| File: | ext2fs/dir.c |
| Location: | line 195, column 3 |
| Description: | Value stored to 'err' is never read |
| 1 | /* Directory management routines |
| 2 | |
| 3 | Copyright (C) 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2007 |
| 4 | Free Software Foundation, Inc. |
| 5 | |
| 6 | Converted for ext2fs by Miles Bader <miles@gnu.org> |
| 7 | |
| 8 | This program is free software; you can redistribute it and/or |
| 9 | modify it under the terms of the GNU General Public License as |
| 10 | published by the Free Software Foundation; either version 2, or (at |
| 11 | your option) any later version. |
| 12 | |
| 13 | This program is distributed in the hope that it will be useful, but |
| 14 | WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 16 | General Public License for more details. |
| 17 | |
| 18 | You should have received a copy of the GNU General Public License |
| 19 | along with this program; if not, write to the Free Software |
| 20 | Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ |
| 21 | |
| 22 | #include "ext2fs.h" |
| 23 | |
| 24 | #include <string.h> |
| 25 | #include <stdio.h> |
| 26 | #include <dirent.h> |
| 27 | #include <stddef.h> |
| 28 | |
| 29 | /* This isn't quite right because a file system block may straddle several |
| 30 | device blocks, and so a write failure between writing two device blocks |
| 31 | may scramble things up a bit. But the linux doesn't do this. We could |
| 32 | try and make sure that we never wrote any modified directories with |
| 33 | entries that straddle device blocks (but read those that do)... */ |
| 34 | #define DIRBLKSIZblock_size block_size |
| 35 | |
| 36 | enum slot_status |
| 37 | { |
| 38 | /* This means we haven't yet found room for a new entry. */ |
| 39 | LOOKING, |
| 40 | |
| 41 | /* This means that the specified entry is free and should be used. */ |
| 42 | TAKE, |
| 43 | |
| 44 | /* This means that the specified entry has enough room at the end |
| 45 | to hold the new entry. */ |
| 46 | SHRINK, |
| 47 | |
| 48 | /* This means that there is enough space in the block, but not in |
| 49 | any one single entry, so they all have to be shifted to make |
| 50 | room. */ |
| 51 | COMPRESS, |
| 52 | |
| 53 | /* This means that the directory will have to be grown to hold the |
| 54 | entry. */ |
| 55 | EXTEND, |
| 56 | |
| 57 | /* For removal and rename, this means that this is the location |
| 58 | of the entry found. */ |
| 59 | HERE_TIS, |
| 60 | }; |
| 61 | |
| 62 | struct dirstat |
| 63 | { |
| 64 | /* Type of followp operation expected */ |
| 65 | enum lookup_type type; |
| 66 | |
| 67 | /* One of the statuses above */ |
| 68 | enum slot_status stat; |
| 69 | |
| 70 | /* Mapped address and length of directory */ |
| 71 | vm_address_t mapbuf; |
| 72 | vm_size_t mapextent; |
| 73 | |
| 74 | /* Index of this directory block. */ |
| 75 | int idx; |
| 76 | |
| 77 | /* For stat COMPRESS, this is the address (inside mapbuf) |
| 78 | of the first direct in the directory block to be compressed. */ |
| 79 | /* For stat HERE_TIS, SHRINK, and TAKE, this is the entry referenced. */ |
| 80 | struct ext2_dir_entry_2 *entry; |
| 81 | |
| 82 | /* For stat HERE_TIS, type REMOVE, this is the address of the immediately |
| 83 | previous direct in this directory block, or zero if this is the first. */ |
| 84 | struct ext2_dir_entry_2 *preventry; |
| 85 | |
| 86 | /* For stat COMPRESS, this is the number of bytes needed to be copied |
| 87 | in order to undertake the compression. */ |
| 88 | size_t nbytes; |
| 89 | }; |
| 90 | |
| 91 | const size_t diskfs_dirstat_size = sizeof (struct dirstat); |
| 92 | |
| 93 | /* Initialize DS such that diskfs_drop_dirstat will ignore it. */ |
| 94 | void |
| 95 | diskfs_null_dirstat (struct dirstat *ds) |
| 96 | { |
| 97 | ds->type = LOOKUP; |
| 98 | } |
| 99 | |
| 100 | static error_t |
| 101 | dirscanblock (vm_address_t blockoff, struct node *dp, int idx, |
| 102 | const char *name, int namelen, enum lookup_type type, |
| 103 | struct dirstat *ds, ino_t *inum); |
| 104 | |
| 105 | |
| 106 | #if 0 /* XXX unused for now */ |
| 107 | static const unsigned char ext2_file_type[EXT2_FT_MAX8] = |
| 108 | { |
| 109 | [EXT2_FT_UNKNOWN0] = DT_UNKNOWNDT_UNKNOWN, |
| 110 | [EXT2_FT_REG_FILE1] = DT_REGDT_REG, |
| 111 | [EXT2_FT_DIR2] = DT_DIRDT_DIR, |
| 112 | [EXT2_FT_CHRDEV3] = DT_CHRDT_CHR, |
| 113 | [EXT2_FT_BLKDEV4] = DT_BLKDT_BLK, |
| 114 | [EXT2_FT_FIFO5] = DT_FIFODT_FIFO, |
| 115 | [EXT2_FT_SOCK6] = DT_SOCKDT_SOCK, |
| 116 | [EXT2_FT_SYMLINK7] = DT_LNKDT_LNK, |
| 117 | }; |
| 118 | |
| 119 | static const unsigned char file_type_ext2[] = |
| 120 | { |
| 121 | [DT_UNKNOWNDT_UNKNOWN] = EXT2_FT_UNKNOWN0, |
| 122 | [DT_REGDT_REG] = EXT2_FT_REG_FILE1, |
| 123 | [DT_DIRDT_DIR] = EXT2_FT_DIR2, |
| 124 | [DT_CHRDT_CHR] = EXT2_FT_CHRDEV3, |
| 125 | [DT_BLKDT_BLK] = EXT2_FT_BLKDEV4, |
| 126 | [DT_FIFODT_FIFO] = EXT2_FT_FIFO5, |
| 127 | [DT_SOCKDT_SOCK] = EXT2_FT_SOCK6, |
| 128 | [DT_LNKDT_LNK] = EXT2_FT_SYMLINK7, |
| 129 | }; |
| 130 | #endif |
| 131 | |
| 132 | /* Implement the diskfs_lookup from the diskfs library. See |
| 133 | <hurd/diskfs.h> for the interface specification. */ |
| 134 | error_t |
| 135 | diskfs_lookup_hard (struct node *dp, const char *name, enum lookup_type type, |
| 136 | struct node **npp, struct dirstat *ds, struct protid *cred) |
| 137 | { |
| 138 | error_t err; |
| 139 | ino_t inum; |
| 140 | int namelen; |
| 141 | int spec_dotdot; |
| 142 | struct node *np = 0; |
| 143 | int retry_dotdot = 0; |
| 144 | vm_prot_t prot = |
| 145 | (type == LOOKUP) ? VM_PROT_READ((vm_prot_t) 0x01) : (VM_PROT_READ((vm_prot_t) 0x01) | VM_PROT_WRITE((vm_prot_t) 0x02)); |
| 146 | memory_object_t memobj; |
| 147 | vm_address_t buf = 0; |
| 148 | vm_size_t buflen = 0; |
| 149 | int blockaddr; |
| 150 | int idx, lastidx; |
| 151 | int looped; |
| 152 | |
| 153 | if ((type == REMOVE) || (type == RENAME)) |
| 154 | assert (npp)((npp) ? (void) (0) : __assert_fail ("npp", "dir.c", 154, __PRETTY_FUNCTION__ )); |
| 155 | |
| 156 | if (npp) |
| 157 | *npp = 0; |
| 158 | |
| 159 | spec_dotdot = type & SPEC_DOTDOT0x10000000; |
| 160 | type &= ~SPEC_DOTDOT0x10000000; |
| 161 | |
| 162 | namelen = strlen (name); |
| 163 | |
| 164 | if (namelen > EXT2_NAME_LEN255) |
| 165 | { |
| 166 | if (ds) |
| 167 | diskfs_null_dirstat (ds); |
| 168 | return ENAMETOOLONG((0x10 << 26) | ((63) & 0x3fff)); |
| 169 | } |
| 170 | |
| 171 | try_again: |
| 172 | if (ds) |
| 173 | { |
| 174 | ds->type = LOOKUP; |
| 175 | ds->mapbuf = 0; |
| 176 | ds->mapextent = 0; |
| 177 | } |
| 178 | if (buf) |
| 179 | { |
| 180 | munmap ((caddr_t) buf, buflen); |
| 181 | buf = 0; |
| 182 | } |
| 183 | if (ds && (type == CREATE || type == RENAME)) |
| 184 | ds->stat = LOOKING; |
| 185 | |
| 186 | /* Map in the directory contents. */ |
| 187 | memobj = diskfs_get_filemap (dp, prot); |
| 188 | |
| 189 | if (memobj == MACH_PORT_NULL((mach_port_t) 0)) |
| 190 | return errno(*__errno_location ()); |
| 191 | |
| 192 | buf = 0; |
| 193 | /* We allow extra space in case we have to do an EXTEND. */ |
| 194 | buflen = round_page (dp->dn_stat.st_size + DIRBLKSIZ)((((vm_offset_t) (dp->dn_stat.st_size + block_size) + __vm_page_size - 1) / __vm_page_size) * __vm_page_size); |
| 195 | err = vm_map (mach_task_self ()((__mach_task_self_ + 0)), |
Value stored to 'err' is never read | |
| 196 | &buf, buflen, 0, 1, memobj, 0, 0, prot, prot, 0); |
| 197 | mach_port_deallocate (mach_task_self ()((__mach_task_self_ + 0)), memobj); |
| 198 | |
| 199 | inum = 0; |
| 200 | |
| 201 | diskfs_set_node_atime (dp); |
| 202 | |
| 203 | /* Start the lookup at DP->dn->dir_idx. */ |
| 204 | idx = dp->dn->dir_idx; |
| 205 | if (idx * DIRBLKSIZblock_size > dp->dn_stat.st_size) |
| 206 | idx = 0; /* just in case */ |
| 207 | blockaddr = buf + idx * DIRBLKSIZblock_size; |
| 208 | looped = (idx == 0); |
| 209 | lastidx = idx; |
| 210 | if (lastidx == 0) |
| 211 | lastidx = dp->dn_stat.st_size / DIRBLKSIZblock_size; |
| 212 | |
| 213 | while (!looped || idx < lastidx) |
| 214 | { |
| 215 | err = dirscanblock (blockaddr, dp, idx, name, namelen, type, ds, &inum); |
| 216 | if (!err) |
| 217 | { |
| 218 | dp->dn->dir_idx = idx; |
| 219 | break; |
| 220 | } |
| 221 | if (err != ENOENT((0x10 << 26) | ((2) & 0x3fff))) |
| 222 | { |
| 223 | munmap ((caddr_t) buf, buflen); |
| 224 | return err; |
| 225 | } |
| 226 | |
| 227 | blockaddr += DIRBLKSIZblock_size; |
| 228 | idx++; |
| 229 | if (blockaddr - buf >= dp->dn_stat.st_size && !looped) |
| 230 | { |
| 231 | /* We've gotten to the end; start back at the beginning */ |
| 232 | looped = 1; |
| 233 | blockaddr = buf; |
| 234 | idx = 0; |
| 235 | } |
| 236 | } |
| 237 | |
| 238 | diskfs_set_node_atime (dp); |
| 239 | if (diskfs_synchronous) |
| 240 | diskfs_node_update (dp, 1); |
| 241 | |
| 242 | /* If err is set here, it's ENOENT, and we don't want to |
| 243 | think about that as an error yet. */ |
| 244 | err = 0; |
| 245 | |
| 246 | if (inum && npp) |
| 247 | { |
| 248 | if (namelen != 2 || name[0] != '.' || name[1] != '.') |
| 249 | { |
| 250 | if (inum == dp->cache_id) |
| 251 | { |
| 252 | np = dp; |
| 253 | diskfs_nref (np); |
| 254 | } |
| 255 | else |
| 256 | { |
| 257 | err = diskfs_cached_lookup (inum, &np); |
| 258 | if (err) |
| 259 | goto out; |
| 260 | } |
| 261 | } |
| 262 | |
| 263 | /* We are looking up .. */ |
| 264 | /* Check to see if this is the root of the filesystem. */ |
| 265 | else if (dp->cache_id == 2) |
| 266 | { |
| 267 | err = EAGAIN((0x10 << 26) | ((35) & 0x3fff)); |
| 268 | goto out; |
| 269 | } |
| 270 | |
| 271 | /* We can't just do diskfs_cached_lookup, because we would then deadlock. |
| 272 | So we do this. Ick. */ |
| 273 | else if (retry_dotdot) |
| 274 | { |
| 275 | /* Check to see that we got the same answer as last time. */ |
| 276 | if (inum != retry_dotdot) |
| 277 | { |
| 278 | /* Drop what we *thought* was .. (but isn't any more) and |
| 279 | try *again*. */ |
| 280 | diskfs_nput (np); |
| 281 | pthread_mutex_unlock (&dp->lock); |
| 282 | err = diskfs_cached_lookup (inum, &np); |
| 283 | pthread_mutex_lock (&dp->lock); |
| 284 | if (err) |
| 285 | goto out; |
| 286 | retry_dotdot = inum; |
| 287 | goto try_again; |
| 288 | } |
| 289 | /* Otherwise, we got it fine and np is already set properly. */ |
| 290 | } |
| 291 | else if (!spec_dotdot) |
| 292 | { |
| 293 | /* Lock them in the proper order, and then |
| 294 | repeat the directory scan to see if this is still |
| 295 | right. */ |
| 296 | pthread_mutex_unlock (&dp->lock); |
| 297 | err = diskfs_cached_lookup (inum, &np); |
| 298 | pthread_mutex_lock (&dp->lock); |
| 299 | if (err) |
| 300 | goto out; |
| 301 | retry_dotdot = inum; |
| 302 | goto try_again; |
| 303 | } |
| 304 | |
| 305 | /* Here below are the spec dotdot cases. */ |
| 306 | else if (type == RENAME || type == REMOVE) |
| 307 | np = ifind (inum); |
| 308 | |
| 309 | else if (type == LOOKUP) |
| 310 | { |
| 311 | diskfs_nput (dp); |
| 312 | err = diskfs_cached_lookup (inum, &np); |
| 313 | if (err) |
| 314 | goto out; |
| 315 | } |
| 316 | else |
| 317 | assert (0)((0) ? (void) (0) : __assert_fail ("0", "dir.c", 317, __PRETTY_FUNCTION__ )); |
| 318 | } |
| 319 | |
| 320 | if ((type == CREATE || type == RENAME) && !inum && ds && ds->stat == LOOKING) |
| 321 | { |
| 322 | /* We didn't find any room, so mark ds to extend the dir */ |
| 323 | ds->type = CREATE; |
| 324 | ds->stat = EXTEND; |
| 325 | ds->idx = dp->dn_stat.st_size / DIRBLKSIZblock_size; |
| 326 | } |
| 327 | |
| 328 | /* Return to the user; if we can't, release the reference |
| 329 | (and lock) we acquired above. */ |
| 330 | out: |
| 331 | /* Deallocate or save the mapping. */ |
| 332 | if ((err && err != ENOENT((0x10 << 26) | ((2) & 0x3fff))) |
| 333 | || !ds |
| 334 | || ds->type == LOOKUP) |
| 335 | { |
| 336 | munmap ((caddr_t) buf, buflen); |
| 337 | if (ds) |
| 338 | ds->type = LOOKUP; /* set to be ignored by drop_dirstat */ |
| 339 | } |
| 340 | else |
| 341 | { |
| 342 | ds->mapbuf = buf; |
| 343 | ds->mapextent = buflen; |
| 344 | } |
| 345 | |
| 346 | if (np) |
| 347 | { |
| 348 | assert (npp)((npp) ? (void) (0) : __assert_fail ("npp", "dir.c", 348, __PRETTY_FUNCTION__ )); |
| 349 | if (err) |
| 350 | { |
| 351 | if (!spec_dotdot) |
| 352 | { |
| 353 | /* Normal case */ |
| 354 | if (np == dp) |
| 355 | diskfs_nrele (np); |
| 356 | else |
| 357 | diskfs_nput (np); |
| 358 | } |
| 359 | else if (type == RENAME || type == REMOVE) |
| 360 | /* We just did ifind to get np; that allocates |
| 361 | no new references, so we don't have anything to do */ |
| 362 | ; |
| 363 | else if (type == LOOKUP) |
| 364 | /* We did diskfs_cached_lookup */ |
| 365 | diskfs_nput (np); |
| 366 | } |
| 367 | else |
| 368 | *npp = np; |
| 369 | } |
| 370 | |
| 371 | return err ? : inum ? 0 : ENOENT((0x10 << 26) | ((2) & 0x3fff)); |
| 372 | } |
| 373 | |
| 374 | /* Scan block at address BLKADDR (of node DP; block index IDX), for |
| 375 | name NAME of length NAMELEN. Args TYPE, DS are as for |
| 376 | diskfs_lookup. If found, set *INUM to the inode number, else |
| 377 | return ENOENT. */ |
| 378 | static error_t |
| 379 | dirscanblock (vm_address_t blockaddr, struct node *dp, int idx, |
| 380 | const char *name, int namelen, enum lookup_type type, |
| 381 | struct dirstat *ds, ino_t *inum) |
| 382 | { |
| 383 | int nfree = 0; |
| 384 | int needed = 0; |
| 385 | vm_address_t currentoff, prevoff; |
| 386 | struct ext2_dir_entry_2 *entry = 0; |
| 387 | int nentries = 0; |
| 388 | size_t nbytes = 0; |
| 389 | int looking = 0; |
| 390 | int countcopies = 0; |
| 391 | int consider_compress = 0; |
| 392 | |
| 393 | if (ds && (ds->stat == LOOKING |
| 394 | || ds->stat == COMPRESS)) |
| 395 | { |
| 396 | looking = 1; |
| 397 | countcopies = 1; |
| 398 | needed = EXT2_DIR_REC_LEN (namelen)(((namelen) + 8 + (4 - 1)) & ~(4 - 1)); |
| 399 | } |
| 400 | |
| 401 | for (currentoff = blockaddr, prevoff = 0; |
| 402 | currentoff < blockaddr + DIRBLKSIZblock_size; |
| 403 | prevoff = currentoff, currentoff += entry->rec_len) |
| 404 | { |
| 405 | entry = (struct ext2_dir_entry_2 *)currentoff; |
| 406 | |
| 407 | if (!entry->rec_len |
| 408 | || entry->rec_len % EXT2_DIR_PAD4 |
| 409 | || entry->name_len > EXT2_NAME_LEN255 |
| 410 | || currentoff + entry->rec_len > blockaddr + DIRBLKSIZblock_size |
| 411 | || EXT2_DIR_REC_LEN (entry->name_len)(((entry->name_len) + 8 + (4 - 1)) & ~(4 - 1)) > entry->rec_len |
| 412 | || memchr (entry->name, '\0', entry->name_len)) |
| 413 | { |
| 414 | ext2_warning ("bad directory entry: inode: %Ld offset: %zd", |
| 415 | dp->cache_id, |
| 416 | currentoff - blockaddr + idx * DIRBLKSIZblock_size); |
| 417 | return ENOENT((0x10 << 26) | ((2) & 0x3fff)); |
| 418 | } |
| 419 | |
| 420 | if (looking || countcopies) |
| 421 | { |
| 422 | int thisfree; |
| 423 | |
| 424 | /* Count how much free space this entry has in it. */ |
| 425 | if (entry->inode == 0) |
| 426 | thisfree = entry->rec_len; |
| 427 | else |
| 428 | thisfree = entry->rec_len - EXT2_DIR_REC_LEN (entry->name_len)(((entry->name_len) + 8 + (4 - 1)) & ~(4 - 1)); |
| 429 | |
| 430 | /* If this isn't at the front of the block, then it will |
| 431 | have to be copied if we do a compression; count the |
| 432 | number of bytes there too. */ |
| 433 | if (countcopies && currentoff != blockaddr) |
| 434 | nbytes += EXT2_DIR_REC_LEN (entry->name_len)(((entry->name_len) + 8 + (4 - 1)) & ~(4 - 1)); |
| 435 | |
| 436 | if (ds->stat == COMPRESS && nbytes > ds->nbytes) |
| 437 | /* The previously found compress is better than |
| 438 | this one, so don't bother counting any more. */ |
| 439 | countcopies = 0; |
| 440 | |
| 441 | if (thisfree >= needed) |
| 442 | { |
| 443 | ds->type = CREATE; |
| 444 | ds->stat = entry->inode == 0 ? TAKE : SHRINK; |
| 445 | ds->entry = entry; |
| 446 | ds->idx = idx; |
| 447 | looking = countcopies = 0; |
| 448 | } |
| 449 | else |
| 450 | { |
| 451 | nfree += thisfree; |
| 452 | if (nfree >= needed) |
| 453 | consider_compress = 1; |
| 454 | } |
| 455 | } |
| 456 | |
| 457 | if (entry->inode) |
| 458 | nentries++; |
| 459 | |
| 460 | if (entry->name_len == namelen |
| 461 | && entry->name[0] == name[0] |
| 462 | && entry->inode |
| 463 | && !bcmp (entry->name, name, namelen)) |
| 464 | break; |
| 465 | } |
| 466 | |
| 467 | if (consider_compress |
| 468 | && (ds->stat == LOOKING |
| 469 | || (ds->stat == COMPRESS && ds->nbytes > nbytes))) |
| 470 | { |
| 471 | ds->type = CREATE; |
| 472 | ds->stat = COMPRESS; |
| 473 | ds->entry = (struct ext2_dir_entry_2 *) blockaddr; |
| 474 | ds->idx = idx; |
| 475 | ds->nbytes = nbytes; |
| 476 | } |
| 477 | |
| 478 | if (currentoff >= blockaddr + DIRBLKSIZblock_size) |
| 479 | { |
| 480 | int i; |
| 481 | /* The name is not in this block. */ |
| 482 | |
| 483 | /* Because we scanned the entire block, we should write |
| 484 | down how many entries there were. */ |
| 485 | if (!dp->dn->dirents) |
| 486 | { |
| 487 | dp->dn->dirents = malloc ((dp->dn_stat.st_size / DIRBLKSIZblock_size) |
| 488 | * sizeof (int)); |
| 489 | for (i = 0; i < dp->dn_stat.st_size/DIRBLKSIZblock_size; i++) |
| 490 | dp->dn->dirents[i] = -1; |
| 491 | } |
| 492 | /* Make sure the count is correct if there is one now. */ |
| 493 | assert (dp->dn->dirents[idx] == -1((dp->dn->dirents[idx] == -1 || dp->dn->dirents[idx ] == nentries) ? (void) (0) : __assert_fail ("dp->dn->dirents[idx] == -1 || dp->dn->dirents[idx] == nentries" , "dir.c", 494, __PRETTY_FUNCTION__)) |
| 494 | || dp->dn->dirents[idx] == nentries)((dp->dn->dirents[idx] == -1 || dp->dn->dirents[idx ] == nentries) ? (void) (0) : __assert_fail ("dp->dn->dirents[idx] == -1 || dp->dn->dirents[idx] == nentries" , "dir.c", 494, __PRETTY_FUNCTION__)); |
| 495 | dp->dn->dirents[idx] = nentries; |
| 496 | |
| 497 | return ENOENT((0x10 << 26) | ((2) & 0x3fff)); |
| 498 | } |
| 499 | |
| 500 | /* We have found the required name. */ |
| 501 | |
| 502 | if (ds && type == CREATE) |
| 503 | ds->type = LOOKUP; /* it's invalid now */ |
| 504 | else if (ds && (type == REMOVE || type == RENAME)) |
| 505 | { |
| 506 | ds->type = type; |
| 507 | ds->stat = HERE_TIS; |
| 508 | ds->entry = entry; |
| 509 | ds->idx = idx; |
| 510 | ds->preventry = (struct ext2_dir_entry_2 *) prevoff; |
| 511 | } |
| 512 | |
| 513 | *inum = entry->inode; |
| 514 | return 0; |
| 515 | } |
| 516 | |
| 517 | /* Following a lookup call for CREATE, this adds a node to a directory. |
| 518 | DP is the directory to be modified; NAME is the name to be entered; |
| 519 | NP is the node being linked in; DS is the cached information returned |
| 520 | by lookup; CRED describes the user making the call. This call may |
| 521 | only be made if the directory has been held locked continuously since |
| 522 | the preceding lookup call, and only if that call returned ENOENT. */ |
| 523 | error_t |
| 524 | diskfs_direnter_hard (struct node *dp, const char *name, struct node *np, |
| 525 | struct dirstat *ds, struct protid *cred) |
| 526 | { |
| 527 | struct ext2_dir_entry_2 *new; |
| 528 | int namelen = strlen (name); |
| 529 | int needed = EXT2_DIR_REC_LEN (namelen)(((namelen) + 8 + (4 - 1)) & ~(4 - 1)); |
| 530 | int oldneeded; |
| 531 | vm_address_t fromoff, tooff; |
| 532 | int totfreed; |
| 533 | error_t err; |
| 534 | size_t oldsize = 0; |
| 535 | |
| 536 | assert (ds->type == CREATE)((ds->type == CREATE) ? (void) (0) : __assert_fail ("ds->type == CREATE" , "dir.c", 536, __PRETTY_FUNCTION__)); |
| 537 | |
| 538 | assert (!diskfs_readonly)((!diskfs_readonly) ? (void) (0) : __assert_fail ("!diskfs_readonly" , "dir.c", 538, __PRETTY_FUNCTION__)); |
| 539 | |
| 540 | dp->dn_set_mtime = 1; |
| 541 | |
| 542 | /* Select a location for the new directory entry. Each branch of this |
| 543 | switch is responsible for setting NEW to point to the on-disk |
| 544 | directory entry being written, and setting NEW->rec_len appropriately. */ |
| 545 | |
| 546 | switch (ds->stat) |
| 547 | { |
| 548 | case TAKE: |
| 549 | /* We are supposed to consume this slot. */ |
| 550 | assert (ds->entry->inode == 0 && ds->entry->rec_len >= needed)((ds->entry->inode == 0 && ds->entry->rec_len >= needed) ? (void) (0) : __assert_fail ("ds->entry->inode == 0 && ds->entry->rec_len >= needed" , "dir.c", 550, __PRETTY_FUNCTION__)); |
| 551 | |
| 552 | new = ds->entry; |
| 553 | break; |
| 554 | |
| 555 | case SHRINK: |
| 556 | /* We are supposed to take the extra space at the end |
| 557 | of this slot. */ |
| 558 | oldneeded = EXT2_DIR_REC_LEN (ds->entry->name_len)(((ds->entry->name_len) + 8 + (4 - 1)) & ~(4 - 1)); |
| 559 | assert (ds->entry->rec_len - oldneeded >= needed)((ds->entry->rec_len - oldneeded >= needed) ? (void) (0) : __assert_fail ("ds->entry->rec_len - oldneeded >= needed" , "dir.c", 559, __PRETTY_FUNCTION__)); |
| 560 | |
| 561 | new = (struct ext2_dir_entry_2 *) ((vm_address_t) ds->entry + oldneeded); |
| 562 | |
| 563 | new->rec_len = ds->entry->rec_len - oldneeded; |
| 564 | ds->entry->rec_len = oldneeded; |
| 565 | break; |
| 566 | |
| 567 | case COMPRESS: |
| 568 | /* We are supposed to move all the entries to the |
| 569 | front of the block, giving each the minimum |
| 570 | necessary room. This should free up enough space |
| 571 | for the new entry. */ |
| 572 | fromoff = tooff = (vm_address_t) ds->entry; |
| 573 | |
| 574 | while (fromoff < (vm_address_t) ds->entry + DIRBLKSIZblock_size) |
| 575 | { |
| 576 | struct ext2_dir_entry_2 *from = (struct ext2_dir_entry_2 *)fromoff; |
| 577 | struct ext2_dir_entry_2 *to = (struct ext2_dir_entry_2 *) tooff; |
| 578 | int fromreclen = from->rec_len; |
| 579 | |
| 580 | if (from->inode != 0) |
| 581 | { |
| 582 | assert (fromoff >= tooff)((fromoff >= tooff) ? (void) (0) : __assert_fail ("fromoff >= tooff" , "dir.c", 582, __PRETTY_FUNCTION__)); |
| 583 | |
| 584 | memmove (to, from, fromreclen); |
| 585 | to->rec_len = EXT2_DIR_REC_LEN (to->name_len)(((to->name_len) + 8 + (4 - 1)) & ~(4 - 1)); |
| 586 | |
| 587 | tooff += to->rec_len; |
| 588 | } |
| 589 | fromoff += fromreclen; |
| 590 | } |
| 591 | |
| 592 | totfreed = (vm_address_t) ds->entry + DIRBLKSIZblock_size - tooff; |
| 593 | assert (totfreed >= needed)((totfreed >= needed) ? (void) (0) : __assert_fail ("totfreed >= needed" , "dir.c", 593, __PRETTY_FUNCTION__)); |
| 594 | |
| 595 | new = (struct ext2_dir_entry_2 *) tooff; |
| 596 | new->rec_len = totfreed; |
| 597 | break; |
| 598 | |
| 599 | case EXTEND: |
| 600 | /* Extend the file. */ |
| 601 | assert (needed <= DIRBLKSIZ)((needed <= block_size) ? (void) (0) : __assert_fail ("needed <= block_size" , "dir.c", 601, __PRETTY_FUNCTION__)); |
| 602 | |
| 603 | oldsize = dp->dn_stat.st_size; |
| 604 | if ((off_t)(oldsize + DIRBLKSIZblock_size) != (dp->dn_stat.st_size + DIRBLKSIZblock_size)) |
| 605 | { |
| 606 | /* We can't possibly map the whole directory in. */ |
| 607 | munmap ((caddr_t) ds->mapbuf, ds->mapextent); |
| 608 | return EOVERFLOW((0x10 << 26) | ((115) & 0x3fff)); |
| 609 | } |
| 610 | while (oldsize + DIRBLKSIZblock_size > dp->allocsize) |
| 611 | { |
| 612 | err = diskfs_grow (dp, oldsize + DIRBLKSIZblock_size, cred); |
| 613 | if (err) |
| 614 | { |
| 615 | munmap ((caddr_t) ds->mapbuf, ds->mapextent); |
| 616 | return err; |
| 617 | } |
| 618 | } |
| 619 | |
| 620 | new = (struct ext2_dir_entry_2 *) (ds->mapbuf + oldsize); |
| 621 | |
| 622 | dp->dn_stat.st_size = oldsize + DIRBLKSIZblock_size; |
| 623 | dp->dn_set_ctime = 1; |
| 624 | |
| 625 | new->rec_len = DIRBLKSIZblock_size; |
| 626 | break; |
| 627 | |
| 628 | default: |
| 629 | new = 0; |
| 630 | assert (! "impossible: bogus status field in dirstat")((! "impossible: bogus status field in dirstat") ? (void) (0) : __assert_fail ("! \"impossible: bogus status field in dirstat\"" , "dir.c", 630, __PRETTY_FUNCTION__)); |
| 631 | } |
| 632 | |
| 633 | /* NEW points to the directory entry being written, and its |
| 634 | rec_len field is already filled in. Now fill in the rest. */ |
| 635 | |
| 636 | new->inode = np->cache_id; |
| 637 | #if 0 |
| 638 | /* XXX We cannot enable this code because file types can change |
| 639 | (and conceivably quite often) with translator settings. |
| 640 | There is no way for the translator that determines the type of |
| 641 | the virtual node to cause all the directory entries linked to |
| 642 | its underlying inode to reflect the proper type. */ |
| 643 | new->file_type = (EXT2_HAS_INCOMPAT_FEATURE (sblock,( (sblock)->s_feature_incompat & (0x0002) ) |
| 644 | EXT2_FEATURE_INCOMPAT_FILETYPE)( (sblock)->s_feature_incompat & (0x0002) ) |
| 645 | ? file_type_ext2[IFTODT (np->dn_stat.st_mode & S_IFMT)(((np->dn_stat.st_mode & 0170000) & 0170000) >> 12)] |
| 646 | : 0); |
| 647 | #else |
| 648 | new->file_type = 0; |
| 649 | #endif |
| 650 | new->name_len = namelen; |
| 651 | memcpy (new->name, name, namelen); |
| 652 | |
| 653 | /* Mark the directory inode has having been written. */ |
| 654 | dp->dn->info.i_flags &= ~EXT2_BTREE_FL0x00001000; |
| 655 | dp->dn_set_mtime = 1; |
| 656 | |
| 657 | munmap ((caddr_t) ds->mapbuf, ds->mapextent); |
| 658 | |
| 659 | if (ds->stat != EXTEND) |
| 660 | { |
| 661 | /* If we are keeping count of this block, then keep the count up |
| 662 | to date. */ |
| 663 | if (dp->dn->dirents && dp->dn->dirents[ds->idx] != -1) |
| 664 | dp->dn->dirents[ds->idx]++; |
| 665 | } |
| 666 | else |
| 667 | { |
| 668 | int i; |
| 669 | /* It's cheap, so start a count here even if we aren't counting |
| 670 | anything at all. */ |
| 671 | if (dp->dn->dirents) |
| 672 | { |
| 673 | dp->dn->dirents = realloc (dp->dn->dirents, |
| 674 | (dp->dn_stat.st_size / DIRBLKSIZblock_size |
| 675 | * sizeof (int))); |
| 676 | for (i = oldsize / DIRBLKSIZblock_size; |
| 677 | i < dp->dn_stat.st_size / DIRBLKSIZblock_size; |
| 678 | i++) |
| 679 | dp->dn->dirents[i] = -1; |
| 680 | |
| 681 | dp->dn->dirents[ds->idx] = 1; |
| 682 | } |
| 683 | else |
| 684 | { |
| 685 | dp->dn->dirents = malloc (dp->dn_stat.st_size / DIRBLKSIZblock_size |
| 686 | * sizeof (int)); |
| 687 | for (i = 0; i < dp->dn_stat.st_size / DIRBLKSIZblock_size; i++) |
| 688 | dp->dn->dirents[i] = -1; |
| 689 | dp->dn->dirents[ds->idx] = 1; |
| 690 | } |
| 691 | } |
| 692 | |
| 693 | diskfs_file_update (dp, diskfs_synchronous); |
| 694 | |
| 695 | return 0; |
| 696 | } |
| 697 | |
| 698 | /* Following a lookup call for REMOVE, this removes the link from the |
| 699 | directory. DP is the directory being changed and DS is the cached |
| 700 | information returned from lookup. This call is only valid if the |
| 701 | directory has been locked continuously since the call to lookup, and |
| 702 | only if that call succeeded. */ |
| 703 | error_t |
| 704 | diskfs_dirremove_hard (struct node *dp, struct dirstat *ds) |
| 705 | { |
| 706 | assert (ds->type == REMOVE)((ds->type == REMOVE) ? (void) (0) : __assert_fail ("ds->type == REMOVE" , "dir.c", 706, __PRETTY_FUNCTION__)); |
| 707 | assert (ds->stat == HERE_TIS)((ds->stat == HERE_TIS) ? (void) (0) : __assert_fail ("ds->stat == HERE_TIS" , "dir.c", 707, __PRETTY_FUNCTION__)); |
| 708 | |
| 709 | assert (!diskfs_readonly)((!diskfs_readonly) ? (void) (0) : __assert_fail ("!diskfs_readonly" , "dir.c", 709, __PRETTY_FUNCTION__)); |
| 710 | |
| 711 | if (ds->preventry == 0) |
| 712 | ds->entry->inode = 0; |
| 713 | else |
| 714 | { |
| 715 | assert ((vm_address_t) ds->entry - (vm_address_t) ds->preventry(((vm_address_t) ds->entry - (vm_address_t) ds->preventry == ds->preventry->rec_len) ? (void) (0) : __assert_fail ("(vm_address_t) ds->entry - (vm_address_t) ds->preventry == ds->preventry->rec_len" , "dir.c", 716, __PRETTY_FUNCTION__)) |
| 716 | == ds->preventry->rec_len)(((vm_address_t) ds->entry - (vm_address_t) ds->preventry == ds->preventry->rec_len) ? (void) (0) : __assert_fail ("(vm_address_t) ds->entry - (vm_address_t) ds->preventry == ds->preventry->rec_len" , "dir.c", 716, __PRETTY_FUNCTION__)); |
| 717 | ds->preventry->rec_len += ds->entry->rec_len; |
| 718 | } |
| 719 | |
| 720 | dp->dn_set_mtime = 1; |
| 721 | dp->dn->info.i_flags &= ~EXT2_BTREE_FL0x00001000; |
| 722 | |
| 723 | munmap ((caddr_t) ds->mapbuf, ds->mapextent); |
| 724 | |
| 725 | /* If we are keeping count of this block, then keep the count up |
| 726 | to date. */ |
| 727 | if (dp->dn->dirents && dp->dn->dirents[ds->idx] != -1) |
| 728 | dp->dn->dirents[ds->idx]--; |
| 729 | |
| 730 | diskfs_file_update (dp, diskfs_synchronous); |
| 731 | |
| 732 | return 0; |
| 733 | } |
| 734 | |
| 735 | |
| 736 | /* Following a lookup call for RENAME, this changes the inode number |
| 737 | on a directory entry. DP is the directory being changed; NP is |
| 738 | the new node being linked in; DP is the cached information returned |
| 739 | by lookup. This call is only valid if the directory has been locked |
| 740 | continuously since the call to lookup, and only if that call |
| 741 | succeeded. */ |
| 742 | error_t |
| 743 | diskfs_dirrewrite_hard (struct node *dp, struct node *np, struct dirstat *ds) |
| 744 | { |
| 745 | assert (ds->type == RENAME)((ds->type == RENAME) ? (void) (0) : __assert_fail ("ds->type == RENAME" , "dir.c", 745, __PRETTY_FUNCTION__)); |
| 746 | assert (ds->stat == HERE_TIS)((ds->stat == HERE_TIS) ? (void) (0) : __assert_fail ("ds->stat == HERE_TIS" , "dir.c", 746, __PRETTY_FUNCTION__)); |
| 747 | |
| 748 | assert (!diskfs_readonly)((!diskfs_readonly) ? (void) (0) : __assert_fail ("!diskfs_readonly" , "dir.c", 748, __PRETTY_FUNCTION__)); |
| 749 | |
| 750 | ds->entry->inode = np->cache_id; |
| 751 | dp->dn_set_mtime = 1; |
| 752 | dp->dn->info.i_flags &= ~EXT2_BTREE_FL0x00001000; |
| 753 | |
| 754 | munmap ((caddr_t) ds->mapbuf, ds->mapextent); |
| 755 | |
| 756 | diskfs_file_update (dp, diskfs_synchronous); |
| 757 | |
| 758 | return 0; |
| 759 | } |
| 760 | |
| 761 | /* Tell if DP is an empty directory (has only "." and ".." entries). |
| 762 | This routine must be called from inside a catch_exception (). */ |
| 763 | int |
| 764 | diskfs_dirempty (struct node *dp, struct protid *cred) |
| 765 | { |
| 766 | error_t err; |
| 767 | vm_address_t buf = 0, curoff; |
| 768 | struct ext2_dir_entry_2 *entry; |
| 769 | int hit = 0; /* Found something in the directory. */ |
| 770 | memory_object_t memobj = diskfs_get_filemap (dp, VM_PROT_READ((vm_prot_t) 0x01)); |
| 771 | |
| 772 | if (memobj == MACH_PORT_NULL((mach_port_t) 0)) |
| 773 | /* XXX should reflect error properly. */ |
| 774 | return 0; |
| 775 | |
| 776 | err = vm_map (mach_task_self ()((__mach_task_self_ + 0)), &buf, dp->dn_stat.st_size, 0, |
| 777 | 1, memobj, 0, 0, VM_PROT_READ((vm_prot_t) 0x01), VM_PROT_READ((vm_prot_t) 0x01), 0); |
| 778 | mach_port_deallocate (mach_task_self ()((__mach_task_self_ + 0)), memobj); |
| 779 | assert (!err)((!err) ? (void) (0) : __assert_fail ("!err", "dir.c", 779, __PRETTY_FUNCTION__ )); |
| 780 | |
| 781 | diskfs_set_node_atime (dp); |
| 782 | |
| 783 | for (curoff = buf; |
| 784 | !hit && curoff < buf + dp->dn_stat.st_size; |
| 785 | curoff += entry->rec_len) |
| 786 | { |
| 787 | entry = (struct ext2_dir_entry_2 *) curoff; |
| 788 | |
| 789 | if (entry->inode != 0 |
| 790 | && (entry->name_len > 2 |
| 791 | || entry->name[0] != '.' |
| 792 | || (entry->name[1] != '.' |
| 793 | && entry->name[1] != '\0'))) |
| 794 | hit = 1; |
| 795 | } |
| 796 | |
| 797 | diskfs_set_node_atime (dp); |
| 798 | if (diskfs_synchronous) |
| 799 | diskfs_node_update (dp, 1); |
| 800 | |
| 801 | munmap ((caddr_t) buf, dp->dn_stat.st_size); |
| 802 | |
| 803 | return !hit; |
| 804 | } |
| 805 | |
| 806 | /* Make DS an invalid dirstat. */ |
| 807 | error_t |
| 808 | diskfs_drop_dirstat (struct node *dp, struct dirstat *ds) |
| 809 | { |
| 810 | if (ds->type != LOOKUP) |
| 811 | { |
| 812 | assert (ds->mapbuf)((ds->mapbuf) ? (void) (0) : __assert_fail ("ds->mapbuf" , "dir.c", 812, __PRETTY_FUNCTION__)); |
| 813 | munmap ((caddr_t) ds->mapbuf, ds->mapextent); |
| 814 | ds->type = LOOKUP; |
| 815 | } |
| 816 | return 0; |
| 817 | } |
| 818 | |
| 819 | |
| 820 | /* Count the entries in directory block NB for directory DP and |
| 821 | write the answer down in its dirents array. As a side affect |
| 822 | fill BUF with the block. */ |
| 823 | static error_t |
| 824 | count_dirents (struct node *dp, int nb, char *buf) |
| 825 | { |
| 826 | size_t amt; |
| 827 | char *offinblk; |
| 828 | struct ext2_dir_entry_2 *entry; |
| 829 | int count = 0; |
| 830 | error_t err; |
| 831 | |
| 832 | assert (dp->dn->dirents)((dp->dn->dirents) ? (void) (0) : __assert_fail ("dp->dn->dirents" , "dir.c", 832, __PRETTY_FUNCTION__)); |
| 833 | assert ((nb + 1) * DIRBLKSIZ <= dp->dn_stat.st_size)(((nb + 1) * block_size <= dp->dn_stat.st_size) ? (void ) (0) : __assert_fail ("(nb + 1) * block_size <= dp->dn_stat.st_size" , "dir.c", 833, __PRETTY_FUNCTION__)); |
| 834 | |
| 835 | err = diskfs_node_rdwr (dp, buf, nb * DIRBLKSIZblock_size, DIRBLKSIZblock_size, 0, 0, &amt); |
| 836 | if (err) |
| 837 | return err; |
| 838 | assert (amt == DIRBLKSIZ)((amt == block_size) ? (void) (0) : __assert_fail ("amt == block_size" , "dir.c", 838, __PRETTY_FUNCTION__)); |
| 839 | |
| 840 | for (offinblk = buf; |
| 841 | offinblk < buf + DIRBLKSIZblock_size; |
| 842 | offinblk += entry->rec_len) |
| 843 | { |
| 844 | entry = (struct ext2_dir_entry_2 *) offinblk; |
| 845 | if (entry->inode) |
| 846 | count++; |
| 847 | } |
| 848 | |
| 849 | assert (dp->dn->dirents[nb] == -1 || dp->dn->dirents[nb] == count)((dp->dn->dirents[nb] == -1 || dp->dn->dirents[nb ] == count) ? (void) (0) : __assert_fail ("dp->dn->dirents[nb] == -1 || dp->dn->dirents[nb] == count" , "dir.c", 849, __PRETTY_FUNCTION__)); |
| 850 | dp->dn->dirents[nb] = count; |
| 851 | return 0; |
| 852 | } |
| 853 | |
| 854 | /* Returned directory entries are aligned to blocks this many bytes long. |
| 855 | Must be a power of two. */ |
| 856 | #define DIRENT_ALIGN4 4 |
| 857 | |
| 858 | /* Implement the diskfs_get_directs callback as described in |
| 859 | <hurd/diskfs.h>. */ |
| 860 | error_t |
| 861 | diskfs_get_directs (struct node *dp, |
| 862 | int entry, |
| 863 | int nentries, |
| 864 | char **data, |
| 865 | size_t *datacnt, |
| 866 | vm_size_t bufsiz, |
| 867 | int *amt) |
| 868 | { |
| 869 | int blkno; |
| 870 | int nblks; |
| 871 | int curentry; |
| 872 | char buf[DIRBLKSIZblock_size]; |
| 873 | char *bufp; |
| 874 | int bufvalid; |
| 875 | error_t err; |
| 876 | int i; |
| 877 | char *datap; |
| 878 | struct ext2_dir_entry_2 *entryp; |
| 879 | int allocsize; |
| 880 | size_t checklen; |
| 881 | struct dirent *userp; |
| 882 | |
| 883 | nblks = dp->dn_stat.st_size/DIRBLKSIZblock_size; |
| 884 | |
| 885 | if (!dp->dn->dirents) |
| 886 | { |
| 887 | dp->dn->dirents = malloc (nblks * sizeof (int)); |
| 888 | for (i = 0; i < nblks; i++) |
| 889 | dp->dn->dirents[i] = -1; |
| 890 | } |
| 891 | |
| 892 | /* Scan through the entries to find ENTRY. If we encounter |
| 893 | a -1 in the process then stop to fill it. When we run |
| 894 | off the end, ENTRY is too big. */ |
| 895 | curentry = 0; |
| 896 | bufvalid = 0; |
| 897 | for (blkno = 0; blkno < nblks; blkno++) |
| 898 | { |
| 899 | if (dp->dn->dirents[blkno] == -1) |
| 900 | { |
| 901 | err = count_dirents (dp, blkno, buf); |
| 902 | if (err) |
| 903 | return err; |
| 904 | bufvalid = 1; |
| 905 | } |
| 906 | |
| 907 | if (curentry + dp->dn->dirents[blkno] > entry) |
| 908 | /* ENTRY starts in this block. */ |
| 909 | break; |
| 910 | |
| 911 | curentry += dp->dn->dirents[blkno]; |
| 912 | |
| 913 | bufvalid = 0; |
| 914 | } |
| 915 | |
| 916 | if (blkno == nblks) |
| 917 | { |
| 918 | /* We reached the end of the directory without seeing ENTRY. |
| 919 | This is treated as an EOF condition, meaning we return |
| 920 | success with empty results. */ |
| 921 | *datacnt = 0; |
| 922 | *amt = 0; |
| 923 | return 0; |
| 924 | } |
| 925 | |
| 926 | /* Allocate enough space to hold the maximum we might return */ |
| 927 | if (!bufsiz || bufsiz > dp->dn_stat.st_size) |
| 928 | /* Allocate enough to return the entire directory. Since ext2's |
| 929 | directory format is different than the format used to return the |
| 930 | entries, we allocate enough to hold the on disk directory plus |
| 931 | whatever extra would be necessary in the worst-case. */ |
| 932 | { |
| 933 | /* The minimum size of an ext2fs directory entry. */ |
| 934 | size_t min_entry_size = EXT2_DIR_REC_LEN (0)(((0) + 8 + (4 - 1)) & ~(4 - 1)); |
| 935 | /* The minimum size of a returned dirent entry. The +1 is for '\0'. */ |
| 936 | size_t min_dirent_size = offsetof (struct dirent, d_name)__builtin_offsetof(struct dirent, d_name) + 1; |
| 937 | /* The maximum possible number of ext2fs dir entries in this dir. */ |
| 938 | size_t max_entries = dp->dn_stat.st_size / min_entry_size; |
| 939 | /* The maximum difference in size per directory entry. */ |
| 940 | size_t entry_extra = |
| 941 | DIRENT_ALIGN4 |
| 942 | + (min_dirent_size > min_entry_size |
| 943 | ? min_dirent_size - min_entry_size : 0); |
| 944 | |
| 945 | allocsize = round_page (dp->dn_stat.st_size + max_entries * entry_extra)((((vm_offset_t) (dp->dn_stat.st_size + max_entries * entry_extra ) + __vm_page_size - 1) / __vm_page_size) * __vm_page_size); |
| 946 | } |
| 947 | else |
| 948 | allocsize = round_page (bufsiz)((((vm_offset_t) (bufsiz) + __vm_page_size - 1) / __vm_page_size ) * __vm_page_size); |
| 949 | |
| 950 | if (allocsize > *datacnt) |
| 951 | *data = mmap (0, allocsize, PROT_READ0x04|PROT_WRITE0x02, MAP_ANON0x0002, 0, 0); |
| 952 | |
| 953 | /* Set bufp appropriately */ |
| 954 | bufp = buf; |
| 955 | if (curentry != entry) |
| 956 | { |
| 957 | /* Look through the block to find out where to start, |
| 958 | setting bufp appropriately. */ |
| 959 | if (!bufvalid) |
| 960 | { |
| 961 | err = diskfs_node_rdwr (dp, buf, blkno * DIRBLKSIZblock_size, DIRBLKSIZblock_size, |
| 962 | 0, 0, &checklen); |
| 963 | if (err) |
| 964 | return err; |
| 965 | assert (checklen == DIRBLKSIZ)((checklen == block_size) ? (void) (0) : __assert_fail ("checklen == block_size" , "dir.c", 965, __PRETTY_FUNCTION__)); |
| 966 | bufvalid = 1; |
| 967 | } |
| 968 | for (i = 0, bufp = buf; |
| 969 | i < entry - curentry && bufp - buf < DIRBLKSIZblock_size; |
| 970 | bufp += ((struct ext2_dir_entry_2 *)bufp)->rec_len, i++) |
| 971 | ; |
| 972 | /* Make sure we didn't run off the end. */ |
| 973 | assert (bufp - buf < DIRBLKSIZ)((bufp - buf < block_size) ? (void) (0) : __assert_fail ("bufp - buf < block_size" , "dir.c", 973, __PRETTY_FUNCTION__)); |
| 974 | } |
| 975 | |
| 976 | i = 0; |
| 977 | datap = *data; |
| 978 | |
| 979 | /* Copy the entries, one at a time. */ |
| 980 | while (((nentries == -1) || (i < nentries)) |
| 981 | && (!bufsiz || (datap - *data < bufsiz) ) |
| 982 | && blkno < nblks) |
| 983 | { |
| 984 | if (!bufvalid) |
| 985 | { |
| 986 | err = diskfs_node_rdwr (dp, buf, blkno * DIRBLKSIZblock_size, DIRBLKSIZblock_size, |
| 987 | 0, 0, &checklen); |
| 988 | if (err) |
| 989 | return err; |
| 990 | assert (checklen == DIRBLKSIZ)((checklen == block_size) ? (void) (0) : __assert_fail ("checklen == block_size" , "dir.c", 990, __PRETTY_FUNCTION__)); |
| 991 | bufvalid = 1; |
| 992 | bufp = buf; |
| 993 | } |
| 994 | |
| 995 | entryp = (struct ext2_dir_entry_2 *)bufp; |
| 996 | |
| 997 | if (entryp->inode) |
| 998 | { |
| 999 | int rec_len; |
| 1000 | int name_len = entryp->name_len; |
| 1001 | |
| 1002 | userp = (struct dirent *) datap; |
| 1003 | |
| 1004 | /* Length is structure before the name + the name + '\0', all |
| 1005 | padded to a four-byte alignment. */ |
| 1006 | rec_len = |
| 1007 | ((offsetof (struct dirent, d_name)__builtin_offsetof(struct dirent, d_name) |
| 1008 | + name_len + 1 |
| 1009 | + (DIRENT_ALIGN4 - 1)) |
| 1010 | & ~(DIRENT_ALIGN4 - 1)); |
| 1011 | |
| 1012 | /* See if this record would run over the end of the return buffer. */ |
| 1013 | if (bufsiz == 0) |
| 1014 | /* It shouldn't ever, as we calculated the worst case size. */ |
| 1015 | assert (datap + rec_len <= *data + allocsize)((datap + rec_len <= *data + allocsize) ? (void) (0) : __assert_fail ("datap + rec_len <= *data + allocsize", "dir.c", 1015, __PRETTY_FUNCTION__ )); |
| 1016 | else |
| 1017 | /* It's ok if it does, just leave off returning this entry. */ |
| 1018 | if (datap + rec_len > *data + allocsize) |
| 1019 | break; |
| 1020 | |
| 1021 | userp->d_filenod_ino = entryp->inode; |
| 1022 | userp->d_reclen = rec_len; |
| 1023 | userp->d_namlen = name_len; |
| 1024 | |
| 1025 | #if 0 |
| 1026 | /* We don't bother to check the EXT2_FEATURE_INCOMPAT_FILETYPE |
| 1027 | flag in the superblock, because in old filesystems the |
| 1028 | file_type field is the high byte of the length field and is |
| 1029 | always zero because names cannot be that long. */ |
| 1030 | if (entryp->file_type < EXT2_FT_MAX8) |
| 1031 | userp->d_type = ext2_file_type[entryp->file_type]; |
| 1032 | else |
| 1033 | { |
| 1034 | ext2_warning ("bad type %d in directory entry: " |
| 1035 | "inode: %d offset: %d", |
| 1036 | entryp->file_type, |
| 1037 | dp->cache_id, |
| 1038 | blkno * DIRBLKSIZblock_size + bufp - buf); |
| 1039 | userp->d_type = DT_UNKNOWNDT_UNKNOWN; |
| 1040 | } |
| 1041 | #else |
| 1042 | /* XXX |
| 1043 | For complex reasons it might not be correct to return |
| 1044 | the filesystem's d_type value to the user. */ |
| 1045 | userp->d_type = DT_UNKNOWNDT_UNKNOWN; |
| 1046 | #endif |
| 1047 | memcpy (userp->d_name, entryp->name, name_len); |
| 1048 | userp->d_name[name_len] = '\0'; |
| 1049 | |
| 1050 | datap += rec_len; |
| 1051 | i++; |
| 1052 | } |
| 1053 | |
| 1054 | if (entryp->rec_len == 0) |
| 1055 | { |
| 1056 | ext2_warning ("zero length directory entry: inode: %Ld offset: %zd", |
| 1057 | dp->cache_id, |
| 1058 | blkno * DIRBLKSIZblock_size + bufp - buf); |
| 1059 | return EIO((0x10 << 26) | ((5) & 0x3fff)); |
| 1060 | } |
| 1061 | |
| 1062 | bufp += entryp->rec_len; |
| 1063 | if (bufp - buf == DIRBLKSIZblock_size) |
| 1064 | { |
| 1065 | blkno++; |
| 1066 | bufvalid = 0; |
| 1067 | } |
| 1068 | else if (bufp - buf > DIRBLKSIZblock_size) |
| 1069 | { |
| 1070 | ext2_warning ("directory entry too long: inode: %Ld offset: %zd", |
| 1071 | dp->cache_id, |
| 1072 | blkno * DIRBLKSIZblock_size + bufp - buf - entryp->rec_len); |
| 1073 | return EIO((0x10 << 26) | ((5) & 0x3fff)); |
| 1074 | } |
| 1075 | } |
| 1076 | |
| 1077 | /* We've copied all we can. If we allocated our own array |
| 1078 | but didn't fill all of it, then free whatever memory we didn't use. */ |
| 1079 | if (allocsize > *datacnt) |
| 1080 | { |
| 1081 | if (round_page (datap - *data)((((vm_offset_t) (datap - *data) + __vm_page_size - 1) / __vm_page_size ) * __vm_page_size) < allocsize) |
| 1082 | munmap ((caddr_t) (*data + round_page (datap - *data)((((vm_offset_t) (datap - *data) + __vm_page_size - 1) / __vm_page_size ) * __vm_page_size)), |
| 1083 | allocsize - round_page (datap - *data)((((vm_offset_t) (datap - *data) + __vm_page_size - 1) / __vm_page_size ) * __vm_page_size)); |
| 1084 | } |
| 1085 | |
| 1086 | /* Set variables for return */ |
| 1087 | *datacnt = datap - *data; |
| 1088 | *amt = i; |
| 1089 | return 0; |
| 1090 | } |