Heavy optimizations for ROM/RAM usage in UAVCAN_TINY mode

libuavcan/include/uavcan/node/generic_subscriber.hpp

@@ -98,11 +98,16 @@ class UAVCAN_EXPORT TransferListenerInstantiationHelper
     enum { DataTypeMaxByteLen = BitLenToByteLen<DataStruct_::MaxBitLen>::Result };
     enum { NeedsBuffer = int(DataTypeMaxByteLen) > int(MaxSingleFrameTransferPayloadLen) };
     enum { BufferSize = NeedsBuffer ? DataTypeMaxByteLen : 0 };
-    enum { NumStaticBufs = NeedsBuffer ? (NumStaticBufs_ ? NumStaticBufs_ : 1) : 0 };
+#if UAVCAN_TINY
+    enum { NumStaticBufs = 0 };
+    enum { NumStaticReceivers = 0 };
+#else
+    enum { NumStaticBufs = NeedsBuffer ? NumStaticBufs_: 0 };
+    enum { NumStaticReceivers = NumStaticReceivers_ };
+#endif
 
 public:
-    // TODO: support for zero static bufs
-    typedef TransferListener<BufferSize, NumStaticBufs, NumStaticReceivers_ ? NumStaticReceivers_ : 1> Type;
+    typedef TransferListener<BufferSize, NumStaticBufs, NumStaticReceivers> Type;
 };
 
 

libuavcan/include/uavcan/node/node.hpp

@@ -30,8 +30,14 @@ namespace uavcan
 {
 
 template <std::size_t MemPoolSize_,
+#if UAVCAN_TINY
+          unsigned OutgoingTransferRegistryStaticEntries = 0,
+          unsigned OutgoingTransferMaxPayloadLen = 264
+#else
           unsigned OutgoingTransferRegistryStaticEntries = 10,
-          unsigned OutgoingTransferMaxPayloadLen = MaxTransferPayloadLen>
+          unsigned OutgoingTransferMaxPayloadLen = MaxTransferPayloadLen
+#endif
+          >
 class UAVCAN_EXPORT Node : public INode
 {
     enum

libuavcan/include/uavcan/node/service_server.hpp

@@ -27,8 +27,14 @@ template <typename DataType_,
           typename Callback_ = void (*)(const ReceivedDataStructure<typename DataType_::Request>&,
                                         typename DataType_::Response&),
 #endif
+#if UAVCAN_TINY
+          unsigned NumStaticReceivers = 0,
+          unsigned NumStaticBufs = 0
+#else
           unsigned NumStaticReceivers = 2,
-          unsigned NumStaticBufs = 1>
+          unsigned NumStaticBufs = 1
+#endif
+          >
 class UAVCAN_EXPORT ServiceServer
     : public GenericSubscriber<DataType_, typename DataType_::Request,
                                typename TransferListenerInstantiationHelper<typename DataType_::Request,

libuavcan/include/uavcan/node/subscriber.hpp

@@ -25,8 +25,14 @@ template <typename DataType_,
 #else
           typename Callback_ = void (*)(const ReceivedDataStructure<DataType_>&),
 #endif
+#if UAVCAN_TINY
+          unsigned NumStaticReceivers = 0,
+          unsigned NumStaticBufs = 0
+#else
           unsigned NumStaticReceivers = 2,
-          unsigned NumStaticBufs = 1>
+          unsigned NumStaticBufs = 1
+#endif
+          >
 class UAVCAN_EXPORT Subscriber
     : public GenericSubscriber<DataType_, DataType_,
                                typename TransferListenerInstantiationHelper<DataType_, NumStaticReceivers,