Always enables FEXServer log thread when built for Steam so that clients
can be controlled with `STEAM_FEX_LOG=1`. FEX logs will then always go
to FEXServer and those can get directed to wherever pressure-vessel
chooses.
Still creates a copy of FEXInterpreter from FEX for downstream projects
to have some time to get off the old name. Creating a symlink is kind of
a pain in cmake so just doing an install copy is easy.
This is entirely unused as FEXServer only ever reads the environment and
other configs.
There was /technically/ a weird conflict with FEXServer arguments but
that was an accident if it ever happened.
This is now relative to the time of the first message. Furthermore, display
precision is limited to milliseconds (which are actually zero-padded now!).
Newer fuse releases changed how they are waiting on child processes to
exit. Setting the signal action to SIG_IGN would cause
erofsfuse/squashfuse to inherit the ignored action and cause their
internal `wait4` syscalls to fail with ECHLD.
Set the action back to default inside the FEXServer because our original
reasoning for setting the ignoring is no longer valid. FEXInterpreter
still ignores SIGCHLD while launching FEXServer.
Maybe fixes the muvm thing people have been complaining about.
Also fixes accidental comma delimiter usage.
The problem here is that the pipe we used for telling FEXInterpreter
that the FEXServer is ready to accept connections was inherited by
erofsfuse or squashfuse. So the closing of the pipe from the FEXServer
side would leave a reference open in squashfuse or erofsfuse.
Fix this by setting FD_CLOEXEC on the pipe, but also pass the pipe FD
through an argument instead of scanning for all pipes.
Then once we execve the squashfuse/erofsfuse application, the FD isn't
inherited.
Fixes#4329
This was causing FEXServer to look in to global installed paths and
local paths for things when FEXServer was started.
Ensure it listens to FEX_PORTABLE so this doesn't occur.
This also requires us to scan both data directories and config
directories to find them.
Abstract sockets have one limitation: they are bound to a network
namespace. Chromium/CEF sandboxes using a new netns, which breaks
connecting to the FEXServer.
To work around this, use and try *both* abstract and named sockets. As
long as either the filesystem or the network is unsandboxed, things will
work. If both are sandboxed, there isn't much we can do... but at that
point we shouldn't be reinitializing the FEXServer connection anyway
since the FS should be available on FEXInterpreter startup.
Removes a global initializer and atexit registration
Ownership of this data has always been the frontend and the config
system, we just used these static vectors as a side-channel.
This was a bit confusing to read and I had always expected to change
this at some point.
Previous:
```
[INFO][1579518391560577][1601857.1601857] clone: Unsupported flags w/o CLONE_THREAD (Shared Resources), 4100
```
Now:
```
[INFO][1590468.992593376][1629501.1629501] clone: Unsupported flags w/o CLONE_THREAD (Shared Resources), 4100
```
It looks like `SYSTEMD_EXEC_PID` can leak through to the executable
environment in regular situations. Instead let's key off of
`INVOCATATION_ID` which doesn't leak through.
Fixes an edge case behaviour where FEXServer wouldn't daemonize in some
systemd environments.
Fixes#2136
This is a fairly tricky edge case to support with FEX.
If execveat is used with AT_EMPTY_PATH then the application can pass an
FD to execve instead of a filename. This includes FDs that have been
deleted from the disk so the child process can't open it by filename
anymore.
To work around this limitation, we need to pass the FD to the new FEX
process and open it directly, similar to how binfmt_misc works with FDs.
The FD will get passed through environment variables, which the new
process will check for and then remove the variable from the
environment.
Lots of prickly edge cases to support here.
Without binfmt_misc:
- Passes the FD to FEXLoader directly.
- Requires duplicating the FD if it has O_CLOEXEC on the FD.
With binfmt_misc:
- Shebang file, pass directly to FEXLoader, just like without binfmt.
- x86 ELF Files, rely on the kernel's binfmt_misc support here.
- Unsupported ELF files, let kernel handle it through binfmt_misc
Argument handling:
- The application can pass in no arguments.
- Means our application configurations were failing to find a config
- Also various checks in the frontend were failing.
- If opened through an FD, find the symlink for that FD for the
application configuration instead.
Side note:
Fixed a performance issue in execve where when we were checking for file
format support. Either ELF or Shebang files, we were reading the /whole/
file upfront. We only need to read a header worth of ELF files, and only
257 bytes if it is potentially a shebang file. Should dramatically
reduce some application's execve times.
It can be useful to know in tooling when the current active FEXServer
has exited.
Two things can happen when this command is run.
No FEXServer is active, returns immediately.
A FEXServer is active, we query for a pidfd from the active server, then
we wait until it exits.
Both instances of this is valid to use.
This is a relatively invasive change since multiple things needed to
happen at once.
* Socket based logging is removed
* Logging has been replaced to only support stdout, stderr, and server
* Server is now default and replaces what FEXLogServer did
* Server logging now uses a pipe instead of a socket
* Can be faster than stderr and stdout since the application doesn't
need to wait on terminal output
* FEXMountDaemon has been removed
* Functionality has been merged in to FEXServer
* FEXServer is always executed on FEX initialization time
* Similar in behaviour to Wine's wineserver
* Can explicitly start this before using FEX for logging purposes
* Stays around until all instances of FEX exit
* Will stick around for a short amount of time in case of spurious
execution
* FEXServer will soon be extended to do more than logging and squashfs
mounting
* FEX rootfs scripts will need to be updated to support this path
* Just means rbinding the /tmp folder and forcing a FEXServer instance
to be alive
* Pressure-vessel works fine in this case since FEXServer will already
be running
* It already rbinds the host /tmp folder which is why this works
Pepper Gray