util-linux/hexdump.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * hexdump implementation for busybox
   4  * Based on code from util-linux v 2.11l
   5  *
   6  * Copyright (c) 1989
   7  * The Regents of the University of California.  All rights reserved.
   8  *
   9  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  10  */
  11
  12 //usage:#define hexdump_trivial_usage
  13 //usage:       "[-bcCdefnosvx" IF_FEATURE_HEXDUMP_REVERSE("R") "] [FILE]..."
  14 //usage:#define hexdump_full_usage "\n\n"
  15 //usage:       "Display FILEs (or stdin) in a user specified format\n"
  16 //usage:     "\nOptions:"
  17 //usage:     "\n        -b              One-byte octal display"
  18 //usage:     "\n        -c              One-byte character display"
  19 //usage:     "\n        -C              Canonical hex+ASCII, 16 bytes per line"
  20 //usage:     "\n        -d              Two-byte decimal display"
  21 //usage:     "\n        -e FORMAT_STRING"
  22 //usage:     "\n        -f FORMAT_FILE"
  23 //usage:     "\n        -n LENGTH       Interpret only LENGTH bytes of input"
  24 //usage:     "\n        -o              Two-byte octal display"
  25 //usage:     "\n        -s OFFSET       Skip OFFSET bytes"
  26 //usage:     "\n        -v              Display all input data"
  27 //usage:     "\n        -x              Two-byte hexadecimal display"
  28 //usage:        IF_FEATURE_HEXDUMP_REVERSE(
  29 //usage:     "\n        -R              Reverse of 'hexdump -Cv'")
  30 //usage:
  31 //usage:#define hd_trivial_usage
  32 //usage:       "FILE..."
  33 //usage:#define hd_full_usage "\n\n"
  34 //usage:       "hd is an alias for hexdump -C"
  35
  36 #include "libbb.h"
  37 #include "dump.h"
  38
  39 /* This is a NOEXEC applet. Be very careful! */
  40
  41 static void bb_dump_addfile(dumper_t *dumper, char *name)
  42 {
  43         char *p;
  44         FILE *fp;
  45         char *buf;
  46
  47         fp = xfopen_for_read(name);
  48         while ((buf = xmalloc_fgetline(fp)) != NULL) {
  49                 p = skip_whitespace(buf);
  50                 if (*p && (*p != '#')) {
  51                         bb_dump_add(dumper, p);
  52                 }
  53                 free(buf);
  54         }
  55         fclose(fp);
  56 }
  57
  58 static const char *const add_strings[] = {
  59         "\"%07.7_ax \" 16/1 \"%03o \" \"\\n\"",   /* b */
  60         "\"%07.7_ax \" 16/1 \"%3_c \" \"\\n\"",   /* c */
  61         "\"%07.7_ax \" 8/2 \"  %05u \" \"\\n\"",  /* d */
  62         "\"%07.7_ax \" 8/2 \" %06o \" \"\\n\"",   /* o */
  63         "\"%07.7_ax \" 8/2 \"   %04x \" \"\\n\"", /* x */
  64 };
  65
  66 static const char add_first[] ALIGN1 = "\"%07.7_Ax\n\"";
  67
  68 static const char hexdump_opts[] ALIGN1 = "bcdoxCe:f:n:s:v" IF_FEATURE_HEXDUMP_REVERSE("R");
  69
  70 static const struct suffix_mult suffixes[] = {
  71         { "b", 512 },
  72         { "k", 1024 },
  73         { "m", 1024*1024 },
  74         { "", 0 }
  75 };
  76
  77 int hexdump_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
  78 int hexdump_main(int argc, char **argv)
  79 {
  80         dumper_t *dumper = alloc_dumper();
  81         const char *p;
  82         int ch;
  83 #if ENABLE_FEATURE_HEXDUMP_REVERSE
  84         FILE *fp;
  85         smallint rdump = 0;
  86 #endif
  87
  88         if (ENABLE_HD && !applet_name[2]) { /* we are "hd" */
  89                 ch = 'C';
  90                 goto hd_applet;
  91         }
  92
  93         /* We cannot use getopt32: in hexdump options are cumulative.
  94          * E.g. "hexdump -C -C file" should dump each line twice */
  95         while ((ch = getopt(argc, argv, hexdump_opts)) > 0) {
  96                 p = strchr(hexdump_opts, ch);
  97                 if (!p)
  98                         bb_show_usage();
  99                 if ((p - hexdump_opts) < 5) {
 100                         bb_dump_add(dumper, add_first);
 101                         bb_dump_add(dumper, add_strings[(int)(p - hexdump_opts)]);
 102                 }
 103                 /* Save a little bit of space below by omitting the 'else's. */
 104                 if (ch == 'C') {
 105  hd_applet:
 106                         bb_dump_add(dumper, "\"%08.8_Ax\n\"");
 107                         bb_dump_add(dumper, "\"%08.8_ax  \" 8/1 \"%02x \" \"  \" 8/1 \"%02x \" ");
 108                         bb_dump_add(dumper, "\"  |\" 16/1 \"%_p\" \"|\\n\"");
 109                 }
 110                 if (ch == 'e') {
 111                         bb_dump_add(dumper, optarg);
 112                 } /* else */
 113                 if (ch == 'f') {
 114                         bb_dump_addfile(dumper, optarg);
 115                 } /* else */
 116                 if (ch == 'n') {
 117                         dumper->dump_length = xatoi_positive(optarg);
 118                 } /* else */
 119                 if (ch == 's') { /* compat: -s accepts hex numbers too */
 120                         dumper->dump_skip = xstrtoul_range_sfx(optarg, /*base:*/ 0, /*lo:*/ 0, /*hi:*/ LONG_MAX, suffixes);
 121                 } /* else */
 122                 if (ch == 'v') {
 123                         dumper->dump_vflag = ALL;
 124                 }
 125 #if ENABLE_FEATURE_HEXDUMP_REVERSE
 126                 if (ch == 'R') {
 127                         rdump = 1;
 128                 }
 129 #endif
 130         }
 131
 132         if (!dumper->fshead) {
 133                 bb_dump_add(dumper, add_first);
 134                 bb_dump_add(dumper, "\"%07.7_ax \" 8/2 \"%04x \" \"\\n\"");
 135         }
 136
 137         argv += optind;
 138
 139 #if !ENABLE_FEATURE_HEXDUMP_REVERSE
 140         return bb_dump_dump(dumper, argv);
 141 #else
 142         if (!rdump) {
 143                 return bb_dump_dump(dumper, argv);
 144         }
 145
 146         /* -R: reverse of 'hexdump -Cv' */
 147         fp = stdin;
 148         if (!*argv) {
 149                 argv--;
 150                 goto jump_in;
 151         }
 152
 153         do {
 154                 char *buf;
 155                 fp = xfopen_for_read(*argv);
 156  jump_in:
 157                 while ((buf = xmalloc_fgetline(fp)) != NULL) {
 158                         p = buf;
 159                         while (1) {
 160                                 /* skip address or previous byte */
 161                                 while (isxdigit(*p)) p++;
 162                                 while (*p == ' ') p++;
 163                                 /* '|' char will break the line */
 164                                 if (!isxdigit(*p) || sscanf(p, "%x ", &ch) != 1)
 165                                         break;
 166                                 putchar(ch);
 167                         }
 168                         free(buf);
 169                 }
 170                 fclose(fp);
 171         } while (*++argv);
 172
 173         fflush_stdout_and_exit(EXIT_SUCCESS);
 174 #endif
 175 }