From d0a75e0a8415e519608c48d4985c3d911e805748 Mon Sep 17 00:00:00 2001
From: wmayer <wmayer@users.sourceforge.net>
Date: Thu, 21 Oct 2021 16:22:11 +0200
Subject: [PATCH] Sketcher: fix segmentation fault when using sketch validation
 dialog after document has been closed Therefore replace the raw pointer of
 SketchObject with the template class WeakPtrT. This class will be notified as
 soon as its handled object will be deleted.

---
 .../Sketcher/Gui/TaskSketcherValidation.cpp   | 50 +++++++++++++++++--
 src/Mod/Sketcher/Gui/TaskSketcherValidation.h |  3 +-
 2 files changed, 47 insertions(+), 6 deletions(-)

diff --git a/src/Mod/Sketcher/Gui/TaskSketcherValidation.cpp b/src/Mod/Sketcher/Gui/TaskSketcherValidation.cpp
index afd57cf1ba..11b9eb0cd2 100644
--- a/src/Mod/Sketcher/Gui/TaskSketcherValidation.cpp
+++ b/src/Mod/Sketcher/Gui/TaskSketcherValidation.cpp
@@ -107,6 +107,9 @@ void SketcherValidation::changeEvent(QEvent *e)
 
 void SketcherValidation::on_findButton_clicked()
 {
+    if (sketch.expired())
+        return;
+
     double prec = Precision::Confusion();
     bool ok;
     double conv;
@@ -150,6 +153,9 @@ void SketcherValidation::on_findButton_clicked()
 
 void SketcherValidation::on_fixButton_clicked()
 {
+    if (sketch.expired())
+        return;
+
     // undo command open
     App::Document* doc = sketch->getDocument();
     doc->openTransaction("add coincident constraint");
@@ -167,6 +173,9 @@ void SketcherValidation::on_fixButton_clicked()
 
 void SketcherValidation::on_highlightButton_clicked()
 {
+    if (sketch.expired())
+        return;
+
     std::vector<Base::Vector3d> points;
 
     points = sketchAnalyser.getOpenVertices();
@@ -178,6 +187,9 @@ void SketcherValidation::on_highlightButton_clicked()
 
 void SketcherValidation::on_findConstraint_clicked()
 {
+    if (sketch.expired())
+        return;
+
     if (sketch->evaluateConstraints()) {
         QMessageBox::information(this, tr("No invalid constraints"),
             tr("No invalid constraints found"));
@@ -192,12 +204,18 @@ void SketcherValidation::on_findConstraint_clicked()
 
 void SketcherValidation::on_fixConstraint_clicked()
 {
+    if (sketch.expired())
+        return;
+
     sketch->validateConstraints();
     ui->fixConstraint->setEnabled(false);
 }
 
 void SketcherValidation::on_findReversed_clicked()
 {
+    if (sketch.expired())
+        return;
+
     std::vector<Base::Vector3d> points;
     const std::vector<Part::Geometry *>& geom = sketch->getExternalGeometry();
     for (std::size_t i=0; i<geom.size(); i++) {
@@ -241,6 +259,9 @@ void SketcherValidation::on_findReversed_clicked()
 
 void SketcherValidation::on_swapReversed_clicked()
 {
+    if (sketch.expired())
+        return;
+
     App::Document* doc = sketch->getDocument();
     doc->openTransaction("Sketch porting");
 
@@ -255,6 +276,9 @@ void SketcherValidation::on_swapReversed_clicked()
 
 void SketcherValidation::on_orientLockEnable_clicked()
 {
+    if (sketch.expired())
+        return;
+
     App::Document* doc = sketch->getDocument();
     doc->openTransaction("Constraint orientation lock");
 
@@ -269,6 +293,9 @@ void SketcherValidation::on_orientLockEnable_clicked()
 
 void SketcherValidation::on_orientLockDisable_clicked()
 {
+    if (sketch.expired())
+        return;
+
     App::Document* doc = sketch->getDocument();
     doc->openTransaction("Constraint orientation unlock");
 
@@ -284,6 +311,9 @@ void SketcherValidation::on_orientLockDisable_clicked()
 
 void SketcherValidation::on_delConstrExtr_clicked()
 {
+    if (sketch.expired())
+        return;
+
     int reply;
     reply =  QMessageBox::question(this,
                         tr("Delete constraints to external geom."),
@@ -337,21 +367,28 @@ void SketcherValidation::showPoints(const std::vector<Base::Vector3d>& pts)
     }
     coords->point.finishEditing();
 
-    Gui::ViewProvider* vp = Gui::Application::Instance->getViewProvider(sketch);
-    vp->getRoot()->addChild(coincidenceRoot);
+    if (!sketch.expired()) {
+        Gui::ViewProvider* vp = Gui::Application::Instance->getViewProvider(sketch.get());
+        vp->getRoot()->addChild(coincidenceRoot);
+    }
 }
 
 void SketcherValidation::hidePoints()
 {
     if (coincidenceRoot) {
-        Gui::ViewProvider* vp = Gui::Application::Instance->getViewProvider(sketch);
-        vp->getRoot()->removeChild(coincidenceRoot);
-        coincidenceRoot = 0;
+        if (!sketch.expired()) {
+            Gui::ViewProvider* vp = Gui::Application::Instance->getViewProvider(sketch.get());
+            vp->getRoot()->removeChild(coincidenceRoot);
+        }
+        coincidenceRoot = nullptr;
     }
 }
 
 void SketcherValidation::on_findDegenerated_clicked()
 {
+    if (sketch.expired())
+        return;
+
     double prec = Precision::Confusion();
     int count = sketchAnalyser.detectDegeneratedGeometries(prec);
 
@@ -369,6 +406,9 @@ void SketcherValidation::on_findDegenerated_clicked()
 
 void SketcherValidation::on_fixDegenerated_clicked()
 {
+    if (sketch.expired())
+        return;
+
     // undo command open
     App::Document* doc = sketch->getDocument();
     doc->openTransaction("Remove degenerated geometry");
diff --git a/src/Mod/Sketcher/Gui/TaskSketcherValidation.h b/src/Mod/Sketcher/Gui/TaskSketcherValidation.h
index 127a561e65..c787587385 100644
--- a/src/Mod/Sketcher/Gui/TaskSketcherValidation.h
+++ b/src/Mod/Sketcher/Gui/TaskSketcherValidation.h
@@ -27,6 +27,7 @@
 #include <vector>
 #include <memory>
 #include <Base/Vector3D.h>
+#include <App/DocumentObserver.h>
 #include <Gui/TaskView/TaskDialog.h>
 #include <Mod/Sketcher/App/SketchAnalysis.h>
 
@@ -67,7 +68,7 @@ private:
 
 private:
     std::unique_ptr<Ui_TaskSketcherValidation> ui;
-    Sketcher::SketchObject* sketch;
+    App::WeakPtrT<Sketcher::SketchObject> sketch;
     Sketcher::SketchAnalysis sketchAnalyser;
     SoGroup* coincidenceRoot;
 };