SVC: Implemented svcCreateSemaphore

ToDo: Implement svcReleaseSemaphore
* Some testing against hardware needed

2 files changed, 98 insertions, 0 deletions

diff --git a/src/core/hle/kernel/semaphore.cpp b/src/core/hle/kernel/semaphore.cpp
new file mode 100644
index 000000000..73ffbe3cf
--- /dev/null
+++ b/src/core/hle/kernel/semaphore.cpp
@@ -0,0 +1,76 @@
+// Copyright 2014 Citra Emulator Project
+// Licensed under GPLv2+
+// Refer to the license.txt file included.
+
+#include <map>
+#include <vector>
+
+#include "common/common.h"
+
+#include "core/hle/kernel/kernel.h"
+#include "core/hle/kernel/semaphore.h"
+#include "core/hle/kernel/thread.h"
+
+namespace Kernel {
+
+class Semaphore : public Object {
+public:
+    std::string GetTypeName() const override { return "Semaphore"; }
+    std::string GetName() const override { return name; }
+
+    static Kernel::HandleType GetStaticHandleType() { return Kernel::HandleType::Semaphore; }
+    Kernel::HandleType GetHandleType() const override { return Kernel::HandleType::Semaphore; }
+
+    u32 initial_count;                          ///< Number of reserved entries
+    u32 max_count;                              ///< Maximum number of simultaneous holders the semaphore can have
+    u32 current_usage;                          ///< Number of currently used entries in the semaphore
+    std::vector<Handle> waiting_threads;        ///< Threads that are waiting for the semaphore
+    std::string name;                           ///< Name of semaphore (optional)
+
+    ResultVal<bool> SyncRequest() override {
+        // TODO(Subv): ImplementMe
+        return MakeResult<bool>(false);
+    }
+
+    ResultVal<bool> WaitSynchronization() override {
+        bool wait = current_usage == max_count;
+
+        if (wait) {
+            Kernel::WaitCurrentThread(WAITTYPE_SEMA, GetHandle());
+            waiting_threads.push_back(GetCurrentThreadHandle());
+        } else {
+            ++current_usage;
+        }
+
+        return MakeResult<bool>(wait);
+    }
+};
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+
+/**
+ * Creates a semaphore
+ * @param handle Reference to handle for the newly created semaphore
+ * @param initial_count initial amount of times the semaphore is held
+ * @param max_count maximum number of holders the semaphore can have
+ * @param name Optional name of semaphore
+ * @return Pointer to new Semaphore object
+ */
+Semaphore* CreateSemaphore(Handle& handle, u32 initial_count, u32 max_count, const std::string& name) {
+    Semaphore* semaphore = new Semaphore;
+    handle = Kernel::g_object_pool.Create(semaphore);
+
+    semaphore->initial_count = semaphore->current_usage = initial_count;
+    semaphore->max_count = max_count;
+    semaphore->name = name;
+
+    return semaphore;
+}
+
+Handle CreateSemaphore(u32 initial_count, u32 max_count, const std::string& name) {
+    Handle handle;
+    Semaphore* semaphore = CreateSemaphore(handle, initial_count, max_count, name);
+    return handle;
+}
+
+} // namespace
diff --git a/src/core/hle/kernel/semaphore.h b/src/core/hle/kernel/semaphore.h
new file mode 100644
index 000000000..6a686db2e
--- /dev/null
+++ b/src/core/hle/kernel/semaphore.h
@@ -0,0 +1,22 @@
+// Copyright 2014 Citra Emulator Project
+// Licensed under GPLv2+
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include "common/common_types.h"
+
+#include "core/hle/kernel/kernel.h"
+
+namespace Kernel {
+
+/**
+ * Creates a semaphore
+ * @param initial_count number of reserved entries in the semaphore
+ * @param max_count maximum number of holders the semaphore can have
+  * @param name Optional name of semaphore
+ * @return Handle to newly created object
+ */
+Handle CreateSemaphore(u32 initial_count, u32 max_count, const std::string& name = "Unknown");
+
+} // namespace