Launcher: Consume Esc keypress when canceling shortcut copy to RAMCard

KBD was read but KBDSTRB wasn't hit to consume the keypress. Do it!

Also: leave high bit alone and adjust nearby compares.

Also also: leave some breadcrumbs in MGTK source about potentially
resolving similar issues once the GUI is active.

Fixes #868

Author: inexorabletash

RELEASE-NOTES.md

@@ -18,6 +18,7 @@ Project Page: https://github.com/a2stuff/a2d
 
 * Don't trust a partial copy of DeskTop on RAMCard; use DESKTOP.SYSTEM itself as a sentinel.
 * If running from a RAMCard, don't try to copy DeskTop to it.
+* Consume Esc keypress when canceling shortcut copy to RAMCard. ([#868](https://github.com/a2stuff/a2d/issues/868))
 
 ### DeskTop
 

res/notes/testplan.md

@@ -6,7 +6,8 @@
 
 * Without starting DeskTop, launch BASIC.SYSTEM. Set a prefix (e.g. "/RAM"). Invoke DESKTOP.SYSTEM with an absolute path (e.g. "-/A2.DESKTOP/DESKTOP.SYSTEM"). Verify that it starts correctly.
 * Move DeskTop into a subdirectory of a volume (e.g. "/VOL/A2D"). Without starting DeskTop, launch BASIC.SYSTEM. Set a prefix to a parent directory of desktop (e.g. "/VOL"). Invoke DESKTOP.SYSTEM with a relative path (e.g. "-A2D/DESKTOP.SYSTEM"). Verify that it starts correctly.
-* Configure a shortcut to copy to RAMCard "at boot". Launch DeskTop. Verify the shortcut's files were copied to RAMCard. Quit DeskTop. Re-launch DeskTop from the original startup volume. Eject the disk containing the shortcut. Run the shortcut. Verify that it launches correctly.
+* Configure a system with a RAMCard, and ensure DeskTop is configured to copy to RAMCard on startup. Configure a shortcut to copy to RAMCard "at boot". Launch DeskTop. Verify the shortcut's files were copied to RAMCard. Quit DeskTop. Re-launch DeskTop from the original startup volume. Eject the disk containing the shortcut. Run the shortcut. Verify that it launches correctly.
+* Configure a system with a RAMCard, and ensure DeskTop is configured to copy to RAMCard on startup. Configure a shortcut to copy to RAMCard "at boot". Launch DeskTop. While the shortcut's files are copying to RAMCard, press Esc. Verify that when the DeskTop appears the Apple menu is not activated.
 * Configure an Apple II+ system. Invoke DESKTOP.SYSTEM from a launcher (e.g. Bitsy Bye). Verify the launcher is restarted and does not crash or hang.
 * Configure an Apple IIe system with no card in the Aux slot. Invoke DESKTOP.SYSTEM from a launcher (e.g. Bitsy Bye). Verify the launcher is restarted and does not crash or hang.
 * Launch BASIC.SYSTEM. Save a file to /RAM. Invoke DESKTOP.SYSTEM. Verify that a warning is shown about /RAM not being empty. Press Esc. Verify that the ProDOS launcher is re-invoked. Verify that the file is still present in /RAM.

src/desktop.system/desktop.system.s

@@ -698,6 +698,7 @@ close:  MLI_CALL CLOSE, close_dstfile_params
 .proc CheckCancel
         lda     KBD
         bpl     ret
+        sta     KBDSTRB
         cmp     #$80|CHAR_ESCAPE
         beq     cancel
 ret:    rts
@@ -2108,15 +2109,14 @@ str_not_completed:
         sta     KBDSTRB
 loop:   lda     KBD
         bpl     loop
-        and     #CHAR_MASK
         sta     KBDSTRB
 
-        cmp     #kShortcutMonitor ; Easter Egg: If 'M', enter monitor
+        cmp     #$80|kShortcutMonitor ; Easter Egg: If 'M', enter monitor
         beq     monitor
-        cmp     #TO_LOWER(kShortcutMonitor)
+        cmp     #$80|TO_LOWER(kShortcutMonitor)
         beq     monitor
 
-        cmp     #CHAR_RETURN
+        cmp     #$80|CHAR_RETURN
         bne     loop
 
         jmp     FinishAndInvoke
@@ -2369,10 +2369,9 @@ done:   rts
 :       lda     KBD
         bpl     :-
         sta     KBDSTRB
-        and     #CHAR_MASK
-        cmp     #CHAR_ESCAPE
+        cmp     #$80|CHAR_ESCAPE
         beq     done
-        cmp     #CHAR_RETURN
+        cmp     #$80|CHAR_RETURN
         bne     :-
 done:   rts
 .endproc ; WaitEnterEscape

src/mgtk/mgtk.s

@@ -4812,6 +4812,8 @@ reset_desktop:
         jsr     SaveParamsAndStack
         jsr     SetDesktopPort
 
+        ;; TODO: Consider clearing `KBDSTRB` to avoid lingering keypresses.
+
         ;; Fills the desktop background on startup (menu left black)
         MGTK_CALL MGTK::SetPattern, desktop_pattern
         MGTK_CALL MGTK::PaintRect, desktop_mapinfo+MGTK::MapInfo::maprect
@@ -5377,16 +5379,18 @@ eventbuf:
 
         .res    kEventBufSize*MGTK::short_event_size
 
-
 .proc FlushEventsImpl
         php
         sei
         lda     #0
         sta     eventbuf_tail
         sta     eventbuf_head
+        ;; TODO: Consider clearing `KBDSTRB` to avoid a race where the
+        ;; keypress hasn't been seen yet when `FlushEvents` is called.
         plp
         rts
 .endproc ; FlushEventsImpl
+
         ;; called during PostEvent and a few other places
 .proc PutEvent
         lda     eventbuf_head