23 files changed, 689 insertions, 310 deletions

diff --git a/src/core/CMakeLists.txt b/src/core/CMakeLists.txt
index b3bfbca9e..48241c3d4 100644
--- a/src/core/CMakeLists.txt
+++ b/src/core/CMakeLists.txt
@@ -133,6 +133,7 @@ set(HEADERS
             hle/service/srv.h
             hle/service/ssl_c.h
             hle/config_mem.h
+            hle/result.h
             hle/function_wrappers.h
             hle/hle.h
             hle/svc.h
diff --git a/src/core/arm/skyeye_common/armdefs.h b/src/core/arm/skyeye_common/armdefs.h
index 6e8187c8e..8343aaa01 100644
--- a/src/core/arm/skyeye_common/armdefs.h
+++ b/src/core/arm/skyeye_common/armdefs.h
@@ -799,22 +799,24 @@ pascal void SpinCursor (short increment);    /* copied from CursorCtl.h */
 #include "list.h"
 #include "tb.h"
 */
-const int EQ = 0;
-const int NE = 1;
-const int CS = 2;
-const int CC = 3;
-const int MI = 4;
-const int PL = 5;
-const int VS = 6;
-const int VC = 7;
-const int HI = 8;
-const int LS = 9;
-const int GE = 10;
-const int LT = 11;
-const int GT = 12;
-const int LE = 13;
-const int AL = 14;
-const int NV = 15;
+enum ConditionCode {
+    EQ = 0,
+    NE = 1,
+    CS = 2,
+    CC = 3,
+    MI = 4,
+    PL = 5,
+    VS = 6,
+    VC = 7,
+    HI = 8,
+    LS = 9,
+    GE = 10,
+    LT = 11,
+    GT = 12,
+    LE = 13,
+    AL = 14,
+    NV = 15,
+};
 
 #ifndef NFLAG
 #define NFLAG    state->NFlag
diff --git a/src/core/hle/kernel/address_arbiter.cpp b/src/core/hle/kernel/address_arbiter.cpp
index 2b21657da..1e697fac1 100644
--- a/src/core/hle/kernel/address_arbiter.cpp
+++ b/src/core/hle/kernel/address_arbiter.cpp
@@ -30,17 +30,17 @@ public:
      * @param wait Boolean wait set if current thread should wait as a result of sync operation
      * @return Result of operation, 0 on success, otherwise error code
      */
-    Result WaitSynchronization(bool* wait) override {
+    ResultVal<bool> WaitSynchronization() override {
         // TODO(bunnei): ImplementMe
         ERROR_LOG(OSHLE, "(UNIMPLEMENTED)");
-        return 0;
+        return UnimplementedFunction(ErrorModule::OS);
     }
 };
 
 ////////////////////////////////////////////////////////////////////////////////////////////////////
 
 /// Arbitrate an address
-Result ArbitrateAddress(Handle handle, ArbitrationType type, u32 address, s32 value) {
+ResultCode ArbitrateAddress(Handle handle, ArbitrationType type, u32 address, s32 value) {
     switch (type) {
 
     // Signal thread(s) waiting for arbitrate address...
@@ -65,9 +65,9 @@ Result ArbitrateAddress(Handle handle, ArbitrationType type, u32 address, s32 va
 
     default:
         ERROR_LOG(KERNEL, "unknown type=%d", type);
-        return -1;
+        return ResultCode(ErrorDescription::InvalidEnumValue, ErrorModule::Kernel, ErrorSummary::WrongArgument, ErrorLevel::Usage);
     }
-    return 0;
+    return RESULT_SUCCESS;
 }
 
 /// Create an address arbiter
diff --git a/src/core/hle/kernel/address_arbiter.h b/src/core/hle/kernel/address_arbiter.h
index 6886e479d..8a5fb10b4 100644
--- a/src/core/hle/kernel/address_arbiter.h
+++ b/src/core/hle/kernel/address_arbiter.h
@@ -28,7 +28,7 @@ enum class ArbitrationType : u32 {
 };
 
 /// Arbitrate an address
-Result ArbitrateAddress(Handle handle, ArbitrationType type, u32 address, s32 value);
+ResultCode ArbitrateAddress(Handle handle, ArbitrationType type, u32 address, s32 value);
 
 /// Create an address arbiter
 Handle CreateAddressArbiter(const std::string& name = "Unknown");
diff --git a/src/core/hle/kernel/archive.cpp b/src/core/hle/kernel/archive.cpp
index 900f484c7..e11dddc84 100644
--- a/src/core/hle/kernel/archive.cpp
+++ b/src/core/hle/kernel/archive.cpp
@@ -9,8 +9,9 @@
 #include "core/file_sys/archive.h"
 #include "core/file_sys/archive_sdmc.h"
 #include "core/file_sys/directory.h"
-#include "core/hle/service/service.h"
 #include "core/hle/kernel/archive.h"
+#include "core/hle/result.h"
+#include "core/hle/service/service.h"
 
 ////////////////////////////////////////////////////////////////////////////////////////////////////
 // Kernel namespace
@@ -56,7 +57,7 @@ public:
      * @param wait Boolean wait set if current thread should wait as a result of sync operation
      * @return Result of operation, 0 on success, otherwise error code
      */
-    Result SyncRequest(bool* wait) override {
+    ResultVal<bool> SyncRequest() override {
         u32* cmd_buff = Service::GetCommandBuffer();
         FileCommand cmd = static_cast<FileCommand>(cmd_buff[0]);
 
@@ -106,11 +107,11 @@ public:
         default:
         {
             ERROR_LOG(KERNEL, "Unknown command=0x%08X!", cmd);
-            return -1;
+            return UnimplementedFunction(ErrorModule::FS);
         }
         }
         cmd_buff[1] = 0; // No error
-        return 0;
+        return MakeResult<bool>(false);
     }
 
     /**
@@ -118,10 +119,10 @@ public:
      * @param wait Boolean wait set if current thread should wait as a result of sync operation
      * @return Result of operation, 0 on success, otherwise error code
      */
-    Result WaitSynchronization(bool* wait) override {
+    ResultVal<bool> WaitSynchronization() override {
         // TODO(bunnei): ImplementMe
         ERROR_LOG(OSHLE, "(UNIMPLEMENTED)");
-        return 0;
+        return UnimplementedFunction(ErrorModule::FS);
     }
 };
 
@@ -141,7 +142,7 @@ public:
      * @param wait Boolean wait set if current thread should wait as a result of sync operation
      * @return Result of operation, 0 on success, otherwise error code
      */
-    Result SyncRequest(bool* wait) override {
+    ResultVal<bool> SyncRequest() override {
         u32* cmd_buff = Service::GetCommandBuffer();
         FileCommand cmd = static_cast<FileCommand>(cmd_buff[0]);
         switch (cmd) {
@@ -183,7 +184,8 @@ public:
         case FileCommand::SetSize:
         {
             u64 size = cmd_buff[1] | ((u64)cmd_buff[2] << 32);
-            DEBUG_LOG(KERNEL, "SetSize %s %s size=%llu", GetTypeName().c_str(), GetName().c_str(), size);
+            DEBUG_LOG(KERNEL, "SetSize %s %s size=%llu",
+                    GetTypeName().c_str(), GetName().c_str(), size);
             backend->SetSize(size);
             break;
         }
@@ -198,11 +200,12 @@ public:
         // Unknown command...
         default:
             ERROR_LOG(KERNEL, "Unknown command=0x%08X!", cmd);
-            cmd_buff[1] = -1; // TODO(Link Mauve): use the correct error code for that.
-            return -1;
+            ResultCode error = UnimplementedFunction(ErrorModule::FS);
+            cmd_buff[1] = error.raw; // TODO(Link Mauve): use the correct error code for that.
+            return error;
         }
         cmd_buff[1] = 0; // No error
-        return 0;
+        return MakeResult<bool>(false);
     }
 
     /**
@@ -210,10 +213,10 @@ public:
      * @param wait Boolean wait set if current thread should wait as a result of sync operation
      * @return Result of operation, 0 on success, otherwise error code
      */
-    Result WaitSynchronization(bool* wait) override {
+    ResultVal<bool> WaitSynchronization() override {
         // TODO(bunnei): ImplementMe
         ERROR_LOG(OSHLE, "(UNIMPLEMENTED)");
-        return 0;
+        return UnimplementedFunction(ErrorModule::FS);
     }
 };
 
@@ -233,7 +236,7 @@ public:
      * @param wait Boolean wait set if current thread should wait as a result of sync operation
      * @return Result of operation, 0 on success, otherwise error code
      */
-    Result SyncRequest(bool* wait) override {
+    ResultVal<bool> SyncRequest() override {
         u32* cmd_buff = Service::GetCommandBuffer();
         DirectoryCommand cmd = static_cast<DirectoryCommand>(cmd_buff[0]);
         switch (cmd) {
@@ -243,8 +246,9 @@ public:
         {
             u32 count = cmd_buff[1];
             u32 address = cmd_buff[3];
-            FileSys::Entry* entries = reinterpret_cast<FileSys::Entry*>(Memory::GetPointer(address));
-            DEBUG_LOG(KERNEL, "Read %s %s: count=%d", GetTypeName().c_str(), GetName().c_str(), count);
+            auto entries = reinterpret_cast<FileSys::Entry*>(Memory::GetPointer(address));
+            DEBUG_LOG(KERNEL, "Read %s %s: count=%d",
+                    GetTypeName().c_str(), GetName().c_str(), count);
 
             // Number of entries actually read
             cmd_buff[2] = backend->Read(count, entries);
@@ -261,11 +265,12 @@ public:
         // Unknown command...
         default:
             ERROR_LOG(KERNEL, "Unknown command=0x%08X!", cmd);
-            cmd_buff[1] = -1; // TODO(Link Mauve): use the correct error code for that.
-            return -1;
+            ResultCode error = UnimplementedFunction(ErrorModule::FS);
+            cmd_buff[1] = error.raw; // TODO(Link Mauve): use the correct error code for that.
+            return error;
         }
         cmd_buff[1] = 0; // No error
-        return 0;
+        return MakeResult<bool>(false);
     }
 
     /**
@@ -273,10 +278,10 @@ public:
      * @param wait Boolean wait set if current thread should wait as a result of sync operation
      * @return Result of operation, 0 on success, otherwise error code
      */
-    Result WaitSynchronization(bool* wait) override {
+    ResultVal<bool> WaitSynchronization() override {
         // TODO(bunnei): ImplementMe
         ERROR_LOG(OSHLE, "(UNIMPLEMENTED)");
-        return 0;
+        return UnimplementedFunction(ErrorModule::FS);
     }
 };
 
@@ -284,89 +289,59 @@ public:
 
 std::map<FileSys::Archive::IdCode, Handle> g_archive_map; ///< Map of file archives by IdCode
 
-/**
- * Opens an archive
- * @param id_code IdCode of the archive to open
- * @return Handle to archive if it exists, otherwise a null handle (0)
- */
-Handle OpenArchive(FileSys::Archive::IdCode id_code) {
+ResultVal<Handle> OpenArchive(FileSys::Archive::IdCode id_code) {
     auto itr = g_archive_map.find(id_code);
     if (itr == g_archive_map.end()) {
-        return 0;
+        return ResultCode(ErrorDescription::NotFound, ErrorModule::FS,
+                ErrorSummary::NotFound, ErrorLevel::Permanent);
     }
-    return itr->second;
+
+    return MakeResult<Handle>(itr->second);
 }
 
-/**
- * Closes an archive
- * @param id_code IdCode of the archive to open
- * @return Result of operation, 0 on success, otherwise error code
- */
-Result CloseArchive(FileSys::Archive::IdCode id_code) {
+ResultCode CloseArchive(FileSys::Archive::IdCode id_code) {
     auto itr = g_archive_map.find(id_code);
     if (itr == g_archive_map.end()) {
         ERROR_LOG(KERNEL, "Cannot close archive %d, does not exist!", (int)id_code);
-        return -1;
+        return InvalidHandle(ErrorModule::FS);
     }
 
     INFO_LOG(KERNEL, "Closed archive %d", (int) id_code);
-    return 0;
+    return RESULT_SUCCESS;
 }
 
 /**
  * Mounts an archive
  * @param archive Pointer to the archive to mount
- * @return Result of operation, 0 on success, otherwise error code
+ * @return Result of operation
  */
-Result MountArchive(Archive* archive) {
+ResultCode MountArchive(Archive* archive) {
     FileSys::Archive::IdCode id_code = archive->backend->GetIdCode();
-    if (0 != OpenArchive(id_code)) {
+    ResultVal<Handle> archive_handle = OpenArchive(id_code);
+    if (archive_handle.Succeeded()) {
         ERROR_LOG(KERNEL, "Cannot mount two archives with the same ID code! (%d)", (int) id_code);
-        return -1;
+        return archive_handle.Code();
     }
     g_archive_map[id_code] = archive->GetHandle();
     INFO_LOG(KERNEL, "Mounted archive %s", archive->GetName().c_str());
-    return 0;
+    return RESULT_SUCCESS;
 }
 
-/**
- * Creates an Archive
- * @param handle Handle to newly created archive object
- * @param backend File system backend interface to the archive
- * @param name Optional name of Archive
- * @return Newly created Archive object
- */
-Archive* CreateArchive(Handle& handle, FileSys::Archive* backend, const std::string& name) {
+ResultCode CreateArchive(FileSys::Archive* backend, const std::string& name) {
     Archive* archive = new Archive;
-    handle = Kernel::g_object_pool.Create(archive);
+    Handle handle = Kernel::g_object_pool.Create(archive);
     archive->name = name;
     archive->backend = backend;
 
-    MountArchive(archive);
-
-    return archive;
-}
-
-/**
- * Creates an Archive
- * @param backend File system backend interface to the archive
- * @param name Optional name of Archive
- * @return Handle to newly created Archive object
- */
-Handle CreateArchive(FileSys::Archive* backend, const std::string& name) {
-    Handle handle;
-    CreateArchive(handle, backend, name);
-    return handle;
+    ResultCode result = MountArchive(archive);
+    if (result.IsError()) {
+        return result;
+    }
+    
+    return RESULT_SUCCESS;
 }
 
-/**
- * Open a File from an Archive
- * @param archive_handle Handle to an open Archive object
- * @param path Path to the File inside of the Archive
- * @param mode Mode under which to open the File
- * @return Opened File object
- */
-Handle OpenFileFromArchive(Handle archive_handle, const FileSys::Path& path, const FileSys::Mode mode) {
+ResultVal<Handle> OpenFileFromArchive(Handle archive_handle, const FileSys::Path& path, const FileSys::Mode mode) {
     // TODO(bunnei): Binary type files get a raw file pointer to the archive. Currently, we create
     // the archive file handles at app loading, and then keep them persistent throughout execution.
     // Archives file handles are just reused and not actually freed until emulation shut down.
@@ -376,19 +351,24 @@ Handle OpenFileFromArchive(Handle archive_handle, const FileSys::Path& path, con
         // design. While the functionally of this is OK, our implementation decision to separate
         // normal files from archive file pointers is very likely wrong.
         // See https://github.com/citra-emu/citra/issues/205
-        return archive_handle;
+        return MakeResult<Handle>(archive_handle);
 
     File* file = new File;
     Handle handle = Kernel::g_object_pool.Create(file);
 
-    Archive* archive = Kernel::g_object_pool.GetFast<Archive>(archive_handle);
+    Archive* archive = Kernel::g_object_pool.Get<Archive>(archive_handle);
+    if (archive == nullptr) {
+        return InvalidHandle(ErrorModule::FS);
+    }
     file->path = path;
     file->backend = archive->backend->OpenFile(path, mode);
 
-    if (!file->backend)
-        return 0;
+    if (!file->backend) {
+        return ResultCode(ErrorDescription::NotFound, ErrorModule::FS,
+                ErrorSummary::NotFound, ErrorLevel::Permanent);
+    }
 
-    return handle;
+    return MakeResult<Handle>(handle);
 }
 
 /**
@@ -442,15 +422,18 @@ Result CreateDirectoryFromArchive(Handle archive_handle, const FileSys::Path& pa
  * @param path Path to the Directory inside of the Archive
  * @return Opened Directory object
  */
-Handle OpenDirectoryFromArchive(Handle archive_handle, const FileSys::Path& path) {
+ResultVal<Handle> OpenDirectoryFromArchive(Handle archive_handle, const FileSys::Path& path) {
     Directory* directory = new Directory;
     Handle handle = Kernel::g_object_pool.Create(directory);
 
-    Archive* archive = Kernel::g_object_pool.GetFast<Archive>(archive_handle);
+    Archive* archive = Kernel::g_object_pool.Get<Archive>(archive_handle);
+    if (archive == nullptr) {
+        return InvalidHandle(ErrorModule::FS);
+    }
     directory->path = path;
     directory->backend = archive->backend->OpenDirectory(path);
 
-    return handle;
+    return MakeResult<Handle>(handle);
 }
 
 /// Initialize archives
diff --git a/src/core/hle/kernel/archive.h b/src/core/hle/kernel/archive.h
index 95b3c6656..6fc4f0f25 100644
--- a/src/core/hle/kernel/archive.h
+++ b/src/core/hle/kernel/archive.h
@@ -6,8 +6,9 @@
 
 #include "common/common_types.h"
 
-#include "core/hle/kernel/kernel.h"
 #include "core/file_sys/archive.h"
+#include "core/hle/kernel/kernel.h"
+#include "core/hle/result.h"
 
 ////////////////////////////////////////////////////////////////////////////////////////////////////
 // Kernel namespace
@@ -17,33 +18,31 @@ namespace Kernel {
 /**
  * Opens an archive
  * @param id_code IdCode of the archive to open
- * @return Handle to archive if it exists, otherwise a null handle (0)
+ * @return Handle to the opened archive
  */
-Handle OpenArchive(FileSys::Archive::IdCode id_code);
+ResultVal<Handle> OpenArchive(FileSys::Archive::IdCode id_code);
 
 /**
  * Closes an archive
  * @param id_code IdCode of the archive to open
- * @return true if it worked fine
  */
-Result CloseArchive(FileSys::Archive::IdCode id_code);
+ResultCode CloseArchive(FileSys::Archive::IdCode id_code);
 
 /**
  * Creates an Archive
  * @param backend File system backend interface to the archive
- * @param name Optional name of Archive
- * @return Handle to newly created Archive object
+ * @param name Name of Archive
  */
-Handle CreateArchive(FileSys::Archive* backend, const std::string& name);
+ResultCode CreateArchive(FileSys::Archive* backend, const std::string& name);
 
 /**
  * Open a File from an Archive
  * @param archive_handle Handle to an open Archive object
  * @param path Path to the File inside of the Archive
  * @param mode Mode under which to open the File
- * @return Opened File object
+ * @return Handle to the opened File object
  */
-Handle OpenFileFromArchive(Handle archive_handle, const FileSys::Path& path, const FileSys::Mode mode);
+ResultVal<Handle> OpenFileFromArchive(Handle archive_handle, const FileSys::Path& path, const FileSys::Mode mode);
 
 /**
  * Delete a File from an Archive
@@ -73,9 +72,9 @@ Result CreateDirectoryFromArchive(Handle archive_handle, const FileSys::Path& pa
  * Open a Directory from an Archive
  * @param archive_handle Handle to an open Archive object
  * @param path Path to the Directory inside of the Archive
- * @return Opened Directory object
+ * @return Handle to the opened File object
  */
-Handle OpenDirectoryFromArchive(Handle archive_handle, const FileSys::Path& path);
+ResultVal<Handle> OpenDirectoryFromArchive(Handle archive_handle, const FileSys::Path& path);
 
 /// Initialize archives
 void ArchiveInit();
diff --git a/src/core/hle/kernel/event.cpp b/src/core/hle/kernel/event.cpp
index e0117c0bc..8a2925a3c 100644
--- a/src/core/hle/kernel/event.cpp
+++ b/src/core/hle/kernel/event.cpp
@@ -35,8 +35,8 @@ public:
      * @param wait Boolean wait set if current thread should wait as a result of sync operation
      * @return Result of operation, 0 on success, otherwise error code
      */
-    Result WaitSynchronization(bool* wait) override {
-        *wait = locked;
+    ResultVal<bool> WaitSynchronization() override {
+        bool wait = locked;
         if (locked) {
             Handle thread = GetCurrentThreadHandle();
             if (std::find(waiting_threads.begin(), waiting_threads.end(), thread) == waiting_threads.end()) {
@@ -47,7 +47,7 @@ public:
         if (reset_type != RESETTYPE_STICKY && !permanent_locked) {
             locked = true;
         }
-        return 0;
+        return MakeResult<bool>(wait);
     }
 };
 
@@ -57,12 +57,12 @@ public:
  * @param permanent_locked Boolean permanent locked value to set event
  * @return Result of operation, 0 on success, otherwise error code
  */
-Result SetPermanentLock(Handle handle, const bool permanent_locked) {
-    Event* evt = g_object_pool.GetFast<Event>(handle);
-    _assert_msg_(KERNEL, (evt != nullptr), "called, but event is nullptr!");
+ResultCode SetPermanentLock(Handle handle, const bool permanent_locked) {
+    Event* evt = g_object_pool.Get<Event>(handle);
+    if (evt == nullptr) return InvalidHandle(ErrorModule::Kernel);
 
     evt->permanent_locked = permanent_locked;
-    return 0;
+    return RESULT_SUCCESS;
 }
 
 /**
@@ -71,14 +71,14 @@ Result SetPermanentLock(Handle handle, const bool permanent_locked) {
  * @param locked Boolean locked value to set event
  * @return Result of operation, 0 on success, otherwise error code
  */
-Result SetEventLocked(const Handle handle, const bool locked) {
-    Event* evt = g_object_pool.GetFast<Event>(handle);
-    _assert_msg_(KERNEL, (evt != nullptr), "called, but event is nullptr!");
+ResultCode SetEventLocked(const Handle handle, const bool locked) {
+    Event* evt = g_object_pool.Get<Event>(handle);
+    if (evt == nullptr) return InvalidHandle(ErrorModule::Kernel);
 
     if (!evt->permanent_locked) {
         evt->locked = locked;
     }
-    return 0;
+    return RESULT_SUCCESS;
 }
 
 /**
@@ -86,9 +86,9 @@ Result SetEventLocked(const Handle handle, const bool locked) {
  * @param handle Handle to event to signal
  * @return Result of operation, 0 on success, otherwise error code
  */
-Result SignalEvent(const Handle handle) {
-    Event* evt = g_object_pool.GetFast<Event>(handle);
-    _assert_msg_(KERNEL, (evt != nullptr), "called, but event is nullptr!");
+ResultCode SignalEvent(const Handle handle) {
+    Event* evt = g_object_pool.Get<Event>(handle);
+    if (evt == nullptr) return InvalidHandle(ErrorModule::Kernel);
 
     // Resume threads waiting for event to signal
     bool event_caught = false;
@@ -106,7 +106,7 @@ Result SignalEvent(const Handle handle) {
     if (!evt->permanent_locked) {
         evt->locked = event_caught;
     }
-    return 0;
+    return RESULT_SUCCESS;
 }
 
 /**
@@ -114,14 +114,14 @@ Result SignalEvent(const Handle handle) {
  * @param handle Handle to event to clear
  * @return Result of operation, 0 on success, otherwise error code
  */
-Result ClearEvent(Handle handle) {
-    Event* evt = g_object_pool.GetFast<Event>(handle);
-    _assert_msg_(KERNEL, (evt != nullptr), "called, but event is nullptr!");
+ResultCode ClearEvent(Handle handle) {
+    Event* evt = g_object_pool.Get<Event>(handle);
+    if (evt == nullptr) return InvalidHandle(ErrorModule::Kernel);
 
     if (!evt->permanent_locked) {
         evt->locked = true;
     }
-    return 0;
+    return RESULT_SUCCESS;
 }
 
 /**
diff --git a/src/core/hle/kernel/event.h b/src/core/hle/kernel/event.h
index 6add72897..6c17ed232 100644
--- a/src/core/hle/kernel/event.h
+++ b/src/core/hle/kernel/event.h
@@ -17,7 +17,7 @@ namespace Kernel {
  * @param locked Boolean locked value to set event
  * @return Result of operation, 0 on success, otherwise error code
  */
-Result SetEventLocked(const Handle handle, const bool locked);
+ResultCode SetEventLocked(const Handle handle, const bool locked);
 
 /**
  * Hackish function to set an events permanent lock state, used to pass through synch blocks
@@ -25,21 +25,21 @@ Result SetEventLocked(const Handle handle, const bool locked);
  * @param permanent_locked Boolean permanent locked value to set event
  * @return Result of operation, 0 on success, otherwise error code
  */
-Result SetPermanentLock(Handle handle, const bool permanent_locked);
+ResultCode SetPermanentLock(Handle handle, const bool permanent_locked);
 
 /**
  * Signals an event
  * @param handle Handle to event to signal
  * @return Result of operation, 0 on success, otherwise error code
  */
-Result SignalEvent(const Handle handle);
+ResultCode SignalEvent(const Handle handle);
 
 /**
  * Clears an event
  * @param handle Handle to event to clear
  * @return Result of operation, 0 on success, otherwise error code
  */
-Result ClearEvent(Handle handle);
+ResultCode ClearEvent(Handle handle);
 
 /**
  * Creates an event
diff --git a/src/core/hle/kernel/kernel.h b/src/core/hle/kernel/kernel.h
index e0c94f186..8d3937ce8 100644
--- a/src/core/hle/kernel/kernel.h
+++ b/src/core/hle/kernel/kernel.h
@@ -7,6 +7,7 @@
 #include <array>
 #include <string>
 #include "common/common.h"
+#include "core/hle/result.h"
 
 typedef u32 Handle;
 typedef s32 Result;
@@ -52,21 +53,19 @@ public:
     virtual Kernel::HandleType GetHandleType() const = 0;
 
     /**
-     * Synchronize kernel object
-     * @param wait Boolean wait set if current thread should wait as a result of sync operation
-     * @return Result of operation, 0 on success, otherwise error code
+     * Synchronize kernel object.
+     * @return True if the current thread should wait as a result of the sync
      */
-    virtual Result SyncRequest(bool* wait) {
+    virtual ResultVal<bool> SyncRequest() {
         ERROR_LOG(KERNEL, "(UNIMPLEMENTED)");
-        return -1;
+        return UnimplementedFunction(ErrorModule::Kernel);
     }
 
     /**
-     * Wait for kernel object to synchronize
-     * @param wait Boolean wait set if current thread should wait as a result of sync operation
-     * @return Result of operation, 0 on success, otherwise error code
+     * Wait for kernel object to synchronize.
+     * @return True if the current thread should wait as a result of the wait
      */
-    virtual Result WaitSynchronization(bool* wait) = 0;
+    virtual ResultVal<bool> WaitSynchronization() = 0;
 };
 
 class ObjectPool : NonCopyable {
@@ -80,38 +79,29 @@ public:
     static Object* CreateByIDType(int type);
 
     template <class T>
-    u32 Destroy(Handle handle) {
-        u32 error;
-        if (Get<T>(handle, error)) {
+    void Destroy(Handle handle) {
+        if (Get<T>(handle)) {
             occupied[handle - HANDLE_OFFSET] = false;
             delete pool[handle - HANDLE_OFFSET];
         }
-        return error;
     }
 
     bool IsValid(Handle handle);
 
     template <class T>
-    T* Get(Handle handle, u32& outError) {
+    T* Get(Handle handle) {
         if (handle < HANDLE_OFFSET || handle >= HANDLE_OFFSET + MAX_COUNT || !occupied[handle - HANDLE_OFFSET]) {
-            // Tekken 6 spams 0x80020001 gets wrong with no ill effects, also on the real PSP
-            if (handle != 0 && (u32)handle != 0x80020001) {
+            if (handle != 0) {
                 WARN_LOG(KERNEL, "Kernel: Bad object handle %i (%08x)", handle, handle);
             }
-            outError = 0;//T::GetMissingErrorCode();
-            return 0;
+            return nullptr;
         } else {
-            // Previously we had a dynamic_cast here, but since RTTI was disabled traditionally,
-            // it just acted as a static case and everything worked. This means that we will never
-            // see the Wrong type object error below, but we'll just have to live with that danger.
-            T* t = static_cast<T*>(pool[handle - HANDLE_OFFSET]);
-            if (t == 0 || t->GetHandleType() != T::GetStaticHandleType()) {
+            Object* t = pool[handle - HANDLE_OFFSET];
+            if (t->GetHandleType() != T::GetStaticHandleType()) {
                 WARN_LOG(KERNEL, "Kernel: Wrong object type for %i (%08x)", handle, handle);
-                outError = 0;//T::GetMissingErrorCode();
-                return 0;
+                return nullptr;
             }
-            outError = 0;//SCE_KERNEL_ERROR_OK;
-            return t;
+            return static_cast<T*>(t);
         }
     }
 
diff --git a/src/core/hle/kernel/mutex.cpp b/src/core/hle/kernel/mutex.cpp
index 31129fd86..e4ff1ef40 100644
--- a/src/core/hle/kernel/mutex.cpp
+++ b/src/core/hle/kernel/mutex.cpp
@@ -32,10 +32,10 @@ public:
      * @param wait Boolean wait set if current thread should wait as a result of sync operation
      * @return Result of operation, 0 on success, otherwise error code
      */
-    Result SyncRequest(bool* wait) override {
+    ResultVal<bool> SyncRequest() override {
         // TODO(bunnei): ImplementMe
         locked = true;
-        return 0;
+        return MakeResult<bool>(false);
     }
 
     /**
@@ -43,15 +43,14 @@ public:
      * @param wait Boolean wait set if current thread should wait as a result of sync operation
      * @return Result of operation, 0 on success, otherwise error code
      */
-    Result WaitSynchronization(bool* wait) override {
+    ResultVal<bool> WaitSynchronization() override {
         // TODO(bunnei): ImplementMe
-        *wait = locked;
-
+        bool wait = locked;
         if (locked) {
             Kernel::WaitCurrentThread(WAITTYPE_MUTEX, GetHandle());
         }
 
-        return 0;
+        return MakeResult<bool>(wait);
     }
 };
 
@@ -119,15 +118,17 @@ bool ReleaseMutex(Mutex* mutex) {
  * Releases a mutex
  * @param handle Handle to mutex to release
  */
-Result ReleaseMutex(Handle handle) {
-    Mutex* mutex = Kernel::g_object_pool.GetFast<Mutex>(handle);
-
-    _assert_msg_(KERNEL, (mutex != nullptr), "ReleaseMutex tried to release a nullptr mutex!");
+ResultCode ReleaseMutex(Handle handle) {
+    Mutex* mutex = Kernel::g_object_pool.Get<Mutex>(handle);
+    if (mutex == nullptr) return InvalidHandle(ErrorModule::Kernel);
 
     if (!ReleaseMutex(mutex)) {
-        return -1;
+        // TODO(yuriks): Verify error code, this one was pulled out of thin air. I'm not even sure
+        // what error condition this is supposed to be signaling.
+        return ResultCode(ErrorDescription::AlreadyDone, ErrorModule::Kernel,
+                ErrorSummary::NothingHappened, ErrorLevel::Temporary);
     }
-    return 0;
+    return RESULT_SUCCESS;
 }
 
 /**
diff --git a/src/core/hle/kernel/mutex.h b/src/core/hle/kernel/mutex.h
index 313ba6fee..233d8c420 100644
--- a/src/core/hle/kernel/mutex.h
+++ b/src/core/hle/kernel/mutex.h
@@ -15,7 +15,7 @@ namespace Kernel {
  * @param handle Handle to mutex to release
  * @return Result of operation, 0 on success, otherwise error code
  */
-Result ReleaseMutex(Handle handle);
+ResultCode ReleaseMutex(Handle handle);
 
 /**
  * Creates a mutex
diff --git a/src/core/hle/kernel/shared_memory.cpp b/src/core/hle/kernel/shared_memory.cpp
index 7ef3e54cc..b91fc98da 100644
--- a/src/core/hle/kernel/shared_memory.cpp
+++ b/src/core/hle/kernel/shared_memory.cpp
@@ -21,10 +21,10 @@ public:
      * @param wait Boolean wait set if current thread should wait as a result of sync operation
      * @return Result of operation, 0 on success, otherwise error code
      */
-    Result WaitSynchronization(bool* wait) override {
+    ResultVal<bool> WaitSynchronization() override {
         // TODO(bunnei): ImplementMe
         ERROR_LOG(OSHLE, "(UNIMPLEMENTED)");
-        return 0;
+        return UnimplementedFunction(ErrorModule::OS);
     }
 
     u32 base_address;                   ///< Address of shared memory block in RAM
@@ -67,22 +67,23 @@ Handle CreateSharedMemory(const std::string& name) {
  * @param other_permissions Memory block map other permissions (specified by SVC field)
  * @return Result of operation, 0 on success, otherwise error code
  */
-Result MapSharedMemory(u32 handle, u32 address, MemoryPermission permissions,
+ResultCode MapSharedMemory(u32 handle, u32 address, MemoryPermission permissions,
     MemoryPermission other_permissions) {
 
     if (address < Memory::SHARED_MEMORY_VADDR || address >= Memory::SHARED_MEMORY_VADDR_END) {
         ERROR_LOG(KERNEL, "cannot map handle=0x%08X, address=0x%08X outside of shared mem bounds!",
             handle, address);
-        return -1;
+        return ResultCode(ErrorDescription::InvalidAddress, ErrorModule::Kernel,
+                ErrorSummary::InvalidArgument, ErrorLevel::Permanent);
     }
-    SharedMemory* shared_memory = Kernel::g_object_pool.GetFast<SharedMemory>(handle);
-    _assert_msg_(KERNEL, (shared_memory != nullptr), "handle 0x%08X is not valid!", handle);
+    SharedMemory* shared_memory = Kernel::g_object_pool.Get<SharedMemory>(handle);
+    if (shared_memory == nullptr) return InvalidHandle(ErrorModule::Kernel);
 
     shared_memory->base_address = address;
     shared_memory->permissions = permissions;
     shared_memory->other_permissions = other_permissions;
 
-    return 0;
+    return RESULT_SUCCESS;
 }
 
 /**
@@ -91,15 +92,17 @@ Result MapSharedMemory(u32 handle, u32 address, MemoryPermission permissions,
  * @param offset Offset from the start of the shared memory block to get pointer
  * @return Pointer to the shared memory block from the specified offset
  */
-u8* GetSharedMemoryPointer(Handle handle, u32 offset) {
-    SharedMemory* shared_memory = Kernel::g_object_pool.GetFast<SharedMemory>(handle);
-    _assert_msg_(KERNEL, (shared_memory != nullptr), "handle 0x%08X is not valid!", handle);
+ResultVal<u8*> GetSharedMemoryPointer(Handle handle, u32 offset) {
+    SharedMemory* shared_memory = Kernel::g_object_pool.Get<SharedMemory>(handle);
+    if (shared_memory == nullptr) return InvalidHandle(ErrorModule::Kernel);
 
     if (0 != shared_memory->base_address)
-        return Memory::GetPointer(shared_memory->base_address + offset);
+        return MakeResult<u8*>(Memory::GetPointer(shared_memory->base_address + offset));
 
     ERROR_LOG(KERNEL, "memory block handle=0x%08X not mapped!", handle);
-    return nullptr;
+    // TODO(yuriks): Verify error code.
+    return ResultCode(ErrorDescription::InvalidAddress, ErrorModule::Kernel,
+            ErrorSummary::InvalidState, ErrorLevel::Permanent);
 }
 
 } // namespace
diff --git a/src/core/hle/kernel/shared_memory.h b/src/core/hle/kernel/shared_memory.h
index 0aec03538..6ed427088 100644
--- a/src/core/hle/kernel/shared_memory.h
+++ b/src/core/hle/kernel/shared_memory.h
@@ -34,7 +34,7 @@ Handle CreateSharedMemory(const std::string& name="Unknown");
  * @param other_permissions Memory block map other permissions (specified by SVC field)
  * @return Result of operation, 0 on success, otherwise error code
  */
-Result MapSharedMemory(u32 handle, u32 address, MemoryPermission permissions,
+ResultCode MapSharedMemory(Handle handle, u32 address, MemoryPermission permissions,
     MemoryPermission other_permissions);
 
 /**
@@ -43,6 +43,6 @@ Result MapSharedMemory(u32 handle, u32 address, MemoryPermission permissions,
  * @param offset Offset from the start of the shared memory block to get pointer
  * @return Pointer to the shared memory block from the specified offset
  */
-u8* GetSharedMemoryPointer(Handle handle, u32 offset);
+ResultVal<u8*> GetSharedMemoryPointer(Handle handle, u32 offset);
 
 } // namespace
diff --git a/src/core/hle/kernel/thread.cpp b/src/core/hle/kernel/thread.cpp
index cc70cbca7..b01779f2e 100644
--- a/src/core/hle/kernel/thread.cpp
+++ b/src/core/hle/kernel/thread.cpp
@@ -11,10 +11,11 @@
 #include "common/thread_queue_list.h"
 
 #include "core/core.h"
-#include "core/mem_map.h"
 #include "core/hle/hle.h"
 #include "core/hle/kernel/kernel.h"
 #include "core/hle/kernel/thread.h"
+#include "core/hle/result.h"
+#include "core/mem_map.h"
 
 namespace Kernel {
 
@@ -38,16 +39,17 @@ public:
      * @param wait Boolean wait set if current thread should wait as a result of sync operation
      * @return Result of operation, 0 on success, otherwise error code
      */
-    Result WaitSynchronization(bool* wait) override {
+    ResultVal<bool> WaitSynchronization() override {
         if (status != THREADSTATUS_DORMANT) {
             Handle thread = GetCurrentThreadHandle();
             if (std::find(waiting_threads.begin(), waiting_threads.end(), thread) == waiting_threads.end()) {
                 waiting_threads.push_back(thread);
             }
             WaitCurrentThread(WAITTYPE_THREADEND, this->GetHandle());
-            *wait = true;
+            return MakeResult<bool>(true);
+        } else {
+            return MakeResult<bool>(false);
         }
-        return 0;
     }
 
     ThreadContext context;
@@ -144,9 +146,9 @@ void ChangeReadyState(Thread* t, bool ready) {
 }
 
 /// Verify that a thread has not been released from waiting
-inline bool VerifyWait(const Handle& handle, WaitType type, Handle wait_handle) {
-    Thread* thread = g_object_pool.GetFast<Thread>(handle);
-    _assert_msg_(KERNEL, (thread != nullptr), "called, but thread is nullptr!");
+inline bool VerifyWait(Handle handle, WaitType type, Handle wait_handle) {
+    Thread* thread = g_object_pool.Get<Thread>(handle);
+    _dbg_assert_(KERNEL, thread != nullptr);
 
     if (type != thread->wait_type || wait_handle != thread->wait_handle)
         return false;
@@ -155,9 +157,9 @@ inline bool VerifyWait(const Handle& handle, WaitType type, Handle wait_handle)
 }
 
 /// Stops the current thread
-void StopThread(Handle handle, const char* reason) {
-    Thread* thread = g_object_pool.GetFast<Thread>(handle);
-    _assert_msg_(KERNEL, (thread != nullptr), "called, but thread is nullptr!");
+ResultCode StopThread(Handle handle, const char* reason) {
+    Thread* thread = g_object_pool.Get<Thread>(handle);
+    if (thread == nullptr) return InvalidHandle(ErrorModule::Kernel);
 
     ChangeReadyState(thread, false);
     thread->status = THREADSTATUS_DORMANT;
@@ -172,6 +174,8 @@ void StopThread(Handle handle, const char* reason) {
     // Stopped threads are never waiting.
     thread->wait_type = WAITTYPE_NONE;
     thread->wait_handle = 0;
+
+    return RESULT_SUCCESS;
 }
 
 /// Changes a threads state
@@ -201,7 +205,9 @@ Handle ArbitrateHighestPriorityThread(u32 arbiter, u32 address) {
         if (!VerifyWait(handle, WAITTYPE_ARB, arbiter))
             continue;
 
-        Thread* thread = g_object_pool.GetFast<Thread>(handle);
+        Thread* thread = g_object_pool.Get<Thread>(handle);
+        if (thread == nullptr)
+            continue; // TODO(yuriks): Thread handle will hang around forever. Should clean up.
         if(thread->current_priority <= priority) {
             highest_priority_thread = handle;
             priority = thread->current_priority;
@@ -272,7 +278,7 @@ Thread* NextThread() {
     if (next == 0) {
         return nullptr;
     }
-    return Kernel::g_object_pool.GetFast<Thread>(next);
+    return Kernel::g_object_pool.Get<Thread>(next);
 }
 
 /**
@@ -289,8 +295,7 @@ void WaitCurrentThread(WaitType wait_type, Handle wait_handle) {
 
 /// Resumes a thread from waiting by marking it as "ready"
 void ResumeThreadFromWait(Handle handle) {
-    u32 error;
-    Thread* thread = Kernel::g_object_pool.Get<Thread>(handle, error);
+    Thread* thread = Kernel::g_object_pool.Get<Thread>(handle);
     if (thread) {
         thread->status &= ~THREADSTATUS_WAIT;
         if (!(thread->status & (THREADSTATUS_WAITSUSPEND | THREADSTATUS_DORMANT | THREADSTATUS_DEAD))) {
@@ -378,19 +383,23 @@ Handle CreateThread(const char* name, u32 entry_point, s32 priority, u32 arg, s3
 }
 
 /// Get the priority of the thread specified by handle
-u32 GetThreadPriority(const Handle handle) {
-    Thread* thread = g_object_pool.GetFast<Thread>(handle);
-    _assert_msg_(KERNEL, (thread != nullptr), "called, but thread is nullptr!");
-    return thread->current_priority;
+ResultVal<u32> GetThreadPriority(const Handle handle) {
+    Thread* thread = g_object_pool.Get<Thread>(handle);
+    if (thread == nullptr) return InvalidHandle(ErrorModule::Kernel);
+
+    return MakeResult<u32>(thread->current_priority);
 }
 
 /// Set the priority of the thread specified by handle
-Result SetThreadPriority(Handle handle, s32 priority) {
+ResultCode SetThreadPriority(Handle handle, s32 priority) {
     Thread* thread = nullptr;
     if (!handle) {
         thread = GetCurrentThread(); // TODO(bunnei): Is this correct behavior?
     } else {
-        thread = g_object_pool.GetFast<Thread>(handle);
+        thread = g_object_pool.Get<Thread>(handle);
+        if (thread == nullptr) {
+            return InvalidHandle(ErrorModule::Kernel);
+        }
     }
     _assert_msg_(KERNEL, (thread != nullptr), "called, but thread is nullptr!");
 
@@ -417,7 +426,7 @@ Result SetThreadPriority(Handle handle, s32 priority) {
         thread_ready_queue.push_back(thread->current_priority, handle);
     }
 
-    return 0;
+    return RESULT_SUCCESS;
 }
 
 /// Sets up the primary application thread
diff --git a/src/core/hle/kernel/thread.h b/src/core/hle/kernel/thread.h
index 2a43797ee..ce63a70d3 100644
--- a/src/core/hle/kernel/thread.h
+++ b/src/core/hle/kernel/thread.h
@@ -6,6 +6,7 @@
 
 #include "common/common_types.h"
 #include "core/hle/kernel/kernel.h"
+#include "core/hle/result.h"
 
 enum ThreadPriority {
     THREADPRIO_HIGHEST      = 0,    ///< Highest thread priority
@@ -55,7 +56,7 @@ Handle SetupMainThread(s32 priority, int stack_size=Kernel::DEFAULT_STACK_SIZE);
 void Reschedule();
 
 /// Stops the current thread
-void StopThread(Handle thread, const char* reason);
+ResultCode StopThread(Handle thread, const char* reason);
 
 /// Resumes a thread from waiting by marking it as "ready"
 void ResumeThreadFromWait(Handle handle);
@@ -80,10 +81,10 @@ void WaitCurrentThread(WaitType wait_type, Handle wait_handle=GetCurrentThreadHa
 void WaitThread_Synchronization();
 
 /// Get the priority of the thread specified by handle
-u32 GetThreadPriority(const Handle handle);
+ResultVal<u32> GetThreadPriority(const Handle handle);
 
 /// Set the priority of the thread specified by handle
-Result SetThreadPriority(Handle handle, s32 priority);
+ResultCode SetThreadPriority(Handle handle, s32 priority);
 
 /// Initialize threading
 void ThreadingInit();
diff --git a/src/core/hle/result.h b/src/core/hle/result.h
new file mode 100644
index 000000000..15c4a2677
--- /dev/null
+++ b/src/core/hle/result.h
@@ -0,0 +1,400 @@
+// Copyright 2014 Citra Emulator Project
+// Licensed under GPLv2
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <cassert>
+#include <cstddef>
+#include <type_traits>
+#include <utility>
+
+#include "common/common_types.h"
+#include "common/bit_field.h"
+
+// All the constants in this file come from http://3dbrew.org/wiki/Error_codes
+
+/// Detailed description of the error. This listing is likely incomplete.
+enum class ErrorDescription : u32 {
+    Success = 0,
+    InvalidSection = 1000,
+    TooLarge = 1001,
+    NotAuthorized = 1002,
+    AlreadyDone = 1003,
+    InvalidSize = 1004,
+    InvalidEnumValue = 1005,
+    InvalidCombination = 1006,
+    NoData = 1007,
+    Busy = 1008,
+    MisalignedAddress = 1009,
+    MisalignedSize = 1010,
+    OutOfMemory = 1011,
+    NotImplemented = 1012,
+    InvalidAddress = 1013,
+    InvalidPointer = 1014,
+    InvalidHandle = 1015,
+    NotInitialized = 1016,
+    AlreadyInitialized = 1017,
+    NotFound = 1018,
+    CancelRequested = 1019,
+    AlreadyExists = 1020,
+    OutOfRange = 1021,
+    Timeout = 1022,
+    InvalidResultValue = 1023,
+};
+
+/**
+ * Identifies the module which caused the error. Error codes can be propagated through a call
+ * chain, meaning that this doesn't always correspond to the module where the API call made is
+ * contained.
+ */
+enum class ErrorModule : u32 {
+    Common = 0,
+    Kernel = 1,
+    Util = 2,
+    FileServer = 3,
+    LoaderServer = 4,
+    TCB = 5,
+    OS = 6,
+    DBG = 7,
+    DMNT = 8,
+    PDN = 9,
+    GX = 10,
+    I2C = 11,
+    GPIO = 12,
+    DD = 13,
+    CODEC = 14,
+    SPI = 15,
+    PXI = 16,
+    FS = 17,
+    DI = 18,
+    HID = 19,
+    CAM = 20,
+    PI = 21,
+    PM = 22,
+    PM_LOW = 23,
+    FSI = 24,
+    SRV = 25,
+    NDM = 26,
+    NWM = 27,
+    SOC = 28,
+    LDR = 29,
+    ACC = 30,
+    RomFS = 31,
+    AM = 32,
+    HIO = 33,
+    Updater = 34,
+    MIC = 35,
+    FND = 36,
+    MP = 37,
+    MPWL = 38,
+    AC = 39,
+    HTTP = 40,
+    DSP = 41,
+    SND = 42,
+    DLP = 43,
+    HIO_LOW = 44,
+    CSND = 45,
+    SSL = 46,
+    AM_LOW = 47,
+    NEX = 48,
+    Friends = 49,
+    RDT = 50,
+    Applet = 51,
+    NIM = 52,
+    PTM = 53,
+    MIDI = 54,
+    MC = 55,
+    SWC = 56,
+    FatFS = 57,
+    NGC = 58,
+    CARD = 59,
+    CARDNOR = 60,
+    SDMC = 61,
+    BOSS = 62,
+    DBM = 63,
+    Config = 64,
+    PS = 65,
+    CEC = 66,
+    IR = 67,
+    UDS = 68,
+    PL = 69,
+    CUP = 70,
+    Gyroscope = 71,
+    MCU = 72,
+    NS = 73,
+    News = 74,
+    RO_1 = 75,
+    GD = 76,
+    CardSPI = 77,
+    EC = 78,
+    RO_2 = 79,
+    WebBrowser = 80,
+    Test = 81,
+    ENC = 82,
+    PIA = 83,
+
+    Application = 254,
+    InvalidResult = 255
+};
+
+/// A less specific error cause.
+enum class ErrorSummary : u32 {
+    Success = 0,
+    NothingHappened = 1,
+    WouldBlock = 2,
+    OutOfResource = 3,      ///< There are no more kernel resources (memory, table slots) to
+                            ///< execute the operation.
+    NotFound = 4,           ///< A file or resource was not found.
+    InvalidState = 5,
+    NotSupported = 6,       ///< The operation is not supported or not implemented.
+    InvalidArgument = 7,    ///< Returned when a passed argument is invalid in the current runtime
+                            ///< context. (Invalid handle, out-of-bounds pointer or size, etc.)
+    WrongArgument = 8,      ///< Returned when a passed argument is in an incorrect format for use
+                            ///< with the function. (E.g. Invalid enum value)
+    Canceled = 9,
+    StatusChanged = 10,
+    Internal = 11,
+
+    InvalidResult = 63
+};
+
+/// The severity of the error.
+enum class ErrorLevel : u32 {
+    Success = 0,
+    Info = 1,
+
+    Status = 25,
+    Temporary = 26,
+    Permanent = 27,
+    Usage = 28,
+    Reinitialize = 29,
+    Reset = 30,
+    Fatal = 31
+};
+
+/// Encapsulates a CTR-OS error code, allowing it to be separated into its constituent fields.
+union ResultCode {
+    u32 raw;
+
+    BitField<0, 10, ErrorDescription> description;
+    BitField<10, 8, ErrorModule> module;
+
+    BitField<21, 6, ErrorSummary> summary;
+    BitField<27, 5, ErrorLevel> level;
+
+    // The last bit of `level` is checked by apps and the kernel to determine if a result code is an error
+    BitField<31, 1, u32> is_error;
+
+    explicit ResultCode(u32 raw) : raw(raw) {}
+    ResultCode(ErrorDescription description_, ErrorModule module_,
+            ErrorSummary summary_, ErrorLevel level_) : raw(0) {
+        description = description_;
+        module = module_;
+        summary = summary_;
+        level = level_;
+    }
+
+    ResultCode& operator=(const ResultCode& o) { raw = o.raw; return *this; }
+
+    bool IsSuccess() const {
+        return is_error == 0;
+    }
+
+    bool IsError() const {
+        return is_error == 1;
+    }
+};
+
+inline bool operator==(const ResultCode a, const ResultCode b) {
+    return a.raw == b.raw;
+}
+
+inline bool operator!=(const ResultCode a, const ResultCode b) {
+    return a.raw != b.raw;
+}
+
+// Convenience functions for creating some common kinds of errors:
+
+/// The default success `ResultCode`.
+const ResultCode RESULT_SUCCESS(0);
+
+/// Might be returned instead of a dummy success for unimplemented APIs.
+inline ResultCode UnimplementedFunction(ErrorModule module) {
+    return ResultCode(ErrorDescription::NotImplemented, module,
+            ErrorSummary::NotSupported, ErrorLevel::Permanent);
+}
+/// Returned when a function is passed an invalid handle.
+inline ResultCode InvalidHandle(ErrorModule module) {
+    return ResultCode(ErrorDescription::InvalidHandle, module,
+            ErrorSummary::InvalidArgument, ErrorLevel::Permanent);
+}
+
+/**
+ * This is an optional value type. It holds a `ResultCode` and, if that code is a success code,
+ * also holds a result of type `T`. If the code is an error code then trying to access the inner
+ * value fails, thus ensuring that the ResultCode of functions is always checked properly before
+ * their return value is used.  It is similar in concept to the `std::optional` type
+ * (http://en.cppreference.com/w/cpp/experimental/optional) originally proposed for inclusion in
+ * C++14, or the `Result` type in Rust (http://doc.rust-lang.org/std/result/index.html).
+ *
+ * An example of how it could be used:
+ * \code
+ * ResultVal<int> Frobnicate(float strength) {
+ *     if (strength < 0.f || strength > 1.0f) {
+ *         // Can't frobnicate too weakly or too strongly
+ *         return ResultCode(ErrorDescription::OutOfRange, ErrorModule::Common,
+ *             ErrorSummary::InvalidArgument, ErrorLevel::Permanent);
+ *     } else {
+ *         // Frobnicated! Give caller a cookie
+ *         return MakeResult<int>(42);
+ *     }
+ * }
+ * \endcode
+ *
+ * \code
+ * ResultVal<int> frob_result = Frobnicate(0.75f);
+ * if (frob_result) {
+ *     // Frobbed ok
+ *     printf("My cookie is %d\n", *frob_result);
+ * } else {
+ *     printf("Guess I overdid it. :( Error code: %ux\n", frob_result.code().hex);
+ * }
+ * \endcode
+ */
+template <typename T>
+class ResultVal {
+public:
+    /// Constructs an empty `ResultVal` with the given error code. The code must not be a success code.
+    ResultVal(ResultCode error_code = ResultCode(-1))
+        : result_code(error_code)
+    {
+        assert(error_code.IsError());
+        UpdateDebugPtr();
+    }
+
+    /**
+     * Similar to the non-member function `MakeResult`, with the exception that you can manually
+     * specify the success code. `success_code` must not be an error code.
+     */
+    template <typename... Args>
+    static ResultVal WithCode(ResultCode success_code, Args&&... args) {
+        ResultVal<T> result;
+        result.emplace(success_code, std::forward<Args>(args)...);
+        return result;
+    }
+
+    ResultVal(const ResultVal& o)
+        : result_code(o.result_code)
+    {
+        if (!o.empty()) {
+            new (&storage) T(*o.GetPointer());
+        }
+        UpdateDebugPtr();
+    }
+
+    ResultVal(ResultVal&& o)
+        : result_code(o.result_code)
+    {
+        if (!o.empty()) {
+            new (&storage) T(std::move(*o.GetPointer()));
+        }
+        UpdateDebugPtr();
+    }
+
+    ~ResultVal() {
+        if (!empty()) {
+            GetPointer()->~T();
+        }
+    }
+
+    ResultVal& operator=(const ResultVal& o) {
+        if (*this) {
+            if (o) {
+                *GetPointer() = *o.GetPointer();
+            } else {
+                GetPointer()->~T();
+            }
+        } else {
+            if (o) {
+                new (&storage) T(*o.GetPointer());
+            }
+        }
+        result_code = o.result_code;
+        UpdateDebugPtr();
+
+        return *this;
+    }
+
+    /**
+     * Replaces the current result with a new constructed result value in-place. The code must not
+     * be an error code.
+     */
+    template <typename... Args>
+    void emplace(ResultCode success_code, Args&&... args) {
+        assert(success_code.IsSuccess());
+        if (!empty()) {
+            GetPointer()->~T();
+        }
+        new (&storage) T(std::forward<Args>(args)...);
+        result_code = success_code;
+        UpdateDebugPtr();
+    }
+
+    /// Returns true if the `ResultVal` contains an error code and no value.
+    bool empty() const { return result_code.IsError(); }
+
+    /// Returns true if the `ResultVal` contains a return value.
+    bool Succeeded() const { return result_code.IsSuccess(); }
+    /// Returns true if the `ResultVal` contains an error code and no value.
+    bool Failed() const { return empty(); }
+
+    ResultCode Code() const { return result_code; }
+
+    const T& operator* () const { return *GetPointer(); }
+          T& operator* ()       { return *GetPointer(); }
+    const T* operator->() const { return  GetPointer(); }
+          T* operator->()       { return  GetPointer(); }
+
+    /// Returns the value contained in this `ResultVal`, or the supplied default if it is missing.
+    template <typename U>
+    T ValueOr(U&& value) const {
+        return !empty() ? *GetPointer() : std::move(value);
+    }
+
+private:
+    typedef typename std::aligned_storage<sizeof(T), std::alignment_of<T>::value>::type StorageType;
+
+    StorageType storage;
+    ResultCode result_code;
+#if _DEBUG
+    // The purpose of this pointer is to aid inspecting the type with a debugger, eliminating the
+    // need to cast `storage` to a pointer or pay attention to `result_code`.
+    const T* debug_ptr;
+#endif
+
+    void UpdateDebugPtr() {
+#if _DEBUG
+        debug_ptr = empty() ? nullptr : static_cast<const T*>(static_cast<const void*>(&storage));
+#endif
+    }
+
+    const T* GetPointer() const {
+        assert(!empty());
+        return static_cast<const T*>(static_cast<const void*>(&storage));
+    }
+
+    T* GetPointer() {
+        assert(!empty());
+        return static_cast<T*>(static_cast<void*>(&storage));
+    }
+};
+
+/**
+ * This function is a helper used to construct `ResultVal`s. It receives the arguments to construct
+ * `T` with and creates a success `ResultVal` contained the constructed value.
+ */
+template <typename T, typename... Args>
+ResultVal<T> MakeResult(Args&&... args) {
+    return ResultVal<T>::WithCode(RESULT_SUCCESS, std::forward<Args>(args)...);
+}
diff --git a/src/core/hle/service/fs_user.cpp b/src/core/hle/service/fs_user.cpp
index 2aec1a52a..435be5b5d 100644
--- a/src/core/hle/service/fs_user.cpp
+++ b/src/core/hle/service/fs_user.cpp
@@ -4,26 +4,24 @@
 
 #include "common/common.h"
 
-#include "fs_user.h"
 #include "common/string_util.h"
-#include "core/settings.h"
 #include "core/hle/kernel/archive.h"
+#include "core/hle/kernel/archive.h"
+#include "core/hle/result.h"
+#include "core/hle/service/fs_user.h"
+#include "core/settings.h"
 
 ////////////////////////////////////////////////////////////////////////////////////////////////////
 // Namespace FS_User
 
 namespace FS_User {
 
-// We currently return 0 for success and -1 for failure in cmd_buff[1].  -1 was chosen because it
-// puts all the sections of the http://3dbrew.org/wiki/Error_codes to something non-zero, to make
-// sure we don't mislead the application into thinking something worked.
-
 static void Initialize(Service::Interface* self) {
     u32* cmd_buff = Service::GetCommandBuffer();
 
     // TODO(Link Mauve): check the behavior when cmd_buff[1] isn't 32, as per
     // http://3dbrew.org/wiki/FS:Initialize#Request
-    cmd_buff[1] = 0;
+    cmd_buff[1] = RESULT_SUCCESS.raw;
 
     DEBUG_LOG(KERNEL, "called");
 }
@@ -59,14 +57,12 @@ static void OpenFile(Service::Interface* self) {
 
     DEBUG_LOG(KERNEL, "path=%s, mode=%d attrs=%d", file_path.DebugStr().c_str(), mode, attributes);
 
-    Handle handle = Kernel::OpenFileFromArchive(archive_handle, file_path, mode);
-    if (handle) {
-        cmd_buff[1] = 0;
-        cmd_buff[3] = handle;
+    ResultVal<Handle> handle = Kernel::OpenFileFromArchive(archive_handle, file_path, mode);
+    cmd_buff[1] = handle.Code().raw;
+    if (handle.Succeeded()) {
+        cmd_buff[3] = *handle;
     } else {
         ERROR_LOG(KERNEL, "failed to get a handle for file %s", file_path.DebugStr().c_str());
-        // TODO(Link Mauve): check for the actual error values, this one was just chosen arbitrarily.
-        cmd_buff[1] = -1;
     }
 
     DEBUG_LOG(KERNEL, "called");
@@ -111,27 +107,27 @@ static void OpenFileDirectly(Service::Interface* self) {
 
     if (archive_path.GetType() != FileSys::Empty) {
         ERROR_LOG(KERNEL, "archive LowPath type other than empty is currently unsupported");
-        cmd_buff[1] = -1;
+        cmd_buff[1] = UnimplementedFunction(ErrorModule::FS).raw;
         return;
     }
 
     // TODO(Link Mauve): Check if we should even get a handle for the archive, and don't leak it
-    Handle archive_handle = Kernel::OpenArchive(archive_id);
-    if (!archive_handle) {
+    // TODO(yuriks): Why is there all this duplicate (and seemingly useless) code up here?
+    ResultVal<Handle> archive_handle = Kernel::OpenArchive(archive_id);
+    cmd_buff[1] = archive_handle.Code().raw;
+    if (archive_handle.Failed()) {
         ERROR_LOG(KERNEL, "failed to get a handle for archive");
-        // TODO(Link Mauve): Check for the actual error values, this one was just chosen arbitrarily
-        cmd_buff[1] = -1;
         return;
     }
+    // cmd_buff[2] isn't used according to 3dmoo's implementation.
+    cmd_buff[3] = *archive_handle;
 
-    Handle handle = Kernel::OpenFileFromArchive(archive_handle, file_path, mode);
-    if (handle) {
-        cmd_buff[1] = 0;
-        cmd_buff[3] = handle;
+    ResultVal<Handle> handle = Kernel::OpenFileFromArchive(*archive_handle, file_path, mode);
+    cmd_buff[1] = handle.Code().raw;
+    if (handle.Succeeded()) {
+        cmd_buff[3] = *handle;
     } else {
         ERROR_LOG(KERNEL, "failed to get a handle for file %s", file_path.DebugStr().c_str());
-        // TODO(Link Mauve): check for the actual error values, this one was just chosen arbitrarily.
-        cmd_buff[1] = -1;
     }
 
     DEBUG_LOG(KERNEL, "called");
@@ -243,14 +239,12 @@ static void OpenDirectory(Service::Interface* self) {
 
     DEBUG_LOG(KERNEL, "type=%d size=%d data=%s", dirname_type, dirname_size, dir_path.DebugStr().c_str());
 
-    Handle handle = Kernel::OpenDirectoryFromArchive(archive_handle, dir_path);
-    if (handle) {
-        cmd_buff[1] = 0;
-        cmd_buff[3] = handle;
+    ResultVal<Handle> handle = Kernel::OpenDirectoryFromArchive(archive_handle, dir_path);
+    cmd_buff[1] = handle.Code().raw;
+    if (handle.Succeeded()) {
+        cmd_buff[3] = *handle;
     } else {
         ERROR_LOG(KERNEL, "failed to get a handle for directory");
-        // TODO(Link Mauve): check for the actual error values, this one was just chosen arbitrarily.
-        cmd_buff[1] = -1;
     }
 
     DEBUG_LOG(KERNEL, "called");
@@ -282,19 +276,17 @@ static void OpenArchive(Service::Interface* self) {
 
     if (archive_path.GetType() != FileSys::Empty) {
         ERROR_LOG(KERNEL, "archive LowPath type other than empty is currently unsupported");
-        cmd_buff[1] = -1;
+        cmd_buff[1] = UnimplementedFunction(ErrorModule::FS).raw;
         return;
     }
 
-    Handle handle = Kernel::OpenArchive(archive_id);
-    if (handle) {
-        cmd_buff[1] = 0;
+    ResultVal<Handle> handle = Kernel::OpenArchive(archive_id);
+    cmd_buff[1] = handle.Code().raw;
+    if (handle.Succeeded()) {
         // cmd_buff[2] isn't used according to 3dmoo's implementation.
-        cmd_buff[3] = handle;
+        cmd_buff[3] = *handle;
     } else {
         ERROR_LOG(KERNEL, "failed to get a handle for archive");
-        // TODO(Link Mauve): check for the actual error values, this one was just chosen arbitrarily.
-        cmd_buff[1] = -1;
     }
 
     DEBUG_LOG(KERNEL, "called");
diff --git a/src/core/hle/service/gsp_gpu.cpp b/src/core/hle/service/gsp_gpu.cpp
index 66daded94..de1bd3f61 100644
--- a/src/core/hle/service/gsp_gpu.cpp
+++ b/src/core/hle/service/gsp_gpu.cpp
@@ -28,28 +28,23 @@ u32 g_thread_id = 1;            ///< Thread index into interrupt relay queue, 1
 
 /// Gets a pointer to a thread command buffer in GSP shared memory
 static inline u8* GetCommandBuffer(u32 thread_id) {
-    if (0 == g_shared_memory)
-        return nullptr;
-
-    return Kernel::GetSharedMemoryPointer(g_shared_memory,
-        0x800 + (thread_id * sizeof(CommandBuffer)));
+    ResultVal<u8*> ptr = Kernel::GetSharedMemoryPointer(g_shared_memory, 0x800 + (thread_id * sizeof(CommandBuffer)));
+    return ptr.ValueOr(nullptr);
 }
 
 static inline FrameBufferUpdate* GetFrameBufferInfo(u32 thread_id, u32 screen_index) {
-    if (0 == g_shared_memory)
-        return nullptr;
-
     _dbg_assert_msg_(GSP, screen_index < 2, "Invalid screen index");
 
     // For each thread there are two FrameBufferUpdate fields
     u32 offset = 0x200 + (2 * thread_id + screen_index) * sizeof(FrameBufferUpdate);
-    return (FrameBufferUpdate*)Kernel::GetSharedMemoryPointer(g_shared_memory, offset);
+    ResultVal<u8*> ptr = Kernel::GetSharedMemoryPointer(g_shared_memory, offset);
+    return reinterpret_cast<FrameBufferUpdate*>(ptr.ValueOr(nullptr));
 }
 
 /// Gets a pointer to the interrupt relay queue for a given thread index
 static inline InterruptRelayQueue* GetInterruptRelayQueue(u32 thread_id) {
-    return (InterruptRelayQueue*)Kernel::GetSharedMemoryPointer(g_shared_memory,
-        sizeof(InterruptRelayQueue) * thread_id);
+    ResultVal<u8*> ptr = Kernel::GetSharedMemoryPointer(g_shared_memory, sizeof(InterruptRelayQueue) * thread_id);
+    return reinterpret_cast<InterruptRelayQueue*>(ptr.ValueOr(nullptr));
 }
 
 static void WriteHWRegs(u32 base_address, u32 size_in_bytes, const u32* data) {
diff --git a/src/core/hle/service/hid_user.cpp b/src/core/hle/service/hid_user.cpp
index 5f6bf1eff..d29de1a52 100644
--- a/src/core/hle/service/hid_user.cpp
+++ b/src/core/hle/service/hid_user.cpp
@@ -34,10 +34,7 @@ static s16 next_circle_y = 0;
  * Gets a pointer to the PadData structure inside HID shared memory
  */
 static inline PadData* GetPadData() {
-    if (0 == shared_mem)
-        return nullptr;
-
-    return reinterpret_cast<PadData*>(Kernel::GetSharedMemoryPointer(shared_mem, 0));
+    return reinterpret_cast<PadData*>(Kernel::GetSharedMemoryPointer(shared_mem, 0).ValueOr(nullptr));
 }
 
 /**
diff --git a/src/core/hle/service/service.cpp b/src/core/hle/service/service.cpp
index abc8d5edb..fed2268a0 100644
--- a/src/core/hle/service/service.cpp
+++ b/src/core/hle/service/service.cpp
@@ -62,7 +62,7 @@ void Manager::DeleteService(const std::string& port_name) {
 
 /// Get a Service Interface from its Handle
 Interface* Manager::FetchFromHandle(Handle handle) {
-    return Kernel::g_object_pool.GetFast<Interface>(handle);
+    return Kernel::g_object_pool.Get<Interface>(handle);
 }
 
 /// Get a Service Interface from its port
diff --git a/src/core/hle/service/service.h b/src/core/hle/service/service.h
index 55aa84e83..136984b93 100644
--- a/src/core/hle/service/service.h
+++ b/src/core/hle/service/service.h
@@ -80,7 +80,7 @@ public:
      * @param wait Boolean wait set if current thread should wait as a result of sync operation
      * @return Result of operation, 0 on success, otherwise error code
      */
-    Result SyncRequest(bool* wait) override {
+    ResultVal<bool> SyncRequest() override {
         u32* cmd_buff = GetCommandBuffer();
         auto itr = m_functions.find(cmd_buff[0]);
 
@@ -91,7 +91,7 @@ public:
             // TODO(bunnei): Hack - ignore error
             u32* cmd_buff = Service::GetCommandBuffer();
             cmd_buff[1] = 0;
-            return 0;
+            return MakeResult<bool>(false);
         }
         if (itr->second.func == nullptr) {
             ERROR_LOG(OSHLE, "unimplemented function: port=%s, name=%s",
@@ -100,12 +100,12 @@ public:
             // TODO(bunnei): Hack - ignore error
             u32* cmd_buff = Service::GetCommandBuffer();
             cmd_buff[1] = 0;
-            return 0;
+            return MakeResult<bool>(false);
         }
 
         itr->second.func(this);
 
-        return 0; // TODO: Implement return from actual function
+        return MakeResult<bool>(false); // TODO: Implement return from actual function
     }
 
     /**
@@ -113,10 +113,10 @@ public:
      * @param wait Boolean wait set if current thread should wait as a result of sync operation
      * @return Result of operation, 0 on success, otherwise error code
      */
-    Result WaitSynchronization(bool* wait) override {
+    ResultVal<bool> WaitSynchronization() override {
         // TODO(bunnei): ImplementMe
         ERROR_LOG(OSHLE, "unimplemented function");
-        return 0;
+        return UnimplementedFunction(ErrorModule::OS);
     }
 
 protected:
diff --git a/src/core/hle/service/srv.cpp b/src/core/hle/service/srv.cpp
index df38bd93c..0e7fa9e3b 100644
--- a/src/core/hle/service/srv.cpp
+++ b/src/core/hle/service/srv.cpp
@@ -35,7 +35,7 @@ static void GetProcSemaphore(Service::Interface* self) {
 }
 
 static void GetServiceHandle(Service::Interface* self) {
-    Result res = 0;
+    ResultCode res = RESULT_SUCCESS;
     u32* cmd_buff = Service::GetCommandBuffer();
 
     std::string port_name = std::string((const char*)&cmd_buff[1], 0, Service::kMaxPortSize);
@@ -46,9 +46,9 @@ static void GetServiceHandle(Service::Interface* self) {
         DEBUG_LOG(OSHLE, "called port=%s, handle=0x%08X", port_name.c_str(), cmd_buff[3]);
     } else {
         ERROR_LOG(OSHLE, "(UNIMPLEMENTED) called port=%s", port_name.c_str());
-        res = -1;
+        res = UnimplementedFunction(ErrorModule::SRV);
     }
-    cmd_buff[1] = res;
+    cmd_buff[1] = res.raw;
 }
 
 const Interface::FunctionInfo FunctionTable[] = {
diff --git a/src/core/hle/svc.cpp b/src/core/hle/svc.cpp
index 3a06d6765..87d768856 100644
--- a/src/core/hle/svc.cpp
+++ b/src/core/hle/svc.cpp
@@ -16,6 +16,7 @@
 #include "core/hle/kernel/thread.h"
 
 #include "core/hle/function_wrappers.h"
+#include "core/hle/result.h"
 #include "core/hle/service/service.h"
 
 ////////////////////////////////////////////////////////////////////////////////////////////////////
@@ -86,18 +87,22 @@ static Result ConnectToPort(Handle* out, const char* port_name) {
 
 /// Synchronize to an OS service
 static Result SendSyncRequest(Handle handle) {
+    // TODO(yuriks): ObjectPool::Get tries to check the Object type, which fails since this is a generic base Object,
+    // so we are forced to use GetFast and manually verify the handle.
+    if (!Kernel::g_object_pool.IsValid(handle)) {
+        return InvalidHandle(ErrorModule::Kernel).raw;
+    }
     Kernel::Object* object = Kernel::g_object_pool.GetFast<Kernel::Object>(handle);
 
     _assert_msg_(KERNEL, (object != nullptr), "called, but kernel object is nullptr!");
     DEBUG_LOG(SVC, "called handle=0x%08X(%s)", handle, object->GetTypeName().c_str());
 
-    bool wait = false;
-    Result res = object->SyncRequest(&wait);
-    if (wait) {
+    ResultVal<bool> wait = object->SyncRequest();
+    if (wait.Succeeded() && *wait) {
         Kernel::WaitCurrentThread(WAITTYPE_SYNCH); // TODO(bunnei): Is this correct?
     }
 
-    return res;
+    return wait.Code().raw;
 }
 
 /// Close a handle
@@ -110,25 +115,25 @@ static Result CloseHandle(Handle handle) {
 /// Wait for a handle to synchronize, timeout after the specified nanoseconds
 static Result WaitSynchronization1(Handle handle, s64 nano_seconds) {
     // TODO(bunnei): Do something with nano_seconds, currently ignoring this
-    bool wait = false;
     bool wait_infinite = (nano_seconds == -1); // Used to wait until a thread has terminated
 
+    if (!Kernel::g_object_pool.IsValid(handle)) {
+        return InvalidHandle(ErrorModule::Kernel).raw;
+    }
     Kernel::Object* object = Kernel::g_object_pool.GetFast<Kernel::Object>(handle);
+    _dbg_assert_(KERNEL, object != nullptr);
 
     DEBUG_LOG(SVC, "called handle=0x%08X(%s:%s), nanoseconds=%lld", handle, object->GetTypeName().c_str(),
             object->GetName().c_str(), nano_seconds);
 
-    _assert_msg_(KERNEL, (object != nullptr), "called, but kernel object is nullptr!");
-
-    Result res = object->WaitSynchronization(&wait);
+    ResultVal<bool> wait = object->WaitSynchronization();
 
     // Check for next thread to schedule
-    if (wait) {
+    if (wait.Succeeded() && *wait) {
         HLE::Reschedule(__func__);
-        return 0;
     }
 
-    return res;
+    return wait.Code().raw;
 }
 
 /// Wait for the given handles to synchronize, timeout after the specified nanoseconds
@@ -143,20 +148,21 @@ static Result WaitSynchronizationN(s32* out, Handle* handles, s32 handle_count,
 
     // Iterate through each handle, synchronize kernel object
     for (s32 i = 0; i < handle_count; i++) {
-        bool wait = false;
+        if (!Kernel::g_object_pool.IsValid(handles[i])) {
+            return InvalidHandle(ErrorModule::Kernel).raw;
+        }
         Kernel::Object* object = Kernel::g_object_pool.GetFast<Kernel::Object>(handles[i]);
 
-        _assert_msg_(KERNEL, (object != nullptr), "called handle=0x%08X, but kernel object "
-            "is nullptr!", handles[i]);
-
         DEBUG_LOG(SVC, "\thandle[%d] = 0x%08X(%s:%s)", i, handles[i], object->GetTypeName().c_str(),
             object->GetName().c_str());
 
-        Result res = object->WaitSynchronization(&wait);
+        // TODO(yuriks): Verify how the real function behaves when an error happens here
+        ResultVal<bool> wait_result = object->WaitSynchronization();
+        bool wait = wait_result.Succeeded() && *wait_result;
 
         if (!wait && !wait_all) {
             *out = i;
-            return 0;
+            return RESULT_SUCCESS.raw;
         } else {
             unlock_all = false;
         }
@@ -164,13 +170,13 @@ static Result WaitSynchronizationN(s32* out, Handle* handles, s32 handle_count,
 
     if (wait_all && unlock_all) {
         *out = handle_count;
-        return 0;
+        return RESULT_SUCCESS.raw;
     }
 
     // Check for next thread to schedule
     HLE::Reschedule(__func__);
 
-    return 0;
+    return RESULT_SUCCESS.raw;
 }
 
 /// Create an address arbiter (to allocate access to shared resources)
@@ -183,8 +189,8 @@ static Result CreateAddressArbiter(u32* arbiter) {
 
 /// Arbitrate address
 static Result ArbitrateAddress(Handle arbiter, u32 address, u32 type, u32 value, s64 nanoseconds) {
-    return Kernel::ArbitrateAddress(arbiter, static_cast<Kernel::ArbitrationType>(type), address,
-        value);
+    return Kernel::ArbitrateAddress(arbiter, static_cast<Kernel::ArbitrationType>(type),
+            address, value).raw;
 }
 
 /// Used to output a message on a debug hardware unit - does nothing on a retail unit
@@ -246,13 +252,16 @@ static u32 ExitThread() {
 
 /// Gets the priority for the specified thread
 static Result GetThreadPriority(s32* priority, Handle handle) {
-    *priority = Kernel::GetThreadPriority(handle);
-    return 0;
+    ResultVal<u32> priority_result = Kernel::GetThreadPriority(handle);
+    if (priority_result.Succeeded()) {
+        *priority = *priority_result;
+    }
+    return priority_result.Code().raw;
 }
 
 /// Sets the priority for the specified thread
 static Result SetThreadPriority(Handle handle, s32 priority) {
-    return Kernel::SetThreadPriority(handle, priority);
+    return Kernel::SetThreadPriority(handle, priority).raw;
 }
 
 /// Create a mutex
@@ -266,9 +275,8 @@ static Result CreateMutex(Handle* mutex, u32 initial_locked) {
 /// Release a mutex
 static Result ReleaseMutex(Handle handle) {
     DEBUG_LOG(SVC, "called handle=0x%08X", handle);
-    _assert_msg_(KERNEL, (handle != 0), "called, but handle is nullptr!");
-    Kernel::ReleaseMutex(handle);
-    return 0;
+    ResultCode res = Kernel::ReleaseMutex(handle);
+    return res.raw;
 }
 
 /// Get current thread ID
@@ -310,16 +318,14 @@ static Result DuplicateHandle(Handle* out, Handle handle) {
 
 /// Signals an event
 static Result SignalEvent(Handle evt) {
-    Result res = Kernel::SignalEvent(evt);
     DEBUG_LOG(SVC, "called event=0x%08X", evt);
-    return res;
+    return Kernel::SignalEvent(evt).raw;
 }
 
 /// Clears an event
 static Result ClearEvent(Handle evt) {
-    Result res = Kernel::ClearEvent(evt);
     DEBUG_LOG(SVC, "called event=0x%08X", evt);
-    return res;
+    return Kernel::ClearEvent(evt).raw;
 }
 
 /// Sleep the current thread