~ruther/qmk_firmware

f3beeb0270ec80d797809e7bb321e4b360a2008d — Fred Sundvik 9 years ago a089eaa
Hanlde sending of zero bytes for small packets
2 files changed, 75 insertions(+), 8 deletions(-)

M serial_link/protocol/byte_stuffer.c
M serial_link/tests/byte_stuffer_tests.c
M serial_link/protocol/byte_stuffer.c => serial_link/protocol/byte_stuffer.c +23 -4
@@ 93,12 93,31 @@ void recv_byte(byte_stuffer_state_t* state, uint8_t data) {
    }
}

static void send_block(uint8_t* start, uint8_t* end, uint8_t num_non_zero) {
    send_data(&num_non_zero, 1);
    if (end > start) {
        send_data(start, end-start);
    }
}

void send_frame(uint8_t* data, uint16_t size) {
    const uint8_t zero = 0;
    if (size > 0) {
        uint8_t numZeroes = size + 1;
        const uint8_t zero = 0;
        send_data(&numZeroes, 1);
        send_data(data, size);
        uint8_t num_non_zero = 1;
        uint8_t* end = data + size;
        uint8_t* start = data;
        while (data < end) {
            if (*data == 0) {
                send_block(start, data, num_non_zero);
                start = data + 1;
                num_non_zero = 1;
            }
            else {
                num_non_zero++;
            }
            ++data;
        }
        send_block(start, data, num_non_zero);
        send_data(&zero, 1);
    }
}

M serial_link/tests/byte_stuffer_tests.c => serial_link/tests/byte_stuffer_tests.c +52 -4
@@ 312,15 312,63 @@ Ensure(ByteStuffer, send_zero_size_frame_does_nothing) {
Ensure(ByteStuffer, send_one_byte_frame) {
    uint8_t data[] = {5};
    send_frame(data, 1);
    assert_that(sent_data_size, is_equal_to(3));
    uint8_t expected[] = {2, 5, 0};
    assert_that(sent_data, is_equal_to_contents_of(expected, 3));
    assert_that(sent_data_size, is_equal_to(sizeof(expected)));
    assert_that(sent_data, is_equal_to_contents_of(expected, sizeof(expected)));
}

Ensure(ByteStuffer, send_two_byte_frame) {
    uint8_t data[] = {5, 0x77};
    send_frame(data, 2);
    assert_that(sent_data_size, is_equal_to(4));
    uint8_t expected[] = {3, 5, 0x77, 0};
    assert_that(sent_data, is_equal_to_contents_of(expected, 4));
    assert_that(sent_data_size, is_equal_to(sizeof(expected)));
    assert_that(sent_data, is_equal_to_contents_of(expected, sizeof(expected)));
}

Ensure(ByteStuffer, send_one_byte_frame_with_zero) {
    uint8_t data[] = {0};
    send_frame(data, 1);
    uint8_t expected[] = {1, 1, 0};
    assert_that(sent_data_size, is_equal_to(sizeof(expected)));
    assert_that(sent_data, is_equal_to_contents_of(expected, sizeof(expected)));
}

Ensure(ByteStuffer, send_two_byte_frame_starting_with_zero) {
    uint8_t data[] = {0, 9};
    send_frame(data, 2);
    uint8_t expected[] = {1, 2, 9, 0};
    assert_that(sent_data_size, is_equal_to(sizeof(expected)));
    assert_that(sent_data, is_equal_to_contents_of(expected, sizeof(expected)));
}

Ensure(ByteStuffer, send_two_byte_frame_starting_with_non_zero) {
    uint8_t data[] = {9, 0};
    send_frame(data, 2);
    uint8_t expected[] = {2, 9, 1, 0};
    assert_that(sent_data_size, is_equal_to(sizeof(expected)));
    assert_that(sent_data, is_equal_to_contents_of(expected, sizeof(expected)));
}

Ensure(ByteStuffer, send_three_byte_frame_zero_in_the_middle) {
    uint8_t data[] = {9, 0, 0x68};
    send_frame(data, 3);
    uint8_t expected[] = {2, 9, 2, 0x68, 0};
    assert_that(sent_data_size, is_equal_to(sizeof(expected)));
    assert_that(sent_data, is_equal_to_contents_of(expected, sizeof(expected)));
}

Ensure(ByteStuffer, send_three_byte_frame_data_in_the_middle) {
    uint8_t data[] = {0, 0x55, 0};
    send_frame(data, 3);
    uint8_t expected[] = {1, 2, 0x55, 1, 0};
    assert_that(sent_data_size, is_equal_to(sizeof(expected)));
    assert_that(sent_data, is_equal_to_contents_of(expected, sizeof(expected)));
}

Ensure(ByteStuffer, send_three_byte_frame_all_zeroes) {
    uint8_t data[] = {0, 0, 0};
    send_frame(data, 3);
    uint8_t expected[] = {1, 1, 1, 1, 0};
    assert_that(sent_data_size, is_equal_to(sizeof(expected)));
    assert_that(sent_data, is_equal_to_contents_of(expected, sizeof(expected)));
}