OpenTTCN/Developer corner/Creating adapter with OpenTTCN SDK for CPP/Utilities.cpp

From OpenTTCN

#include "Utilities.h"

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <errno.h>
#include <sys/types.h>
#include <assert.h>
#include <ctype.h>
#include <malloc.h>

#ifndef _WIN32
#include <netinet/in.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#else
#include <winsock2.h>
typedef int socklen_t;
#endif

int _socketDesc = 0;
int _socketDescInitialized = 0;

/* Returns 0 on success, non-zero on error. */
int bindSocketToAnyPort(int* dstSocketDesc)
{
    int rval = 0;
    int errorCode = 0;
    static struct sockaddr_in myaddr;

    *dstSocketDesc = (int) socket(PF_INET, SOCK_DGRAM, 0);

    memset (&myaddr, 0, sizeof myaddr);
    myaddr.sin_addr.s_addr = htonl(INADDR_ANY);

#ifdef _WIN32
    myaddr.sin_family = AF_INET;
#endif

    myaddr.sin_port = htons(0); /* pick any available port */
    rval = bind(*dstSocketDesc, (struct sockaddr *) &myaddr, sizeof myaddr);

    if (rval < 0)
    {

#ifndef _WIN32
        printf("bindSocketToAnyPort(): "
            "Error: bind() returned: %s\n", strerror(errno));
#else
        int errorCode = WSAGetLastError();

        printf("bindSocketToAnyPort(): "
            "Error: bind() returned error code %i\n", errorCode);
#endif

        return 1;
    }

    return 0;
}

int sendDatagramPacket(unsigned long host_,
    unsigned short port_, const char* data_, long length_)
{
    int rval = 0;
    int errorCode = 0;

    struct sockaddr_in saddr;
    memset (&saddr, 0, sizeof saddr);

    if (!_socketDescInitialized)
    {
        rval = bindSocketToAnyPort(&_socketDesc);

        if (rval)
        {
            printf("sendDatagramPacket(): Cannot bind socket.\n");
            return 1;
        }

        _socketDescInitialized = 1;
    }

    saddr.sin_family = AF_INET;

    saddr.sin_addr.s_addr = host_;
    saddr.sin_port = port_;

    while (1)
    {
        rval = sendto(
            _socketDesc, 
            data_, 
            length_, 
            0,
            (struct sockaddr *) &saddr, 
            sizeof saddr);

        if ((-1 == rval) && ((errno == EAGAIN) || (errno == EINTR)))
        {
            /* resending */
        }
        else if (-1 == rval)
        {
            printf("sendDatagramPacket(): Cannot send frame.\n");

#ifndef _WIN32
            printf("sendDatagramPacket(): send error = %s\n", strerror(errno));
#else
            errorCode = WSAGetLastError();
            printf("sendDatagramPacket(): send error code = %i\n", errorCode);
#endif
            return 1;
        }
        else
        {
            /* send operation succeeded */
            break;
        }
    }

    return 0;
}