/* w32-util.c - Utility functions for the W32 API
 *      Copyright (C) 1999 Free Software Foundation, Inc
 *	Copyright (C) 2001 Werner Koch (dd9jn)
 *      Copyright (C) 2001, 2002 g10 Code GmbH
 *
 * This file is part of GPGME.
 *
 * GPGME 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 of the License, or
 * (at your option) any later version.
 *
 * GPGME 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
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <errno.h>
#include <sys/time.h>
#include <sys/types.h>
#include <signal.h>
#include <fcntl.h>
#include <windows.h>
#include <io.h>

#include "util.h"
#include "sema.h"

DEFINE_STATIC_LOCK (get_path_lock);

/* Return a string from the Win32 Registry or NULL in case of error.
  Caller must release the return value.  A NULL for root is an alias
  for HKEY_CURRENT_USER.  */
static char *
read_w32_registry_string (const char *root, const char *dir, const char *name)
{
  HKEY root_key, key_handle;
  DWORD n1, nbytes;
  char *result = NULL;

  if (!root)
    root_key = HKEY_CURRENT_USER;
  else if (!strcmp (root, "HKEY_CLASSES_ROOT"))
    root_key = HKEY_CLASSES_ROOT;
  else if (!strcmp (root, "HKEY_CURRENT_USER"))
    root_key = HKEY_CURRENT_USER;
  else if (!strcmp (root, "HKEY_LOCAL_MACHINE"))
    root_key = HKEY_LOCAL_MACHINE;
  else if (!strcmp (root, "HKEY_USERS"))
    root_key = HKEY_USERS;
  else if (!strcmp (root, "HKEY_PERFORMANCE_DATA"))
    root_key = HKEY_PERFORMANCE_DATA;
  else if (!strcmp (root, "HKEY_CURRENT_CONFIG"))
    root_key = HKEY_CURRENT_CONFIG;
  else
    return NULL;

  if (RegOpenKeyEx (root_key, dir, 0, KEY_READ, &key_handle))
    return NULL;	/* No need for a RegClose, so return directly.  */

  nbytes = 1;
  if (RegQueryValueEx (key_handle, name, 0, NULL, NULL, &nbytes))
    goto leave;
  n1 = nbytes + 1;
  result = malloc (n1);
  if (!result)
    goto leave;
  if (RegQueryValueEx (key_handle, name, 0, NULL, result, &n1))
    {
      free (result);
      result = NULL;
      goto leave;
    }
  result[nbytes] = 0;	/* Make sure it is really a string.  */

 leave:
  RegCloseKey (key_handle);
  return result;
}


static const char *
find_program_in_registry (const char *name)
{
  char *program = NULL;
    
  program = read_w32_registry_string (NULL, "Software\\GNU\\GnuPG", name);
  if (program)
    {
      int i;

      DEBUG2 ("found %s in registry: `%s'", name, program);
      for (i = 0; program[i]; i++)
	{
	  if (program[i] == '/')
	    program[i] = '\\';
	}
    }
  return program;
}


const char *
_gpgme_get_gpg_path (void)
{
  static char *gpg_program;

  LOCK (get_path_lock);
  if (!gpg_program)
    gpg_program = find_program_in_registry ("gpgProgram");
#ifdef GPG_PATH
  if (!gpg_program)
    gpg_program = GPG_PATH;
#endif
  UNLOCK (get_path_lock);
  return gpg_program;
}

const char *
_gpgme_get_gpgsm_path (void)
{
  static char *gpgsm_program;

  LOCK (get_path_lock);
  if (!gpgsm_program)
    gpgsm_program = find_program_in_registry ("gpgsmProgram");
#ifdef GPGSM_PATH
  if (!gpgsm_program)
    gpgsm_program = GPGSM_PATH;
#endif
  UNLOCK (get_path_lock);
  return gpgsm_program;
}