Reduce amount selected

OmniLayer · Dec 13, 2020 · b0a01dc · b0a01dc
1 parent 3751c17
commit b0a01dc
Show file tree

Hide file tree

Showing 4 changed files with 17 additions and 7 deletions.
diff --git a/src/omnicore/encoding.cpp b/src/omnicore/encoding.cpp
@@ -23,7 +23,7 @@
  * https://github.com/mastercoin-MSC/spec#class-b-transactions-also-known-as-the-multisig-method
  */
 bool OmniCore_Encode_ClassB(const std::string& senderAddress, const CPubKey& redeemingPubKey,
-        const std::vector<unsigned char>& vchPayload, std::vector<std::pair<CScript, int64_t> >& vecOutputs)
+        const std::vector<unsigned char>& vchPayload, std::vector<std::pair<CScript, int64_t> >& vecOutputs, CAmount *outputAmount)
 {
     unsigned int nRemainingBytes = vchPayload.size();
     unsigned int nNextByte = 0;
@@ -65,11 +65,15 @@ bool OmniCore_Encode_ClassB(const std::string& senderAddress, const CPubKey& red
 
         // Push back a bare multisig output with obfuscated data
         CScript scriptMultisigOut = GetScriptForMultisig(1, vKeys);
+        if (outputAmount)
+            *outputAmount += OmniGetDustThreshold(scriptMultisigOut);
         vecOutputs.push_back(std::make_pair(scriptMultisigOut, OmniGetDustThreshold(scriptMultisigOut)));
     }
 
     // Add the Exodus marker output
     CScript scriptExodusOutput = GetScriptForDestination(ExodusAddress());
+    if (outputAmount)
+        *outputAmount += OmniGetDustThreshold(scriptExodusOutput);
     vecOutputs.push_back(std::make_pair(scriptExodusOutput, OmniGetDustThreshold(scriptExodusOutput)));
     return true;
 }

diff --git a/src/omnicore/encoding.h b/src/omnicore/encoding.h
@@ -4,6 +4,7 @@
 class CPubKey;
 class CTxOut;
 
+#include <amount.h>
 #include <script/script.h>
 
 #include <stdint.h>
@@ -12,7 +13,8 @@ class CTxOut;
 #include <vector>
 
 /** Embeds a payload in obfuscated multisig outputs, and adds an Exodus marker output. */
-bool OmniCore_Encode_ClassB(const std::string& senderAddress, const CPubKey& redeemingPubKey, const std::vector<unsigned char>& vchPayload, std::vector<std::pair<CScript, int64_t> >& vecOutputs);
+bool OmniCore_Encode_ClassB(const std::string& senderAddress, const CPubKey& redeemingPubKey, const std::vector<unsigned char>& vchPayload,
+                            std::vector<std::pair<CScript, int64_t> >& vecOutputs, CAmount* outputAmount = nullptr);
 
 /** Embeds a payload in an OP_RETURN output, prefixed with a transaction marker. */
 bool OmniCore_Encode_ClassC(const std::vector<unsigned char>& vecPayload, std::vector<std::pair<CScript, int64_t> >& vecOutputs);

diff --git a/src/omnicore/wallettxbuilder.cpp b/src/omnicore/wallettxbuilder.cpp
@@ -66,8 +66,8 @@ int WalletTxBuilder(
     // Next, we set the change address to the sender
     coinControl.destChange = DecodeDestination(senderAddress);
 
-    // Select the inputs
-    if (0 > mastercore::SelectCoins(*iWallet, senderAddress, coinControl, referenceAmount)) { return MP_INPUTS_INVALID; }
+    // Amount required for outputs
+    CAmount outputAmount{0};
 
     // Encode the data outputs
     switch(omniTxClass) {
@@ -77,7 +77,7 @@ int WalletTxBuilder(
             if (!AddressToPubKey(iWallet, sAddress, redeemingPubKey)) {
                 return MP_REDEMP_BAD_VALIDATION;
             }
-            if (!OmniCore_Encode_ClassB(senderAddress,redeemingPubKey,payload,vecSend)) { return MP_ENCODING_ERROR; }
+            if (!OmniCore_Encode_ClassB(senderAddress, redeemingPubKey, payload, vecSend, &outputAmount)) { return MP_ENCODING_ERROR; }
         break; }
         case OMNI_CLASS_C:
             if(!OmniCore_Encode_ClassC(payload,vecSend)) { return MP_ENCODING_ERROR; }
@@ -87,9 +87,13 @@ int WalletTxBuilder(
     // Then add a paytopubkeyhash output for the recipient (if needed) - note we do this last as we want this to be the highest vout
     if (!receiverAddress.empty()) {
         CScript scriptPubKey = GetScriptForDestination(DecodeDestination(receiverAddress));
+        outputAmount += 0 < referenceAmount ? referenceAmount : OmniGetDustThreshold(scriptPubKey);
         vecSend.push_back(std::make_pair(scriptPubKey, 0 < referenceAmount ? referenceAmount : OmniGetDustThreshold(scriptPubKey)));
     }
 
+    // Select the inputs
+    if (0 > mastercore::SelectCoins(*iWallet, senderAddress, coinControl, outputAmount)) { return MP_INPUTS_INVALID; }
+
     // Now we have what we need to pass to the wallet to create the transaction, perform some checks first
 
     if (!coinControl.HasSelected()) return MP_ERR_INPUTSELECT_FAIL;

diff --git a/src/omnicore/walletutils.cpp b/src/omnicore/walletutils.cpp
@@ -208,8 +208,8 @@ int64_t SelectCoins(interfaces::Wallet& iWallet, const std::string& fromAddress,
     int64_t nTotal = 0;
     int nHeight = ::ChainActive().Height();
 
-    // select coins to cover up to 20 kB max. transaction size
-    CAmount nMax = 20 * GetEstimatedFeePerKb(iWallet);
+    // select coins to cover up to 3 kB max. transaction size
+    CAmount nMax = 3 * GetEstimatedFeePerKb(iWallet);
 
     // if referenceamount is set it is needed to be accounted for here too
     if (0 < additional) nMax += additional;