glob.c

UNIX下SH的实现源码

#ifdef SHELL
      if (extended_glob)
	flags |= FNM_EXTMATCH;
#endif

      /* Scan the directory, finding all names that match.
	 For each name that matches, allocate a struct globval
	 on the stack and store the name in it.
	 Chain those structs together; lastlink is the front of the chain.  */
      while (1)
	{
#if defined (__DJGPP__)
	  char short_name[13];
#endif
#if defined (SHELL)
	  /* Make globbing interruptible in the shell. */
	  if (interrupt_state)
	    {
	      lose = 1;
	      break;
	    }
#endif /* SHELL */
	  
	  dp = readdir (d);
	  if (dp == NULL)
	    break;

	  /* If this directory entry is not to be used, try again. */
	  if (REAL_DIR_ENTRY (dp) == 0)
	    continue;

	  /* If a leading dot need not be explicitly matched, and the pattern
	     doesn't start with a `.', don't match `.' or `..' */
#define dname dp->d_name
	  if (noglob_dot_filenames == 0 && pat[0] != '.' &&
		(pat[0] != '\\' || pat[1] != '.') &&
		(dname[0] == '.' &&
		  (dname[1] == '\0' || (dname[1] == '.' && dname[2] == '\0'))))
#undef dname
	    continue;

	  /* If a dot must be explicity matched, check to see if they do. */
	  if (noglob_dot_filenames && dp->d_name[0] == '.' && pat[0] != '.' &&
		(pat[0] != '\\' || pat[1] != '.'))
	    continue;

#if defined (__DJGPP__)
         /* Downcase if the short name and long name are equal and
            case is being ignored.  */

         if (glob_ignore_case
             && (strcmp(dp->d_name, _lfn_gen_short_fname (dp->d_name, short_name)) == 0)
/*             && !((use_lfn && strchr(dp->d_name, '.') == NULL) && glob_testdir(dp->d_name) < 0) */
             )
           {
             /* Downcase when the SFN matches the LFN */
             int i;
             char c;
             for (i = 0; dp->d_name[i]; i++)
               {
                 c = dp->d_name[i];
                 dp->d_name[i] = ((c >= 'A' && c <= 'Z') ? c - 'A' + 'a' : c);
               }
           }
#endif
	  if (fnmatch (pat, dp->d_name, flags) != FNM_NOMATCH)
	    {
	      nextlink = (struct globval *) alloca (sizeof (struct globval));
	      nextlink->next = lastlink;
	      nextname = (char *) malloc (D_NAMLEN (dp) + 1);
	      if (nextname == NULL)
		{
		  lose = 1;
		  break;
		}
	      lastlink = nextlink;
	      nextlink->name = nextname;
	      bcopy (dp->d_name, nextname, D_NAMLEN (dp) + 1);
	      ++count;
	    }
	}

      (void) closedir (d);
    }

  if (lose == 0)
    {
      name_vector = (char **) malloc ((count + 1) * sizeof (char *));
      lose |= name_vector == NULL;
    }

  /* Have we run out of memory?	 */
  if (lose)
    {
      /* Here free the strings we have got.  */
      while (lastlink)
	{
	  free (lastlink->name);
	  lastlink = lastlink->next;
	}
#if defined (SHELL)
      if (interrupt_state)
	throw_to_top_level ();
#endif /* SHELL */

      return ((char **)NULL);
    }

  /* Copy the name pointers from the linked list into the vector.  */
  for (i = 0; i < count; ++i)
    {
      name_vector[i] = lastlink->name;
      lastlink = lastlink->next;
    }

  name_vector[count] = NULL;
  return (name_vector);
}

/* Return a new array which is the concatenation of each string in ARRAY
   to DIR.  This function expects you to pass in an allocated ARRAY, and
   it takes care of free()ing that array.  Thus, you might think of this
   function as side-effecting ARRAY. */
static char **
glob_dir_to_array (dir, array)
     char *dir, **array;
{
  register unsigned int i, l;
  int add_slash;
  char **result;

  l = strlen (dir);
  if (l == 0)
    return (array);

#if defined (HAVE_DOS_STYLE_FILE_SYSTEM)
  add_slash = dir[l - 1] != '/' && dir[l - 1] != ':';
#else
  add_slash = dir[l - 1] != '/';
#endif

  i = 0;
  while (array[i] != NULL)
    ++i;

  result = (char **) malloc ((i + 1) * sizeof (char *));
  if (result == NULL)
    return (NULL);

  for (i = 0; array[i] != NULL; i++)
    {
      result[i] = (char *) malloc (l + (add_slash ? 1 : 0)
				   + strlen (array[i]) + 1);
      if (result[i] == NULL)
	return (NULL);
#if 1
      strcpy (result[i], dir);
      if (add_slash)
        result[i][l] = '/';
      strcpy (result[i] + l + add_slash, array[i]);
#else
      (void)sprintf (result[i], "%s%s%s", dir, add_slash ? "/" : "", array[i]);
#endif
    }
  result[i] = NULL;

  /* Free the input array.  */
  for (i = 0; array[i] != NULL; i++)
    free (array[i]);
  free ((char *) array);

  return (result);
}

/* Do globbing on PATHNAME.  Return an array of pathnames that match,
   marking the end of the array with a null-pointer as an element.
   If no pathnames match, then the array is empty (first element is null).
   If there isn't enough memory, then return NULL.
   If a file system error occurs, return -1; `errno' has the error code.  */
char **
glob_filename (pathname)
     char *pathname;
{
  char **result;
  unsigned int result_size;
  char *directory_name, *filename;
  unsigned int directory_len;

  result = (char **) malloc (sizeof (char *));
  result_size = 1;
  if (result == NULL)
    return (NULL);

  result[0] = NULL;

  /* Find the filename.  */
  filename = strrchr (pathname, '/');
#if defined (HAVE_DOS_STYLE_FILE_SYSTEM)
  /* take drive name */
  if (filename == NULL && isalpha (pathname[0]) && pathname[1] == ':')
    filename = pathname + 1;
#endif
  if (filename == NULL)
    {
      filename = pathname;
      directory_name = "";
      directory_len = 0;
    }
  else
    {
      directory_len = (filename - pathname) + 1;
      directory_name = (char *) alloca (directory_len + 1);

      bcopy (pathname, directory_name, directory_len);
      directory_name[directory_len] = '\0';
      ++filename;
    }

  /* If directory_name contains globbing characters, then we
     have to expand the previous levels.  Just recurse. */
  if (glob_pattern_p (directory_name))
    {
      char **directories;
      register unsigned int i;

      if (directory_name[directory_len - 1] == '/')
	directory_name[directory_len - 1] = '\0';

      directories = glob_filename (directory_name);

      if (directories == NULL)
	goto memory_error;
      else if (directories == (char **)&glob_error_return)
	{
	  free ((char *) result);
	  return ((char **) &glob_error_return);
	}
      else if (*directories == NULL)
	{
	  free ((char *) directories);
	  free ((char *) result);
	  return ((char **) &glob_error_return);
	}

      /* We have successfully globbed the preceding directory name.
	 For each name in DIRECTORIES, call glob_vector on it and
	 FILENAME.  Concatenate the results together.  */
      for (i = 0; directories[i] != NULL; ++i)
	{
	  char **temp_results;

	  /* Scan directory even on a NULL pathname.  That way, `*h/'
	     returns only directories ending in `h', instead of all
	     files ending in `h' with a `/' appended. */
	  temp_results = glob_vector (filename, directories[i]);

	  /* Handle error cases. */
	  if (temp_results == NULL)
	    goto memory_error;
	  else if (temp_results == (char **)&glob_error_return)
	    /* This filename is probably not a directory.  Ignore it.  */
	    ;
	  else
	    {
	      char **array;
	      register unsigned int l;

	      array = glob_dir_to_array (directories[i], temp_results);
	      l = 0;
	      while (array[l] != NULL)
		++l;

	      result =
		(char **)realloc (result, (result_size + l) * sizeof (char *));

	      if (result == NULL)
		goto memory_error;

	      for (l = 0; array[l] != NULL; ++l)
		result[result_size++ - 1] = array[l];

	      result[result_size - 1] = NULL;

	      /* Note that the elements of ARRAY are not freed.  */
	      free ((char *) array);
	    }
	}
      /* Free the directories.  */
      for (i = 0; directories[i]; i++)
	free (directories[i]);

      free ((char *) directories);

      return (result);
    }

  /* If there is only a directory name, return it. */
  if (*filename == '\0')
    {
      result = (char **) realloc ((char *) result, 2 * sizeof (char *));
      if (result == NULL)
	return (NULL);
      result[0] = (char *) malloc (directory_len + 1);
      if (result[0] == NULL)
	goto memory_error;
      bcopy (directory_name, result[0], directory_len + 1);
      result[1] = NULL;
      return (result);
    }
  else
    {
      char **temp_results;

      /* There are no unquoted globbing characters in DIRECTORY_NAME.
	 Dequote it before we try to open the directory since there may
	 be quoted globbing characters which should be treated verbatim. */
      if (directory_len > 0)
	dequote_pathname (directory_name);

      /* We allocated a small array called RESULT, which we won't be using.
	 Free that memory now. */
      free (result);

      /* Just return what glob_vector () returns appended to the
	 directory name. */
#if defined(__DJGPP__)
      __opendir_flags = __OPENDIR_PRESERVE_CASE;
#endif
      temp_results =
	glob_vector (filename, (directory_len == 0 ? "." : directory_name));
#if defined (__DJGPP__)
      __opendir_flags = 0;
#endif

      if (temp_results == NULL || temp_results == (char **)&glob_error_return)
	return (temp_results);

      return (glob_dir_to_array (directory_name, temp_results));
    }

  /* We get to memory_error if the program has run out of memory, or
     if this is the shell, and we have been interrupted. */
 memory_error:
  if (result != NULL)
    {
      register unsigned int i;
      for (i = 0; result[i] != NULL; ++i)
	free (result[i]);
      free ((char *) result);
    }
#if defined (SHELL)
  if (interrupt_state)
    throw_to_top_level ();
#endif /* SHELL */
  return (NULL);
}

#if defined (TEST)

main (argc, argv)
     int argc;
     char **argv;
{
  unsigned int i;

  for (i = 1; i < argc; ++i)
    {
      char **value = glob_filename (argv[i]);
      if (value == NULL)
	puts ("Out of memory.");
      else if (value == &glob_error_return)
	perror (argv[i]);
      else
	for (i = 0; value[i] != NULL; i++)
	  puts (value[i]);
    }

  exit (0);
}
#endif	/* TEST.  */