Files
LithosAnanake/proof/StarForth_Keyboard_Words.thy
T
Robert Allan James 1e76ebea97 proof/: add console-fabric word coverage (framebuffer/keyboard/scroll/ttf)
Stadium console fabric words (FABRIC.md items 4.3.3/4.3.5/4.3.7e/4.4q/
4.4v/4.4y). All four files gate their real hardware-touching bodies
behind __STARKERNEL__ (and, for keyboard, architecture too):

- StarForth_Framebuffer_Words.thy: PLOT/FB-WIDTH/FB-HEIGHT fully modelled
  for the hosted-build fallback (deterministic, no hardware dependency);
  kernel bodies (fb_put_pixel/fb_width/fb_height) deferred. Finding:
  FB-WIDTH/FB-HEIGHT have no overflow guard before pushing -- second
  instance of this class of bug after DECAY-RATE@.
- StarForth_Keyboard_Words.thy: all 6 words' non-kernel-or-wrong-arch
  fallback modelled (fixed constant pushes / no-op); third and fourth
  missing-overflow-guard instances. Real hardware polling
  (i8042/virtio-input) deferred.
- StarForth_Scroll_Words.thy / StarForth_TTF_Words.thy: both files gate
  registration itself behind __STARKERNEL__, so their words don't exist
  at all in a hosted build -- no fallback to model, sentinel-only.

Suite now 48 theories, confirmed green via a full clean rebuild (HOL-
Library cold-built in 15m18s after an accidental heap clear, StarForth
itself 33s).
2026-08-14 16:15:27 -04:00

106 lines
5.4 KiB
Plaintext

theory StarForth_Keyboard_Words
imports StarForth_Base
begin
(* =========================================================================
Mirrors: src/word_source/keyboard_words.c
Registers: KBD-SCAN KBD-DEBUG VKBD-EVENT VKBD-DEBUG KEY-EVENT ALT+TAB
Part of the Stadium console fabric work (FABRIC.md items 4.3.5/4.4v/
4.4y). All six words are registered UNCONDITIONALLY regardless of
build/arch, but every body is gated on `__STARKERNEL__` (and, for the
amd64-specific/riscv64-aarch64-specific pairs, the target architecture
too). Outside the matching kernel+arch combination, every one of these
six falls through to a fixed, hardware-independent fallback --
identically to framebuffer_words.c, and reachable the same way (a
plain hosted `make` build).
── Scope ─────────────────────────────────────────────────────────────
The fallback (non-kernel-or-wrong-arch) behaviour of all six words is
fully modelled: every one reduces to a fixed constant push (or, for
ALT+TAB, a true no-op) with NO capacity guard before pushing -- the
third and fourth instances of the missing-overflow-guard finding first
raised in physics_freeze_words.c's DECAY-RATE@ (KBD-SCAN/VKBD-EVENT/
VKBD-DEBUG/KEY-EVENT push 1-2 cells unconditionally; KBD-DEBUG pushes
2). The real (matching kernel+arch) hardware-polling bodies are NOT
modelled: i8042_pop_scancode/virtio_input_pop_event/
console_fb_toggle_graphics are all raw hardware/interrupt-state reads
with no vm_state counterpart, the same class of gap as every other
hardware-boundary word in this console-fabric group. `sk_key_event_poll`
is a small pure function (bit 7 of an XT scancode byte / a virtio-input
value field, both external to vm_state either way) -- its fallback
branch (`return 0`) is what's modelled here as part of KEY-EVENT's
fallback; its two hardware branches are not.
======================================================================== *)
(* ── KBD-SCAN ( -- c -1 | 0 ) : fallback pushes 0 ────────────────────────── *)
definition forth_kbd_scan_fallback :: "vm_state \<Rightarrow> vm_state" where
"forth_kbd_scan_fallback vm = vm\<lparr>data_stack := 0 # data_stack vm\<rparr>"
lemma kbd_scan_fallback_pushes_zero:
"data_stack (forth_kbd_scan_fallback vm) = 0 # data_stack vm"
by (simp add: forth_kbd_scan_fallback_def)
(* ── KBD-DEBUG ( -- isr_count spurious_count ) : fallback pushes 0 0 ─────── *)
definition forth_kbd_debug_fallback :: "vm_state \<Rightarrow> vm_state" where
"forth_kbd_debug_fallback vm = vm\<lparr>data_stack := 0 # 0 # data_stack vm\<rparr>"
lemma kbd_debug_fallback_pushes_zeros:
"data_stack (forth_kbd_debug_fallback vm) = 0 # 0 # data_stack vm"
by (simp add: forth_kbd_debug_fallback_def)
(* ── VKBD-EVENT ( -- code value -1 | 0 ) : fallback pushes 0 ────────────── *)
definition forth_vkbd_event_fallback :: "vm_state \<Rightarrow> vm_state" where
"forth_vkbd_event_fallback vm = vm\<lparr>data_stack := 0 # data_stack vm\<rparr>"
lemma vkbd_event_fallback_pushes_zero:
"data_stack (forth_vkbd_event_fallback vm) = 0 # data_stack vm"
by (simp add: forth_vkbd_event_fallback_def)
(* ── VKBD-DEBUG ( -- isr_count ) : fallback pushes 0 ─────────────────────── *)
definition forth_vkbd_debug_fallback :: "vm_state \<Rightarrow> vm_state" where
"forth_vkbd_debug_fallback vm = vm\<lparr>data_stack := 0 # data_stack vm\<rparr>"
lemma vkbd_debug_fallback_pushes_zero:
"data_stack (forth_vkbd_debug_fallback vm) = 0 # data_stack vm"
by (simp add: forth_vkbd_debug_fallback_def)
(* ── KEY-EVENT ( -- keycode pressed -1 | 0 ) : fallback pushes 0 ────────── *)
(* sk_key_event_poll's fallback branch (neither ARCH_AMD64 nor riscv64/
aarch64 under __STARKERNEL__) returns 0 without touching its out-params;
kbw_key_event's `else` branch then pushes a single 0. *)
definition forth_key_event_fallback :: "vm_state \<Rightarrow> vm_state" where
"forth_key_event_fallback vm = vm\<lparr>data_stack := 0 # data_stack vm\<rparr>"
lemma key_event_fallback_pushes_zero:
"data_stack (forth_key_event_fallback vm) = 0 # data_stack vm"
by (simp add: forth_key_event_fallback_def)
(* ── ALT+TAB ( -- ) : fallback is a true no-op ───────────────────────────── *)
definition forth_alt_tab_fallback :: "vm_state \<Rightarrow> vm_state" where
"forth_alt_tab_fallback vm = vm"
lemma alt_tab_fallback_identity: "forth_alt_tab_fallback vm = vm"
by (simp add: forth_alt_tab_fallback_def)
lemma alt_tab_kernel_not_modelled: True
\<comment> \<open>Kernel build: console_fb_toggle_graphics() -- console/framebuffer
mode-toggle state, no vm_state counterpart.\<close>
by simp
lemma keyboard_kernel_bodies_not_modelled: True
\<comment> \<open>All five hardware-polling words' real (kernel+matching-arch) bodies
-- i8042_pop_scancode/virtio_input_pop_event and their associated ISR
counters (g_i8042_isr_count/g_spurious_count/g_virtio_input_isr_count,
themselves file-scope C statics/externs) -- are not modelled. Same
class of gap as every hardware-boundary word in this group.\<close>
by simp
end