See https://github.com/NixOS/nix/pull/8699#discussion_r1554312181
Casting a function pointer to `void*` is undefined behavior in the C
spec, since there are platforms with different sizes for these two kinds
of pointers. A safe alternative might be `void (*callback)()`
* add intermediate variables and clarifying comments
Co-authored-by: Alexander Groleau <alex@proof.construction>
Co-authored-by: Robert Hensing <roberth@users.noreply.github.com>
https://github.com/NixOS/nix/pull/10456 fixed the addition of symlink
store paths to the sandbox, but also made it so that the hardcoded
sandbox paths (like `/etc/hosts`) were now bind-mounted without
following the possible symlinks. This made these files unreadable if
there were symlinks (because the sandbox would now contain a symlink to
an unreachable file rather than the underlying file).
In particular, this broke FOD derivations on NixOS as `/etc/hosts` is a
symlink there.
Fix that by canonicalizing all these hardcoded sandbox paths before
adding them to the sandbox.
Like always declining; local builds only, as can be inferred from the
docs. (Not worth spending too many words on this pretty obvious
behavior, I think. Also, plans to remove it? https://github.com/NixOS/nix/issues/1221)
This requires moving resolveSymlinks() into SourceAccessor. Also, it
requires LocalStoreAccessor::maybeLstat() to work on parents of the
store (to avoid an error like "/nix is not in the store").
Fixes#10375.
Instead of relying on setup script to set output variables when
structured attributes are enabled, iterate over the values of an
outputs associative array.
See also
374fa3532e/pkgs/stdenv/generic/setup.sh (L23-L26)
Bind-mounting symlinks is apparently not possible, which is why the
thing was failing.
Fortunately, symlinks are small, so we can fallback to copy them at no cost.
Fix https://github.com/NixOS/nix/issues/9579
Co-authored-by: Artturin <Artturin@artturin.com>
Now that we have a few things identifying content address methods by
name, we should be consistent about it.
Move up the `parseHashAlgoOpt` for tidiness too.
Discussed this change for consistency's sake as part of #8876
Co-authored-by: Eelco Dolstra <edolstra@gmail.com>
This requires `--substitute-on-destination` if you want the remote side
to substitute instead of copying if possible.
For completeness sake, document it here.
Also, the stable Nix from nixpkgs is still 2.18, so more folks may
stumble upon this when this is bumped, so I'd expect this to be actually
useful.
Closes#10182
This was used in only one place, namely builtins.fetchurl with an
expected hash. Since this can cause similar issues as described
in #9814 and #9905 with the "locked" flag for fetchTarball and fetchTree,
let's just remove it.
Note that if an expected hash is given and the hash algorithm is
SHA-256, then we will never do a download anyway if the resulting
store path already exists. So removing the "locked" flag will only
cause potentially unnecessary HTTP requests (subject to the tarball
TTL) for non-SHA-256 hashes.
