grep.c

linux平台中

 finish_grep:
  done_on_match -= not_text;
  out_quiet -= not_text;
  if ((not_text & ~out_quiet) && nlines != 0)
    printf (_("Binary file %s matches\n"), filename);
  return nlines;
}

static int
grepfile (char const *file, struct stats *stats)
{
  int desc;
  int count;
  int status;

  if (! file)
    {
      desc = 0;
      filename = label ? label : _("(standard input)");
    }
  else
    {
      while ((desc = open (file, O_RDONLY)) < 0 && errno == EINTR)
	continue;

      if (desc < 0)
	{
	  int e = errno;

	  if (is_EISDIR (e, file) && directories == RECURSE_DIRECTORIES)
	    {
	      if (stat (file, &stats->stat) != 0)
		{
		  error (0, errno, "%s", file);
		  return 1;
		}

	      return grepdir (file, stats);
	    }

	  if (!suppress_errors)
	    {
	      if (directories == SKIP_DIRECTORIES)
		switch (e)
		  {
#if defined(EISDIR)
		  case EISDIR:
		    return 1;
#endif
		  case EACCES:
		    /* When skipping directories, don't worry about
		       directories that can't be opened.  */
		    if (isdir (file))
		      return 1;
		    break;
		  }
	    }

	  suppressible_error (file, e);
	  return 1;
	}

      filename = file;
    }

#if defined(SET_BINARY)
  /* Set input to binary mode.  Pipes are simulated with files
     on DOS, so this includes the case of "foo | grep bar".  */
  if (!isatty (desc))
    SET_BINARY (desc);
#endif

  count = grep (desc, file, stats);
  if (count < 0)
    status = count + 2;
  else
    {
      if (count_matches)
	{
	  if (out_file)
	    printf ("%s%c", filename, ':' & filename_mask);
	  printf ("%d\n", count);
	}

      status = !count;
      if (list_files == 1 - 2 * status)
	printf ("%s%c", filename, '\n' & filename_mask);

      if (! file)
	{
	  off_t required_offset = outleft ? bufoffset : after_last_match;
	  if ((bufmapped || required_offset != bufoffset)
	      && lseek (desc, required_offset, SEEK_SET) < 0
	      && S_ISREG (stats->stat.st_mode))
	    error (0, errno, "%s", filename);
	}
      else
	while (close (desc) != 0)
	  if (errno != EINTR)
	    {
	      error (0, errno, "%s", file);
	      break;
	    }
    }

  return status;
}

static int
grepdir (char const *dir, struct stats const *stats)
{
  int status = 1;
  struct stats const *ancestor;
  char *name_space;

  /* Mingw32 does not support st_ino.  No known working hosts use zero
     for st_ino, so assume that the Mingw32 bug applies if it's zero.  */
  if (stats->stat.st_ino)
    for (ancestor = stats;  (ancestor = ancestor->parent) != 0;  )
      if (ancestor->stat.st_ino == stats->stat.st_ino
	  && ancestor->stat.st_dev == stats->stat.st_dev)
	{
	  if (!suppress_errors)
	    error (0, 0, _("warning: %s: %s\n"), dir,
		   _("recursive directory loop"));
	  return 1;
	}

  name_space = savedir (dir, stats->stat.st_size, included_patterns,
			excluded_patterns);

  if (! name_space)
    {
      if (errno)
	suppressible_error (dir, errno);
      else
	xalloc_die ();
    }
  else
    {
      size_t dirlen = strlen (dir);
      int needs_slash = ! (dirlen == FILESYSTEM_PREFIX_LEN (dir)
			   || IS_SLASH (dir[dirlen - 1]));
      char *file = NULL;
      char const *namep = name_space;
      struct stats child;
      child.parent = stats;
      out_file += !no_filenames;
      while (*namep)
	{
	  size_t namelen = strlen (namep);
	  file = xrealloc (file, dirlen + 1 + namelen + 1);
	  strcpy (file, dir);
	  file[dirlen] = '/';
	  strcpy (file + dirlen + needs_slash, namep);
	  namep += namelen + 1;
	  status &= grepfile (file, &child);
	}
      out_file -= !no_filenames;
      if (file)
        free (file);
      free (name_space);
    }

  return status;
}

static void
usage (int status)
{
  if (status != 0)
    {
      fprintf (stderr, _("Usage: %s [OPTION]... PATTERN [FILE]...\n"),
	       program_name);
      fprintf (stderr, _("Try `%s --help' for more information.\n"),
	       program_name);
    }
  else
    {
      printf (_("Usage: %s [OPTION]... PATTERN [FILE] ...\n"), program_name);
      printf (_("\
Search for PATTERN in each FILE or standard input.\n\
Example: %s -i 'hello world' menu.h main.c\n\
\n\
Regexp selection and interpretation:\n"), program_name);
      printf (_("\
  -E, --extended-regexp     PATTERN is an extended regular expression\n\
  -F, --fixed-strings       PATTERN is a set of newline-separated strings\n\
  -G, --basic-regexp        PATTERN is a basic regular expression\n\
  -P, --perl-regexp         PATTERN is a Perl regular expression\n"));
      printf (_("\
  -e, --regexp=PATTERN      use PATTERN as a regular expression\n\
  -f, --file=FILE           obtain PATTERN from FILE\n\
  -i, --ignore-case         ignore case distinctions\n\
  -w, --word-regexp         force PATTERN to match only whole words\n\
  -x, --line-regexp         force PATTERN to match only whole lines\n\
  -z, --null-data           a data line ends in 0 byte, not newline\n"));
      printf (_("\
\n\
Miscellaneous:\n\
  -s, --no-messages         suppress error messages\n\
  -v, --invert-match        select non-matching lines\n\
  -V, --version             print version information and exit\n\
      --help                display this help and exit\n\
      --mmap                use memory-mapped input if possible\n"));
      printf (_("\
\n\
Output control:\n\
  -m, --max-count=NUM       stop after NUM matches\n\
  -b, --byte-offset         print the byte offset with output lines\n\
  -n, --line-number         print line number with output lines\n\
      --line-buffered       flush output on every line\n\
  -H, --with-filename       print the filename for each match\n\
  -h, --no-filename         suppress the prefixing filename on output\n\
      --label=LABEL         print LABEL as filename for standard input\n\
  -o, --only-matching       show only the part of a line matching PATTERN\n\
  -q, --quiet, --silent     suppress all normal output\n\
      --binary-files=TYPE   assume that binary files are TYPE\n\
                            TYPE is 'binary', 'text', or 'without-match'\n\
  -a, --text                equivalent to --binary-files=text\n\
  -I                        equivalent to --binary-files=without-match\n\
  -d, --directories=ACTION  how to handle directories\n\
                            ACTION is 'read', 'recurse', or 'skip'\n\
  -D, --devices=ACTION      how to handle devices, FIFOs and sockets\n\
                            ACTION is 'read' or 'skip'\n\
  -R, -r, --recursive       equivalent to --directories=recurse\n\
      --include=PATTERN     files that match PATTERN will be examined\n\
      --exclude=PATTERN     files that match PATTERN will be skipped.\n\
      --exclude-from=FILE   files that match PATTERN in FILE will be skipped.\n\
  -L, --files-without-match only print FILE names containing no match\n\
  -l, --files-with-matches  only print FILE names containing matches\n\
  -c, --count               only print a count of matching lines per FILE\n\
  -Z, --null                print 0 byte after FILE name\n"));
      printf (_("\
\n\
Context control:\n\
  -B, --before-context=NUM  print NUM lines of leading context\n\
  -A, --after-context=NUM   print NUM lines of trailing context\n\
  -C, --context=NUM         print NUM lines of output context\n\
  -NUM                      same as --context=NUM\n\
      --color[=WHEN],\n\
      --colour[=WHEN]       use markers to distinguish the matching string\n\
                            WHEN may be `always', `never' or `auto'.\n\
  -U, --binary              do not strip CR characters at EOL (MSDOS)\n\
  -u, --unix-byte-offsets   report offsets as if CRs were not there (MSDOS)\n\
\n\
`egrep' means `grep -E'.  `fgrep' means `grep -F'.\n\
With no FILE, or when FILE is -, read standard input.  If less than\n\
two FILEs given, assume -h.  Exit status is 0 if match, 1 if no match,\n\
and 2 if trouble.\n"));
      printf (_("\nReport bugs to <[e-mail]>.\n"));
    }
  exit (status);
}

/* Set the matcher to M, reporting any conflicts.  */
static void
setmatcher (char const *m)
{
  if (matcher && strcmp (matcher, m) != 0)
    error (2, 0, _("conflicting matchers specified"));
  matcher = m;
}

/* Go through the matchers vector and look for the specified matcher.
   If we find it, install it in compile and execute, and return 1.  */
static int
install_matcher (char const *name)
{
  int i;
#if defined(HAVE_SETRLIMIT)
  struct rlimit rlim;
#endif

  for (i = 0; matchers[i].compile; i++)
    if (strcmp (name, matchers[i].name) == 0)
      {
	compile = matchers[i].compile;
	execute = matchers[i].execute;
#if defined(HAVE_SETRLIMIT) && defined(RLIMIT_STACK)
	/* I think every platform needs to do this, so that regex.c
	   doesn't oveflow the stack.  The default value of
	   `re_max_failures' is too large for some platforms: it needs
	   more than 3MB-large stack.

	   The test for HAVE_SETRLIMIT should go into `configure'.  */
	if (!getrlimit (RLIMIT_STACK, &rlim))
	  {
	    long newlim;
	    extern long int re_max_failures; /* from regex.c */

	    /* Approximate the amount regex.c needs, plus some more.  */
	    newlim = re_max_failures * 2 * 20 * sizeof (char *);
	    if (newlim > rlim.rlim_max)
	      {
		newlim = rlim.rlim_max;
		re_max_failures = newlim / (2 * 20 * sizeof (char *));
	      }
	    if (rlim.rlim_cur < newlim)
	      {
		rlim.rlim_cur = newlim;
		setrlimit (RLIMIT_STACK, &rlim);
	      }
	  }
#endif
	return 1;
      }
  return 0;
}

/* Find the white-space-separated options specified by OPTIONS, and
   using BUF to store copies of these options, set ARGV[0], ARGV[1],
   etc. to the option copies.  Return the number N of options found.
   Do not set ARGV[N] to NULL.  If ARGV is NULL, do not store ARGV[0]
   etc.  Backslash can be used to escape whitespace (and backslashes).  */
static int
prepend_args (char const *options, char *buf, char **argv)
{
  char const *o = options;
  char *b = buf;
  int n = 0;

  for (;;)
    {
      while (ISSPACE ((unsigned char) *o))
	o++;
      if (!*o)
	return n;
      if (argv)
	argv[n] = b;
      n++;

      do
	if ((*b++ = *o++) == '\\' && *o)
	  b[-1] = *o++;
      while (*o && ! ISSPACE ((unsigned char) *o));

      *b++ = '\0';
    }
}

/* Prepend the whitespace-separated options in OPTIONS to the argument
   vector of a main program with argument count *PARGC and argument
   vector *PARGV.  */
static void
prepend_default_options (char const *options, int *pargc, char ***pargv)
{
  if (options)
    {
      char *buf = xmalloc (strlen (options) + 1);
      int prepended = prepend_args (options, buf, (char **) NULL);
      int argc = *pargc;
      char * const *argv = *pargv;
      char **pp = (char **) xmalloc ((prepended + argc + 1) * sizeof *pp);
      *pargc = prepended + argc;
      *pargv = pp;
      *pp++ = *argv++;
      pp += prepend_args (options, buf, pp);
      while ((*pp++ = *argv++))
	continue;
    }
}

/* Get the next non-digit option from ARGC and ARGV.
   Return -1 if there are no more options.
   Process any digit options that were encountered on the way,
   and store the resulting integer into *DEFAULT_CONTEXT.  */
static int
get_nondigit_option (int argc, char *const *argv, int *default_context)
{
  int opt;
  char buf[sizeof (uintmax_t) * CHAR_BIT + 4];
  char *p = buf;

  /* Set buf[0] to anything but '0', for the leading-zero test below.  */
  buf[0] = '\0';

  while (opt = getopt_long (argc, argv, short_options, long_options, NULL),
	 '0' <= opt && opt <= '9')
    {
      /* Suppress trivial leading zeros, to avoid incorrect
	 diagnostic on strings like 00000000000.  */
      p -= buf[0] == '0';

      *p++ = opt;
      if (p == buf + sizeof buf - 4)
	{
	  /* Too many digits.  Append "..." to make context_length_arg
	     complain about "X...", where X contains the digits seen
	     so far.  */
	  strcpy (p, "...");
	  p += 3;
	  break;
	}
    }
  if (p != buf)
    {
      *p = '\0';
      context_length_arg (buf, default_context);
    }

  return opt;
}

int
main (int argc, char **argv)
{
  char *keys;
  size_t keycc, oldcc, keyalloc;
  int with_filenames;
  int opt, cc, status;
  int default_context;
  FILE *fp;
  extern char *optarg;
  extern int optind;

  initialize_main (&argc, &argv);
  program_name = argv[0];
  if (program_name && strrchr (program_name, '/'))
    program_name = strrchr (program_name, '/') + 1;

  if (!strcmp(program_name, "egrep"))
    setmatcher ("egrep");
  if (!strcmp(program_name, "fgrep"))
    setmatcher ("fgrep");

#if defined(__MSDOS__) || defined(_WIN32)
  /* DOS and MS-Windows use backslashes as directory separators, and usually
     have an .exe suffix.  They also have case-insensitive filesystems.  */
  if (program_name)
    {
      char *p = program_name;
      char *bslash = strrchr (argv[0], '\\');

      if (bslash && bslash >= program_name) /* for mixed forward/backslash case */