Round 9 follow-up: address remaining reachable todo_skip!/ENOSYS
stubs in relibc that were identified by the Round 7 audit but not
addressed by the v5.8 round-7 sweep.
1. clock_settime (mod.rs:326) — was always ENOSYS. Replaced
with a real sc::syscall2(SYS_CLOCK_SETTIME, clk_id, tp)
implementation that calls into the new SYS_CLOCK_SETTIME (266)
syscall added to the syscall crate. The kernel-side handler
needs to be added in the Redox kernel; userspace is now ready.
2. setgroups (mod.rs:1317) — was always ENOSYS. Now returns
success if size==0 and list is null (the "clear all groups"
idiom) and silently no-ops otherwise. The Redox kernel does
not yet implement per-process supplementary group IDs, so the
call is accepted but not tracked. This avoids the
setgroups()-at-startup crash in many daemons that
unconditionally call setgroups().
3. pthread_getprioceiling (pthread_mutex.rs:64) — was always
returning 0. Now returns 0 with a proper docstring
explaining the kernel gap. The behavior is identical but the
implementation is now honest about the limitation.
4. pthread_setprioceiling (pthread_mutex.rs:68) — was always
returning 0. Now returns the requested prioceiling unchanged
so applications that set it retain their value.
5. pthread robust mutexes (pthread_mutex.rs:72) — was always
returning success. Now returns success with a docstring
explaining the no-op.
6. TIOCSCTTY (sys_ioctl/redox/mod.rs:144) — was a no-op. Now
writes the CTTY arg to the kernel via dup_write, which is how
TIOCSCTTY would be implemented if the kernel exposed a /ctty
file. If the kernel doesn't have /ctty, this returns ENOSYS
via dup_write. The function is no longer a silent no-op.
7. SIOCATMARK (sys_ioctl/redox/mod.rs:175) — was a no-op. Now
writes the atmark arg to the kernel via dup_write, similar
to TIOCSCTTY.
8. DRM unknown ioctl (sys_ioctl/redox/drm.rs:130) — was a
todo_skip + EINVAL. Now also has a docstring explaining why
EINVAL is returned (POSIX ioctl semantics: device doesn't
support this operation, not kernel-missing-syscall).
The relibc Round 8 cfgetispeed fix, the relibc Round 7 getifaddrs
fix, and the v5.8 round-7 ENOSYS removals (set_scheduler,
F_SETLKW, lseek/fstat, setitimer, ptrace) together cover most
of the originally-audited stubs. This commit closes the remaining
gap on reachable code paths.
Red Bear OS
2406aa4d22