Rename and refactor. Proper port binding.

set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/bin)

add_subdirectory(prrt)

add_library(PRRT prrt/prrt_socket.c)

add_library(PRRT prrt/socket.c)

add_executable(sender sender.c)

add_executable(receiver receiver.c)

//

// Created by root on 05.11.15.

//

#ifndef PRRT_DEFINES_H

#define PRRT_DEFINES_H

#endif //PRRT_DEFINES_H

#include <netdb.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <unistd.h>

#include <arpa/inet.h>

#include <netinet/in.h>

#include <sys/types.h>

#include <sys/socket.h>

#include "prrt_socket.h"

int prrt_socket() {

    int fd;

    if((fd = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {

        perror("cannot create socket");

        return -1;

    }

    return fd;

}

int prrt_connect() {

    return 0;

}

int prrt_bind(int fd, int port) {

    struct sockaddr_in address;

    memset((char*) &address, 0, sizeof(address));

    address.sin_family = AF_INET;

    address.sin_addr.s_addr = htonl(INADDR_ANY);

    address.sin_port = htons(port);

    return bind(fd, (struct sockaddr *) &address, sizeof(address));

}

int prrt_send(int fd, const void * data, size_t data_len) {

    // TODO: should iterate over receivers

    struct hostent *hp;

    char *host = "localhost";

    struct sockaddr_in targetaddr;

    memset((char*) &targetaddr, 0, sizeof(targetaddr));

    targetaddr.sin_family = AF_INET;

    targetaddr.sin_port = htons(5000);  // TODO: make port flexible

    hp = gethostbyname(host);

    memcpy((void *)&targetaddr.sin_addr, hp->h_addr_list[0], hp->h_length);

    if((sendto(fd, data, data_len, 0, (struct sockaddr *) &targetaddr, sizeof(targetaddr)) < 0)) {

        perror("sendto failed");

        return -1;

    }

    return 0;

}

int prrt_recv(int fd, void * bufin, size_t length) {

    int n;

    struct sockaddr_in remote;

    socklen_t addrlen = sizeof(remote);

    n = recvfrom(fd, bufin,length, 0, (struct sockaddr *) &remote, &addrlen);

    printf("got a datagram from %s port %d\n", inet_ntoa(remote.sin_addr), ntohs(remote.sin_port));

    return n;

}

int prrt_close(int fd) {

    close(fd);

    return 0;

}

#ifndef PRRT_SOCKET

#define PRRT_SOCKET

int prrt_socket(void);

int prrt_close(int fd);

int prrt_bind(int fd, int port);

int prrt_connect();

int prrt_send(int fd, const void * data, size_t data_len);

int prrt_recv(int fd, void * bufin, size_t length);

#endif

#include <netdb.h>

#include <stdio.h>

#include <string.h>

#include <unistd.h>

#include <arpa/inet.h>

#include "socket.h"

int prrt_create_socket(prrt_socket *sock, uint16_t port) {

    // Create Data Socket

    if((sock->fd_data = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {

        perror("cannot create socket");

        return -1;

    }

    // Bind Data Socket

    struct sockaddr_in address;

    memset((char*) &address, 0, sizeof(address));

    address.sin_family = AF_INET;

    address.sin_addr.s_addr = htonl(INADDR_ANY);

    address.sin_port = htons(port);

    if(bind(sock->fd_data, (struct sockaddr *) &address, sizeof(address)) < 0) {

        perror("cannot bind socket");

        return -1;

    }

    // Create Feedback Socket

    if((sock->fd_feedback = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {

        perror("cannot create socket");

        return -1;

    }

    // Bind Feedback Socket

    memset((char*) &address, 0, sizeof(address));

    address.sin_family = AF_INET;

    address.sin_addr.s_addr = htonl(INADDR_ANY);

    address.sin_port = htons((uint16_t) (port + 1)); // TODO: fail if port is 65535

    if(bind(sock->fd_feedback, (struct sockaddr *) &address, sizeof(address)) < 0) {

        perror("cannot bind socket");

        return -1;

    }

    return 0;

}

int prrt_connect(prrt_socket *sock, char *host, size_t host_len, uint16_t port) {

    return 0;

}

int prrt_send(prrt_socket *sock, const void *data, size_t data_len) {

    // TODO: should iterate over receivers

    struct hostent *hp;

    char *host = "localhost"; // TODO make receiver flexible

    struct sockaddr_in targetaddr;

    memset((char*) &targetaddr, 0, sizeof(targetaddr));

    targetaddr.sin_family = AF_INET;

    targetaddr.sin_port = htons(5000);  // TODO: make port flexible

    hp = gethostbyname(host);

    memcpy((void *)&targetaddr.sin_addr, hp->h_addr_list[0], hp->h_length);

    if((sendto(sock->fd_data, data, data_len, 0, (struct sockaddr *) &targetaddr, sizeof(targetaddr)) < 0)) {

        perror("sendto failed");

        return -1;

    }

    return 0;

}

ssize_t prrt_recv(prrt_socket *sock, void *bufin, size_t length) {

    // RECEIVE DATA

    ssize_t n;

    struct sockaddr_in remote;

    socklen_t addrlen = sizeof(remote);

    n = recvfrom(sock->fd_data, bufin, length, 0, (struct sockaddr *) &remote, &addrlen);

    uint16_t remote_port = ntohs(remote.sin_port);

    char *remote_host = inet_ntoa(remote.sin_addr);

    printf("got a datagram from %s port %d\n", remote_host, remote_port);

    // REPLY

    struct sockaddr_in targetaddr;

    memset((char*) &targetaddr, 0, sizeof(targetaddr));

    targetaddr.sin_family = AF_INET;

    targetaddr.sin_port = htons(remote_port + 1);

    struct hostent *hp;

    hp = gethostbyname(remote_host);

    memcpy((void *)&targetaddr.sin_addr, hp->h_addr_list[0], hp->h_length);

    if((sendto(sock->fd_data, bufin, n, 0, (struct sockaddr *) &targetaddr, sizeof(targetaddr)) < 0)) {

        perror("sendto failed");

        return -1;

    }

    return n;

}

int prrt_close_socket(prrt_socket *sock) {

    close(sock->fd_data);

    close(sock->fd_feedback);

    return 0;

}

ssize_t prrt_recv_feedback(prrt_socket *sock, void *bufin, size_t length) {

    printf("RECEIVING FB");

    ssize_t n;

    struct sockaddr_in remote;

    socklen_t addrlen = sizeof(remote);

    n = recvfrom(sock->fd_feedback, bufin, length, 0, (struct sockaddr *) &remote, &addrlen);

    uint16_t remote_port = ntohs(remote.sin_port);

    char *remote_host = inet_ntoa(remote.sin_addr);

    printf("got feedback from %s port %d\n", remote_host, remote_port);

    return n;

}