emulator: answer OSC 10/11/12 colour queries for detached sessions#89
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emulator: answer OSC 10/11/12 colour queries for detached sessions#89nymph-ai wants to merge 1 commit into
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A program inside a detached rmux pane gets no answer when it queries the terminal's colours (OSC 10/11/12 with a `?` payload) — there is no attached terminal to forward the query to, and the emulator (which already impersonates the terminal for DA1/DA2/DSR/DECRQM/XTVERSION at dispatch.rs) parsed these OSC commands but never replied. Theme-detecting TUIs (e.g. Claude Code with theme=auto) silently fall back to the wrong palette. Answer the queries from the emulator, riding the existing parser reply buffer -> pane reader -> pty master write-back path: - `?` payload replies `OSC <n>;rgb:RRRR/GGGG/BBBB` terminated like the query (BEL/ST), matching the format rmux's own client-side theme parser (src/cli/terminal_theme.rs) expects. - set payloads are recorded so later queries round-trip the value, and still reach the ScreenWriter as before. - OSC 110/111/112 resets restore the defaults. - Defaults impersonate a conventional dark terminal (fg cccc/cccc/cccc, bg 0000/0000/0000) and are overridable per daemon via RMUX_DEFAULT_FOREGROUND / RMUX_DEFAULT_BACKGROUND / RMUX_DEFAULT_CURSOR_COLOUR. Tests: query replies for 10/11/12 with both terminators, set-then-query round-trip, 111 reset, writer passthrough for sets (RecordingWriter now records the colour calls).
shideneyu
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…plies install-windows.ps1 (PR #88 follow-up): force TLS 1.2 so Windows PowerShell 5.1 can reach GitHub releases, and make Fail throw instead of exit under irm|iex so a failed install no longer closes the user's interactive shell. verify-package-windows.ps1: check the installer's exit code instead of $? so a failing install.ps1 cannot pass the package gate. Ledger C-D50 (PR #89): record that answering OSC 10/11/12 colour queries from the emulator is an RMUX extension — probed tmux 3.7b leaves them unanswered in detached sessions.
shideneyu
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…ication DoS The OSC colour-query support (PR #89) stored an application-set colour verbatim (up to the 1 MiB input-buffer limit) and reflected it to every subsequent OSC 10/11/12 `?` query. Because the parser reply buffer is uncapped and drained only once per read batch (up to 4 MiB), a single pane output stream could set a ~1 MiB colour and then pack the rest of a batch with 7-byte queries, amplifying the stored value into hundreds of GB of replies before the buffer drains and OOM-ing the daemon that serves every session. Unlike the fixed-size DA1/DA2/DSR/XTVERSION replies, this reflected arbitrary application-controlled unbounded data, so the vector was new. - input/mod.rs: bound set_osc_colour to a 64-byte colour-spec length; a real X11 / rgb: / #rrggbb spec is far shorter, and an oversized value is not a colour, so it is left unstored and queries keep answering the prior or default value. The set is still forwarded to the writer (outer terminal) as before. - input/tests/osc_dcs_misc.rs: add a regression test asserting a ~1 MiB set followed by 100 queries keeps reply_buf under 100 KiB (was ~100 MiB) and still answers the default; the legitimate set-then-query round trip stays green.
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Problem
A program inside a detached rmux pane gets no answer when it queries the terminal's colours (
OSC 10/11/12with a?payload). The emulator already impersonates the attached terminal for DA1/DA2/DSR/DECRQM/XTVERSION (input/dispatch.rs), but the OSC colour commands were parsed and dropped (screen/writer.rsno-op stubs), so there was no reply at all.Theme-detecting TUIs mis-render as a result: e.g. Claude Code with
theme: "auto"queriesESC ]11;?at startup and, receiving nothing, silently falls back to the wrong palette variant (we hit this driving Claude Code inside detached rmux sessions — 256-color salmon instead of its truecolor brand orange).Change
Answer the queries from the emulator, riding the existing parser reply-buffer → pane reader → pty master write-back path (the same machinery as DA1):
?payload → replyOSC <n>;rgb:RRRR/GGGG/BBBB, terminated like the query (BEL vs ST) — the exact format rmux's own client-side theme parser (src/cli/terminal_theme.rs) produces and consumes.ScreenWriterunchanged.OSC 110/111/112resets restore defaults.rgb:cccc/cccc/cccconrgb:0000/0000/0000), overridable per daemon viaRMUX_DEFAULT_FOREGROUND/RMUX_DEFAULT_BACKGROUND/RMUX_DEFAULT_CURSOR_COLOUR.Tests
New unit tests beside the existing DA1/XTVERSION reply tests: query replies for all three slots with both terminators, set-then-query round-trip, reset behavior, and writer passthrough for set payloads (
RecordingWriternow records the colour calls).cargo test -p rmux-core: 913 passed;cargo test -p rmux-server pane_transcript: 18 passed; clippy/fmt clean.