GPR678-4.01.0.patch

From 37ce1e2a5a232580794f450111729b3b270bc8ad Mon Sep 17 00:00:00 2001
From: David Allsopp <david.allsopp@metastack.com>
Date: Sat, 9 Jul 2016 23:04:43 +0100
Subject: [PATCH] Graphics.close_graph crashes 64-bit Windows ports

MPR3963 incorrectly fixed in 4.01.0. Closing the graphics window will
now cause calls to Graphics.wait_next_event to terminate (which was the
original MPR) and calling Graphics.close_graph no longer crashes the
64-bit runtime.
---
 otherlibs/win32graph/events.c | 18 ++++++++++++++----
 otherlibs/win32graph/open.c   |  1 -
 2 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/otherlibs/win32graph/events.c b/otherlibs/win32graph/events.c
index 6564283..aaedcfa 100755
--- a/otherlibs/win32graph/events.c
+++ b/otherlibs/win32graph/events.c
@@ -22,7 +22,8 @@ enum {
   EVENT_BUTTON_DOWN = 1,
   EVENT_BUTTON_UP = 2,
   EVENT_KEY_PRESSED = 4,
-  EVENT_MOUSE_MOTION = 8
+  EVENT_MOUSE_MOTION = 8,
+  EVENT_WINDOW_CLOSED = 16
 };
 
 struct event_data {
@@ -105,6 +106,10 @@ void caml_gr_handle_event(UINT msg, WPARAM wParam, LPARAM lParam)
     last_pos = lParam;
     caml_gr_enqueue_event(EVENT_MOUSE_MOTION, lParam, last_button, 0);
     break;
+  case WM_DESTROY:
+    // Release any calls to Graphics.wait_next_event
+    ReleaseSemaphore(caml_gr_queue_semaphore, 1, NULL);
+    break;
   }
 }
 
@@ -157,15 +162,20 @@ static value caml_gr_wait_event_blocking(int mask)
     /* Pop oldest event in queue */
     EnterCriticalSection(&caml_gr_queue_mutex);
     ev = caml_gr_queue[caml_gr_head];
-    /* Queue should never be empty at this point, but just in case... */
+    /* Empty queue means the window was closed */
     if (QueueIsEmpty) {
-      ev.kind = 0;
+      ev.kind = EVENT_WINDOW_CLOSED;
     } else {
       caml_gr_head = (caml_gr_head + 1) % SIZE_QUEUE;
     }
     LeaveCriticalSection(&caml_gr_queue_mutex);
     /* Check if it matches */
   } while ((ev.kind & mask) == 0);
+
+  if (ev.kind == EVENT_WINDOW_CLOSED) {
+    gr_fail("graphic screen not opened", NULL);
+  }
+
   return caml_gr_wait_allocate_result(ev.mouse_x, ev.mouse_y, ev.button,
                                       ev.kind == EVENT_KEY_PRESSED,
                                       ev.key);
@@ -176,7 +186,7 @@ CAMLprim value caml_gr_wait_event(value eventlist) /* ML */
   int mask, poll;
 
   gr_check_open();
-  mask = 0;
+  mask = EVENT_WINDOW_CLOSED;
   poll = 0;
   while (eventlist != Val_int(0)) {
     switch (Int_val(Field(eventlist, 0))) {
diff --git a/otherlibs/win32graph/open.c b/otherlibs/win32graph/open.c
index 016e52e..15c029a 100644
--- a/otherlibs/win32graph/open.c
+++ b/otherlibs/win32graph/open.c
@@ -104,7 +104,6 @@ static LRESULT CALLBACK GraphicsWndProc(HWND hwnd,UINT msg,WPARAM wParam,
                 // End application
         case WM_DESTROY:
                 ResetForClose(hwnd);
-		gr_check_open();
                 break;
         }
         caml_gr_handle_event(msg, wParam, lParam);
-- 
2.6.2.windows.1

diff -Naur a/patches/gpr#678.patched b/patches/gpr#678.patched
--- a/patches/gpr#678.patched	1970-01-01 01:00:00.000000000 +0100
+++ b/patches/gpr#678.patched	2016-07-05 13:54:02.412191200 +0100
@@ -0,0 +1 @@
+Applied