From a550e112c3307e568309b2bc0c6e026494543e9b Mon Sep 17 00:00:00 2001
From: Pauli <suokkos@gmail.com>
Date: Tue, 3 Jul 2018 21:15:12 +0300
Subject: [PATCH] Allow temporary transfer of main logic thread ownership

Dependency to fix df-ai to work with the new CoreSuspender
---
 library/Core.cpp       | 20 ++++++++++++++++++++
 library/include/Core.h | 22 ++++++++++++++++++++++
 2 files changed, 42 insertions(+)

diff --git a/library/Core.cpp b/library/Core.cpp
index 20b2565ff..2bce4869b 100644
--- a/library/Core.cpp
+++ b/library/Core.cpp
@@ -108,6 +108,26 @@ struct MainThread {
 };
 }
 
+CoreSuspendReleaseMain::CoreSuspendReleaseMain()
+{
+    MainThread::suspend().unlock();
+}
+
+CoreSuspendReleaseMain::~CoreSuspendReleaseMain()
+{
+    MainThread::suspend().lock();
+}
+
+CoreSuspendClaimMain::CoreSuspendClaimMain()
+{
+    MainThread::suspend().lock();
+}
+
+CoreSuspendClaimMain::~CoreSuspendClaimMain()
+{
+    MainThread::suspend().unlock();
+}
+
 struct Core::Private
 {
     std::thread iothread;
diff --git a/library/include/Core.h b/library/include/Core.h
index f05e30f8a..dbe73621d 100644
--- a/library/include/Core.h
+++ b/library/include/Core.h
@@ -300,6 +300,8 @@ namespace DFHack
         friend class ServerConnection;
         friend class CoreSuspender;
         friend class CoreSuspenderBase;
+        friend struct CoreSuspendClaimMain;
+        friend struct CoreSuspendReleaseMain;
         ServerMain *server;
     };
 
@@ -412,5 +414,25 @@ namespace DFHack
         }
     };
 
+    /*!
+     * Temporary release main thread ownership to allow alternative thread
+     * implement DF logic thread loop
+     */
+    struct DFHACK_EXPORT CoreSuspendReleaseMain {
+        CoreSuspendReleaseMain();
+        ~CoreSuspendReleaseMain();
+    };
+
+    /*!
+     * Temporary claim main thread ownership. This allows caller to call
+     * Core::Update from a different thread than original DF logic thread if
+     * logic thread has released main thread ownership with
+     * CoreSuspendReleaseMain
+     */
+    struct DFHACK_EXPORT CoreSuspendClaimMain {
+        CoreSuspendClaimMain();
+        ~CoreSuspendClaimMain();
+    };
+
     using CoreSuspendClaimer = CoreSuspender;
 }