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debugfs.8, e2fsck.8: clarify man pages these programs can operate on files
[tools/e2fsprogs.git] / 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 "config.h"
13 #include <stdio.h>
14 #include <unistd.h>
15 #include <stdlib.h>
16 #include <ctype.h>
17 #include <string.h>
18 #include <time.h>
19 #ifdef HAVE_ERRNO_H
20 #include <errno.h>
21 #endif
22 #include <sys/types.h>
23 #include <sys/stat.h>
24 #include <fcntl.h>
25 #include <utime.h>
26 #ifdef HAVE_GETOPT_H
27 #include <getopt.h>
28 #else
29 extern int optind;
30 extern char *optarg;
31 #endif
32
33 #include "debugfs.h"
34 #include "blkid/blkid.h"
35 #include "jfs_user.h"
36 #include <uuid/uuid.h>
37
38 enum journal_location {JOURNAL_IS_INTERNAL, JOURNAL_IS_EXTERNAL};
39
40 #define ANY_BLOCK ((blk64_t) -1)
41
42 static int              dump_all, dump_old, dump_contents, dump_descriptors;
43 static blk64_t          block_to_dump, bitmap_to_dump, inode_block_to_dump;
44 static unsigned int     group_to_dump, inode_offset_to_dump;
45 static ext2_ino_t       inode_to_dump;
46
47 struct journal_source
48 {
49         enum journal_location where;
50         int fd;
51         ext2_file_t file;
52 };
53
54 static void dump_journal(char *, FILE *, struct journal_source *);
55
56 static void dump_descriptor_block(FILE *, struct journal_source *,
57                                   char *, journal_superblock_t *,
58                                   unsigned int *, int, tid_t);
59
60 static void dump_revoke_block(FILE *, char *, journal_superblock_t *,
61                                   unsigned int, int, tid_t);
62
63 static void dump_metadata_block(FILE *, struct journal_source *,
64                                 journal_superblock_t*,
65                                 unsigned int, unsigned int, unsigned int,
66                                 int, tid_t);
67
68 static void do_hexdump (FILE *, char *, int);
69
70 #define WRAP(jsb, blocknr)                                      \
71         if (blocknr >= be32_to_cpu((jsb)->s_maxlen))            \
72                 blocknr -= (be32_to_cpu((jsb)->s_maxlen) -      \
73                             be32_to_cpu((jsb)->s_first));
74
75 void do_logdump(int argc, char **argv)
76 {
77         int             c;
78         int             retval;
79         char            *out_fn;
80         FILE            *out_file;
81
82         char            *inode_spec = NULL;
83         char            *journal_fn = NULL;
84         int             journal_fd = 0;
85         int             use_sb = 0;
86         ext2_ino_t      journal_inum;
87         struct ext2_inode journal_inode;
88         ext2_file_t     journal_file;
89         char            *tmp;
90         struct journal_source journal_source;
91         struct ext2_super_block *es = NULL;
92
93         journal_source.where = JOURNAL_IS_INTERNAL;
94         journal_source.fd = 0;
95         journal_source.file = 0;
96         dump_all = 0;
97         dump_old = 0;
98         dump_contents = 0;
99         dump_descriptors = 1;
100         block_to_dump = ANY_BLOCK;
101         bitmap_to_dump = -1;
102         inode_block_to_dump = ANY_BLOCK;
103         inode_to_dump = -1;
104
105         reset_getopt();
106         while ((c = getopt (argc, argv, "ab:ci:f:Os")) != EOF) {
107                 switch (c) {
108                 case 'a':
109                         dump_all++;
110                         break;
111                 case 'b':
112                         block_to_dump = strtoul(optarg, &tmp, 0);
113                         if (*tmp) {
114                                 com_err(argv[0], 0,
115                                         "Bad block number - %s", optarg);
116                                 return;
117                         }
118                         dump_descriptors = 0;
119                         break;
120                 case 'c':
121                         dump_contents++;
122                         break;
123                 case 'f':
124                         journal_fn = optarg;
125                         break;
126                 case 'i':
127                         inode_spec = optarg;
128                         dump_descriptors = 0;
129                         break;
130                 case 'O':
131                         dump_old++;
132                         break;
133                 case 's':
134                         use_sb++;
135                         break;
136                 default:
137                         goto print_usage;
138                 }
139         }
140         if (optind != argc && optind != argc-1) {
141                 goto print_usage;
142         }
143
144         if (current_fs)
145                 es = current_fs->super;
146
147         if (inode_spec) {
148                 int inode_group, group_offset, inodes_per_block;
149
150                 if (check_fs_open(argv[0]))
151                         return;
152
153                 inode_to_dump = string_to_inode(inode_spec);
154                 if (!inode_to_dump)
155                         return;
156
157                 inode_group = ((inode_to_dump - 1)
158                                / es->s_inodes_per_group);
159                 group_offset = ((inode_to_dump - 1)
160                                 % es->s_inodes_per_group);
161                 inodes_per_block = (current_fs->blocksize
162                                     / sizeof(struct ext2_inode));
163
164                 inode_block_to_dump =
165                         ext2fs_inode_table_loc(current_fs, inode_group) +
166                         (group_offset / inodes_per_block);
167                 inode_offset_to_dump = ((group_offset % inodes_per_block)
168                                         * sizeof(struct ext2_inode));
169                 printf("Inode %u is at group %u, block %llu, offset %u\n",
170                        inode_to_dump, inode_group,
171                        inode_block_to_dump, inode_offset_to_dump);
172         }
173
174         if (optind == argc) {
175                 out_file = stdout;
176         } else {
177                 out_fn = argv[optind];
178                 out_file = fopen(out_fn, "w");
179                 if (!out_file) {
180                         com_err(argv[0], errno, "while opening %s for logdump",
181                                 out_fn);
182                         goto errout;
183                 }
184         }
185
186         if (block_to_dump != ANY_BLOCK && current_fs != NULL) {
187                 group_to_dump = ((block_to_dump -
188                                   es->s_first_data_block)
189                                  / es->s_blocks_per_group);
190                 bitmap_to_dump = ext2fs_block_bitmap_loc(current_fs, group_to_dump);
191         }
192
193         if (!journal_fn && check_fs_open(argv[0]))
194                 goto errout;
195
196         if (journal_fn) {
197                 /* Set up to read journal from a regular file somewhere */
198                 journal_fd = open(journal_fn, O_RDONLY, 0);
199                 if (journal_fd < 0) {
200                         com_err(argv[0], errno, "while opening %s for logdump",
201                                 journal_fn);
202                         goto errout;
203                 }
204
205                 journal_source.where = JOURNAL_IS_EXTERNAL;
206                 journal_source.fd = journal_fd;
207         } else if ((journal_inum = es->s_journal_inum)) {
208                 if (use_sb) {
209                         if (es->s_jnl_backup_type != EXT3_JNL_BACKUP_BLOCKS) {
210                                 com_err(argv[0], 0,
211                                         "no journal backup in super block\n");
212                                 goto errout;
213                         }
214                         memset(&journal_inode, 0, sizeof(struct ext2_inode));
215                         memcpy(&journal_inode.i_block[0], es->s_jnl_blocks,
216                                EXT2_N_BLOCKS*4);
217                         journal_inode.i_size_high = es->s_jnl_blocks[15];
218                         journal_inode.i_size = es->s_jnl_blocks[16];
219                         journal_inode.i_links_count = 1;
220                         journal_inode.i_mode = LINUX_S_IFREG | 0600;
221                 } else {
222                         if (debugfs_read_inode(journal_inum, &journal_inode,
223                                                argv[0]))
224                                 goto errout;
225                 }
226
227                 retval = ext2fs_file_open2(current_fs, journal_inum,
228                                            &journal_inode, 0, &journal_file);
229                 if (retval) {
230                         com_err(argv[0], retval, "while opening ext2 file");
231                         goto errout;
232                 }
233                 journal_source.where = JOURNAL_IS_INTERNAL;
234                 journal_source.file = journal_file;
235         } else {
236                 char uuid[37];
237
238                 uuid_unparse(es->s_journal_uuid, uuid);
239                 journal_fn = blkid_get_devname(NULL, "UUID", uuid);
240                 if (!journal_fn)
241                                 journal_fn = blkid_devno_to_devname(es->s_journal_dev);
242                 if (!journal_fn) {
243                         com_err(argv[0], 0, "filesystem has no journal");
244                         goto errout;
245                 }
246                 journal_fd = open(journal_fn, O_RDONLY, 0);
247                 if (journal_fd < 0) {
248                         com_err(argv[0], errno, "while opening %s for logdump",
249                                 journal_fn);
250                         free(journal_fn);
251                         goto errout;
252                 }
253                 fprintf(out_file, "Using external journal found at %s\n",
254                         journal_fn);
255                 free(journal_fn);
256                 journal_source.where = JOURNAL_IS_EXTERNAL;
257                 journal_source.fd = journal_fd;
258         }
259
260         dump_journal(argv[0], out_file, &journal_source);
261
262         if (journal_source.where == JOURNAL_IS_INTERNAL)
263                 ext2fs_file_close(journal_file);
264         else
265                 close(journal_fd);
266
267 errout:
268         if (out_file && (out_file != stdout))
269                 fclose(out_file);
270
271         return;
272
273 print_usage:
274         fprintf(stderr, "%s: Usage: logdump [-acsO] [-b<block>] [-i<filespec>]\n\t"
275                 "[-f<journal_file>] [output_file]\n", argv[0]);
276 }
277
278
279 static int read_journal_block(const char *cmd, struct journal_source *source,
280                               off_t offset, char *buf, unsigned int size)
281 {
282         int retval;
283         unsigned int got;
284
285         if (source->where == JOURNAL_IS_EXTERNAL) {
286                 if (lseek(source->fd, offset, SEEK_SET) < 0) {
287                         retval = errno;
288                         goto seek_err;
289                 }
290                 retval = read(source->fd, buf, size);
291                 if (retval < 0) {
292                         retval = errno;
293                         goto read_err;
294                 }
295                 got = retval;
296                 retval = 0;
297         } else {
298                 retval = ext2fs_file_lseek(source->file, offset,
299                                            EXT2_SEEK_SET, NULL);
300                 if (retval) {
301                 seek_err:
302                         com_err(cmd, retval, "while seeking in reading journal");
303                         return retval;
304                 }
305                 retval = ext2fs_file_read(source->file, buf, size, &got);
306                 if (retval) {
307                 read_err:
308                         com_err(cmd, retval, "while reading journal");
309                         return retval;
310                 }
311         }
312         if (got != size) {
313                 com_err(cmd, 0, "short read (read %u, expected %u) "
314                         "while reading journal", got, size);
315                 retval = -1;
316         }
317         return retval;
318 }
319
320 static const char *type_to_name(int btype)
321 {
322         switch (btype) {
323         case JFS_DESCRIPTOR_BLOCK:
324                 return "descriptor block";
325         case JFS_COMMIT_BLOCK:
326                 return "commit block";
327         case JFS_SUPERBLOCK_V1:
328                 return "V1 superblock";
329         case JFS_SUPERBLOCK_V2:
330                 return "V2 superblock";
331         case JFS_REVOKE_BLOCK:
332                 return "revoke table";
333         }
334         return "unrecognised type";
335 }
336
337
338 static void dump_journal(char *cmdname, FILE *out_file,
339                          struct journal_source *source)
340 {
341         struct ext2_super_block *sb;
342         char                    jsb_buffer[1024];
343         char                    buf[8192];
344         journal_superblock_t    *jsb;
345         unsigned int            blocksize = 1024;
346         int                     retval;
347         __u32                   magic, sequence, blocktype;
348         journal_header_t        *header;
349
350         tid_t                   transaction;
351         unsigned int            blocknr = 0;
352
353         /* First, check to see if there's an ext2 superblock header */
354         retval = read_journal_block(cmdname, source, 0, buf, 2048);
355         if (retval)
356                 return;
357
358         jsb = (journal_superblock_t *) buf;
359         sb = (struct ext2_super_block *) (buf+1024);
360 #ifdef WORDS_BIGENDIAN
361         if (sb->s_magic == ext2fs_swab16(EXT2_SUPER_MAGIC))
362                 ext2fs_swap_super(sb);
363 #endif
364
365         if ((be32_to_cpu(jsb->s_header.h_magic) != JFS_MAGIC_NUMBER) &&
366             (sb->s_magic == EXT2_SUPER_MAGIC) &&
367             ext2fs_has_feature_journal_dev(sb)) {
368                 blocksize = EXT2_BLOCK_SIZE(sb);
369                 blocknr = (blocksize == 1024) ? 2 : 1;
370                 uuid_unparse(sb->s_uuid, jsb_buffer);
371                 fprintf(out_file, "Ext2 superblock header found.\n");
372                 if (dump_all) {
373                         fprintf(out_file, "\tuuid=%s\n", jsb_buffer);
374                         fprintf(out_file, "\tblocksize=%d\n", blocksize);
375                         fprintf(out_file, "\tjournal data size %lu\n",
376                                 (unsigned long) ext2fs_blocks_count(sb));
377                 }
378         }
379
380         /* Next, read the journal superblock */
381
382         retval = read_journal_block(cmdname, source, blocknr*blocksize,
383                                     jsb_buffer, 1024);
384         if (retval)
385                 return;
386
387         jsb = (journal_superblock_t *) jsb_buffer;
388         if (be32_to_cpu(jsb->s_header.h_magic) != JFS_MAGIC_NUMBER) {
389                 fprintf(out_file,
390                         "Journal superblock magic number invalid!\n");
391                 return;
392         }
393         blocksize = be32_to_cpu(jsb->s_blocksize);
394         transaction = be32_to_cpu(jsb->s_sequence);
395         blocknr = be32_to_cpu(jsb->s_start);
396
397         fprintf(out_file, "Journal starts at block %u, transaction %u\n",
398                 blocknr, transaction);
399
400         if (!blocknr) {
401                 /* Empty journal, nothing to do. */
402                 if (!dump_old)
403                         return;
404                 else
405                         blocknr = 1;
406         }
407
408         while (1) {
409                 retval = read_journal_block(cmdname, source,
410                                             blocknr*blocksize, buf,
411                                             blocksize);
412                 if (retval)
413                         return;
414
415                 header = (journal_header_t *) buf;
416
417                 magic = be32_to_cpu(header->h_magic);
418                 sequence = be32_to_cpu(header->h_sequence);
419                 blocktype = be32_to_cpu(header->h_blocktype);
420
421                 if (magic != JFS_MAGIC_NUMBER) {
422                         fprintf (out_file, "No magic number at block %u: "
423                                  "end of journal.\n", blocknr);
424                         return;
425                 }
426
427                 if (sequence != transaction) {
428                         fprintf (out_file, "Found sequence %u (not %u) at "
429                                  "block %u: end of journal.\n",
430                                  sequence, transaction, blocknr);
431                         if (!dump_old)
432                                 return;
433                 }
434
435                 if (dump_descriptors) {
436                         fprintf (out_file, "Found expected sequence %u, "
437                                  "type %u (%s) at block %u\n",
438                                  sequence, blocktype,
439                                  type_to_name(blocktype), blocknr);
440                 }
441
442                 switch (blocktype) {
443                 case JFS_DESCRIPTOR_BLOCK:
444                         dump_descriptor_block(out_file, source, buf, jsb,
445                                               &blocknr, blocksize,
446                                               transaction);
447                         continue;
448
449                 case JFS_COMMIT_BLOCK:
450                         transaction++;
451                         blocknr++;
452                         WRAP(jsb, blocknr);
453                         continue;
454
455                 case JFS_REVOKE_BLOCK:
456                         dump_revoke_block(out_file, buf, jsb,
457                                           blocknr, blocksize,
458                                           transaction);
459                         blocknr++;
460                         WRAP(jsb, blocknr);
461                         continue;
462
463                 default:
464                         fprintf (out_file, "Unexpected block type %u at "
465                                  "block %u.\n", blocktype, blocknr);
466                         return;
467                 }
468         }
469 }
470
471 static inline size_t journal_super_tag_bytes(journal_superblock_t *jsb)
472 {
473         size_t sz;
474
475         if (JSB_HAS_INCOMPAT_FEATURE(jsb, JFS_FEATURE_INCOMPAT_CSUM_V3))
476                 return sizeof(journal_block_tag3_t);
477
478         sz = sizeof(journal_block_tag_t);
479
480         if (JSB_HAS_INCOMPAT_FEATURE(jsb, JFS_FEATURE_INCOMPAT_CSUM_V2))
481                 sz += sizeof(__u16);
482
483         if (JSB_HAS_INCOMPAT_FEATURE(jsb, JFS_FEATURE_INCOMPAT_64BIT))
484                 return sz;
485
486         return sz - sizeof(__u32);
487 }
488
489 static void dump_descriptor_block(FILE *out_file,
490                                   struct journal_source *source,
491                                   char *buf,
492                                   journal_superblock_t *jsb,
493                                   unsigned int *blockp, int blocksize,
494                                   tid_t transaction)
495 {
496         int                     offset, tag_size, csum_size = 0;
497         char                    *tagp;
498         journal_block_tag_t     *tag;
499         unsigned int            blocknr;
500         __u32                   tag_block;
501         __u32                   tag_flags;
502
503         tag_size = journal_super_tag_bytes(jsb);
504         offset = sizeof(journal_header_t);
505         blocknr = *blockp;
506
507         if (JSB_HAS_INCOMPAT_FEATURE(jsb, JFS_FEATURE_INCOMPAT_CSUM_V3) ||
508             JSB_HAS_INCOMPAT_FEATURE(jsb, JFS_FEATURE_INCOMPAT_CSUM_V2))
509                 csum_size = sizeof(struct journal_block_tail);
510
511         if (dump_all)
512                 fprintf(out_file, "Dumping descriptor block, sequence %u, at "
513                         "block %u:\n", transaction, blocknr);
514
515         ++blocknr;
516         WRAP(jsb, blocknr);
517
518         do {
519                 /* Work out the location of the current tag, and skip to
520                  * the next one... */
521                 tagp = &buf[offset];
522                 tag = (journal_block_tag_t *) tagp;
523                 offset += tag_size;
524
525                 /* ... and if we have gone too far, then we've reached the
526                    end of this block. */
527                 if (offset > blocksize - csum_size)
528                         break;
529
530                 tag_block = be32_to_cpu(tag->t_blocknr);
531                 tag_flags = be16_to_cpu(tag->t_flags);
532
533                 if (!(tag_flags & JFS_FLAG_SAME_UUID))
534                         offset += 16;
535
536                 dump_metadata_block(out_file, source, jsb,
537                                     blocknr, tag_block, tag_flags, blocksize,
538                                     transaction);
539
540                 ++blocknr;
541                 WRAP(jsb, blocknr);
542
543         } while (!(tag_flags & JFS_FLAG_LAST_TAG));
544
545         *blockp = blocknr;
546 }
547
548
549 static void dump_revoke_block(FILE *out_file, char *buf,
550                               journal_superblock_t *jsb EXT2FS_ATTR((unused)),
551                               unsigned int blocknr,
552                               int blocksize EXT2FS_ATTR((unused)),
553                               tid_t transaction)
554 {
555         int                     offset, max;
556         journal_revoke_header_t *header;
557         unsigned long long      rblock;
558         int                     tag_size = sizeof(__u32);
559
560         if (dump_all)
561                 fprintf(out_file, "Dumping revoke block, sequence %u, at "
562                         "block %u:\n", transaction, blocknr);
563
564         if (be32_to_cpu(jsb->s_feature_incompat) & JFS_FEATURE_INCOMPAT_64BIT)
565                 tag_size = sizeof(__u64);
566
567         header = (journal_revoke_header_t *) buf;
568         offset = sizeof(journal_revoke_header_t);
569         max = be32_to_cpu(header->r_count);
570
571         while (offset < max) {
572                 if (tag_size == sizeof(__u32)) {
573                         __u32 *entry = (__u32 *) (buf + offset);
574                         rblock = be32_to_cpu(*entry);
575                 } else {
576                         __u64 *entry = (__u64 *) (buf + offset);
577                         rblock = ext2fs_be64_to_cpu(*entry);
578                 }
579                 if (dump_all || rblock == block_to_dump) {
580                         fprintf(out_file, "  Revoke FS block %llu", rblock);
581                         if (dump_all)
582                                 fprintf(out_file, "\n");
583                         else
584                                 fprintf(out_file," at block %u, sequence %u\n",
585                                         blocknr, transaction);
586                 }
587                 offset += tag_size;
588         }
589 }
590
591
592 static void show_extent(FILE *out_file, int start_extent, int end_extent,
593                         __u32 first_block)
594 {
595         if (start_extent >= 0 && first_block != 0)
596                 fprintf(out_file, "(%d+%u): %u ",
597                         start_extent, end_extent-start_extent, first_block);
598 }
599
600 static void show_indirect(FILE *out_file, const char *name, __u32 where)
601 {
602         if (where)
603                 fprintf(out_file, "(%s): %u ", name, where);
604 }
605
606
607 static void dump_metadata_block(FILE *out_file, struct journal_source *source,
608                                 journal_superblock_t *jsb EXT2FS_ATTR((unused)),
609                                 unsigned int log_blocknr,
610                                 unsigned int fs_blocknr,
611                                 unsigned int log_tag_flags,
612                                 int blocksize,
613                                 tid_t transaction)
614 {
615         int             retval;
616         char            buf[8192];
617
618         if (!(dump_all
619               || (fs_blocknr == block_to_dump)
620               || (fs_blocknr == inode_block_to_dump)
621               || (fs_blocknr == bitmap_to_dump)))
622                 return;
623
624         fprintf(out_file, "  FS block %u logged at ", fs_blocknr);
625         if (!dump_all)
626                 fprintf(out_file, "sequence %u, ", transaction);
627         fprintf(out_file, "journal block %u (flags 0x%x)\n", log_blocknr,
628                 log_tag_flags);
629
630         /* There are two major special cases to parse:
631          *
632          * If this block is a block
633          * bitmap block, we need to give it special treatment so that we
634          * can log any allocates and deallocates which affect the
635          * block_to_dump query block.
636          *
637          * If the block is an inode block for the inode being searched
638          * for, then we need to dump the contents of that inode
639          * structure symbolically.
640          */
641
642         if (!(dump_contents && dump_all)
643             && fs_blocknr != block_to_dump
644             && fs_blocknr != bitmap_to_dump
645             && fs_blocknr != inode_block_to_dump)
646                 return;
647
648         retval = read_journal_block("logdump", source,
649                                     blocksize * log_blocknr,
650                                     buf, blocksize);
651         if (retval)
652                 return;
653
654         if (fs_blocknr == bitmap_to_dump) {
655                 struct ext2_super_block *super;
656                 int offset;
657
658                 super = current_fs->super;
659                 offset = ((block_to_dump - super->s_first_data_block) %
660                           super->s_blocks_per_group);
661
662                 fprintf(out_file, "    (block bitmap for block %llu: "
663                         "block is %s)\n",
664                         block_to_dump,
665                         ext2fs_test_bit(offset, buf) ? "SET" : "CLEAR");
666         }
667
668         if (fs_blocknr == inode_block_to_dump) {
669                 struct ext2_inode *inode;
670                 int first, prev, this, start_extent, i;
671
672                 fprintf(out_file, "    (inode block for inode %u):\n",
673                         inode_to_dump);
674
675                 inode = (struct ext2_inode *) (buf + inode_offset_to_dump);
676                 internal_dump_inode(out_file, "    ", inode_to_dump, inode, 0);
677
678                 /* Dump out the direct/indirect blocks here:
679                  * internal_dump_inode can only dump them from the main
680                  * on-disk inode, not from the journaled copy of the
681                  * inode. */
682
683                 fprintf (out_file, "    Blocks:  ");
684                 first = prev = start_extent = -1;
685
686                 for (i=0; i<EXT2_NDIR_BLOCKS; i++) {
687                         this = inode->i_block[i];
688                         if (start_extent >= 0  && this == prev+1) {
689                                 prev = this;
690                                 continue;
691                         } else {
692                                 show_extent(out_file, start_extent, i, first);
693                                 start_extent = i;
694                                 first = prev = this;
695                         }
696                 }
697                 show_extent(out_file, start_extent, i, first);
698                 show_indirect(out_file, "IND", inode->i_block[i++]);
699                 show_indirect(out_file, "DIND", inode->i_block[i++]);
700                 show_indirect(out_file, "TIND", inode->i_block[i++]);
701
702                 fprintf(out_file, "\n");
703         }
704
705         if (dump_contents)
706                 do_hexdump(out_file, buf, blocksize);
707
708 }
709
710 static void do_hexdump (FILE *out_file, char *buf, int blocksize)
711 {
712         int i,j;
713         int *intp;
714         char *charp;
715         unsigned char c;
716
717         intp = (int *) buf;
718         charp = (char *) buf;
719
720         for (i=0; i<blocksize; i+=16) {
721                 fprintf(out_file, "    %04x:  ", i);
722                 for (j=0; j<16; j+=4)
723                         fprintf(out_file, "%08x ", *intp++);
724                 for (j=0; j<16; j++) {
725                         c = *charp++;
726                         if (c < ' ' || c >= 127)
727                                 c = '.';
728                         fprintf(out_file, "%c", c);
729                 }
730                 fprintf(out_file, "\n");
731         }
732 }
733