From c2c29af95981a9b60cba9fa92c47be3870409a65 Mon Sep 17 00:00:00 2001
From: jj <jj@jj>
Date: Mon, 25 Jun 2012 19:16:35 +0200
Subject: [PATCH] ruby: fix deadlock on df exit due to BEGIN_UNLOAD +
 Core.Suspend()

---
 plugins/ruby/README   | 3 ++-
 plugins/ruby/ruby.cpp | 4 +++-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/plugins/ruby/README b/plugins/ruby/README
index e4f22c71d..690e83ca0 100644
--- a/plugins/ruby/README
+++ b/plugins/ruby/README
@@ -116,7 +116,8 @@ To register ruby code to be run every graphic frame, use:
 To stop being called, use:
  df.onupdate_unregister handle
 
-The same mechanism is available for 'onstatechange'.
+The same mechanism is available for 'onstatechange', but the
+SC_BEGIN_UNLOAD event is not propagated to the ruby handler.
 
 
 C++ object manipulation
diff --git a/plugins/ruby/ruby.cpp b/plugins/ruby/ruby.cpp
index d4271c54a..8ec6ac464 100644
--- a/plugins/ruby/ruby.cpp
+++ b/plugins/ruby/ruby.cpp
@@ -181,7 +181,9 @@ DFhackCExport command_result plugin_onstatechange ( color_ostream &out, state_ch
         SCASE(MAP_UNLOADED);
         SCASE(VIEWSCREEN_CHANGED);
         SCASE(CORE_INITIALIZED);
-        SCASE(BEGIN_UNLOAD);
+	// if we go through plugin_eval at BEGIN_UNLOAD, it'll
+	// try to get the suspend lock and deadlock at df exit
+	case SC_BEGIN_UNLOAD : return CR_OK;
 #undef SCASE
     }