Make Emacs build with Xfixes support on old versions of the library

* src/xterm.c (xfixes_toggle_visible_pointer):
(x_toggle_visible_pointer):
(XTtoggle_invisible_pointer, x_term_init): Disable code
requiring fixes 4.0 or later when the fixes library is older.
* src/xterm.h: Define missing types needed by other extensions
when the fixes library is too old.
* configure.ac: Allow building with any version of the Xfixes
extension library.

configure.ac

@@ -4704,7 +4704,7 @@ AC_SUBST([XINERAMA_LIBS])
 ### Use Xfixes (-lXfixes) if available
 HAVE_XFIXES=no
 if test "${HAVE_X11}" = "yes"; then
-  XFIXES_REQUIRED=4.0.0
+  XFIXES_REQUIRED=1.0.0
   XFIXES_MODULES="xfixes >= $XFIXES_REQUIRED"
   EMACS_CHECK_MODULES([XFIXES], [$XFIXES_MODULES])
   if test $HAVE_XFIXES = no; then

src/xterm.c

@@ -11578,7 +11578,7 @@ x_new_focus_frame (struct x_display_info *dpyinfo, struct frame *frame)
   x_frame_rehighlight (dpyinfo);
 }
 
-#ifdef HAVE_XFIXES
+#if defined HAVE_XFIXES && XFIXES_VERSION >= 40000
 
 /* True if the display in DPYINFO supports a version of Xfixes
    sufficient for pointer blanking.  */
@@ -11590,11 +11590,12 @@ x_fixes_pointer_blanking_supported (struct x_display_info *dpyinfo)
 	  && dpyinfo->xfixes_major >= 4);
 }
 
-#endif /* HAVE_XFIXES */
+#endif /* HAVE_XFIXES && XFIXES_VERSION >= 40000 */
 
 /* Toggle mouse pointer visibility on frame F using the XFixes
    extension.  */
-#ifdef HAVE_XFIXES
+#if defined HAVE_XFIXES && XFIXES_VERSION >= 40000
+
 static void
 xfixes_toggle_visible_pointer (struct frame *f, bool invisible)
 
@@ -11605,6 +11606,7 @@ xfixes_toggle_visible_pointer (struct frame *f, bool invisible)
     XFixesShowCursor (FRAME_X_DISPLAY (f), FRAME_X_WINDOW (f));
   f->pointer_invisible = invisible;
 }
+
 #endif /* HAVE_XFIXES */
 
 /* Create invisible cursor on the X display referred by DPYINFO.  */
@@ -11653,7 +11655,7 @@ x_toggle_visible_pointer (struct frame *f, bool invisible)
   if (dpyinfo->invisible_cursor == None)
     dpyinfo->invisible_cursor = make_invisible_cursor (dpyinfo);
 
-#ifndef HAVE_XFIXES
+#if !defined HAVE_XFIXES || XFIXES_VERSION < 40000
   if (dpyinfo->invisible_cursor == None)
     invisible = false;
 #else
@@ -11686,7 +11688,7 @@ static void
 XTtoggle_invisible_pointer (struct frame *f, bool invisible)
 {
   block_input ();
-#ifdef HAVE_XFIXES
+#if defined HAVE_XFIXES && XFIXES_VERSION >= 40000
   if (FRAME_DISPLAY_INFO (f)->fixes_pointer_blanking
       && x_fixes_pointer_blanking_supported (FRAME_DISPLAY_INFO (f)))
     xfixes_toggle_visible_pointer (f, invisible);
@@ -30327,7 +30329,7 @@ x_term_init (Lisp_Object display_name, char *xrm_option, char *resource_name)
 				   1, 0, 1);
 
   dpyinfo->invisible_cursor = make_invisible_cursor (dpyinfo);
-#ifdef HAVE_XFIXES
+#if defined HAVE_XFIXES && XFIXES_VERSION >= 40000
   dpyinfo->fixes_pointer_blanking = egetenv ("EMACS_XFIXES");
 #endif
 

src/xterm.h

@@ -21,6 +21,22 @@ along with GNU Emacs.  If not, see <https://www.gnu.org/licenses/>.  */
 #define XTERM_H
 
 #include <X11/Xlib.h>
+
+#ifdef HAVE_XFIXES
+#include <X11/extensions/Xfixes.h>
+
+#if defined HAVE_XINPUT2 && XFIXES_MAJOR < 5
+/* XI2 headers need PointerBarrier, which is not defined in old
+   versions of the fixes library.  Define that type here.  */
+typedef XID PointerBarrier;
+#endif
+#if defined HAVE_XCOMPOSITE && XFIXES_MAJOR < 2
+/* Recent Composite headers need XserverRegion, which is not defined
+   in old versions of the fixes library.  Define that type here.  */
+typedef XID XserverRegion;
+#endif
+#endif
+
 #include <X11/cursorfont.h>
 
 /* Include Xutil.h after keysym.h to work around a bug that prevents
@@ -406,7 +422,7 @@ struct x_display_info
      Unused if this display supports Xfixes extension.  */
   Cursor invisible_cursor;
 
-#ifdef HAVE_XFIXES
+#if defined HAVE_XFIXES && XFIXES_VERSION >= 40000
   /* Whether or not to use Xfixes for pointer blanking.  */
   bool fixes_pointer_blanking;
 #endif