/* tcp.c
* By Ron
* Created August, 2008
*
* (See LICENSE.md)
*/
#include <stdio.h>
#include <string.h>
#ifdef WIN32
#include <winsock2.h>
#else
#include <errno.h>
#include <fcntl.h>
#include <netdb.h>
#include <unistd.h>
#include <arpa/inet.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <sys/types.h>
#endif
#include "tcp.h"
void winsock_initialize()
{
#ifdef WIN32
WORD wVersionRequested = MAKEWORD(2, 2);
WSADATA wsaData;
int error = WSAStartup(wVersionRequested, &wsaData);
switch(error)
{
case WSASYSNOTREADY:
fprintf(stderr, "The underlying network subsystem is not ready for network communication.\n");
exit(1);
break;
case WSAVERNOTSUPPORTED:
fprintf(stderr, "The version of Windows Sockets support requested is not provided by this particular Windows Sockets implementation.\n");
exit(1);
break;
case WSAEINPROGRESS:
fprintf(stderr, "A blocking Windows Sockets 1.1 operation is in progress.\n");
exit(1);
break;
case WSAEPROCLIM:
fprintf(stderr, "A limit on the number of tasks supported by the Windows Sockets implementation has been reached.\n");
exit(1);
break;
case WSAEFAULT:
fprintf(stderr, "The lpWSAData parameter is not a valid pointer.\n");
exit(1);
break;
}
#endif
}
int tcp_connect_options(char *host, uint16_t port, int non_blocking)
{
struct sockaddr_in serv_addr;
struct hostent *server;
int s;
int status;
/* Create the socket */
s = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);
if (s == -1)
nbdie("tcp: couldn't create socket");
if(non_blocking)
{
#ifdef WIN32
unsigned long mode = 1;
ioctlsocket(s, FIONBIO, &mode);
#else
int flags = fcntl(s, F_GETFL, 0);
flags = flags | O_NONBLOCK;
fcntl(s, F_SETFL, flags);
#endif
}
/* Look up the host */
server = gethostbyname(host);
if(!server)
{
fprintf(stderr, "Couldn't find host %s\n", host);
return -1;
}
/* Set up the server address */
memset(&serv_addr, '\0', sizeof(serv_addr));
serv_addr.sin_family = AF_INET;
serv_addr.sin_port = htons(port);
memcpy(&serv_addr.sin_addr, server->h_addr_list[0], server->h_length);
/* Connect */
status = connect(s, (struct sockaddr*)&serv_addr, sizeof(serv_addr));
#ifdef WIN32
if(status < 0 && GetLastError() != WSAEWOULDBLOCK)
#else
if(status < 0 && errno != EINPROGRESS)
#endif
{
nberror("tcp: couldn't connect to host");
return -1;
}
return s;
}
int tcp_connect(char *host, uint16_t port)
{
return tcp_connect_options(host, port, 0);
}
void tcp_set_nonblocking(int s)
{
#ifdef WIN32
/* TODO: This */
fprintf(stderr, "Don't know how to do nonblocking on Windows\n");
exit(1);
#else
fcntl(s, F_SETFL, O_NONBLOCK);
#endif
}
int tcp_listen(char *address, uint16_t port)
{
int s;
struct sockaddr_in serv_addr;
/* Get the server address */
memset((char *) &serv_addr, '\0', sizeof(serv_addr));
serv_addr.sin_family = AF_INET;
serv_addr.sin_addr.s_addr = inet_addr(address);
serv_addr.sin_port = htons(port);
if(serv_addr.sin_addr.s_addr == INADDR_NONE)
nbdie("tcp: couldn't parse local address");
/* Create a socket */
s = socket(AF_INET, SOCK_STREAM, 0);
if(s < 0)
{
nbdie("tcp: couldn't create socket");
}
else
{
/* Bind the socket */
if (bind(s, (struct sockaddr *) &serv_addr, sizeof(serv_addr)) < 0)
nbdie("tcp: couldn't bind to socket");
/* Switch the socket to listen mode. TODO: why 20? */
if(listen(s, 20) < 0)
nbdie("tcp: couldn't listen on socket");
}
return s;
}
int tcp_accept(int listen, char **address, uint16_t *port)
{
struct sockaddr_in addr;
socklen_t sockaddr_len = sizeof(struct sockaddr_in);
int s;
s = accept(listen, (struct sockaddr *) &addr, &sockaddr_len);
if(s < 0)
nbdie("tcp: couldn't accept connection");
*address = inet_ntoa(addr.sin_addr);
*port = ntohs(addr.sin_port);
return s;
}
ssize_t tcp_send(int s, void *data, size_t length)
{
return send(s, data, length, 0);
}
ssize_t tcp_recv(int s, void *buffer, size_t buffer_length)
{
return recv(s, buffer, buffer_length, 0);
}
int tcp_close(int s)
{
#ifdef WIN32
return closesocket(s);
#else
return close(s);
#endif
}
#if 0
int main(int argc, char *argv[])
{
char buffer[1024];
int s;
int listener;
struct sockaddr_in addr;
int port;
size_t len;
memset(buffer, 0, 1024);
winsock_initialize();
s = tcp_connect("www.google.ca", 80);
if(s < 0)
DIE("Fail");
tcp_send(s, "GET / HTTP/1.0\r\nHost: www.google.com\r\n\r\n", 41);
tcp_recv(s, buffer, 1024);
tcp_close(s);
printf("%s\n", buffer);
printf("Listening on TCP/6666\n");
listener = tcp_listen("0.0.0.0", 6666);
s = tcp_accept(listener, &addr, &port);
if(s < 0)
DIE("Fail");
printf("Connection accepted from %s:%d\n", inet_ntoa(addr.sin_addr), ntohs(addr.sin_port));
memset(buffer, 0, 1024);
strcpy(buffer, "HELLO!");
len = 7;
while(len > 0 && tcp_send(s, buffer, len) >= 0)
{
memset(buffer, 0, 1024);
len = tcp_recv(s, buffer, 1024);
printf("Received: %s [%d]\n", buffer, len);
}
printf("%s\n", buffer);
return 1;
}
#endif