ntdll: Allow final null in RtlNormalizeString() even if 0 is an invalid character.

dlls/kernel32/tests/locale.c

@@ -4521,7 +4521,6 @@ static void test_IdnToNameprepUnicode(void)
             int len = ARRAY_SIZE(buf);
             memset( buf, 0xcc, sizeof(buf) );
             status = pRtlNormalizeString( 13, test_data[i].in, test_data[i].in_len, buf, &len );
-            todo_wine_if (!test_data[i].status && (test_data[i].in_len == -1 || !test_data[i].in[test_data[i].in_len - 1]))
             ok( status == test_data[i].status || broken(status == test_data[i].broken_status),
                 "%d: failed %x\n", i, status );
             if (!status) ok( !wcsncmp(test_data[i].out, buf, len), "%d: buf = %s\n", i, wine_dbgstr_wn(buf, len));

dlls/ntdll/locale.c

@@ -437,6 +437,12 @@ static NTSTATUS decompose_string( const struct norm_table *info, const WCHAR *sr
         props = get_char_props( info, ch );
         if (!(decomp = get_decomposition( info, ch, props, buffer, &decomp_len )))
         {
+            /* allow final null */
+            if (!ch && src_pos == src_len - 1 && dst_pos < *dst_len)
+            {
+                dst[dst_pos++] = 0;
+                break;
+            }
             *dst_len = src_pos;
             return STATUS_NO_UNICODE_TRANSLATION;
         }
@@ -1934,6 +1940,8 @@ NTSTATUS WINAPI RtlIsNormalizedString( ULONG form, const WCHAR *str, INT len, BO
                 /* ignore other chars in Hangul range */
                 if (ch >= HANGUL_LBASE && ch < HANGUL_LBASE + 0x100) continue;
                 if (ch >= HANGUL_SBASE && ch < HANGUL_SBASE + 0x2c00) continue;
+                /* allow final null */
+                if (!ch && i == len - 1) continue;
                 return STATUS_NO_UNICODE_TRANSLATION;
             }
         }