gosl/net.c

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

// usleep support
#include <time.h>

#include "misc.h"

#define PORT(p) PORTSTR(p)
#define PORTSTR(p) #p

void *get_in_addr(struct sockaddr *sa)
{
    if (sa->sa_family == AF_INET) {
        return &(((struct sockaddr_in*)sa)->sin_addr);
    }

    return &(((struct sockaddr_in6*)sa)->sin6_addr);
}

int run_server(const struct prog_info *pinfo) {
	struct addrinfo hints, *servinfo, *p;
	int ret;
	int sockfd;

	char portbuf[6];
	memset(&hints, 0, sizeof(hints));
	hints.ai_family = AF_UNSPEC;
	hints.ai_socktype = SOCK_DGRAM;

	sprintf(portbuf, "%d", pinfo->port);
	if ((ret=getaddrinfo("0.0.0.0", portbuf, &hints, &servinfo)) != 0) {
		fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(ret));
	        return 1;
	}
// ...

	 for(p = servinfo; p != NULL; p = p->ai_next) {
	 	if ((sockfd = socket(p->ai_family, p->ai_socktype, p->ai_protocol)) == -1) {
	    	perror("talker: socket");
    	    continue;
        }
		break;
	}

	if (p == NULL) {
		fprintf(stderr, "talker: failed to bind socket\n");
		return 2;
	}

	struct timespec tim;
	tim.tv_sec = 0;
	tim.tv_nsec = 500000000;

	for (;;) {
		printf("sending...\n");
		int numbytes;
		if ((numbytes = sendto(sockfd, "bla", 3, 0, p->ai_addr, p->ai_addrlen)) == -1) {
			perror("error sending");
			return -44;
		}
		nanosleep(&tim, NULL);
	}

	freeaddrinfo(servinfo);

	close(sockfd);

	return 0;
}

int run_client(const struct prog_info *pinfo, void (*framecallback)(long) ) {

	struct addrinfo hints, *servinfo;
	char portbuf[6];

	//framecallback(123);

	memset(&hints, 0, sizeof(hints));
	hints.ai_family = AF_INET;      // IPv4
	hints.ai_socktype = SOCK_DGRAM; // UDP
	hints.ai_flags = AI_PASSIVE;

	sprintf(portbuf, "%d", pinfo->port);

	int rv;
	if ((rv = getaddrinfo(NULL, portbuf, &hints, &servinfo)) != 0) {
		fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(rv));
		return 1;
	}

	printf("got local address\n");
	
	struct addrinfo *info;
	int sockfd;
	char s[INET6_ADDRSTRLEN];
	for (info = servinfo; info != NULL; info = info->ai_next) {
/*		if (info->ai_addr) {
			struct sockaddr_in* p = (struct sockaddr_in *)info->ai_addr;
			inet_ntop(p->sin_family, &p->sin_addr, s, INET6_ADDRSTRLEN); 
			printf("  %d: %s\n", info->ai_addr->sa_family, s);
		}
*/

		if ((sockfd = socket(info->ai_family, info->ai_socktype, info->ai_protocol)) == -1) {
			perror("sock");
			continue; 
		}

		if (bind(sockfd, info->ai_addr, info->ai_addrlen) == -1) {
			perror("bind");
			continue; 
		}

		break;
	}
	if (!info) {
		fprintf(stderr, "unbound\n");
		return 2;
	}
	printf("check!\n");

	freeaddrinfo(servinfo); // free whole list
 
	struct sockaddr_storage their_addr;
	socklen_t addr_len = sizeof their_addr;
	int numbytes;
	char buf[10000];
	do {
		if ((numbytes = recvfrom(sockfd, buf, 9999 , 0, (struct sockaddr *)&their_addr, &addr_len)) == -1) {
	    	perror("recvfrom");
		    exit(1);
		}
		
		printf("listener: got packet from %s\n", inet_ntop(their_addr.ss_family, get_in_addr((struct sockaddr *)&their_addr), s, sizeof s));
		printf("listener: packet is %d bytes long\n", numbytes);
		buf[numbytes] = '\0';
		printf("listener: packet contains \"%s\"\n", buf);

		framecallback(123);

	} while (strncmp(buf, "exit", 10000));
	


	close(sockfd);
	
	return 0;
}