Function xs_tcp_read

modules/io/socket/lwip/tcp.c:298–373

}

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;
	}

	while (requested) {
		int use = requested;
		TCPBuffer buffer = tcp->buffers;
		struct pbuf *fragment = buffer->fragment;

		if (use > (fragment->len - buffer->fragmentOffset))
			use = fragment->len - buffer->fragmentOffset;

		c_memmove(out, buffer->fragmentOffset + (uint8_t *)fragment->payload, use);

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

		if (buffer->fragmentOffset == fragment->len) {
			buffer->fragment = fragment->next;