#include <stdlib.h>
#include <stdio.h>
#include <time.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <sys/wait.h>
#include <errno.h>
#include <signal.h>
#include <string.h>
#include <sys/socket.h>
#include <netdb.h>
#include <netinet/in.h>
#include <arpa/inet.h>

//server tcp dzialajacy interacyjnie pod adres lokalhost port > 1024
//klient program rc serwer wysyla w formie tekstowej znaczniki czasu takie jakie istnieja

#define PORT 8080
#define SA const struct sockaddr

void errorExit(const char* str)
{
	perror(str);
	exit(EXIT_FAILURE);
}

int sockfd, len, n;
struct sockaddr_in servaddr, cliaddr;

void func()
{
	int SIZE = 256;
	char buff[SIZE];

	len = sizeof(cliaddr);

	while(1)
	{
		memset(&buff,'\0',sizeof(buff));
		n = recvfrom(sockfd, (char*)buff, SIZE, MSG_WAITALL, (struct sockaddr*) &cliaddr, (socklen_t*)&len);

		buff[n] = '\0';
		printf("%s\n", buff);

		sendto(sockfd, "siema", 5, MSG_CONFIRM, (const struct sockaddr*)&cliaddr, len);
	}
}

int main( int argc, char* argv[] )
{
	if((sockfd=socket(AF_INET, SOCK_DGRAM, 0))==-1)
		errorExit("socket");

	memset(&servaddr,'\0', sizeof(servaddr));
	memset(&cliaddr,'\0', sizeof(cliaddr));

	servaddr.sin_family = AF_INET;
	servaddr.sin_addr.s_addr = inet_addr("127.0.0.1");
	servaddr.sin_port=htons(PORT);

	if(bind(sockfd, (SA*)&servaddr, sizeof(servaddr))!=0)
		errorExit("bind");

	func();

	if(close(sockfd)==-1)
		errorExit("close");

	exit(EXIT_SUCCESS);
}