src/md5sum.c

   1 /* Compute checksums of files or strings.
   2    Copyright (C) 1995-2011 Free Software Foundation, Inc.
   3
   4    This program is free software: you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation, either version 3 of the License, or
   7    (at your option) any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
  16
  17 /* Written by Ulrich Drepper <drepper@gnu.ai.mit.edu>.  */
  18
  19 #include <config.h>
  20
  21 #include <getopt.h>
  22 #include <sys/types.h>
  23
  24 #include "system.h"
  25
  26 #if HASH_ALGO_MD5
  27 # include "md5.h"
  28 #endif
  29 #if HASH_ALGO_SHA1
  30 # include "sha1.h"
  31 #endif
  32 #if HASH_ALGO_SHA256 || HASH_ALGO_SHA224
  33 # include "sha256.h"
  34 #endif
  35 #if HASH_ALGO_SHA512 || HASH_ALGO_SHA384
  36 # include "sha512.h"
  37 #endif
  38 #include "error.h"
  39 #include "fadvise.h"
  40 #include "stdio--.h"
  41 #include "xfreopen.h"
  42
  43 /* The official name of this program (e.g., no `g' prefix).  */
  44 #if HASH_ALGO_MD5
  45 # define PROGRAM_NAME "md5sum"
  46 # define DIGEST_TYPE_STRING "MD5"
  47 # define DIGEST_STREAM md5_stream
  48 # define DIGEST_BITS 128
  49 # define DIGEST_REFERENCE "RFC 1321"
  50 # define DIGEST_ALIGN 4
  51 #elif HASH_ALGO_SHA1
  52 # define PROGRAM_NAME "sha1sum"
  53 # define DIGEST_TYPE_STRING "SHA1"
  54 # define DIGEST_STREAM sha1_stream
  55 # define DIGEST_BITS 160
  56 # define DIGEST_REFERENCE "FIPS-180-1"
  57 # define DIGEST_ALIGN 4
  58 #elif HASH_ALGO_SHA256
  59 # define PROGRAM_NAME "sha256sum"
  60 # define DIGEST_TYPE_STRING "SHA256"
  61 # define DIGEST_STREAM sha256_stream
  62 # define DIGEST_BITS 256
  63 # define DIGEST_REFERENCE "FIPS-180-2"
  64 # define DIGEST_ALIGN 4
  65 #elif HASH_ALGO_SHA224
  66 # define PROGRAM_NAME "sha224sum"
  67 # define DIGEST_TYPE_STRING "SHA224"
  68 # define DIGEST_STREAM sha224_stream
  69 # define DIGEST_BITS 224
  70 # define DIGEST_REFERENCE "RFC 3874"
  71 # define DIGEST_ALIGN 4
  72 #elif HASH_ALGO_SHA512
  73 # define PROGRAM_NAME "sha512sum"
  74 # define DIGEST_TYPE_STRING "SHA512"
  75 # define DIGEST_STREAM sha512_stream
  76 # define DIGEST_BITS 512
  77 # define DIGEST_REFERENCE "FIPS-180-2"
  78 # define DIGEST_ALIGN 8
  79 #elif HASH_ALGO_SHA384
  80 # define PROGRAM_NAME "sha384sum"
  81 # define DIGEST_TYPE_STRING "SHA384"
  82 # define DIGEST_STREAM sha384_stream
  83 # define DIGEST_BITS 384
  84 # define DIGEST_REFERENCE "FIPS-180-2"
  85 # define DIGEST_ALIGN 8
  86 #else
  87 # error "Can't decide which hash algorithm to compile."
  88 #endif
  89
  90 #define DIGEST_HEX_BYTES (DIGEST_BITS / 4)
  91 #define DIGEST_BIN_BYTES (DIGEST_BITS / 8)
  92
  93 #define AUTHORS \
  94   proper_name ("Ulrich Drepper"), \
  95   proper_name ("Scott Miller"), \
  96   proper_name ("David Madore")
  97
  98 /* The minimum length of a valid digest line.  This length does
  99    not include any newline character at the end of a line.  */
 100 #define MIN_DIGEST_LINE_LENGTH \
 101   (DIGEST_HEX_BYTES /* length of hexadecimal message digest */ \
 102    + 2 /* blank and binary indicator */ \
 103    + 1 /* minimum filename length */ )
 104
 105 /* True if any of the files read were the standard input. */
 106 static bool have_read_stdin;
 107
 108 /* The minimum length of a valid checksum line for the selected algorithm.  */
 109 static size_t min_digest_line_length;
 110
 111 /* Set to the length of a digest hex string for the selected algorithm.  */
 112 static size_t digest_hex_bytes;
 113
 114 /* With --check, don't generate any output.
 115    The exit code indicates success or failure.  */
 116 static bool status_only = false;
 117
 118 /* With --check, print a message to standard error warning about each
 119    improperly formatted checksum line.  */
 120 static bool warn = false;
 121
 122 /* With --check, suppress the "OK" printed for each verified file.  */
 123 static bool quiet = false;
 124
 125 /* For long options that have no equivalent short option, use a
 126    non-character as a pseudo short option, starting with CHAR_MAX + 1.  */
 127 enum
 128 {
 129   STATUS_OPTION = CHAR_MAX + 1,
 130   QUIET_OPTION
 131 };
 132
 133 static struct option const long_options[] =
 134 {
 135   { "binary", no_argument, NULL, 'b' },
 136   { "check", no_argument, NULL, 'c' },
 137   { "quiet", no_argument, NULL, QUIET_OPTION },
 138   { "status", no_argument, NULL, STATUS_OPTION },
 139   { "text", no_argument, NULL, 't' },
 140   { "warn", no_argument, NULL, 'w' },
 141   { GETOPT_HELP_OPTION_DECL },
 142   { GETOPT_VERSION_OPTION_DECL },
 143   { NULL, 0, NULL, 0 }
 144 };
 145
 146 void
 147 usage (int status)
 148 {
 149   if (status != EXIT_SUCCESS)
 150     fprintf (stderr, _("Try `%s --help' for more information.\n"),
 151              program_name);
 152   else
 153     {
 154       printf (_("\
 155 Usage: %s [OPTION]... [FILE]...\n\
 156 Print or check %s (%d-bit) checksums.\n\
 157 With no FILE, or when FILE is -, read standard input.\n\
 158 \n\
 159 "),
 160               program_name,
 161               DIGEST_TYPE_STRING,
 162               DIGEST_BITS);
 163       if (O_BINARY)
 164         fputs (_("\
 165   -b, --binary         read in binary mode (default unless reading tty stdin)\n\
 166 "), stdout);
 167       else
 168         fputs (_("\
 169   -b, --binary         read in binary mode\n\
 170 "), stdout);
 171       printf (_("\
 172   -c, --check          read %s sums from the FILEs and check them\n"),
 173               DIGEST_TYPE_STRING);
 174       if (O_BINARY)
 175         fputs (_("\
 176   -t, --text           read in text mode (default if reading tty stdin)\n\
 177 "), stdout);
 178       else
 179         fputs (_("\
 180   -t, --text           read in text mode (default)\n\
 181 "), stdout);
 182       fputs (_("\
 183 \n\
 184 The following three options are useful only when verifying checksums:\n\
 185       --quiet          don't print OK for each successfully verified file\n\
 186       --status         don't output anything, status code shows success\n\
 187   -w, --warn           warn about improperly formatted checksum lines\n\
 188 \n\
 189 "), stdout);
 190       fputs (HELP_OPTION_DESCRIPTION, stdout);
 191       fputs (VERSION_OPTION_DESCRIPTION, stdout);
 192       printf (_("\
 193 \n\
 194 The sums are computed as described in %s.  When checking, the input\n\
 195 should be a former output of this program.  The default mode is to print\n\
 196 a line with checksum, a character indicating type (`*' for binary, ` ' for\n\
 197 text), and name for each FILE.\n"),
 198               DIGEST_REFERENCE);
 199       emit_ancillary_info ();
 200     }
 201
 202   exit (status);
 203 }
 204
 205 #define ISWHITE(c) ((c) == ' ' || (c) == '\t')
 206
 207 /* Split the checksum string S (of length S_LEN) from a BSD 'md5' or
 208    'sha1' command into two parts: a hexadecimal digest, and the file
 209    name.  S is modified.  Return true if successful.  */
 210
 211 static bool
 212 bsd_split_3 (char *s, size_t s_len, unsigned char **hex_digest,
 213              char **file_name)
 214 {
 215   size_t i;
 216
 217   if (s_len == 0)
 218     return false;
 219
 220   *file_name = s;
 221
 222   /* Find end of filename. The BSD 'md5' and 'sha1' commands do not escape
 223      filenames, so search backwards for the last ')'. */
 224   i = s_len - 1;
 225   while (i && s[i] != ')')
 226     i--;
 227
 228   if (s[i] != ')')
 229     return false;
 230
 231   s[i++] = '\0';
 232
 233   while (ISWHITE (s[i]))
 234     i++;
 235
 236   if (s[i] != '=')
 237     return false;
 238
 239   i++;
 240
 241   while (ISWHITE (s[i]))
 242     i++;
 243
 244   *hex_digest = (unsigned char *) &s[i];
 245   return true;
 246 }
 247
 248 /* Split the string S (of length S_LEN) into three parts:
 249    a hexadecimal digest, binary flag, and the file name.
 250    S is modified.  Return true if successful.  */
 251
 252 static bool
 253 split_3 (char *s, size_t s_len,
 254          unsigned char **hex_digest, int *binary, char **file_name)
 255 {
 256   bool escaped_filename = false;
 257   size_t algo_name_len;
 258
 259   size_t i = 0;
 260   while (ISWHITE (s[i]))
 261     ++i;
 262
 263   /* Check for BSD-style checksum line. */
 264   algo_name_len = strlen (DIGEST_TYPE_STRING);
 265   if (STREQ_LEN (s + i, DIGEST_TYPE_STRING, algo_name_len))
 266     {
 267       if (s[i + algo_name_len] == ' ')
 268         ++i;
 269       if (s[i + algo_name_len] == '(')
 270         {
 271           *binary = 0;
 272           return bsd_split_3 (s +      i + algo_name_len + 1,
 273                               s_len - (i + algo_name_len + 1),
 274                               hex_digest, file_name);
 275         }
 276     }
 277
 278   /* Ignore this line if it is too short.
 279      Each line must have at least `min_digest_line_length - 1' (or one more, if
 280      the first is a backslash) more characters to contain correct message digest
 281      information.  */
 282   if (s_len - i < min_digest_line_length + (s[i] == '\\'))
 283     return false;
 284
 285   if (s[i] == '\\')
 286     {
 287       ++i;
 288       escaped_filename = true;
 289     }
 290   *hex_digest = (unsigned char *) &s[i];
 291
 292   /* The first field has to be the n-character hexadecimal
 293      representation of the message digest.  If it is not followed
 294      immediately by a white space it's an error.  */
 295   i += digest_hex_bytes;
 296   if (!ISWHITE (s[i]))
 297     return false;
 298
 299   s[i++] = '\0';
 300
 301   if (s[i] != ' ' && s[i] != '*')
 302     return false;
 303   *binary = (s[i++] == '*');
 304
 305   /* All characters between the type indicator and end of line are
 306      significant -- that includes leading and trailing white space.  */
 307   *file_name = &s[i];
 308
 309   if (escaped_filename)
 310     {
 311       /* Translate each `\n' string in the file name to a NEWLINE,
 312          and each `\\' string to a backslash.  */
 313
 314       char *dst = &s[i];
 315
 316       while (i < s_len)
 317         {
 318           switch (s[i])
 319             {
 320             case '\\':
 321               if (i == s_len - 1)
 322                 {
 323                   /* A valid line does not end with a backslash.  */
 324                   return false;
 325                 }
 326               ++i;
 327               switch (s[i++])
 328                 {
 329                 case 'n':
 330                   *dst++ = '\n';
 331                   break;
 332                 case '\\':
 333                   *dst++ = '\\';
 334                   break;
 335                 default:
 336                   /* Only `\' or `n' may follow a backslash.  */
 337                   return false;
 338                 }
 339               break;
 340
 341             case '\0':
 342               /* The file name may not contain a NUL.  */
 343               return false;
 344               break;
 345
 346             default:
 347               *dst++ = s[i++];
 348               break;
 349             }
 350         }
 351       *dst = '\0';
 352     }
 353   return true;
 354 }
 355
 356 /* Return true if S is a NUL-terminated string of DIGEST_HEX_BYTES hex digits.
 357    Otherwise, return false.  */
 358 static bool
 359 hex_digits (unsigned char const *s)
 360 {
 361   unsigned int i;
 362   for (i = 0; i < digest_hex_bytes; i++)
 363     {
 364       if (!isxdigit (*s))
 365         return false;
 366       ++s;
 367     }
 368   return *s == '\0';
 369 }
 370
 371 /* An interface to the function, DIGEST_STREAM.
 372    Operate on FILENAME (it may be "-").
 373
 374    *BINARY indicates whether the file is binary.  BINARY < 0 means it
 375    depends on whether binary mode makes any difference and the file is
 376    a terminal; in that case, clear *BINARY if the file was treated as
 377    text because it was a terminal.
 378
 379    Put the checksum in *BIN_RESULT, which must be properly aligned.
 380    Return true if successful.  */
 381
 382 static bool
 383 digest_file (const char *filename, int *binary, unsigned char *bin_result)
 384 {
 385   FILE *fp;
 386   int err;
 387   bool is_stdin = STREQ (filename, "-");
 388
 389   if (is_stdin)
 390     {
 391       have_read_stdin = true;
 392       fp = stdin;
 393       if (O_BINARY && *binary)
 394         {
 395           if (*binary < 0)
 396             *binary = ! isatty (STDIN_FILENO);
 397           if (*binary)
 398             xfreopen (NULL, "rb", stdin);
 399         }
 400     }
 401   else
 402     {
 403       fp = fopen (filename, (O_BINARY && *binary ? "rb" : "r"));
 404       if (fp == NULL)
 405         {
 406           error (0, errno, "%s", filename);
 407           return false;
 408         }
 409     }
 410
 411   fadvise (fp, FADVISE_SEQUENTIAL);
 412
 413   err = DIGEST_STREAM (fp, bin_result);
 414   if (err)
 415     {
 416       error (0, errno, "%s", filename);
 417       if (fp != stdin)
 418         fclose (fp);
 419       return false;
 420     }
 421
 422   if (!is_stdin && fclose (fp) != 0)
 423     {
 424       error (0, errno, "%s", filename);
 425       return false;
 426     }
 427
 428   return true;
 429 }
 430
 431 static bool
 432 digest_check (const char *checkfile_name)
 433 {
 434   FILE *checkfile_stream;
 435   uintmax_t n_misformatted_lines = 0;
 436   uintmax_t n_properly_formatted_lines = 0;
 437   uintmax_t n_mismatched_checksums = 0;
 438   uintmax_t n_open_or_read_failures = 0;
 439   unsigned char bin_buffer_unaligned[DIGEST_BIN_BYTES + DIGEST_ALIGN];
 440   /* Make sure bin_buffer is properly aligned. */
 441   unsigned char *bin_buffer = ptr_align (bin_buffer_unaligned, DIGEST_ALIGN);
 442   uintmax_t line_number;
 443   char *line;
 444   size_t line_chars_allocated;
 445   bool is_stdin = STREQ (checkfile_name, "-");
 446
 447   if (is_stdin)
 448     {
 449       have_read_stdin = true;
 450       checkfile_name = _("standard input");
 451       checkfile_stream = stdin;
 452     }
 453   else
 454     {
 455       checkfile_stream = fopen (checkfile_name, "r");
 456       if (checkfile_stream == NULL)
 457         {
 458           error (0, errno, "%s", checkfile_name);
 459           return false;
 460         }
 461     }
 462
 463   line_number = 0;
 464   line = NULL;
 465   line_chars_allocated = 0;
 466   do
 467     {
 468       char *filename IF_LINT ( = NULL);
 469       int binary;
 470       unsigned char *hex_digest IF_LINT ( = NULL);
 471       ssize_t line_length;
 472
 473       ++line_number;
 474       if (line_number == 0)
 475         error (EXIT_FAILURE, 0, _("%s: too many checksum lines"),
 476                checkfile_name);
 477
 478       line_length = getline (&line, &line_chars_allocated, checkfile_stream);
 479       if (line_length <= 0)
 480         break;
 481
 482       /* Ignore comment lines, which begin with a '#' character.  */
 483       if (line[0] == '#')
 484         continue;
 485
 486       /* Remove any trailing newline.  */
 487       if (line[line_length - 1] == '\n')
 488         line[--line_length] = '\0';
 489
 490       if (! (split_3 (line, line_length, &hex_digest, &binary, &filename)
 491              && ! (is_stdin && STREQ (filename, "-"))
 492              && hex_digits (hex_digest)))
 493         {
 494           ++n_misformatted_lines;
 495
 496           if (warn)
 497             {
 498               error (0, 0,
 499                      _("%s: %" PRIuMAX
 500                        ": improperly formatted %s checksum line"),
 501                      checkfile_name, line_number,
 502                      DIGEST_TYPE_STRING);
 503             }
 504         }
 505       else
 506         {
 507           static const char bin2hex[] = { '0', '1', '2', '3',
 508                                           '4', '5', '6', '7',
 509                                           '8', '9', 'a', 'b',
 510                                           'c', 'd', 'e', 'f' };
 511           bool ok;
 512
 513           ++n_properly_formatted_lines;
 514
 515           ok = digest_file (filename, &binary, bin_buffer);
 516
 517           if (!ok)
 518             {
 519               ++n_open_or_read_failures;
 520               if (!status_only)
 521                 {
 522                   printf (_("%s: FAILED open or read\n"), filename);
 523                 }
 524             }
 525           else
 526             {
 527               size_t digest_bin_bytes = digest_hex_bytes / 2;
 528               size_t cnt;
 529               /* Compare generated binary number with text representation
 530                  in check file.  Ignore case of hex digits.  */
 531               for (cnt = 0; cnt < digest_bin_bytes; ++cnt)
 532                 {
 533                   if (tolower (hex_digest[2 * cnt])
 534                       != bin2hex[bin_buffer[cnt] >> 4]
 535                       || (tolower (hex_digest[2 * cnt + 1])
 536                           != (bin2hex[bin_buffer[cnt] & 0xf])))
 537                     break;
 538                 }
 539               if (cnt != digest_bin_bytes)
 540                 ++n_mismatched_checksums;
 541
 542               if (!status_only)
 543                 {
 544                   if (cnt != digest_bin_bytes)
 545                     printf ("%s: %s\n", filename, _("FAILED"));
 546                   else if (!quiet)
 547                     printf ("%s: %s\n", filename, _("OK"));
 548                 }
 549             }
 550         }
 551     }
 552   while (!feof (checkfile_stream) && !ferror (checkfile_stream));
 553
 554   free (line);
 555
 556   if (ferror (checkfile_stream))
 557     {
 558       error (0, 0, _("%s: read error"), checkfile_name);
 559       return false;
 560     }
 561
 562   if (!is_stdin && fclose (checkfile_stream) != 0)
 563     {
 564       error (0, errno, "%s", checkfile_name);
 565       return false;
 566     }
 567
 568   if (n_properly_formatted_lines == 0)
 569     {
 570       /* Warn if no tests are found.  */
 571       error (0, 0, _("%s: no properly formatted %s checksum lines found"),
 572              checkfile_name, DIGEST_TYPE_STRING);
 573     }
 574   else
 575     {
 576       if (!status_only)
 577         {
 578           if (n_misformatted_lines != 0)
 579             error (0, 0,
 580                    (ngettext
 581                     ("WARNING: %" PRIuMAX " line is improperly formatted",
 582                      "WARNING: %" PRIuMAX " lines are improperly formatted",
 583                      select_plural (n_misformatted_lines))),
 584                    n_misformatted_lines);
 585
 586           if (n_open_or_read_failures != 0)
 587             error (0, 0,
 588                    (ngettext
 589                     ("WARNING: %" PRIuMAX " listed file could not be read",
 590                      "WARNING: %" PRIuMAX " listed files could not be read",
 591                      select_plural (n_open_or_read_failures))),
 592                    n_open_or_read_failures);
 593
 594           if (n_mismatched_checksums != 0)
 595             error (0, 0,
 596                    (ngettext
 597                     ("WARNING: %" PRIuMAX " computed checksum did NOT match",
 598                      "WARNING: %" PRIuMAX " computed checksums did NOT match",
 599                      select_plural (n_mismatched_checksums))),
 600                    n_mismatched_checksums);
 601         }
 602     }
 603
 604   return (n_properly_formatted_lines != 0
 605           && n_mismatched_checksums == 0
 606           && n_open_or_read_failures == 0);
 607 }
 608
 609 int
 610 main (int argc, char **argv)
 611 {
 612   unsigned char bin_buffer_unaligned[DIGEST_BIN_BYTES + DIGEST_ALIGN];
 613   /* Make sure bin_buffer is properly aligned. */
 614   unsigned char *bin_buffer = ptr_align (bin_buffer_unaligned, DIGEST_ALIGN);
 615   bool do_check = false;
 616   int opt;
 617   bool ok = true;
 618   int binary = -1;
 619
 620   /* Setting values of global variables.  */
 621   initialize_main (&argc, &argv);
 622   set_program_name (argv[0]);
 623   setlocale (LC_ALL, "");
 624   bindtextdomain (PACKAGE, LOCALEDIR);
 625   textdomain (PACKAGE);
 626
 627   atexit (close_stdout);
 628
 629   /* Line buffer stdout to ensure lines are written atomically and immediately
 630      so that processes running in parallel do not intersperse their output.  */
 631   setvbuf (stdout, NULL, _IOLBF, 0);
 632
 633   while ((opt = getopt_long (argc, argv, "bctw", long_options, NULL)) != -1)
 634     switch (opt)
 635       {
 636       case 'b':
 637         binary = 1;
 638         break;
 639       case 'c':
 640         do_check = true;
 641         break;
 642       case STATUS_OPTION:
 643         status_only = true;
 644         warn = false;
 645         quiet = false;
 646         break;
 647       case 't':
 648         binary = 0;
 649         break;
 650       case 'w':
 651         status_only = false;
 652         warn = true;
 653         quiet = false;
 654         break;
 655       case QUIET_OPTION:
 656         status_only = false;
 657         warn = false;
 658         quiet = true;
 659         break;
 660       case_GETOPT_HELP_CHAR;
 661       case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
 662       default:
 663         usage (EXIT_FAILURE);
 664       }
 665
 666   min_digest_line_length = MIN_DIGEST_LINE_LENGTH;
 667   digest_hex_bytes = DIGEST_HEX_BYTES;
 668
 669   if (0 <= binary && do_check)
 670     {
 671       error (0, 0, _("the --binary and --text options are meaningless when "
 672                      "verifying checksums"));
 673       usage (EXIT_FAILURE);
 674     }
 675
 676   if (status_only && !do_check)
 677     {
 678       error (0, 0,
 679        _("the --status option is meaningful only when verifying checksums"));
 680       usage (EXIT_FAILURE);
 681     }
 682
 683   if (warn && !do_check)
 684     {
 685       error (0, 0,
 686        _("the --warn option is meaningful only when verifying checksums"));
 687       usage (EXIT_FAILURE);
 688     }
 689
 690   if (quiet && !do_check)
 691     {
 692       error (0, 0,
 693        _("the --quiet option is meaningful only when verifying checksums"));
 694       usage (EXIT_FAILURE);
 695     }
 696
 697   if (!O_BINARY && binary < 0)
 698     binary = 0;
 699
 700   if (optind == argc)
 701     argv[argc++] = bad_cast ("-");
 702
 703   for (; optind < argc; ++optind)
 704     {
 705       char *file = argv[optind];
 706
 707       if (do_check)
 708         ok &= digest_check (file);
 709       else
 710         {
 711           int file_is_binary = binary;
 712
 713           if (! digest_file (file, &file_is_binary, bin_buffer))
 714             ok = false;
 715           else
 716             {
 717               size_t i;
 718
 719               /* Output a leading backslash if the file name contains
 720                  a newline or backslash.  */
 721               if (strchr (file, '\n') || strchr (file, '\\'))
 722                 putchar ('\\');
 723
 724               for (i = 0; i < (digest_hex_bytes / 2); ++i)
 725                 printf ("%02x", bin_buffer[i]);
 726
 727               putchar (' ');
 728               if (file_is_binary)
 729                 putchar ('*');
 730               else
 731                 putchar (' ');
 732
 733               /* Translate each NEWLINE byte to the string, "\\n",
 734                  and each backslash to "\\\\".  */
 735               for (i = 0; i < strlen (file); ++i)
 736                 {
 737                   switch (file[i])
 738                     {
 739                     case '\n':
 740                       fputs ("\\n", stdout);
 741                       break;
 742
 743                     case '\\':
 744                       fputs ("\\\\", stdout);
 745                       break;
 746
 747                     default:
 748                       putchar (file[i]);
 749                       break;
 750                     }
 751                 }
 752               putchar ('\n');
 753             }
 754         }
 755     }
 756
 757   if (have_read_stdin && fclose (stdin) == EOF)
 758     error (EXIT_FAILURE, errno, _("standard input"));
 759
 760   exit (ok ? EXIT_SUCCESS : EXIT_FAILURE);
 761 }