LibC/Kernel: Add support for detached pthreads

kernel/include/kernel/Process.h

@@ -214,6 +214,7 @@ namespace Kernel
 		BAN::ErrorOr<long> sys_pthread_join(pthread_t thread, void** value);
 		BAN::ErrorOr<long> sys_pthread_self();
 		BAN::ErrorOr<long> sys_pthread_kill(pthread_t thread, int signal);
+		BAN::ErrorOr<long> sys_pthread_detach(pthread_t thread);
 
 		BAN::ErrorOr<long> sys_clock_gettime(clockid_t, timespec*);
 

kernel/include/kernel/Thread.h

@@ -117,6 +117,9 @@ namespace Kernel
 		const Process& process() const;
 		bool has_process() const { return m_process; }
 
+		void detach() { m_is_detached = true; }
+		bool is_detached() const { return m_is_detached; }
+
 		bool is_userspace() const { return m_is_userspace; }
 
 		uint64_t cpu_time_ns() const;
@@ -176,6 +179,7 @@ namespace Kernel
 		State                      m_state                { State::NotStarted };
 		Process*                   m_process              { nullptr };
 		bool                       m_is_userspace         { false };
+		BAN::Atomic<bool>          m_is_detached          { false };
 		bool                       m_delete_process       { false };
 
 		vaddr_t                    m_fsbase               { 0 };

kernel/kernel/Process.cpp

@@ -3334,20 +3334,24 @@ namespace Kernel
 		if (m_threads.size() == 1)
 			return sys_exit(0);
 
-		TRY(m_exited_pthreads.emplace_back(Thread::current().tid(), value));
+		auto& thread = Thread::current();
+		if (!thread.is_detached())
+		{
+			TRY(m_exited_pthreads.emplace_back(thread.tid(), value));
+			m_pthread_exit_blocker.unblock();
+		}
 
-		m_pthread_exit_blocker.unblock();
 		m_process_lock.unlock();
-		Thread::current().on_exit();
+		thread.on_exit();
 
 		ASSERT_NOT_REACHED();
 	}
 
-	BAN::ErrorOr<long> Process::sys_pthread_join(pthread_t thread, void** user_value)
+	BAN::ErrorOr<long> Process::sys_pthread_join(pthread_t tid, void** user_value)
 	{
 		LockGuard _(m_process_lock);
 
-		if (thread == Thread::current().tid())
+		if (tid == Thread::current().tid())
 			return BAN::Error::from_errno(EINVAL);
 
 		const auto check_thread =
@@ -3355,13 +3359,10 @@ namespace Kernel
 			{
 				for (size_t i = 0; i < m_exited_pthreads.size(); i++)
 				{
-					if (m_exited_pthreads[i].thread != thread)
+					if (m_exited_pthreads[i].thread != tid)
 						continue;
-
 					void* ret = m_exited_pthreads[i].value;
-
 					m_exited_pthreads.remove(i);
-
 					return ret;
 				}
 
@@ -3379,10 +3380,18 @@ namespace Kernel
 
 			{
 				bool found = false;
-				for (auto* _thread : m_threads)
-					if (_thread->tid() == thread)
-						found = true;
+				bool joinable = false;
+				for (auto* thread : m_threads)
+				{
+					if (thread->tid() != tid)
+						continue;
+					found = true;
+					joinable = !thread->is_detached();
+					break;
+				}
 				if (!found)
+					return BAN::Error::from_errno(ESRCH);
+				if (!joinable)
 					return BAN::Error::from_errno(EINVAL);
 			}
 
@@ -3425,6 +3434,24 @@ namespace Kernel
 		return BAN::Error::from_errno(ESRCH);
 	}
 
+	BAN::ErrorOr<long> Process::sys_pthread_detach(pthread_t tid)
+	{
+		LockGuard _(m_process_lock);
+
+		for (auto* thread : m_threads)
+		{
+			if (thread->tid() != tid)
+				continue;
+			if (thread->is_detached())
+				return BAN::Error::from_errno(EINVAL);
+			thread->detach();
+			m_pthread_exit_blocker.unblock();
+			return 0;
+		}
+
+		return BAN::Error::from_errno(ESRCH);
+	}
+
 	BAN::ErrorOr<long> Process::sys_setuid(uid_t uid)
 	{
 		if (uid < 0 || uid >= 1'000'000'000)

userspace/libraries/LibC/include/sys/syscall.h

@@ -105,6 +105,7 @@ __BEGIN_DECLS
 	O(SYS_PTHREAD_JOIN,		pthread_join)	\
 	O(SYS_PTHREAD_SELF,		pthread_self)	\
 	O(SYS_PTHREAD_KILL,		pthread_kill)	\
+	O(SYS_PTHREAD_DETACH,   pthread_detach) \
 	O(SYS_EPOLL_CREATE1,	epoll_create1)	\
 	O(SYS_EPOLL_CTL,		epoll_ctl)		\
 	O(SYS_EPOLL_PWAIT2,		epoll_pwait2)	\

userspace/libraries/LibC/pthread.cpp

@@ -18,6 +18,7 @@
 struct pthread_trampoline_info_t
 {
 	struct uthread* uthread;
+	bool detached;
 	void* (*start_routine)(void*);
 	void* arg;
 };
@@ -71,6 +72,8 @@ extern "C" void _pthread_trampoline_cpp(void* arg)
 #endif
 	free(arg);
 	signal(SIGCANCEL, &_pthread_cancel_handler);
+	if (info.detached)
+		pthread_detach(info.uthread->id);
 	pthread_exit(info.start_routine(info.arg));
 	ASSERT_NOT_REACHED();
 }
@@ -257,8 +260,6 @@ int pthread_attr_setdetachstate(pthread_attr_t* attr, int detachstate)
 	switch (detachstate)
 	{
 		case PTHREAD_CREATE_DETACHED:
-			dwarnln("TODO: pthread_attr_setdetachstate");
-			return ENOTSUP;
 		case PTHREAD_CREATE_JOINABLE:
 			attr->detachstate = detachstate;
 			return 0;
@@ -386,6 +387,7 @@ int pthread_create(pthread_t* __restrict thread_id, const pthread_attr_t* __rest
 
 	*info = {
 		.uthread = nullptr,
+		.detached = attr ? (attr->detachstate == PTHREAD_CREATE_DETACHED) : false,
 		.start_routine = start_routine,
 		.arg = arg,
 	};
@@ -448,9 +450,7 @@ pthread_create_error:
 
 int pthread_detach(pthread_t thread)
 {
-	(void)thread;
-	dwarnln("TODO: pthread_detach");
-	return ENOTSUP;
+	return syscall(SYS_PTHREAD_DETACH, thread);
 }
 
 void pthread_exit(void* value_ptr)