This doesn't change behaviour on the 64bit side of things.
Currently the 32bit syscall implementation is "best effort".
Anything that easily maps is passed through, and a few minor ones that
rely on iovec are handled.
Still around 80 syscalls that aren't punched through yet.
Few of these changes could have been split up so it's a bit of a
nightmare.
Almost all of these end up being simple passthrough.
This covers most syscalls, the remaining ones are signal related, exec
related, or rseq required.
All of these syscalls exist prior to Linux 5.0. We are using these with
the expectation still that the host Linux implementation is 5.0 or
higher.
Once we implement newer syscalls we will need to start checking for host
Linux version. We don't really have a care about devices shipping older
4.x kernels atm.
This helps out Mono's garbage collector specifically. There is a minor
race that can currently occur with signal 63 but that technically should
only occur on a pause or stop condition.
Might need to change this behaviour if it becomes a problem
Since we track the PID and TID of the threads for signaling purposes, we
had the problem that if a process forked and the child then shuts down.
It was still tracking the parent thread as executing, thus it would send
it a tgkill to shut it down.
This was unintended behaviour and is now stopped
Just use the syscall directly rather than call through the glibc
interface.
The getpriority syscall biases the return value so it never returns a
negative, while the glibc interface returns [-20,19), so you need to do
some errno juggling for the -1 return.
Just use the syscall directly instead
Fixes some game complaining heavily when getpriority results were wrong
Instead of having this file mostly just copy and pasted, it'll now be
generated.
We end up losing a lot of supported flags with this change, which is for
the best since we wouldn't have actually supported those things.
This requires implementing custom ASM dispatchers for the interpreter
side of things so it works correctly.
Allows all of our CPU backends to safely support signaling.
This is a bit of a nightmare change and requires rethinking logic about
debugging in some instances.
Any time a guest signal is blocked, add it to the guest signal mask.
This doesn't use a signal queue so repeat signals can end up being lost.
This is expected behaviour
This doesn't help with implementing the problem of unblocking signals
causing the masked signal to be resent
This syscall requires the application to have root and will fail with
-EPERM otherwise.
Implementing this as just an -EPERM return allows Crispy Doom to run
It needs to track guest SigAltAction and have its own definitions for
sigaction and sa_mask. sa_mask specifically is defined differently
between the kernel and glibc.
Also fixes some issues with the SignalDelegator that posix tests found
Allows us to register host and guest signal delegators.
Currently only host signals are handled, guest signal delegation will
take a bit of work still.
This was spending ~60seconds of time compiling on my c630.
Something about fmt string formatting causing heavy compile times on
ARM.
Better to just compile it out anyway.
