Merge pull request #1450 from contour-terminal/fix/race-on-mouseMove

Fix thread safety issue on mouse move event handling

metainfo.xml

@@ -114,6 +114,7 @@
           <li>Fixes `scripts/install-deps.sh` for openSuSE (Tumbleweed) to install the correct dependencies.</li>
           <li>Fixes missing dependencies for release .deb packages (#1397).</li>
           <li>Fixes legacy keyboard input protocol not reporting non-Alt modifier (#1411).</li>
+          <li>Fixes thread safety issue on mouse move event handling (#1444).</li>
           <li>Digitally sign MacOS release binaries using a valid Apple ID.</li>
           <li>Add support for authenticating to SSH servers with a private key without a password and without requesting for one - also allow password retry (#1425).</li>
           <li>Default history limit is now 1000 lines rather than 0 lines.</li>

src/contour/TerminalSession.cpp

@@ -14,6 +14,7 @@
 
 #include <crispy/StackTrace.h>
 #include <crispy/assert.h>
+#include <crispy/utils.h>
 
 #include <QtCore/QDebug>
 #include <QtCore/QFileInfo>
@@ -827,7 +828,9 @@ void TerminalSession::sendMousePressEvent(Modifiers modifiers,
 
     terminal().tick(steady_clock::now());
 
-    if (terminal().sendMousePressEvent(modifiers, button, pixelPosition, uiHandledHint))
+    if (crispy::locked(_terminal, [&]() {
+            return _terminal.sendMousePressEvent(modifiers, button, pixelPosition, uiHandledHint);
+        }))
         return;
 
     auto const sanitizedModifier = modifiers.contains(_config.bypassMouseProtocolModifiers)
@@ -852,7 +855,8 @@ void TerminalSession::sendMouseMoveEvent(vtbackend::Modifiers modifiers,
     terminal().tick(steady_clock::now());
 
     auto constexpr UiHandledHint = false;
-    terminal().sendMouseMoveEvent(modifiers, pos, pixelPosition, UiHandledHint);
+    crispy::locked(_terminal,
+                   [&]() { _terminal.sendMouseMoveEvent(modifiers, pos, pixelPosition, UiHandledHint); });
 
     if (pos != _currentMousePosition)
     {
@@ -871,8 +875,10 @@ void TerminalSession::sendMouseReleaseEvent(Modifiers modifiers,
 {
     terminal().tick(steady_clock::now());
 
-    auto const uiHandledHint = false;
-    terminal().sendMouseReleaseEvent(modifiers, button, pixelPosition, uiHandledHint);
+    crispy::locked(_terminal, [&]() {
+        auto const uiHandledHint = false;
+        _terminal.sendMouseReleaseEvent(modifiers, button, pixelPosition, uiHandledHint);
+    });
     scheduleRedraw();
 }
 

src/crispy/defines.h

@@ -15,6 +15,7 @@
 
 #if (defined(__cpp_concepts) && __cpp_concepts >= 201500L) \
     && (defined(__cpp_lib_concepts) && __cpp_lib_concepts >= 202002L)
+    #define CRISPY_CONCEPTS_SUPPORTED
     #define CRISPY_REQUIRES(x) requires x
 #else
     #define CRISPY_REQUIRES(x) /*!*/

src/crispy/utils.h

@@ -1,5 +1,6 @@
 #pragma once
 
+#include <crispy/defines.h>
 #include <crispy/escape.h>
 
 #include <fmt/format.h>
@@ -11,13 +12,18 @@
 #include <filesystem>
 #include <fstream>
 #include <functional>
+#include <mutex>
 #include <optional>
 #include <sstream>
 #include <string>
 #include <string_view>
 #include <unordered_map>
 #include <vector>
 
+#if defined(CRISPY_CONCEPTS_SUPPORTED)
+    #include <concepts>
+#endif
+
 namespace crispy
 {
 
@@ -297,6 +303,27 @@ class finally // NOLINT(readability-identifier-naming)
     std::function<void()> _hook {};
 };
 
+#if defined(CRISPY_CONCEPTS_SUPPORTED)
+
+// clang-format off
+template <typename T>
+concept LockableConcept = requires(T t)
+{
+    { t.lock() } -> std::same_as<void>;
+    { t.unlock() } -> std::same_as<void>;
+};
+// clang-format on
+
+#endif
+
+template <typename L, typename F>
+CRISPY_REQUIRES(LockableConcept<L>)
+auto locked(L& lockable, F const& f)
+{
+    auto const _ = std::scoped_lock { lockable };
+    return f();
+}
+
 inline std::optional<unsigned> fromHexDigit(char value)
 {
     if ('0' <= value && value <= '9')