Daemon client handler processes are forked off of the main nix process
and thus will not have a signal handler thread anymore. This leads to a
high likelihood of bustage, since the Worker infrastructure expects the
interrupt infrastructure to actually, you know, work, to be able to get
interrupted.
The expected behaviour after fork is either:
- Start a signal handler thread if you expect to do complicated things
that need ReceiveInterrupts.
- Call restoreProcessContext and don't handle signals specially
otherwise.
Change-Id: I73d36b5bbf96dddd21d5e1c3bd0484d715c00e8b
The build hook is still running locally, so it will run with the same default
settings. Hence, just as with the daemon, it is enough to send it only the
overridden settings. This will prevent warnings like
warning: Ignoring setting 'auto-allocate-uids' because experimental feature 'auto-allocate-uids' is not enabled
when the user didn't actually set those settings.
This is inspired by and an alternative to [0].
[0] https://github.com/NixOS/nix/pull/10049
Change-Id: I77ea62cd017614b16b55979dd30e75f09f860d21
This splits `ignoreException` into `ignoreExceptionExceptInterrupt`
(which ignores all exceptions except `Interrupt`, which indicates a
SIGINT/CTRL-C) and `ignoreExceptionInDestructor` (which ignores all
exceptions, so that destructors do not throw exceptions).
This prevents many cases where Nix ignores CTRL-C entirely.
See: https://github.com/NixOS/nix/issues/7245
Upstream-PR: https://github.com/NixOS/nix/pull/11618
Change-Id: Ie7d2467eedbe840d1b9fa2e88a4e88e4ab26a87b
don't keep fds open we're not using. currently this does not cause any
problems, but it does increase the size of our fd table needlessly and
in the future, when we have proper async processing, having builderOut
open in the daemon once the hook has been fully started is problematic
Change-Id: I6e7fb773b280b042873103638d3e04272ca1e4fc
copy-constructing or assigning from pid_t can easily lead to duplicate
Pid instances for the same process if a pid_t was used carelessly, and
Pid itself was copy-constructible. both could cause surprising results
such as killing processes twice (which could become very problemantic,
but luckily modern systems don't reuse PIDs all that quickly), or more
than one piece of the code believing it owns a process when neither do
Change-Id: Ifea7445f84200b34c1a1d0acc2cdffe0f01e20c6
add a reset() method to close the wrapped fd instead of assigning magic
constants. also make the from-fd constructor explicit so you can't
accidentally assign the *wrong* magic constant, or even an unrelated
integer that also just happens to be an fd by pure chance.
Change-Id: I51311b0f6e040240886b5103d39d1794a6acc325
Rather than doing `allowEmpty` as boolean, have separate types and use
`std::optional`. This makes it harder to forget the possibility of an
empty path.
The `build-hook` setting was categorized as a `PathSetting`, but
actually it was split into arguments. No good! Now, it is
`Setting<Strings>` which actually reflects what it means and how it is
used.
Because of the subtyping, we now also have support for
`Setting<std::optional<String>>` in general. I imagine this can be used
to clean up many more settings also.
Call it as `['nix', '__build-remote', ... ]` rather than the previous
`["__build-remote", "nix __build-remote", ... ]` which seemed to have
been most likely unintended
