add debug ld hook

src/core/CMakeLists.txt

@@ -43,6 +43,7 @@ qt_add_library(quickshell-core STATIC
 	toolsupport.cpp
 	streamreader.cpp
 	debuginfo.cpp
+	hook.cpp
 )
 
 qt_add_qml_module(quickshell-core

src/core/hook.cpp

@@ -0,0 +1,86 @@
+#include <dlfcn.h>
+
+#include <array>
+#include <cstdlib>
+#include <string>
+
+#include <cpptrace/basic.hpp>
+
+#include <QCoreApplication>
+#include <QEvent>
+#include <QLoggingCategory>
+#include <QMetaObject>
+#include <QObject>
+
+__attribute__((constructor)) static void initHook() {
+	unsetenv("LD_PRELOAD");
+}
+
+Q_LOGGING_CATEGORY(logDestructors, "quickshell.destructors");
+Q_LOGGING_CATEGORY(logPostEvent, "quickshell.postEvent");
+
+static std::string traceAddrs() {
+	std::array<cpptrace::frame_ptr, 64> frames{};
+	auto count = cpptrace::safe_generate_raw_trace(frames.data(), frames.size(), 1);
+	std::string result;
+	for (size_t i = 0; i < count; i++) {
+		if (i > 0) result += ',';
+		char buf[20];
+		snprintf(buf, sizeof(buf), "%p", reinterpret_cast<void*>(frames[i]));
+		result += buf;
+	}
+	return result;
+}
+
+using VoidMemberFn = void (*)(QObject*);
+
+static VoidMemberFn realD2() {
+	static auto fn = reinterpret_cast<VoidMemberFn>(dlsym(RTLD_NEXT, "_ZN7QObjectD2Ev"));
+	return fn;
+}
+
+static VoidMemberFn realDeleteLater() {
+	static auto fn =
+	    reinterpret_cast<VoidMemberFn>(dlsym(RTLD_NEXT, "_ZN7QObject11deleteLaterEv"));
+	return fn;
+}
+
+using PostEventFn = void (*)(QObject*, QEvent*, int);
+
+static PostEventFn realPostEvent() {
+	static auto fn = reinterpret_cast<PostEventFn>(
+	    dlsym(RTLD_NEXT, "_ZN16QCoreApplication9postEventEP7QObjectP6QEventi")
+	);
+	return fn;
+}
+
+extern "C" {
+
+void _ZN7QObjectD2Ev(QObject* self) {
+	const auto* meta = self->metaObject();
+	auto trace = traceAddrs();
+	qCDebug(logDestructors, "~QObject %p %s\n%s", static_cast<void*>(self), meta->className(), trace.c_str());
+	realD2()(self);
+}
+
+void _ZN7QObject11deleteLaterEv(QObject* self) {
+	const auto* meta = self->metaObject();
+	auto trace = traceAddrs();
+	qCDebug(logDestructors, "deleteLater %p %s\n%s", static_cast<void*>(self), meta->className(), trace.c_str());
+	realDeleteLater()(self);
+}
+
+void _ZN16QCoreApplication9postEventEP7QObjectP6QEventi(
+    QObject* receiver,
+    QEvent* event,
+    int priority
+) {
+	//if (event->type() == QEvent::User + 1) {
+		const auto* meta = receiver->metaObject();
+		auto trace = traceAddrs();
+		qCDebug(logPostEvent, "%p %d %s\n%s", static_cast<void*>(receiver), event->type(), meta->className(), trace.c_str());
+	//}
+	realPostEvent()(receiver, event, priority);
+}
+
+} // extern "C"