Fix "return" key in disassembler widget (rizinorg#3090)

Fix graph jumps

Author: Yappa

src/common/CutterSeekable.cpp

@@ -66,6 +66,7 @@ void CutterSeekable::seekToReference(RVA offset)
     }
 
     RVA target;
+    // finds the xrefs for calls, lea, and jmp
     QList<XrefDescription> refs = Core()->getXRefs(offset, false, false);
 
     if (refs.length()) {

src/common/DisassemblyPreview.cpp

@@ -89,3 +89,13 @@ RVA DisassemblyPreview::readDisassemblyOffset(QTextCursor tc)
 
     return userData->line.offset;
 }
+
+RVA DisassemblyPreview::readDisassemblyArrow(QTextCursor tc)
+{
+    auto userData = getUserData(tc.block());
+    if (!userData && userData->line.arrow != RVA_INVALID) {
+        return RVA_INVALID;
+    }
+
+    return userData->line.arrow;
+}

src/common/DisassemblyPreview.h

@@ -41,5 +41,11 @@ bool showDisasPreview(QWidget *parent, const QPoint &pointOfEvent, const RVA off
  * @return The disassembly offset of the hovered asm text
  */
 RVA readDisassemblyOffset(QTextCursor tc);
+
+/*!
+ * @brief Reads the arrow offset for the cursor position
+ * @return The jump address of the hovered asm text
+ */
+RVA readDisassemblyArrow(QTextCursor tc);
 }
 #endif

src/widgets/DisassemblerGraphView.cpp

@@ -914,7 +914,36 @@ void DisassemblerGraphView::blockDoubleClicked(GraphView::GraphBlock &block, QMo
                                                QPoint pos)
 {
     Q_UNUSED(event);
-    seekable->seekToReference(getAddrForMouseEvent(block, &pos));
+    RVA arrow;
+    RVA offset = getAddrForMouseEvent(block, &pos);
+    DisassemblyBlock *db = blockForAddress(offset);
+
+    Instr lastInstruction = db->instrs.back();
+
+    // Handle the blocks with just one path
+    if (offset == lastInstruction.addr && db->false_path == RVA_INVALID) {
+        seekable->seek(db->true_path);
+        return;
+    }
+
+    // Handle blocks with two paths
+    if (offset == lastInstruction.addr && db->false_path != RVA_INVALID) {
+        // gets the offset for the next instruction
+        RVA nextOffset = lastInstruction.addr + lastInstruction.size;
+        // sets "arrow" to the path that isn't going to the next offset
+        if (db->false_path == nextOffset) {
+            arrow = db->true_path;
+        }
+        if (db->true_path == nextOffset){
+            arrow = db->false_path;
+        }
+
+        seekable->seek(arrow);
+        return;
+    }
+
+    // Handle "call" instruction to functions
+    seekable->seekToReference(offset);
 }
 
 void DisassemblerGraphView::blockHelpEvent(GraphView::GraphBlock &block, QHelpEvent *event,

src/widgets/DisassemblyWidget.cpp

@@ -613,6 +613,13 @@ void DisassemblyWidget::moveCursorRelative(bool up, bool page)
 
 void DisassemblyWidget::jumpToOffsetUnderCursor(const QTextCursor &cursor)
 {
+    // Handles "jmp" and conditonal jump instructions
+    RVA arrow = DisassemblyPreview::readDisassemblyArrow(cursor);
+    if (arrow != RVA_INVALID) {
+        seekable->seek(arrow);
+    }
+
+    // Handles "call" and "lea" instructions
     RVA offset = DisassemblyPreview::readDisassemblyOffset(cursor);
     seekable->seekToReference(offset);
 }

src/widgets/DisassemblyWidget.h

@@ -99,6 +99,7 @@ protected slots:
     void moveCursorRelative(bool up, bool page);
 
     void jumpToOffsetUnderCursor(const QTextCursor &);
+    void jumpToArrowOffsetUnderCursor(const QTextCursor &);
 };
 
 class DisassemblyScrollArea : public QAbstractScrollArea