-uint32_t calc_bitmap_crc(uint32_t *bitmap, unsigned start, unsigned end)
-{
- crc_t crc = 0;
- crc = crc_update(crc, bitmap[0] << start, 32 - start);
- crc = crc_update(crc, bitmap[1], 32);
- crc = crc_update(crc, bitmap[2], end - 64 > 32 ? 32 : end - 64); /* FIXME: This seems to be broken for end < 64 */
- crc = crc_update(crc, bitmap[3], end > 96 ? end - 96 : 0);
- return crc << 17;
-}
-
-unsigned calc_stuff_bits(struct can_frame *frame) {
- uint32_t bitmap[4];
- unsigned start = 0, end;
- uint32_t mask, ones = 0, basemask = 0xf8000000;
- unsigned stuffed = 0;
- memset(bitmap, 0, sizeof(bitmap));
- uint32_t crc;
-
-/* char received[64]; */
-/* sprint_canframe(received, frame, true); */
-/* printf("Frame: %s\n", received); */
-
- if (frame->can_id & CAN_EFF_FLAG) {
- // bit 31 0
- // [0] |...........................sBBBB| s = SOF, B = Base ID (11 bits)
- // [1] |BBBBBBBSIEEEEEEEEEEEEEEEEEER10DLC4| S = SRR, I = IDE, E = Extended ID (18 bits), DLC4 = DLC
- // [2] |00000000111111112222222233333333| Data bytes, MSB first
- // [3] |44444444555555556666666677777777|
- bitmap[0] =
- ((frame->can_id & CAN_EFF_MASK) >> 25);
- bitmap[1] =
- ((frame->can_id & CAN_EFF_MASK) >> 18) << 25 |
- 3 << 23 |
- ((frame->can_id & CAN_EFF_MASK) & 0x3ffff) << 7 |
- (!!(frame->can_id & CAN_RTR_FLAG)) << 6 |
- 0 << 4 |
- frame->can_dlc & 0xf;
- memcpy(&bitmap[2], &frame->data, frame->can_dlc);
- start = 27;
- end = 64 + 8*frame->can_dlc;
- } else {
- // bit 31 0
- // [0] |.............sIIIIIIIIIIIRE0DLC4| s = SOF, I = ID (11 bits), R = RTR, E = IDE, DLC4 = DLC
- // [1] |00000000111111112222222233333333| Data bytes, MSB first
- // [2] |44444444555555556666666677777777|
- bitmap[0] =
- (frame->can_id << 7) |
- (!!(frame->can_id & CAN_RTR_FLAG)) << 6 |
- 0 << 4 |
- frame->can_dlc & 0xf;
- memcpy(&bitmap[1], &frame->data, frame->can_dlc);
- start = 13;
- end = 32 + 8*frame->can_dlc;
- }
- crc = calc_bitmap_crc(bitmap, start, end);
- uint32_t crc_be = htons(crc << 17);
- memcpy((char*)bitmap + end/8, &crc_be, 2); /* end is guaranteed to be divisible by 8 */
- end += 15;
-
- while (start < end) {
- mask = basemask >> (start & 0x1f);
- while (1) {
- ones = ones ? mask : 0;
- uint32_t chunk = (bitmap[start >> 5] & mask) ^ ones;
- //printf("start=%d bitmap=0x%08x mask=0x%08x ones=0x%08x chunk=0x%08x\n", start, bitmap[start >> 5], mask, ones, chunk);
- if (chunk) {
- unsigned change = __builtin_clz(chunk);
- start = start & ~0x1f | change;
- basemask = 0xf8000000;
- } else {
- unsigned oldstart = start;
- start += __builtin_popcount(mask);
- mask = (oldstart & 0x1f) ? basemask << (-oldstart & 0x1f) : 0;
- //printf("oldstart=%d shl=%d mask=0x%08x\n", oldstart, -oldstart & 0x1f, mask);
- if (mask && start < end)
- continue;
- if (start <= end && !mask) {
- stuffed++;
- basemask = 0xf0000000;
- //printf("stuffed %d\n", !ones);
- }
- }
- break;
- }
- ones = !ones;
- }
- //printf ("STUFFED %d BITS\n", stuffed);
- return stuffed;
-}
-
-unsigned calc_frame_txtime_us(struct can_frame *frame) {
- return calc_stuff_bits(frame) +
- 1 + /* SOF */
- 11 + /* ID A */
- ((frame->can_id & CAN_EFF_FLAG) ?
- 1 + /* SRR */
- 1 + /* IDE */
- 18 + /* ID B */
- 1 + /* RTR */
- 2 /* r1, r0 */
- :
- 1 + /* rtr */
- 2) + /* ide, r0 */
- 4 + /* dlc */
- 8*frame->can_dlc +
- 15 + /* CRC */
- 3 + /* CRC del, ACK, ACK del */
- 7; /* EOF */
-}
-
-void msg_info_print(FILE *f, struct msg_info *mi)