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#include <arpa/inet.h>
#include <errno.h>
#include <netdb.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include "tcp.h"
int tcp_connect(const char* const host, const int port)
{
char ip[INET6_ADDRSTRLEN];
hostname_to_ip(host , ip);
printf("%s resolved to %s\n" , host, ip);
struct sockaddr_in sa;
int sd = socket(AF_INET, SOCK_STREAM, 0);
memset(&sa, '\0', sizeof(sa));
sa.sin_family = AF_INET;
sa.sin_port = htons(port);
inet_pton(AF_INET, ip, &sa.sin_addr);
int err = connect(sd, (struct sockaddr *) &sa, sizeof(sa));
if (err < 0) {
fprintf(stderr, "Couldn't connect %s:%d : %s\n", host, port, strerror(errno));
return -1;
}
return sd;
}
void tcp_close(const int sd)
{
shutdown(sd, SHUT_RDWR);
close(sd);
}
int hostname_to_ip(const char* const hostname, char *ip)
{
struct addrinfo hints, *servinfo; //, *p;
struct sockaddr_in *h;
int rv, ret = 0;
memset(&hints, 0, sizeof hints);
hints.ai_family = AF_UNSPEC; // use AF_INET6 to force IPv6
hints.ai_socktype = SOCK_STREAM;
if ( (rv = getaddrinfo( hostname , "http" , &hints , &servinfo)) != 0)
{
fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(rv));
ret = 1;
} else {
//// loop through all the results and connect to the first we can
//for(p = servinfo; p != NULL; p = p->ai_next)
//{
// h = (struct sockaddr_in *) p->ai_addr;
// strcpy(ip , inet_ntoa( h->sin_addr ) );
//}
h = (struct sockaddr_in *) servinfo->ai_addr;
strcpy(ip, inet_ntoa(h->sin_addr));
}
freeaddrinfo(servinfo); // all done with this structure
return ret;
}
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