Qt/Options: Configure datacarrier[size] using rwconf

src/qt/optionsdialog.cpp

@@ -265,6 +265,12 @@ OptionsDialog::OptionsDialog(QWidget* parent, bool enableWallet)
     verticalLayout_Spamfiltering->addWidget(rejectbaremultisig);
     FixTabOrder(rejectbaremultisig);
 
+    datacarriersize = new QSpinBox(groupBox_Spamfiltering);
+    datacarriersize->setMinimum(0);
+    datacarriersize->setMaximum(std::numeric_limits<int>::max());
+    datacarriersize->setToolTip(tr("Since 2014, a specific method for attaching arbitrary data to transactions has been recognised as not requiring space in the coin database. Since it is sometimes impractical to detect small spam disguised as ordinary transactions, it is sometimes considered beneficial to treat these less harmful data attachments as equals to legitimate usage."));
+    CreateOptionUI(verticalLayout_Spamfiltering, datacarriersize, tr("Ignore transactions with additional data larger than %s bytes."));
+
     verticalLayout_Mempool->addWidget(groupBox_Spamfiltering);
 
     verticalLayout_Mempool->addItem(new QSpacerItem(20, 40, QSizePolicy::Minimum, QSizePolicy::Expanding));
@@ -523,6 +529,7 @@ void OptionsDialog::setMapper()
     mapper->addMapping(limitdescendantcount, OptionsModel::limitdescendantcount);
     mapper->addMapping(limitdescendantsize, OptionsModel::limitdescendantsize);
     mapper->addMapping(rejectbaremultisig, OptionsModel::rejectbaremultisig);
+    mapper->addMapping(datacarriersize, OptionsModel::datacarriersize);
 
     /* Window */
 #ifndef Q_OS_MACOS

src/qt/optionsdialog.h

@@ -101,6 +101,7 @@ private:
     QSpinBox *limitdescendantcount;
     QSpinBox *limitdescendantsize;
     QCheckBox *rejectbaremultisig;
+    QSpinBox *datacarriersize;
 };
 
 #endif // BITCOIN_QT_OPTIONSDIALOG_H

src/qt/optionsmodel.cpp

@@ -660,6 +660,8 @@ QVariant OptionsModel::getOption(OptionID option, const std::string& suffix) con
         return qlonglong(node().mempool().m_opts.limits.descendant_size_vbytes / 1'000);
     case rejectbaremultisig:
         return !node().mempool().m_opts.permit_bare_multisig;
+    case datacarriersize:
+        return qlonglong(node().mempool().m_opts.max_datacarrier_bytes.value_or(0));
     default:
         return QVariant();
     }
@@ -1097,6 +1099,22 @@ bool OptionsModel::setOption(OptionID option, const QVariant& value, const std::
             gArgs.ModifyRWConfigFile("permitbaremultisig", strprintf("%d", fNewValue));
         }
         break;
+    case datacarriersize:
+        if (changed()) {
+            const int nNewSize = value.toInt();
+            const bool fNewEn = (nNewSize > 0);
+            if (fNewEn) {
+                if (!node().mempool().m_opts.max_datacarrier_bytes.has_value()) {
+                    gArgs.ModifyRWConfigFile("datacarrier", strprintf("%d", fNewEn));
+                }
+                gArgs.ModifyRWConfigFile("datacarriersize", value.toString().toStdString());
+                node().mempool().m_opts.max_datacarrier_bytes = nNewSize;
+            } else {
+                gArgs.ModifyRWConfigFile("datacarrier", "0");
+                node().mempool().m_opts.max_datacarrier_bytes = std::nullopt;
+            }
+        }
+        break;
     default:
         break;
     }

src/qt/optionsmodel.h

@@ -92,6 +92,7 @@ public:
         limitdescendantcount,
         limitdescendantsize,
         rejectbaremultisig,     // bool
+        datacarriersize,
         OptionIDRowCount,
     };