debugfs/logdump.c

   1 /*
   2  * logdump.c --- dump the contents of the journal out to a file
   3  *
   4  * Authro: Stephen C. Tweedie, 2001  <sct@redhat.com>
   5  * Copyright (C) 2001 Red Hat, Inc.
   6  * Based on portions  Copyright (C) 1994 Theodore Ts'o.
   7  *
   8  * This file may be redistributed under the terms of the GNU Public
   9  * License.
  10  */
  11
  12 #include <stdio.h>
  13 #include <unistd.h>
  14 #include <stdlib.h>
  15 #include <ctype.h>
  16 #include <string.h>
  17 #include <time.h>
  18 #ifdef HAVE_ERRNO_H
  19 #include <errno.h>
  20 #endif
  21 #include <sys/types.h>
  22 #include <sys/stat.h>
  23 #include <fcntl.h>
  24 #include <utime.h>
  25 #ifdef HAVE_GETOPT_H
  26 #include <getopt.h>
  27 #else
  28 extern int optind;
  29 extern char *optarg;
  30 #endif
  31
  32 #include "debugfs.h"
  33 #include "blkid/blkid.h"
  34 #include "jfs_user.h"
  35 #include <uuid/uuid.h>
  36
  37 enum journal_location {JOURNAL_IS_INTERNAL, JOURNAL_IS_EXTERNAL};
  38
  39 #define ANY_BLOCK ((blk_t) -1)
  40
  41 int             dump_all, dump_contents, dump_descriptors;
  42 blk_t           block_to_dump, bitmap_to_dump, inode_block_to_dump;
  43 unsigned int    group_to_dump, inode_offset_to_dump;
  44 ext2_ino_t      inode_to_dump;
  45
  46 struct journal_source
  47 {
  48         enum journal_location where;
  49         int fd;
  50         ext2_file_t file;
  51 };
  52
  53 static void dump_journal(char *, FILE *, struct journal_source *);
  54
  55 static void dump_descriptor_block(FILE *, struct journal_source *,
  56                                   char *, journal_superblock_t *,
  57                                   unsigned int *, int, tid_t);
  58
  59 static void dump_revoke_block(FILE *, char *, journal_superblock_t *,
  60                                   unsigned int, int, tid_t);
  61
  62 static void dump_metadata_block(FILE *, struct journal_source *,
  63                                 journal_superblock_t*,
  64                                 unsigned int, unsigned int, unsigned int,
  65                                 int, tid_t);
  66
  67 static void do_hexdump (FILE *, char *, int);
  68
  69 #define WRAP(jsb, blocknr)                                      \
  70         if (blocknr >= be32_to_cpu((jsb)->s_maxlen))            \
  71                 blocknr -= (be32_to_cpu((jsb)->s_maxlen) -      \
  72                             be32_to_cpu((jsb)->s_first));
  73
  74 void do_logdump(int argc, char **argv)
  75 {
  76         int             c;
  77         int             retval;
  78         char            *out_fn;
  79         FILE            *out_file;
  80
  81         char            *inode_spec = NULL;
  82         char            *journal_fn = NULL;
  83         int             journal_fd = 0;
  84         int             use_sb = 0;
  85         ext2_ino_t      journal_inum;
  86         struct ext2_inode journal_inode;
  87         ext2_file_t     journal_file;
  88         char            *tmp;
  89         struct journal_source journal_source;
  90         struct ext2_super_block *es = NULL;
  91
  92         journal_source.where = JOURNAL_IS_INTERNAL;
  93         journal_source.fd = 0;
  94         journal_source.file = 0;
  95         dump_all = 0;
  96         dump_contents = 0;
  97         dump_descriptors = 1;
  98         block_to_dump = ANY_BLOCK;
  99         bitmap_to_dump = -1;
 100         inode_block_to_dump = ANY_BLOCK;
 101         inode_to_dump = -1;
 102
 103         reset_getopt();
 104         while ((c = getopt (argc, argv, "ab:ci:f:s")) != EOF) {
 105                 switch (c) {
 106                 case 'a':
 107                         dump_all++;
 108                         break;
 109                 case 'b':
 110                         block_to_dump = strtoul(optarg, &tmp, 0);
 111                         if (*tmp) {
 112                                 com_err(argv[0], 0,
 113                                         "Bad block number - %s", optarg);
 114                                 return;
 115                         }
 116                         dump_descriptors = 0;
 117                         break;
 118                 case 'c':
 119                         dump_contents++;
 120                         break;
 121                 case 'f':
 122                         journal_fn = optarg;
 123                         break;
 124                 case 'i':
 125                         inode_spec = optarg;
 126                         dump_descriptors = 0;
 127                         break;
 128                 case 's':
 129                         use_sb++;
 130                         break;
 131                 default:
 132                         goto print_usage;
 133                 }
 134         }
 135         if (optind != argc && optind != argc-1) {
 136                 goto print_usage;
 137         }
 138
 139         if (current_fs)
 140                 es = current_fs->super;
 141
 142         if (inode_spec) {
 143                 int inode_group, group_offset, inodes_per_block;
 144
 145                 if (check_fs_open(argv[0]))
 146                         return;
 147
 148                 inode_to_dump = string_to_inode(inode_spec);
 149                 if (!inode_to_dump)
 150                         return;
 151
 152                 inode_group = ((inode_to_dump - 1)
 153                                / es->s_inodes_per_group);
 154                 group_offset = ((inode_to_dump - 1)
 155                                 % es->s_inodes_per_group);
 156                 inodes_per_block = (current_fs->blocksize
 157                                     / sizeof(struct ext2_inode));
 158
 159                 inode_block_to_dump =
 160                         current_fs->group_desc[inode_group].bg_inode_table +
 161                         (group_offset / inodes_per_block);
 162                 inode_offset_to_dump = ((group_offset % inodes_per_block)
 163                                         * sizeof(struct ext2_inode));
 164                 printf("Inode %u is at group %u, block %u, offset %u\n",
 165                        inode_to_dump, inode_group,
 166                        inode_block_to_dump, inode_offset_to_dump);
 167         }
 168
 169         if (optind == argc) {
 170                 out_file = stdout;
 171         } else {
 172                 out_fn = argv[optind];
 173                 out_file = fopen(out_fn, "w");
 174                 if (!out_file) {
 175                         com_err(argv[0], errno, "while opening %s for logdump",
 176                                 out_fn);
 177                         goto errout;
 178                 }
 179         }
 180
 181         if (block_to_dump != ANY_BLOCK && current_fs != NULL) {
 182                 group_to_dump = ((block_to_dump -
 183                                   es->s_first_data_block)
 184                                  / es->s_blocks_per_group);
 185                 bitmap_to_dump = current_fs->group_desc[group_to_dump].bg_block_bitmap;
 186         }
 187
 188         if (!journal_fn && check_fs_open(argv[0]))
 189                 goto errout;
 190
 191         if (journal_fn) {
 192                 /* Set up to read journal from a regular file somewhere */
 193                 journal_fd = open(journal_fn, O_RDONLY, 0);
 194                 if (journal_fd < 0) {
 195                         com_err(argv[0], errno, "while opening %s for logdump",
 196                                 journal_fn);
 197                         goto errout;
 198                 }
 199
 200                 journal_source.where = JOURNAL_IS_EXTERNAL;
 201                 journal_source.fd = journal_fd;
 202         } else if ((journal_inum = es->s_journal_inum)) {
 203                 if (use_sb) {
 204                         if (es->s_jnl_backup_type != EXT3_JNL_BACKUP_BLOCKS) {
 205                                 com_err(argv[0], 0,
 206                                         "no journal backup in super block\n");
 207                                 goto errout;
 208                         }
 209                         memset(&journal_inode, 0, sizeof(struct ext2_inode));
 210                         memcpy(&journal_inode.i_block[0], es->s_jnl_blocks,
 211                                EXT2_N_BLOCKS*4);
 212                         journal_inode.i_size = es->s_jnl_blocks[16];
 213                         journal_inode.i_links_count = 1;
 214                         journal_inode.i_mode = LINUX_S_IFREG | 0600;
 215                 } else {
 216                         if (debugfs_read_inode(journal_inum, &journal_inode,
 217                                                argv[0]))
 218                                 goto errout;
 219                 }
 220
 221                 retval = ext2fs_file_open2(current_fs, journal_inum,
 222                                            &journal_inode, 0, &journal_file);
 223                 if (retval) {
 224                         com_err(argv[0], retval, "while opening ext2 file");
 225                         goto errout;
 226                 }
 227                 journal_source.where = JOURNAL_IS_INTERNAL;
 228                 journal_source.file = journal_file;
 229         } else {
 230                 char uuid[37];
 231
 232                 uuid_unparse(es->s_journal_uuid, uuid);
 233                 journal_fn = blkid_get_devname(NULL, "UUID", uuid);
 234                 if (!journal_fn)
 235                                 journal_fn = blkid_devno_to_devname(es->s_journal_dev);
 236                 if (!journal_fn) {
 237                         com_err(argv[0], 0, "filesystem has no journal");
 238                         goto errout;
 239                 }
 240                 journal_fd = open(journal_fn, O_RDONLY, 0);
 241                 if (journal_fd < 0) {
 242                         com_err(argv[0], errno, "while opening %s for logdump",
 243                                 journal_fn);
 244                         free(journal_fn);
 245                         goto errout;
 246                 }
 247                 fprintf(out_file, "Using external journal found at %s\n",
 248                         journal_fn);
 249                 free(journal_fn);
 250                 journal_source.where = JOURNAL_IS_EXTERNAL;
 251                 journal_source.fd = journal_fd;
 252         }
 253
 254         dump_journal(argv[0], out_file, &journal_source);
 255
 256         if (journal_source.where == JOURNAL_IS_INTERNAL)
 257                 ext2fs_file_close(journal_file);
 258         else
 259                 close(journal_fd);
 260
 261 errout:
 262         if (out_file && (out_file != stdout))
 263                 fclose(out_file);
 264
 265         return;
 266
 267 print_usage:
 268         fprintf(stderr, "%s: Usage: logdump [-acs] [-b<block>] [-i<filespec>]\n\t"
 269                 "[-f<journal_file>] [output_file]\n", argv[0]);
 270 }
 271
 272
 273 static int read_journal_block(const char *cmd, struct journal_source *source,
 274                               off_t offset, char *buf, int size,
 275                               unsigned int *got)
 276 {
 277         int retval;
 278
 279         if (source->where == JOURNAL_IS_EXTERNAL) {
 280                 if (lseek(source->fd, offset, SEEK_SET) < 0) {
 281                         retval = errno;
 282                         com_err(cmd, retval, "while seeking in reading journal");
 283                         return retval;
 284                 }
 285                 retval = read(source->fd, buf, size);
 286                 if (retval >= 0) {
 287                         *got = retval;
 288                         retval = 0;
 289                 } else
 290                         retval = errno;
 291         } else {
 292                 retval = ext2fs_file_lseek(source->file, offset,
 293                                            EXT2_SEEK_SET, NULL);
 294                 if (retval) {
 295                         com_err(cmd, retval, "while seeking in reading journal");
 296                         return retval;
 297                 }
 298
 299                 retval = ext2fs_file_read(source->file, buf, size, got);
 300         }
 301
 302         if (retval)
 303                 com_err(cmd, retval, "while reading journal");
 304         else if (*got != (unsigned int) size) {
 305                 com_err(cmd, 0, "short read (read %d, expected %d) "
 306                         "while reading journal", *got, size);
 307                 retval = -1;
 308         }
 309
 310         return retval;
 311 }
 312
 313 static const char *type_to_name(int btype)
 314 {
 315         switch (btype) {
 316         case JFS_DESCRIPTOR_BLOCK:
 317                 return "descriptor block";
 318         case JFS_COMMIT_BLOCK:
 319                 return "commit block";
 320         case JFS_SUPERBLOCK_V1:
 321                 return "V1 superblock";
 322         case JFS_SUPERBLOCK_V2:
 323                 return "V2 superblock";
 324         case JFS_REVOKE_BLOCK:
 325                 return "revoke table";
 326         }
 327         return "unrecognised type";
 328 }
 329
 330
 331 static void dump_journal(char *cmdname, FILE *out_file,
 332                          struct journal_source *source)
 333 {
 334         struct ext2_super_block *sb;
 335         char                    jsb_buffer[1024];
 336         char                    buf[8192];
 337         journal_superblock_t    *jsb;
 338         unsigned int            blocksize = 1024;
 339         unsigned int            got;
 340         int                     retval;
 341         __u32                   magic, sequence, blocktype;
 342         journal_header_t        *header;
 343
 344         tid_t                   transaction;
 345         unsigned int            blocknr = 0;
 346
 347         /* First, check to see if there's an ext2 superblock header */
 348         retval = read_journal_block(cmdname, source, 0,
 349                                     buf, 2048, &got);
 350         if (retval)
 351                 return;
 352
 353         jsb = (journal_superblock_t *) buf;
 354         sb = (struct ext2_super_block *) (buf+1024);
 355 #ifdef WORDS_BIGENDIAN
 356         if (sb->s_magic == ext2fs_swab16(EXT2_SUPER_MAGIC))
 357                 ext2fs_swap_super(sb);
 358 #endif
 359
 360         if ((be32_to_cpu(jsb->s_header.h_magic) != JFS_MAGIC_NUMBER) &&
 361             (sb->s_magic == EXT2_SUPER_MAGIC) &&
 362             (sb->s_feature_incompat & EXT3_FEATURE_INCOMPAT_JOURNAL_DEV)) {
 363                 blocksize = EXT2_BLOCK_SIZE(sb);
 364                 blocknr = (blocksize == 1024) ? 2 : 1;
 365                 uuid_unparse(sb->s_uuid, jsb_buffer);
 366                 fprintf(out_file, "Ext2 superblock header found.\n");
 367                 if (dump_all) {
 368                         fprintf(out_file, "\tuuid=%s\n", jsb_buffer);
 369                         fprintf(out_file, "\tblocksize=%d\n", blocksize);
 370                         fprintf(out_file, "\tjournal data size %lu\n",
 371                                 (unsigned long) ext2fs_blocks_count(sb));
 372                 }
 373         }
 374
 375         /* Next, read the journal superblock */
 376
 377         retval = read_journal_block(cmdname, source, blocknr*blocksize,
 378                                     jsb_buffer, 1024, &got);
 379         if (retval)
 380                 return;
 381
 382         jsb = (journal_superblock_t *) jsb_buffer;
 383         if (be32_to_cpu(jsb->s_header.h_magic) != JFS_MAGIC_NUMBER) {
 384                 fprintf(out_file,
 385                         "Journal superblock magic number invalid!\n");
 386                 return;
 387         }
 388         blocksize = be32_to_cpu(jsb->s_blocksize);
 389         transaction = be32_to_cpu(jsb->s_sequence);
 390         blocknr = be32_to_cpu(jsb->s_start);
 391
 392         fprintf(out_file, "Journal starts at block %u, transaction %u\n",
 393                 blocknr, transaction);
 394
 395         if (!blocknr)
 396                 /* Empty journal, nothing to do. */
 397                 return;
 398
 399         while (1) {
 400                 retval = read_journal_block(cmdname, source,
 401                                             blocknr*blocksize, buf,
 402                                             blocksize, &got);
 403                 if (retval || got != blocksize)
 404                         return;
 405
 406                 header = (journal_header_t *) buf;
 407
 408                 magic = be32_to_cpu(header->h_magic);
 409                 sequence = be32_to_cpu(header->h_sequence);
 410                 blocktype = be32_to_cpu(header->h_blocktype);
 411
 412                 if (magic != JFS_MAGIC_NUMBER) {
 413                         fprintf (out_file, "No magic number at block %u: "
 414                                  "end of journal.\n", blocknr);
 415                         return;
 416                 }
 417
 418                 if (sequence != transaction) {
 419                         fprintf (out_file, "Found sequence %u (not %u) at "
 420                                  "block %u: end of journal.\n",
 421                                  sequence, transaction, blocknr);
 422                         return;
 423                 }
 424
 425                 if (dump_descriptors) {
 426                         fprintf (out_file, "Found expected sequence %u, "
 427                                  "type %u (%s) at block %u\n",
 428                                  sequence, blocktype,
 429                                  type_to_name(blocktype), blocknr);
 430                 }
 431
 432                 switch (blocktype) {
 433                 case JFS_DESCRIPTOR_BLOCK:
 434                         dump_descriptor_block(out_file, source, buf, jsb,
 435                                               &blocknr, blocksize,
 436                                               transaction);
 437                         continue;
 438
 439                 case JFS_COMMIT_BLOCK:
 440                         transaction++;
 441                         blocknr++;
 442                         WRAP(jsb, blocknr);
 443                         continue;
 444
 445                 case JFS_REVOKE_BLOCK:
 446                         dump_revoke_block(out_file, buf, jsb,
 447                                           blocknr, blocksize,
 448                                           transaction);
 449                         blocknr++;
 450                         WRAP(jsb, blocknr);
 451                         continue;
 452
 453                 default:
 454                         fprintf (out_file, "Unexpected block type %u at "
 455                                  "block %u.\n", blocktype, blocknr);
 456                         return;
 457                 }
 458         }
 459 }
 460
 461
 462 static void dump_descriptor_block(FILE *out_file,
 463                                   struct journal_source *source,
 464                                   char *buf,
 465                                   journal_superblock_t *jsb,
 466                                   unsigned int *blockp, int blocksize,
 467                                   tid_t transaction)
 468 {
 469         int                     offset, tag_size = JBD_TAG_SIZE32;
 470         char                    *tagp;
 471         journal_block_tag_t     *tag;
 472         unsigned int            blocknr;
 473         __u32                   tag_block;
 474         __u32                   tag_flags;
 475
 476         if (be32_to_cpu(jsb->s_feature_incompat) & JFS_FEATURE_INCOMPAT_64BIT)
 477                 tag_size = JBD_TAG_SIZE64;
 478
 479         offset = sizeof(journal_header_t);
 480         blocknr = *blockp;
 481
 482         if (dump_all)
 483                 fprintf(out_file, "Dumping descriptor block, sequence %u, at "
 484                         "block %u:\n", transaction, blocknr);
 485
 486         ++blocknr;
 487         WRAP(jsb, blocknr);
 488
 489         do {
 490                 /* Work out the location of the current tag, and skip to
 491                  * the next one... */
 492                 tagp = &buf[offset];
 493                 tag = (journal_block_tag_t *) tagp;
 494                 offset += tag_size;
 495
 496                 /* ... and if we have gone too far, then we've reached the
 497                    end of this block. */
 498                 if (offset > blocksize)
 499                         break;
 500
 501                 tag_block = be32_to_cpu(tag->t_blocknr);
 502                 tag_flags = be32_to_cpu(tag->t_flags);
 503
 504                 if (!(tag_flags & JFS_FLAG_SAME_UUID))
 505                         offset += 16;
 506
 507                 dump_metadata_block(out_file, source, jsb,
 508                                     blocknr, tag_block, tag_flags, blocksize,
 509                                     transaction);
 510
 511                 ++blocknr;
 512                 WRAP(jsb, blocknr);
 513
 514         } while (!(tag_flags & JFS_FLAG_LAST_TAG));
 515
 516         *blockp = blocknr;
 517 }
 518
 519
 520 static void dump_revoke_block(FILE *out_file, char *buf,
 521                               journal_superblock_t *jsb EXT2FS_ATTR((unused)),
 522                               unsigned int blocknr,
 523                               int blocksize EXT2FS_ATTR((unused)),
 524                               tid_t transaction)
 525 {
 526         int                     offset, max;
 527         journal_revoke_header_t *header;
 528         unsigned int            *entry, rblock;
 529
 530         if (dump_all)
 531                 fprintf(out_file, "Dumping revoke block, sequence %u, at "
 532                         "block %u:\n", transaction, blocknr);
 533
 534         header = (journal_revoke_header_t *) buf;
 535         offset = sizeof(journal_revoke_header_t);
 536         max = be32_to_cpu(header->r_count);
 537
 538         while (offset < max) {
 539                 entry = (unsigned int *) (buf + offset);
 540                 rblock = be32_to_cpu(*entry);
 541                 if (dump_all || rblock == block_to_dump) {
 542                         fprintf(out_file, "  Revoke FS block %u", rblock);
 543                         if (dump_all)
 544                                 fprintf(out_file, "\n");
 545                         else
 546                                 fprintf(out_file," at block %u, sequence %u\n",
 547                                         blocknr, transaction);
 548                 }
 549                 offset += 4;
 550         }
 551 }
 552
 553
 554 static void show_extent(FILE *out_file, int start_extent, int end_extent,
 555                         __u32 first_block)
 556 {
 557         if (start_extent >= 0 && first_block != 0)
 558                 fprintf(out_file, "(%d+%u): %u ",
 559                         start_extent, end_extent-start_extent, first_block);
 560 }
 561
 562 static void show_indirect(FILE *out_file, const char *name, __u32 where)
 563 {
 564         if (where)
 565                 fprintf(out_file, "(%s): %u ", name, where);
 566 }
 567
 568
 569 static void dump_metadata_block(FILE *out_file, struct journal_source *source,
 570                                 journal_superblock_t *jsb EXT2FS_ATTR((unused)),
 571                                 unsigned int log_blocknr,
 572                                 unsigned int fs_blocknr,
 573                                 unsigned int log_tag_flags,
 574                                 int blocksize,
 575                                 tid_t transaction)
 576 {
 577         unsigned int    got;
 578         int             retval;
 579         char            buf[8192];
 580
 581         if (!(dump_all
 582               || (fs_blocknr == block_to_dump)
 583               || (fs_blocknr == inode_block_to_dump)
 584               || (fs_blocknr == bitmap_to_dump)))
 585                 return;
 586
 587         fprintf(out_file, "  FS block %u logged at ", fs_blocknr);
 588         if (!dump_all)
 589                 fprintf(out_file, "sequence %u, ", transaction);
 590         fprintf(out_file, "journal block %u (flags 0x%x)\n", log_blocknr,
 591                 log_tag_flags);
 592
 593         /* There are two major special cases to parse:
 594          *
 595          * If this block is a block
 596          * bitmap block, we need to give it special treatment so that we
 597          * can log any allocates and deallocates which affect the
 598          * block_to_dump query block.
 599          *
 600          * If the block is an inode block for the inode being searched
 601          * for, then we need to dump the contents of that inode
 602          * structure symbolically.
 603          */
 604
 605         if (!(dump_contents && dump_all)
 606             && fs_blocknr != block_to_dump
 607             && fs_blocknr != bitmap_to_dump
 608             && fs_blocknr != inode_block_to_dump)
 609                 return;
 610
 611         retval = read_journal_block("logdump", source,
 612                                     blocksize * log_blocknr,
 613                                     buf, blocksize, &got);
 614         if (retval)
 615                 return;
 616
 617         if (fs_blocknr == bitmap_to_dump) {
 618                 struct ext2_super_block *super;
 619                 int offset;
 620
 621                 super = current_fs->super;
 622                 offset = ((fs_blocknr - super->s_first_data_block) %
 623                           super->s_blocks_per_group);
 624
 625                 fprintf(out_file, "    (block bitmap for block %u: "
 626                         "block is %s)\n",
 627                         block_to_dump,
 628                         ext2fs_test_bit(offset, buf) ? "SET" : "CLEAR");
 629         }
 630
 631         if (fs_blocknr == inode_block_to_dump) {
 632                 struct ext2_inode *inode;
 633                 int first, prev, this, start_extent, i;
 634
 635                 fprintf(out_file, "    (inode block for inode %u):\n",
 636                         inode_to_dump);
 637
 638                 inode = (struct ext2_inode *) (buf + inode_offset_to_dump);
 639                 internal_dump_inode(out_file, "    ", inode_to_dump, inode, 0);
 640
 641                 /* Dump out the direct/indirect blocks here:
 642                  * internal_dump_inode can only dump them from the main
 643                  * on-disk inode, not from the journaled copy of the
 644                  * inode. */
 645
 646                 fprintf (out_file, "    Blocks:  ");
 647                 first = prev = start_extent = -1;
 648
 649                 for (i=0; i<EXT2_NDIR_BLOCKS; i++) {
 650                         this = inode->i_block[i];
 651                         if (start_extent >= 0  && this == prev+1) {
 652                                 prev = this;
 653                                 continue;
 654                         } else {
 655                                 show_extent(out_file, start_extent, i, first);
 656                                 start_extent = i;
 657                                 first = prev = this;
 658                         }
 659                 }
 660                 show_extent(out_file, start_extent, i, first);
 661                 show_indirect(out_file, "IND", inode->i_block[i++]);
 662                 show_indirect(out_file, "DIND", inode->i_block[i++]);
 663                 show_indirect(out_file, "TIND", inode->i_block[i++]);
 664
 665                 fprintf(out_file, "\n");
 666         }
 667
 668         if (dump_contents)
 669                 do_hexdump(out_file, buf, blocksize);
 670
 671 }
 672
 673 static void do_hexdump (FILE *out_file, char *buf, int blocksize)
 674 {
 675         int i,j;
 676         int *intp;
 677         char *charp;
 678         unsigned char c;
 679
 680         intp = (int *) buf;
 681         charp = (char *) buf;
 682
 683         for (i=0; i<blocksize; i+=16) {
 684                 fprintf(out_file, "    %04x:  ", i);
 685                 for (j=0; j<16; j+=4)
 686                         fprintf(out_file, "%08x ", *intp++);
 687                 for (j=0; j<16; j++) {
 688                         c = *charp++;
 689                         if (c < ' ' || c >= 127)
 690                                 c = '.';
 691                         fprintf(out_file, "%c", c);
 692                 }
 693                 fprintf(out_file, "\n");
 694         }
 695 }
 696