lib/libstand/hammerread.c

   1 /*
   2  * Copyright (c) 2008 The DragonFly Project.  All rights reserved.
   3  *
   4  * This code is derived from software contributed to The DragonFly Project
   5  * by Simon Schubert <corecode@fs.ei.tum.de>
   6  * and Matthew Dillon <dillon@backplane.com>
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  *
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in
  16  *    the documentation and/or other materials provided with the
  17  *    distribution.
  18  * 3. Neither the name of The DragonFly Project nor the names of its
  19  *    contributors may be used to endorse or promote products derived
  20  *    from this software without specific, prior written permission.
  21  *
  22  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  23  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  24  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  25  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
  26  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  27  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
  28  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  29  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  30  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  31  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  32  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  *
  35  * $DragonFly: src/lib/libstand/hammerread.c,v 1.2 2008/10/29 22:14:25 swildner Exp $
  36  */
  37
  38 /*
  39  * This file is being used by boot2 and libstand (loader).
  40  * Compile with -DTESTING to obtain a binary.
  41  */
  42
  43
  44 #if !defined(BOOT2) && !defined(TESTING)
  45 #define LIBSTAND        1
  46 #endif
  47
  48 #ifdef BOOT2
  49 #include "boot2.h"
  50 #else
  51 #include <sys/param.h>
  52 #include <stddef.h>
  53 #include <stdint.h>
  54 #endif
  55
  56 #ifdef TESTING
  57 #include <sys/fcntl.h>
  58 #include <sys/stat.h>
  59 #include <unistd.h>
  60 #include <err.h>
  61 #include <stdio.h>
  62 #include <stdlib.h>
  63 #include <string.h>
  64 #include <errno.h>
  65 #include <dirent.h>
  66 #endif
  67
  68 #ifdef LIBSTAND
  69 #include "stand.h"
  70 #endif
  71
  72 #include <vfs/hammer/hammer_disk.h>
  73
  74 #ifndef BOOT2
  75 struct blockentry {
  76         hammer_off_t    off;
  77         int             use;
  78         char            *data;
  79 };
  80
  81 #ifdef TESTING
  82 #define NUMCACHE        16
  83 #else
  84 #define NUMCACHE        6
  85 #endif
  86
  87 struct hfs {
  88 #ifdef TESTING
  89         int             fd;
  90 #else   // libstand
  91         struct open_file *f;
  92 #endif
  93         hammer_off_t    root;
  94         int64_t         buf_beg;
  95         int64_t         last_dir_ino;
  96         u_int8_t        last_dir_cap_flags;
  97         int             lru;
  98         struct blockentry cache[NUMCACHE];
  99 };
 100
 101 static void *
 102 hread(struct hfs *hfs, hammer_off_t off)
 103 {
 104         hammer_off_t boff = off & ~HAMMER_BUFMASK64;
 105
 106         boff &= HAMMER_OFF_LONG_MASK;
 107
 108         if (HAMMER_ZONE_DECODE(off) != HAMMER_ZONE_RAW_VOLUME_INDEX)
 109                 boff += hfs->buf_beg;
 110
 111         struct blockentry *be = NULL;
 112         for (int i = 0; i < NUMCACHE; i++) {
 113                 if (be == NULL || be->use > hfs->cache[i].use)
 114                         be = &hfs->cache[i];
 115                 if (hfs->cache[i].off == boff) {
 116                         be = &hfs->cache[i];
 117                         break;
 118                 }
 119         }
 120         if (be->off != boff) {
 121                 // Didn't find any match
 122                 be->off = boff;
 123 #ifdef TESTING
 124                 ssize_t res = pread(hfs->fd, be->data, HAMMER_BUFSIZE,
 125                                     boff & HAMMER_OFF_SHORT_MASK);
 126                 if (res != HAMMER_BUFSIZE)
 127                         err(1, "short read on off %llx", boff);
 128 #else   // libstand
 129                 size_t rlen;
 130                 int rv = hfs->f->f_dev->dv_strategy(hfs->f->f_devdata, F_READ,
 131                         boff >> DEV_BSHIFT, HAMMER_BUFSIZE,
 132                         be->data, &rlen);
 133                 if (rv || rlen != HAMMER_BUFSIZE)
 134                         return (NULL);
 135 #endif
 136         }
 137
 138         be->use = ++hfs->lru;
 139         return &be->data[off & HAMMER_BUFMASK];
 140 }
 141
 142 #else   /* BOOT2 */
 143
 144 struct hammer_dmadat {
 145         struct boot2_dmadat boot2;
 146         char            buf[HAMMER_BUFSIZE];
 147 };
 148
 149 #define fsdmadat        ((struct hammer_dmadat *)boot2_dmadat)
 150
 151 struct hfs {
 152         hammer_off_t    root;
 153         int64_t         last_dir_ino;
 154         u_int8_t        last_dir_cap_flags;
 155         int64_t         buf_beg;
 156 };
 157
 158 static void *
 159 hread(struct hfs *hfs, hammer_off_t off)
 160 {
 161         char *buf = fsdmadat->buf;
 162
 163         hammer_off_t boff = off & ~HAMMER_BUFMASK64;
 164         boff &= HAMMER_OFF_LONG_MASK;
 165         if (HAMMER_ZONE_DECODE(off) != HAMMER_ZONE_RAW_VOLUME_INDEX)
 166                 boff += hfs->buf_beg;
 167         boff &= HAMMER_OFF_SHORT_MASK;
 168         boff >>= DEV_BSHIFT;
 169         if (dskread(buf, boff, HAMMER_BUFSIZE >> DEV_BSHIFT))
 170                 return (NULL);
 171         return (&buf[off & HAMMER_BUFMASK]);
 172 }
 173
 174 static void
 175 bzero(void *buf, size_t size)
 176 {
 177         for (size_t i = 0; i < size; i++)
 178                 ((char *)buf)[i] = 0;
 179 }
 180
 181 static void
 182 bcopy(void *src, void *dst, size_t size)
 183 {
 184         memcpy(dst, src, size);
 185 }
 186
 187 static size_t
 188 strlen(const char *s)
 189 {
 190         size_t l = 0;
 191         for (; *s != 0; s++)
 192                 l++;
 193         return (l);
 194 }
 195
 196 static int
 197 memcmp(const void *a, const void *b, size_t len)
 198 {
 199         for (size_t p = 0; p < len; p++) {
 200                 int r = ((const char *)a)[p] - ((const char *)b)[p];
 201                 if (r != 0)
 202                         return (r);
 203         }
 204
 205         return (0);
 206 }
 207
 208 #endif
 209
 210 /*
 211  * (from hammer_btree.c)
 212  *
 213  * Compare two B-Tree elements, return -N, 0, or +N (e.g. similar to strcmp).
 214  *
 215  * Note that for this particular function a return value of -1, 0, or +1
 216  * can denote a match if create_tid is otherwise discounted.  A create_tid
 217  * of zero is considered to be 'infinity' in comparisons.
 218  *
 219  * See also hammer_rec_rb_compare() and hammer_rec_cmp() in hammer_object.c.
 220  */
 221 static int
 222 hammer_btree_cmp(hammer_base_elm_t key1, hammer_base_elm_t key2)
 223 {
 224         if (key1->localization < key2->localization)
 225                 return(-5);
 226         if (key1->localization > key2->localization)
 227                 return(5);
 228
 229         if (key1->obj_id < key2->obj_id)
 230                 return(-4);
 231         if (key1->obj_id > key2->obj_id)
 232                 return(4);
 233
 234         if (key1->rec_type < key2->rec_type)
 235                 return(-3);
 236         if (key1->rec_type > key2->rec_type)
 237                 return(3);
 238
 239         if (key1->key < key2->key)
 240                 return(-2);
 241         if (key1->key > key2->key)
 242                 return(2);
 243
 244         /*
 245          * A create_tid of zero indicates a record which is undeletable
 246          * and must be considered to have a value of positive infinity.
 247          */
 248         if (key1->create_tid == 0) {
 249                 if (key2->create_tid == 0)
 250                         return(0);
 251                 return(1);
 252         }
 253         if (key2->create_tid == 0)
 254                 return(-1);
 255         if (key1->create_tid < key2->create_tid)
 256                 return(-1);
 257         if (key1->create_tid > key2->create_tid)
 258                 return(1);
 259         return(0);
 260 }
 261
 262 /*
 263  * Heuristical search for the first element whos comparison is <= 1.  May
 264  * return an index whos compare result is > 1 but may only return an index
 265  * whos compare result is <= 1 if it is the first element with that result.
 266  */
 267 static int
 268 hammer_btree_search_node(hammer_base_elm_t elm, hammer_node_ondisk_t node)
 269 {
 270         int b;
 271         int s;
 272         int i;
 273         int r;
 274
 275         /*
 276          * Don't bother if the node does not have very many elements
 277          */
 278         b = 0;
 279         s = node->count;
 280         while (s - b > 4) {
 281                 i = b + (s - b) / 2;
 282                 r = hammer_btree_cmp(elm, &node->elms[i].leaf.base);
 283                 if (r <= 1) {
 284                         s = i;
 285                 } else {
 286                         b = i;
 287                 }
 288         }
 289         return(b);
 290 }
 291
 292 #if 0
 293 /*
 294  * (from hammer_subs.c)
 295  *
 296  * Return a namekey hash.   The 64 bit namekey hash consists of a 32 bit
 297  * crc in the MSB and 0 in the LSB.  The caller will use the low bits to
 298  * generate a unique key and will scan all entries with the same upper
 299  * 32 bits when issuing a lookup.
 300  *
 301  * We strip bit 63 in order to provide a positive key, this way a seek
 302  * offset of 0 will represent the base of the directory.
 303  *
 304  * This function can never return 0.  We use the MSB-0 space to synthesize
 305  * artificial directory entries such as "." and "..".
 306  */
 307 static int64_t
 308 hammer_directory_namekey(const void *name, int len)
 309 {
 310         int64_t key;
 311
 312         key = (int64_t)(crc32(name, len) & 0x7FFFFFFF) << 32;
 313         if (key == 0)
 314                 key |= 0x100000000LL;
 315         return(key);
 316 }
 317 #else
 318 static int64_t
 319 hammer_directory_namekey(const void *name __unused, int len __unused)
 320 {
 321         return (0);
 322 }
 323 #endif
 324
 325
 326 #ifndef BOOT2
 327 /*
 328  * Misc
 329  */
 330 static u_int32_t
 331 hammer_to_unix_xid(uuid_t *uuid)
 332 {
 333         return(*(u_int32_t *)&uuid->node[2]);
 334 }
 335
 336 static int
 337 hammer_get_dtype(u_int8_t obj_type)
 338 {
 339         switch(obj_type) {
 340         case HAMMER_OBJTYPE_DIRECTORY:
 341                 return(DT_DIR);
 342         case HAMMER_OBJTYPE_REGFILE:
 343                 return(DT_REG);
 344         case HAMMER_OBJTYPE_DBFILE:
 345                 return(DT_DBF);
 346         case HAMMER_OBJTYPE_FIFO:
 347                 return(DT_FIFO);
 348         case HAMMER_OBJTYPE_SOCKET:
 349                 return(DT_SOCK);
 350         case HAMMER_OBJTYPE_CDEV:
 351                 return(DT_CHR);
 352         case HAMMER_OBJTYPE_BDEV:
 353                 return(DT_BLK);
 354         case HAMMER_OBJTYPE_SOFTLINK:
 355                 return(DT_LNK);
 356         default:
 357                 return(DT_UNKNOWN);
 358         }
 359         /* not reached */
 360 }
 361
 362 static int
 363 hammer_get_mode(u_int8_t obj_type)
 364 {
 365         switch(obj_type) {
 366         case HAMMER_OBJTYPE_DIRECTORY:
 367                 return(S_IFDIR);
 368         case HAMMER_OBJTYPE_REGFILE:
 369                 return(S_IFREG);
 370         case HAMMER_OBJTYPE_DBFILE:
 371                 return(S_IFDB);
 372         case HAMMER_OBJTYPE_FIFO:
 373                 return(S_IFIFO);
 374         case HAMMER_OBJTYPE_SOCKET:
 375                 return(S_IFSOCK);
 376         case HAMMER_OBJTYPE_CDEV:
 377                 return(S_IFCHR);
 378         case HAMMER_OBJTYPE_BDEV:
 379                 return(S_IFBLK);
 380         case HAMMER_OBJTYPE_SOFTLINK:
 381                 return(S_IFLNK);
 382         default:
 383                 return(0);
 384         }
 385         /* not reached */
 386 }
 387
 388 #if DEBUG > 1
 389 static void
 390 hprintb(hammer_base_elm_t e)
 391 {
 392         printf("%d/", e->localization);
 393         if (e->obj_id >> 32 != 0)
 394                 printf("%lx%08lx",
 395                        (long)(e->obj_id >> 32),
 396                        (long)(e->obj_id & 0xffffffff));
 397         else
 398                 printf("%lx", (long)e->obj_id);
 399         printf("/%d/", e->rec_type);
 400         if (e->key >> 32 != 0)
 401                 printf("%lx%08lx",
 402                        (long)(e->key >> 32),
 403                        (long)(e->key & 0xffffffff));
 404         else
 405                 printf("%lx", (long)e->key);
 406 #ifdef TESTING
 407         printf("/%llx/%llx", e->create_tid, e->delete_tid);
 408 #endif
 409 }
 410 #endif /* DEBUG > 1 */
 411 #endif /* !BOOT2 */
 412
 413 static hammer_btree_leaf_elm_t
 414 hfind(struct hfs *hfs, hammer_base_elm_t key, hammer_base_elm_t end)
 415 {
 416 #if DEBUG > 1
 417         printf("searching for ");
 418         hprintb(key);
 419         printf(" end ");
 420         hprintb(end);
 421         printf("\n");
 422 #endif
 423
 424         int n;
 425         int r;
 426         struct hammer_base_elm search = *key;
 427         struct hammer_base_elm backtrack;
 428         hammer_off_t nodeoff = hfs->root;
 429         hammer_node_ondisk_t node;
 430         hammer_btree_elm_t e = NULL;
 431         int internal;
 432
 433 loop:
 434         node = hread(hfs, nodeoff);
 435         if (node == NULL)
 436                 return (NULL);
 437         internal = node->type == HAMMER_BTREE_TYPE_INTERNAL;
 438
 439 #if DEBUG > 3
 440         for (int i = 0; i < node->count; i++) {
 441                 printf("E: ");
 442                 hprintb(&node->elms[i].base);
 443                 printf("\n");
 444         }
 445         if (internal) {
 446                 printf("B: ");
 447                 hprintb(&node->elms[node->count].base);
 448                 printf("\n");
 449         }
 450 #endif
 451
 452         n = hammer_btree_search_node(&search, node);
 453
 454         // In internal nodes, we cover the right boundary as well.
 455         // If we hit it, we'll backtrack.
 456         for (; n < node->count + internal; n++) {
 457                 e = &node->elms[n];
 458                 r = hammer_btree_cmp(&search, &e->base);
 459
 460                 if (r < 0)
 461                         break;
 462         }
 463
 464         // unless we stopped right on the left side, we need to back off a bit
 465         if (n > 0)
 466                 e = &node->elms[--n];
 467
 468 #if DEBUG > 2
 469         printf("  found: ");
 470         hprintb(&e->base);
 471         printf("\n");
 472 #endif
 473
 474         if (internal) {
 475                 // If we hit the right boundary, backtrack to
 476                 // the next higher level.
 477                 if (n == node->count)
 478                         goto backtrack;
 479                 nodeoff = e->internal.subtree_offset;
 480                 backtrack = (e+1)->base;
 481                 goto loop;
 482         }
 483
 484         r = hammer_btree_cmp(key, &e->base);
 485         // If we're more off than the createtid, take the next elem
 486         if (r > 1) {
 487                 e++;
 488                 n++;
 489         }
 490
 491         // Skip deleted elements
 492         while (n < node->count && e->base.delete_tid != 0) {
 493                 e++;
 494                 n++;
 495         }
 496
 497         // In the unfortunate event when there is no next
 498         // element in this node, we repeat the search with
 499         // a key beyond the right boundary
 500         if (n == node->count) {
 501 backtrack:
 502                 search = backtrack;
 503                 nodeoff = hfs->root;
 504
 505 #if DEBUG > 2
 506                 printf("hit right boundary (%d), resetting search to ",
 507                        node->count);
 508                 hprintb(&search);
 509                 printf("\n");
 510 #endif
 511                 goto loop;
 512         }
 513
 514 #if DEBUG > 1
 515         printf("  result: ");
 516         hprintb(&e->base);
 517         printf("\n");
 518 #endif
 519
 520         if (end != NULL)
 521                 if (hammer_btree_cmp(end, &e->base) < -1)
 522                         goto fail;
 523
 524         return (&e->leaf);
 525
 526 fail:
 527 #if DEBUG > 1
 528         printf("  fail.\n");
 529 #endif
 530         return (NULL);
 531 }
 532
 533 /*
 534  * Returns the directory entry localization field based on the directory
 535  * inode's capabilities.
 536  */
 537 static u_int32_t
 538 hdirlocalization(struct hfs *hfs, ino_t ino)
 539 {
 540         struct hammer_base_elm key;
 541
 542         if (ino != hfs->last_dir_ino) {
 543                 bzero(&key, sizeof(key));
 544                 key.obj_id = ino;
 545                 key.localization = HAMMER_LOCALIZE_INODE;
 546                 key.rec_type = HAMMER_RECTYPE_INODE;
 547                 hammer_btree_leaf_elm_t e;
 548                 hammer_data_ondisk_t ed;
 549
 550                 e = hfind(hfs, &key, &key);
 551                 if (e) {
 552                         ed = hread(hfs, e->data_offset);
 553                         if (ed) {
 554                                 hfs->last_dir_ino = ino;
 555                                 hfs->last_dir_cap_flags = ed->inode.cap_flags;
 556                         } else {
 557                                 printf("hdirlocal: no inode data for %llx\n",
 558                                         (long long)ino);
 559                         }
 560                 } else {
 561                         printf("hdirlocal: no inode entry for %llx\n",
 562                                 (long long)ino);
 563                 }
 564         }
 565         if (hfs->last_dir_cap_flags & HAMMER_INODE_CAP_DIR_LOCAL_INO)
 566                 return(HAMMER_LOCALIZE_INODE);
 567         else
 568                 return(HAMMER_LOCALIZE_MISC);
 569 }
 570
 571 #ifndef BOOT2
 572 static int
 573 hreaddir(struct hfs *hfs, ino_t ino, int64_t *off, struct dirent *de)
 574 {
 575         struct hammer_base_elm key, end;
 576
 577 #if DEBUG > 2
 578         printf("%s(%llx, %lld)\n", __FUNCTION__, (long long)ino, *off);
 579 #endif
 580
 581         bzero(&key, sizeof(key));
 582         key.obj_id = ino;
 583         key.localization = hdirlocalization(hfs, ino);
 584         key.rec_type = HAMMER_RECTYPE_DIRENTRY;
 585         key.key = *off;
 586
 587         end = key;
 588         end.key = HAMMER_MAX_KEY;
 589
 590         hammer_btree_leaf_elm_t e;
 591
 592         e = hfind(hfs, &key, &end);
 593         if (e == NULL) {
 594                 errno = ENOENT;
 595                 return (-1);
 596         }
 597
 598         *off = e->base.key + 1;         // remember next pos
 599
 600         de->d_namlen = e->data_len - HAMMER_ENTRY_NAME_OFF;
 601         de->d_type = hammer_get_dtype(e->base.obj_type);
 602         hammer_data_ondisk_t ed = hread(hfs, e->data_offset);
 603         if (ed == NULL)
 604                 return (-1);
 605         de->d_ino = ed->entry.obj_id;
 606         bcopy(ed->entry.name, de->d_name, de->d_namlen);
 607         de->d_name[de->d_namlen] = 0;
 608
 609         return (0);
 610 }
 611 #endif
 612
 613 static ino_t
 614 hresolve(struct hfs *hfs, ino_t dirino, const char *name)
 615 {
 616         struct hammer_base_elm key, end;
 617         size_t namel = strlen(name);
 618
 619 #if DEBUG > 2
 620         printf("%s(%llx, %s)\n", __FUNCTION__, (long long)dirino, name);
 621 #endif
 622
 623         bzero(&key, sizeof(key));
 624         key.obj_id = dirino;
 625         key.localization = hdirlocalization(hfs, dirino);
 626         key.key = hammer_directory_namekey(name, namel);
 627         key.rec_type = HAMMER_RECTYPE_DIRENTRY;
 628         end = key;
 629         end.key = HAMMER_MAX_KEY;
 630
 631         hammer_btree_leaf_elm_t e;
 632         while ((e = hfind(hfs, &key, &end)) != NULL) {
 633                 key.key = e->base.key + 1;
 634
 635                 size_t elen = e->data_len - HAMMER_ENTRY_NAME_OFF;
 636                 hammer_data_ondisk_t ed = hread(hfs, e->data_offset);
 637                 if (ed == NULL)
 638                         return (-1);
 639 #ifdef BOOT2
 640                 if (ls) {
 641                         for (int i = 0; i < elen; i++)
 642                                 putchar(ed->entry.name[i]);
 643                         putchar(' ');
 644                         ls = 2;
 645                         continue;
 646                 }
 647 #endif
 648                 if (elen == namel && memcmp(ed->entry.name, name, MIN(elen, namel)) == 0)
 649                         return (ed->entry.obj_id);
 650         }
 651
 652 #if BOOT2
 653         if (ls == 2)
 654                 printf("\n");
 655 #endif
 656
 657         return -1;
 658 }
 659
 660 static ino_t
 661 hlookup(struct hfs *hfs, const char *path)
 662 {
 663 #if DEBUG > 2
 664         printf("%s(%s)\n", __FUNCTION__, path);
 665 #endif
 666
 667 #ifdef BOOT2
 668         ls = 0;
 669 #endif
 670         ino_t ino = 1;
 671         do {
 672                 char name[MAXPATHLEN + 1];
 673                 while (*path == '/')
 674                         path++;
 675                 if (*path == 0)
 676                         break;
 677                 for (char *n = name; *path != 0 && *path != '/'; path++, n++) {
 678                         n[0] = *path;
 679                         n[1] = 0;
 680                 }
 681
 682 #ifdef BOOT2
 683                 // A single ? means "list"
 684                 if (name[0] == '?' && name[1] == 0)
 685                         ls = 1;
 686 #endif
 687
 688                 ino = hresolve(hfs, ino, name);
 689         } while (ino != (ino_t)-1 && *path != 0);
 690
 691         return (ino);
 692 }
 693
 694
 695 #ifndef BOOT2
 696 static int
 697 hstat(struct hfs *hfs, ino_t ino, struct stat* st)
 698 {
 699         struct hammer_base_elm key;
 700
 701 #if DEBUG > 2
 702         printf("%s(%llx)\n", __FUNCTION__, (long long)ino);
 703 #endif
 704
 705         bzero(&key, sizeof(key));
 706         key.obj_id = ino;
 707         key.localization = HAMMER_LOCALIZE_INODE;
 708         key.rec_type = HAMMER_RECTYPE_INODE;
 709
 710         hammer_btree_leaf_elm_t e = hfind(hfs, &key, &key);
 711         if (e == NULL) {
 712 #ifndef BOOT2
 713                 errno = ENOENT;
 714 #endif
 715                 return -1;
 716         }
 717
 718         hammer_data_ondisk_t ed = hread(hfs, e->data_offset);
 719         if (ed == NULL)
 720                 return (-1);
 721
 722         st->st_mode = ed->inode.mode | hammer_get_mode(ed->inode.obj_type);
 723         st->st_uid = hammer_to_unix_xid(&ed->inode.uid);
 724         st->st_gid = hammer_to_unix_xid(&ed->inode.gid);
 725         st->st_size = ed->inode.size;
 726
 727         return (0);
 728 }
 729 #endif
 730
 731 static ssize_t
 732 hreadf(struct hfs *hfs, ino_t ino, int64_t off, int64_t len, char *buf)
 733 {
 734         int64_t startoff = off;
 735         struct hammer_base_elm key, end;
 736
 737         bzero(&key, sizeof(key));
 738         key.obj_id = ino;
 739         key.localization = HAMMER_LOCALIZE_MISC;
 740         key.rec_type = HAMMER_RECTYPE_DATA;
 741         end = key;
 742         end.key = HAMMER_MAX_KEY;
 743
 744         while (len > 0) {
 745                 key.key = off + 1;
 746                 hammer_btree_leaf_elm_t e = hfind(hfs, &key, &end);
 747                 int64_t dlen;
 748
 749                 if (e == NULL || off > e->base.key) {
 750                         bzero(buf, len);
 751                         off += len;
 752                         len = 0;
 753                         break;
 754                 }
 755
 756                 int64_t doff = e->base.key - e->data_len;
 757                 if (off < doff) {
 758                         // sparse file, beginning
 759                         dlen = doff - off;
 760                         dlen = MIN(dlen, len);
 761                         bzero(buf, dlen);
 762                 } else {
 763                         int64_t boff = off - doff;
 764                         hammer_off_t roff = e->data_offset;
 765
 766                         dlen = e->data_len;
 767                         dlen -= boff;
 768                         dlen = MIN(dlen, len);
 769
 770                         while (boff >= HAMMER_BUFSIZE) {
 771                                 boff -= HAMMER_BUFSIZE;
 772                                 roff += HAMMER_BUFSIZE;
 773                         }
 774
 775                         /*
 776                          * boff - relative offset in disk buffer (not aligned)
 777                          * roff - base offset of disk buffer     (not aligned)
 778                          * dlen - amount of data we think we can copy
 779                          *
 780                          * hread only reads 16K aligned buffers, check for
 781                          * a length overflow and truncate dlen appropriately.
 782                          */
 783                         if ((roff & ~HAMMER_BUFMASK64) != ((roff + boff + dlen - 1) & ~HAMMER_BUFMASK64))
 784                                 dlen = HAMMER_BUFSIZE - ((boff + roff) & HAMMER_BUFMASK);
 785                         char *data = hread(hfs, roff);
 786                         if (data == NULL)
 787                                 return (-1);
 788                         bcopy(data + boff, buf, dlen);
 789                 }
 790
 791                 buf += dlen;
 792                 off += dlen;
 793                 len -= dlen;
 794         }
 795
 796         return (off - startoff);
 797 }
 798
 799 #ifdef BOOT2
 800 struct hfs hfs;
 801
 802 static int
 803 boot2_hammer_init(void)
 804 {
 805         hammer_volume_ondisk_t volhead;
 806
 807         volhead = hread(&hfs, HAMMER_ZONE_ENCODE(1, 0));
 808         if (volhead == NULL)
 809                 return (-1);
 810         if (volhead->vol_signature != HAMMER_FSBUF_VOLUME)
 811                 return (-1);
 812         hfs.root = volhead->vol0_btree_root;
 813         hfs.buf_beg = volhead->vol_buf_beg;
 814         return (0);
 815 }
 816
 817 static boot2_ino_t
 818 boot2_hammer_lookup(const char *path)
 819 {
 820         ino_t ino = hlookup(&hfs, path);
 821
 822         if (ino == -1)
 823                 ino = 0;
 824
 825         fs_off = 0;
 826
 827         return (ino);
 828 }
 829
 830 static ssize_t
 831 boot2_hammer_read(boot2_ino_t ino, void *buf, size_t len)
 832 {
 833         ssize_t rlen = hreadf(&hfs, ino, fs_off, len, buf);
 834         if (rlen != -1)
 835                 fs_off += rlen;
 836         return (rlen);
 837 }
 838
 839 const struct boot2_fsapi boot2_hammer_api = {
 840         .fsinit = boot2_hammer_init,
 841         .fslookup = boot2_hammer_lookup,
 842         .fsread = boot2_hammer_read
 843 };
 844
 845 #endif
 846
 847 #ifndef BOOT2
 848 static int
 849 hinit(struct hfs *hfs)
 850 {
 851 #if DEBUG
 852         printf("hinit\n");
 853 #endif
 854         for (int i = 0; i < NUMCACHE; i++) {
 855                 hfs->cache[i].data = malloc(HAMMER_BUFSIZE);
 856                 hfs->cache[i].off = -1; // invalid
 857                 hfs->cache[i].use = 0;
 858
 859 #if DEBUG
 860                 if (hfs->cache[i].data == NULL)
 861                         printf("malloc failed\n");
 862 #endif
 863         }
 864         hfs->lru = 0;
 865         hfs->last_dir_ino = -1;
 866
 867         hammer_volume_ondisk_t volhead = hread(hfs, HAMMER_ZONE_ENCODE(1, 0));
 868
 869 #ifdef TESTING
 870         if (volhead) {
 871                 printf("signature: %svalid\n",
 872                        volhead->vol_signature != HAMMER_FSBUF_VOLUME ?
 873                                 "in" :
 874                                 "");
 875                 printf("name: %s\n", volhead->vol_name);
 876         }
 877 #endif
 878
 879         if (volhead == NULL || volhead->vol_signature != HAMMER_FSBUF_VOLUME) {
 880                 for (int i = 0; i < NUMCACHE; i++) {
 881                         free(hfs->cache[i].data);
 882                         hfs->cache[i].data = NULL;
 883                 }
 884                 errno = ENODEV;
 885                 return (-1);
 886         }
 887
 888         hfs->root = volhead->vol0_btree_root;
 889         hfs->buf_beg = volhead->vol_buf_beg;
 890
 891         return (0);
 892 }
 893
 894 static void
 895 hclose(struct hfs *hfs)
 896 {
 897 #if DEBUG
 898         printf("hclose\n");
 899 #endif
 900         for (int i = 0; i < NUMCACHE; i++) {
 901                 if (hfs->cache[i].data) {
 902                         free(hfs->cache[i].data);
 903                         hfs->cache[i].data = NULL;
 904                 }
 905         }
 906 }
 907 #endif
 908
 909 #ifdef LIBSTAND
 910 struct hfile {
 911         struct hfs      hfs;
 912         ino_t           ino;
 913         int64_t         fsize;
 914 };
 915
 916 static int
 917 hammer_open(const char *path, struct open_file *f)
 918 {
 919         struct hfile *hf = malloc(sizeof(*hf));
 920
 921         bzero(hf, sizeof(*hf));
 922         f->f_fsdata = hf;
 923         hf->hfs.f = f;
 924         f->f_offset = 0;
 925
 926         int rv = hinit(&hf->hfs);
 927         if (rv) {
 928                 f->f_fsdata = NULL;
 929                 free(hf);
 930                 return (rv);
 931         }
 932
 933 #if DEBUG
 934         printf("hammer_open %s %p %ld\n", path, f);
 935 #endif
 936
 937         hf->ino = hlookup(&hf->hfs, path);
 938         if (hf->ino == -1)
 939                 goto fail;
 940
 941         struct stat st;
 942         if (hstat(&hf->hfs, hf->ino, &st) == -1)
 943                 goto fail;
 944         hf->fsize = st.st_size;
 945
 946 #if DEBUG
 947         printf("        %ld\n", (long)hf->fsize);
 948 #endif
 949
 950         return (0);
 951
 952 fail:
 953 #if DEBUG
 954         printf("hammer_open fail\n");
 955 #endif
 956         f->f_fsdata = NULL;
 957         hclose(&hf->hfs);
 958         free(hf);
 959         return (ENOENT);
 960 }
 961
 962 static int
 963 hammer_close(struct open_file *f)
 964 {
 965         struct hfile *hf = f->f_fsdata;
 966
 967         f->f_fsdata = NULL;
 968         if (hf) {
 969             hclose(&hf->hfs);
 970             free(hf);
 971         }
 972         return (0);
 973 }
 974
 975 static int
 976 hammer_read(struct open_file *f, void *buf, size_t len, size_t *resid)
 977 {
 978         struct hfile *hf = f->f_fsdata;
 979
 980 #if DEBUG
 981         printf("hammer_read %p %ld %ld\n", f, f->f_offset, len);
 982 #endif
 983
 984         if (f->f_offset >= hf->fsize)
 985                 return (EINVAL);
 986
 987         size_t maxlen = len;
 988         if (f->f_offset + len > hf->fsize)
 989                 maxlen = hf->fsize - f->f_offset;
 990
 991         ssize_t rlen = hreadf(&hf->hfs, hf->ino, f->f_offset, maxlen, buf);
 992         if (rlen == -1)
 993                 return (EINVAL);
 994
 995         f->f_offset += rlen;
 996
 997         *resid = len - rlen;
 998         return (0);
 999 }
1000
1001 static off_t
1002 hammer_seek(struct open_file *f, off_t offset, int whence)
1003 {
1004         struct hfile *hf = f->f_fsdata;
1005
1006         switch (whence) {
1007         case SEEK_SET:
1008                 f->f_offset = offset;
1009                 break;
1010         case SEEK_CUR:
1011                 f->f_offset += offset;
1012                 break;
1013         case SEEK_END:
1014                 f->f_offset = hf->fsize - offset;
1015                 break;
1016         default:
1017                 return (-1);
1018         }
1019         return (f->f_offset);
1020 }
1021
1022 static int
1023 hammer_stat(struct open_file *f, struct stat *st)
1024 {
1025         struct hfile *hf = f->f_fsdata;
1026
1027         return (hstat(&hf->hfs, hf->ino, st));
1028 }
1029
1030 static int
1031 hammer_readdir(struct open_file *f, struct dirent *d)
1032 {
1033         struct hfile *hf = f->f_fsdata;
1034
1035         int64_t off = f->f_offset;
1036         int rv = hreaddir(&hf->hfs, hf->ino, &off, d);
1037         f->f_offset = off;
1038         return (rv);
1039 }
1040
1041 // libstand
1042 struct fs_ops hammer_fsops = {
1043         "hammer",
1044         hammer_open,
1045         hammer_close,
1046         hammer_read,
1047         null_write,
1048         hammer_seek,
1049         hammer_stat,
1050         hammer_readdir
1051 };
1052 #endif  // LIBSTAND
1053
1054 #ifdef TESTING
1055 int
1056 main(int argc, char **argv)
1057 {
1058         if (argc < 2) {
1059                 fprintf(stderr, "usage: hammerread <dev>\n");
1060                 return (1);
1061         }
1062
1063         struct hfs hfs;
1064         hfs.fd = open(argv[1], O_RDONLY);
1065         if (hfs.fd == -1)
1066                 err(1, "unable to open %s", argv[1]);
1067
1068         if (hinit(&hfs) == -1)
1069                 err(1, "invalid hammerfs");
1070
1071         for (int i = 2; i < argc; i++) {
1072                 ino_t ino = hlookup(&hfs, argv[i]);
1073                 if (ino == (ino_t)-1) {
1074                         warn("hlookup %s", argv[i]);
1075                         continue;
1076                 }
1077
1078                 struct stat st;
1079                 if (hstat(&hfs, ino, &st)) {
1080                         warn("hstat %s", argv[i]);
1081                         continue;
1082                 }
1083
1084                 printf("%s %d/%d %o %lld\n",
1085                        argv[i],
1086                        st.st_uid, st.st_gid,
1087                        st.st_mode, st.st_size);
1088
1089                 if (S_ISDIR(st.st_mode)) {
1090                         int64_t off = 0;
1091                         struct dirent de;
1092                         while (hreaddir(&hfs, ino, &off, &de) == 0) {
1093                                 printf("%s %d %llx\n",
1094                                        de.d_name, de.d_type, de.d_ino);
1095                         }
1096                 } else if (S_ISREG(st.st_mode)) {
1097                         char *buf = malloc(100000);
1098                         int64_t off = 0;
1099                         while (off < st.st_size) {
1100                                 int64_t len = MIN(100000, st.st_size - off);
1101                                 int64_t rl = hreadf(&hfs, ino, off, len, buf);
1102                                 fwrite(buf, rl, 1, stdout);
1103                                 off += rl;
1104                         }
1105                         free(buf);
1106                 }
1107         }
1108
1109         return 0;
1110 }
1111 #endif