#include "llcomm.h"

#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <string.h>
#include <netdb.h>

Ll_comm::Ll_comm(Ll_comm_config const& cfg)
	:f_sd(-1)
{
	memset(&f_adr, 0, sizeof(f_adr));
	f_adr.sin_family = AF_INET;
	f_adr.sin_port=htons(cfg.port);
	if(cfg.server){
		f_adr.sin_addr.s_addr = INADDR_ANY;
		f_sd = socket(PF_INET, SOCK_DGRAM, 0);
		if(f_sd==-1){
			perror("socket()");
			exit(1);
		}
		if(-1==bind(f_sd, (struct sockaddr*)&f_adr, sizeof(f_adr))){
			perror("bind()");
			close(f_sd);
			exit(1);
		}
	} else {
		f_sd=socket(PF_INET, SOCK_DGRAM, 0);

		struct hostent* hh = gethostbyname(cfg.host);
		if(hh==0){
			int xx = h_errno;
			perror("gethostbyname()");
			fprintf(stderr, "%d\n", xx);
			close(f_sd);
			exit(1);
		}
		memcpy(&f_adr.sin_addr, hh->h_addr_list[0], 
			sizeof(f_adr.sin_addr));
		f_sd = socket(PF_INET, SOCK_DGRAM, 0);
		if(f_sd==-1){
			perror("socket()");
			exit(1);
		}
	}
}

Ll_comm::~Ll_comm()
{
	close(f_sd);
}

void 
Ll_comm::send_pack(void const* buf, int count)
{
	if( (rand() & 1) != 0){
		sendto(f_sd, buf, count, 0, (struct sockaddr*)&f_adr, 
			sizeof(f_adr));
	}
}

int 
Ll_comm::recv_pack(void* buf, int count, int timeout)
{
	int r;
	socklen_t len;
	fd_set set_r;
	fd_set set_w;
	fd_set set_s;
	struct timeval time;
	int fd_max = f_sd+1;
	FD_ZERO(&set_r);
	FD_SET(f_sd, &set_r);
	FD_ZERO(&set_w);
	FD_ZERO(&set_s);
	time.tv_usec = (timeout % 1000)*1000;
	time.tv_sec = timeout/1000;
	r = select(fd_max, &set_r, &set_w, &set_s, &time);
	if(r<0){
		perror("select()");
		exit(1);
	}
	if(r==0){
		return -1;
	}
	
	len = sizeof(f_adr);
	r = recvfrom(f_sd, buf, count, 0, (struct sockaddr*)&f_adr, &len);
	if(r<0){
		perror("recvfrom()");
		exit(1);
	}
	return r;
}