From d0284e943da4ca2cb78b62aa0663cfb7a191c777 Mon Sep 17 00:00:00 2001
From: "Dr. Chat" <arkolbed@gmail.com>
Date: Fri, 11 Dec 2015 19:51:47 -0600
Subject: [PATCH] XSemaphore Save/Restore

---
 src/xenia/kernel/xobject.cc    |  2 +-
 src/xenia/kernel/xsemaphore.cc | 50 ++++++++++++++++++++++++++++++++++
 src/xenia/kernel/xsemaphore.h  |  5 ++++
 3 files changed, 56 insertions(+), 1 deletion(-)

diff --git a/src/xenia/kernel/xobject.cc b/src/xenia/kernel/xobject.cc
index 50fb69944..d6fc3398a 100644
--- a/src/xenia/kernel/xobject.cc
+++ b/src/xenia/kernel/xobject.cc
@@ -143,7 +143,7 @@ object_ref<XObject> XObject::Restore(KernelState* kernel_state, Type type,
     case kTypeNotifyListener:
       return NotifyListener::Restore(kernel_state, stream);
     case kTypeSemaphore:
-      break;
+      return XSemaphore::Restore(kernel_state, stream);
     case kTypeSession:
       break;
     case kTypeSocket:
diff --git a/src/xenia/kernel/xsemaphore.cc b/src/xenia/kernel/xsemaphore.cc
index ff7a69ff0..c15658ad8 100644
--- a/src/xenia/kernel/xsemaphore.cc
+++ b/src/xenia/kernel/xsemaphore.cc
@@ -9,6 +9,9 @@
 
 #include "xenia/kernel/xsemaphore.h"
 
+#include "xenia/base/byte_stream.h"
+#include "xenia/base/logging.h"
+
 namespace xe {
 namespace kernel {
 
@@ -22,6 +25,7 @@ void XSemaphore::Initialize(int32_t initial_count, int32_t maximum_count) {
 
   CreateNative(sizeof(X_KSEMAPHORE));
 
+  maximum_count_ = maximum_count;
   semaphore_ = xe::threading::Semaphore::Create(initial_count, maximum_count);
 }
 
@@ -29,6 +33,7 @@ void XSemaphore::InitializeNative(void* native_ptr, X_DISPATCH_HEADER* header) {
   assert_false(semaphore_);
 
   auto semaphore = reinterpret_cast<X_KSEMAPHORE*>(native_ptr);
+  maximum_count_ = semaphore->limit;
   semaphore_ = xe::threading::Semaphore::Create(semaphore->header.signal_state,
                                                 semaphore->limit);
 }
@@ -39,5 +44,50 @@ int32_t XSemaphore::ReleaseSemaphore(int32_t release_count) {
   return previous_count;
 }
 
+bool XSemaphore::Save(ByteStream* stream) {
+  if (!SaveObject(stream)) {
+    return false;
+  }
+
+  // Get the free number of slots from the semaphore.
+  uint32_t free_count = 0;
+  while (
+      threading::Wait(semaphore_.get(), false, std::chrono::milliseconds(0)) ==
+      threading::WaitResult::kSuccess) {
+    free_count++;
+  }
+
+  uint32_t used_count = maximum_count_ - free_count;
+  XELOGD("XSemaphore %.8X (count %d/%d)", handle(), used_count, maximum_count_);
+
+  // Restore the semaphore back to its previous count.
+  semaphore_->Release(free_count, nullptr);
+
+  stream->Write(maximum_count_);
+  stream->Write(used_count);
+
+  return true;
+}
+
+object_ref<XSemaphore> XSemaphore::Restore(KernelState* kernel_state,
+                                           ByteStream* stream) {
+  auto sem = new XSemaphore(nullptr);
+  sem->kernel_state_ = kernel_state;
+
+  if (!sem->RestoreObject(stream)) {
+    return nullptr;
+  }
+
+  sem->maximum_count_ = stream->Read<uint32_t>();
+  auto initial_count = stream->Read<uint32_t>();
+  XELOGD("XSemaphore %.8X (count %d/%d)", sem->handle(), initial_count,
+         sem->maximum_count_);
+
+  sem->semaphore_ =
+      threading::Semaphore::Create(initial_count, sem->maximum_count_);
+
+  return object_ref<XSemaphore>(sem);
+}
+
 }  // namespace kernel
 }  // namespace xe
diff --git a/src/xenia/kernel/xsemaphore.h b/src/xenia/kernel/xsemaphore.h
index 6dbd4f5d6..3cfdc6bf7 100644
--- a/src/xenia/kernel/xsemaphore.h
+++ b/src/xenia/kernel/xsemaphore.h
@@ -38,8 +38,13 @@ class XSemaphore : public XObject {
     return semaphore_.get();
   }
 
+  bool Save(ByteStream* stream) override;
+  static object_ref<XSemaphore> Restore(KernelState* kernel_state,
+                                        ByteStream* stream);
+
  private:
   std::unique_ptr<xe::threading::Semaphore> semaphore_;
+  uint32_t maximum_count_ = 0;
 };
 
 }  // namespace kernel