--- uae/src/include/xwin.h	2018/04/24 16:40:12	1.1.1.3
+++ uae/src/include/xwin.h	2018/04/24 16:45:08	1.1.1.5
@@ -15,35 +15,57 @@ extern xcolnr xcolors[4096];
 extern int buttonstate[3];
 extern int newmousecounters;
 extern int lastmx, lastmy;
+extern int ievent_alive;
 
-extern int graphics_setup(void);
-extern int graphics_init(void);
-extern void graphics_leave(void);
-extern void handle_events(void);
-extern void setup_brkhandler(void);
-
-extern void flush_line(int);
-extern void flush_block(int, int);
-extern void flush_screen(int, int);
-
-extern int debuggable(void);
-extern int needmousehack(void);
-extern void togglemouse(void);
-extern void LED(int);
-
-extern unsigned long doMask(int p, int bits, int shift);
-extern void setup_maxcol(int);
-extern void alloc_colors256(int (*)(int, int, int, xcolnr *));
-extern void alloc_colors64k(int, int, int, int, int, int);
-extern void setup_greydither(int bits, allocfunc_type allocfunc);
-extern void setup_greydither_maxcol(int maxcol, allocfunc_type allocfunc);
-extern void setup_dither(int bits, allocfunc_type allocfunc);
-extern void DitherLine(uae_u8 *l, uae_u16 *r4g4b4, int x, int y, uae_s16 len, int bits) ASM_SYM_FOR_FUNC("DitherLine");
+extern int graphics_setup (void);
+extern int graphics_init (void);
+extern void graphics_leave (void);
+extern void handle_events (void);
+extern void setup_brkhandler (void);
+
+extern void flush_line (int);
+extern void flush_block (int, int);
+extern void flush_screen (int, int);
+
+extern int lockscr (void);
+extern void unlockscr (void);
+
+extern int debuggable (void);
+extern int needmousehack (void);
+extern void togglemouse (void);
+extern void LED (int);
+
+extern int bits_in_mask (unsigned long mask);
+extern int mask_shift (unsigned long mask);
+extern unsigned long doMask (int p, int bits, int shift);
+extern unsigned long doMask256 (int p, int bits, int shift);
+extern void setup_maxcol (int);
+extern void alloc_colors256 (int (*)(int, int, int, xcolnr *));
+extern void alloc_colors64k (int, int, int, int, int, int);
+extern void setup_greydither (int bits, allocfunc_type allocfunc);
+extern void setup_greydither_maxcol (int maxcol, allocfunc_type allocfunc);
+extern void setup_dither (int bits, allocfunc_type allocfunc);
+extern void DitherLine (uae_u8 *l, uae_u16 *r4g4b4, int x, int y, uae_s16 len, int bits) ASM_SYM_FOR_FUNC("DitherLine");
 
 struct vidbuf_description
 {
-    char *bufmem; /* Pointer to either the video memory or an area as large which is used as a buffer. */
-    char *linemem; /* Pointer to a single line in memory to draw into. If NULL, use bufmem. */
+    /* The graphics code has a choice whether it wants to use a large buffer
+     * for the whole display, or only a small buffer for a single line.
+     * If you use a large buffer:
+     *   - set bufmem to point at it
+     *   - set linemem to 0
+     *   - if memcpy within bufmem would be very slow, i.e. because bufmem is
+     *     in graphics card memory, also set emergmem to point to a buffer 
+     *     that is large enough to hold a single line.
+     *   - implement flush_line to be a no-op.
+     * If you use a single line buffer:
+     *   - set bufmem and emergmem to 0
+     *   - set linemem to point at your buffer
+     *   - implement flush_line to copy a single line to the screen
+     */
+    char *bufmem;
+    char *linemem;
+    char *emergmem;
     int rowbytes; /* Bytes per row in the memory pointed at by bufmem. */
     int pixbytes; /* Bytes per pixel. */
     int width;
@@ -60,36 +82,3 @@ extern struct vidbuf_description gfxvidi
 /* For ports using tui.c, this should be built by graphics_setup(). */
 extern struct bstring *video_mode_menu;
 extern void vidmode_menu_selected(int);
-
-/* Some definitions that are useful for multithreaded setups. */
-
-/* If frame_do_semup is nonzero, custom.c will do a sem_post on frame_sem
- * the next time it checks the contents of inhibit_frame.  That way, a
- * thread set a bit in inhibit_frame and wait until custom.c has stopped
- * drawing.
- * gui_sem is currently unused.
- * ihf_sem protects modifications of inhibit_frame.
- */
-extern uae_sem_t frame_sem, gui_sem, ihf_sem;
-extern volatile int inhibit_frame;
-extern volatile int frame_do_semup;
-
-static __inline__ void set_inhibit_frame (int bit)
-{
-    uae_sem_wait (&ihf_sem);
-    inhibit_frame |= 1 << bit;
-    uae_sem_post (&ihf_sem);
-}
-static __inline__ void clear_inhibit_frame (int bit)
-{
-    uae_sem_wait (&ihf_sem);
-    inhibit_frame &= ~(1 << bit);
-    uae_sem_post (&ihf_sem);
-}
-static __inline__ void toggle_inhibit_frame (int bit)
-{
-    uae_sem_wait (&ihf_sem);
-    inhibit_frame ^= ~(1 << bit);
-    uae_sem_post (&ihf_sem);
-}
-