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/**
* Simple callee example (web browser is caller). Sends video to caller upon
* incoming calls.
*/
#include <errno.h> // errno
#include <poll.h>
#include <signal.h>
#include <stdbool.h>
#include <stdio.h> // printf
#include <string.h>
#include <unistd.h>
#include <netdb.h>
#include <sys/socket.h>
#include <sys/types.h>
#include "urtc.h"
// STUN servers
const char *stun[] = {
"stun.liburtc.org",
NULL
};
static int http_connect(const char *hostname) {
int err, fd;
struct addrinfo *res, *res0;
struct addrinfo hints = {
.ai_family = AF_UNSPEC,
.ai_socktype = SOCK_STREAM,
.ai_protocol = IPPROTO_TCP
};
// resolve hostname to IPv4/IPv6 address
if (err = getaddrinfo(hostname, "http", &hints, &res0), err) {
fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(errno));
return -1;
}
for (res = res0; res; res = res->ai_next) {
// attempt to open socket
fd = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
if (-1 == fd) {
continue; // failed. onto the next result.
}
// attempt to connect socket
if (-1 == connect(fd, res->ai_addr, res->ai_addrlen)) {
close(fd);
fd = -1;
continue; // failed. onto the next result.
}
break; // success. return.
}
// free resolved addresses
freeaddrinfo(res0);
return fd;
}
static int http_post(
const char *hostname,
const char *path,
const char *body
) {
const char *tmpl =
"POST %s HTTP/1.0\r\n"
"Host: %s\r\n"
"Content-Length: %d\r\n"
"Content-Type: text/plain\r\n"
"\r\n";
int fd, rv = -1;
char req[128];
if (fd = http_connect(hostname), -1 == fd) {
return -1;
}
// construct request
if (-1 == snprintf(req, sizeof(req), tmpl, path, hostname, strlen(body))) {
fprintf(stderr, "bad request template\n");
goto _unwind_socket;
}
// send request
if (rv = send(fd, req, strlen(req), 0), -1 == rv) {
perror("send");
goto _unwind_socket;
}
// send request body
if (rv = send(fd, body, strlen(body), 0), -1 == rv) {
perror("send");
goto _unwind_socket;
}
_unwind_socket:
shutdown(fd, SHUT_RDWR);
close(fd);
_done:
return rv;
}
/**
* HTTP GET request
*
* Resolves simple signaling server hostname to IPv4/IPv6 address and connects
* to its HTTP port.
*
* \param[out] response Buffer into which response is written.
* \param[in] size Max size of response.
* \param hostname Server hostname (e.g. "demo.liburtc.org")
* \param path HTTP path (e.g. "/offer")
*
* \return Socket file descriptor, or -1 on error. Caller must close file
* descriptor.
*/
static int get(
char *response,
size_t size,
const char *hostname,
const char *path
) {
const char *tmpl =
"GET %s HTTP/1.0\r\n"
"Host: %s\r\n"
"\r\n";
int err, fd, rv = -1;
char req[128];
if (fd = http_connect(hostname), -1 == fd) {
return -1;
}
// construct request
if (-1 == snprintf(req, sizeof(req), tmpl, path, hostname)) {
fprintf(stderr, "bad request template\n");
goto _unwind_socket;
}
// send request
if (rv = send(fd, req, strlen(req), 0), -1 == rv) {
perror("send");
goto _unwind_socket;
}
// get response
if (rv = recv(fd, response, size, 0), -1 == rv) {
perror("recv");
goto _unwind_socket;
}
_unwind_socket:
shutdown(fd, SHUT_RDWR);
close(fd);
_done:
return rv;
}
/**
* (callback) Handles incoming ICE candidates.
*
* \param cand[in] ICE candidate.
* \param arg[in] User argument.
*/
void handle_ice_candidate(const char *cand, void *arg) {
urtc_peerconn_t *pc = (urtc_peerconn_t *)arg;
urtc_add_ice_candidate(pc, cand);
}
static int longpoll(char *response, size_t size, const char *path) {
int n;
while (true) {
n = get(response, size, "demo.liburtc.org", path);
if (-1 == n || 0 == n) {
perror("get");
continue;
}
// blindly strip http headers
char *body = strstr(response, "\r\n\r\n");
strcpy(response, body + 4);
// ignore empty responses (i.e. long-poll timeout)
if (0 == strlen(response)) {
continue;
}
break;
}
return n;
}
char offer[4096];
char answer[4096];
int main(int argc, char **argv) {
int n;
// create a new peer connection (no actual network communication yet)
urtc_peerconn_t *pc = urtc_peerconn_create(stun);
// TODO add tracks here
// get offer
n = longpoll(offer, sizeof(offer), "/offer");
fprintf(stderr, "%s\n", offer);
if (urtc_set_remote_description(pc, offer)) {
fprintf(stderr, "error: set remote description\n");
}
if (urtc_create_answer(pc, answer, sizeof(answer))) {
fprintf(stderr, "error: create answer\n");
}
http_post("demo.liburtc.org", "/answer", answer);
fprintf(stderr, "answer:\n%s\n", answer);
//urtc_set_local_description(pc, answer);
// block until signal
{
int signal;
sigset_t ss;
sigemptyset(&ss);
sigaddset(&ss, SIGINT);
sigaddset(&ss, SIGTERM);
sigaddset(&ss, SIGQUIT);
sigwait(&ss, &signal);
}
// clean up
urtc_peerconn_destroy(pc);
return 0;
}
/* vim: set expandtab ts=4 sw=4 tw=0 : */
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