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#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <string.h>
#include <stdint.h>
#include <errno.h>
#include <signal.h>
#include <evhtp.h>
int
make_request(evbase_t * evbase,
evthr_t * evthr,
const char * const host,
const short port,
const char * const path,
evhtp_headers_t * headers,
evhtp_callback_cb cb,
void * arg) {
evhtp_connection_t * conn;
evhtp_request_t * request;
conn = evhtp_connection_new(evbase, host, port);
conn->thread = evthr;
request = evhtp_request_new(cb, arg);
evhtp_headers_add_header(request->headers_out,
evhtp_header_new("Host", "localhost", 0, 0));
evhtp_headers_add_header(request->headers_out,
evhtp_header_new("User-Agent", "libevhtp", 0, 0));
evhtp_headers_add_header(request->headers_out,
evhtp_header_new("Connection", "close", 0, 0));
evhtp_headers_add_headers(request->headers_out, headers);
printf("Making backend request...\n");
evhtp_make_request(conn, request, htp_method_GET, path);
printf("Ok.\n");
return 0;
}
static void
backend_cb(evhtp_request_t * backend_req, void * arg) {
evhtp_request_t * frontend_req = (evhtp_request_t *)arg;
evbuffer_prepend_buffer(frontend_req->buffer_out, backend_req->buffer_in);
evhtp_headers_add_headers(frontend_req->headers_out, backend_req->headers_in);
/*
* char body[1024] = { '\0' };
* ev_ssize_t len = evbuffer_copyout(frontend_req->buffer_out, body, sizeof(body));
* printf("Backend %zu: %s\n", len, body);
*/
evhtp_send_reply(frontend_req, EVHTP_RES_OK);
evhtp_request_resume(frontend_req);
}
static void
frontend_cb(evhtp_request_t * req, void * arg) {
int * aux;
int thr;
aux = (int *)evthr_get_aux(req->conn->thread);
thr = *aux;
printf(" Received frontend request on thread %d... ", thr);
/* Pause the frontend request while we run the backend requests. */
evhtp_request_pause(req);
make_request(evthr_get_base(req->conn->thread),
req->conn->thread,
"127.0.0.1", 80,
req->uri->path->full,
req->headers_in, backend_cb, req);
printf("Ok.\n");
}
/* Terminate gracefully on SIGTERM */
void
sigterm_cb(int fd, short event, void * arg) {
evbase_t * evbase = (evbase_t *)arg;
struct timeval tv = { .tv_usec = 100000, .tv_sec = 0 }; /* 100 ms */
event_base_loopexit(evbase, &tv);
}
void
init_thread_cb(evhtp_t * htp, evthr_t * thr, void * arg) {
static int aux = 0;
printf("Spinning up a thread: %d\n", ++aux);
evthr_set_aux(thr, &aux);
}
int
main(int argc, char ** argv) {
struct event *ev_sigterm;
evbase_t * evbase = event_base_new();
evhtp_t * evhtp = evhtp_new(evbase, NULL);
evhtp_set_gencb(evhtp, frontend_cb, NULL);
#if 0
#ifndef EVHTP_DISABLE_SSL
evhtp_ssl_cfg_t scfg1 = { 0 };
scfg1.pemfile = "./server.pem";
scfg1.privfile = "./server.pem";
evhtp_ssl_init(evhtp, &scfg1);
#endif
#endif
evhtp_use_threads_wexit(evhtp, init_thread_cb, NULL, 8, NULL);
#ifndef WIN32
ev_sigterm = evsignal_new(evbase, SIGTERM, sigterm_cb, evbase);
evsignal_add(ev_sigterm, NULL);
#endif
evhtp_bind_socket(evhtp, "0.0.0.0", 8081, 1024);
event_base_loop(evbase, 0);
printf("Clean exit\n");
return 0;
}
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