ProtocolRawMsg: const accessors and takeBuffer(); takeable buffers for encoded messages

components/comms/CommsChannelMsg/CommsChannelMsg.h

@@ -190,11 +190,24 @@ class CommsChannelMsg
         return _cmdVector;
     }
 
+    // Whether the buffer may be taken (moved out, leaving it empty) by the channel sending the message, rather
+    // than copied. Set by a protocol codec on a message it made to send and doesn't use afterwards - a message
+    // passed on as it is may be sent again (e.g. on each channel), so its buffer mustn't be taken
+    void setBufTakeable(bool takeable)
+    {
+        _bufTakeable = takeable;
+    }
+    bool isBufTakeable() const
+    {
+        return _bufTakeable;
+    }
+
 private:
     uint32_t _channelID;
     CommsMsgProtocol _msgProtocol;
     uint32_t _msgNum;
     CommsMsgTypeCode _msgTypeCode;
+    bool _bufTakeable = false;
 #ifdef IMPLEMENT_NO_PSRAM_FOR_COMMS_CHANNEL_MSG
     std::vector<uint8_t> _cmdVector;
 #else

components/comms/ProtocolRICSerial/ProtocolRICSerial.cpp

@@ -162,6 +162,9 @@ void ProtocolRICSerial::encodeTxMsgAndSend(CommsChannelMsg& msg)
         _pHDLC->appendFramePayload(encoded, fcs, ricSerialRec, sizeof(ricSerialRec));
         _pHDLC->appendFramePayload(encoded, fcs, msg.getBuf(), msg.getBufLen());
         _pHDLC->appendFrameEnd(encoded, fcs);
+
+        // Nothing uses the encoded message after it is sent, so the channel may take its buffer
+        encodedMsg.setBufTakeable(true);
 #endif
 
         // Debug

components/comms/ProtocolRawMsg/ProtocolRawMsg.h

@@ -41,6 +41,17 @@ class ProtocolRawMsg
         _cmdVector.assign(pBuf, pBuf+bufLen);
     }
 
+    // Take the contents of a buffer without copying (it is left empty)
+    void takeBuffer(SpiramAwareUint8Vector& buf)
+    {
+#ifdef IMPLEMENT_NO_PSRAM_FOR_PROTOCOL_RAW_MSG
+        _cmdVector.assign(buf.begin(), buf.end());
+        buf.clear();
+#else
+        _cmdVector.swap(buf);
+#endif
+    }
+
     void setBufferSize(uint32_t bufSize)
     {
         _cmdVector.resize(bufSize);
@@ -55,11 +66,11 @@ class ProtocolRawMsg
     }
 
     // Access to command vector
-    const uint8_t* getBuf()
+    const uint8_t* getBuf() const
     {
         return _cmdVector.data();
     }
-    uint32_t getBufLen()
+    uint32_t getBufLen() const
     {
         return _cmdVector.size();
     }