Because of an objc quirk[1], calling curl_global_init for the first time
after fork() will always result in a crash.
Up until now the solution has been to set
OBJC_DISABLE_INITIALIZE_FORK_SAFETY for every nix process to ignore
that error.
This is less than ideal because we were setting it in package.nix,
which meant that running nix tests locally would fail because
that variable was not set.
Instead of working around that error we address it at the core -
by calling curl_global_init inside initLibStore, which should mean
curl will already have been initialized by the time we try to do so in
a forked process.
[1] 01edf1705f/runtime/objc-initialize.mm (L614-L636)
(cherry-picked and adapted from c7d97802e4)
Caused by 1d3696f0fb
Without this fix the kept build directory is readable only by root
```
$ sudo ls -ld /comp-temp/nix-build-openssh-static-x86_64-unknown-linux-musl-9.8p1.drv-5
drwx------ root root 60 B Wed Sep 11 00:09:48 2024 /comp-temp/nix-build-openssh-static-x86_64-unknown-linux-musl-9.8p1.drv-5/
$ sudo ls -ld /comp-temp/nix-build-openssh-static-x86_64-unknown-linux-musl-9.8p1.drv-5/build
drwxr-xr-x nixbld1 nixbld 80 B Wed Sep 11 00:09:58 2024 /comp-temp/nix-build-openssh-static-x86_64-unknown-linux-musl-9.8p1.drv-5/build/
```
When `nix fmt` is called without an argument, Nix appends the "." argument before calling the formatter. The comment in the code is:
> Format the current flake out of the box
This also happens when formatting sub-folders.
This means that the formatter is now unable to distinguish, as an interface, whether the "." argument is coming from the flake or the user's intent to format the current folder. This decision should be up to the formatter.
Treefmt, for example, will automatically look up the project's root and format all the files. This is the desired behaviour. But because the "." argument is passed, it cannot function as expected.
This fixes the warning
$ nix eval --store /tmp/nix --expr 'builtins.fetchTree { type = "git"; url = "https://github.com/DeterminateSystems/attic"; ref = "fixups-for-magic-nix-cache"; rev = "635753a2069d4b8228e846dc5c09ad361c75cd1a"; }'
warning: could not update mtime for file '/home/eelco/.cache/nix/gitv3/09788h9zgba5lbfkaa6ija2dvi004jwsqjf5ln21i2njs07cz766/refs/heads/fixups-for-magic-nix-cache': error: changing modification time of '"/home/eelco/.cache/nix/gitv3/09788h9zgba5lbfkaa6ija2dvi004jwsqjf5ln21i2njs07cz766/refs/heads/fixups-for-magic-nix-cache"': No such file or directory
When we're fetching by rev, that file doesn't necessarily exist, and we
don't care about it anyway.
Fixes
$ nix flake metadata --store /tmp/nix nixpkgs
error: path '/tmp/nix/nix/store/65xpqkz92d9j7k5ric4z8lzhiigxsfbg-source/flake.nix' is not in the Nix store
This has been broken since 598deb2b23.
On macOS, `mkdir("x/')` behaves differently than `mkdir("x")` if `x` is
a dangling symlink (the formed succeed while the latter fails). So make
sure we always strip the trailing slash.
/tmp/ecstatic-euler-mAFGV7
% /home/joerg/git/nix/build/subprojects/nix/nix repl
Nix 2.25.0
Type :? for help.
after doing rm /tmp/ecstatic-euler-mAFGV7 this will result in:
nix-repl> :lf .
error: cannot determine current working directory: No such file or directory
Before it would make the repl crash
/tmp/clever-hermann-MCm7A9
% /home/joerg/git/nix/build/subprojects/nix/nix repl
Nix 2.25.0
Type :? for help.
nix-repl> :lf .
error: filesystem error: cannot get current path: No such file or directory
Before:
nix-env % ./src/nix/nix eval --impure --expr 'let f = builtins.readDir "/nix/store/hs3yxdq9knimwdm51gvbs4dvncz46f9d-hello-2.12.1/foo"; in f' --show-trace
error: filesystem error: directory iterator cannot open directory: No such file or directory [/nix/store/hs3yxdq9knimwdm51gvbs4dvncz46f9d-hello-2.12.1/foo]
After:
error:
… while calling the 'readDir' builtin
at «string»:1:9:
1| let f = builtins.readDir "/nix/store/hs3yxdq9knimwdm51gvbs4dvncz46f9d-hello-2.12.1/foo"; in f
| ^
error: reading directory '/nix/store/hs3yxdq9knimwdm51gvbs4dvncz46f9d-hello-2.12.1/foo': No such file or directory
this should make it more obvious how things are related to each other, and also
hopefully expose the historical context without having to say on every
corner that these details are accounting for legacy decisions.
The daemon process is now moved into a new sub-cgroup called nix-daemon when the
daemon starts. This is necessary to abide by the no-processes-in-inner-nodes
rule, because the service cgroup becomes an inner node when the child cgroups
for the build are created (see LocalDerivationGoal::startBuilder()).
See #9675
This broke in #11005. Any number of PathSubstitutionGoals would
be woken up by a single build slot becoming available. If there
are a lot of substitution goals active, this could lead to us
running out of file descriptors (especially on macOS where the
default limit is 256).
libgit2 didn't write thin ones, hence the patch.
This should improve performance on systems with weak I/O in ~/.cache,
especially in terms of operations per second, or where system calls
are slower. (macOS, VMs?)
Meson-ify a few things, scripts, completions, etc. Should make our Meson
build complete except for docs.
Co-Authored-By: Qyriad <qyriad@qyriad.me>
Co-Authored-By: eldritch horrors <pennae@lix.systems>
We're not replacing `Path` in exposed definitions in many cases, but
just adding alternatives. This will allow us to "top down" change `Path`
to `std::fileysystem::path`, and then we can remove the `Path`-using
utilities which will become unused.
Also add some test files which we forgot to include in the libutil unit
tests `meson.build`.
Co-Authored-By: siddhantCodes <siddhantk232@gmail.com>
This reverts commit 43e82c9446, reversing
changes made to d79b9bdec0.
Since /proc/homeless-shelter returns a different errno than /homeless-shelter (ENOENT vs EACCES), we need to revert this change.
Software depends on this error code i.e. cargo and therefore breaks.
this is only used to close non-stdio files in derivation sandboxes. we
may as well encode that in its name, drop the unnecessary integer set,
and use close_range to deal with the actual closing of files. not only
is this clearer, it also makes sandbox setup on linux fast by 1ms each
(cherry-picked and adapted from
c7d97802e4)
Co-authored-by: Eelco Dolstra <edolstra@gmail.com>
Co-authored-by: Cole Helbling <cole.e.helbling@outlook.com>
Co-authored-by: John Ericson <git@JohnEricson.me>
Since withFramedSink() is now used a lot more than in the past (for
every addToStore() variant), we were creating a lot of threads, e.g.
nix flake show --no-eval-cache --all-systems github:NixOS/nix/afdd12be5e19c0001ff3297dea544301108d298
would create 46418 threads. While threads on Linux are cheap, this is
still substantial overhead.
So instead, just poll from FramedSink before every write whether there
are pending messages from the daemon. This could slightly increase the
latency on log messages from the daemon, but not on exceptions (which
were only synchronously checked from FramedSink anyway).
This speeds up the command above from 19.2s to 17.5s on my machine (a
9% speedup).
