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#include "proto.h"
#include "log.h"
#include <time.h>
#include <assert.h>
#include <errno.h>
void flush_messages(int sfd, struct message* cursor, const struct message* const end) {
dbg("Flushing %ld pending messages", end - cursor);
for(; cursor < end; cursor++) {
//now reply the client with the same data
int rc = sendto(sfd, cursor->payload, cursor->payload_len, 0, (const struct sockaddr*)&cursor->dest, cursor->dest_len);
if (rc < 0) {
fatal("Failed to send message");
}
}
}
int main(int argc, char** argv) {
struct message outbuff[10] = {0};
struct dht dht;
dht.self = (struct nodeid){.inner={0x0034048f, 0x08000020, 0x00888880, 0x02008460, 0x0ab00521}};
struct message* message_cursor = outbuff;
proto_begin(&dht, time(NULL), &message_cursor, outbuff+10);
flush_messages(dht.sfd, outbuff, message_cursor);
char buff_storage[2049];
int rc = 0;
while(rc == 0) {
char* buff = buff_storage;
printf("Waiting for data...");
fflush(stdout);
bool timedout = false;
if(!dht.pause){
struct entry* oldest;
routing_oldest(&oldest);
if(oldest != NULL) {
dbg("Set timeout to %ld", oldest->expire - time(NULL));
struct timeval tv = {
.tv_sec = oldest->expire - time(NULL),
.tv_usec = 0,
};
if(tv.tv_sec <= 0) {
timedout = true;
} else {
setsockopt(dht.sfd, SOL_SOCKET, SO_RCVTIMEO, &tv, sizeof(tv));
}
}
} else {
printf("DHT timeout is paused");
}
// Try to receive some data, this is a blocking call
struct sockaddr_storage remote;
socklen_t remote_len = sizeof(remote);
ssize_t recv_len;
if(!timedout) {
recv_len = recvfrom(dht.sfd, buff, 2048, 0, (struct sockaddr *)&remote, &remote_len);
if(recv_len == -1) {
// This is really strange. The man pages say we should be getting
// an ETIMEDOUT here, but instead linux gives us this.
if(errno == EAGAIN) {
buff = NULL;
recv_len = 0;
} else {
fatal("RECV failed %d %m", errno, errno);
}
} else if(recv_len >= 2048) {
fatal("Receive buffer too small");
}
// Null terminate the packet
if(buff != NULL) {
buff[recv_len] = '\0';
}
} else {
buff = NULL;
recv_len = 0;
}
struct message* message_cursor = outbuff;
time_t now = time(NULL);
rc = proto_run(&dht, buff, recv_len, (struct sockaddr_in*)&remote, remote_len, now, &message_cursor, outbuff+10);
flush_messages(dht.sfd, outbuff, message_cursor);
}
proto_end(&dht);
return rc;
}
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