Include code in midend.c to sanitise streams of mouse events so that

back ends can be assured of always receiving them in a sensible
sequence (button-down, followed by zero or more drags, followed by
button-up, and never changing button in the middle of such a
sequence). I have a suspicion this issue was the cause of the
mysterious Pattern grid updates seen by Dan during testing last
night.

[originally from svn r5208]

1 files changed, 7 insertions, 0 deletions

diff --git a/puzzles.h b/puzzles.h
index 4de81a7..c80f69b 100644
--- a/puzzles.h
+++ b/puzzles.h
@@ -34,6 +34,13 @@ enum {
     CURSOR_DOWN_RIGHT
 };
 
+#define IS_MOUSE_DOWN(m) ( (unsigned)((m) - LEFT_BUTTON) <= \
+                               (unsigned)(RIGHT_BUTTON - LEFT_BUTTON))
+#define IS_MOUSE_DRAG(m) ( (unsigned)((m) - LEFT_DRAG) <= \
+                               (unsigned)(RIGHT_DRAG - LEFT_DRAG))
+#define IS_MOUSE_RELEASE(m) ( (unsigned)((m) - LEFT_RELEASE) <= \
+                               (unsigned)(RIGHT_RELEASE - LEFT_RELEASE))
+
 #define IGNOREARG(x) ( (x) = (x) )
 
 typedef struct frontend frontend;