Scope decided with Captain Bob before implementation: ring buffer +
recall on today's full-screen vt100 grid, not also confining REPL text
to the 4.4o 640x480 box (that confinement stays open as its own future
item, not a third silent deferral). No keyboard input path exists yet
(M8 unstarted), so the trigger is two new FORTH words, SCROLL-BACK
( n -- ) / SCROLL-FWD ( n -- ), exercised via serial injection.
vt100.c gains a text-only 1000-line ring buffer (kmalloc'd, tens of KB
-- not pixel snapshots, which would be ~1000x larger for no benefit)
plus a shadow buffer mirroring the current screen. scroll_up() now
pushes evicted rows into the ring before the pixel scroll. History is
one continuous sequence (ring then shadow); scrolling always redraws
from that sequence -- no separate pixel-scroll path for scrollback,
decided up front to avoid retrofitting later.
New src/word_source/scroll_words.c (Module 31), thin wrappers over
console_fb_scroll_back()/_fwd() -> vt100_scroll_back()/_fwd(). Bug
caught during live testing: both words initially used an off-by-one
underflow check (dsp < 1) copied from a different, older dsp
convention elsewhere in this codebase; vm_pop() (which these words
actually call) uses dsp as a 0-based top-of-stack index, so the check
rejected every legitimate single-argument call. Fixed by removing the
separate precheck and relying on vm_pop()'s own guard.
Live-verified on all three architectures (exceeds this item's
amd64-minimum bar): generated 50+ lines via a FORTH loop, confirmed
SCROLL-BACK recovers correctly older content, and on amd64 confirmed
SCROLL-FWD returns to genuinely live state (not a frozen snapshot) by
showing the injected commands' own echo. Known limitation confirmed by
direct pixel measurement: redrawn lines lose their original SGR color
(not stored per-cell) -- text recovers exactly, color does not.
Three-arch verified: Failed: 0, dict-hashes identical across all
three (values changed correctly from prior items -- two new words
were added).
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
FABRIC.md: renumber Artemis-last boundary 4.4 -> 4.5, add new 4.4 REPL item
(console visual design scoped this session -- CANVAS is one shared region
above the REPL strip, 640x480 scroll box centered within it, stroke font,
ANSI color, VM-identity + ACL-identity prompt segments, ~1000-line
scrollback), linked to repl-mockup.png.
ROADMAP.md: mark M8 section OBSOLETE -- replaced by FABRIC.md 4.4, kept for
history only.
ttf_words.c: TTF-TEXT's y argument now Cartesian (origin bottom-left of the
physical framebuffer, y increasing upward) instead of raw framebuffer
coordinates, translated once via fb_height() - y. Verified via amd64
screendump (logs/20260811-070418/), text renders right-side-up with
increasing y moving up the screen.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Punch list §25 item 4.3.7e complete. New src/word_source/ttf_words.c
registers TTF-TEXT ( c-addr u x y size color -- ): lazily loads the v1
default font capsule + raster cache once, decodes UTF-8 (C
reimplementation mirroring capsules/fabric.4th's DECODE-UTF8 exactly),
looks up each glyph's cached bitmap, blits via fb_put_pixel, advances
the pen by the glyph's real hmtx advance width scaled to pixels.
Necessary plumbing: ttf_parse() now also locates hhea/hmtx, and
ttf_glyph_advance_width() reads a glyph's advance width -- required for
this item's own "proportional spacing correct" acceptance clause, no
advance-width data existed anywhere else in the parser. Verified in
tools/ttftest.c: A/a/0/space all read advance_width=600, correctly
uniform since JetBrainsMono-Regular.ttf is monospace.
(x,y) is raster pixel space (top-left origin, Y-down), deliberately not
the stroke font TEXT's Cartesian Y-up convention -- recorded explicitly
in ttf_words.h, not conflated.
Verified live, amd64, screendump: injected
S" Hi 4.3.7e!" 200 200 28 16777215 TTF-TEXT over a serial socket after
boot, no error, captured a screendump showing the string rendered
legibly with correct mixed-case/digit/punctuation glyphs and even
spacing. TTF-TEXT is this item's permanent deliverable, not a
throwaway probe. Compile-checked clean on all three architectures.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Punch list §25 item 4.3.5f complete. Keyboard-input slice done.
New KEY-EVENT ( -- keycode pressed -1 | 0 ) converges amd64's i8042,
riscv64's and aarch64's virtio-keyboard-pci behind one shape. Translation
needed is minimal: XT Set-1 make codes and Linux input keycodes are
numerically identical across the standard 84-key block (a documented
historical property of the Linux input subsystem, confirmed against this
host's own headers and this tree's own prior live observations), so amd64
needs two lines, riscv64/aarch64 need none. Verified live with a real
keypress on all three architectures: identical "-1 1 30" output everywhere.
Three-arch acceptance boot clean.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Punch list §25 item 4.3.5e complete.
Extended virtio_input.c with a GIC-routed interrupt path alongside 4.3.5c's
PLIC one -- same capability walk, feature negotiation, eventq handling
(confirming §27.5.1's prediction that these items would share most of the
driver). aarch64_irq_handler() dispatches to virtio_input_isr() before its
EOIR write, same claim-dispatch-complete ordering riscv64 uses. Verified
with a real QEMU sendkey keypress: exact KEY_A/press match, two real
interrupts serviced, identical result to riscv64. Found (not fixed) an
unrelated pre-existing bug: BYE's cold-reset path faults on aarch64,
discovered incidentally since nobody had exercised it from a monitored
session before. Three-arch acceptance boot clean.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Punch list §25 item 4.3.5c complete.
Amended from a nonexistent MMIO transport to PCI (matching the board's
actual virtio-blk-pci precedent). New virtio-input driver: eventq with
pre-posted buffers, PLIC source computed at runtime from PCI slot/pin
(derived live from this host's QEMU riscv64 DTB), mandatory ISR-status
read, PCI interrupt-disable-bit check. New VKBD-EVENT/VKBD-DEBUG FORTH
words. Verified with a real QEMU sendkey keypress: exact KEY_A/press
match, two real interrupts serviced, zero exceptions. Three-arch
acceptance boot clean.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Punch list §25 item 4.3.5 complete.
New ioapic.c/i8042.c drivers (MADT-derived I/O APIC base, no hardcoded
constants) plus a KBD-SCAN/KBD-DEBUG diagnostic word pair. Three real
bugs found and fixed en route, all blocking this item's own acceptance:
a fatal LAPIC spurious-vector crash (nothing had driven a real external
interrupt through the I/O APIC before), OVMF leaving the keyboard device
itself scanning-disabled (0xF4 fix), and isr.S's stub table only having
individually-numbered stubs through vector 32 -- everything above that,
including our IRQ1 vector 33, silently reported as vector 255 regardless
of which IDT slot actually fired. Verified live via QEMU sendkey against
KBD-SCAN: correct XT Set-1 make/break codes for two different keys.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Adds q48_reduce_angle() (range-reduce a signed Q48.16 angle into
[-PI_Q48, PI_Q48] via one integer division plus a bounded fix-up loop) and
q48_sin_approx/q48_cos_approx (Taylor series, terms n=3,5,7,9,11 for sin
and n=2,4,6,8,10 for cos, early exit below 10). Q.SIN/Q.COS registered as
FORTH words in q48_words.c, same pattern as Q.LOG/Q.EXP/Q.SQRT.
Found mid-implementation: this codebase has two independent Q48.16
implementations -- src/word_source/q48_16_words.c (hosted/vendored) and
src/starkernel/math/q48_16.c (kernel-only; the kernel build does not
compile the former at all). The hosted build linked fine after the first
pass; the kernel build failed with undefined references until the same
two functions were added to both .c files and both q48_16.h headers
(include/q48_16.h and include/starkernel/q48_16.h). Not fixed at the root
-- Q.LOG/Q.EXP/Q.SQRT already had this same four-file duplication,
unremarked until now -- just navigated correctly for this item.
Verified live on amd64 via serial injection: sin/cos at 0, +-pi/2, pi, and
3pi (range-reduction across multiple turns) all match expected values
within Taylor-series truncation error (<0.2%).
All three architectures boot clean to ok> with the DoE completing;
dict_hash identical across all three (0x291a660b05fa7b52).
FABRIC.md item 4.3.3a marked done with full acceptance evidence.
Adds Module 28 (framebuffer_words.c/.h): PLOT ( x y color -- ), FB-WIDTH,
FB-HEIGHT -- raw hardware-boundary C primitives, kernel-only, no-op on
hosted builds, same pattern as every other module.
Adds capsules/fabric.4th (blocks 4900-4902, mkcapsule --lint clean):
COS45/Z->DELTA/PROJECT/CART-Y/CART-PLOT -- the 45-degree cavalier
orthographic projection and Y-flip, in FORTH per the compose-in-FORTH-first
rule (this is policy, not hardware access).
Found and fixed a second real bug while live-testing CART-PLOT over the
serial socket: defining_word_variable() (defining_words.c) captured
vm->here as a VARIABLE's address with no alignment call first, while
vm_load_cell/vm_store_cell require 8-byte-aligned addresses. This capsule's
VARIABLE ZD landed misaligned (945) purely by chance of what preceded it;
other capsules' variables happened to land aligned by luck, not guarantee.
Real deviation from FORTH-83/ANS, which specifies VARIABLE reserves an
aligned cell. Fixed with vm_align(vm) before capturing addr -- ALIGN
already existed as a word but VARIABLE wasn't calling it.
Verified end-to-end on amd64 via manual serial injection + QEMU screendump:
plotted 4 marker points (origin, +100 X, +100 Y, +50 Z) and confirmed all
landed at hand-calculated raster coordinates, including the diagonal
up-right shift for the Z-axis point -- the projection math is correct, not
just non-crashing. fb/fabric-test-cart-plot.png. 4.3.1's corner diagnostic
still renders correctly in the same shot, confirming no regression.
All three architectures (amd64/aarch64/riscv64) boot clean to ok> with the
DoE completing; dict_hash identical across all three
(0xc7f9adf885e306d2), confirming parity is unaffected.
FABRIC.md item 4.3.3 marked done with full acceptance evidence.
No shift primitive existed anywhere in the vendored VM word set. Adds
both as FORTH-83-extension words next to INVERT, guarded against stack
underflow and out-of-range shift counts (u >= 64).
Their absence was masking a real bug: capsules/hermes/init.4th's
CH-MINT-ID (item 4.2) calls LSHIFT to pack a 64-bit channel ID, which
was silently tripping the capsule loader's forward-reference retry
logic and splicing CH-REQUEST's body into CH-MINT-ID's definition.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
The generic block subsystem (blk_format_or_load_disk) auto-reformatted
any disk lacking its own low-level 'STFR' header at attach time, before
Artemis's Forth-level BLANK/LithosAnanke/Unrecognized classification
ever ran -- so ART-HALT-UNRECOG's "Disk preserved" message was false.
Split detection from commit: an unrecognized/blank disk is now left
PROVISIONAL (geometry computed in memory only, all writes refused)
until explicitly confirmed via the new blk_subsys_confirm_format() /
BLK-CONFIRM-FORMAT primitive. Artemis calls it from ART-FORMAT and
ART-RESUME, never from ART-HALT-UNRECOG.
Verified on amd64/aarch64/riscv64: parity intact (identical dict_hash),
normal recognized-disk resume + persist-read unaffected, and a
regenerated disk/artemis-unrecognized-test.img (the old copy had itself
been silently corrupted by this exact bug) now stays byte-for-byte
identical across a halted boot on amd64 and riscv64.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
ABORT is documented and tested in this codebase as standard FORTH-79
behavior -- system_words_test.c:63: "Should clear stacks and return to
QUIT" -- meaning it should unwind all the way back to the outermost
interpreter loop, abandoning whatever's left of the current line/block.
The implementation only unwound one level: every place that checked
vm->abort_requested cleared it the instant it saw it, so it never
survived to propagate past the first nested frame.
This surfaced via Artemis's ART-HALT-UNRECOG (capsules/artemis/init.4th):
on an unrecognized disk it correctly printed "ARTEMIS HALT: unrecognized
disk content" and called ABORT, but WELCOME (the next line in the same
block) ran anyway, and Artemis announced ready to Hermes and joined the
fleet normally -- contradicting .claude/ARTEMIS.md's "Refuse to mount...
do not overwrite it" requirement. Root cause is general, not
Artemis-specific, and present identically in both the hosted and kernel
VM cores.
Fixed at every level execution can nest through, verified by exhaustively
grepping every !vm->error-gated continuation loop and adding the parallel
!vm->abort_requested check:
- execute_colon_word (src/vm.c, src/starkernel/vm/vm_core.c): stop
clearing the flag on return -- every colon-word call is a recursive
call to this same function, so leaving it set lets every enclosing
frame's own check also unwind.
- vm_interpret (src/vm.c, src/starkernel/vm/vm_core.c): stop parsing
further words in the current input string once the flag is set.
- exec_block_with_retry (src/starkernel/capsule/capsule_loader.c):
capsule birth's line-by-line block executor -- stop processing further
lines in the current block, but return 0 (not -1), so
capsule_exec_payload still loads later blocks in the same capsule
payload. Returning -1 here would have silently broken word definitions
in blocks that come after the aborting one for reasons unrelated to
why it aborted (concretely, Artemis's ART-PING/LOAD-DOE in blocks
4851/4852, which follow the entry block 4133).
- THRU and --> (src/word_source/block_words.c): stop processing further
blocks/lines in their own loops.
- DODOES (src/word_source/defining_words.c): the CREATE...DOES> runtime
has its own hand-rolled execution loop, separate from
execute_colon_word -- same bug class, same fix. Also guarded the
post-loop "if (vm->rsp < base_rsp) vm->rsp = base_rsp" clamp so it
doesn't fire on an abort exit -- ABORT's own reset_vm_state() already
set rsp; restoring it to base_rsp would have partially undone that.
- Both REPL loops (src/repl.c, src/starkernel/repl.c x2 call sites):
clear the flag after each line, mirroring the existing vm->error
pattern, so a mid-line abort doesn't silently freeze subsequent
interactive input.
Verified directly: ": AB-TEST 1 2 3 ABORT 999 . ; AB-TEST 42 . CR
777 . CR" -- 999 never prints (stops mid-colon-word), 42 never prints
(stops the rest of the same line), 777 prints fine (next line
unaffected). Artemis: WELCOME/"Artemis ready" no longer fires after the
halt message. No regression: all three architectures still show PASS:
persist-read, PASS: E2E msg flow, and matching dict_hash on the normal
(non-aborted) boot path; hosted test suite 965 passed / 0 failed.
Known follow-up, not fixed here (see memory for details): Artemis still
announces ready to Hermes via a separate call path (CD-INIT, block 4141)
that never went through capsule_exec_payload's block chain in the first
place, and the disk file still picks up incidental writes even on a
correctly-halted boot -- likely generic block-subsystem housekeeping,
not traced yet.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Addresses items #1 (partial) and #2 of
docs/working/archive/session-logs/2026-07-24-punch-list.md.
docs/lithosananke/hosted-acceptance-test/README.md:
- riscv64 leg used riscv64-linux-gnu-gcc, which fails to build this tree
(nanosleep visibility under -std=c99). Replaced with the working
clang-18 --target=riscv64-linux-gnu --sysroot=/usr/riscv64-linux-gnu
invocation, verified end-to-end.
- All three arch sections referenced a -c "<script>" flag that has never
existed in cli.c/main.c. Corrected to the working
`echo "..." | starforth -s` pattern, verified on all three architectures.
- Updated Prerequisites: qemu-user alone is sufficient (guest binaries are
static; qemu-user-static provides static *emulators*, not required here).
Source fixes (ported from the old pre-split monorepo's master, commit
4db9946a, where they were made but never carried over to this line):
- src/math_portable.c: `-100LL << 16` is UB (shifting a negative value)
under clang's -Wshift-negative-value; changed to `-(100LL << 16)`.
- src/physics_pipelining_metrics.c: removed dead q48_mul_q48()
(-Wunused-function under clang; GCC doesn't flag this by default).
- src/word_source/editor_words.c: removed dead set_scr() (same reason).
These three were required just to get the documented clang build to
compile at all. The punch list's higher-severity item — a genuine
SIGSEGV-causing register-reuse hazard in vm_pop_asm/vm_rpop_asm
(include/vm_asm_opt_riscv64.h) — is intentionally NOT included here; it's
a separate, more careful change and isn't required for this build to
succeed (latent only under clang; this repo's kernel build uses GCC).
Verified: all three hosted builds compile and run correctly (amd64
native, aarch64 via qemu-aarch64, riscv64 via qemu-riscv64), each
printing "3 Goodbye!" for the piped `1 2 + . BYE` script. All three
Makefile.starkernel builds (amd64/aarch64/riscv64) still compile cleanly
with these shared vendored-source changes.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
