nghttp2/examples/shrpx_downstream_connection.cc

185 lines
6.0 KiB
C++

/*
* Spdylay - SPDY Library
*
* Copyright (c) 2012 Tatsuhiro Tsujikawa
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#include "shrpx_downstream_connection.h"
#include "shrpx_client_handler.h"
#include "shrpx_upstream.h"
#include "shrpx_downstream.h"
#include "shrpx_config.h"
#include "shrpx_error.h"
namespace shrpx {
// Workaround for the inability for Bufferevent to remove timeout from
// bufferevent. Specify this long timeout instead of removing.
namespace {
timeval max_timeout = { 86400, 0 };
} // namespace
DownstreamConnection::DownstreamConnection(ClientHandler *client_handler)
: client_handler_(client_handler),
bev_(0),
downstream_(0)
{
}
DownstreamConnection::~DownstreamConnection()
{
if(bev_) {
bufferevent_disable(bev_, EV_READ | EV_WRITE);
bufferevent_free(bev_);
}
// Downstream and DownstreamConnection may be deleted
// asynchronously.
if(downstream_) {
downstream_->set_downstream_connection(0);
}
}
int DownstreamConnection::attach_downstream(Downstream *downstream)
{
if(ENABLE_LOG) {
LOG(INFO) << "Attaching downstream connection " << this << " to "
<< "downstream " << downstream;
}
Upstream *upstream = downstream->get_upstream();
if(!bev_) {
event_base *evbase = client_handler_->get_evbase();
bev_ = bufferevent_socket_new
(evbase, -1,
BEV_OPT_CLOSE_ON_FREE | BEV_OPT_DEFER_CALLBACKS);
int rv = bufferevent_socket_connect
(bev_,
// TODO maybe not thread-safe?
const_cast<sockaddr*>(&get_config()->downstream_addr.sa),
get_config()->downstream_addrlen);
if(rv != 0) {
bufferevent_free(bev_);
bev_ = 0;
return SHRPX_ERR_NETWORK;
}
if(ENABLE_LOG) {
LOG(INFO) << "Connecting to downstream server " << this;
}
}
downstream->set_downstream_connection(this);
downstream_ = downstream;
bufferevent_setwatermark(bev_, EV_READ, 0, SHRPX_READ_WARTER_MARK);
bufferevent_enable(bev_, EV_READ);
bufferevent_setcb(bev_,
upstream->get_downstream_readcb(),
upstream->get_downstream_writecb(),
upstream->get_downstream_eventcb(), this);
// HTTP request/response model, we first issue request to downstream
// server, so just enable write timeout here.
bufferevent_set_timeouts(bev_,
&max_timeout,
&get_config()->downstream_write_timeout);
return 0;
}
// When downstream request is issued, call this function to set read
// timeout. We don't know when the request is completely received by
// the downstream server. This function may be called before that
// happens. Overall it does not cause problem for most of the time.
// If the downstream server is too slow to recv/send, the connection
// will be dropped by read timeout.
void DownstreamConnection::start_waiting_response()
{
if(bev_) {
bufferevent_set_timeouts(bev_,
&get_config()->downstream_read_timeout,
&get_config()->downstream_write_timeout);
}
}
namespace {
// Gets called when DownstreamConnection is pooled in ClientHandler.
void idle_eventcb(bufferevent *bev, short events, void *arg)
{
DownstreamConnection *dconn = reinterpret_cast<DownstreamConnection*>(arg);
if(events & BEV_EVENT_CONNECTED) {
// Downstream was detached before connection established?
// This may be safe to be left.
if(ENABLE_LOG) {
LOG(INFO) << "Idle downstream connected?" << dconn;
}
return;
}
if(events & BEV_EVENT_EOF) {
if(ENABLE_LOG) {
LOG(INFO) << "Idle downstream connection EOF " << dconn;
}
} else if(events & BEV_EVENT_TIMEOUT) {
if(ENABLE_LOG) {
LOG(INFO) << "Idle downstream connection timeout " << dconn;
}
} else if(events & BEV_EVENT_ERROR) {
if(ENABLE_LOG) {
LOG(INFO) << "Idle downstream connection error " << dconn;
}
}
ClientHandler *client_handler = dconn->get_client_handler();
client_handler->remove_downstream_connection(dconn);
delete dconn;
}
} // namespace
void DownstreamConnection::detach_downstream(Downstream *downstream)
{
if(ENABLE_LOG) {
LOG(INFO) << "Detaching downstream connection " << this << " from "
<< "downstream " << downstream;
}
downstream->set_downstream_connection(0);
downstream_ = 0;
bufferevent_enable(bev_, EV_READ);
bufferevent_setcb(bev_, 0, 0, idle_eventcb, this);
// On idle state, just enable read timeout. Normally idle downstream
// connection will get EOF from the downstream server and closed.
bufferevent_set_timeouts(bev_,
&get_config()->downstream_idle_read_timeout,
&get_config()->downstream_write_timeout);
client_handler_->pool_downstream_connection(this);
}
ClientHandler* DownstreamConnection::get_client_handler()
{
return client_handler_;
}
Downstream* DownstreamConnection::get_downstream()
{
return downstream_;
}
bufferevent* DownstreamConnection::get_bev()
{
return bev_;
}
} // namespace shrpx