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

#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>

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

void *connecting_side_function(void *ptr) {
    int rs, ret;
    struct sockaddr_in addr;

    rs = rsocket(AF_INET, SOCK_STREAM, 0);
    if (rs < 0)
        perror("rsocket connecting-side");

    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 = rconnect(rs, (struct sockaddr *)&addr, sizeof(struct sockaddr));
    if (ret < 0) {
        perror("rconnect");
        exit(3);
    }
    fprintf(stdout, "\nconnected");

    usleep(100000);  // just wait
}

int main() {
    int rs1, rs2, ret;
    pthread_t thread;
    char buffer[256];
    struct sockaddr_in addr, addr2;
    socklen_t addr_len = sizeof(addr);

    rs1 = rsocket(AF_INET, SOCK_STREAM, 0);
    if (rs1 < 0)
        perror("rsocket");

    memset(&addr, 0, sizeof(addr));
    addr.sin_family = AF_INET;
    addr.sin_addr.s_addr = htonl(INADDR_ANY);
    addr.sin_port = htons(0);
    ret = rbind(rs1, (struct sockaddr *) &addr, addr_len);
    if (ret < 0)
        perror("rbind");

    ret = rlisten(rs1, 10); 
    if (ret < 0)
        perror("rlisten");

    memset(&addr, 0, sizeof(addr));
    if (rgetsockname(rs1, (struct sockaddr *) &addr, &addr_len) < 0)
        perror("rgetsockname");
    port = addr.sin_port;
    fprintf(stdout, "\nlistening on port %d", ntohs(port));

    // Configure the listening socket to be non-blocking
    rfcntl(rs1, F_SETFL, (rfcntl(rs2, F_GETFL) | O_NONBLOCK));

    // Start the connecting thread
    pthread_create(&thread, NULL, connecting_side_function, (void*) NULL);

    while (1) {
        rs2 = raccept(rs1, (struct sockaddr *)&addr2, &addr_len);
        if (rs2 >= 0) {
           fprintf(stdout, "\naccepted rs2: %d ", rs2);
           break;
        } else if (rs2 < 0 && !(errno == EAGAIN || errno == EWOULDBLOCK)) {
            perror("raccept");
            exit(1);
        }
        usleep(50*100);
    }

    // Configure the accepted socket to be blocking
    rfcntl(rs1, F_SETFL, (rfcntl(rs2, F_GETFL) & ~O_NONBLOCK));
    
    //usleep(10*100);  // if you wait a little all is ok!!!

    fprintf(stdout, "\nreading ..."); 
    fflush(stdout);
    ret = rread(rs2, buffer, 255);
    if (ret < 0) {
        fprintf(stdout, "\nrread returned: %d, errno: %d ", ret, errno);
        perror("rread");
    } else {
        fprintf(stdout, "\nrread returned: %d ", ret); 
    }
}