static void try_connect(h2o_socketpool_connect_request_t *req)
{
h2o_socketpool_target_t *target;
req->remaining_try_count--;
if (req->lb.tried != NULL) {
if (req->pool->targets.size > 1) {
req->selected_target = req->pool->balancer->callbacks->select_(req->pool->balancer, &req->pool->targets, req->lb.tried);
assert(!req->lb.tried[req->selected_target]);
req->lb.tried[req->selected_target] = 1;
__sync_add_and_fetch(&req->pool->targets.entries[req->selected_target]->_shared.leased_count, 1);
} else {
req->selected_target = 0;
}
}
target = req->pool->targets.entries[req->selected_target];
switch (target->type) {
case H2O_SOCKETPOOL_TYPE_NAMED:
/* resolve the name, and connect */
req->getaddr_req = h2o_hostinfo_getaddr(req->getaddr_receiver, target->url.host, target->peer.named_serv, AF_UNSPEC,
SOCK_STREAM, IPPROTO_TCP, AI_ADDRCONFIG | AI_NUMERICSERV, on_getaddr, req);
break;
case H2O_SOCKETPOOL_TYPE_SOCKADDR:
/* connect (using sockaddr_in) */
start_connect(req, (void *)&target->peer.sockaddr.bytes, target->peer.sockaddr.len);
break;
}
}
void h2o_socketpool_connect(h2o_socketpool_connect_request_t **_req, h2o_socketpool_t *pool, h2o_loop_t *loop,
h2o_multithread_receiver_t *getaddr_receiver, h2o_socketpool_connect_cb cb, void *data)
{
struct pool_entry_t *entry = NULL;
if (_req != NULL)
*_req = NULL;
/* fetch an entry and return it */
pthread_mutex_lock(&pool->_shared.mutex);
destroy_expired(pool);
while (1) {
if (h2o_linklist_is_empty(&pool->_shared.sockets))
break;
entry = H2O_STRUCT_FROM_MEMBER(struct pool_entry_t, link, pool->_shared.sockets.next);
h2o_linklist_unlink(&entry->link);
pthread_mutex_unlock(&pool->_shared.mutex);
/* test if the connection is still alive */
char buf[1];
ssize_t rret = recv(entry->sockinfo.fd, buf, 1, MSG_PEEK);
if (rret == -1 && (errno == EAGAIN || errno == EWOULDBLOCK)) {
/* yes! return it */
h2o_socket_t *sock = h2o_socket_import(loop, &entry->sockinfo);
free(entry);
sock->on_close.cb = on_close;
sock->on_close.data = pool;
cb(sock, NULL, data);
return;
}
/* connection is dead, report, close, and retry */
if (rret <= 0) {
static long counter = 0;
if (__sync_fetch_and_add(&counter, 1) == 0)
fprintf(stderr, "[WARN] detected close by upstream before the expected timeout (see issue #679)\n");
} else {
static long counter = 0;
if (__sync_fetch_and_add(&counter, 1) == 0)
fprintf(stderr, "[WARN] unexpectedly received data to a pooled socket (see issue #679)\n");
}
destroy_detached(entry);
pthread_mutex_lock(&pool->_shared.mutex);
}
pthread_mutex_unlock(&pool->_shared.mutex);
/* FIXME repsect `capacity` */
__sync_add_and_fetch(&pool->_shared.count, 1);
/* prepare request object */
h2o_socketpool_connect_request_t *req = h2o_mem_alloc(sizeof(*req));
*req = (h2o_socketpool_connect_request_t){data, cb, pool, loop};
if (_req != NULL)
*_req = req;
switch (pool->type) {
case H2O_SOCKETPOOL_TYPE_NAMED:
/* resolve the name, and connect */
req->getaddr_req = h2o_hostinfo_getaddr(getaddr_receiver, pool->peer.host, pool->peer.named_serv, AF_UNSPEC, SOCK_STREAM,
IPPROTO_TCP, AI_ADDRCONFIG | AI_NUMERICSERV, on_getaddr, req);
break;
case H2O_SOCKETPOOL_TYPE_SOCKADDR:
/* connect (using sockaddr_in) */
start_connect(req, (void *)&pool->peer.sockaddr.bytes, pool->peer.sockaddr.len);
break;
}
}
