struct mmsghdr msgs[MMSG_MAX];
struct iovec iovecs[MMSG_MAX];
-char bufs[MMSG_MAX][sizeof(struct can_frame)];
+struct can_frame cf[MMSG_MAX];
-int init_recvmmsg_socket(const char *dev)
+int init_recvmmsg(const char *dev)
{
int sock;
struct sockaddr_can addr;
memset(msgs, 0, sizeof(msgs));
memset(iovecs, 0, sizeof(iovecs));
for (i = 0; i < MMSG_MAX; i++) {
- iovecs[i].iov_base = bufs[i];
- iovecs[i].iov_len = sizeof(struct can_frame);
+ iovecs[i].iov_base = &cf[i];
+ iovecs[i].iov_len = sizeof(cf[i]);
msgs[i].msg_hdr.msg_iov = &iovecs[i];
msgs[i].msg_hdr.msg_iovlen = 1;
}
printf("Received %d CAN frames in one system call\n", received);
for (i = 0; i < received; i++)
- print_can_frame((struct can_frame*)bufs[i]);
+ print_can_frame(&cf[i]);
}
int main(int argc, char *argv[])
dev = candump_parse_args(argc, argv);
- sock = init_recvmmsg_socket(dev);
+ sock = init_recvmmsg(dev);
while (1)
can_recvmmsg(sock);
--- /dev/null
+/**************************************************************/
+/* CAN system calls example */
+/* Author: Michal Sojka, Czech Technical University in Prague */
+/* License: Public domain */
+/**************************************************************/
+
+#include "common.h"
+
+#include <linux/can.h>
+#include <net/if.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <stdbool.h>
+#include <string.h>
+#include <sys/socket.h>
+#include <linux/if_packet.h>
+#include <net/ethernet.h> /* the L2 protocols */
+#include <sys/ioctl.h>
+#include <arpa/inet.h>
+#include <sys/mman.h>
+#include <poll.h>
+
+#define FRAME_SIZE 128
+#define BLOCK_SIZE 4096
+#define BLOCK_NR 2
+#define FRAME_NR (BLOCK_NR*(BLOCK_SIZE/FRAME_SIZE))
+
+void *tx_ring_buffer;
+
+int init_mmap_socket(const char *dev)
+{
+ int sock;
+ struct sockaddr_ll addr;
+ struct ifreq ifr;
+
+ sock = CHECK(socket(PF_PACKET, SOCK_RAW, htons(ETH_P_ALL)));
+
+ int val = TPACKET_V2;
+ CHECK(setsockopt(sock, SOL_PACKET, PACKET_VERSION, &val, sizeof(val)));
+
+ strncpy (ifr.ifr_name, dev, sizeof(ifr.ifr_name));
+ CHECK(ioctl(sock, SIOCGIFINDEX, &ifr));
+
+ addr.sll_family = AF_PACKET;
+ addr.sll_protocol = htons(ETH_P_CAN);
+ addr.sll_ifindex = ifr.ifr_ifindex;
+
+ CHECK(bind(sock, (struct sockaddr *)&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(sock, SOL_PACKET, PACKET_TX_RING, (char *)&req, sizeof(req)));
+
+ tx_ring_buffer = (void*)CHECKPTR(mmap(0, BLOCK_SIZE*BLOCK_NR, PROT_READ|PROT_WRITE, MAP_SHARED, sock, 0));
+
+ return sock;
+}
+
+void can_tx_mmap(int sock, const struct can_frame *cf, int count)
+{
+ int i;
+ for (i = 0; i < count; i++) {
+ volatile struct tpacket2_hdr *hdr = tx_ring_buffer + i * FRAME_SIZE;
+
+ struct can_frame *cf_mmap = (void*)hdr + TPACKET_HDRLEN - sizeof(struct sockaddr_ll);
+ *cf_mmap = cf[i];
+ hdr->tp_len = sizeof(cf[i]);
+ hdr->tp_status = TP_STATUS_SEND_REQUEST;
+ }
+
+ CHECK(send(sock, NULL, 0, 0));
+}
+
+int main(int argc, char *argv[])
+{
+ const char *dev;
+ int sock, count;
+ struct can_frame cf[FRAME_NR];
+
+ dev = cansend_parse_args(argc, argv, &count, cf, FRAME_NR);
+
+ sock = init_mmap_socket(dev);
+
+ can_tx_mmap(sock, cf, count);
+ sleep(1);
+ return 0;
+}
--- /dev/null
+/**************************************************************/
+/* CAN system calls example */
+/* Author: Michal Sojka, Czech Technical University in Prague */
+/* License: Public domain */
+/**************************************************************/
+
+#define _GNU_SOURCE
+
+#include "common.h"
+
+#include <linux/can.h>
+#include <net/if.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <stdbool.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <sys/socket.h>
+
+#define MMSG_MAX 64
+
+struct mmsghdr msgs[MMSG_MAX];
+struct iovec iovecs[MMSG_MAX];
+struct can_frame cf[MMSG_MAX];
+
+int init_sendmmsg(const char *dev)
+{
+ int sock, i;
+ struct sockaddr_can addr;
+ struct ifreq ifr;
+
+ sock = CHECK(socket(PF_CAN, SOCK_RAW, CAN_RAW));
+
+ strncpy(ifr.ifr_name, dev, sizeof(ifr.ifr_name));
+ if (-1 == ioctl(sock, SIOCGIFINDEX, &ifr)) {
+ perror(dev);
+ exit(1);
+ }
+
+ addr.can_family = AF_CAN;
+ addr.can_ifindex = ifr.ifr_ifindex;
+
+ CHECK(bind(sock, (struct sockaddr *)&addr, sizeof(addr)));
+
+ memset(msgs, 0, sizeof(msgs));
+ memset(iovecs, 0, sizeof(iovecs));
+ for (i = 0; i < MMSG_MAX; i++) {
+ iovecs[i].iov_base = &cf[i];
+ iovecs[i].iov_len = sizeof(cf[i]);
+ msgs[i].msg_hdr.msg_iov = &iovecs[i];
+ msgs[i].msg_hdr.msg_iovlen = 1;
+ }
+
+ return sock;
+}
+
+void can_sendmmsg(int sock, int count)
+{
+ CHECK(sendmmsg(sock, msgs, count, 0));
+}
+
+int main(int argc, char *argv[])
+{
+ const char *dev;
+ int sock, count;
+
+ dev = cansend_parse_args(argc, argv, &count, cf, MMSG_MAX);
+
+ sock = init_sendmmsg(dev);
+
+ can_sendmmsg(sock, count);
+
+ return 0;
+}
--- /dev/null
+/**************************************************************/
+/* CAN system calls example */
+/* Author: Michal Sojka, Czech Technical University in Prague */
+/* License: Public domain */
+/**************************************************************/
+
+#include "common.h"
+
+#include <linux/can.h>
+#include <net/if.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <stdbool.h>
+#include <string.h>
+#include <sys/ioctl.h>
+
+int init_write_socket(const char *dev)
+{
+ int sock;
+ struct sockaddr_can addr;
+ struct ifreq ifr;
+
+ sock = CHECK(socket(PF_CAN, SOCK_RAW, CAN_RAW));
+
+ strncpy(ifr.ifr_name, dev, sizeof(ifr.ifr_name));
+ if (-1 == ioctl(sock, SIOCGIFINDEX, &ifr)) {
+ perror(dev);
+ exit(1);
+ }
+
+ addr.can_family = AF_CAN;
+ addr.can_ifindex = ifr.ifr_ifindex;
+
+ CHECK(bind(sock, (struct sockaddr *)&addr, sizeof(addr)));
+
+ return sock;
+}
+
+void can_write(int sock, struct can_frame *cf)
+{
+ int ret = write(sock, cf, sizeof(*cf));
+
+ if (ret != sizeof(*cf)) {
+ perror("write");
+ exit(1);
+ }
+}
+
+int main(int argc, char *argv[])
+{
+ const char *dev;
+ int sock, i, count;
+ struct can_frame cf[100];
+
+ dev = cansend_parse_args(argc, argv, &count, cf, 100);
+
+ sock = init_write_socket(dev);
+
+ for (i = 0; i < count; i++)
+ can_write(sock, &cf[i]);
+
+ return 0;
+}
#include <stdio.h>
#include <stdlib.h>
+#define MIN(a, b) ((a) < (b) ? (a) : (b))
+
#define STRINGIFY(val) #val
#define TOSTRING(val) STRINGIFY(val)
printf("\n");
}
+void can_str2frame(const char *str, struct can_frame *cf)
+{
+ char *extra;
+ unsigned char *d = cf->data;
+ int ret = sscanf(str,
+ "%x#%2hhx%2hhx%2hhx%2hhx%2hhx%2hhx%2hhx%2hhx%ms",
+ &cf->can_id,
+ d+0, d+1, d+2, d+3, d+4, d+5, d+6, d+7, &extra);
+ if (ret < 1) {
+ fprintf(stderr, "Error parsing CAN frame '%s'\n", str);
+ exit(1);
+ }
+ if (ret > 9) {
+ fprintf(stderr, "Error: Extra input '%s'\n", extra);
+ exit(1);
+ }
+ cf->can_dlc = ret - 1;
+}
+
+char *cansend_parse_args(int argc, char *argv[], int *count, struct can_frame *cf_array, size_t max_count)
+{
+ int i;
+ if (argc < 3) {
+ fprintf(stderr, "Usage: %s <CAN interface> <CAN frame>...\n", argv[0]);
+ fprintf(stderr, " CAN frame is ID#DATA, e.g. 123#4567\n");
+ exit(1);
+ }
+
+ for (i = 0; i < MIN(argc - 2, max_count); i++)
+ can_str2frame(argv[i + 2], &cf_array[i]);
+ *count = argc - 2;
+ return argv[1];
+}
#endif
projects / sojka / can-syscalls-examples.git / commitdiff