HackStudio: Show a backtrace in the debug information tab

DevTools/HackStudio/Debugger/BacktraceModel.cpp

@@ -0,0 +1,62 @@
+/*
+ * Copyright (c) 2020, Itamar S. <itamar8910@gmail.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "BacktraceModel.h"
+#include "Debugger.h"
+
+RefPtr<BacktraceModel> BacktraceModel::create(const PtraceRegisters& regs)
+{
+    return adopt(*new BacktraceModel(create_backtrace(regs)));
+}
+
+GUI::Variant BacktraceModel::data(const GUI::ModelIndex& index, Role role) const
+{
+    if (role == Role::Display) {
+        auto& frame = m_frames.at(index.row());
+        return frame.function_name;
+    }
+    return {};
+}
+
+Vector<BacktraceModel::FrameInfo> BacktraceModel::create_backtrace(const PtraceRegisters& regs)
+{
+    u32 current_ebp = regs.ebp;
+    u32 current_instruction = regs.eip;
+    Vector<BacktraceModel::FrameInfo> frames;
+    do {
+        const auto& debug_info = Debugger::the().session()->debug_info();
+        String name = debug_info.name_of_containing_function(current_instruction);
+        if (name.is_null()) {
+            dbg() << "BacktraceModel: couldn't find containing function for address: " << (void*)current_instruction;
+            break;
+        }
+
+        frames.append({ name, current_instruction });
+        current_instruction = Debugger::the().session()->peek(reinterpret_cast<u32*>(current_ebp + 4)).value();
+        current_ebp = Debugger::the().session()->peek(reinterpret_cast<u32*>(current_ebp)).value();
+    } while (current_ebp);
+    return frames;
+}

DevTools/HackStudio/Debugger/BacktraceModel.h

@@ -0,0 +1,64 @@
+/*
+ * Copyright (c) 2020, Itamar S. <itamar8910@gmail.com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#pragma once
+#include <AK/Vector.h>
+#include <LibGUI/ListView.h>
+#include <LibGUI/Model.h>
+#include <sys/arch/i386/regs.h>
+
+class BacktraceModel final : public GUI::Model {
+public:
+    static RefPtr<BacktraceModel> create(const PtraceRegisters& regs);
+
+    virtual int row_count(const GUI::ModelIndex& = GUI::ModelIndex()) const override { return m_frames.size(); }
+    virtual int column_count(const GUI::ModelIndex& = GUI::ModelIndex()) const override { return 1; }
+
+    virtual String column_name(int) const override
+    {
+        return "";
+    }
+
+    virtual GUI::Variant data(const GUI::ModelIndex& index, Role role = Role::Display) const override;
+
+    virtual void update() override {}
+    virtual GUI::ModelIndex index(int row, int column = 0, const GUI::ModelIndex& = GUI::ModelIndex()) const override { return create_index(row, column, &m_frames.at(row)); }
+
+private:
+    struct FrameInfo {
+        String function_name;
+        u32 address_in_frame;
+    };
+
+    explicit BacktraceModel(Vector<FrameInfo>&& frames)
+        : m_frames(move(frames))
+    {
+    }
+
+    static Vector<FrameInfo> create_backtrace(const PtraceRegisters&);
+
+    Vector<FrameInfo> m_frames;
+};

DevTools/HackStudio/Debugger/DebugInfoWidget.cpp

@@ -25,28 +25,31 @@
  */
 
 #include "DebugInfoWidget.h"
+#include "BacktraceModel.h"
 #include "Debugger.h"
 #include "VariablesModel.h"
 #include <AK/StringBuilder.h>
 #include <LibGUI/BoxLayout.h>
+#include <LibGUI/ListView.h>
 #include <LibGUI/Model.h>
-#include <LibGUI/TableView.h>
+#include <LibGUI/Splitter.h>
 #include <LibGUI/TreeView.h>
 
 DebugInfoWidget::DebugInfoWidget()
 {
     set_layout<GUI::HorizontalBoxLayout>();
-    m_info_view = add<GUI::TreeView>();
-    m_backtrace_view = add<GUI::TableView>();
+    auto& splitter = add<GUI::HorizontalSplitter>();
+    m_backtrace_view = splitter.add<GUI::ListView>();
+    m_variables_view = splitter.add<GUI::TreeView>();
 }
 
 void DebugInfoWidget::update_state(const PtraceRegisters& regs)
 {
-    auto model = VariablesModel::create(regs);
-    m_info_view->set_model(model);
+    m_variables_view->set_model(VariablesModel::create(regs));
+    m_backtrace_view->set_model(BacktraceModel::create(regs));
 }
 
 void DebugInfoWidget::program_stopped()
 {
-    m_info_view->set_model({});
+    m_variables_view->set_model({});
 }

DevTools/HackStudio/Debugger/DebugInfoWidget.h

@@ -27,6 +27,7 @@
 #pragma once
 
 #include "Debugger.h"
+#include "LibGUI/ListView.h"
 #include <AK/NonnullOwnPtr.h>
 #include <LibGUI/Model.h>
 #include <LibGUI/Widget.h>
@@ -43,6 +44,6 @@ public:
 private:
     explicit DebugInfoWidget();
 
-    RefPtr<GUI::TreeView> m_info_view;
-    RefPtr<GUI::TableView> m_backtrace_view;
+    RefPtr<GUI::TreeView> m_variables_view;
+    RefPtr<GUI::ListView> m_backtrace_view;
 };

DevTools/HackStudio/Makefile

@@ -16,7 +16,8 @@ OBJS = \
     main.o \
     Debugger/DebugInfoWidget.o \
     Debugger/Debugger.o \
-    Debugger/VariablesModel.o
+    Debugger/VariablesModel.o \
+    Debugger/BacktraceModel.o
 
 PROGRAM = HackStudio
 

Libraries/LibDebug/DebugInfo.cpp

@@ -212,3 +212,13 @@ NonnullOwnPtr<DebugInfo::VariableInfo> DebugInfo::create_variable_info(const Dwa
 
     return variable_info;
 }
+
+String DebugInfo::name_of_containing_function(u32 address) const
+{
+    for (const auto& scope : m_scopes) {
+        if (!scope.is_function || address < scope.address_low || address >= scope.address_high)
+            continue;
+        return scope.name;
+    }
+    return {};
+}

Libraries/LibDebug/DebugInfo.h

@@ -93,6 +93,8 @@ public:
         }
     }
 
+    String name_of_containing_function(u32 address) const;
+
 private:
     void prepare_variable_scopes();
     void prepare_lines();