/* keybox-util.c - Utility functions for Keybox

 *  Copyright (C) 2001 Free Software Foundation, Inc.

 *

 * This file is part of GnuPG.

 *

 * GnuPG 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 3 of the License, or

 * (at your option) any later version.

 *

 * GnuPG 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, see <https://www.gnu.org/licenses/>.

 */

#include <config.h>

#include <stdlib.h>

#include <stdio.h>

#include <string.h>

#ifdef  HAVE_DOSISH_SYSTEM

# define WIN32_LEAN_AND_MEAN  /* We only need the OS core stuff.  */

# include <windows.h>

#endif

#include "keybox-defs.h"

/* Store the two malloced temporary file names used for keybox updates

   of file FILENAME at R_BAKNAME and R_TMPNAME.  On error an error

   code is returned and NULL stored at R_BAKNAME and R_TMPNAME.  If

   FOR_KEYRING is true the returned names match those used by GnuPG's

   keyring code.  */

gpg_error_t

keybox_tmp_names (const char *filename, int for_keyring,

                  char **r_bakname, char **r_tmpname)

{

  gpg_error_t err;

  char *bak_name, *tmp_name;

  *r_bakname = NULL;

  *r_tmpname = NULL;

# ifdef USE_ONLY_8DOT3

  /* Here is another Windoze bug?:

   * you can't rename("pubring.kbx.tmp", "pubring.kbx");

   * but  rename("pubring.kbx.tmp", "pubring.aaa");

   * works.  So we replace ".kbx" by ".kb_" or ".k__".  Note that we

   * can't use ".bak" and ".tmp", because these suffixes are used by

   * gpg's keyrings and would lead to a sharing violation or data

   * corruption.  If the name does not end in ".kbx" we assume working

   * on a modern file system and append the suffix.  */

  {

    const char *ext   = for_keyring? EXTSEP_S GPGEXT_GPG : EXTSEP_S "kbx";

    const char *b_ext = for_keyring? EXTSEP_S "bak"      : EXTSEP_S "kb_";

    const char *t_ext = for_keyring? EXTSEP_S "tmp"      : EXTSEP_S "k__";

    int repl;

    if (strlen (ext) != 4 || strlen (b_ext) != 4)

      BUG ();

    repl = (strlen (filename) > 4

            && !strcmp (filename + strlen (filename) - 4, ext));

    bak_name = xtrymalloc (strlen (filename) + (repl?0:4) + 1);

    if (!bak_name)

      return gpg_error_from_syserror ();

    strcpy (bak_name, filename);

    strcpy (bak_name + strlen (filename) - (repl?4:0), b_ext);

    tmp_name = xtrymalloc (strlen (filename) + (repl?0:4) + 1);

    if (!tmp_name)

      {

        err = gpg_error_from_syserror ();

        xfree (bak_name);

        return err;

      }

    strcpy (tmp_name, filename);

    strcpy (tmp_name + strlen (filename) - (repl?4:0), t_ext);

  }

# else /* Posix file names */

  (void)for_keyring;

  bak_name = xtrymalloc (strlen (filename) + 2);

  if (!bak_name)

    return gpg_error_from_syserror ();

  strcpy (stpcpy (bak_name, filename), "~");

  tmp_name = xtrymalloc (strlen (filename) + 5);

  if (!tmp_name)

    {

      err = gpg_error_from_syserror ();

      xfree (bak_name);

      return err;

    }

  strcpy (stpcpy (tmp_name,filename), EXTSEP_S "tmp");

# endif /* Posix filename */

  *r_bakname = bak_name;

  *r_tmpname = tmp_name;

  return 0;

}