/* savedir.c -- save the list of files in a directory in a string   Copyright 1990, 1997, 1998, 1999, 2000, 2001 Free Software   Foundation, Inc.   This program is free software; you can redistribute it and/or modify   it under the terms of the GNU General Public License as published by   the Free Software Foundation; either version 2, or (at your option)   any later version.   This program is distributed in the hope that it will be useful,   but WITHOUT ANY WARRANTY; without even the implied warranty of   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the   GNU General Public License for more details.   You should have received a copy of the GNU General Public License   along with this program; if not, write to the Free Software Foundation,   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  *//* Written by David MacKenzie <djm@gnu.ai.mit.edu>. */#if HAVE_CONFIG_H# include <config.h>#endif#include <sys/types.h>#include <errno.h>#ifndef errnoextern int errno;#endif#if HAVE_DIRENT_H# include <dirent.h>#else# define dirent direct# if HAVE_SYS_NDIR_H#  include <sys/ndir.h># endif# if HAVE_SYS_DIR_H#  include <sys/dir.h># endif# if HAVE_NDIR_H#  include <ndir.h># endif#endif#ifdef CLOSEDIR_VOID/* Fake a return value. */# define CLOSEDIR(d) (closedir (d), 0)#else# define CLOSEDIR(d) closedir (d)#endif#ifdef STDC_HEADERS# include <stdlib.h># include <string.h>#endif#ifndef NULL# define NULL 0#endif#include "savedir.h"#include "xalloc.h"/* Return a freshly allocated string containing the filenames   in directory DIR, separated by '\0' characters;   the end is marked by two '\0' characters in a row.   Return NULL (setting errno) if DIR cannot be opened, read, or closed.  */#ifndef NAME_SIZE_DEFAULT# define NAME_SIZE_DEFAULT 512#endifchar *savedir (const char *dir){  DIR *dirp;  struct dirent *dp;  char *name_space;  size_t allocated = NAME_SIZE_DEFAULT;  size_t used = 0;  int save_errno;  dirp = opendir (dir);  if (dirp == NULL)    return NULL;  name_space = xmalloc (allocated);  errno = 0;  while ((dp = readdir (dirp)) != NULL)    {      /* Skip "", ".", and "..".  "" is returned by at least one buggy         implementation: Solaris 2.4 readdir on NFS filesystems.  */      char const *entry = dp->d_name;      if (entry[entry[0] != '.' ? 0 : entry[1] != '.' ? 1 : 2] != '\0')	{	  size_t entry_size = strlen (entry) + 1;	  if (used + entry_size < used)	    xalloc_die ();	  if (allocated <= used + entry_size)	    {	      do		{		  if (2 * allocated < allocated)		    xalloc_die ();		  allocated *= 2;		}	      while (allocated <= used + entry_size);	      name_space = xrealloc (name_space, allocated);	    }	  memcpy (name_space + used, entry, entry_size);	  used += entry_size;	}    }  name_space[used] = '\0';  save_errno = errno;  if (CLOSEDIR (dirp) != 0)    save_errno = errno;  if (save_errno != 0)    {      free (name_space);      errno = save_errno;      return NULL;    }  return name_space;}