Make Decompilation asynchronous (#1721)

src/common/Decompiler.cpp

@@ -51,6 +51,7 @@ Decompiler::Decompiler(const QString &id, const QString &name, QObject *parent)
 R2DecDecompiler::R2DecDecompiler(QObject *parent)
     : Decompiler("r2dec", "r2dec", parent)
 {
+    task = nullptr;
 }
 
 bool R2DecDecompiler::isAvailable()
@@ -58,47 +59,59 @@ bool R2DecDecompiler::isAvailable()
     return Core()->cmdList("e cmd.pdc=?").contains(QStringLiteral("pdd"));
 }
 
-AnnotatedCode R2DecDecompiler::decompileAt(RVA addr)
+void R2DecDecompiler::decompileAt(RVA addr)
 {
-    AnnotatedCode code = {};
-    QString s;
-
-    QJsonObject json = Core()->cmdj("pddj @ " + QString::number(addr)).object();
-    if (json.isEmpty()) {
-        return code;
+    if (task) {
+        return;
     }
 
-    for (const auto &line : json["log"].toArray()) {
-        if (!line.isString()) {
-            continue;
-        }
-        code.code.append(line.toString() + "\n");
-    }
+    task = new R2Task("pddj @ " + QString::number(addr));
+    connect(task, &R2Task::finished, this, [this]() {
+        AnnotatedCode code = {};
+        QString s;
 
-    auto linesArray = json["lines"].toArray();
-    for (const auto &line : linesArray) {
-        QJsonObject lineObject = line.toObject();
-        if (lineObject.isEmpty()) {
-            continue;
+        QJsonObject json = task->getResultJson().object();
+        delete task;
+        task = nullptr;
+        if (json.isEmpty()) {
+            code.code = tr("Failed to parse JSON from r2dec");
+            emit finished(code);
+            return;
         }
-        CodeAnnotation annotation = {};
-        annotation.type = CodeAnnotation::Type::Offset;
-        annotation.start = code.code.length();
-        code.code.append(lineObject["str"].toString() + "\n");
-        annotation.end = code.code.length();
-        bool ok;
-        annotation.offset.offset = lineObject["offset"].toVariant().toULongLong(&ok);
-        if (ok) {
-            code.annotations.push_back(annotation);
-        }
-    }
 
-    for (const auto &line : json["errors"].toArray()) {
-        if (!line.isString()) {
-            continue;
+        for (const auto &line : json["log"].toArray()) {
+            if (!line.isString()) {
+                continue;
+            }
+            code.code.append(line.toString() + "\n");
         }
-        code.code.append(line.toString() + "\n");
-    }
 
-    return code;
-}
+        auto linesArray = json["lines"].toArray();
+        for (const auto &line : linesArray) {
+            QJsonObject lineObject = line.toObject();
+            if (lineObject.isEmpty()) {
+                continue;
+            }
+            CodeAnnotation annotation = {};
+            annotation.type = CodeAnnotation::Type::Offset;
+            annotation.start = code.code.length();
+            code.code.append(lineObject["str"].toString() + "\n");
+            annotation.end = code.code.length();
+            bool ok;
+            annotation.offset.offset = lineObject["offset"].toVariant().toULongLong(&ok);
+            if (ok) {
+                code.annotations.push_back(annotation);
+            }
+        }
+
+        for (const auto &line : json["errors"].toArray()) {
+            if (!line.isString()) {
+                continue;
+            }
+            code.code.append(line.toString() + "\n");
+        }
+
+        emit finished(code);
+    });
+    task->startTask();
+}

src/common/Decompiler.h

@@ -2,6 +2,7 @@
 #define DECOMPILER_H
 
 #include "CutterCommon.h"
+#include "R2Task.h"
 
 #include <QString>
 #include <QObject>
@@ -54,19 +55,30 @@ public:
     Decompiler(const QString &id, const QString &name, QObject *parent = nullptr);
     virtual ~Decompiler() = default;
 
-    QString getId() const   { return id; }
-    QString getName() const { return name; }
+    QString getId() const       { return id; }
+    QString getName() const     { return name; }
+    virtual bool isRunning()    { return false; }
+    virtual bool isCancelable() { return false; }
 
-    virtual AnnotatedCode decompileAt(RVA addr) =0;
+    virtual void decompileAt(RVA addr) =0;
+    virtual void cancel() {}
+
+signals:
+    void finished(AnnotatedCode code);
 };
 
 class R2DecDecompiler: public Decompiler
 {
     Q_OBJECT
 
+private:
+    R2Task *task;
+
 public:
     explicit R2DecDecompiler(QObject *parent = nullptr);
-    AnnotatedCode decompileAt(RVA addr) override;
+    void decompileAt(RVA addr) override;
+
+    bool isRunning() override    { return task != nullptr; }
 
     static bool isAvailable();
 };

src/common/R2Task.cpp

@@ -47,6 +47,11 @@ QString R2Task::getResult()
     return QString::fromUtf8(task->res);
 }
 
+QJsonDocument R2Task::getResultJson()
+{
+    return Core()->parseJson(task->res, task->cmd);
+}
+
 const char *R2Task::getResultRaw()
 {
     return task->res;

src/common/R2Task.h

@@ -23,6 +23,7 @@ public:
     void joinTask();
 
     QString getResult();
+    QJsonDocument getResultJson();
     const char *getResultRaw();
 
 signals:

src/widgets/PseudocodeWidget.cpp

@@ -41,13 +41,14 @@ PseudocodeWidget::PseudocodeWidget(MainWindow *main, QAction *action) :
         if (dec->getId() == selectedDecompilerId) {
             ui->decompilerComboBox->setCurrentIndex(ui->decompilerComboBox->count() - 1);
         }
+        connect(dec, &Decompiler::finished, this, &PseudocodeWidget::decompilationFinished);
     }
 
-    if(decompilers.size() <= 1) {
-        ui->decompilerComboBox->setEnabled(false);
-        if (decompilers.isEmpty()) {
-            ui->textEdit->setPlainText(tr("No Decompiler available."));
-        }
+    decompilerSelectionEnabled = decompilers.size() > 1;
+    ui->decompilerComboBox->setEnabled(decompilerSelectionEnabled);
+
+    if (decompilers.isEmpty()) {
+        ui->textEdit->setPlainText(tr("No Decompiler available."));
     }
 
     connect(ui->decompilerComboBox, static_cast<void(QComboBox::*)(int)>(&QComboBox::currentIndexChanged), this, &PseudocodeWidget::decompilerSelected);
@@ -61,6 +62,7 @@ PseudocodeWidget::PseudocodeWidget(MainWindow *main, QAction *action) :
     connect(mCtxMenu, &QMenu::triggered, this, &PseudocodeWidget::refreshPseudocode);
     addActions(mCtxMenu->actions());
 
+    ui->progressLabel->setVisible(false);
     doRefresh(RVA_INVALID);
 }
 
@@ -74,7 +76,7 @@ void PseudocodeWidget::doRefresh(RVA addr)
     }
 
     Decompiler *dec = Core()->getDecompilerById(ui->decompilerComboBox->currentData().toString());
-    if (!dec) {
+    if (!dec || dec->isRunning()) {
         return;
     }
 
@@ -83,10 +85,34 @@ void PseudocodeWidget::doRefresh(RVA addr)
         return;
     }
 
-    code = dec->decompileAt(addr);
+    dec->decompileAt(addr);
+    if (dec->isRunning()) {
+        ui->progressLabel->setVisible(true);
+        ui->decompilerComboBox->setEnabled(false);
+        if (dec->isCancelable()) {
+            ui->refreshButton->setText(tr("Cancel"));
+        } else {
+            ui->refreshButton->setEnabled(false);
+        }
+        return;
+    }
+}
+
+void PseudocodeWidget::refreshPseudocode()
+{
+    doRefresh(Core()->getOffset());
+}
+
+void PseudocodeWidget::decompilationFinished(AnnotatedCode code)
+{
+    ui->progressLabel->setVisible(false);
+    ui->decompilerComboBox->setEnabled(decompilerSelectionEnabled);
+    ui->refreshButton->setText(tr("Refresh"));
+    ui->refreshButton->setEnabled(true);
+
+    this->code = code;
     if (code.code.isEmpty()) {
-        ui->textEdit->setPlainText(tr("Cannot decompile at") + " " + RAddressString(
-                                  addr) + " " + tr("(Not a function?)"));
+        ui->textEdit->setPlainText(tr("Cannot decompile at this address (Not a function?)"));
         return;
     } else {
         connectCursorPositionChanged(true);
@@ -96,11 +122,6 @@ void PseudocodeWidget::doRefresh(RVA addr)
     }
 }
 
-void PseudocodeWidget::refreshPseudocode()
-{
-    doRefresh(Core()->getOffset());
-}
-
 void PseudocodeWidget::decompilerSelected()
 {
     Config()->setSelectedDecompiler(ui->decompilerComboBox->currentData().toString());

src/widgets/PseudocodeWidget.h

@@ -36,11 +36,13 @@ private slots:
     void decompilerSelected();
     void cursorPositionChanged();
     void seekChanged();
+    void decompilationFinished(AnnotatedCode code);
 
 private:
     std::unique_ptr<Ui::PseudocodeWidget> ui;
 
     QSyntaxHighlighter *syntaxHighlighter;
+    bool decompilerSelectionEnabled;
 
     AnnotatedCode code;
 

src/widgets/PseudocodeWidget.ui

@@ -49,6 +49,20 @@
         </property>
        </widget>
       </item>
+      <item>
+       <layout class="QHBoxLayout" name="progressLayout">
+        <property name="leftMargin">
+         <number>8</number>
+        </property>
+        <item>
+         <widget class="QLabel" name="progressLabel">
+          <property name="text">
+           <string>Decompiling...</string>
+          </property>
+         </widget>
+        </item>
+       </layout>
+      </item>
       <item>
        <spacer name="horizontalSpacer">
         <property name="orientation">
@@ -70,7 +84,7 @@
        </widget>
       </item>
       <item>
-       <widget class="QComboBox" name="decompilerComboBox" />
+       <widget class="QComboBox" name="decompilerComboBox"/>
       </item>
      </layout>
     </item>