From 2e8eba7dd0a0d3c15f9ed58e7a3b5282e47fa8ca Mon Sep 17 00:00:00 2001
From: Vincent Wei <vincent@minigui.org>
Date: Mon, 21 Mar 2022 17:48:03 +0800
Subject: [PATCH] fix a deadlock bug:
 https://github.com/VincentWei/minigui/issues/83

---
 src/include/dc.h          |  2 +-
 src/kernel/desktop-comm.c |  4 ++--
 src/kernel/desktop.c      | 12 ++++++++----
 src/newgdi/gdi.c          |  2 --
 4 files changed, 11 insertions(+), 9 deletions(-)

diff --git a/src/include/dc.h b/src/include/dc.h
index b636e93c..633213ea 100644
--- a/src/include/dc.h
+++ b/src/include/dc.h
@@ -93,7 +93,7 @@ typedef struct tagDC* PDC;
 # else /* not defined _MGSCHEMA_COMPOSITING */
 void __mg_lock_recalc_gcrinfo (PDC pdc);
 void __mg_unlock_gcrinfo (PDC pdc);
-#define LOCK_GCRINFO(pdc)       __mg_lock_recalc_gcrinfo (pdc)
+#define LOCK_GCRINFO(pdc)       if (dc_IsGeneralDC(pdc)) __mg_lock_recalc_gcrinfo (pdc)
 #define UNLOCK_GCRINFO(pdc)     if (dc_IsGeneralDC(pdc)) __mg_unlock_gcrinfo (pdc)
 # endif /* not defined _MGSCHEMA_COMPOSITING */
 
diff --git a/src/kernel/desktop-comm.c b/src/kernel/desktop-comm.c
index d0c7e424..9e742d6e 100644
--- a/src/kernel/desktop-comm.c
+++ b/src/kernel/desktop-comm.c
@@ -1403,7 +1403,7 @@ static LRESULT WindowMessageHandler(UINT message, PMAINWIN pWin, LPARAM lParam)
         else {
             from = 0;
         }
-     
+
         lock_zi_for_read (zi);
 
         from = __kernel_get_next_znode (zi, from);
@@ -1821,7 +1821,7 @@ static void dskRefreshAllWindow (const RECT* invrc)
         info.is_empty_invrc = TRUE;
 
 #ifdef _MGHAVE_MENU
-            dskForceCloseMenu ();
+    dskForceCloseMenu ();
 #endif
 
     SendMessage (HWND_DESKTOP, MSG_ERASEDESKTOP, 0,
diff --git a/src/kernel/desktop.c b/src/kernel/desktop.c
index 0cb5d723..5ba1efc7 100644
--- a/src/kernel/desktop.c
+++ b/src/kernel/desktop.c
@@ -611,7 +611,11 @@ static inline void unlock_zi_for_change (const ZORDERINFO* zi)
 
 static inline void lock_zi_for_read (const ZORDERINFO* zi)
 {
-    pthread_rwlock_rdlock(&((ZORDERINFO*)zi)->rwlock);
+    if (pthread_rwlock_rdlock(&((ZORDERINFO*)zi)->rwlock)) {
+        _ERR_PRINTF("Failed pthread_rwlock_rdlock: %s (%d)\n",
+                strerror(errno), errno);
+        abort();
+    }
 }
 
 static inline void unlock_zi_for_read (const ZORDERINFO* zi)
@@ -3641,6 +3645,9 @@ static int dskMoveWindow (int cli, int idx_znode, HDC memdc, const RECT* rcWin)
 
         do_for_all_znodes (&rcOld, zi, _cb_update_znode, ZT_ALL);
 
+        /* unlock zi for change ... */
+        unlock_zi_for_change (zi);
+
         if (nodes [0].flags & ZOF_IF_REFERENCE) {
             SendMessage (HWND_DESKTOP,
                             MSG_ERASEDESKTOP, 0, (LPARAM)&rcOld);
@@ -3680,9 +3687,6 @@ static int dskMoveWindow (int cli, int idx_znode, HDC memdc, const RECT* rcWin)
 
         update_client_window_rgn (nodes [idx_znode].cli,
                 nodes [idx_znode].hwnd);
-
-        /* unlock zi for change ... */
-        unlock_zi_for_change (zi);
     }
     else {
         lock_zi_for_change (zi);
diff --git a/src/newgdi/gdi.c b/src/newgdi/gdi.c
index 5e4c7055..684e2500 100644
--- a/src/newgdi/gdi.c
+++ b/src/newgdi/gdi.c
@@ -4349,8 +4349,6 @@ static void on_surface_changed_for_control (struct _travel_context* ctxt,
     RECT rc_surface, rc_minimal;
     PDC pdc = dc_HDC2PDC (ctrl->privCDC);
 
-    _WRN_PRINTF ("called\n");
-
     pdc->surface = ctxt->surface;
 
     if (pdc->surface != __gal_screen) {