5 files changed, 117 insertions, 1 deletions

diff --git a/src/core/CMakeLists.txt b/src/core/CMakeLists.txt
index 8f6792791..567d7454e 100644
--- a/src/core/CMakeLists.txt
+++ b/src/core/CMakeLists.txt
@@ -28,6 +28,7 @@ set(SRCS
             hle/kernel/event.cpp
             hle/kernel/kernel.cpp
             hle/kernel/mutex.cpp
+            hle/kernel/semaphore.cpp
             hle/kernel/shared_memory.cpp
             hle/kernel/thread.cpp
             hle/service/ac_u.cpp
@@ -106,6 +107,7 @@ set(HEADERS
             hle/kernel/event.h
             hle/kernel/kernel.h
             hle/kernel/mutex.h
+            hle/kernel/semaphore.h
             hle/kernel/shared_memory.h
             hle/kernel/thread.h
             hle/service/ac_u.h
diff --git a/src/core/hle/function_wrappers.h b/src/core/hle/function_wrappers.h
index 3dbe25037..dc3668624 100644
--- a/src/core/hle/function_wrappers.h
+++ b/src/core/hle/function_wrappers.h
@@ -114,6 +114,13 @@ template<s32 func(u32*, const char*)> void Wrap() {
     FuncReturn(retval);
 }
 
+template<s32 func(u32*, s32, s32)> void Wrap() {
+    u32 param_1 = 0;
+    u32 retval = func(&param_1, PARAM(1), PARAM(2));
+    Core::g_app_core->SetReg(1, param_1);
+    FuncReturn(retval);
+}
+
 ////////////////////////////////////////////////////////////////////////////////////////////////////
 // Function wrappers that return type u32
 
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
diff --git a/src/core/hle/svc.cpp b/src/core/hle/svc.cpp
index db0c42e74..107d12156 100644
--- a/src/core/hle/svc.cpp
+++ b/src/core/hle/svc.cpp
@@ -12,6 +12,7 @@
 #include "core/hle/kernel/address_arbiter.h"
 #include "core/hle/kernel/event.h"
 #include "core/hle/kernel/mutex.h"
+#include "core/hle/kernel/semaphore.h"
 #include "core/hle/kernel/shared_memory.h"
 #include "core/hle/kernel/thread.h"
 
@@ -288,6 +289,14 @@ static Result GetThreadId(u32* thread_id, Handle handle) {
     return result.raw;
 }
 
+/// Creates a semaphore
+static Result CreateSemaphore(Handle* semaphore, s32 initial_count, s32 max_count) {
+    *semaphore = Kernel::CreateSemaphore(initial_count, max_count);
+    DEBUG_LOG(SVC, "called initial_count=%d, max_count=%d, created handle=0x%08X",
+        initial_count, max_count, *semaphore);
+    return 0;
+}
+
 /// Query memory
 static Result QueryMemory(void* info, void* out, u32 addr) {
     LOG_ERROR(Kernel_SVC, "(UNIMPLEMENTED) called addr=0x%08X", addr);
@@ -366,7 +375,7 @@ const HLE::FunctionDef SVC_Table[] = {
     {0x12, nullptr,                         "Run"},
     {0x13, HLE::Wrap<CreateMutex>,          "CreateMutex"},
     {0x14, HLE::Wrap<ReleaseMutex>,         "ReleaseMutex"},
-    {0x15, nullptr,                         "CreateSemaphore"},
+    {0x15, HLE::Wrap<CreateSemaphore>,      "CreateSemaphore"},
     {0x16, nullptr,                         "ReleaseSemaphore"},
     {0x17, HLE::Wrap<CreateEvent>,          "CreateEvent"},
     {0x18, HLE::Wrap<SignalEvent>,          "SignalEvent"},