.h"
26 #include "bswap.h"
27 #include "module.h"
28 #include <zlib.h>
29
30 typedef struct BDRVDMGState {
31 CoMutex lock;
32 /* each chunk contains a certain number of sectors,
33 * offsets[i] is the offset in the .dmg file,
34 * lengths[i] is the length of the compressed chunk,
35 * sectors[i] is the sector beginning at offsets[i],
36 * sectorcounts[i] is the number of sectors in that chunk,
37 * the sectors array is ordered
38 * 0<=i<n_chunks */
39
40 uint32_t n_chunks;
41 uint32_t* types;
42 uint64_t* offsets;
43 uint64_t* lengths;
44 uint64_t* sectors;
45 uint64_t* sectorcounts;
46 uint32_t current_chunk;
47 uint8_t *compressed_chunk;
48 uint8_t *uncompressed_chunk;
49 z_stream zstream;
50 } BDRVDMGState;
51
52 static int dmg_probe(const uint8_t *buf, int buf_size, const char *filename)
53 {
54 int len=strlen(filename);
55 if(len>4 && !strcmp(filename+len-4,".dmg"))
56 return 2;
57 return 0;
58 }
59
60 static off_t read_off(BlockDriverState *bs, int64_t offset)
61 {
62 uint64_t buffer;
63 if (bdrv_pread(bs->file, offset, &buffer, 8) < 8)
64 return 0;
65 return be64_to_cpu(buffer);
66 }
67
68 static off_t read_uint32(BlockDriverState *bs, int64_t offset)
69 {
70 uint32_t buffer;
71 if (bdrv_pread(bs->file, offset, &buffer, 4) < 4)
72 return 0;
73 return be32_to_cpu(buffer);
74 }
75
76 static int dmg_open(BlockDriverState *bs, int flags)
77 {
78 BDRVDMGState *s = bs->opaque;
79 off_t info_begin,info_end,last_in_offset,last_out_offset;
80 uint32_t count;
81 uint32_t max_compressed_size=1,max_sectors_per_chunk=1,i;
82 int64_t offset;
83
84 bs->read_only = 1;
85 s->n_chunks = 0;
86 s->offsets = s->lengths = s->sectors = s->sectorcounts = NULL;
87
88 /* read offset of info blocks */
89 offset = bdrv_getlength(bs->file);
90 if (offset < 0) {
91 goto fail;
92 }
93 offset -= 0x1d8;
94
95 info_begin = read_off(bs, offset);
96 if (info_begin == 0) {
97 goto fail;
98 }
99
100 if (read_uint32(bs, info_begin) != 0x100) {
101 goto fail;
102 }
103
104 count = read_uint32(bs, info_begin + 4);
105 if (count == 0) {
106 goto fail;
107 }
108 info_end = info_begin + count;
109
110 offset = info_begin + 0x100;
111
112 /* read offsets */
113 last_in_offset = last_out_offset = 0;
114 while (offset < info_end) {
115 uint32_t type;
116
117 count = read_uint32(bs, offset);
118 if(count==0)
119 goto fail;
120 offset += 4;
121
122 type = read_uint32(bs, offset);
123 if (type == 0x6d697368 && count >= 244) {
124 int new_size, chunk_count;
125
126 offset += 4;
127 offset += 200;
128
129 chunk_count = (count-204)/40;
130 new_size = sizeof(uint64_t) * (s->n_chunks + chunk_count);
131 s->types = g_realloc(s->types, new_size/2);
132 s->offsets = g_realloc(s->offsets, new_size);
133 s->lengths = g_realloc(s->lengths, new_size);
134 s->sectors = g_realloc(s->sectors, new_size);
135 s->sectorcounts = g_realloc(s->sectorcounts, new_size);
136
137 for(i=s->n_chunks;i<s->n_chunks+chunk_count;i++) {
138 s->types[i] = read_uint32(bs, offset);
139 offset += 4;
140 if(s->types[i]!=0x80000005 && s->types[i]!=1 && s->types[i]!=2) {
141 if(s->types[i]==0xffffffff) {
142 last_in_offset = s->offsets[i-1]+s->lengths[i-1];
143 last_out_offset = s->sectors[i-1]+s->sectorcounts[i-1];
144 }
145 chunk_count--;
146 i--;
147 offset += 36;
148 continue;
149 }
150 offset += 4;
151
152 s->sectors[i] = last_out_offset+read_off(bs, offset);
153 offset += 8;
154
155 s->sectorcounts[i] = read_off(bs, offset);
156 offset += 8;
157
158 s->offsets[i] = last_in_offset+read_off(bs, offset);
159 offset += 8;
160
161 s->lengths[i] = read_off(bs, offset);
162 offset += 8;
163
164 if(s->lengths[i]>max_compressed_size)
165 max_compressed_size = s->lengths[i];
166 if(s->sectorcounts[i]>max_sectors_per_chunk)
167 max_sectors_per_chunk = s->sectorcounts[i];
168 }
169 s->n_chunks+=chunk_count;
170 }
171 }
172
173 /* initialize zlib engine */
174 s->compressed_chunk = g_malloc(max_compressed_size+1);
175 s->uncompressed_chunk = g_malloc(512*max_sectors_per_chunk);
176 if(inflateInit(&s->zstream) != Z_OK)
177 goto fail;
178
179 s->current_chunk = s->n_chunks;
180
181 qemu_co_mutex_init(&s->lock);
182 return 0;
183 fail:
184 return -1;
185 }
186
187 static inline int is_sector_in_chunk(BDRVDMGState* s,
188 uint32_t chunk_num,int sector_num)
189 {
190 if(chunk_num>=s->n_chunks || s->sectors[chunk_num]>sector_num ||
191 s->sectors[chunk_num]+s->sectorcounts[chunk_num]<=sector_num)
192 return 0;
193 else
194 return -1;
195 }
196
197 static inline uint32_t search_chunk(BDRVDMGState* s,int sector_num)
198 {
199 /* binary search */
200 uint32_t chunk1=0,chunk2=s->n_chunks,chunk3;
201 while(chunk1!=chunk2) {
202 chunk3 = (chunk1+chunk2)/2;
203 if(s->sectors[chunk3]>sector_num)
204 chunk2 = chunk3;
205 else if(s->sectors[chunk3]+s->sectorcounts[chunk3]>sector_num)
206 return chunk3;
207 else
208 chunk1 = chunk3;
209 }
210 return s->n_chunks; /* error */
211 }
212
213 static inline int dmg_read_chunk(BlockDriverState *bs, int sector_num)
214 {
215 BDRVDMGState *s = bs->opaque;
216
217 if(!is_sector_in_chunk(s,s->current_chunk,sector_num)) {
218 int ret;
219 uint32_t chunk = search_chunk(s,sector_num);
220
221 if(chunk>=s->n_chunks)
222 return -1;
223
224 s->current_chunk = s->n_chunks;
225 switch(s->types[chunk]) {
226 case 0x80000005: { /* zlib compressed */
227 int i;
228
229 /* we need to buffer, because only the chunk as whole can be
230 * inflated. */
231 i=0;
232 do {
233 ret = bdrv_pread(bs->file, s->offsets[chunk] + i,
234 s->compressed_chunk+i, s->lengths[chunk]-i);
235 if(ret<0 && errno==EINTR)
236 ret=0;
237 i+=ret;
238 } while(ret>=0 && ret+i<s->lengths[chunk]);
239
240 if (ret != s->lengths[chunk])
241 return -1;
242
243 s->zstream.next_in = s->compressed_chunk;
244 s->zstream.avail_in = s->lengths[chunk];
245 s->zstream.next_out = s->uncompressed_chunk;
246 s->zstream.avail_out = 512*s->sectorcounts[chunk];
247 ret = inflateReset(&s->zstream);
248 if(ret != Z_OK)
249 return -1;
250 ret = inflate(&s->zstream, Z_FINISH);
251 if(ret != Z_STREAM_END || s->zstream.total_out != 512*s->sectorcounts[chunk])
252 return -1;
253 break; }
254 case 1: /* copy */
255 ret = bdrv_pread(bs->file, s->offsets[chunk],
256 s->uncompressed_chunk, s->lengths[chunk]);
257 if (ret != s->lengths[chunk])
258 return -1;
259 break;
260 case 2: /* zero */
261 memset(s->uncompressed_chunk, 0, 512*s->sectorcounts[chunk]);
262 break;
263 }
264 s->current_chunk = chunk;
265 }
266 return 0;
267 }
268
269 static int dmg_read(BlockDriverState *bs, int64_t sector_num,
270 uint8_t *buf, int nb_sectors)
271 {
272 BDRVDMGState *s = bs->opaque;
273 int i;
274
275 for(i=0;i<nb_sectors;i++) {
276 uint32_t sector_offset_in_chunk;
277 if(dmg_read_chunk(bs, sector_num+i) != 0)
278 return -1;
279 sector_offset_in_chunk = sector_num+i-s->sectors[s->current_chunk];
280 memcpy(buf+i*512,s->uncompressed_chunk+sector_offset_in_chunk*512,512);
281 }
282 return 0;
283 }
284
285 static coroutine_fn int dmg_co_read(BlockDriverState *bs, int64_t sector_num,
286 uint8_t *buf, int nb_sectors)
287 {
288 int ret;
289 BDRVDMGState *s = bs->opaque;
290 qemu_co_mutex_lock(&s->lock);
291 ret = dmg_read(bs, sector_num, buf, nb_sectors);
292 qemu_co_mutex_unlock(&s->lock);
293 return ret;
294 }
295
296 static void dmg_close(BlockDriverState *bs)
297 {
298 BDRVDMGState *s = bs->opaque;
299 if(s->n_chunks>0) {
300 free(s->types);
301 free(s->offsets);
302 free(s->lengths);
303 free(s->sectors);
304 free(s->sectorcounts);
305 }
306 free(s->compressed_chunk);
307 free(s->uncompressed_chunk);
308 inflateEnd(&s->zstream);
309 }
310
311 static BlockDriver bdrv_dmg = {
312 .format_name = "dmg",
313 .instance_size = sizeof(BDRVDMGState),
314 .bdrv_probe = dmg_probe,
315 .bdrv_open = dmg_open,
316 .bdrv_read = dmg_co_read,
317 .bdrv_close = dmg_close,
318 };
319
320 static void bdrv_dmg_init(void)
321 {
322 bdrv_register(&bdrv_dmg);
323 }
324
325 block_init(bdrv_dmg_init);