1 files changed, 65 insertions, 0 deletions

diff --git a/src/core/hle/kernel/condition_variable.cpp b/src/core/hle/kernel/condition_variable.cpp
new file mode 100644
index 000000000..8908aeeb6
--- /dev/null
+++ b/src/core/hle/kernel/condition_variable.cpp
@@ -0,0 +1,65 @@
+// Copyright 2018 Yuzu Emulator Team
+// Licensed under GPLv2 or any later version
+// Refer to the license.txt file included.
+
+#include "common/assert.h"
+#include "core/hle/kernel/condition_variable.h"
+#include "core/hle/kernel/errors.h"
+#include "core/hle/kernel/kernel.h"
+#include "core/hle/kernel/object_address_table.h"
+#include "core/hle/kernel/thread.h"
+
+namespace Kernel {
+
+ConditionVariable::ConditionVariable() {}
+ConditionVariable::~ConditionVariable() {}
+
+ResultVal<SharedPtr<ConditionVariable>> ConditionVariable::Create(VAddr guest_addr,
+                                                                  VAddr mutex_addr,
+                                                                  std::string name) {
+    SharedPtr<ConditionVariable> condition_variable(new ConditionVariable);
+
+    condition_variable->name = std::move(name);
+    condition_variable->guest_addr = guest_addr;
+    condition_variable->mutex_addr = mutex_addr;
+
+    // Condition variables are referenced by guest address, so track this in the kernel
+    g_object_address_table.Insert(guest_addr, condition_variable);
+
+    return MakeResult<SharedPtr<ConditionVariable>>(std::move(condition_variable));
+}
+
+bool ConditionVariable::ShouldWait(Thread* thread) const {
+    return GetAvailableCount() <= 0;
+}
+
+void ConditionVariable::Acquire(Thread* thread) {
+    if (GetAvailableCount() <= 0)
+        return;
+
+    SetAvailableCount(GetAvailableCount() - 1);
+}
+
+ResultCode ConditionVariable::Release(s32 target) {
+    if (target == -1) {
+        // When -1, wake up all waiting threads
+        SetAvailableCount(GetWaitingThreads().size());
+        WakeupAllWaitingThreads();
+    } else {
+        // Otherwise, wake up just a single thread
+        SetAvailableCount(target);
+        WakeupWaitingThread(GetHighestPriorityReadyThread());
+    }
+
+    return RESULT_SUCCESS;
+}
+
+s32 ConditionVariable::GetAvailableCount() const {
+    return Memory::Read32(guest_addr);
+}
+
+void ConditionVariable::SetAvailableCount(s32 value) const {
+    Memory::Write32(guest_addr, value);
+}
+
+} // namespace Kernel