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/** @file proxy_tcp.c
    @brief xfrp proxy tcp implemented
    @author Copyright (C) 2016 Dengfeng Liu <liu_df@qq.com>
*/

#include <stdlib.h>
#include <stdio.h>
#include <assert.h>
#include <string.h>

#include <sys/socket.h>
#include <netinet/in.h>
#include <errno.h>
#include <syslog.h>
#include <unistd.h>

#include <event2/bufferevent.h>
#include <event2/buffer.h>
#include <event2/listener.h>
#include <event2/event.h>

#include "debug.h"
#include "uthash.h"
#include "common.h"
#include "proxy.h"
#include "config.h"
#include "tcpmux.h"

#define	BUF_LEN	2*1024

// read data from local service
void tcp_proxy_c2s_cb(struct bufferevent *bev, void *ctx)
{
	struct common_conf  *c_conf = get_common_config();
	struct proxy_client *client = (struct proxy_client *)ctx;
	assert(client);
	struct bufferevent *partner = client->ctl_bev;
	assert(partner);
	struct evbuffer *src = bufferevent_get_input(bev);
	size_t len = evbuffer_get_length(src);
	assert(len > 0);
	if (!c_conf->tcp_mux) {
		struct evbuffer *dst = bufferevent_get_output(partner);
		evbuffer_add_buffer(dst, src);
		return;
	}

	uint8_t *buf = (uint8_t *)malloc(len);
	assert(buf != NULL);
	memset(buf, 0, len);
	uint32_t nr = bufferevent_read(bev, buf, len);
	assert(nr == len);
	nr = tmux_stream_write(partner, buf, len, &client->stream);
	if (nr < len) {
		debug(LOG_DEBUG, "stream_id [%d] len is %d tmux_stream_write %d data, disable read", client->stream.id, len, nr);
		bufferevent_disable(bev, EV_READ);
	}
}

// read data from frps
// when tcp mux enable this function will not be used
void tcp_proxy_s2c_cb(struct bufferevent *bev, void *ctx)
{
	struct proxy_client *client = (struct proxy_client *)ctx;
	assert(client);
	struct bufferevent *partner = client->local_proxy_bev;
	assert(partner);
	struct evbuffer *src, *dst;
	src = bufferevent_get_input(bev);
	size_t len = evbuffer_get_length(src);
	assert(len > 0);
	dst = bufferevent_get_output(partner);
	evbuffer_add_buffer(dst, src);
}