Merge pull request #36752 from RandomShaper/rework_semaphore

Drop old semaphore implementation

12 files changed, 59 insertions, 125 deletions

diff --git a/core/bind/core_bind.cpp b/core/bind/core_bind.cpp
index 264d8d415c..bfe07d61c5 100644
--- a/core/bind/core_bind.cpp
+++ b/core/bind/core_bind.cpp
@@ -2576,30 +2576,26 @@ void _Marshalls::_bind_methods() {
 
 ////////////////
 
-Error _Semaphore::wait() {
+void _Semaphore::wait() {
 
-	return semaphore->wait();
+	semaphore.wait();
 }
 
-Error _Semaphore::post() {
+Error _Semaphore::try_wait() {
 
-	return semaphore->post();
+	return semaphore.try_wait() ? OK : ERR_BUSY;
 }
 
-void _Semaphore::_bind_methods() {
+void _Semaphore::post() {
 
-	ClassDB::bind_method(D_METHOD("wait"), &_Semaphore::wait);
-	ClassDB::bind_method(D_METHOD("post"), &_Semaphore::post);
+	semaphore.post();
 }
 
-_Semaphore::_Semaphore() {
-
-	semaphore = SemaphoreOld::create();
-}
-
-_Semaphore::~_Semaphore() {
+void _Semaphore::_bind_methods() {
 
-	memdelete(semaphore);
+	ClassDB::bind_method(D_METHOD("wait"), &_Semaphore::wait);
+	ClassDB::bind_method(D_METHOD("try_wait"), &_Semaphore::try_wait);
+	ClassDB::bind_method(D_METHOD("post"), &_Semaphore::post);
 }
 
 ///////////////
diff --git a/core/bind/core_bind.h b/core/bind/core_bind.h
index e7850de744..fc6419b7d8 100644
--- a/core/bind/core_bind.h
+++ b/core/bind/core_bind.h
@@ -635,16 +635,14 @@ public:
 class _Semaphore : public Reference {
 
 	GDCLASS(_Semaphore, Reference);
-	SemaphoreOld *semaphore;
+	Semaphore semaphore;
 
 	static void _bind_methods();
 
 public:
-	Error wait();
-	Error post();
-
-	_Semaphore();
-	~_Semaphore();
+	void wait();
+	Error try_wait();
+	void post();
 };
 
 class _Thread : public Reference {
diff --git a/core/command_queue_mt.cpp b/core/command_queue_mt.cpp
index b88f773ed8..85e8a847a0 100644
--- a/core/command_queue_mt.cpp
+++ b/core/command_queue_mt.cpp
@@ -108,11 +108,10 @@ CommandQueueMT::CommandQueueMT(bool p_sync) {
 
 	for (int i = 0; i < SYNC_SEMAPHORES; i++) {
 
-		sync_sems[i].sem = SemaphoreOld::create();
 		sync_sems[i].in_use = false;
 	}
 	if (p_sync)
-		sync = SemaphoreOld::create();
+		sync = memnew(Semaphore);
 	else
 		sync = NULL;
 }
@@ -121,9 +120,5 @@ CommandQueueMT::~CommandQueueMT() {
 
 	if (sync)
 		memdelete(sync);
-	for (int i = 0; i < SYNC_SEMAPHORES; i++) {
-
-		memdelete(sync_sems[i].sem);
-	}
 	memfree(command_mem);
 }
diff --git a/core/command_queue_mt.h b/core/command_queue_mt.h
index 7407557e7e..90231546ef 100644
--- a/core/command_queue_mt.h
+++ b/core/command_queue_mt.h
@@ -270,7 +270,7 @@
 		cmd->sync_sem = ss;                                                                    \
 		unlock();                                                                              \
 		if (sync) sync->post();                                                                \
-		ss->sem->wait();                                                                       \
+		ss->sem.wait();                                                                        \
 		ss->in_use = false;                                                                    \
 	}
 
@@ -287,7 +287,7 @@
 		cmd->sync_sem = ss;                                                           \
 		unlock();                                                                     \
 		if (sync) sync->post();                                                       \
-		ss->sem->wait();                                                              \
+		ss->sem.wait();                                                               \
 		ss->in_use = false;                                                           \
 	}
 
@@ -297,7 +297,7 @@ class CommandQueueMT {
 
 	struct SyncSemaphore {
 
-		SemaphoreOld *sem;
+		Semaphore sem;
 		bool in_use;
 	};
 
@@ -313,7 +313,7 @@ class CommandQueueMT {
 		SyncSemaphore *sync_sem;
 
 		virtual void post() {
-			sync_sem->sem->post();
+			sync_sem->sem.post();
 		}
 	};
 
@@ -342,7 +342,7 @@ class CommandQueueMT {
 	uint32_t dealloc_ptr;
 	SyncSemaphore sync_sems[SYNC_SEMAPHORES];
 	Mutex mutex;
-	SemaphoreOld *sync;
+	Semaphore *sync;
 
 	template <class T>
 	T *allocate() {
diff --git a/core/io/file_access_network.cpp b/core/io/file_access_network.cpp
index 7f1eb6fd90..370dd8f982 100644
--- a/core/io/file_access_network.cpp
+++ b/core/io/file_access_network.cpp
@@ -88,9 +88,7 @@ void FileAccessNetworkClient::_thread_func() {
 	while (!quit) {
 
 		DEBUG_PRINT("SEM WAIT - " + itos(sem->get()));
-		Error err = sem->wait();
-		if (err != OK)
-			ERR_PRINT("sem->wait() failed");
+		sem.wait();
 		DEBUG_TIME("sem_unlock");
 		//DEBUG_PRINT("semwait returned "+itos(werr));
 		DEBUG_PRINT("MUTEX LOCK " + itos(lockcount));
@@ -141,7 +139,7 @@ void FileAccessNetworkClient::_thread_func() {
 					fa->_respond(len, Error(status));
 				}
 
-				fa->sem->post();
+				fa->sem.post();
 
 			} break;
 			case FileAccessNetwork::RESPONSE_DATA: {
@@ -161,14 +159,14 @@ void FileAccessNetworkClient::_thread_func() {
 
 				int status = get_32();
 				fa->exists_modtime = status != 0;
-				fa->sem->post();
+				fa->sem.post();
 
 			} break;
 			case FileAccessNetwork::RESPONSE_GET_MODTIME: {
 
 				uint64_t status = get_64();
 				fa->exists_modtime = status;
-				fa->sem->post();
+				fa->sem.post();
 
 			} break;
 		}
@@ -230,7 +228,6 @@ FileAccessNetworkClient::FileAccessNetworkClient() {
 	singleton = this;
 	last_id = 0;
 	client.instance();
-	sem = SemaphoreOld::create();
 	lockcount = 0;
 }
 
@@ -238,12 +235,10 @@ FileAccessNetworkClient::~FileAccessNetworkClient() {
 
 	if (thread) {
 		quit = true;
-		sem->post();
+		sem.post();
 		Thread::wait_to_finish(thread);
 		memdelete(thread);
 	}
-
-	memdelete(sem);
 }
 
 void FileAccessNetwork::_set_block(int p_offset, const Vector<uint8_t> &p_block) {
@@ -264,7 +259,7 @@ void FileAccessNetwork::_set_block(int p_offset, const Vector<uint8_t> &p_block)
 
 	if (waiting_on_page == page) {
 		waiting_on_page = -1;
-		page_sem->post();
+		page_sem.post();
 	}
 }
 
@@ -306,9 +301,9 @@ Error FileAccessNetwork::_open(const String &p_path, int p_mode_flags) {
 	nc->unlock_mutex();
 	DEBUG_PRINT("OPEN POST");
 	DEBUG_TIME("open_post");
-	nc->sem->post(); //awaiting answer
+	nc->sem.post(); //awaiting answer
 	DEBUG_PRINT("WAIT...");
-	sem->wait();
+	sem.wait();
 	DEBUG_TIME("open_end");
 	DEBUG_PRINT("WAIT ENDED...");
 
@@ -393,7 +388,7 @@ void FileAccessNetwork::_queue_page(int p_page) const {
 			pages.write[p_page].queued = true;
 		}
 		DEBUG_PRINT("QUEUE PAGE POST");
-		nc->sem->post();
+		nc->sem.post();
 		DEBUG_PRINT("queued " + itos(p_page));
 	}
 }
@@ -426,7 +421,7 @@ int FileAccessNetwork::get_buffer(uint8_t *p_dst, int p_length) const {
 				}
 				buffer_mutex.unlock();
 				DEBUG_PRINT("wait");
-				page_sem->wait();
+				page_sem.wait();
 				DEBUG_PRINT("done");
 			} else {
 
@@ -475,8 +470,8 @@ bool FileAccessNetwork::file_exists(const String &p_path) {
 	nc->client->put_data((const uint8_t *)cs.ptr(), cs.length());
 	nc->unlock_mutex();
 	DEBUG_PRINT("FILE EXISTS POST");
-	nc->sem->post();
-	sem->wait();
+	nc->sem.post();
+	sem.wait();
 
 	return exists_modtime != 0;
 }
@@ -492,8 +487,8 @@ uint64_t FileAccessNetwork::_get_modified_time(const String &p_file) {
 	nc->client->put_data((const uint8_t *)cs.ptr(), cs.length());
 	nc->unlock_mutex();
 	DEBUG_PRINT("MODTIME POST");
-	nc->sem->post();
-	sem->wait();
+	nc->sem.post();
+	sem.wait();
 
 	return exists_modtime;
 }
@@ -521,8 +516,6 @@ FileAccessNetwork::FileAccessNetwork() {
 	eof_flag = false;
 	opened = false;
 	pos = 0;
-	sem = SemaphoreOld::create();
-	page_sem = SemaphoreOld::create();
 	FileAccessNetworkClient *nc = FileAccessNetworkClient::singleton;
 	nc->lock_mutex();
 	id = nc->last_id++;
@@ -538,8 +531,6 @@ FileAccessNetwork::FileAccessNetwork() {
 FileAccessNetwork::~FileAccessNetwork() {
 
 	close();
-	memdelete(sem);
-	memdelete(page_sem);
 
 	FileAccessNetworkClient *nc = FileAccessNetworkClient::singleton;
 	nc->lock_mutex();
diff --git a/core/io/file_access_network.h b/core/io/file_access_network.h
index 38d9b8e8a6..7f664b46f7 100644
--- a/core/io/file_access_network.h
+++ b/core/io/file_access_network.h
@@ -49,7 +49,7 @@ class FileAccessNetworkClient {
 
 	List<BlockRequest> block_requests;
 
-	SemaphoreOld *sem;
+	Semaphore sem;
 	Thread *thread;
 	bool quit;
 	Mutex mutex;
@@ -85,8 +85,8 @@ public:
 
 class FileAccessNetwork : public FileAccess {
 
-	SemaphoreOld *sem;
-	SemaphoreOld *page_sem;
+	Semaphore sem;
+	Semaphore page_sem;
 	Mutex buffer_mutex;
 	bool opened;
 	size_t total_size;
diff --git a/core/io/ip.cpp b/core/io/ip.cpp
index af534e4bb7..2143b84d15 100644
--- a/core/io/ip.cpp
+++ b/core/io/ip.cpp
@@ -71,7 +71,7 @@ struct _IP_ResolverPrivate {
 	}
 
 	Mutex mutex;
-	SemaphoreOld *sem;
+	Semaphore sem;
 
 	Thread *thread;
 	//Semaphore* semaphore;
@@ -98,7 +98,7 @@ struct _IP_ResolverPrivate {
 
 		while (!ipr->thread_abort) {
 
-			ipr->sem->wait();
+			ipr->sem.wait();
 
 			MutexLock lock(ipr->mutex);
 			ipr->resolve_queues();
@@ -148,7 +148,7 @@ IP::ResolverID IP::resolve_hostname_queue_item(const String &p_hostname, IP::Typ
 		resolver->queue[id].response = IP_Address();
 		resolver->queue[id].status = IP::RESOLVER_STATUS_WAITING;
 		if (resolver->thread)
-			resolver->sem->post();
+			resolver->sem.post();
 		else
 			resolver->resolve_queues();
 	}
@@ -300,23 +300,13 @@ IP::IP() {
 
 	singleton = this;
 	resolver = memnew(_IP_ResolverPrivate);
-	resolver->sem = NULL;
 
 #ifndef NO_THREADS
 
-	resolver->sem = SemaphoreOld::create();
-	if (resolver->sem) {
-		resolver->thread_abort = false;
+	resolver->thread_abort = false;
 
-		resolver->thread = Thread::create(_IP_ResolverPrivate::_thread_function, resolver);
-
-		if (!resolver->thread)
-			memdelete(resolver->sem); //wtf
-	} else {
-		resolver->thread = NULL;
-	}
+	resolver->thread = Thread::create(_IP_ResolverPrivate::_thread_function, resolver);
 #else
-	resolver->sem = NULL;
 	resolver->thread = NULL;
 #endif
 }
@@ -326,10 +316,9 @@ IP::~IP() {
 #ifndef NO_THREADS
 	if (resolver->thread) {
 		resolver->thread_abort = true;
-		resolver->sem->post();
+		resolver->sem.post();
 		Thread::wait_to_finish(resolver->thread);
 		memdelete(resolver->thread);
-		memdelete(resolver->sem);
 	}
 
 #endif
diff --git a/core/os/mutex.h b/core/os/mutex.h
index 6cf8ee7c40..8d7b378d60 100644
--- a/core/os/mutex.h
+++ b/core/os/mutex.h
@@ -34,7 +34,7 @@
 #include "core/error_list.h"
 #include "core/typedefs.h"
 
-#if !(defined NO_THREADS)
+#if !defined(NO_THREADS)
 
 #include <mutex>
 
diff --git a/core/os/semaphore.cpp b/core/os/semaphore.cpp
index 2c20f234d0..93f1e2dff4 100644
--- a/core/os/semaphore.cpp
+++ b/core/os/semaphore.cpp
@@ -29,17 +29,3 @@
 /*************************************************************************/
 
 #include "semaphore.h"
-
-#include "core/error_macros.h"
-
-SemaphoreOld *(*SemaphoreOld::create_func)() = 0;
-
-SemaphoreOld *SemaphoreOld::create() {
-
-	ERR_FAIL_COND_V(!create_func, 0);
-
-	return create_func();
-}
-
-SemaphoreOld::~SemaphoreOld() {
-}
diff --git a/core/os/semaphore.h b/core/os/semaphore.h
index f16a15a6db..6f194d4887 100644
--- a/core/os/semaphore.h
+++ b/core/os/semaphore.h
@@ -34,30 +34,32 @@
 #include "core/error_list.h"
 #include "core/typedefs.h"
 
+#if !defined(NO_THREADS)
+
 #include <condition_variable>
 #include <mutex>
 
 class Semaphore {
 private:
-	std::mutex mutex_;
-	std::condition_variable condition_;
-	unsigned long count_ = 0; // Initialized as locked.
+	mutable std::mutex mutex_;
+	mutable std::condition_variable condition_;
+	mutable unsigned long count_ = 0; // Initialized as locked.
 
 public:
-	_ALWAYS_INLINE_ void post() {
+	_ALWAYS_INLINE_ void post() const {
 		std::lock_guard<decltype(mutex_)> lock(mutex_);
 		++count_;
 		condition_.notify_one();
 	}
 
-	_ALWAYS_INLINE_ void wait() {
+	_ALWAYS_INLINE_ void wait() const {
 		std::unique_lock<decltype(mutex_)> lock(mutex_);
 		while (!count_) // Handle spurious wake-ups.
 			condition_.wait(lock);
 		--count_;
 	}
 
-	_ALWAYS_INLINE_ bool try_wait() {
+	_ALWAYS_INLINE_ bool try_wait() const {
 		std::lock_guard<decltype(mutex_)> lock(mutex_);
 		if (count_) {
 			--count_;
@@ -67,18 +69,15 @@ public:
 	}
 };
 
-class SemaphoreOld {
-protected:
-	static SemaphoreOld *(*create_func)();
+#else
 
+class Semaphore {
 public:
-	virtual Error wait() = 0; ///< wait until semaphore has positive value, then decrement and pass
-	virtual Error post() = 0; ///< unlock the semaphore, incrementing the    value
-	virtual int get() const = 0; ///< get semaphore value
-
-	static SemaphoreOld *create(); ///< Create a mutex
-
-	virtual ~SemaphoreOld();
+	_ALWAYS_INLINE_ void post() const {}
+	_ALWAYS_INLINE_ void wait() const {}
+	_ALWAYS_INLINE_ bool try_wait() const { return true; }
 };
 
 #endif
+
+#endif
diff --git a/core/os/thread_dummy.cpp b/core/os/thread_dummy.cpp
index 097c90c1fb..9dcddcae11 100644
--- a/core/os/thread_dummy.cpp
+++ b/core/os/thread_dummy.cpp
@@ -40,14 +40,6 @@ void ThreadDummy::make_default() {
 	Thread::create_func = &ThreadDummy::create;
 };
 
-SemaphoreOld *SemaphoreDummy::create() {
-	return memnew(SemaphoreDummy);
-};
-
-void SemaphoreDummy::make_default() {
-	SemaphoreOld::create_func = &SemaphoreDummy::create;
-};
-
 RWLock *RWLockDummy::create() {
 	return memnew(RWLockDummy);
 };
diff --git a/core/os/thread_dummy.h b/core/os/thread_dummy.h
index c0976ec299..da8188f983 100644
--- a/core/os/thread_dummy.h
+++ b/core/os/thread_dummy.h
@@ -45,18 +45,6 @@ public:
 	static void make_default();
 };
 
-class SemaphoreDummy : public SemaphoreOld {
-
-	static SemaphoreOld *create();
-
-public:
-	virtual Error wait() { return OK; };
-	virtual Error post() { return OK; };
-	virtual int get() const { return 0; }; ///< get semaphore value
-
-	static void make_default();
-};
-
 class RWLockDummy : public RWLock {
 
 	static RWLock *create();