slosh.git/src/screen.c, branch master

screen: commit a wide cell's tail to prev, or the diff leaves a hole

2026-09-03T18:32:05Z

A wide glyph's tail column is never painted or compared, and prev never learned it either. Overwrite the head later and the terminal blanks the tail cell -- but if that column's new content matches the stale prev, the diff skips it, leaving a one-cell hole where the glyph's second half was. Seen as a missing rule cell in a pane's top border after spawning a new tab: the old tab's centered title started with a wide glyph, the new tab's border put the rule back, and the tail column stayed blank.

Add competitive multiplayer support.

2026-09-02T12:51:02Z

Last input wins, canvas size is adjusted to active connection.

slosh: OSC 8 hyperlinks pass through the compositor

2026-08-20T21:23:07Z

lib-vt tracks a hyperlink per cell and slosh dropped every one of them: the client's terminal can only offer a link it was sent, so `ls --hyperlink`, gcc diagnostics and friends silently lost theirs inside the session. The link rides beside the cell -- cell_t is the shader ABI and a link is not a colour -- as a plane of ids into an interned URI table, append-only so an id in prev_link still means the same URI next frame (which is what lets the diff compare ids instead of strings), and capped so a hostile pane cannot grow it forever. URIs with control bytes are refused outright: they are emitted verbatim inside an OSC, and a control byte in one is a way to write escape sequences into the client's terminal. The diff wraps emitted runs in OSC 8, closes what it opens before the frame ends, and treats a link-only change as a change. Chrome painted over a link takes the link with it, so a frame, modal or float across a URL is never clickable with the pane's link; links survive scrollback with the text that carries them. Plain-text URLs stay the outer terminal's own matcher, with the catch documented in panes.md: under mouse capture Ghostty only offers links with shift added to the gesture (shift+cmd hover/click), shift being its capture escape. Wrapped URLs can never be regex-matched through a multiplexer -- rows repaint as hard lines -- which is exactly what OSC 8 links, passing through whole, are for. `snapshot format:"bytes"` returns the emitter's own output for a frame (a second call is the delta): the model and the bytes are two different things, and this codebase already paid once for asserting on one while the other was wrong.

slosh: rename the project from sl0ppty

2026-08-18T19:26:00Z

sl0p + pty was error-prone to type and the zero made it worse; slosh (slop + sh) is one syllable, impossible to typo, and slosh.foo is ours. Mechanical rename everywhere it appears: binary, env vars (SLOSH, SLOSH_SESSION, SLOSH_BIN, SLOSH_CONFIG), socket dir (/tmp/slosh-, $XDG_RUNTIME_DIR/slosh), config path (~/.config/slosh), header guards, src/sl0ppty.h -> src/slosh.h, contrib/sl0ppty-dev -> contrib/slosh-dev, the driving-slosh skill, docs and tests. The sl0ppi fork references and the sl0p theme stay: one is history, the other is the brand. The rename surfaced a latent bug in test_osc5577: the hello-reply answer always appeared on screen twice (ECHOCTL echo plus cat -v), but a seven-character implementation name happened to wrap the second copy across the 60-column boundary, so counting substrings in wrapped text found one and passed for the wrong reason. A five-character name moved the wrap and exposed it. The loop guard itself is correct -- with echo off before the request there is exactly one reply -- so the test now counts on de-wrapped text and tolerates the pane's own echo.

sl0ppty: the middle of a border is the button, not all of it

2026-08-18T13:24:25Z

Clicking a pane's border to split toward it is the right gesture and was the wrong target. A border is the longest thing on the screen and it sits between two things you did mean to click -- a title, a gap, the pane beyond it -- so reaching a cell too far changed the layout, and the top row was worse than the sides: clicking a pane's header to focus it split it upward. So the target shrank. Each side carries a *handle* of three to seven cells in the middle, and only the handle splits; the rest of the edge is the *rim*, which arms the guide and does nothing when pressed. Three is the floor the pane buttons already settled on for the reason written there -- a one-cell target is a thing you miss with a mouse -- and seven is the ceiling, because a third of a tall pane's border is most of that border again and brings the accidents back with it. Hover now answers two questions in two stages, because they are two questions. Anywhere on an edge, the edge goes heavy and the handle thickens by a cell into the pane: that says where the button is, which is the thing you can no longer infer. On the handle, the dashed boundary and the arrow as well: that says what the click will do. The hint follows the same split, so sweeping an edge neither draws a boundary nor offers a split you cannot get from where the pointer is. Three things this had to get right. **The thickened handle is registered, not just painted.** The guide adds the hit for the inner strip in the frame that draws it, and reads the outer rect back from the hit list rather than recomputing it, so there is one opinion about where the handle is (D6). A handle you can see and cannot click would be worse than either mistake alone. **The top row cannot put its handle in the middle.** The buttons own its right and a centred title -- the default -- owns exactly the middle. The title winning is the existing rule, and it is what keeps a double-click rename from splitting twice on its way, so the handle is placed last, in the widest run of cells the row has left and nearest the middle among equals. A row with nothing left offers no upward split; its other three edges are unaffected. Each handle cell is then painted only if the hit list still agrees it belongs to the handle, so a block never lands on a pane's name. **The row keeps the drag and loses the split.** `title:` takes no side now and `title::t` -- the handle -- carries one, which is why the press path reads the side out of the action instead of assuming it. Press-and-hold skips the dwell on a handle, where a press means something, rather than anywhere on an edge. Verified: `make retest`, 1801 checks, all green. Nine of them are new or rewritten: the two-stage guide, the caption belonging to the handle, the rim splitting nothing on any of the four sides, the top row's handle still splitting upward on a titled pane, and the rim of the top row not. Tests read the handle's cell out of the hit list (`Snapshot.handle`/`.rim`) rather than deriving the geometry, so a test cannot agree with a broken formula. Also checked by hand on a live session, which is where the placement rule earned itself: hovering the rim draws the heavy edge and the block and no dashed line, hovering the handle adds the line and the arrow, three clicks on pane headers split nothing, and on a pane titled `sl0ppty` the top handle lands to the right of the title and left of the buttons -- `drag to move · click to split up` at x=42, `drag to move` either side of it.

sl0ppty: clang-format the tree

2026-08-17T12:22:38Z

The bumpy one. `make fmt` over every `.c` and `.h` outside `vendor/`: 32 files, 1,843 lines rewritten, no behaviour changed. Nothing here is worth reading -- the next commit adds it to `.git-blame-ignore-revs` so `git blame` walks past it. Two thirds of it is alignment the formatter now owns: trailing comments in a struct, continuation lines under a signature. The rest is the hand-packed tables opening up to one entry per line -- `ACTIONS`, `NAMED_KEYS`, `ACTION_HELP`. That is a real loss of density and a real gain in diffs: adding an action was a reflow of the block and is now one line. Anything worth keeping packed can be fenced with `// clang-format off`; nothing was, on the grounds that a table is the thing a formatter is for. **One change is not formatting.** `src/config.h` had three trailing comments glued onto one field: uint16_t hover_delay_ms; /* how long the pointer must rest to arm a guide */ /* how long an announcement stays up */ /* rows per wheel notch */ -- `toast_ms`'s and `scroll_lines`' comments, landed on their neighbour by an earlier edit, documenting the wrong things ever since. It is in this commit because it is what caught it: clang-format could not settle on that line, wrapping it one way and then re-indenting the wrap on a second pass, so `make fmt` was not idempotent. The comments are back where they belong and it is. Verified after the reformat, not before: `make clean && make all` is warning-free, `make retest` is 1801 checks green, and `make fmt` twice in a row changes nothing the second time. A formatter that alters behaviour would be worse than none, so the gate was the whole suite rather than a reading of the diff.

sl0ppty: measure chrome in columns, not characters

2026-08-15T16:44:07Z

Good catch: a two-column bell mark shifted the pane title row. Everything in app.c that positions chrome -- title budgets, button placement, the hit rects that have to agree with them -- came from a `cells()` that counted codepoints, and a glyph drawn in two columns was booked as one, so every glyph after it landed a column early. Widths now come from lib-vt's own table, via ghostty_unicode_grapheme_width. That is deliberately the same table the terminal uses for pane content, so chrome and content cannot disagree about how wide something is, and it is cluster-aware: an emoji with a variation selector is two codepoints and one glyph. A wide cell claims its right half as a tail (width 0), which the renderer already knew how to skip. HANDOVER said this was a known trap and to dump the actual cells before touching arithmetic, which is exactly how this went: the first assertion I wrote passed against a deliberately broken width function, because it measured the frame's right corner -- drawn at an absolute position, so it does not move -- rather than the columns the mark claims. The test now reads the mark's own colour runs and demands 1 column for a narrow mark and 2 for a wide one, and it fails when the width function is stubbed back to 1. Two things fell out on the way: ghostty_unicode_grapheme_width measures only the *first* cluster and returns the codepoints it consumed. My first loop ignored that and asked "did the width change when I added the next codepoint?", which concludes that an entire ASCII string is a single cluster -- the cheatsheet modal collapsed to ten columns wide with the text clipped. Use the return value. A cluster can also be longer than a cell holds: a ZWJ family emoji is 18 bytes against 16. Both the cell writer and the config's mark fields (now 32 bytes) clamp on a codepoint boundary, because snprintf cuts at a byte and half a codepoint is invalid UTF-8 -- which showed up as a decoder error in a test far from the cause, not as a short mark.

sl0ppty: rename from sl0ptty

2026-08-14T10:13:18Z

A pty is a pseudo-terminal, and that is what this multiplexes: the extra t was never standing for anything. Renaming now, while the only users are the people who typed the old name on purpose, is cheaper than renaming later. Mechanical, but not only cosmetic. The name is also the runtime contract, so this moves $SL0PTTY and $SL0PTTY_CONFIG, ~/.config/sl0ptty/config.kdl, the socket directory ($XDG_RUNTIME_DIR/sl0ptty, /tmp/sl0ptty-), and the identity string a program gets back from an OSC 5577 hello. A session left running under the old binary keeps its old socket directory and is invisible to the new one; there is no migration and it does not seem worth writing one. The sl0ppi fork keeps its name: it is a different thing, and D1 still points at it.

sl0ptty: M2 — server/client split, detach/reattach, control socket

2026-08-13T20:52:33Z

The session now outlives its client, which is the point: agents keep running while you are gone. The server owns the panes, the layout and the renderer; the client is a terminal in raw mode and a socket, forwarding bytes and painting what it is sent. It does not even decode input, so the decoder can change without redeploying clients. sl0ptty attach to 'main', creating it if nobody is home sl0ptty -s NAME a named session sl0ptty ls live sessions sl0ptty cmd LINE one control command C-a d detach Connections are not clients. A connection becomes the display client only by sending HELLO; control commands and liveness probes are just connections and never displace anybody. This was found the hard way, one hour after the server first ran: 'sl0ptty ls' kicked the attached client off, because ls connects to see whether a socket answers. That is precisely the fault that gave the zellij fork a 20-25% CLI failure rate, rebuilt and then fixed structurally. The regression runs 20 x (ls + control) against a live client and demands 0 failures and a client that can still type. cmd.c now holds the command vocabulary once, shared by the headless driver and the control socket, so a script written against one works against the other — 'sl0ptty cmd "snapshot text"' against a detached session prints its screen. tests/test_session.py: 18 checks over create, split, probe-resistance, detach, survival, drive-while-detached, reattach, displacement and cleanup. 123 checks green overall.

sl0ptty: M1 — layout tree, splits, focus, frames, and the hit list in use

2026-08-13T20:35:57Z

app_t owns the tree, focus, the prefix and what a key means; the interactive client and the headless driver are now both thin front ends over it, so there is exactly one implementation of every command. Layout is the pure function D6 promised: layout(tree, rect) recomputed every frame, remainder spread across children so nothing drifts, and splitting in a direction that already exists grows that split rather than nesting — three splits give three equal columns, not 1/2 + 1/4 + 1/4. Chrome: rounded frames, aspect-corrected gap, centred titles. The split button is budgeted BEFORE the title and hit-tested from the rect it was drawn in, which is the fix the fork needed four attempts to land. Every painted element registers (rect, action) as it is painted; a click is a lookup. Mouse into a pane is translated to pane-local coordinates. Three bugs the harness caught, none of which unit tests would have: - one click on the split button split twice: press *and* release both fired. Chrome now acts on press; forwarding to a pane still gets every event. - callbacks were registered as &fn, but the option is pointer-typed, so the stored 'callback' was a stack address. Any OSC 2 or DSR jumped into a dead frame. Now a hard segfault turned into two regression tests. - a keystroke that changed nothing still emitted a cursor hide/show pair. The cursor is hidden lazily now, so an idle frame costs zero bytes. 96 checks green in 6s (40 unit, 23 screen, 33 layout), plus 9 live.