1 /* 2 * dblist.c -- directory block list functions 3 * 4 * Copyright 1997 by Theodore Ts'o 5 * 6 * %Begin-Header% 7 * This file may be redistributed under the terms of the GNU Library 8 * General Public License, version 2. 9 * %End-Header% 10 */ 11 12 #include <stdio.h> 13 #if HAVE_UNISTD_H 14 #include <unistd.h> 15 #endif 16 #include <string.h> 17 #include <time.h> 18 19 #include "ext2_fs.h" 20 #include "ext2fsP.h" 21 22 static EXT2_QSORT_TYPE dir_block_cmp(const void *a, const void *b); 23 static EXT2_QSORT_TYPE dir_block_cmp2(const void *a, const void *b); 24 static EXT2_QSORT_TYPE (*sortfunc32)(const void *a, const void *b); 25 26 /* 27 * Returns the number of directories in the filesystem as reported by 28 * the group descriptors. Of course, the group descriptors could be 29 * wrong! 30 */ 31 errcode_t ext2fs_get_num_dirs(ext2_filsys fs, ext2_ino_t *ret_num_dirs) 32 { 33 dgrp_t i; 34 ext2_ino_t num_dirs, max_dirs; 35 36 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); 37 38 num_dirs = 0; 39 max_dirs = fs->super->s_inodes_per_group; 40 for (i = 0; i < fs->group_desc_count; i++) { 41 if (ext2fs_bg_used_dirs_count(fs, i) > max_dirs) 42 num_dirs += max_dirs / 8; 43 else 44 num_dirs += ext2fs_bg_used_dirs_count(fs, i); 45 } 46 if (num_dirs > fs->super->s_inodes_count) 47 num_dirs = fs->super->s_inodes_count; 48 49 *ret_num_dirs = num_dirs; 50 51 return 0; 52 } 53 54 /* 55 * helper function for making a new directory block list (for 56 * initialize and copy). 57 */ 58 static errcode_t make_dblist(ext2_filsys fs, ext2_ino_t size, 59 ext2_ino_t count, 60 struct ext2_db_entry2 *list, 61 ext2_dblist *ret_dblist) 62 { 63 ext2_dblist dblist = NULL; 64 errcode_t retval; 65 ext2_ino_t num_dirs; 66 size_t len; 67 68 EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); 69 70 if ((ret_dblist == 0) && fs->dblist && 71 (fs->dblist->magic == EXT2_ET_MAGIC_DBLIST)) 72 return 0; 73 74 retval = ext2fs_get_mem(sizeof(struct ext2_struct_dblist), &dblist); 75 if (retval) 76 goto cleanup; 77 memset(dblist, 0, sizeof(struct ext2_struct_dblist)); 78 79 dblist->magic = EXT2_ET_MAGIC_DBLIST; 80 dblist->fs = fs; 81 if (size) 82 dblist->size = size; 83 else { 84 retval = ext2fs_get_num_dirs(fs, &num_dirs); 85 if (retval) 86 goto cleanup; 87 dblist->size = (num_dirs * 2) + 12; 88 } 89 len = (size_t) sizeof(struct ext2_db_entry2) * dblist->size; 90 dblist->count = count; 91 retval = ext2fs_get_array(dblist->size, sizeof(struct ext2_db_entry2), 92 &dblist->list); 93 if (retval) 94 goto cleanup; 95 96 if (list) 97 memcpy(dblist->list, list, len); 98 else 99 memset(dblist->list, 0, len); 100 if (ret_dblist) 101 *ret_dblist = dblist; 102 else 103 fs->dblist = dblist; 104 return 0; 105 cleanup: 106 if (dblist) 107 ext2fs_free_mem(&dblist); 108 return retval; 109 } 110 111 /* 112 * Initialize a directory block list 113 */ 114 errcode_t ext2fs_init_dblist(ext2_filsys fs, ext2_dblist *ret_dblist) 115 { 116 ext2_dblist dblist; 117 errcode_t retval; 118 119 retval = make_dblist(fs, 0, 0, 0, &dblist); 120 if (retval) 121 return retval; 122 123 dblist->sorted = 1; 124 if (ret_dblist) 125 *ret_dblist = dblist; 126 else 127 fs->dblist = dblist; 128 129 return 0; 130 } 131 132 /* 133 * Copy a directory block list 134 */ 135 errcode_t ext2fs_copy_dblist(ext2_dblist src, ext2_dblist *dest) 136 { 137 ext2_dblist dblist; 138 errcode_t retval; 139 140 retval = make_dblist(src->fs, src->size, src->count, src->list, 141 &dblist); 142 if (retval) 143 return retval; 144 dblist->sorted = src->sorted; 145 *dest = dblist; 146 return 0; 147 } 148 149 /* 150 * Close a directory block list 151 * 152 * (moved to closefs.c) 153 */ 154 155 156 /* 157 * Add a directory block to the directory block list 158 */ 159 errcode_t ext2fs_add_dir_block2(ext2_dblist dblist, ext2_ino_t ino, 160 blk64_t blk, e2_blkcnt_t blockcnt) 161 { 162 struct ext2_db_entry2 *new_entry; 163 errcode_t retval; 164 unsigned long old_size; 165 166 EXT2_CHECK_MAGIC(dblist, EXT2_ET_MAGIC_DBLIST); 167 168 if (dblist->count >= dblist->size) { 169 old_size = dblist->size * sizeof(struct ext2_db_entry2); 170 dblist->size += dblist->size > 200 ? dblist->size / 2 : 100; 171 retval = ext2fs_resize_mem(old_size, (size_t) dblist->size * 172 sizeof(struct ext2_db_entry2), 173 &dblist->list); 174 if (retval) { 175 dblist->size = old_size / sizeof(struct ext2_db_entry2); 176 return retval; 177 } 178 } 179 new_entry = dblist->list + ( dblist->count++); 180 new_entry->blk = blk; 181 new_entry->ino = ino; 182 new_entry->blockcnt = blockcnt; 183 184 dblist->sorted = 0; 185 186 return 0; 187 } 188 189 /* 190 * Change the directory block to the directory block list 191 */ 192 errcode_t ext2fs_set_dir_block2(ext2_dblist dblist, ext2_ino_t ino, 193 blk64_t blk, e2_blkcnt_t blockcnt) 194 { 195 dgrp_t i; 196 197 EXT2_CHECK_MAGIC(dblist, EXT2_ET_MAGIC_DBLIST); 198 199 for (i=0; i < dblist->count; i++) { 200 if ((dblist->list[i].ino != ino) || 201 (dblist->list[i].blockcnt != blockcnt)) 202 continue; 203 dblist->list[i].blk = blk; 204 dblist->sorted = 0; 205 return 0; 206 } 207 return EXT2_ET_DB_NOT_FOUND; 208 } 209 210 void ext2fs_dblist_sort2(ext2_dblist dblist, 211 EXT2_QSORT_TYPE (*sortfunc)(const void *, 212 const void *)) 213 { 214 if (!sortfunc) 215 sortfunc = dir_block_cmp2; 216 qsort(dblist->list, (size_t) dblist->count, 217 sizeof(struct ext2_db_entry2), sortfunc); 218 dblist->sorted = 1; 219 } 220 221 /* 222 * This function iterates over the directory block list 223 */ 224 errcode_t ext2fs_dblist_iterate2(ext2_dblist dblist, 225 int (*func)(ext2_filsys fs, 226 struct ext2_db_entry2 *db_info, 227 void *priv_data), 228 void *priv_data) 229 { 230 unsigned long long i; 231 int ret; 232 233 EXT2_CHECK_MAGIC(dblist, EXT2_ET_MAGIC_DBLIST); 234 235 if (!dblist->sorted) 236 ext2fs_dblist_sort2(dblist, 0); 237 for (i=0; i < dblist->count; i++) { 238 ret = (*func)(dblist->fs, &dblist->list[i], priv_data); 239 if (ret & DBLIST_ABORT) 240 return 0; 241 } 242 return 0; 243 } 244 245 static EXT2_QSORT_TYPE dir_block_cmp2(const void *a, const void *b) 246 { 247 const struct ext2_db_entry2 *db_a = 248 (const struct ext2_db_entry2 *) a; 249 const struct ext2_db_entry2 *db_b = 250 (const struct ext2_db_entry2 *) b; 251 252 if (db_a->blk != db_b->blk) 253 return (int) (db_a->blk - db_b->blk); 254 255 if (db_a->ino != db_b->ino) 256 return (int) (db_a->ino - db_b->ino); 257 258 return (db_a->blockcnt - db_b->blockcnt); 259 } 260 261 blk64_t ext2fs_dblist_count2(ext2_dblist dblist) 262 { 263 return dblist->count; 264 } 265 266 errcode_t ext2fs_dblist_get_last2(ext2_dblist dblist, 267 struct ext2_db_entry2 **entry) 268 { 269 EXT2_CHECK_MAGIC(dblist, EXT2_ET_MAGIC_DBLIST); 270 271 if (dblist->count == 0) 272 return EXT2_ET_DBLIST_EMPTY; 273 274 if (entry) 275 *entry = dblist->list + ( dblist->count-1); 276 return 0; 277 } 278 279 errcode_t ext2fs_dblist_drop_last(ext2_dblist dblist) 280 { 281 EXT2_CHECK_MAGIC(dblist, EXT2_ET_MAGIC_DBLIST); 282 283 if (dblist->count == 0) 284 return EXT2_ET_DBLIST_EMPTY; 285 286 dblist->count--; 287 return 0; 288 } 289 290 /* 291 * Legacy 32-bit versions 292 */ 293 294 /* 295 * Add a directory block to the directory block list 296 */ 297 errcode_t ext2fs_add_dir_block(ext2_dblist dblist, ext2_ino_t ino, blk_t blk, 298 int blockcnt) 299 { 300 return ext2fs_add_dir_block2(dblist, ino, blk, blockcnt); 301 } 302 303 /* 304 * Change the directory block to the directory block list 305 */ 306 errcode_t ext2fs_set_dir_block(ext2_dblist dblist, ext2_ino_t ino, blk_t blk, 307 int blockcnt) 308 { 309 return ext2fs_set_dir_block2(dblist, ino, blk, blockcnt); 310 } 311 312 void ext2fs_dblist_sort(ext2_dblist dblist, 313 EXT2_QSORT_TYPE (*sortfunc)(const void *, 314 const void *)) 315 { 316 if (sortfunc) { 317 sortfunc32 = sortfunc; 318 sortfunc = dir_block_cmp; 319 } else 320 sortfunc = dir_block_cmp2; 321 qsort(dblist->list, (size_t) dblist->count, 322 sizeof(struct ext2_db_entry2), sortfunc); 323 dblist->sorted = 1; 324 } 325 326 /* 327 * This function iterates over the directory block list 328 */ 329 struct iterate_passthrough { 330 int (*func)(ext2_filsys fs, 331 struct ext2_db_entry *db_info, 332 void *priv_data); 333 void *priv_data; 334 }; 335 336 static int passthrough_func(ext2_filsys fs, 337 struct ext2_db_entry2 *db_info, 338 void *priv_data) 339 { 340 struct iterate_passthrough *p = priv_data; 341 struct ext2_db_entry db; 342 int ret; 343 344 db.ino = db_info->ino; 345 db.blk = (blk_t) db_info->blk; 346 db.blockcnt = (int) db_info->blockcnt; 347 ret = (p->func)(fs, &db, p->priv_data); 348 db_info->ino = db.ino; 349 db_info->blk = db.blk; 350 db_info->blockcnt = db.blockcnt; 351 return ret; 352 } 353 354 errcode_t ext2fs_dblist_iterate(ext2_dblist dblist, 355 int (*func)(ext2_filsys fs, 356 struct ext2_db_entry *db_info, 357 void *priv_data), 358 void *priv_data) 359 { 360 struct iterate_passthrough pass; 361 362 EXT2_CHECK_MAGIC(dblist, EXT2_ET_MAGIC_DBLIST); 363 pass.func = func; 364 pass.priv_data = priv_data; 365 366 return ext2fs_dblist_iterate2(dblist, passthrough_func, &pass); 367 } 368 369 static EXT2_QSORT_TYPE dir_block_cmp(const void *a, const void *b) 370 { 371 const struct ext2_db_entry2 *db_a = 372 (const struct ext2_db_entry2 *) a; 373 const struct ext2_db_entry2 *db_b = 374 (const struct ext2_db_entry2 *) b; 375 376 struct ext2_db_entry a32, b32; 377 378 a32.ino = db_a->ino; a32.blk = db_a->blk; 379 a32.blockcnt = db_a->blockcnt; 380 381 b32.ino = db_b->ino; b32.blk = db_b->blk; 382 b32.blockcnt = db_b->blockcnt; 383 384 return sortfunc32(&a32, &b32); 385 } 386 387 int ext2fs_dblist_count(ext2_dblist dblist) 388 { 389 return dblist->count; 390 } 391 392 errcode_t ext2fs_dblist_get_last(ext2_dblist dblist, 393 struct ext2_db_entry **entry) 394 { 395 static struct ext2_db_entry ret_entry; 396 struct ext2_db_entry2 *last; 397 398 EXT2_CHECK_MAGIC(dblist, EXT2_ET_MAGIC_DBLIST); 399 400 if (dblist->count == 0) 401 return EXT2_ET_DBLIST_EMPTY; 402 403 if (!entry) 404 return 0; 405 406 last = dblist->list + dblist->count -1; 407 408 ret_entry.ino = last->ino; 409 ret_entry.blk = last->blk; 410 ret_entry.blockcnt = last->blockcnt; 411 *entry = &ret_entry; 412 413 return 0; 414 } 415 416
