git subrepo clone https://github.com/Atmosphere-NX/Atmosphere-libs libraries

subrepo:
  subdir:   "libraries"
  merged:   "07af583b"
upstream:
  origin:   "https://github.com/Atmosphere-NX/Atmosphere-libs"
  branch:   "master"
  commit:   "07af583b"
git-subrepo:
  version:  "0.4.0"
  origin:   "https://github.com/ingydotnet/git-subrepo"
  commit:   "5d6aba9"

libraries/libstratosphere/include/stratosphere/os/os_message_queue.hpp

@@ -0,0 +1,89 @@
+/*
+ * Copyright (c) 2018-2019 Atmosphère-NX
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+#include "os_mutex.hpp"
+#include "os_condvar.hpp"
+
+namespace ams::os {
+
+    namespace impl {
+
+        class WaitableObjectList;
+
+        template<MessageQueueWaitKind WaitKind>
+        class WaitableHolderOfMessageQueue;
+
+    }
+
+    class MessageQueue {
+        template<MessageQueueWaitKind WaitKind>
+        friend class impl::WaitableHolderOfMessageQueue;
+        NON_COPYABLE(MessageQueue);
+        NON_MOVEABLE(MessageQueue);
+        private:
+            util::TypedStorage<impl::WaitableObjectList, sizeof(util::IntrusiveListNode), alignof(util::IntrusiveListNode)> waitlist_not_empty;
+            util::TypedStorage<impl::WaitableObjectList, sizeof(util::IntrusiveListNode), alignof(util::IntrusiveListNode)> waitlist_not_full;
+            Mutex queue_lock;
+            ConditionVariable cv_not_full;
+            ConditionVariable cv_not_empty;
+            std::unique_ptr<uintptr_t[]> buffer;
+            size_t capacity;
+
+            size_t count;
+            size_t offset;
+        private:
+            constexpr inline bool IsFull() const {
+                return this->count >= this->capacity;
+            }
+
+            constexpr inline bool IsEmpty() const {
+                return this->count == 0;
+            }
+
+            void SendInternal(uintptr_t data);
+            void SendNextInternal(uintptr_t data);
+            uintptr_t ReceiveInternal();
+            uintptr_t PeekInternal();
+        public:
+            MessageQueue(std::unique_ptr<uintptr_t[]> buf, size_t c);
+            ~MessageQueue();
+
+            /* For convenience. */
+            MessageQueue(size_t c) : MessageQueue(std::make_unique<uintptr_t[]>(c), c) { /* ... */ }
+
+            /* Sending (FIFO functionality) */
+            void Send(uintptr_t data);
+            bool TrySend(uintptr_t data);
+            bool TimedSend(uintptr_t data, u64 timeout);
+
+            /* Sending (LIFO functionality) */
+            void SendNext(uintptr_t data);
+            bool TrySendNext(uintptr_t data);
+            bool TimedSendNext(uintptr_t data, u64 timeout);
+
+            /* Receive functionality */
+            void Receive(uintptr_t *out);
+            bool TryReceive(uintptr_t *out);
+            bool TimedReceive(uintptr_t *out, u64 timeout);
+
+            /* Peek functionality */
+            void Peek(uintptr_t *out);
+            bool TryPeek(uintptr_t *out);
+            bool TimedPeek(uintptr_t *out, u64 timeout);
+    };
+
+}