Enable customising node policy for datacarrier data size with a -datacarriersize option

src/script/standard.cpp

@@ -15,6 +15,8 @@ using namespace std;
 
 typedef vector<unsigned char> valtype;
 
+unsigned nMaxDatacarrierBytes = MAX_OP_RETURN_RELAY;
+
 CScriptID::CScriptID(const CScript& in) : uint160(in.size() ? Hash160(in.begin(), in.end()) : 0) {}
 
 const char* GetTxnOutputType(txnouttype t)
@@ -139,8 +141,8 @@ bool Solver(const CScript& scriptPubKey, txnouttype& typeRet, vector<vector<unsi
             }
             else if (opcode2 == OP_SMALLDATA)
             {
-                // small pushdata, <= MAX_OP_RETURN_RELAY bytes
-                if (vch1.size() > MAX_OP_RETURN_RELAY)
+                // small pushdata, <= nMaxDatacarrierBytes
+                if (vch1.size() > nMaxDatacarrierBytes)
                     break;
             }
             else if (opcode1 != opcode2 || vch1 != vch2)

src/script/standard.h

@@ -26,6 +26,7 @@ public:
 };
 
 static const unsigned int MAX_OP_RETURN_RELAY = 40;      // bytes
+extern unsigned nMaxDatacarrierBytes;
 
 // Mandatory script verification flags that all new blocks must comply with for
 // them to be valid. (but old blocks may not comply with) Currently just P2SH,