Files
adsb-tools/outgoing.c

122 lines
4.0 KiB
C

#include <stdio.h>
#include <assert.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>
#include "common.h"
#include "outgoing.h"
struct outgoing {
struct peer peer;
char id[UUID_LEN];
const char *node;
const char *service;
struct addrinfo *addrs;
struct addrinfo *addr;
outgoing_connection_handler handler;
void *passthrough;
};
static void outgoing_connect_result(struct outgoing *, int);
static void outgoing_resolve(struct outgoing *);
static void outgoing_connect_next(struct outgoing *outgoing) {
if (outgoing->addr == NULL) {
freeaddrinfo(outgoing->addrs);
fprintf(stderr, "O %s: Can't connect to any addresses of %s/%s\n", outgoing->id, outgoing->node, outgoing->service);
// TODO: timed retry
return;
}
char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV];
assert(getnameinfo(outgoing->addr->ai_addr, outgoing->addr->ai_addrlen, hbuf, sizeof(hbuf), sbuf, sizeof(sbuf), NI_NUMERICHOST | NI_NUMERICSERV) == 0);
fprintf(stderr, "O %s: Connecting to %s/%s...\n", outgoing->id, hbuf, sbuf);
outgoing->peer.fd = socket(outgoing->addr->ai_family, outgoing->addr->ai_socktype | SOCK_NONBLOCK, outgoing->addr->ai_protocol);
assert(outgoing->peer.fd >= 0);
int result = connect(outgoing->peer.fd, outgoing->addr->ai_addr, outgoing->addr->ai_addrlen);
outgoing_connect_result(outgoing, result == 0 ? result : errno);
}
static void outgoing_connect_handler(struct peer *peer) {
struct outgoing *outgoing = (struct outgoing *) peer;
peer_epoll_del(&outgoing->peer);
int error;
socklen_t len = sizeof(error);
assert(getsockopt(outgoing->peer.fd, SOL_SOCKET, SO_ERROR, &error, &len) == 0);
outgoing_connect_result(outgoing, error);
}
static void outgoing_disconnect_handler(struct peer *peer) {
struct outgoing *outgoing = (struct outgoing *) peer;
close(outgoing->peer.fd);
fprintf(stderr, "O %s: Peer disconnected; reconnecting...\n", outgoing->id);
outgoing_resolve(outgoing);
}
static void outgoing_connect_result(struct outgoing *outgoing, int result) {
char hbuf[NI_MAXHOST], sbuf[NI_MAXSERV];
assert(getnameinfo(outgoing->addr->ai_addr, outgoing->addr->ai_addrlen, hbuf, sizeof(hbuf), sbuf, sizeof(sbuf), NI_NUMERICHOST | NI_NUMERICSERV) == 0);
switch (result) {
case 0:
fprintf(stderr, "O %s: Connected to %s/%s\n", outgoing->id, hbuf, sbuf);
freeaddrinfo(outgoing->addrs);
// We listen for just hangup on this fd. We pass a duplicate to the handler, so our epoll setings are independent.
outgoing->peer.event_handler = outgoing_disconnect_handler;
peer_epoll_add((struct peer *) outgoing, EPOLLRDHUP);
outgoing->handler(dup(outgoing->peer.fd), outgoing->passthrough);
break;
case EINPROGRESS:
outgoing->peer.event_handler = outgoing_connect_handler;
peer_epoll_add((struct peer *) outgoing, EPOLLOUT);
break;
default:
fprintf(stderr, "O %s: Can't connect to %s/%s: %s\n", outgoing->id, hbuf, sbuf, strerror(result));
close(outgoing->peer.fd);
outgoing->addr = outgoing->addr->ai_next;
// Tail recursion :/
outgoing_connect_next(outgoing);
break;
}
}
static void outgoing_resolve(struct outgoing *outgoing) {
fprintf(stderr, "O %s: Resolving %s/%s...\n", outgoing->id, outgoing->node, outgoing->service);
struct addrinfo hints = {
.ai_family = AF_UNSPEC,
.ai_socktype = SOCK_STREAM,
};
int gai_err = getaddrinfo(outgoing->node, outgoing->service, &hints, &outgoing->addrs);
if (gai_err) {
fprintf(stderr, "O %s: Failed to resolve %s/%s: %s\n", outgoing->id, outgoing->node, outgoing->service, gai_strerror(gai_err));
// TODO: timed retry
return;
}
outgoing->addr = outgoing->addrs;
outgoing_connect_next(outgoing);
}
void outgoing_new(const char *node, const char *service, outgoing_connection_handler handler, void *passthrough) {
struct outgoing *outgoing = malloc(sizeof(*outgoing));
uuid_gen(outgoing->id);
outgoing->node = node;
outgoing->service = service;
outgoing->handler = handler;
outgoing->passthrough = passthrough;
outgoing_resolve(outgoing);
}