common,w32: New function read_w32_reg_string.

* common/w32-reg.c (get_root_key): Remove.
(read_w32_registry_string): Turn into a wrapper for the gpgrt
function.
(read_w32_reg_string): New.

1 files changed, 39 insertions, 161 deletions

diff --git a/common/w32-reg.c b/common/w32-reg.c
index d8d94b90e..94049a283 100644
--- a/common/w32-reg.c
+++ b/common/w32-reg.c
@@ -47,184 +47,62 @@
 #include "w32help.h"
 
 
-static HKEY
-get_root_key(const char *root)
-{
-  HKEY root_key;
-
-  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;
-
-  return root_key;
-}
-
-
 /* 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, HKEY_LOCAL_MACHINE in turn.  */
 char *
 read_w32_registry_string (const char *root, const char *dir, const char *name)
 {
-#ifdef HAVE_W32CE_SYSTEM
-  HKEY root_key, key_handle;
-  DWORD n1, nbytes, type;
-  char *result = NULL;
-  wchar_t *wdir, *wname;
-
-  if ( !(root_key = get_root_key(root) ) )
-    return NULL;
-
-  wdir = utf8_to_wchar (dir);
-  if (!wdir)
-    return NULL;
-
-  if (RegOpenKeyEx (root_key, wdir, 0, KEY_READ, &key_handle) )
-    {
-      if (root)
-        {
-          xfree (wdir);
-          return NULL; /* No need for a RegClose, so return immediately. */
-        }
-      /* It seems to be common practise to fall back to HKLM. */
-      if (RegOpenKeyEx (HKEY_LOCAL_MACHINE, wdir, 0, KEY_READ, &key_handle) )
-        {
-          xfree (wdir);
-          return NULL; /* Still no need for a RegClose. */
-        }
-    }
-  xfree (wdir);
+  return gpgrt_w32_reg_query_string (root, dir, name);
+}
 
-  if (name)
-    {
-      wname = utf8_to_wchar (name);
-      if (!wname)
-        goto leave;
-    }
-  else
-    wname = NULL;
 
-  nbytes = 2;
-  if (RegQueryValueEx (key_handle, wname, 0, NULL, NULL, &nbytes))
-    goto leave;
-  result = xtrymalloc ((n1=nbytes+2));
-  if (!result)
-    goto leave;
-  if (RegQueryValueEx (key_handle, wname, 0, &type, result, &n1))
-    {
-      xfree (result);
-      result = NULL;
-      goto leave;
-    }
-  result[nbytes] = 0;   /* Make sure it is a string.  */
-  result[nbytes+1] = 0;
-  if (type == REG_SZ || type == REG_EXPAND_SZ)
-    {
-      wchar_t *tmp = (void*)result;
-      result = wchar_to_utf8 (tmp);
-      xfree (tmp);
-    }
-
- leave:
-  xfree (wname);
-  RegCloseKey (key_handle);
-  return result;
-#else /*!HAVE_W32CE_SYSTEM*/
-  HKEY root_key, key_handle;
-  DWORD n1, nbytes, type;
-  char *result = NULL;
+/* Compact version of read_w32_registry_string.  This version expects
+ * a single string as key described here using an example:
+ *
+ *    HKCU\Software\GNU\GnuPG:HomeDir
+ *
+ * HKCU := the class, other supported classes are HKLM, HKCR, HKU, and
+ *         HKCC.  If no class is given and the string thus starts with
+ *         a backslash HKCU with a fallback to HKLM is used.
+ * Software\GNU\GnuPG := The actual key.
+ * HomeDir := the name of the item.  The name is optional to use the default
+ *            value.
+ *
+ * Note that the first backslash and the first colon act as delimiters.
+ *
+ * Returns a malloced string or NULL if not found.
+ */
+char *
+read_w32_reg_string (const char *key_arg)
+{
+  char *key;
+  char *p1, *p2;
+  char *result;
 
-  if ( !(root_key = get_root_key(root) ) )
+  if (!key_arg)
     return NULL;
-
-  if (RegOpenKeyEx (root_key, dir, 0, KEY_READ, &key_handle) )
+  key = xtrystrdup (key_arg);
+  if (!key)
     {
-      if (root)
-        return NULL; /* No need for a RegClose, so return immediately. */
-      /* It seems to be common practise to fall back to HKLM. */
-      if (RegOpenKeyEx (HKEY_LOCAL_MACHINE, dir, 0, KEY_READ, &key_handle) )
-        return NULL; /* Still no need for a RegClose. */
+      log_info ("warning: malloc failed while reading registry key\n");
+      return NULL;
     }
 
-  nbytes = 1;
-  if (RegQueryValueEx( key_handle, name, 0, NULL, NULL, &nbytes ) )
-    goto leave;
-  result = xtrymalloc ((n1=nbytes+1));
-  if (!result)
-    goto leave;
-  if (RegQueryValueEx( key_handle, name, 0, &type, result, &n1 ))
+  p1 = strchr (key, '\\');
+  if (!p1)
     {
-      xfree (result);
-      result = NULL;
-      goto leave;
-    }
-  result[nbytes] = 0; /* Make sure it is a string.  */
-  if (type == REG_EXPAND_SZ && strchr (result, '%'))
-    {
-      char *tmp;
-
-      n1 += 1000;
-      tmp = xtrymalloc (n1+1);
-      if (!tmp)
-        goto leave;
-      nbytes = ExpandEnvironmentStrings (result, tmp, n1);
-      if (nbytes && nbytes > n1)
-        {
-          xfree (tmp);
-          n1 = nbytes;
-          tmp = xtrymalloc (n1 + 1);
-          if (!tmp)
-            goto leave;
-          nbytes = ExpandEnvironmentStrings (result, tmp, n1);
-          if (nbytes && nbytes > n1)
-            {
-              /* Oops - truncated, better don't expand at all.  */
-              xfree (tmp);
-              goto leave;
-            }
-          tmp[nbytes] = 0;
-          xfree (result);
-          result = tmp;
-        }
-      else if (nbytes)
-        {
-          /* Okay, reduce the length.  */
-          tmp[nbytes] = 0;
-          xfree (result);
-          result = xtrymalloc (strlen (tmp)+1);
-          if (!result)
-            result = tmp;
-            else
-              {
-                strcpy (result, tmp);
-                xfree (tmp);
-              }
-        }
-      else
-        {
-          /* Error - don't expand.  */
-          xfree (tmp);
-        }
+      xfree (key);
+      return NULL;
     }
+  *p1++ = 0;
+  p2 = strchr (p1, ':');
+  if (p2)
+    *p2++ = 0;
 
- leave:
-  RegCloseKey (key_handle);
+  result = gpgrt_w32_reg_query_string (*key? key : NULL, p1, p2);
+  xfree (key);
   return result;
-#endif /*!HAVE_W32CE_SYSTEM*/
 }
 
-
 #endif /*HAVE_W32_SYSTEM*/