FABRIC-2.md §I.9: fix the terminal phantom-linebreak defect

Browse Source

console_ensure_line_start() (hal/console.c) used to emit its newline
immediately via a path that deliberately skipped the tx-byte counter, so
that sk_repl_idle()'s unconditional per-beat call to it (repl.c, ~1s idle
heartbeat) could force a real newline the REPL's own prompt-reanchor logic
never noticed -- the prompt was never reprinted, and the next real
keystroke echoed onto the now-blank line, indistinguishable from Enter
having already been pressed at a bare prompt. Root-caused in the previous
commit (704573b); this commit applies the fix per explicit go-ahead.

Fix: defer the newline instead of emitting it eagerly.
console_ensure_line_start() now only sets a flag (g_pending_line_close);
the newline is realized -- for real, and counted by g_console_tx_count
like any other output -- on the next actual console_putc() call, or
silently discarded via the new console_cancel_deferred_line_start() if the
caller decides nothing was actually printed. sk_repl_idle() captures
tx_before_idle right after its console_ensure_line_start() call and cancels
the deferred newline at both of its exit points when console_tx_count()
hasn't moved. A beat with nothing to report now leaves the console
untouched; a beat that does print still closes the dangling prompt line
first, properly counted this time. The pre-existing n > 0 mid-edit gate in
sk_console_readline() is untouched -- independent purpose, not the bug.

Verified via the mandatory foreground 3-arch QEMU acceptance boot
(clean qemu, amd64 -> aarch64 -> riscv64, one at a time): all three reached
(zuse) ok>, all echoed the first real input on the same log line as the
prompt rather than a fresh line, all shut down cleanly via BYE. amd64's log
additionally shows live human backspace-correction still glued to the same
prompt line. Logs: logs/20260905-015854 (amd64), logs/20260905-020248
(aarch64), logs/20260905-020552 (riscv64); logs/20260905-015813 is a
foreground-rule-violation retry killed and redone correctly, kept per this
project's "never delete logs/" convention.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019YcT3H2PQeyujrzjqS3Var

...

This commit is contained in:

Robert Allan James

2026-09-05 02:08:06 -04:00

co-authored by Claude Sonnet 5

parent 704573bdfc

commit 8edb95b65d

13 changed files with 27108 additions and 26 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download Patch File Download Diff File Expand all files Collapse all files

disk/artemis.img

BIN

Binary file not shown.