From 9e179e66f2af41f9ea5794acef6210ffb486a22b Mon Sep 17 00:00:00 2001
From: Nick Briggs <nicholas.h.briggs@gmail.com>
Date: Thu, 8 Jul 2021 15:18:41 -0700
Subject: [PATCH] Call getXsignaldata() with XLocked set

getXsignaldata() can call additional Xlib procedures which could generate an I/O
interrupt.  To avoid deadlocks in Xlib, ensure that XLocked is set when
getXsignaldata() is called.
---
 inc/ldeXdefs.h | 13 +++++++------
 inc/xdefs.h    |  9 +++++----
 2 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/inc/ldeXdefs.h b/inc/ldeXdefs.h
index 9a702cd..8b145e4 100755
--- a/inc/ldeXdefs.h
+++ b/inc/ldeXdefs.h
@@ -13,15 +13,16 @@
 /************************************************************************/
 
 #ifdef LOCK_X_UPDATES
-#define XLOCK { XLocked++; /* printf("L"); fflush(stdout);*/}
-#define XUNLOCK(dsp)                           \
-  { XLocked--;/* printf("U"); fflush(stdout);*/	\
-    if (XNeedSignal)				\
+#define XLOCK do { XLocked++; } while (0)
+#define XUNLOCK(dsp)				\
+  do { 						\
+    if (XLocked == 1 && XNeedSignal)		\
       {						\
 	XNeedSignal = 0;			\
 	getXsignaldata(dsp);			\
-      };						\
-  }
+      };					\
+    XLocked--;					\
+  } while (0)
 #else
 #define XLOCK
 #define XUNLOCK
diff --git a/inc/xdefs.h b/inc/xdefs.h
index 1ebb96e..d87ae6e 100755
--- a/inc/xdefs.h
+++ b/inc/xdefs.h
@@ -38,14 +38,15 @@
 extern volatile sig_atomic_t XLocked;
 extern volatile sig_atomic_t XNeedSignal;
 
-#define XLOCK do { XLocked++; /* printf("L"); fflush(stdout);*/} while (0)
-#define XUNLOCK(dsp)					\
-  do { XLocked--;/* printf("U"); fflush(stdout);*/	\
-    if (XNeedSignal)				\
+#define XLOCK do { XLocked++; } while (0)
+#define XUNLOCK(dsp)				\
+  do { 						\
+    if (XLocked == 1 && XNeedSignal)		\
       {						\
 	XNeedSignal = 0;			\
 	getXsignaldata(dsp);			\
       };					\
+    XLocked--;					\
   } while (0)
 #else
 #define XLOCK