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 1.1 2008/09/13 11:38:58 corecode 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 #include <sys/param.h>
  49
  50 #include <stddef.h>
  51 #include <stdint.h>
  52
  53 #ifdef TESTING
  54 #include <sys/fcntl.h>
  55 #include <sys/stat.h>
  56 #include <unistd.h>
  57 #include <err.h>
  58 #include <stdio.h>
  59 #include <stdlib.h>
  60 #include <string.h>
  61 #include <errno.h>
  62 #include <dirent.h>
  63 #endif
  64
  65 #ifdef LIBSTAND
  66 #include "stand.h"
  67 #endif
  68
  69 #include <vfs/hammer/hammer_disk.h>
  70
  71 #ifndef BOOT2
  72 struct blockentry {
  73         hammer_off_t    off;
  74         int             use;
  75         char            *data;
  76 };
  77
  78 #ifdef TESTING
  79 #define NUMCACHE        16
  80 #else
  81 #define NUMCACHE        6
  82 #endif
  83
  84 struct hfs {
  85 #ifdef TESTING
  86         int             fd;
  87 #else   // libstand
  88         struct open_file *f;
  89 #endif
  90         hammer_off_t    root;
  91         int64_t         buf_beg;
  92         int             lru;
  93         struct blockentry cache[NUMCACHE];
  94 };
  95
  96 static void *
  97 hread(struct hfs *hfs, hammer_off_t off)
  98 {
  99         hammer_off_t boff = off & ~HAMMER_BUFMASK;
 100
 101         boff &= HAMMER_OFF_LONG_MASK;
 102
 103         if (HAMMER_ZONE_DECODE(off) != HAMMER_ZONE_RAW_VOLUME_INDEX)
 104                 boff += hfs->buf_beg;
 105
 106         struct blockentry *be = NULL;
 107         for (int i = 0; i < NUMCACHE; i++) {
 108                 if (be == NULL || be->use > hfs->cache[i].use)
 109                         be = &hfs->cache[i];
 110                 if (hfs->cache[i].off == boff) {
 111                         be = &hfs->cache[i];
 112                         break;
 113                 }
 114         }
 115         if (be->off != boff) {
 116                 // Didn't find any match
 117                 be->off = boff;
 118 #ifdef TESTING
 119                 ssize_t res = pread(hfs->fd, be->data, HAMMER_BUFSIZE,
 120                                     boff & HAMMER_OFF_SHORT_MASK);
 121                 if (res != HAMMER_BUFSIZE)
 122                         err(1, "short read on off %llx", boff);
 123 #else   // libstand
 124                 size_t rlen;
 125                 int rv = hfs->f->f_dev->dv_strategy(hfs->f->f_devdata, F_READ,
 126                         boff >> DEV_BSHIFT, HAMMER_BUFSIZE,
 127                         be->data, &rlen);
 128                 if (rv || rlen != HAMMER_BUFSIZE)
 129                         return (NULL);
 130 #endif
 131         }
 132
 133         be->use = ++hfs->lru;
 134         return &be->data[off & HAMMER_BUFMASK];
 135 }
 136
 137 #else   /* BOOT2 */
 138
 139 struct dmadat {
 140         char            secbuf[DEV_BSIZE];
 141         char            buf[HAMMER_BUFSIZE];
 142 };
 143
 144 static struct dmadat *dmadat;
 145
 146 struct hfs {
 147         hammer_off_t    root;
 148         int64_t         buf_beg;
 149 };
 150
 151 static void *
 152 hread(struct hfs *hfs, hammer_off_t off)
 153 {
 154         char *buf = dmadat->buf;
 155
 156         hammer_off_t boff = off & ~HAMMER_BUFMASK;
 157         boff &= HAMMER_OFF_LONG_MASK;
 158         if (HAMMER_ZONE_DECODE(off) != HAMMER_ZONE_RAW_VOLUME_INDEX)
 159                 boff += hfs->buf_beg;
 160         boff &= HAMMER_OFF_SHORT_MASK;
 161         boff >>= DEV_BSHIFT;
 162         if (dskread(buf, boff, HAMMER_BUFSIZE >> DEV_BSHIFT))
 163                 return (NULL);
 164         return (&buf[off & HAMMER_BUFMASK]);
 165 }
 166
 167 static void
 168 bzero(void *buf, size_t size)
 169 {
 170         for (size_t i = 0; i < size; i++)
 171                 ((char *)buf)[i] = 0;
 172 }
 173
 174 static void
 175 bcopy(void *src, void *dst, size_t size)
 176 {
 177         memcpy(dst, src, size);
 178 }
 179
 180 static size_t
 181 strlen(const char *s)
 182 {
 183         size_t l = 0;
 184         for (; *s != 0; s++)
 185                 l++;
 186         return (l);
 187 }
 188
 189 static int
 190 memcmp(const void *a, const void *b, size_t len)
 191 {
 192         for (size_t p = 0; p < len; p++) {
 193                 int r = ((const char *)a)[p] - ((const char *)b)[p];
 194                 if (r != 0)
 195                         return (r);
 196         }
 197
 198         return (0);
 199 }
 200
 201 #endif
 202
 203 /*
 204  * (from hammer_btree.c)
 205  *
 206  * Compare two B-Tree elements, return -N, 0, or +N (e.g. similar to strcmp).
 207  *
 208  * Note that for this particular function a return value of -1, 0, or +1
 209  * can denote a match if create_tid is otherwise discounted.  A create_tid
 210  * of zero is considered to be 'infinity' in comparisons.
 211  *
 212  * See also hammer_rec_rb_compare() and hammer_rec_cmp() in hammer_object.c.
 213  */
 214 static int
 215 hammer_btree_cmp(hammer_base_elm_t key1, hammer_base_elm_t key2)
 216 {
 217         if (key1->localization < key2->localization)
 218                 return(-5);
 219         if (key1->localization > key2->localization)
 220                 return(5);
 221
 222         if (key1->obj_id < key2->obj_id)
 223                 return(-4);
 224         if (key1->obj_id > key2->obj_id)
 225                 return(4);
 226
 227         if (key1->rec_type < key2->rec_type)
 228                 return(-3);
 229         if (key1->rec_type > key2->rec_type)
 230                 return(3);
 231
 232         if (key1->key < key2->key)
 233                 return(-2);
 234         if (key1->key > key2->key)
 235                 return(2);
 236
 237         /*
 238          * A create_tid of zero indicates a record which is undeletable
 239          * and must be considered to have a value of positive infinity.
 240          */
 241         if (key1->create_tid == 0) {
 242                 if (key2->create_tid == 0)
 243                         return(0);
 244                 return(1);
 245         }
 246         if (key2->create_tid == 0)
 247                 return(-1);
 248         if (key1->create_tid < key2->create_tid)
 249                 return(-1);
 250         if (key1->create_tid > key2->create_tid)
 251                 return(1);
 252         return(0);
 253 }
 254
 255 /*
 256  * Heuristical search for the first element whos comparison is <= 1.  May
 257  * return an index whos compare result is > 1 but may only return an index
 258  * whos compare result is <= 1 if it is the first element with that result.
 259  */
 260 static int
 261 hammer_btree_search_node(hammer_base_elm_t elm, hammer_node_ondisk_t node)
 262 {
 263         int b;
 264         int s;
 265         int i;
 266         int r;
 267
 268         /*
 269          * Don't bother if the node does not have very many elements
 270          */
 271         b = 0;
 272         s = node->count;
 273         while (s - b > 4) {
 274                 i = b + (s - b) / 2;
 275                 r = hammer_btree_cmp(elm, &node->elms[i].leaf.base);
 276                 if (r <= 1) {
 277                         s = i;
 278                 } else {
 279                         b = i;
 280                 }
 281         }
 282         return(b);
 283 }
 284
 285 #if 0
 286 /*
 287  * (from hammer_subs.c)
 288  *
 289  * Return a namekey hash.   The 64 bit namekey hash consists of a 32 bit
 290  * crc in the MSB and 0 in the LSB.  The caller will use the low bits to
 291  * generate a unique key and will scan all entries with the same upper
 292  * 32 bits when issuing a lookup.
 293  *
 294  * We strip bit 63 in order to provide a positive key, this way a seek
 295  * offset of 0 will represent the base of the directory.
 296  *
 297  * This function can never return 0.  We use the MSB-0 space to synthesize
 298  * artificial directory entries such as "." and "..".
 299  */
 300 static int64_t
 301 hammer_directory_namekey(const void *name, int len)
 302 {
 303         int64_t key;
 304
 305         key = (int64_t)(crc32(name, len) & 0x7FFFFFFF) << 32;
 306         if (key == 0)
 307                 key |= 0x100000000LL;
 308         return(key);
 309 }
 310 #else
 311 static int64_t
 312 hammer_directory_namekey(const void *name __unused, int len __unused)
 313 {
 314         return (0);
 315 }
 316 #endif
 317
 318
 319 #ifndef BOOT2
 320 /*
 321  * Misc
 322  */
 323 static u_int32_t
 324 hammer_to_unix_xid(uuid_t *uuid)
 325 {
 326         return(*(u_int32_t *)&uuid->node[2]);
 327 }
 328
 329 static int
 330 hammer_get_dtype(u_int8_t obj_type)
 331 {
 332         switch(obj_type) {
 333         case HAMMER_OBJTYPE_DIRECTORY:
 334                 return(DT_DIR);
 335         case HAMMER_OBJTYPE_REGFILE:
 336                 return(DT_REG);
 337         case HAMMER_OBJTYPE_DBFILE:
 338                 return(DT_DBF);
 339         case HAMMER_OBJTYPE_FIFO:
 340                 return(DT_FIFO);
 341         case HAMMER_OBJTYPE_SOCKET:
 342                 return(DT_SOCK);
 343         case HAMMER_OBJTYPE_CDEV:
 344                 return(DT_CHR);
 345         case HAMMER_OBJTYPE_BDEV:
 346                 return(DT_BLK);
 347         case HAMMER_OBJTYPE_SOFTLINK:
 348                 return(DT_LNK);
 349         default:
 350                 return(DT_UNKNOWN);
 351         }
 352         /* not reached */
 353 }
 354
 355 static int
 356 hammer_get_mode(u_int8_t obj_type)
 357 {
 358         switch(obj_type) {
 359         case HAMMER_OBJTYPE_DIRECTORY:
 360                 return(S_IFDIR);
 361         case HAMMER_OBJTYPE_REGFILE:
 362                 return(S_IFREG);
 363         case HAMMER_OBJTYPE_DBFILE:
 364                 return(S_IFDB);
 365         case HAMMER_OBJTYPE_FIFO:
 366                 return(S_IFIFO);
 367         case HAMMER_OBJTYPE_SOCKET:
 368                 return(S_IFSOCK);
 369         case HAMMER_OBJTYPE_CDEV:
 370                 return(S_IFCHR);
 371         case HAMMER_OBJTYPE_BDEV:
 372                 return(S_IFBLK);
 373         case HAMMER_OBJTYPE_SOFTLINK:
 374                 return(S_IFLNK);
 375         default:
 376                 return(0);
 377         }
 378         /* not reached */
 379 }
 380
 381 static void
 382 hprintb(hammer_base_elm_t e)
 383 {
 384         printf("%d/", e->localization);
 385         if (e->obj_id >> 32 != 0)
 386                 printf("%lx%08lx",
 387                        (long)(e->obj_id >> 32),
 388                        (long)(e->obj_id & 0xffffffff));
 389         else
 390                 printf("%lx", (long)e->obj_id);
 391         printf("/%d/", e->rec_type);
 392         if (e->key >> 32 != 0)
 393                 printf("%lx%08lx",
 394                        (long)(e->key >> 32),
 395                        (long)(e->key & 0xffffffff));
 396         else
 397                 printf("%lx", (long)e->key);
 398 #ifdef TESTING
 399         printf("/%llx/%llx", e->create_tid, e->delete_tid);
 400 #endif
 401 }
 402 #endif
 403
 404 static hammer_btree_leaf_elm_t
 405 hfind(struct hfs *hfs, hammer_base_elm_t key, hammer_base_elm_t end)
 406 {
 407 #if DEBUG > 1
 408         printf("searching for ");
 409         hprintb(key);
 410         printf("\n");
 411 #endif
 412
 413         int n;
 414         int r;
 415         struct hammer_base_elm search = *key;
 416         struct hammer_base_elm backtrack;
 417         hammer_off_t nodeoff = hfs->root;
 418         hammer_node_ondisk_t node;
 419         hammer_btree_elm_t e;
 420
 421 loop:
 422         node = hread(hfs, nodeoff);
 423         if (node == NULL)
 424                 return (NULL);
 425
 426 #if 0
 427         for (int i = 0; i < node->count; i++) {
 428                 printf("E: ");
 429                 hprintb(&node->elms[i].base);
 430                 printf("\n");
 431         }
 432 #endif
 433
 434         n = hammer_btree_search_node(&search, node);
 435
 436         for (; n < node->count; n++) {
 437                 e = &node->elms[n];
 438                 r = hammer_btree_cmp(&search, &e->base);
 439
 440                 if (r < 0)
 441                         break;
 442         }
 443
 444         // unless we stopped right on the left side, we need to back off a bit
 445         if (n > 0)
 446                 e = &node->elms[n - 1];
 447
 448 #if DEBUG > 2
 449         printf("  found: ");
 450         hprintb(&e->base);
 451         printf("\n");
 452 #endif
 453
 454         if (node->type == HAMMER_BTREE_TYPE_INTERNAL) {
 455                 nodeoff = e->internal.subtree_offset;
 456                 backtrack = (e+1)->base;
 457                 goto loop;
 458         }
 459
 460         r = hammer_btree_cmp(key, &e->base);
 461         // If we're more off than the createtid, take the next elem
 462         if (r > 1) {
 463                 e++;
 464                 n++;
 465         }
 466
 467         // Skip deleted elements
 468         while (n < node->count && e->base.delete_tid != 0) {
 469                 e++;
 470                 n++;
 471         }
 472
 473         // In the unfortunate event when there is no next
 474         // element in this node, we repeat the search with
 475         // a key beyond the right boundary
 476         if (n == node->count) {
 477                 search = backtrack;
 478                 nodeoff = hfs->root;
 479
 480 #if DEBUG > 2
 481                 printf("hit right boundary (%d), resetting search to ",
 482                        node->count);
 483                 hprintb(&search);
 484                 printf("\n");
 485 #endif
 486                 goto loop;
 487         }
 488
 489 #if DEBUG > 1
 490         printf("  result: ");
 491         hprintb(&e->base);
 492         printf("\n");
 493 #endif
 494
 495         if (end != NULL)
 496                 if (hammer_btree_cmp(end, &e->base) < -1)
 497                         goto fail;
 498
 499         return (&e->leaf);
 500
 501 fail:
 502 #if DEBUG > 1
 503         printf("  fail.\n");
 504 #endif
 505         return (NULL);
 506 }
 507
 508 #ifndef BOOT2
 509 static int
 510 hreaddir(struct hfs *hfs, ino_t ino, int64_t *off, struct dirent *de)
 511 {
 512         struct hammer_base_elm key, end;
 513
 514         bzero(&key, sizeof(key));
 515         key.obj_id = ino;
 516         key.localization = HAMMER_LOCALIZE_MISC;
 517         key.rec_type = HAMMER_RECTYPE_DIRENTRY;
 518         key.key = *off;
 519
 520         end = key;
 521         end.key = HAMMER_MAX_KEY;
 522
 523         hammer_btree_leaf_elm_t e;
 524
 525         e = hfind(hfs, &key, &end);
 526         if (e == NULL) {
 527                 errno = ENOENT;
 528                 return (-1);
 529         }
 530
 531         *off = e->base.key + 1;         // remember next pos
 532
 533         de->d_namlen = e->data_len - HAMMER_ENTRY_NAME_OFF;
 534         de->d_type = hammer_get_dtype(e->base.obj_type);
 535         hammer_data_ondisk_t ed = hread(hfs, e->data_offset);
 536         if (ed == NULL)
 537                 return (-1);
 538         de->d_ino = ed->entry.obj_id;
 539         bcopy(ed->entry.name, de->d_name, de->d_namlen);
 540         de->d_name[de->d_namlen] = 0;
 541
 542         return (0);
 543 }
 544 #endif
 545
 546 static ino_t
 547 hresolve(struct hfs *hfs, ino_t dirino, const char *name)
 548 {
 549         struct hammer_base_elm key, end;
 550         size_t namel = strlen(name);
 551
 552         bzero(&key, sizeof(key));
 553         key.obj_id = dirino;
 554         key.localization = HAMMER_LOCALIZE_MISC;
 555         key.key = hammer_directory_namekey(name, namel);
 556         key.rec_type = HAMMER_RECTYPE_DIRENTRY;
 557         end = key;
 558         end.key = HAMMER_MAX_KEY;
 559
 560         hammer_btree_leaf_elm_t e;
 561         while ((e = hfind(hfs, &key, &end)) != NULL) {
 562                 key.key = e->base.key + 1;
 563
 564                 size_t elen = e->data_len - HAMMER_ENTRY_NAME_OFF;
 565                 hammer_data_ondisk_t ed = hread(hfs, e->data_offset);
 566                 if (ed == NULL)
 567                         return (-1);
 568 #ifdef BOOT2
 569                 if (ls) {
 570                         for (int i = 0; i < elen; i++)
 571                                 putchar(ed->entry.name[i]);
 572                         putchar(' ');
 573                         ls = 2;
 574                         continue;
 575                 }
 576 #endif
 577                 if (elen == namel && memcmp(ed->entry.name, name, MIN(elen, namel)) == 0)
 578                         return (ed->entry.obj_id);
 579         }
 580
 581 #if BOOT2
 582         if (ls == 2)
 583                 printf("\n");
 584 #endif
 585
 586         return -1;
 587 }
 588
 589 static ino_t
 590 hlookup(struct hfs *hfs, const char *path)
 591 {
 592 #ifdef BOOT2
 593         ls = 0;
 594 #endif
 595         ino_t ino = 1;
 596         do {
 597                 char name[MAXPATHLEN + 1];
 598                 while (*path == '/')
 599                         path++;
 600                 for (char *n = name; *path != 0 && *path != '/'; path++, n++) {
 601                         n[0] = *path;
 602                         n[1] = 0;
 603                 }
 604
 605 #ifdef BOOT2
 606                 // A single ? means "list"
 607                 if (name[0] == '?' && name[1] == 0)
 608                         ls = 1;
 609 #endif
 610
 611                 ino = hresolve(hfs, ino, name);
 612         } while (ino != (ino_t)-1 && *path != 0);
 613
 614         return (ino);
 615 }
 616
 617
 618 #ifndef BOOT2
 619 static int
 620 hstat(struct hfs *hfs, ino_t ino, struct stat* st)
 621 {
 622         struct hammer_base_elm key;
 623
 624         bzero(&key, sizeof(key));
 625         key.obj_id = ino;
 626         key.localization = HAMMER_LOCALIZE_INODE;
 627         key.rec_type = HAMMER_RECTYPE_INODE;
 628
 629         hammer_btree_leaf_elm_t e = hfind(hfs, &key, &key);
 630         if (e == NULL) {
 631 #ifndef BOOT2
 632                 errno = ENOENT;
 633 #endif
 634                 return -1;
 635         }
 636
 637         hammer_data_ondisk_t ed = hread(hfs, e->data_offset);
 638         if (ed == NULL)
 639                 return (-1);
 640
 641         st->st_mode = ed->inode.mode | hammer_get_mode(ed->inode.obj_type);
 642         st->st_uid = hammer_to_unix_xid(&ed->inode.uid);
 643         st->st_gid = hammer_to_unix_xid(&ed->inode.gid);
 644         st->st_size = ed->inode.size;
 645
 646         return (0);
 647 }
 648 #endif
 649
 650 static ssize_t
 651 hreadf(struct hfs *hfs, ino_t ino, int64_t off, int64_t len, char *buf)
 652 {
 653         int64_t startoff = off;
 654         struct hammer_base_elm key, end;
 655
 656         bzero(&key, sizeof(key));
 657         key.obj_id = ino;
 658         key.localization = HAMMER_LOCALIZE_MISC;
 659         key.rec_type = HAMMER_RECTYPE_DATA;
 660         end = key;
 661         end.key = HAMMER_MAX_KEY;
 662
 663         while (len > 0) {
 664                 key.key = off + 1;
 665                 hammer_btree_leaf_elm_t e = hfind(hfs, &key, &end);
 666                 int64_t dlen;
 667
 668                 if (e == NULL || off > e->base.key) {
 669                         bzero(buf, len);
 670                         off += len;
 671                         len = 0;
 672                         break;
 673                 }
 674
 675                 int64_t doff = e->base.key - e->data_len;
 676                 if (off < doff) {
 677                         // sparse file, beginning
 678                         dlen = doff - off;
 679                         dlen = MIN(dlen, len);
 680                         bzero(buf, dlen);
 681                 } else {
 682                         int64_t boff = off - doff;
 683                         hammer_off_t roff = e->data_offset;
 684
 685                         dlen = e->data_len;
 686                         dlen -= boff;
 687                         dlen = MIN(dlen, len);
 688
 689                         while (boff >= HAMMER_BUFSIZE) {
 690                                 boff -= HAMMER_BUFSIZE;
 691                                 roff += HAMMER_BUFSIZE;
 692                         }
 693
 694                         // cut to HAMMER_BUFSIZE
 695                         if ((roff & ~HAMMER_BUFMASK) != ((roff + dlen - 1) & ~HAMMER_BUFMASK))
 696                                 dlen = HAMMER_BUFSIZE - ((boff + roff) & HAMMER_BUFMASK);
 697
 698                         char *data = hread(hfs, roff);
 699                         if (data == NULL)
 700                                 return (-1);
 701                         bcopy(data + boff, buf, dlen);
 702                 }
 703
 704                 buf += dlen;
 705                 off += dlen;
 706                 len -= dlen;
 707         }
 708
 709         return (off - startoff);
 710 }
 711
 712 #ifdef BOOT2
 713 struct hfs hfs;
 714
 715 static int
 716 hammerinit(void)
 717 {
 718         if (dsk_meta)
 719                 return (0);
 720
 721         hammer_volume_ondisk_t volhead = hread(&hfs, HAMMER_ZONE_ENCODE(1, 0));
 722         if (volhead == NULL)
 723                 return (-1);
 724         if (volhead->vol_signature != HAMMER_FSBUF_VOLUME)
 725                 return (-1);
 726         hfs.root = volhead->vol0_btree_root;
 727         hfs.buf_beg = volhead->vol_buf_beg;
 728         dsk_meta++;
 729         return (0);
 730 }
 731
 732 static ino_t
 733 lookup(const char *path)
 734 {
 735         hammerinit();
 736
 737         ino_t ino = hlookup(&hfs, path);
 738
 739         if (ino == -1)
 740                 ino = 0;
 741         return (ino);
 742 }
 743
 744 static ssize_t
 745 fsread(ino_t ino, void *buf, size_t len)
 746 {
 747         hammerinit();
 748
 749         ssize_t rlen = hreadf(&hfs, ino, fs_off, len, buf);
 750         if (rlen != -1)
 751                 fs_off += rlen;
 752         return (rlen);
 753 }
 754 #endif
 755
 756 #ifndef BOOT2
 757 static int
 758 hinit(struct hfs *hfs)
 759 {
 760 #if DEBUG
 761         printf("hinit\n");
 762 #endif
 763         for (int i = 0; i < NUMCACHE; i++) {
 764                 hfs->cache[i].data = malloc(HAMMER_BUFSIZE);
 765                 hfs->cache[i].off = -1; // invalid
 766                 hfs->cache[i].use = 0;
 767
 768 #if DEBUG
 769                 if (hfs->cache[i].data == NULL)
 770                         printf("malloc failed\n");
 771 #endif
 772         }
 773         hfs->lru = 0;
 774
 775         hammer_volume_ondisk_t volhead = hread(hfs, HAMMER_ZONE_ENCODE(1, 0));
 776         if (volhead == NULL)
 777                 return (-1);
 778
 779 #ifdef TESTING
 780         printf("signature: %svalid\n",
 781                volhead->vol_signature != HAMMER_FSBUF_VOLUME ?
 782                         "in" :
 783                         "");
 784         printf("name: %s\n", volhead->vol_name);
 785 #endif
 786
 787         if (volhead->vol_signature != HAMMER_FSBUF_VOLUME) {
 788                 for (int i = 0; i < NUMCACHE; i++)
 789                         free(hfs->cache[i].data);
 790                 errno = ENODEV;
 791                 return (-1);
 792         }
 793
 794         hfs->root = volhead->vol0_btree_root;
 795         hfs->buf_beg = volhead->vol_buf_beg;
 796
 797         return (0);
 798 }
 799
 800 static void
 801 hclose(struct hfs *hfs)
 802 {
 803 #if DEBUG
 804         printf("hclose\n");
 805 #endif
 806         for (int i = 0; i < NUMCACHE; i++)
 807                 free(hfs->cache[i].data);
 808 }
 809 #endif
 810
 811 #ifdef LIBSTAND
 812 struct hfile {
 813         struct hfs      hfs;
 814         ino_t           ino;
 815         int64_t         fsize;
 816 };
 817
 818 static int
 819 hammer_open(const char *path, struct open_file *f)
 820 {
 821         struct hfile *hf = malloc(sizeof(*hf));
 822         bzero(hf, sizeof(*hf));
 823
 824         f->f_fsdata = hf;
 825         hf->hfs.f = f;
 826         f->f_offset = 0;
 827
 828         int rv = hinit(&hf->hfs);
 829         if (rv) {
 830                 free(hf);
 831                 return (rv);
 832         }
 833
 834 #if DEBUG
 835         printf("hammer_open %s %p %ld\n", path, f);
 836 #endif
 837
 838         hf->ino = hlookup(&hf->hfs, path);
 839         if (hf->ino == -1)
 840                 goto fail;
 841
 842         struct stat st;
 843         if (hstat(&hf->hfs, hf->ino, &st) == -1)
 844                 goto fail;
 845         hf->fsize = st.st_size;
 846
 847 #if DEBUG
 848         printf("        %ld\n", (long)hf->fsize);
 849 #endif
 850
 851         return (0);
 852
 853 fail:
 854 #if DEBUG
 855         printf("hammer_open fail\n");
 856 #endif
 857         hclose(&hf->hfs);
 858         free(hf);
 859         return (ENOENT);
 860 }
 861
 862 static int
 863 hammer_close(struct open_file *f)
 864 {
 865         struct hfile *hf = f->f_fsdata;
 866
 867         hclose(&hf->hfs);
 868         f->f_fsdata = NULL;
 869         free(hf);
 870         return (0);
 871 }
 872
 873 static int
 874 hammer_read(struct open_file *f, void *buf, size_t len, size_t *resid)
 875 {
 876         struct hfile *hf = f->f_fsdata;
 877
 878 #if DEBUG
 879         printf("hammer_read %p %ld %ld\n", f, f->f_offset, len);
 880 #endif
 881
 882         if (f->f_offset >= hf->fsize)
 883                 return (EINVAL);
 884
 885         size_t maxlen = len;
 886         if (f->f_offset + len > hf->fsize)
 887                 maxlen = hf->fsize - f->f_offset;
 888
 889         ssize_t rlen = hreadf(&hf->hfs, hf->ino, f->f_offset, maxlen, buf);
 890         if (rlen == -1)
 891                 return (EINVAL);
 892
 893         f->f_offset += rlen;
 894
 895         *resid = len - rlen;
 896         return (0);
 897 }
 898
 899 static off_t
 900 hammer_seek(struct open_file *f, off_t offset, int whence)
 901 {
 902         struct hfile *hf = f->f_fsdata;
 903
 904         switch (whence) {
 905         case SEEK_SET:
 906                 f->f_offset = offset;
 907                 break;
 908         case SEEK_CUR:
 909                 f->f_offset += offset;
 910                 break;
 911         case SEEK_END:
 912                 f->f_offset = hf->fsize - offset;
 913                 break;
 914         default:
 915                 return (-1);
 916         }
 917         return (f->f_offset);
 918 }
 919
 920 static int
 921 hammer_stat(struct open_file *f, struct stat *st)
 922 {
 923         struct hfile *hf = f->f_fsdata;
 924
 925         return (hstat(&hf->hfs, hf->ino, st));
 926 }
 927
 928 static int
 929 hammer_readdir(struct open_file *f, struct dirent *d)
 930 {
 931         struct hfile *hf = f->f_fsdata;
 932
 933         int64_t off = f->f_offset;
 934         int rv = hreaddir(&hf->hfs, hf->ino, &off, d);
 935         f->f_offset = off;
 936         return (rv);
 937 }
 938
 939 // libstand
 940 struct fs_ops hammer_fsops = {
 941         "hammer",
 942         hammer_open,
 943         hammer_close,
 944         hammer_read,
 945         null_write,
 946         hammer_seek,
 947         hammer_stat,
 948         hammer_readdir
 949 };
 950 #endif  // LIBSTAND
 951
 952 #ifdef TESTING
 953 int
 954 main(int argc, char **argv)
 955 {
 956         if (argc < 2) {
 957                 fprintf(stderr, "usage: hammerread <dev>\n");
 958                 return (1);
 959         }
 960
 961         struct hfs hfs;
 962         hfs.fd = open(argv[1], O_RDONLY);
 963         if (hfs.fd == -1)
 964                 err(1, "unable to open %s", argv[1]);
 965
 966         if (hinit(&hfs) == -1)
 967                 err(1, "invalid hammerfs");
 968
 969         for (int i = 2; i < argc; i++) {
 970                 ino_t ino = hlookup(&hfs, argv[i]);
 971                 if (ino == (ino_t)-1) {
 972                         warn("hlookup %s", argv[i]);
 973                         continue;
 974                 }
 975
 976                 struct stat st;
 977                 if (hstat(&hfs, ino, &st)) {
 978                         warn("hstat %s", argv[i]);
 979                         continue;
 980                 }
 981
 982                 printf("%s %d/%d %o %lld\n",
 983                        argv[i],
 984                        st.st_uid, st.st_gid,
 985                        st.st_mode, st.st_size);
 986
 987                 if (S_ISDIR(st.st_mode)) {
 988                         int64_t off = 0;
 989                         struct dirent de;
 990                         while (hreaddir(&hfs, ino, &off, &de) == 0) {
 991                                 printf("%s %d %llx\n",
 992                                        de.d_name, de.d_type, de.d_ino);
 993                         }
 994                 } else if (S_ISREG(st.st_mode)) {
 995                         char *buf = malloc(100000);
 996                         int64_t off = 0;
 997                         while (off < st.st_size) {
 998                                 int64_t len = MIN(100000, st.st_size - off);
 999                                 int64_t rl = hreadf(&hfs, ino, off, len, buf);
1000                                 fwrite(buf, rl, 1, stdout);
1001                                 off += rl;
1002                         }
1003                         free(buf);
1004                 }
1005         }
1006
1007         return 0;
1008 }
1009 #endif