Function _xsmcGetBuffer

xs/sources/xsmc.c:282–336

}

txInteger _xsmcGetBuffer(txMachine *the, txSlot *slot, void **data, txUnsigned *count, txBoolean writable)
{
	txSlot* instance;

	if (slot->kind != XS_REFERENCE_KIND)
		goto bail;

	instance = slot->value.reference;
	if (!(((slot = instance->next)) && (slot->flag & XS_INTERNAL_FLAG)))
		goto bail;

	if (slot->kind == XS_ARRAY_BUFFER_KIND) {
		txSlot* bufferInfo = slot->next;
		if (slot->value.arrayBuffer.address == C_NULL)
			mxTypeError("detached buffer");
		if (writable && (slot->flag & XS_DONT_SET_FLAG))
			mxTypeError("read-only buffer");
		*data = slot->value.arrayBuffer.address;
		*count = bufferInfo->value.bufferInfo.length;
		return xsBufferRelocatable;
	}

	if (slot->kind == XS_TYPED_ARRAY_KIND) {
		txSlot* view = slot->next;
		txSlot* buffer = view->next;
		if (1 != slot->value.typedArray.dispatch->size)
			goto bail;
		return _xsmcGetViewBuffer(the, view, buffer, data, count, writable);
	}
	
	if (slot->kind == XS_HOST_KIND) {
		txSlot* bufferInfo = slot->next;
		if (slot->flag & XS_HOST_CHUNK_FLAG)
			goto bail;
		if (writable && (slot->flag & XS_DONT_SET_FLAG))
			mxTypeError("read-only buffer");
		if (bufferInfo && (bufferInfo->kind == XS_BUFFER_INFO_KIND)) {
			*data = (uint8_t *)slot->value.host.data;
			*count = bufferInfo->value.bufferInfo.length;
		}
		else
			mxTypeError("not host buffer");		// Use xsmcSetHostBuffer instead of xsmcSetHostData
		return xsBufferNonrelocatable;
	}

	if (slot->kind == XS_DATA_VIEW_KIND) {
		txSlot* view = slot;
		txSlot* buffer = view->next;
		return _xsmcGetViewBuffer(the, view, buffer, data, count, writable);
	}

bail:
	mxTypeError("invalid buffer");
	return xsBufferNonrelocatable;
}