+int out_sendmmsg(struct out_ctx *ctx, struct can_frame *cf)
+{
+ if (ctx->from_in == NOP)
+ return 0;
+
+ memcpy(ctx->bufs[ctx->current++], cf, sizeof(*cf));
+
+ if (ctx->from_in == SEND ||
+ ctx->current >= MMSG_MAX) {
+ int ret, i;
+ for (i = 0; i < ctx->current; i += ret)
+ ret = CHECK(sendmmsg(ctx->s, &ctx->msgs[i], ctx->current - i, 0));
+ ctx->current = 0;
+ }
+ return 0;
+}
+
+void init_sendmmsg(struct out_ctx *ctx)
+{
+ int i;
+
+ init_write(ctx);
+ ctx->out_fn = out_sendmmsg;
+ ctx->current = 0;
+ ctx->stored = 0;
+
+ memset(ctx->msgs, 0, sizeof(ctx->msgs));
+ memset(ctx->iovecs, 0, sizeof(ctx->iovecs));
+ for (i = 0; i < MMSG_MAX; i++) {
+ ctx->iovecs[i].iov_base = &ctx->bufs[i];
+ ctx->iovecs[i].iov_len = sizeof(struct can_frame);
+ ctx->msgs[i].msg_hdr.msg_iov = &ctx->iovecs[i];
+ ctx->msgs[i].msg_hdr.msg_iovlen = 1;
+ }
+}
+
+int out_packet_tx(struct out_ctx *ctx, struct can_frame *cf)
+{
+ volatile struct tpacket2_hdr *hdr = ctx->ptr + ctx->current*FRAME_SIZE;
+
+ if (ctx->from_in == NOP) {
+ CHECK(send(ctx->s, NULL, 0, 0));
+ return 0;
+ }
+
+ while (hdr->tp_status != TP_STATUS_AVAILABLE) {
+ CHECK(send(ctx->s, NULL, 0, 0));
+ }
+
+ //struct sockaddr_ll *addr = (void*)hdr + TPACKET_HDRLEN - sizeof(struct sockaddr_ll);
+ struct can_frame *cf_mmap = (void*)hdr + TPACKET_HDRLEN - sizeof(struct sockaddr_ll);
+ *cf_mmap = *cf;
+ hdr->tp_len = sizeof(*cf);
+ hdr->tp_status = TP_STATUS_SEND_REQUEST;
+ ctx->current = (ctx->current + 1) % FRAME_NR;
+
+ if (ctx->from_in == SEND){
+ CHECK(send(ctx->s, NULL, 0, 0));
+ return 0;
+ }
+ return 0;
+}
+
+
+void init_packet_tx(struct out_ctx *ctx)
+{
+ int s;
+ struct sockaddr_ll my_addr;
+ struct ifreq ifr;
+
+ s = CHECK(socket(PF_PACKET, SOCK_RAW, htons(ETH_P_ALL)));
+
+ int val = TPACKET_V2;
+ CHECK(setsockopt(s, SOL_PACKET, PACKET_VERSION, &val, sizeof(val)));
+ socklen_t len = sizeof(ctx->hdrlen);
+ CHECK(getsockopt(s, SOL_PACKET, PACKET_HDRLEN, &ctx->hdrlen, &len));
+
+ strncpy (ifr.ifr_name, devout, sizeof(ifr.ifr_name));
+ CHECK(ioctl(s, SIOCGIFINDEX, &ifr));
+
+ my_addr.sll_family = AF_PACKET;
+ my_addr.sll_protocol = htons(ETH_P_CAN);
+ my_addr.sll_ifindex = ifr.ifr_ifindex;
+
+ CHECK(bind(s, (struct sockaddr *)&my_addr, sizeof(struct sockaddr_ll)));
+
+ struct tpacket_req req = {
+ .tp_block_size = BLOCK_SIZE,
+ .tp_frame_size = FRAME_SIZE,
+ .tp_block_nr = BLOCK_NR,
+ .tp_frame_nr = FRAME_NR,
+ };
+ CHECK(setsockopt(s, SOL_PACKET, PACKET_TX_RING, (char *)&req, sizeof(req)));
+
+ ctx->ptr = (char*)CHECKPTR(mmap(0, BLOCK_SIZE*BLOCK_NR, PROT_READ|PROT_WRITE, MAP_SHARED, s, 0));
+
+ ctx->s = s;
+ ctx->out_fn = out_packet_tx;
+ ctx->current = 0;
+}
+