HLE: Revamp error handling throrough the HLE code

All service calls in the CTR OS return result codes indicating the
success or failure of the call. Previous to this commit, Citra's HLE
emulation of services and the kernel universally either ignored errors
or returned dummy -1 error codes.

This commit makes an initial effort to provide an infrastructure for
error reporting and propagation which can be use going forward to make
HLE calls accurately return errors as the original system. A few parts
of the code have been updated to use the new system where applicable.

One part of this effort is the definition of the `ResultCode` type,
which provides facilities for constructing and parsing error codes in
the structured format used by the CTR.

The `ResultVal` type builds on `ResultCode` by providing a container for
values returned by function that can report errors. It enforces that
correct error checking will be done on function returns by preventing
the use of the return value if the function returned an error code.

Currently this change is mostly internal since errors are still
suppressed on the ARM<->HLE border, as a temporary compatibility hack.
As functionality is implemented and tested this hack can be eventually
removed.

1 files changed, 19 insertions, 19 deletions

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;
 }
 
 /**