D326 - A controller subsystem that stops at the guest, and says where

decided · 2026-08-27 · built after checking what could honestly be built

Asked for a controller system - configurable count, real pads, keyboard mapping - and for those inputs to reach the emulator so the shell could be tested by pressing its own button. Checking first split the work in two, and the split is the decision.

The host side is entirely buildable and is built. Buttons named by position rather than by glyph, because a keyboard has no glyphs and a host pad reports positions anyway - naming by symbol would mean translating twice, and it keeps vendor marks out of the tree (principle 2). Ports are configurable to four, each driven by nothing, the keyboard, or a gamepad; key names are text so the mapping does not carry a window toolkit into the input contract (principle 12).

The guest side stops at a structure nobody has measured. scePadReadState writes pad state into guest memory and nothing in this repository knows that layout - the same wall as sceSystemServiceReceiveEvent (D311). So host input is read, the shell takes its button, and what is left is not carried across the process boundary at all: there is nothing on the far side that could consume it, and building the transport first is speculation by principle 12's own test. orbistoun-input remains declarations only, as its own header already said.

The shell button is the reason the window owns input. The system's own button has to be seen by something that is not the title, and a worker reading a pad directly could never hold one button back. That is not a workaround for the process split - it is the argument for reading input on this side of it.

Tap and hold are separated in a pure type taking elapsed milliseconds, so every edge is an assertion: a hold fires while still held because that is the only feedback before letting go, it fires once rather than every frame, and a release after one is not also a tap. Each of those is a menu bug that would otherwise be found by holding a button until something looked wrong.

Verified by pressing it. Holding for 1.1s opened the power menu with "quit the title" correctly absent, because nothing was running.