Function xs_tcp_read

modules/io/socket/zephyr/tcp.c:303–374

}

void xs_tcp_read(xsMachine *the)
{
	TCP tcp = xsmcGetHostDataValidate(xsThis, (void *)&xsTCPHooks);
	TCPBuffer buffer;
	int requested;
	uint8_t *out, value;

	if (!tcp->buffers)
		return;

	if (kIOFormatBuffer == tcp->format) {
		int available = 0;
		uint8_t allocate = 1;
		xsUnsignedValue byteLength;

		for (buffer = tcp->buffers; NULL != buffer; buffer = buffer->next)
			available += buffer->bytes;

		if (0 == xsmcArgc)
			requested = available;
		else if (xsReferenceType == xsmcTypeOf(xsArg(0))) {
			xsResult = xsArg(0);
			xsmcGetBufferWritable(xsResult, (void **)&out, &byteLength);
			requested = (int)byteLength;
			allocate = 0;
			xsmcSetInteger(xsResult, requested);
		}
		else
			requested = xsmcToInteger(xsArg(0));

		if ((requested <= 0) || (requested > available)) 
			xsUnknownError("invalid");

		if (allocate)
			out = xsmcSetArrayBuffer(xsResult, NULL, requested);
	}
	else {
		requested = 1;
		out = &value;
	}

	//@@ not sure we need a loop... that was mostly about lwip fragments
	while (requested) {
		int use = requested;
		TCPBuffer buffer = tcp->buffers;

		if (use > buffer->bytes)
			use = buffer->bytes;

		if (0 != net_pkt_read(buffer->pkt, out, use))
			xsUnknownError("net_pkt_read failed");

		out += use;
		requested -= use;
		buffer->bytes -= use;

		if (0 == buffer->bytes) {
			tcp->buffers = buffer->next;