Drop async_visible and async_iconified fields of struct frame.

This is possible because async input is gone; for details, see
http://lists.gnu.org/archive/html/emacs-devel/2012-12/msg00734.html.
* frame.h (struct frame): Remove async_visible and async_iconified
members, convert garbaged to unsigned bitfield.  Adjust comments.
(FRAME_SAMPLE_VISIBILITY): Remove.  Adjust all users.
(SET_FRAME_VISIBLE, SET_FRAME_ICONIFIED): New macros.
* frame.c, gtkutil.c, term.c, w32fns.c, window.c, xdisp.c:
Consistently use SET_FRAME_VISIBLE, SET_FRAME_ICONIFIED,
FRAME_VISIBLE_P and FRAME_ICONIFIED_P macros where appropriate.
* w32term.c: Ditto.
(w32_read_socket): Save iconified state to generate DEICONIFY_EVENT
properly.  Likewise for obscured.
* xterm.c: Ditto.
(handle_one_xevent): Save visible state go generate ICONIFY_EVENT
properly.
* nsterm.m: Ditto.
(windowDidDeminiaturize): Generate DEICONIFY_EVENT.

1 files changed, 29 insertions, 65 deletions

diff --git a/src/frame.h b/src/frame.h
index c2821066c8..c18b766207 100644
--- a/src/frame.h
+++ b/src/frame.h
@@ -353,46 +353,30 @@ struct frame
   unsigned int external_menu_bar : 1;
 #endif
 
-  /* visible is nonzero if the frame is currently displayed; we check
+  /* Next two bitfields are mutually exclusive.  They might both be
+     zero if the frame has been made invisible without an icon.  */
+
+  /* Nonzero if the frame is currently displayed; we check
      it to see if we should bother updating the frame's contents.
-     DON'T SET IT DIRECTLY; instead, use FRAME_SET_VISIBLE.
 
      Note that, since invisible frames aren't updated, whenever a
-     frame becomes visible again, it must be marked as garbaged.  The
-     FRAME_SAMPLE_VISIBILITY macro takes care of this.
+     frame becomes visible again, it must be marked as garbaged.
 
      On ttys and on Windows NT/9X, to avoid wasting effort updating
      visible frames that are actually completely obscured by other
      windows on the display, we bend the meaning of visible slightly:
-     if greater than 1, then the frame is obscured - we still consider
+     if equal to 2, then the frame is obscured - we still consider
      it to be "visible" as seen from lisp, but we don't bother
      updating it.  We must take care to garbage the frame when it
-     ceases to be obscured though.
-
-     iconified is nonzero if the frame is currently iconified.
-
-     Asynchronous input handlers should NOT change these directly;
-     instead, they should change async_visible or async_iconified, and
-     let the FRAME_SAMPLE_VISIBILITY macro set visible and iconified
-     at the next redisplay.
-
-     These should probably be considered read-only by everyone except
-     FRAME_SAMPLE_VISIBILITY.
-
-     These two are mutually exclusive.  They might both be zero, if the
-     frame has been made invisible without an icon.  */
+     ceases to be obscured though.  See SET_FRAME_VISIBLE below.  */
   unsigned visible : 2;
-  unsigned iconified : 1;
-
-  /* Let's not use bitfields for volatile variables.  */
 
-  /* Asynchronous input handlers change these, and
-     FRAME_SAMPLE_VISIBILITY copies them into visible and iconified.
-     See FRAME_SAMPLE_VISIBILITY, below.  */
-  volatile char async_visible, async_iconified;
+  /* Nonzero if the frame is currently iconified.  Do not
+     set this directly, use SET_FRAME_ICONIFIED instead.  */
+  unsigned iconified : 1;
 
   /* Nonzero if this frame should be redrawn.  */
-  volatile char garbaged;
+  unsigned garbaged : 1;
 
   /* True if frame actually has a minibuffer window on it.
      0 if using a minibuffer window that isn't on this frame.  */
@@ -711,7 +695,7 @@ typedef struct frame *FRAME_PTR;
 #else
 #define FRAME_EXTERNAL_MENU_BAR(f) 0
 #endif
-#define FRAME_VISIBLE_P(f) ((f)->visible != 0)
+#define FRAME_VISIBLE_P(f) (f)->visible
 
 /* Nonzero if frame F is currently visible but hidden.  */
 #define FRAME_OBSCURED_P(f) ((f)->visible > 1)
@@ -719,9 +703,10 @@ typedef struct frame *FRAME_PTR;
 /* Nonzero if frame F is currently iconified.  */
 #define FRAME_ICONIFIED_P(f) (f)->iconified
 
-#define FRAME_SET_VISIBLE(f,p) \
-  ((f)->async_visible = (p), FRAME_SAMPLE_VISIBILITY (f))
+/* Mark frame F as currently garbaged.  */
 #define SET_FRAME_GARBAGED(f) (frame_garbaged = 1, f->garbaged = 1)
+
+/* Nonzero if frame F is currently garbaged.  */
 #define FRAME_GARBAGED_P(f) (f)->garbaged
 
 /* Nonzero means do not allow splitting this frame's window.  */
@@ -866,39 +851,6 @@ typedef struct frame *FRAME_PTR;
 
 #define FRAME_MESSAGE_BUF_SIZE(f) (((int) FRAME_COLS (f)) * 4)
 
-/* Emacs's redisplay code could become confused if a frame's
-   visibility changes at arbitrary times.  For example, if a frame is
-   visible while the desired glyphs are being built, but becomes
-   invisible before they are updated, then some rows of the
-   desired_glyphs will be left marked as enabled after redisplay is
-   complete, which should never happen.  The next time the frame
-   becomes visible, redisplay will probably barf.
-
-   Currently, there are no similar situations involving iconified, but
-   the principle is the same.
-
-   So instead of having asynchronous input handlers directly set and
-   clear the frame's visibility and iconification flags, they just set
-   the async_visible and async_iconified flags; the redisplay code
-   calls the FRAME_SAMPLE_VISIBILITY macro before doing any redisplay,
-   which sets visible and iconified from their asynchronous
-   counterparts.
-
-   Synchronous code must use the FRAME_SET_VISIBLE macro.
-
-   Also, if a frame used to be invisible, but has just become visible,
-   it must be marked as garbaged, since redisplay hasn't been keeping
-   up its contents.
-
-   Note that a tty frame is visible if and only if it is the topmost
-   frame. */
-
-#define FRAME_SAMPLE_VISIBILITY(f) \
-  (((f)->async_visible && (f)->visible != (f)->async_visible) ? \
-   SET_FRAME_GARBAGED (f) : 0, \
-   (f)->visible = (f)->async_visible, \
-   (f)->iconified = (f)->async_iconified)
-
 #define CHECK_FRAME(x) \
   CHECK_TYPE (FRAMEP (x), Qframep, x)
 
@@ -932,12 +884,24 @@ typedef struct frame *FRAME_PTR;
 	block_input ();						\
 	if (hlinfo->mouse_face_mouse_frame)			\
 	  note_mouse_highlight (hlinfo->mouse_face_mouse_frame,	\
-				hlinfo->mouse_face_mouse_x,     \
-				hlinfo->mouse_face_mouse_y);    \
+				hlinfo->mouse_face_mouse_x,	\
+				hlinfo->mouse_face_mouse_y);	\
 	unblock_input ();					\
       }								\
   } while (0)
 
+/* Set visibility of frame F, marking F as garbaged if needed.  */
+
+#define SET_FRAME_VISIBLE(f, v)				\
+  (((f)->visible == 0 || ((f)->visible == 2))		\
+   && ((v) == 1) ? SET_FRAME_GARBAGED (f) : 0,		\
+   (f)->visible = (eassert (0 <= (v) && (v) <= 2), (v)))
+
+/* Set iconify of frame F.  */
+
+#define SET_FRAME_ICONIFIED(f, i)			\
+  (f)->iconified = (eassert (0 <= (i) && (i) <= 1), (i))
+
 extern Lisp_Object Qframep, Qframe_live_p;
 extern Lisp_Object Qtty, Qtty_type;
 extern Lisp_Object Qtty_color_mode;