Fix crashes when libobjcdarwin is unloaded

Author: LubosD

src/libdyld/MachOMgr.cpp

@@ -88,6 +88,21 @@ void MachOMgr::registerUnloadHook(LoaderHookFunc* func)
 	m_unloadHooks.insert(func);
 }
 
+void MachOMgr::deregisterLoadHook(LoaderHookFunc* func)
+{
+	Darling::RWMutexWriteLock l(m_lock);
+	
+	m_loadHooks.erase(func);
+}
+
+void MachOMgr::deregisterUnloadHook(LoaderHookFunc* func)
+{
+	Darling::RWMutexWriteLock l(m_lock);
+	
+	m_unloadHooks.erase(func);
+}
+
+
 void MachOMgr::add(MachOObject* obj, bool mainModule)
 {
 	Darling::RWMutexWriteLock l(m_lock);

src/libdyld/MachOMgr.h

@@ -55,6 +55,9 @@ class MachOMgr
 	void registerLoadHook(LoaderHookFunc* func);
 	void registerUnloadHook(LoaderHookFunc* func);
 
+	void deregisterLoadHook(LoaderHookFunc* func);
+	void deregisterUnloadHook(LoaderHookFunc* func);
+	
 	// DYLD_BIND_AT_LAUNCH
 	inline void setBindAtLaunch(bool bindAtLaunch) { m_bindAtLaunch = bindAtLaunch; }
 	inline bool bindAtLaunch() const { return m_bindAtLaunch || useTrampolines(); }

src/libdyld/dl_public.cpp

@@ -18,7 +18,7 @@
 static thread_local char g_lastError[1024];
 static thread_local bool g_lastErrorRead = false;
 
-static std::set<Darling::DlsymHookFunc> g_dlsymHooks;
+static std::set<Darling::DlsymHookFunc>* g_dlsymHooks = new std::set<Darling::DlsymHookFunc>;
 
 using namespace Darling;
 
@@ -116,7 +116,7 @@ static std::string processSymbolViaHooks(const std::string& symbol)
 
 	strcpy(translated, symbol.c_str());
 
-	for (Darling::DlsymHookFunc hook : g_dlsymHooks)
+	for (Darling::DlsymHookFunc hook : *g_dlsymHooks)
 	{
 		if (hook(translated))
 			return translated;
@@ -268,11 +268,11 @@ const char* NSLibraryNameForModule(NSModule m)
 
 void Darling::registerDlsymHook(DlsymHookFunc func)
 {
-	g_dlsymHooks.insert(func);
+	g_dlsymHooks->insert(func);
 }
 
 void Darling::deregisterDlsymHook(DlsymHookFunc func)
 {
-	//g_dlsymHooks.erase(func);
+	g_dlsymHooks->erase(func);
 }
 

src/libdyld/dyld_public.cpp

@@ -79,6 +79,16 @@ void _dyld_register_func_for_remove_image(MachOMgr::LoaderHookFunc* func)
 	MachOMgr::instance()->registerUnloadHook(func);
 }
 
+void _dyld_deregister_func_for_add_image(MachOMgr::LoaderHookFunc* func)
+{
+	MachOMgr::instance()->deregisterLoadHook(func);
+}
+
+void _dyld_deregister_func_for_remove_image(MachOMgr::LoaderHookFunc* func)
+{
+	MachOMgr::instance()->deregisterUnloadHook(func);
+}
+
 
 const char* dyld_image_path_containing_address(const void* addr)
 {

src/libdyld/dyld_public.h

@@ -49,6 +49,8 @@ char* getsectdata(const struct mach_header* header, const char* segname, const c
 
 void _dyld_register_func_for_add_image(Darling::MachOMgr::LoaderHookFunc* func);
 void _dyld_register_func_for_remove_image(Darling::MachOMgr::LoaderHookFunc* func);
+void _dyld_deregister_func_for_add_image(Darling::MachOMgr::LoaderHookFunc* func);
+void _dyld_deregister_func_for_remove_image(Darling::MachOMgr::LoaderHookFunc* func);
 
 void __dyld_make_delayed_module_initializer_calls();
 void __dyld_mod_term_funcs();

src/libobjcdarwin/ClassRegister.cpp

@@ -49,6 +49,12 @@ __attribute__((constructor))
 	//std::cout << "Done registering\n";
 }
 
+__attribute__((destructor))
+	void DeregisterHooks()
+{
+	_dyld_deregister_func_for_add_image(ProcessImageLoad);
+	_dyld_deregister_func_for_remove_image(ProcessImageUnload);
+}
 
 void ProcessImageLoad(const struct mach_header* mh, intptr_t slide)
 {