Implements UI to start debug (#1015)

gui/cpu_settings.cpp

@@ -3,14 +3,19 @@
 #include <QGridLayout>
 #include <QGroupBox>
 #include <QLabel>
+#include <QLineEdit>
+#include <QMessageBox>
+#include <QPushButton>
 #include <QSlider>
 
 CpuSettings::CpuSettings(QWidget *parent) :
-    QWidget(parent)
+    QWidget(parent),
+    m_debugAddr(nullptr)
 {
     auto layout = new QGridLayout();
 
     layout->addWidget(buildCount(), 0, 0);
+    layout->addWidget(buildDebug(), 0, 1);
     layout->setRowStretch(1, 1);
 
     setLayout(layout);
@@ -53,3 +58,50 @@ QWidget *CpuSettings::buildCount()
 
     return group;
 }
+
+QWidget *CpuSettings::buildDebug()
+{
+    auto group = new QGroupBox("Debug");
+    auto layout = new QGridLayout();
+
+    // Address label.
+    auto label = new QLabel("Listen address:");
+
+    layout->addWidget(label, 0, 0);
+
+    // Address editor.
+    m_debugAddr = new QLineEdit("127.0.0.1:1234");
+
+    label->setBuddy(m_debugAddr);
+
+    layout->addWidget(m_debugAddr, 0, 1);
+
+    // Start.
+    auto start = new QPushButton("Start");
+
+    connect(start, &QAbstractButton::clicked, [this] {
+        auto addr = m_debugAddr->text();
+
+        if (addr.isEmpty()) {
+            QMessageBox::critical(this, "Error", "Listen address cannot be empty.");
+            return;
+        }
+
+        emit debugClicked(addr);
+    });
+
+    layout->addWidget(start, 0, 2);
+
+    // Description.
+    auto desc = new QLabel(
+        "Specify a TCP address to listen for a debugger. The kernel will wait for a debugger to "
+        "connect before start.");
+
+    desc->setWordWrap(true);
+
+    layout->addWidget(desc, 1, 0, 1, -1);
+
+    group->setLayout(layout);
+
+    return group;
+}

gui/cpu_settings.hpp

@@ -2,10 +2,18 @@
 
 #include <QWidget>
 
+class QLineEdit;
+
 class CpuSettings final : public QWidget {
+    Q_OBJECT
 public:
     CpuSettings(QWidget *parent = nullptr);
     ~CpuSettings() override;
+signals:
+    void debugClicked(const QString &addr);
 private:
     QWidget *buildCount();
+    QWidget *buildDebug();
+
+    QLineEdit *m_debugAddr;
 };

gui/launch_settings.cpp

@@ -94,6 +94,10 @@ QWidget *LaunchSettings::buildSettings(GameListModel *games, QList<VkPhysicalDev
     // CPU settings.
     m_cpu = new CpuSettings();
 
+    connect(m_cpu, &CpuSettings::debugClicked, [this](const QString &addr) {
+        emit startClicked(addr);
+    });
+
     tab->addTab(m_cpu, loadIcon(":/resources/cpu-64-bit.svg", iconSize), "CPU");
 
     // Game list.
@@ -153,7 +157,7 @@ QLayout *LaunchSettings::buildActions(ProfileList *profiles)
 
     start->setIcon(loadIcon(":/resources/play.svg", start->iconSize()));
 
-    connect(start, &QAbstractButton::clicked, [this]() { emit startClicked(); });
+    connect(start, &QAbstractButton::clicked, [this]() { emit startClicked({}); });
 
     actions->addButton(start, QDialogButtonBox::AcceptRole);
 

gui/launch_settings.hpp

@@ -39,7 +39,7 @@ public:
 #endif
 signals:
     void saveClicked(Profile *p);
-    void startClicked();
+    void startClicked(const QString &debugAddr);
 private:
 #ifdef __APPLE__
     QWidget *buildSettings(GameListModel *games);

gui/main_window.cpp

@@ -341,7 +341,7 @@ void MainWindow::saveProfile(Profile *p)
     }
 }
 
-void MainWindow::startKernel()
+void MainWindow::startKernel(const QString &debugAddr)
 {
     // Get full path to kernel binary.
     std::string kernel;
@@ -387,6 +387,7 @@ void MainWindow::startKernel()
     m_main->setCurrentIndex(1);
 
     // Run.
+    auto debug = debugAddr.toStdString();
     VmmScreen screen;
     Rust<RustError> error;
     Rust<Vmm> vmm;
@@ -411,7 +412,7 @@ void MainWindow::startKernel()
         kernel.c_str(),
         &screen,
         m_launch->currentProfile(),
-        nullptr,
+        debug.empty() ? nullptr : debug.c_str(),
         MainWindow::vmmHandler,
         this,
         &error);
@@ -459,7 +460,7 @@ void MainWindow::waitingDebugger(const QString &addr)
 {
     QMessageBox::information(
         this,
-        "Action required",
+        "Debug",
         QString("The kernel are waiting for a debugger at %1.").arg(addr));
 }
 

gui/main_window.hpp

@@ -38,7 +38,7 @@ private slots:
     void reportIssue();
     void aboutObliteration();
     void saveProfile(Profile *p);
-    void startKernel();
+    void startKernel(const QString &debugAddr);
     void updateScreen();
 private:
     void waitingDebugger(const QString &addr);

gui/src/vmm/mod.rs

@@ -20,7 +20,8 @@ use std::ptr::null_mut;
 use std::sync::atomic::{AtomicBool, Ordering};
 use std::sync::mpsc::Sender;
 use std::sync::Arc;
-use std::thread::JoinHandle;
+use std::thread::{sleep, JoinHandle};
+use std::time::Duration;
 use thiserror::Error;
 
 #[cfg_attr(target_arch = "aarch64", path = "aarch64.rs")]
@@ -50,19 +51,32 @@ pub unsafe extern "C" fn vmm_run(
     // Setup debug server.
     let debug = match debug.is_null() {
         true => None,
-        false => match CStr::from_ptr(debug).to_str() {
-            Ok(addr) => match TcpListener::bind(addr) {
-                Ok(v) => Some(v),
-                Err(e) => {
-                    *err = RustError::with_source("couldn't listen for a debugger", e);
-                    return null_mut();
-                }
-            },
+        false => {
+            // Get address to listen.
+            let addr = match CStr::from_ptr(debug).to_str() {
+                Ok(v) => v,
                 Err(_) => {
                     *err = RustError::new("address to listen for a debugger is not UTF-8");
                     return null_mut();
                 }
-        },
+            };
+
+            // Setup server.
+            let sock = match TcpListener::bind(addr) {
+                Ok(v) => v,
+                Err(e) => {
+                    *err = RustError::with_source("couldn't listen for a debugger", e);
+                    return null_mut();
+                }
+            };
+
+            if let Err(e) = sock.set_nonblocking(true) {
+                *err = RustError::with_source("couldn't enable non-blocking on a debug server", e);
+                return null_mut();
+            }
+
+            Some(sock)
+        }
     };
 
     // Check if path UTF-8.
@@ -539,7 +553,21 @@ fn main_cpu<H: Hypervisor>(
         }
 
         // Wait for a debugger.
-        debug.accept().unwrap().0;
+        loop {
+            if args.shutdown.load(Ordering::Relaxed) {
+                return;
+            }
+
+            // Try accept a connection.
+            let e = match debug.accept() {
+                Ok(_) => break,
+                Err(e) => e,
+            };
+
+            assert_eq!(e.kind(), std::io::ErrorKind::WouldBlock);
+
+            sleep(Duration::from_secs(1));
+        }
     }
 
     run_cpu(cpu, args);