How to manipulate libevent bufferevents outside of callbacks - c++

Question

I use libevent to write client-server application, on client side i want to continiusly wait for intput from console. I tried to run event_base_dispatch in thread, and in main thread ask for input string and add it to bufferevent.
std::thread libevthr(libev_start, base);
std::string s;
do
{
cin >> s;
bufferevent_write(bev, "Hello, world!", 13);
} while(s != "xxx");
libevthr.join();
For some reason this doesn't work, but if i put bufferevent_write inside one of callbacks, it works fine
void event_cb(struct bufferevent *bev, short events, void *ptr)
{
if (events & BEV_EVENT_CONNECTED) {
/* We're connected to 127.0.0.1 Ordinarily we'd do
something here, like start reading or writing. */
bufferevent_write(bev, "Hello, world!", 13);
std::cout << "Connected" << std::endl;
}
if (events & BEV_EVENT_ERROR) {
if (EVUTIL_SOCKET_ERROR() == 10054)
cout << "Server stopped working!" << endl;
else
cout << "Error has happened" << endl;
}
if (events & (BEV_EVENT_EOF | BEV_EVENT_ERROR))
{
bufferevent_free(bev);
}
}
Can you explain how should i write this correctly?
Sorry if i have any mistakes in english.
Full code here:
#include "UClient.h"
#include <iostream>
#include "event2/event.h"
#include "event2/listener.h"
#include "event2/bufferevent.h"
#include "event2/buffer.h"
#include <thread>
using std::cout, std::cin, std::endl;
void event_cb(struct bufferevent *bev, short events, void *ptr)
{
if (events & BEV_EVENT_CONNECTED) {
/* We're connected to 127.0.0.1 Ordinarily we'd do
something here, like start reading or writing. */
bufferevent_write(bev, "Hello, world!", 13);
std::cout << "Connected" << std::endl;
}
if (events & BEV_EVENT_ERROR) {
if (EVUTIL_SOCKET_ERROR() == 10054)
cout << "Server stopped working!" << endl;
else
cout << "Error has happened" << endl;
}
if (events & (BEV_EVENT_EOF | BEV_EVENT_ERROR))
{
bufferevent_free(bev);
}
}
void write_cb(struct bufferevent *bev, void *ctx)
{
cout << 'Data was written' << endl;
}
void libev_start(event_base *base)
{
event_base_dispatch(base);
}
int main()
{
int port = 9554;
struct event_base *base;
struct bufferevent *bev;
struct sockaddr_in cl_inf;
if (!initWinsock()) {
perror("Failed to initialize Winsock");
return 1;
}
base = event_base_new();
ZeroMemory(&cl_inf, sizeof(cl_inf));
in_addr serv_ip;
inet_pton(AF_INET, "127.0.0.1", &serv_ip);
cl_inf.sin_family = AF_INET;
cl_inf.sin_addr = serv_ip;
cl_inf.sin_port = htons(port);
bev = bufferevent_socket_new(base, -1, BEV_OPT_CLOSE_ON_FREE);
bufferevent_setcb(bev, NULL, write_cb, event_cb, NULL);
if (bufferevent_socket_connect(bev,
(struct sockaddr *)&cl_inf, sizeof(cl_inf)) < 0) {
/* Error starting connection */
std::cout << "Can't connect to server!" << std::endl;
bufferevent_free(bev);
return -1;
}
bufferevent_enable(bev, EV_READ | EV_WRITE);
std::thread libevthr(libev_start, base);
std::string s;
do
{
cin >> s;
} while(s != "xxx");
libevthr.join();
std::cout << "client finished working";
return 0;
}