jianfeng | e00bc4e | 2012-06-19 19:53:15 +0800 | [diff] [blame] | 1 | /* |
| 2 | *Copyright (c) 2012, The Linux Foundation. All rights reserved. |
| 3 | *Redistribution and use in source and binary forms, with or without |
| 4 | *modification, are permitted provided that the following conditions are |
| 5 | *met: |
| 6 | * Redistributions of source code must retain the above copyright |
| 7 | notice, this list of conditions and the following disclaimer. |
| 8 | * Redistributions in binary form must reproduce the above |
| 9 | copyright notice, this list of conditions and the following |
| 10 | disclaimer in the documentation and/or other materials provided |
| 11 | with the distribution. |
| 12 | * Neither the name of The Linux Foundation nor the names of its |
| 13 | contributors may be used to endorse or promote products derived |
| 14 | from this software without specific prior written permission. |
| 15 | |
| 16 | *THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED |
| 17 | *WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF |
| 18 | *MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT |
| 19 | *ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS |
| 20 | *BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| 21 | *CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| 22 | *SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR |
| 23 | *BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, |
| 24 | *WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE |
| 25 | *OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN |
| 26 | *IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE |
| 27 | */ |
| 28 | #include <string.h> |
| 29 | #include "dosfs.h" |
| 30 | #include "ext.h" |
| 31 | #include "fatcache.h" |
| 32 | #include "fsutil.h" |
| 33 | #include <stdio.h> |
| 34 | #include <unistd.h> |
| 35 | #include "tree.h" |
| 36 | int fsck_msdos_cache_compare(struct cluster_chain_descriptor *fat1,struct cluster_chain_descriptor *fat2) |
| 37 | { |
| 38 | if(fat1->head > fat2->head) |
| 39 | return 1; |
| 40 | else if(fat1->head < fat2->head) |
| 41 | return -1; |
| 42 | else |
| 43 | return 0; |
| 44 | } |
| 45 | struct FSCK_MSDOS_CACHE rb_root; |
| 46 | RB_GENERATE(FSCK_MSDOS_CACHE,cluster_chain_descriptor,rb,fsck_msdos_cache_compare); |
rockiec | 0e0350a | 2013-05-16 09:24:26 -0700 | [diff] [blame] | 47 | |
| 48 | /* |
| 49 | *Function GetNextClusFromFAT |
| 50 | *PURPUSE: reconvert cluster fat from FAT table in memory |
| 51 | *PARAMETERS: |
| 52 | * boot -> pointer to the boot sector of FAT |
| 53 | * fatable -> pointer to the FAT table in memory |
| 54 | * clust ->get the next cluster of paramter clust |
| 55 | */ |
jianfeng | e00bc4e | 2012-06-19 19:53:15 +0800 | [diff] [blame] | 56 | unsigned int GetNextClusFromFAT( struct bootblock*boot,u_char*fatable,unsigned int clust) |
| 57 | { |
| 58 | unsigned int nextclus; |
| 59 | if(!fatable){ |
| 60 | fsck_err("%s:No FAT table \n",__func__); |
| 61 | return 0; |
| 62 | } |
| 63 | switch(boot->ClustMask){ |
| 64 | case CLUST32_MASK: |
| 65 | nextclus = fatable[4*clust] + (fatable[4*clust+1]<<8) + (fatable[4*clust+2]<<16) + (fatable[4*clust+3]<<24); |
| 66 | nextclus &= boot->ClustMask; |
| 67 | break; |
| 68 | |
| 69 | case CLUST16_MASK: |
| 70 | nextclus = fatable[2*clust] + (fatable[2*clust+1]<<8); |
| 71 | nextclus &= boot->ClustMask; |
| 72 | break; |
| 73 | |
| 74 | default: |
| 75 | if(clust & 0x1) |
| 76 | nextclus = ((fatable[3*(clust/2)+1]>>4) + (fatable[3*(clust/2)+2]<<4)) & 0x0fff; |
| 77 | else |
| 78 | nextclus = (fatable[3*(clust/2)] + (fatable[3*(clust/2)+1]<<8)) & 0x0fff; |
| 79 | break; |
| 80 | } |
| 81 | return nextclus; |
| 82 | } |
| 83 | |
rockiec | 0e0350a | 2013-05-16 09:24:26 -0700 | [diff] [blame] | 84 | /* |
| 85 | *Function SetNextClusToFAT |
| 86 | *PURPUSE: reconvert FAT table from cluster fats when write modified FAT table to media |
| 87 | *PARAMETERS: |
| 88 | * boot -> pointer to the boot sector of FAT |
| 89 | * fat -> pointer to the FAT table in memory |
| 90 | * cl ->set the next cluster of paramter cl |
| 91 | * next -> the next cluster of cl |
| 92 | */ |
jianfeng | e00bc4e | 2012-06-19 19:53:15 +0800 | [diff] [blame] | 93 | void SetNextClusToFAT(struct bootblock*boot,u_char*fat ,unsigned int cl ,unsigned int next) |
| 94 | { |
| 95 | /*fat must point to the head of FAT*/ |
| 96 | u_char* p; |
| 97 | if(!fat){ |
| 98 | fsck_err("%s :No FAT table \n",__func__); |
| 99 | return ; |
| 100 | } |
| 101 | switch(boot->ClustMask){ |
| 102 | case CLUST32_MASK: |
| 103 | p = fat + 4*cl; |
| 104 | *p++ = (u_char)next; |
| 105 | *p++ = (u_char)(next >>8); |
| 106 | *p++ = (u_char)(next >> 16); |
| 107 | *p &= 0xf0; |
xiaogang | 5c205e1 | 2013-01-31 18:27:23 +0800 | [diff] [blame^] | 108 | *p |= (next >> 24) & 0x0f; |
jianfeng | e00bc4e | 2012-06-19 19:53:15 +0800 | [diff] [blame] | 109 | break; |
| 110 | |
| 111 | case CLUST16_MASK: |
| 112 | p = fat + 2*cl; |
| 113 | *p++ = (u_char)next; |
| 114 | *p = (u_char)(next >> 8); |
| 115 | break; |
| 116 | |
| 117 | default: |
| 118 | p = fat + 3*(cl/2); |
| 119 | if(cl & 0x1){ |
| 120 | p++; |
| 121 | *p++ |= (u_char)(next << 4); |
| 122 | *p = (u_char)(next >> 4); |
| 123 | }else{ |
| 124 | *p++ = (u_char)next; |
| 125 | *p |= (next >> 8) & 0x0f; |
| 126 | } |
| 127 | break; |
| 128 | |
| 129 | } |
| 130 | } |
rockiec | 0e0350a | 2013-05-16 09:24:26 -0700 | [diff] [blame] | 131 | /* |
| 132 | *Function Dump_fatentry |
| 133 | *PURPUSE: dump cluster fat information for debug |
| 134 | *PARAMETERS: |
| 135 | * fat -> pointer to a cluster fat descripor |
jianfeng | e00bc4e | 2012-06-19 19:53:15 +0800 | [diff] [blame] | 136 | */ |
| 137 | void Dump_fatentry(struct cluster_chain_descriptor *fat) |
| 138 | { |
| 139 | struct fatcache *cache; |
| 140 | if(!fat){ |
| 141 | fsck_warn("%s;NULL pointer\n",__func__); |
| 142 | return ; |
| 143 | } |
| 144 | fsck_info("head: 0x%d:",fat->head); |
| 145 | cache = fat->child; |
| 146 | while(cache){ |
| 147 | fsck_info(" 0x%d:0x%d ->" ,cache->head,cache->length); |
| 148 | cache = cache->next; |
| 149 | } |
| 150 | fsck_info("EOF\n"); |
| 151 | } |
| 152 | |
rockiec | 0e0350a | 2013-05-16 09:24:26 -0700 | [diff] [blame] | 153 | /* |
| 154 | *Function add_fatcache_To_Clusterfat |
| 155 | *PURPUSE: add continuous clusters to cluster fat |
| 156 | *PARAMETERS: |
| 157 | * fatentry -> pointer to a cluster fat descripor which this fatcache be added to |
| 158 | * new -> a new fatcache which represent some continuous clusters |
| 159 | *NOTE: this function will update length in cluster_fat_descriptor |
| 160 | * pls compare this with function add_fatcache_Totail |
| 161 | */ |
jianfeng | e00bc4e | 2012-06-19 19:53:15 +0800 | [diff] [blame] | 162 | int add_fatcache_To_ClusterChain(struct cluster_chain_descriptor *fatentry ,struct fatcache *new) |
| 163 | { |
| 164 | struct fatcache *cache = fatentry->child; |
| 165 | if(!fatentry || !new){ |
| 166 | fsck_warn("%s:NULL pointer\n",__func__); |
| 167 | return -1; |
| 168 | } |
| 169 | /*NULL*/ |
| 170 | if(!cache){ |
| 171 | fatentry->child = new; |
| 172 | new->next = NULL; |
| 173 | fatentry->head = new->head; |
| 174 | fatentry->length = new->length; |
| 175 | return 0; |
| 176 | } |
| 177 | /*DO NOT sort,just add to the tail*/ |
| 178 | while(cache->next){ |
| 179 | cache = cache->next; |
| 180 | } |
| 181 | cache->next = new; |
| 182 | new->next = NULL; |
| 183 | fatentry->length += new->length; |
| 184 | return 0; |
| 185 | } |
rockiec | 0e0350a | 2013-05-16 09:24:26 -0700 | [diff] [blame] | 186 | |
jianfeng | e00bc4e | 2012-06-19 19:53:15 +0800 | [diff] [blame] | 187 | /* |
rockiec | 0e0350a | 2013-05-16 09:24:26 -0700 | [diff] [blame] | 188 | *Function add_fatcache_Totail_WithOutUpdate |
| 189 | *PURPUSE: add a fatcache to the tail of another cluster_fat_descriptor,be used to merge two existing cluster fat |
| 190 | *PARAMETERS: |
| 191 | * fatentry -> pointer to a cluster fat descripor which this fatcache be added to |
| 192 | * new -> a new fatcache which represent some continuous clusters |
| 193 | *NOTE: this function will NOT update length in cluster_fat_descriptor |
| 194 | * pls compare this with function add_fatcache_To_Clusterfat |
jianfeng | e00bc4e | 2012-06-19 19:53:15 +0800 | [diff] [blame] | 195 | */ |
| 196 | int add_fatcache_Totail(struct cluster_chain_descriptor *fatentry ,struct fatcache *new) |
| 197 | { |
| 198 | struct fatcache *cache; |
| 199 | if(!fatentry || !new || !fatentry->child){ |
| 200 | fsck_warn("%s:NULL pointer\n",__func__); |
| 201 | return -1; |
| 202 | } |
| 203 | cache = fatentry->child; |
| 204 | while(cache->next){ |
| 205 | cache = cache->next; |
| 206 | } |
| 207 | cache->next = new; |
| 208 | return 0; |
| 209 | } |
rockiec | 0e0350a | 2013-05-16 09:24:26 -0700 | [diff] [blame] | 210 | |
| 211 | /* |
| 212 | *Function Find_cache |
| 213 | *PURPUSE: find a fatcache from cluster_fat_descriptor by cluster number cl |
| 214 | *PARAMETERS: |
| 215 | * fat -> pointer to a cluster fat descripor |
| 216 | * cl -> cluster number |
| 217 | * prev_cache-> the prev fatcache of OUTPUT |
| 218 | *OUTPUT: |
| 219 | * return a fatcache which contain cluster cl |
jianfeng | e00bc4e | 2012-06-19 19:53:15 +0800 | [diff] [blame] | 220 | *NOTE: |
rockiec | 0e0350a | 2013-05-16 09:24:26 -0700 | [diff] [blame] | 221 | * if *prev_cache = return cache,that means the cache we find in cluster fat is the first one |
jianfeng | e00bc4e | 2012-06-19 19:53:15 +0800 | [diff] [blame] | 222 | */ |
| 223 | struct fatcache *Find_cache(struct cluster_chain_descriptor *fat,unsigned int cl ,struct fatcache**prev_cache) |
| 224 | { |
| 225 | struct fatcache *cache = fat->child,*prev; |
| 226 | prev = cache; |
| 227 | while(cache){ |
| 228 | if( cl >= cache->head && cl < (cache->head + cache->length)){ |
| 229 | *prev_cache = prev; |
| 230 | return cache; |
| 231 | } |
| 232 | prev = cache; |
| 233 | cache = cache->next; |
| 234 | } |
| 235 | return EMPTY_CACHE; |
| 236 | } |
| 237 | |
| 238 | /* |
rockiec | 0e0350a | 2013-05-16 09:24:26 -0700 | [diff] [blame] | 239 | *Function Find_nextclus |
| 240 | *PURPUSE: find the next cluster number of clus |
| 241 | *PARAMETERS: |
| 242 | * fat -> pointer to a cluster fat descripor |
| 243 | * clus -> find the next cluster of cluster number clus |
| 244 | * cl -> the next cluster number will returned |
| 245 | *OUTPUT: |
| 246 | * return a fatcache which contain the next cluster |
| 247 | *NOTE: |
| 248 | * if returned fatcache is null and *cl = 0 ,that means DON'T find the next cluster from the given cluster fat |
| 249 | * if returned fatcache is null but *cl != 0 ,that means clus is the last cluster of the given cluster fat |
| 250 | */ |
jianfeng | e00bc4e | 2012-06-19 19:53:15 +0800 | [diff] [blame] | 251 | struct fatcache* Find_nextclus(struct cluster_chain_descriptor* fat,unsigned int clus, unsigned int* cl) |
| 252 | { |
| 253 | struct fatcache* cache = fat->child; |
| 254 | *cl = 0x0; |
| 255 | if(!cache){ |
| 256 | fsck_warn("Not find the cluster after cluster %d\n",clus); |
| 257 | return (struct fatcache*)0; |
| 258 | } |
rockiec | a232cba | 2013-01-12 13:13:23 +0800 | [diff] [blame] | 259 | |
jianfeng | e00bc4e | 2012-06-19 19:53:15 +0800 | [diff] [blame] | 260 | while(cache){ |
| 261 | if(clus >= cache->head && clus <= cache->head + cache->length -2 ){ |
| 262 | *cl = clus + 1; |
| 263 | return cache; |
| 264 | } |
| 265 | if(clus == cache->head + cache->length -1 ){ |
| 266 | cache = cache->next; |
| 267 | if(cache){ |
| 268 | *cl = cache->head; |
| 269 | return cache; |
| 270 | }else{ |
| 271 | *cl = CLUST_EOF; |
| 272 | return (struct fatcache*)0; |
| 273 | } |
| 274 | } |
| 275 | cache = cache->next; |
| 276 | } |
| 277 | return EMPTY_CACHE; |
| 278 | } |
rockiec | 0e0350a | 2013-05-16 09:24:26 -0700 | [diff] [blame] | 279 | |
| 280 | /* |
| 281 | *Function delete_fatcache_below |
| 282 | *PURPUSE: delete all the fatcache below a given fatcache in a given cluster fat |
| 283 | *PARAMETERS: |
| 284 | * fatentry -> pointer to a cluster fat descripor |
| 285 | * cache -> the fatcache whose below fatcache will be removed |
| 286 | */ |
jianfeng | e00bc4e | 2012-06-19 19:53:15 +0800 | [diff] [blame] | 287 | int delete_fatcache_below(struct cluster_chain_descriptor * fatentry,struct fatcache*cache) |
| 288 | { |
| 289 | struct fatcache *curr = cache,*next,*last; |
| 290 | last = cache; |
| 291 | if(!cache || !fatentry){ |
| 292 | fsck_warn("%s:NULL pointer\n",__func__); |
| 293 | return -1; |
| 294 | } |
| 295 | next = curr->next; |
| 296 | if(!next) |
| 297 | return 0; |
| 298 | while(next){ |
| 299 | curr = next; |
| 300 | next = next->next; |
| 301 | fatentry->length -= curr->length; |
| 302 | free((void*)curr); |
| 303 | } |
| 304 | last->next = NULL; |
| 305 | return 0; |
| 306 | } |
| 307 | |
rockiec | 0e0350a | 2013-05-16 09:24:26 -0700 | [diff] [blame] | 308 | /* |
| 309 | *Function Trunc |
| 310 | *PURPUSE: delete all the clusters after cl from a given cluster fat |
| 311 | *PARAMETERS: |
| 312 | * fat -> pointer to a cluster fat descripor |
| 313 | * cl -> the cluster whose below clusters will be removed |
| 314 | *NOTE: this function was used to handle the issue when a file has incorrect cluster numbers |
| 315 | */ |
jianfeng | e00bc4e | 2012-06-19 19:53:15 +0800 | [diff] [blame] | 316 | void Trunc(struct cluster_chain_descriptor *fat, unsigned int cl) |
| 317 | { |
| 318 | fsck_info("fat :%p ,cl : %d \n",fat,cl); |
| 319 | struct fatcache*prev ; |
| 320 | struct fatcache*cache = Find_cache(fat,cl,&prev); |
| 321 | if(!cache) |
| 322 | return ; |
| 323 | delete_fatcache_below(fat,cache); |
| 324 | cache->length = cl - cache->head + 1; |
| 325 | fat->length -= (cache->length - (cl - cache->head) - 1); |
| 326 | } |
| 327 | |
| 328 | struct cluster_chain_descriptor* New_fatentry(void) |
| 329 | { |
| 330 | struct cluster_chain_descriptor *fat; |
| 331 | fat = calloc(1,sizeof(struct cluster_chain_descriptor)); |
| 332 | if(!fat){ |
| 333 | fsck_warn("No space\n"); |
| 334 | return fat; |
| 335 | } |
| 336 | RB_SET(fat, NULL, rb); |
| 337 | return fat; |
| 338 | } |
| 339 | |
| 340 | struct fatcache* New_fatcache(void) |
| 341 | { |
| 342 | struct fatcache *cache; |
| 343 | cache = calloc(1,sizeof(struct fatcache)); |
| 344 | if(!cache) |
| 345 | fsck_warn("No space \n"); |
| 346 | return cache; |
| 347 | } |
| 348 | |
| 349 | void free_rb_tree(void) |
| 350 | { |
| 351 | struct cluster_chain_descriptor *fat ,*next_fat; |
| 352 | struct fatcache *cache ,*next_cache; |
| 353 | fsck_info("%s \n",__func__); |
| 354 | fat = RB_MIN(FSCK_MSDOS_CACHE,&rb_root); |
| 355 | if(!fat){ |
| 356 | fsck_info("%s :rb tree is empty\n",__func__); |
| 357 | return ; |
| 358 | } |
| 359 | while(fat){ |
| 360 | cache = fat->child; |
| 361 | if(!cache) |
| 362 | continue; |
| 363 | while(cache->next){ |
| 364 | next_cache = cache->next; |
| 365 | free(cache); |
| 366 | cache = next_cache; |
| 367 | } |
| 368 | next_fat = RB_NEXT(FSCK_MSDOS_CACHE,0,fat); |
| 369 | /*must remove from rb tree before free*/ |
| 370 | RB_REMOVE(FSCK_MSDOS_CACHE,&rb_root,fat); |
| 371 | free(fat); |
| 372 | fat = next_fat; |
| 373 | } |
| 374 | } |