mirror of
https://github.com/CHOMPStation2/CHOMPStation2.git
synced 2025-12-11 18:53:06 +00:00
49890421f8
This allows for more secure and stable transmission on Linux, but you might see some improvements on Windows too. Code lies in (confusingly) lib/src. nudge.c should be compiled to lib/nudge.[dll/so] and be linked against netutil.c. There's some horribly hacky code in nudge.c to assemble pickled data, but it's probably the fastest way that's still safe. Signed-off-by: Mloc-Argent <colmohici@gmail.com>
134 lines
3.3 KiB
C++
134 lines
3.3 KiB
C++
// OS-specific networking includes
|
|
// -------------------------------
|
|
#ifdef __WIN32
|
|
#include <winsock2.h>
|
|
typedef int socklen_t;
|
|
#else
|
|
extern "C" {
|
|
#include <sys/types.h>
|
|
#include <sys/socket.h>
|
|
#include <netinet/in.h>
|
|
#include <arpa/inet.h>
|
|
#include <netdb.h>
|
|
#include <fcntl.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
}
|
|
|
|
typedef int SOCKET;
|
|
typedef sockaddr_in SOCKADDR_IN;
|
|
typedef sockaddr SOCKADDR;
|
|
#define SOCKET_ERROR -1
|
|
#endif
|
|
|
|
// Socket used for all communications
|
|
SOCKET sock;
|
|
|
|
// Address of the remote server
|
|
SOCKADDR_IN addr;
|
|
|
|
// Buffer used to return dynamic strings to the caller
|
|
#define BUFFER_SIZE 1024
|
|
char return_buffer[BUFFER_SIZE];
|
|
|
|
// exposed functions
|
|
// ------------------------------
|
|
|
|
const char* SUCCESS = "1\0"; // string representing success
|
|
|
|
#ifdef __WIN32
|
|
#define DLL_EXPORT __declspec(dllexport)
|
|
#else
|
|
#define DLL_EXPORT __attribute__ ((visibility ("default")))
|
|
#endif
|
|
|
|
// arg1: ip(in the xx.xx.xx.xx format)
|
|
// arg2: port(a short)
|
|
// return: NULL on failure, SUCCESS otherwise
|
|
extern "C" DLL_EXPORT const char* establish_connection(int n, char *v[])
|
|
{
|
|
// extract args
|
|
// ------------
|
|
if(n < 2) return 0;
|
|
const char* ip = v[0];
|
|
const char* port_s = v[1];
|
|
unsigned short port = atoi(port_s);
|
|
|
|
// set up network stuff
|
|
// --------------------
|
|
#ifdef __WIN32
|
|
WSADATA wsa;
|
|
WSAStartup(MAKEWORD(2,0),&wsa);
|
|
#endif
|
|
sock = socket(AF_INET,SOCK_DGRAM,0);
|
|
|
|
// make the socket non-blocking
|
|
// ----------------------------
|
|
#ifdef __WIN32
|
|
unsigned long iMode=1;
|
|
ioctlsocket(sock,FIONBIO,&iMode);
|
|
#else
|
|
fcntl(sock, F_SETFL, O_NONBLOCK);
|
|
#endif
|
|
|
|
// establish a connection to the server
|
|
// ------------------------------------
|
|
memset(&addr,0,sizeof(SOCKADDR_IN));
|
|
addr.sin_family=AF_INET;
|
|
addr.sin_port=htons(port);
|
|
|
|
// convert the string representation of the ip to a byte representation
|
|
addr.sin_addr.s_addr=inet_addr(ip);
|
|
|
|
return SUCCESS;
|
|
}
|
|
|
|
// arg1: string message to send
|
|
// return: NULL on failure, SUCCESS otherwise
|
|
extern "C" DLL_EXPORT const char* send_message(int n, char *v[])
|
|
{
|
|
// extract the args
|
|
if(n < 1) return 0;
|
|
const char* msg = v[0];
|
|
|
|
// send the message
|
|
int rc = sendto(sock,msg,strlen(msg),0,(SOCKADDR*)&addr,sizeof(SOCKADDR));
|
|
|
|
// check for errors
|
|
if (rc != -1) {
|
|
return SUCCESS;
|
|
}
|
|
else {
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
// no args
|
|
// return: message if any received, NULL otherwise
|
|
extern "C" DLL_EXPORT const char* recv_message(int n, char *v[])
|
|
{
|
|
SOCKADDR_IN sender; // we will store the sender address here
|
|
|
|
socklen_t sender_byte_length = sizeof(sender);
|
|
|
|
// Try receiving messages until we receive one that's valid, or there are no more messages
|
|
while(1) {
|
|
int rc = recvfrom(sock, return_buffer, BUFFER_SIZE,0,(SOCKADDR*) &sender,&sender_byte_length);
|
|
if(rc > 0) {
|
|
// we could read something
|
|
|
|
if(sender.sin_addr.s_addr != addr.sin_addr.s_addr) {
|
|
continue; // not our connection, ignore and try again
|
|
} else {
|
|
return_buffer[rc] = 0; // 0-terminate the string
|
|
return return_buffer;
|
|
}
|
|
}
|
|
else {
|
|
break; // no more messages, stop trying to receive
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|