advapi32: Do not fail in RegQueryInfoKey if *class_len is 0.

dlls/advapi32/registry.c

@@ -849,7 +849,7 @@ LSTATUS WINAPI RegQueryInfoKeyW( HKEY hkey, LPWSTR class, LPDWORD class_len, LPD
     status = NtQueryKey( hkey, KeyFullInformation, buffer, sizeof(buffer), &total_size );
     if (status && status != STATUS_BUFFER_OVERFLOW) goto done;
 
-    if (class)
+    if (class && class_len && *class_len)
     {
         /* retry with a dynamically allocated buffer */
         while (status == STATUS_BUFFER_OVERFLOW)
@@ -1052,7 +1052,8 @@ LSTATUS WINAPI RegQueryInfoKeyA( HKEY hkey, LPSTR class, LPDWORD class_len, LPDW
         RtlUnicodeToMultiByteSize( &len, (WCHAR *)(buf_ptr + info->ClassOffset), info->ClassLength);
         if (class_len)
         {
-            if (len + 1 > *class_len) status = STATUS_BUFFER_OVERFLOW;
+            if (*class_len == 0) class = NULL;
+            if (class && len + 1 > *class_len) status = STATUS_BUFFER_OVERFLOW;
             *class_len = len;
         }
         if (class && !status)

dlls/advapi32/tests/registry.c

@@ -1747,7 +1747,7 @@ static void test_reg_query_info(void)
 
     /* with subkey & default value */
     ret = RegQueryInfoKeyA(subkey, NULL, &classlen, NULL, &subkeys, &maxsubkeylen, &maxclasslen, &values, &maxvaluenamelen, &maxvaluelen, &sdlen, &lastwrite);
-    todo_wine ok(ret == ERROR_SUCCESS, "ret = %d\n", ret);
+    ok(ret == ERROR_SUCCESS, "ret = %d\n", ret);
     ok(classlen == strlen(subkey_class), "classlen = %u\n", classlen);
     ok(subkeys == 1, "subkeys = %u\n", subkeys);
     ok(maxsubkeylen == strlen("subsubkey"), "maxsubkeylen = %u\n", maxsubkeylen);
@@ -1780,7 +1780,7 @@ static void test_reg_query_info(void)
 
     /* with named value */
     ret = RegQueryInfoKeyA(subkey, NULL, &classlen, NULL, &subkeys, &maxsubkeylen, &maxclasslen, &values, &maxvaluenamelen, &maxvaluelen, &sdlen, &lastwrite);
-    todo_wine ok(ret == ERROR_SUCCESS, "ret = %d\n", ret);
+    ok(ret == ERROR_SUCCESS, "ret = %d\n", ret);
     ok(values == 3, "values = %u\n", values);
     ok(maxvaluenamelen == strlen("value one"), "maxvaluenamelen = %u\n", maxvaluenamelen);
     ok(maxvaluelen == sizeof("second value data") * sizeof(WCHAR), "maxvaluelen = %u\n", maxvaluelen);
@@ -1795,7 +1795,7 @@ static void test_reg_query_info(void)
     memset(classbuffer, 0x55, sizeof(classbuffer));
     classlen = 0;
     ret = RegQueryInfoKeyA(subkey, classbuffer, &classlen, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL);
-    todo_wine ok(ret == ERROR_SUCCESS, "ret = %d\n", ret);
+    ok(ret == ERROR_SUCCESS, "ret = %d\n", ret);
     ok(classlen == strlen(subkey_class) /* win2k */ ||
        classlen == 0, "classlen = %u\n", classlen);
     memset(expectbuffer, 0x55, sizeof(expectbuffer));
@@ -1804,7 +1804,7 @@ static void test_reg_query_info(void)
     memset(classbufferW, 0x55, sizeof(classbufferW));
     classlen = 0;
     ret = RegQueryInfoKeyW(subkey, classbufferW, &classlen, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL);
-    todo_wine ok(ret == ERROR_SUCCESS, "ret = %d\n", ret);
+    ok(ret == ERROR_SUCCESS, "ret = %d\n", ret);
     ok(classlen == strlen(subkey_class) /* win2k */ ||
        classlen == 0, "classlen = %u\n", classlen);
     memset(expectbufferW, 0x55, sizeof(expectbufferW));