nortti
/
ethermess
1
0
Fork 0
Code Issues Pull Requests Releases 1 Wiki Activity

Send our own status periodically

This commit is contained in:
Juhani Krekelä 2019-07-09 17:18:00 +03:00
parent 541dd28a64
commit f678c5054f
1 changed files with 37 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

38
ethermess.c
View File

@ -5,6 +5,7 @@
#include <errno.h>
#include <fcntl.h>
#include <inttypes.h>
#include <limits.h>
#include <linux/if_packet.h>
#include <net/ethernet.h>
#include <net/if.h>
@ -19,6 +20,7 @@
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <time.h>
#include <unistd.h>
#define EM_PROTOCOL_VERSION 0
@ -43,6 +45,7 @@ unsigned char broadcast_mac[6] = {0xff, 0xff, 0xff, 0xff, 0xff, 0xff};
unsigned char own_status = EMS_AVAILABLE;
unsigned char own_nick[256] = {'n', 'o', 'r', 't', 't', 'i'};
unsigned char own_nick_length = 6;
time_t next_status_broadcast;
bool own_message_queued = false;
unsigned char own_message_destination_mac[6];
@ -101,6 +104,15 @@ unsigned char random_byte(void) {
return randomness;
}
time_t monotonic_time(void) {
struct timespec now;
errno = 0;
if (clock_gettime(CLOCK_MONOTONIC, &now) == -1) {
err(1, "clock_gettime");
}
return now.tv_sec;
}
char hexify(int nybble) {
assert(0 <= nybble && nybble <= 16);
return "0123456789abcdef"[nybble];
@ -451,8 +463,26 @@ void eventloop(void) {
pollfds[1].events = POLLIN;
while (running) {
// Figure out how many ms to wait
int wait_ms;
time_t now = monotonic_time();
if (next_status_broadcast <= now) {
// The time has come to send the status broadcast
send_status(broadcast_mac);
// Do next one in 5 minutes
next_status_broadcast = now + 5 * 60;
} else {
if (INT_MAX / 1000 >= next_status_broadcast - now) {
// Wail until next status broadcast is due
wait_ms = (next_status_broadcast - now) * 1000;
} else {
// Would overflow, wait INT_MAX ms
wait_ms = INT_MAX;
}
}
errno = 0;
int ready = poll(pollfds, sizeof(pollfds) / sizeof(*pollfds), -1);
int ready = poll(pollfds, sizeof(pollfds) / sizeof(*pollfds), wait_ms);
if (ready == -1) {
err(1, "poll");
}
@ -545,6 +575,12 @@ int main(int argc, char **argv) {
// Initialize the message id cache
memset(msgid_cache, 0, sizeof(msgid_cache));
// Broadcast our status to the network to let them know we're here
send_status(broadcast_mac);
// Schedule next broadcast of our status 5 min in the future
next_status_broadcast = monotonic_time() + 5 * 60;
// Request status from everyone, so that we can get an idea of who is on the network
send_status_request(broadcast_mac);