e04ca28812
Removes the "-unix" element and with it any trademark exposure to The
Open Group.
The split follows the ecosystem layout: SchOS is the system, and the
kernel has its own name. Kernel-identity strings are the only places
that take SchIFT -- uname(2) sysname, /proc/version, and the two licence
sentences that say "kernel" outright. That is what every Unix does here:
`uname -s` on Linux reports the kernel, not the distribution. Everything
a user reads as the product -- panic screen, boot menu, error prefixes,
docs, LICENSE, NOTICE -- is SchOS.
schunix.img is schos.img, the logo assets and the musl TLS patch are
renamed, and __SCHUNIX__ is __SCHOS__ (the define and the patch that
consumes it moved together).
Two things the rename broke, both found by the bootcheck suite:
- shmtest wrote "SCHUNIX-MMAP-OK" with a hardcoded length of 15 and
compared it back by hand-counted offsets (m[3]=='U', m[14]=='K').
The shorter marker left the write running two bytes past the literal
and the compare reading past the data, failing a file-backed mmap
that was working correctly. Now written and compared through one
constant with sizeof.
- bootcheck asserted a 31-byte file after appending to
"hello-from-schunix"; the shorter string makes it 29.
Both are the same mistake: a string literal whose length is written out
somewhere else. Full suite green -- base, Tty, Ps, Sock, Fb, Usb, Evdev.
1.8 KiB
Schcom — the SchOS Compositor
Owns the display. Every pixel that reaches the screen goes through it.
Clients do not draw to the framebuffer; they draw into their own buffers and hand them over. Schcom decides what is on top of what, composites the result, and presents it. It also owns input: it reads the raw event devices and sends each event to whichever client should have it.
That is the whole job. Window placement is not part of it — that is SchWM's, and Schcom exposes a protocol for it rather than implementing policy itself.
Status
Not started. Scoped only.
What it needs from the kernel first
| Need | State |
|---|---|
Shared memory (shmget/shmat/shmdt) |
done |
mmap of /dev/fb0 |
done |
| Framebuffer geometry via the fbdev ioctls | done |
Unix domain sockets, with SCM_RIGHTS |
missing — socket() is a NO_LINUX stub |
| Raw input events — key down/up with modifiers | missing — input only arrives cooked, through the tty line discipline |
| Mode setting and double buffering | missing — needs the virtio-gpu driver |
The two marked missing are hard blockers, not inconveniences. A client and the compositor have to pass a buffer handle between them, and a pipe cannot carry one. And a compositor that reads the tty gets line-buffered text delivered to a single foreground process, which is not input in any sense it can use.
Design notes, so far
- Buffers are shared memory, not pipes. A pipe means copying every frame; at 800×600×32 that is 1.9 MB per frame per client. shm exists for this.
- One protocol, versioned from the start. SchWM and SchDE are separate programs, so the protocol is a real compatibility surface from day one, not after the fact.
- Policy belongs to SchWM. If Schcom starts deciding where windows go, the split has already failed.