common/w32reg.c

   1 /* w32reg.c -  MS-Windows Registry access
   2  *      Copyright (C) 1999, 2002 Free Software Foundation, Inc.
   3  *
   4  * This file is part of GnuPG.
   5  *
   6  * GnuPG is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * GnuPG is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  19  */
  20
  21 #include <config.h>
  22 #ifdef HAVE_W32_SYSTEM
  23  /* This module is only used in this environment */
  24
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28 #include <stdarg.h>
  29 #include <windows.h>
  30
  31 #include "util.h"
  32 #include "sysutils.h"
  33
  34 static HKEY
  35 get_root_key(const char *root)
  36 {
  37     HKEY root_key;
  38
  39     if( !root )
  40         root_key = HKEY_CURRENT_USER;
  41     else if( !strcmp( root, "HKEY_CLASSES_ROOT" ) )
  42         root_key = HKEY_CLASSES_ROOT;
  43     else if( !strcmp( root, "HKEY_CURRENT_USER" ) )
  44         root_key = HKEY_CURRENT_USER;
  45     else if( !strcmp( root, "HKEY_LOCAL_MACHINE" ) )
  46         root_key = HKEY_LOCAL_MACHINE;
  47     else if( !strcmp( root, "HKEY_USERS" ) )
  48         root_key = HKEY_USERS;
  49     else if( !strcmp( root, "HKEY_PERFORMANCE_DATA" ) )
  50         root_key = HKEY_PERFORMANCE_DATA;
  51     else if( !strcmp( root, "HKEY_CURRENT_CONFIG" ) )
  52         root_key = HKEY_CURRENT_CONFIG;
  53     else
  54         return NULL;
  55
  56     return root_key;
  57 }
  58
  59
  60 /****************
  61  * Return a string from the Win32 Registry or NULL in case of
  62  * error.  Caller must release the return value.   A NULL for root
  63  * is an alias for HKEY_CURRENT_USER, HKEY_LOCAL_MACHINE in turn.
  64  * NOTE: The value is allocated with a plain malloc() - use free() and not
  65  * the usual m_free()!!!
  66  */
  67 char *
  68 read_w32_registry_string( const char *root, const char *dir, const char *name )
  69 {
  70     HKEY root_key, key_handle;
  71     DWORD n1, nbytes, type;
  72     char *result = NULL;
  73
  74     if ( !(root_key = get_root_key(root) ) )
  75         return NULL;
  76
  77     if( RegOpenKeyEx( root_key, dir, 0, KEY_READ, &key_handle ) )
  78       {
  79         if (root)
  80           return NULL; /* no need for a RegClose, so return direct */
  81         /* It seems to be common practise to fall back to HLM. */
  82         if (RegOpenKeyEx (HKEY_LOCAL_MACHINE, dir, 0, KEY_READ, &key_handle) )
  83           return NULL; /* still no need for a RegClose, so return direct */
  84       }
  85
  86     nbytes = 1;
  87     if( RegQueryValueEx( key_handle, name, 0, NULL, NULL, &nbytes ) )
  88         goto leave;
  89     result = malloc( (n1=nbytes+1) );
  90     if( !result )
  91         goto leave;
  92     if( RegQueryValueEx( key_handle, name, 0, &type, result, &n1 ) ) {
  93         free(result); result = NULL;
  94         goto leave;
  95     }
  96     result[nbytes] = 0; /* make sure it is really a string  */
  97     if (type == REG_EXPAND_SZ && strchr (result, '%')) {
  98         char *tmp;
  99
 100         n1 += 1000;
 101         tmp = malloc (n1+1);
 102         if (!tmp)
 103             goto leave;
 104         nbytes = ExpandEnvironmentStrings (result, tmp, n1);
 105         if (nbytes && nbytes > n1) {
 106             free (tmp);
 107             n1 = nbytes;
 108             tmp = malloc (n1 + 1);
 109             if (!tmp)
 110                 goto leave;
 111             nbytes = ExpandEnvironmentStrings (result, tmp, n1);
 112             if (nbytes && nbytes > n1) {
 113                 free (tmp); /* oops - truncated, better don't expand at all */
 114                 goto leave;
 115             }
 116             tmp[nbytes] = 0;
 117             free (result);
 118             result = tmp;
 119         }
 120         else if (nbytes) { /* okay, reduce the length */
 121             tmp[nbytes] = 0;
 122             free (result);
 123             result = malloc (strlen (tmp)+1);
 124             if (!result)
 125                 result = tmp;
 126             else {
 127                 strcpy (result, tmp);
 128                 free (tmp);
 129             }
 130         }
 131         else {  /* error - don't expand */
 132             free (tmp);
 133         }
 134     }
 135
 136   leave:
 137     RegCloseKey( key_handle );
 138     return result;
 139 }
 140
 141
 142 int
 143 write_w32_registry_string(const char *root, const char *dir,
 144                           const char *name, const char *value)
 145 {
 146     HKEY root_key, reg_key;
 147
 148     if ( !(root_key = get_root_key(root) ) )
 149         return -1;
 150
 151     if ( RegOpenKeyEx( root_key, dir, 0, KEY_WRITE, &reg_key )
 152          != ERROR_SUCCESS )
 153         return -1;
 154
 155     if ( RegSetValueEx( reg_key, name, 0, REG_SZ, (BYTE *)value,
 156                         strlen( value ) ) != ERROR_SUCCESS ) {
 157         if ( RegCreateKey( root_key, name, &reg_key ) != ERROR_SUCCESS ) {
 158             RegCloseKey(reg_key);
 159             return -1;
 160         }
 161         if ( RegSetValueEx( reg_key, name, 0, REG_SZ, (BYTE *)value,
 162                             strlen( value ) ) != ERROR_SUCCESS ) {
 163             RegCloseKey(reg_key);
 164             return -1;
 165         }
 166     }
 167
 168     RegCloseKey( reg_key );
 169
 170     return 0;
 171 }
 172
 173 #endif /*HAVE_W32_SYSTEM*/