options to report down/up on can devices, (and not exit when down)

pull/29/head
ajneu 2016-08-30 23:29:13 +02:00
parent 8f74b1cc21
commit 2ca7d6fd2e
1 changed files with 116 additions and 8 deletions

124
candump.c
View File

@ -61,6 +61,7 @@
#include <linux/can.h>
#include <linux/can/raw.h>
#include <linux/rtnetlink.h>
#include "terminal.h"
#include "lib.h"
@ -120,6 +121,8 @@ void print_usage(char *prg)
fprintf(stderr, " -L (use log file format on stdout)\n");
fprintf(stderr, " -n <count> (terminate after receiption of <count> CAN frames)\n");
fprintf(stderr, " -r <size> (set socket receive buffer to <size>)\n");
fprintf(stderr, " -R (Report down-and-up-again status for \"detected\" devices.\n");
fprintf(stderr, " For any device that is only matched via \"any\": Such a device is only \"detected\", once you have received at least one frame from that device.\n");
fprintf(stderr, " -D (Don't exit if a \"detected\" can device goes down.\n");
fprintf(stderr, " -d (monitor dropped CAN frames)\n");
fprintf(stderr, " -e (dump CAN error frames in human-readable format)\n");
@ -152,6 +155,19 @@ void sigterm(int signo)
running = 0;
}
// idx of "detected" devices is cached
int is_idx_cached(int ifidx) {
int cached = 0;
int i;
for (i=0; i < MAXIFNAMES; i++) {
if (dindex[i] == ifidx) {
cached = 1;
break;
}
}
return cached;
}
int idx2dindex(int ifidx, int socket) {
int i;
@ -201,6 +217,32 @@ int idx2dindex(int ifidx, int socket) {
return i;
}
// http://git.pengutronix.de/?p=tools/libsocketcan.git;a=blob;f=src/libsocketcan.c;hb=HEAD
static int send_dump_request(int fd, int family, int type)
{
struct get_req {
struct nlmsghdr n;
struct rtgenmsg g;
} req;
memset(&req, 0, sizeof(req));
req.n.nlmsg_len = sizeof(req);
req.n.nlmsg_type = type;
req.n.nlmsg_flags = NLM_F_REQUEST | NLM_F_ROOT | NLM_F_MATCH;
req.n.nlmsg_pid = 0;
req.n.nlmsg_seq = 0;
req.g.rtgen_family = family;
return send(fd, (void *)&req, sizeof(req), 0);
}
/* altern:
void netlink_getlink(int nsock) from
http://centaur.sch.bme.hu/~leait/projects/openwrt/
http://centaur.sch.bme.hu/~leait/projects/openwrt/files/sample.c
*/
int main(int argc, char **argv)
{
fd_set rdfs;
@ -209,6 +251,7 @@ int main(int argc, char **argv)
useconds_t bridge_delay = 0;
unsigned char timestamp = 0;
unsigned char down_causes_exit = 1;
unsigned char report_down_up = 0;
unsigned char dropmonitor = 0;
unsigned char extra_msg_info = 0;
unsigned char silent = SILENT_INI;
@ -236,6 +279,10 @@ int main(int argc, char **argv)
struct timeval tv, last_tv;
struct timeval timeout, timeout_config = { 0, 0 }, *timeout_current = NULL;
FILE *logfile = NULL;
struct netlink_struc {
int s;
struct sockaddr_nl saddr;
} netlink_s;
signal(SIGTERM, sigterm);
signal(SIGHUP, sigterm);
@ -244,7 +291,7 @@ int main(int argc, char **argv)
last_tv.tv_sec = 0;
last_tv.tv_usec = 0;
while ((opt = getopt(argc, argv, "t:ciaSs:b:B:u:lDdxLn:r:heT:?")) != -1) {
while ((opt = getopt(argc, argv, "t:ciaSs:b:B:u:lDdxLn:Rr:heT:?")) != -1) {
switch (opt) {
case 't':
timestamp = optarg[0];
@ -363,6 +410,10 @@ int main(int argc, char **argv)
}
break;
case 'R':
report_down_up = 1;
break;
case 'T':
errno = 0;
timeout_config.tv_usec = strtol(optarg, NULL, 0);
@ -399,9 +450,21 @@ int main(int argc, char **argv)
silent = SILENT_OFF; /* default output */
}
// netlink to determine down/up
memset(&netlink_s.saddr, 0, sizeof(netlink_s.saddr));
netlink_s.saddr.nl_family = AF_NETLINK;
netlink_s.saddr.nl_groups = RTMGRP_LINK;
netlink_s.s = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
bind(netlink_s.s, (struct sockaddr *) &netlink_s.saddr, sizeof(netlink_s.saddr));
if (send_dump_request(netlink_s.s, AF_PACKET, RTM_GETLINK) < 0) {
perror("Cannot send dump request");
return ret;
}
//altern: netlink_getlink(netlink_s.s);
currmax = argc - optind; /* find real number of CAN devices */
if (currmax > MAXSOCK) {
if (currmax > MAXSOCK-1) { // minus one: one socket already used for netlink
fprintf(stderr, "More than %d CAN devices given on commandline!\n", MAXSOCK);
return 1;
}
@ -451,6 +514,7 @@ int main(int argc, char **argv)
exit(1);
}
addr.can_ifindex = ifr.ifr_ifindex;
idx2dindex(addr.can_ifindex, s[i]);
} else
addr.can_ifindex = 0; /* any can interface */
@ -623,6 +687,7 @@ int main(int argc, char **argv)
while (running) {
FD_ZERO(&rdfs);
FD_SET(netlink_s.s, &rdfs);
for (i=0; i<currmax; i++)
FD_SET(s[i], &rdfs);
@ -635,6 +700,43 @@ int main(int argc, char **argv)
continue;
}
// check netlink socket
if (FD_ISSET(netlink_s.s, &rdfs)) {
char buf[4096];
struct iovec iov = { buf, sizeof(buf) };
struct msghdr msg = { &netlink_s.saddr, sizeof(netlink_s.saddr), &iov, 1, NULL, 0, 0 };
int len = recvmsg(netlink_s.s, &msg, 0);
struct nlmsghdr *nh;
for (nh = (struct nlmsghdr *) buf; NLMSG_OK (nh, len); nh = NLMSG_NEXT (nh, len)) {
if (nh->nlmsg_type == NLMSG_DONE){
break;
}
if (nh->nlmsg_type == NLMSG_ERROR){
continue;
}
if (nh->nlmsg_type == RTM_NEWLINK) {
/*if (nh->nlmsg_type < RTM_NEWADDR){*/
struct ifinfomsg *rtif = NLMSG_DATA(nh);
if (is_idx_cached(rtif->ifi_index)) {
char ifname[IF_NAMESIZE];
if_indextoname(rtif->ifi_index, ifname);
const int will_exit = (down_causes_exit && !(rtif->ifi_flags&IFF_RUNNING));
if (report_down_up || will_exit) {
printf("#%*s is %s\n", max_devname_len, ifname,
(rtif->ifi_flags&IFF_RUNNING) ? "up" : "down");
fflush(stdout);
}
if (will_exit) {
return 1;
}
}
}
}
}
for (i=0; i<currmax; i++) { /* check all CAN RAW sockets */
if (FD_ISSET(s[i], &rdfs)) {
@ -647,16 +749,23 @@ int main(int argc, char **argv)
msg.msg_controllen = sizeof(ctrlmsg);
msg.msg_flags = 0;
idx = idx2dindex(addr.can_ifindex, s[i]);
nbytes = recvmsg(s[i], &msg, 0);
if (nbytes < 0) {
if ((errno == ENETDOWN) && !down_causes_exit) {
fprintf(stderr, "read: %s \t\t(not exiting because of -D flag)\n", strerror(errno));
if (errno == ENETDOWN) {
if (down_causes_exit) {
//if (!report_down_up) { /* no previous reporting message, so report here before exit */
printf("#%*s is down!\n", max_devname_len, devname[idx]);
//}
} else {
continue;
}
} else {
perror("read");
}
perror("read");
return 1;
}
if ((size_t)nbytes == CAN_MTU)
maxdlen = CAN_MAX_DLEN;
else if ((size_t)nbytes == CANFD_MTU)
@ -708,8 +817,6 @@ int main(int argc, char **argv)
last_dropcnt[i] = dropcnt[i];
}
idx = idx2dindex(addr.can_ifindex, s[i]);
/* once we detected a EFF frame indent SFF frames accordingly */
if (frame.can_id & CAN_EFF_FLAG)
view |= CANLIB_VIEW_INDENT_SFF;
@ -810,6 +917,7 @@ int main(int argc, char **argv)
}
}
close(netlink_s.s);
for (i=0; i<currmax; i++)
close(s[i]);