void UdevMonitor::addTagFilter(const char* tag)
{
/* Add a tag filter: */
if(udev_monitor_filter_add_match_tag(monitor,tag)!=0)
throw std::runtime_error("RawHID::UdevMonitor::addTagFilter: Internal libudev error");
/* If the monitor is already listening, update its filters: */
if(listening)
if(udev_monitor_filter_update(monitor)!=0)
throw std::runtime_error("RawHID::UdevMonitor::addTagFilter: Internal libudev error");
}
static int adm_monitor(struct udev *udev, int argc, char *argv[]) {
struct sigaction act = {};
sigset_t mask;
bool prop = false;
bool print_kernel = false;
bool print_udev = false;
_cleanup_udev_list_cleanup_ struct udev_list subsystem_match_list;
_cleanup_udev_list_cleanup_ struct udev_list tag_match_list;
_cleanup_udev_monitor_unref_ struct udev_monitor *udev_monitor = NULL;
_cleanup_udev_monitor_unref_ struct udev_monitor *kernel_monitor = NULL;
_cleanup_close_ int fd_ep = -1;
int fd_kernel = -1, fd_udev = -1;
struct epoll_event ep_kernel, ep_udev;
int c;
static const struct option options[] = {
{ "property", no_argument, NULL, 'p' },
{ "environment", no_argument, NULL, 'e' }, /* alias for -p */
{ "kernel", no_argument, NULL, 'k' },
{ "udev", no_argument, NULL, 'u' },
{ "subsystem-match", required_argument, NULL, 's' },
{ "tag-match", required_argument, NULL, 't' },
{ "help", no_argument, NULL, 'h' },
{}
};
udev_list_init(udev, &subsystem_match_list, true);
udev_list_init(udev, &tag_match_list, true);
while ((c = getopt_long(argc, argv, "pekus:t:h", options, NULL)) >= 0)
switch (c) {
case 'p':
case 'e':
prop = true;
break;
case 'k':
print_kernel = true;
break;
case 'u':
print_udev = true;
break;
case 's':
{
char subsys[UTIL_NAME_SIZE];
char *devtype;
strscpy(subsys, sizeof(subsys), optarg);
devtype = strchr(subsys, '/');
if (devtype != NULL) {
devtype[0] = '\0';
devtype++;
}
udev_list_entry_add(&subsystem_match_list, subsys, devtype);
break;
}
case 't':
udev_list_entry_add(&tag_match_list, optarg, NULL);
break;
case 'h':
help();
return 0;
default:
return 1;
}
if (!print_kernel && !print_udev) {
print_kernel = true;
print_udev = true;
}
/* set signal handlers */
act.sa_handler = sig_handler;
act.sa_flags = SA_RESTART;
sigaction(SIGINT, &act, NULL);
sigaction(SIGTERM, &act, NULL);
sigemptyset(&mask);
sigaddset(&mask, SIGINT);
sigaddset(&mask, SIGTERM);
sigprocmask(SIG_UNBLOCK, &mask, NULL);
/* Callers are expecting to see events as they happen: Line buffering */
setlinebuf(stdout);
fd_ep = epoll_create1(EPOLL_CLOEXEC);
if (fd_ep < 0) {
log_error_errno(errno, "error creating epoll fd: %m");
return 1;
}
printf("monitor will print the received events for:\n");
if (print_udev) {
struct udev_list_entry *entry;
udev_monitor = udev_monitor_new_from_netlink(udev, "udev");
if (udev_monitor == NULL) {
fprintf(stderr, "error: unable to create netlink socket\n");
return 1;
}
udev_monitor_set_receive_buffer_size(udev_monitor, 128*1024*1024);
fd_udev = udev_monitor_get_fd(udev_monitor);
udev_list_entry_foreach(entry, udev_list_get_entry(&subsystem_match_list)) {
const char *subsys = udev_list_entry_get_name(entry);
const char *devtype = udev_list_entry_get_value(entry);
if (udev_monitor_filter_add_match_subsystem_devtype(udev_monitor, subsys, devtype) < 0)
fprintf(stderr, "error: unable to apply subsystem filter '%s'\n", subsys);
}
udev_list_entry_foreach(entry, udev_list_get_entry(&tag_match_list)) {
const char *tag = udev_list_entry_get_name(entry);
if (udev_monitor_filter_add_match_tag(udev_monitor, tag) < 0)
fprintf(stderr, "error: unable to apply tag filter '%s'\n", tag);
}
if (udev_monitor_enable_receiving(udev_monitor) < 0) {
fprintf(stderr, "error: unable to subscribe to udev events\n");
return 2;
}
memzero(&ep_udev, sizeof(struct epoll_event));
ep_udev.events = EPOLLIN;
ep_udev.data.fd = fd_udev;
if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_udev, &ep_udev) < 0) {
log_error_errno(errno, "fail to add fd to epoll: %m");
return 2;
}
printf("UDEV - the event which udev sends out after rule processing\n");
}
if (print_kernel) {
struct udev_list_entry *entry;
kernel_monitor = udev_monitor_new_from_netlink(udev, "kernel");
if (kernel_monitor == NULL) {
fprintf(stderr, "error: unable to create netlink socket\n");
return 3;
}
udev_monitor_set_receive_buffer_size(kernel_monitor, 128*1024*1024);
fd_kernel = udev_monitor_get_fd(kernel_monitor);
udev_list_entry_foreach(entry, udev_list_get_entry(&subsystem_match_list)) {
const char *subsys = udev_list_entry_get_name(entry);
if (udev_monitor_filter_add_match_subsystem_devtype(kernel_monitor, subsys, NULL) < 0)
fprintf(stderr, "error: unable to apply subsystem filter '%s'\n", subsys);
}
if (udev_monitor_enable_receiving(kernel_monitor) < 0) {
fprintf(stderr, "error: unable to subscribe to kernel events\n");
return 4;
}
memzero(&ep_kernel, sizeof(struct epoll_event));
ep_kernel.events = EPOLLIN;
ep_kernel.data.fd = fd_kernel;
if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_kernel, &ep_kernel) < 0) {
log_error_errno(errno, "fail to add fd to epoll: %m");
return 5;
}
printf("KERNEL - the kernel uevent\n");
}
printf("\n");
while (!udev_exit) {
int fdcount;
struct epoll_event ev[4];
int i;
fdcount = epoll_wait(fd_ep, ev, ELEMENTSOF(ev), -1);
if (fdcount < 0) {
if (errno != EINTR)
fprintf(stderr, "error receiving uevent message: %m\n");
continue;
}
for (i = 0; i < fdcount; i++) {
if (ev[i].data.fd == fd_kernel && ev[i].events & EPOLLIN) {
struct udev_device *device;
device = udev_monitor_receive_device(kernel_monitor);
if (device == NULL)
continue;
print_device(device, "KERNEL", prop);
udev_device_unref(device);
} else if (ev[i].data.fd == fd_udev && ev[i].events & EPOLLIN) {
struct udev_device *device;
device = udev_monitor_receive_device(udev_monitor);
if (device == NULL)
continue;
print_device(device, "UDEV", prop);
udev_device_unref(device);
}
}
}
return 0;
}
