// gcc testBipollar.c -lrdmacm -lpthread -o testBipollar

#include <stdlib.h>
#include <stdio.h>
#include <fcntl.h>
#include <arpa/inet.h>
#include <rdma/rsocket.h>
#include <errno.h>
#include <unistd.h>
#include <pthread.h>

// remove leading `r` to use regular TCP sockets
#define SOCKET rsocket
#define BIND rbind
#define LISTEN rlisten
#define ACCEPT raccept
#define GETSOCKNAME rgetsockname
#define CONNECT rconnect
#define POLL rpoll
#define FCNTL rfcntl

static const char* hostname = "10.0.2.15";  // << INSERT YOUR IP HERE
static int lrs, rs;

void *accepting_side_function(void *ptr);
void *polling_side_function(void *ptr);

int main() {
    int ret, port;
    pthread_t thread1, thread2;
    struct sockaddr_in addr, addr2;
    socklen_t addr_len = sizeof(addr);

    lrs = SOCKET(AF_INET, SOCK_STREAM, 0);
    if (lrs < 0)
        perror("rsocket; lrs");

    memset(&addr, 0, sizeof(addr));
    addr.sin_family = AF_INET;
    addr.sin_addr.s_addr = htonl(INADDR_ANY);
    addr.sin_port = htons(0);
    ret = BIND(lrs, (struct sockaddr *) &addr, addr_len);
    if (ret < 0)
        perror("rbind: lrs");

    ret = LISTEN(lrs, 10);
    if (ret < 0)
        perror("rlisten: lrs");

    memset(&addr, 0, sizeof(addr));
    if (GETSOCKNAME(lrs, (struct sockaddr *) &addr, &addr_len) < 0)
        perror("rgetsockname");
    port = addr.sin_port;
    fprintf(stdout, "\nlistening on port %d", ntohs(port));

    // Start the accepting-side thread
    pthread_create(&thread1, NULL, accepting_side_function, (void*) NULL);

    rs = SOCKET(AF_INET, SOCK_STREAM, 0);
    if (rs < 0)
        perror("rsocket: rs");

    // Configure the connecting socket to be non-blocking
    FCNTL(rs, F_SETFL, (FCNTL(rs, F_GETFL) | O_NONBLOCK));

    memset(&addr, 0, sizeof(addr));
    addr.sin_family = AF_INET;
    addr.sin_port = port;

    ret = inet_aton(hostname, &addr.sin_addr);
    if (ret < 0)
        perror("inet_aton");

    fprintf(stdout, "\nconnecting to %s:%d \n",
            inet_ntoa(addr.sin_addr), ntohs(addr.sin_port));
    ret = CONNECT(rs, (struct sockaddr *)&addr, sizeof(struct sockaddr));
    if (ret >= 0) {
        fprintf(stdout, "\nconnected immediately");
    } else if (errno == EAGAIN || errno == EWOULDBLOCK) {
        perror("rconnect: rs");
        exit(4);
    } else {
        fprintf(stdout, "\nconnect not completed, polling ...");
        pthread_create(&thread1, NULL, polling_side_function, (void*) NULL);
        pthread_create(&thread2, NULL, polling_side_function, (void*) NULL);

        pthread_join(thread1, NULL);
        pthread_join(thread2, NULL);
        fprintf(stdout, "\npolling threads completed");
    }
}

void *accepting_side_function(void *ptr) {
    struct sockaddr_in addr;
    socklen_t addr_len = sizeof(addr);
    int ret;

    fprintf(stdout, "\naccepted... ");
    ret = ACCEPT(lrs, (struct sockaddr *)&addr, &addr_len);
    if (ret >= 0) {
       fprintf(stdout, "\naccepted new connection: %d ", ret);
    } else {
        perror("raccept: lrs");
        exit(1);
    }
}

void *polling_side_function(void *ptr) {
    int ret;
    struct pollfd pfd;
    pfd.fd = rs;
    pfd.events = POLLOUT;

    fprintf(stdout, "\npolling: fd:[%d] ", pfd.fd);
    ret = POLL(&pfd, 1, -1);
    if (ret < 0) {
        perror("rpoll: rs");
        exit(7);
    }
    fprintf(stdout, "\npolling returned [%d]", ret);
}