Add NK_config struct and read/write functions

This patch adds the NK_config struct to the C API that stores the
general configuration of a Nitrokey device.  It also adds the
NK_read_config_struct and NK_write_config_struct functions to make the
API easier to use.  While NK_write_config_struct is only a convenience
method, NK_read_config_struct makes the API more safe as the user no
longer has to read the data from a pointer to an array.

This patch also extends the test_read_write_config test case with the
two new functions.

1 files changed, 25 insertions, 1 deletions

diff --git a/unittest/test_pro.py b/unittest/test_pro.py
index 99d7b1f..e61d8bf 100644
--- a/unittest/test_pro.py
+++ b/unittest/test_pro.py
@@ -647,6 +647,30 @@ def test_read_write_config(C):
     config = cast_pointer_to_tuple(config_raw_data, 'uint8_t', 5)
     assert config == (0, 1, 2, True, False)
 
+    # use structs: read I
+    config_st = ffi.new('struct NK_config *')
+    if not config_st:
+        raise Exception("Could not allocate config")
+    assert C.NK_read_config_struct(config_st) == DeviceErrorCode.STATUS_OK
+    assert config_st.numlock == 0
+    assert config_st.capslock == 1
+    assert config_st.scrolllock == 2
+    assert config_st.enable_user_password
+    assert not config_st.disable_user_password
+
+    # use structs: write
+    config_st.numlock = 3
+    assert C.NK_write_config_struct(config_st[0], DefaultPasswords.ADMIN_TEMP) == DeviceErrorCode.STATUS_OK
+
+    # use structs: read II
+    err = C.NK_read_config_struct(config_st)
+    assert err == 0
+    assert config_st.numlock == 3
+    assert config_st.capslock == 1
+    assert config_st.scrolllock == 2
+    assert config_st.enable_user_password
+    assert not config_st.disable_user_password
+
     # restore defaults and check
     assert C.NK_first_authenticate(DefaultPasswords.ADMIN, DefaultPasswords.ADMIN_TEMP) == DeviceErrorCode.STATUS_OK
     assert C.NK_write_config(255, 255, 255, False, True, DefaultPasswords.ADMIN_TEMP) == DeviceErrorCode.STATUS_OK
@@ -1038,4 +1062,4 @@ def test_OTP_all_rw(C):
             this_loop_codes.append(('H', i, code))
         all_codes.append(this_loop_codes)
     from pprint import pprint
-    pprint(all_codes)
\ No newline at end of file
+    pprint(all_codes)