/**
* Sends datagram to the given address using the given socket.
*
* @param env JNIEnv interface.
* @param obj object instance.
* @param sd socket descriptor.
* @param address remote address.
* @param buffer data buffer.
* @param bufferSize buffer size.
* @return sent size.
* @throws IOException
*/
static ssize_t SendDatagramToSocket(
JNIEnv* env,
jobject obj,
int sd,
const struct sockaddr_in* address,
const char* buffer,
size_t bufferSize)
{
// Send data buffer to the socket
LogAddress(env, obj, "Sending to", address);
ssize_t sentSize = sendto(sd, buffer, bufferSize, 0,
(const sockaddr*) address,
sizeof(struct sockaddr_in));
// If send is failed
if (-1 == sentSize)
{
// Throw an exception with error number
ThrowErrnoException(env, "java/io/IOException", errno);
}
else if (sentSize > 0)
{
LogMessage(env, obj, "Sent %d bytes: %s", sentSize, buffer);
}
return sentSize;
}
/**
* Blocks and waits for incoming client connections on the
* given socket.
*
* @param env JNIEnv interface.
* @param obj object instance.
* @param sd socket descriptor.
* @return client socket.
* @throws IOException
*/
static int AcceptOnSocket(
JNIEnv* env,
jobject obj,
int sd)
{
struct sockaddr_in address;
socklen_t addressLength = sizeof(address);
// Blocks and waits for an incoming client connection
// and accepts it
//LogMessage(env, obj, "Waiting for a client connection...");
int clientSocket = accept(sd, (struct sockaddr*) &address, &addressLength);
// If client socket is not valid
if (-1 == clientSocket)
{
// Throw an exception with error number
ThrowErrnoException(env, "java/io/IOException", errno);
}
else
{
// Log address
LogAddress(env, obj, "Client connection from ", &address);
}
return clientSocket;
}
// receive datagram from udp socket
static ssize_t ReceiveDatagramFromSocket(
JNIEnv* env,
jobject obj,
int sd,
struct sockaddr_in* address,
char* buffer,
size_t bufferSize)
{
socklen_t addressLength = sizeof(struct sockaddr_in);
// Receive datagram from socket
LogMessage(env, obj, "Receiving datagram from the socket...");
ssize_t recvSize = recvfrom(sd, buffer, bufferSize, 0,
(struct sockaddr*) address,
&addressLength);
// If receive is failed
if (-1 == recvSize)
{
// Throw an exception with error number
ThrowErrnoException(env, "java/io/IOException", errno);
}
else
{
// Log address
LogAddress(env, obj, "Received datagram from", address);
// NULL terminate the buffer to make it a string
buffer[recvSize] = 0;
// If data is received
if (recvSize > 0)
{
LogMessage(env, obj, "Received %d bytes: %s",
recvSize, buffer);
}
}
return recvSize;
}
