/**
* Invoked prior to write to prepare the WSABUF array. Where necessary, it substitutes
* non-direct buffers with direct buffers.
*/
void prepareBuffers() {
shadow = new ByteBuffer[numBufs];
long address = writeBufferArray;
for (int i = 0; i < numBufs; i++) {
ByteBuffer src = bufs[i];
int pos = src.position();
int lim = src.limit();
assert (pos <= lim);
int rem = (pos <= lim ? lim - pos : 0);
long a;
if (!(src instanceof DirectBuffer)) {
// substitute with direct buffer
ByteBuffer bb = Util.getTemporaryDirectBuffer(rem);
bb.put(src);
bb.flip();
src.position(pos); // leave heap buffer untouched for now
shadow[i] = bb;
a = ((DirectBuffer) bb).address();
} else {
shadow[i] = src;
a = ((DirectBuffer) src).address() + pos;
}
unsafe.putAddress(address + OFFSETOF_BUF, a);
unsafe.putInt(address + OFFSETOF_LEN, rem);
address += SIZEOF_WSABUF;
}
}
/**
* Invoked prior to read to prepare the WSABUF array. Where necessary, it substitutes non-direct
* buffers with direct buffers.
*/
void prepareBuffers() {
shadow = new ByteBuffer[numBufs];
long address = readBufferArray;
for (int i = 0; i < numBufs; i++) {
ByteBuffer dst = bufs[i];
int pos = dst.position();
int lim = dst.limit();
assert (pos <= lim);
int rem = (pos <= lim ? lim - pos : 0);
long a;
if (!(dst instanceof DirectBuffer)) {
// substitute with direct buffer
ByteBuffer bb = Util.getTemporaryDirectBuffer(rem);
shadow[i] = bb;
a = ((DirectBuffer) bb).address();
} else {
shadow[i] = dst;
a = ((DirectBuffer) dst).address() + pos;
}
unsafe.putAddress(address + OFFSETOF_BUF, a);
unsafe.putInt(address + OFFSETOF_LEN, rem);
address += SIZEOF_WSABUF;
}
}