fs/hfs/hfs.c

   1 /*
   2  * libhfs - library for reading and writing Macintosh HFS volumes
   3  * Copyright (C) 1996-1998 Robert Leslie
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  18  * MA 02110-1301, USA.
  19  *
  20  * $Id: hfs.c,v 1.15 1998/11/02 22:09:00 rob Exp $
  21  */
  22
  23 #include "config.h"
  24 #include "libhfs.h"
  25 #include "data.h"
  26 #include "block.h"
  27 #include "medium.h"
  28 #include "file.h"
  29 #include "btree.h"
  30 #include "node.h"
  31 #include "record.h"
  32 #include "volume.h"
  33
  34 const char *hfs_error = "no error";     /* static error string */
  35
  36 hfsvol *hfs_mounts;                     /* linked list of mounted volumes */
  37
  38 static
  39 hfsvol *curvol;                         /* current volume */
  40
  41
  42 /*
  43  * NAME:        getvol()
  44  * DESCRIPTION: validate a volume reference
  45  */
  46 static
  47 int getvol(hfsvol **vol)
  48 {
  49   if (*vol == NULL)
  50     {
  51       if (curvol == NULL)
  52         ERROR(EINVAL, "no volume is current");
  53
  54       *vol = curvol;
  55     }
  56
  57   return 0;
  58
  59 fail:
  60   return -1;
  61 }
  62
  63 /* High-Level Volume Routines ============================================== */
  64
  65 /*
  66  * NAME:        hfs->mount()
  67  * DESCRIPTION: open an HFS volume; return volume descriptor or 0 (error)
  68  */
  69 hfsvol *hfs_mount( int os_fd, int pnum)
  70 {
  71   hfsvol *vol, *check;
  72   int mode = HFS_MODE_RDONLY;
  73
  74   /* see if the volume is already mounted */
  75   for (check = hfs_mounts; check; check = check->next)
  76     {
  77       if (check->pnum == pnum && v_same(check, os_fd) == 1)
  78         {
  79             vol = check;
  80             goto done;
  81         }
  82     }
  83
  84   vol = ALLOC(hfsvol, 1);
  85   if (vol == NULL)
  86     ERROR(ENOMEM, NULL);
  87
  88   v_init(vol, mode);
  89
  90   vol->flags |= HFS_VOL_READONLY;
  91   if( v_open(vol, os_fd) == -1 )
  92           goto fail;
  93
  94   /* mount the volume */
  95
  96   if (v_geometry(vol, pnum) == -1 ||
  97       v_mount(vol) == -1)
  98     goto fail;
  99
 100   /* add to linked list of volumes */
 101
 102   vol->prev = NULL;
 103   vol->next = hfs_mounts;
 104
 105   if (hfs_mounts)
 106     hfs_mounts->prev = vol;
 107
 108   hfs_mounts = vol;
 109
 110 done:
 111   ++vol->refs;
 112   curvol = vol;
 113
 114   return vol;
 115
 116 fail:
 117   if (vol)
 118     {
 119       v_close(vol);
 120       FREE(vol);
 121     }
 122
 123   return NULL;
 124 }
 125
 126
 127 /*
 128  * NAME:        hfs->umount()
 129  * DESCRIPTION: close an HFS volume
 130  */
 131 int hfs_umount(hfsvol *vol)
 132 {
 133   int result = 0;
 134
 135   if (getvol(&vol) == -1)
 136     goto fail;
 137
 138   if (--vol->refs)
 139     {
 140       goto done;
 141     }
 142
 143   /* close all open files and directories */
 144
 145   while (vol->files)
 146     {
 147       if (hfs_close(vol->files) == -1)
 148         result = -1;
 149     }
 150
 151   while (vol->dirs)
 152     {
 153       if (hfs_closedir(vol->dirs) == -1)
 154         result = -1;
 155     }
 156
 157   /* close medium */
 158
 159   if (v_close(vol) == -1)
 160     result = -1;
 161
 162   /* remove from linked list of volumes */
 163
 164   if (vol->prev)
 165     vol->prev->next = vol->next;
 166   if (vol->next)
 167     vol->next->prev = vol->prev;
 168
 169   if (vol == hfs_mounts)
 170     hfs_mounts = vol->next;
 171   if (vol == curvol)
 172     curvol = NULL;
 173
 174   FREE(vol);
 175
 176 done:
 177   return result;
 178
 179 fail:
 180   return -1;
 181 }
 182
 183 /*
 184  * NAME:        hfs->umountall()
 185  * DESCRIPTION: unmount all mounted volumes
 186  */
 187 void hfs_umountall(void)
 188 {
 189   while (hfs_mounts)
 190     hfs_umount(hfs_mounts);
 191 }
 192
 193 /*
 194  * NAME:        hfs->getvol()
 195  * DESCRIPTION: return a pointer to a mounted volume
 196  */
 197 hfsvol *hfs_getvol(const char *name)
 198 {
 199   hfsvol *vol;
 200
 201   if (name == NULL)
 202     return curvol;
 203
 204   for (vol = hfs_mounts; vol; vol = vol->next)
 205     {
 206       if (d_relstring(name, vol->mdb.drVN) == 0)
 207         return vol;
 208     }
 209
 210   return NULL;
 211 }
 212
 213 /*
 214  * NAME:        hfs->setvol()
 215  * DESCRIPTION: change the current volume
 216  */
 217 void hfs_setvol(hfsvol *vol)
 218 {
 219   curvol = vol;
 220 }
 221
 222 /*
 223  * NAME:        hfs->vstat()
 224  * DESCRIPTION: return volume statistics
 225  */
 226 int hfs_vstat(hfsvol *vol, hfsvolent *ent)
 227 {
 228   if (getvol(&vol) == -1)
 229     goto fail;
 230
 231   strcpy(ent->name, vol->mdb.drVN);
 232
 233   ent->flags     = (vol->flags & HFS_VOL_READONLY) ? HFS_ISLOCKED : 0;
 234
 235   ent->totbytes  = vol->mdb.drNmAlBlks * vol->mdb.drAlBlkSiz;
 236   ent->freebytes = vol->mdb.drFreeBks  * vol->mdb.drAlBlkSiz;
 237
 238   ent->alblocksz = vol->mdb.drAlBlkSiz;
 239   ent->clumpsz   = vol->mdb.drClpSiz;
 240
 241   ent->numfiles  = vol->mdb.drFilCnt;
 242   ent->numdirs   = vol->mdb.drDirCnt;
 243
 244   ent->crdate    = d_ltime(vol->mdb.drCrDate);
 245   ent->mddate    = d_ltime(vol->mdb.drLsMod);
 246   ent->bkdate    = d_ltime(vol->mdb.drVolBkUp);
 247
 248   ent->blessed   = vol->mdb.drFndrInfo[0];
 249
 250   return 0;
 251
 252 fail:
 253   return -1;
 254 }
 255
 256
 257 /* High-Level Directory Routines =========================================== */
 258
 259 /*
 260  * NAME:        hfs->chdir()
 261  * DESCRIPTION: change current HFS directory
 262  */
 263 int hfs_chdir(hfsvol *vol, const char *path)
 264 {
 265   CatDataRec data;
 266
 267   if (getvol(&vol) == -1 ||
 268       v_resolve(&vol, path, &data, NULL, NULL, NULL) <= 0)
 269     goto fail;
 270
 271   if (data.cdrType != cdrDirRec)
 272     ERROR(ENOTDIR, NULL);
 273
 274   vol->cwd = data.u.dir.dirDirID;
 275
 276   return 0;
 277
 278 fail:
 279   return -1;
 280 }
 281
 282 /*
 283  * NAME:        hfs->getcwd()
 284  * DESCRIPTION: return the current working directory ID
 285  */
 286 unsigned long hfs_getcwd(hfsvol *vol)
 287 {
 288   if (getvol(&vol) == -1)
 289     return 0;
 290
 291   return vol->cwd;
 292 }
 293
 294 /*
 295  * NAME:        hfs->setcwd()
 296  * DESCRIPTION: set the current working directory ID
 297  */
 298 int hfs_setcwd(hfsvol *vol, unsigned long id)
 299 {
 300   if (getvol(&vol) == -1)
 301     goto fail;
 302
 303   if (id == vol->cwd)
 304     goto done;
 305
 306   /* make sure the directory exists */
 307
 308   if (v_getdthread(vol, id, NULL, NULL) <= 0)
 309     goto fail;
 310
 311   vol->cwd = id;
 312
 313 done:
 314   return 0;
 315
 316 fail:
 317   return -1;
 318 }
 319
 320 /*
 321  * NAME:        hfs->dirinfo()
 322  * DESCRIPTION: given a directory ID, return its (name and) parent ID
 323  */
 324 int hfs_dirinfo(hfsvol *vol, unsigned long *id, char *name)
 325 {
 326   CatDataRec thread;
 327
 328   if (getvol(&vol) == -1 ||
 329       v_getdthread(vol, *id, &thread, NULL) <= 0)
 330     goto fail;
 331
 332   *id = thread.u.dthd.thdParID;
 333
 334   if (name)
 335     strcpy(name, thread.u.dthd.thdCName);
 336
 337   return 0;
 338
 339 fail:
 340   return -1;
 341 }
 342
 343 /*
 344  * NAME:        hfs->opendir()
 345  * DESCRIPTION: prepare to read the contents of a directory
 346  */
 347 hfsdir *hfs_opendir(hfsvol *vol, const char *path)
 348 {
 349   hfsdir *dir = NULL;
 350   CatKeyRec key;
 351   CatDataRec data;
 352   byte pkey[HFS_CATKEYLEN];
 353
 354   if (getvol(&vol) == -1)
 355     goto fail;
 356
 357   dir = ALLOC(hfsdir, 1);
 358   if (dir == NULL)
 359     ERROR(ENOMEM, NULL);
 360
 361   dir->vol = vol;
 362
 363   if (*path == 0)
 364     {
 365       /* meta-directory containing root dirs from all mounted volumes */
 366
 367       dir->dirid = 0;
 368       dir->vptr  = hfs_mounts;
 369     }
 370   else
 371     {
 372       if (v_resolve(&vol, path, &data, NULL, NULL, NULL) <= 0)
 373         goto fail;
 374
 375       if (data.cdrType != cdrDirRec)
 376         ERROR(ENOTDIR, NULL);
 377
 378       dir->dirid = data.u.dir.dirDirID;
 379       dir->vptr  = NULL;
 380
 381       r_makecatkey(&key, dir->dirid, "");
 382       r_packcatkey(&key, pkey, NULL);
 383
 384       if (bt_search(&vol->cat, pkey, &dir->n) <= 0)
 385         goto fail;
 386     }
 387
 388   dir->prev = NULL;
 389   dir->next = vol->dirs;
 390
 391   if (vol->dirs)
 392     vol->dirs->prev = dir;
 393
 394   vol->dirs = dir;
 395
 396   return dir;
 397
 398 fail:
 399   FREE(dir);
 400   return NULL;
 401 }
 402
 403 /*
 404  * NAME:        hfs->readdir()
 405  * DESCRIPTION: return the next entry in the directory
 406  */
 407 int hfs_readdir(hfsdir *dir, hfsdirent *ent)
 408 {
 409   CatKeyRec key;
 410   CatDataRec data;
 411   const byte *ptr;
 412
 413   if (dir->dirid == 0)
 414     {
 415       hfsvol *vol;
 416       char cname[HFS_MAX_FLEN + 1];
 417
 418       for (vol = hfs_mounts; vol; vol = vol->next)
 419         {
 420           if (vol == dir->vptr)
 421             break;
 422         }
 423
 424       if (vol == NULL)
 425         ERROR(ENOENT, "no more entries");
 426
 427       if (v_getdthread(vol, HFS_CNID_ROOTDIR, &data, NULL) <= 0 ||
 428           v_catsearch(vol, HFS_CNID_ROOTPAR, data.u.dthd.thdCName,
 429                       &data, cname, NULL) <= 0)
 430         goto fail;
 431
 432       r_unpackdirent(HFS_CNID_ROOTPAR, cname, &data, ent);
 433
 434       dir->vptr = vol->next;
 435
 436       goto done;
 437     }
 438
 439   if (dir->n.rnum == -1)
 440     ERROR(ENOENT, "no more entries");
 441
 442   while (1)
 443     {
 444       ++dir->n.rnum;
 445
 446       while (dir->n.rnum >= dir->n.nd.ndNRecs)
 447         {
 448           if (dir->n.nd.ndFLink == 0)
 449             {
 450               dir->n.rnum = -1;
 451               ERROR(ENOENT, "no more entries");
 452             }
 453
 454           if (bt_getnode(&dir->n, dir->n.bt, dir->n.nd.ndFLink) == -1)
 455             {
 456               dir->n.rnum = -1;
 457               goto fail;
 458             }
 459
 460           dir->n.rnum = 0;
 461         }
 462
 463       ptr = HFS_NODEREC(dir->n, dir->n.rnum);
 464
 465       r_unpackcatkey(ptr, &key);
 466
 467       if (key.ckrParID != dir->dirid)
 468         {
 469           dir->n.rnum = -1;
 470           ERROR(ENOENT, "no more entries");
 471         }
 472
 473       r_unpackcatdata(HFS_RECDATA(ptr), &data);
 474
 475       switch (data.cdrType)
 476         {
 477         case cdrDirRec:
 478         case cdrFilRec:
 479           r_unpackdirent(key.ckrParID, key.ckrCName, &data, ent);
 480           goto done;
 481
 482         case cdrThdRec:
 483         case cdrFThdRec:
 484           break;
 485
 486         default:
 487           dir->n.rnum = -1;
 488           ERROR(EIO, "unexpected directory entry found");
 489         }
 490     }
 491
 492 done:
 493   return 0;
 494
 495 fail:
 496   return -1;
 497 }
 498
 499 /*
 500  * NAME:        hfs->closedir()
 501  * DESCRIPTION: stop reading a directory
 502  */
 503 int hfs_closedir(hfsdir *dir)
 504 {
 505   hfsvol *vol = dir->vol;
 506
 507   if (dir->prev)
 508     dir->prev->next = dir->next;
 509   if (dir->next)
 510     dir->next->prev = dir->prev;
 511   if (dir == vol->dirs)
 512     vol->dirs = dir->next;
 513
 514   FREE(dir);
 515
 516   return 0;
 517 }
 518
 519 /* High-Level File Routines ================================================ */
 520
 521 /*
 522  * NAME:        hfs->open()
 523  * DESCRIPTION: prepare a file for I/O
 524  */
 525 hfsfile *hfs_open(hfsvol *vol, const char *path)
 526 {
 527   hfsfile *file = NULL;
 528
 529   if (getvol(&vol) == -1)
 530     goto fail;
 531
 532   file = ALLOC(hfsfile, 1);
 533   if (file == NULL)
 534     ERROR(ENOMEM, NULL);
 535
 536   if (v_resolve(&vol, path, &file->cat, &file->parid, file->name, NULL) <= 0)
 537     goto fail;
 538
 539   if (file->cat.cdrType != cdrFilRec)
 540     ERROR(EISDIR, NULL);
 541
 542   /* package file handle for user */
 543
 544   file->vol   = vol;
 545   file->flags = 0;
 546
 547   f_selectfork(file, fkData);
 548
 549   file->prev = NULL;
 550   file->next = vol->files;
 551
 552   if (vol->files)
 553     vol->files->prev = file;
 554
 555   vol->files = file;
 556
 557   return file;
 558
 559 fail:
 560   FREE(file);
 561   return NULL;
 562 }
 563
 564 /*
 565  * NAME:        hfs->setfork()
 566  * DESCRIPTION: select file fork for I/O operations
 567  */
 568 int hfs_setfork(hfsfile *file, int fork)
 569 {
 570   int result = 0;
 571
 572   f_selectfork(file, fork ? fkRsrc : fkData);
 573
 574   return result;
 575 }
 576
 577 /*
 578  * NAME:        hfs->getfork()
 579  * DESCRIPTION: return the current fork for I/O operations
 580  */
 581 int hfs_getfork(hfsfile *file)
 582 {
 583   return file->fork != fkData;
 584 }
 585
 586 /*
 587  * NAME:        hfs->read()
 588  * DESCRIPTION: read from an open file
 589  */
 590 unsigned long hfs_read(hfsfile *file, void *buf, unsigned long len)
 591 {
 592   unsigned long *lglen, count;
 593   byte *ptr = buf;
 594
 595   f_getptrs(file, NULL, &lglen, NULL);
 596
 597   if (file->pos + len > *lglen)
 598     len = *lglen - file->pos;
 599
 600   count = len;
 601   while (count)
 602     {
 603       unsigned long bnum, offs, chunk;
 604
 605       bnum  = file->pos >> HFS_BLOCKSZ_BITS;
 606       offs  = file->pos & (HFS_BLOCKSZ - 1);
 607
 608       chunk = HFS_BLOCKSZ - offs;
 609       if (chunk > count)
 610         chunk = count;
 611
 612       if (offs == 0 && chunk == HFS_BLOCKSZ)
 613         {
 614           if (f_getblock(file, bnum, (block *) ptr) == -1)
 615             goto fail;
 616         }
 617       else
 618         {
 619           block b;
 620
 621           if (f_getblock(file, bnum, &b) == -1)
 622             goto fail;
 623
 624           memcpy(ptr, b + offs, chunk);
 625         }
 626
 627       ptr += chunk;
 628
 629       file->pos += chunk;
 630       count     -= chunk;
 631     }
 632
 633   return len;
 634
 635 fail:
 636   return -1;
 637 }
 638
 639 /*
 640  * NAME:        hfs->seek()
 641  * DESCRIPTION: change file seek pointer
 642  */
 643 unsigned long hfs_seek(hfsfile *file, long offset, int from)
 644 {
 645   unsigned long *lglen, newpos;
 646
 647   f_getptrs(file, NULL, &lglen, NULL);
 648
 649   switch (from)
 650     {
 651     case HFS_SEEK_SET:
 652       newpos = (offset < 0) ? 0 : offset;
 653       break;
 654
 655     case HFS_SEEK_CUR:
 656       if (offset < 0 && (unsigned long) -offset > file->pos)
 657         newpos = 0;
 658       else
 659         newpos = file->pos + offset;
 660       break;
 661
 662     case HFS_SEEK_END:
 663       if (offset < 0 && (unsigned long) -offset > *lglen)
 664         newpos = 0;
 665       else
 666         newpos = *lglen + offset;
 667       break;
 668
 669     default:
 670       ERROR(EINVAL, NULL);
 671     }
 672
 673   if (newpos > *lglen)
 674     newpos = *lglen;
 675
 676   file->pos = newpos;
 677
 678   return newpos;
 679
 680 fail:
 681   return -1;
 682 }
 683
 684 /*
 685  * NAME:        hfs->close()
 686  * DESCRIPTION: close a file
 687  */
 688 int hfs_close(hfsfile *file)
 689 {
 690   hfsvol *vol = file->vol;
 691   int result = 0;
 692
 693   if (file->prev)
 694     file->prev->next = file->next;
 695   if (file->next)
 696     file->next->prev = file->prev;
 697   if (file == vol->files)
 698     vol->files = file->next;
 699
 700   FREE(file);
 701
 702   return result;
 703 }
 704
 705 /* High-Level Catalog Routines ============================================= */
 706
 707 /*
 708  * NAME:        hfs->stat()
 709  * DESCRIPTION: return catalog information for an arbitrary path
 710  */
 711 int hfs_stat(hfsvol *vol, const char *path, hfsdirent *ent)
 712 {
 713   CatDataRec data;
 714   unsigned long parid;
 715   char name[HFS_MAX_FLEN + 1];
 716
 717   if (getvol(&vol) == -1 ||
 718       v_resolve(&vol, path, &data, &parid, name, NULL) <= 0)
 719     goto fail;
 720
 721   r_unpackdirent(parid, name, &data, ent);
 722
 723   return 0;
 724
 725 fail:
 726   return -1;
 727 }
 728
 729 /*
 730  * NAME:        hfs->fstat()
 731  * DESCRIPTION: return catalog information for an open file
 732  */
 733 int hfs_fstat(hfsfile *file, hfsdirent *ent)
 734 {
 735   r_unpackdirent(file->parid, file->name, &file->cat, ent);
 736
 737   return 0;
 738 }
 739
 740 /*
 741  * NAME:        hfs->probe()
 742  * DESCRIPTION: return whether a HFS filesystem is present at the given offset
 743  */
 744 int hfs_probe(int fd, long long offset)
 745 {
 746   return v_probe(fd, offset);
 747 }