Wrap fmt() calls in lambdas to defer string formatting until the
feature check fails. This avoids unnecessary string formatting in
the common case where the feature is enabled.
Addresses performance concern raised by xokdvium in PR review.
The refactor in the last commit fixed the bug it was supposed to fix,
but introduced a new bug in that sometimes we tried to write a resolved
derivation to a store before all its `inputSrcs` were in that store.
The solution is to defer writing the derivation until inside
`DerivationBuildingGoal`, just before we do an actual build. At this
point, we are sure that all inputs in are the store.
This does have the side effect of meaning we don't write down the
resolved derivation in the substituting case, only the building case,
but I think that is actually fine. The store that actually does the
building should make a record of what it built by storing the resolved
derivation. Other stores that just substitute from that store don't
necessary want that derivation however. They can trust the substituter
to keep the record around, or baring that, they can attempt to re
resolve everything, if they need to be audited.
(cherry picked from commit c97b050a6c)
Resolve the derivation before creating a building goal, in a context
where we know what output(s) we want. That way we have a chance just to
download the outputs we want.
Fix#13247
(cherry picked from commit 39f6fd9b46)
std::regex is a really bad tool for parsing things, since
it tends to overflow the stack pretty badly. See the build failure
under ASan in [^].
[^]: https://hydra.nixos.org/build/310077167/nixlog/5
CURL is not very strict about validation of URLs passed to it. We
should reflect this in our handling of URLs that we get from the user
in <nix/fetchurl.nix> or builtins.fetchurl. ValidURL was an attempt to
rectify this, but it turned out to be too strict. The only good way to
resolve this is to pass (in some cases) the user-provided string verbatim
to CURL. Other usages in libfetchers still benefit from using structured
ParsedURL and validation though.
nix store prefetch-file --name foo 'https://cdn.skypack.dev/big.js@^5.2.2'
error: 'https://cdn.skypack.dev/big.js@^5.2.2' is not a valid URL: leftover
The previous implementation had a check-then-create race condition where
multiple threads could simultaneously:
1. Check the cache and find no provider (line 122)
2. Create their own providers (lines 126-145)
3. Insert into cache (line 161)
This resulted in multiple credential providers being created when
downloading multiple packages in parallel, as each .narinfo download
would trigger provider creation on its own thread.
Fix by using boost::concurrent_flat_map's try_emplace_and_cvisit, which
provides atomic get-or-create semantics:
- f1 callback: Called atomically during insertion, creates the provider
- f2 callback: Called if key exists, returns cached provider
- Other threads are blocked during f1, so no nullptr is ever visible
This commit adds two key fixes to http-binary-cache-store.cc to
properly support the new curl-based S3 implementation:
1. **Consistent cache key handling**: Use `getReference().render(withParams=false)`
for disk cache keys instead of `cacheUri.to_string()`. This ensures cache
keys are consistent with the S3 implementation and don't include query
parameters, which matches the behavior expected by Store::queryPathInfo()
lookups.
2. **S3 query parameter preservation**: When generating file transfer requests
for S3 URLs, preserve query parameters from the base URL (region, endpoint,
etc.) when the relative path doesn't have its own query parameters. This
ensures S3-specific configuration is propagated to all requests.
I want to separate "policy" from "mechanism".
Now the logic to decide how to build (a policy choice, though with some
hard constraints) is all in derivation building goal, and all in the
same spot. build hook, external builder, or local builder --- the choice
between all three is made in the same spot --- pure policy.
Now, if you want to use the external deriation builder, you simply
provide the `ExternalBuilder` you wish to use, and there is no
additional checking --- pure mechanism. It is the responsibility of the
caller to choose an external builder that works for the derivation in
question.
Also, `checkSystem()` was the only thing throwing `BuildError` from
`startBuilder`. Now that that is gone, we can now remove the
`try...catch` around that.
Add a new S3BinaryCacheStore implementation that inherits from
HttpBinaryCacheStore.
The implementation is activated with NIX_WITH_CURL_S3, keeping the
existing NIX_WITH_S3_SUPPORT (AWS SDK) implementation unchanged.
This barfed with
error: [json.exception.type_error.302] type must be string, but is array
on `nix build github:malt3/bazel-env#bazel-env` because it has a `exportReferencesGraph` with a value like `["string",...["string"]]`.
Add a `UsernameAuth` struct and optional `usernameAuth` field to
`FileTransferRequest` to support programmatic username/password
authentication.
This uses curl's `CURLOPT_USERNAME`/`CURLOPT_PASSWORD` options, which
works with multiple protocols (HTTP, FTP, etc.) and is not specific to
any particular authentication scheme.
The primary motivation is to enable S3 authentication refactoring where
AWS credentials (access key ID and secret access key) can be passed
through this general-purpose mechanism, reducing the amount of
S3-specific code behind `#if NIX_WITH_CURL_S3` guards.
Firstly, this is now available on darwin where the default in llvm 19.
Secondly, this leads to very weird segfaults when building with newer nixpkgs for some reason.
(It's UB after all).
This appears when building with the following:
mesonComponentOverrides = finalAttrs: prevAttrs: {
mesonBuildType = "debugoptimized";
dontStrip = true;
doCheck = false;
separateDebugInfo = false;
preConfigure = (prevAttrs.preConfigure or "") + ''
case "$mesonBuildType" in
release|minsize|debugoptimized) appendToVar mesonFlags "-Db_lto=true" ;;
*) appendToVar mesonFlags "-Db_lto=false" ;;
esac
'';
};
And with the following nixpkgs input:
nix build ".#nix-cli" -L --override-input nixpkgs "https://releases.nixos.org/nixos/unstable/nixos-25.11pre870157.7df7ff7d8e00/nixexprs.tar.xz"
Stacktrace:
#0 0x00000000006afdc0 in ?? ()
#1 0x00007ffff71cebb6 in _Unwind_ForcedUnwind_Phase2 () from /nix/store/41ym1jm1b7j3rhglk82gwg9jml26z1km-gcc-14.3.0-lib/lib/libgcc_s.so.1
#2 0x00007ffff71cf5b5 in _Unwind_Resume () from /nix/store/41ym1jm1b7j3rhglk82gwg9jml26z1km-gcc-14.3.0-lib/lib/libgcc_s.so.1
#3 0x00007ffff7eac7d8 in std::basic_ios<char, std::char_traits<char> >::~basic_ios (this=<optimized out>, this=<optimized out>)
at /nix/store/82kmz7r96navanrc2fgckh2bamiqrgsw-gcc-14.3.0/include/c++/14.3.0/bits/basic_ios.h:286
#4 std::__cxx11::basic_ostringstream<char, std::char_traits<char>, std::allocator<char> >::basic_ostringstream (this=<optimized out>, this=<optimized out>)
at /nix/store/82kmz7r96navanrc2fgckh2bamiqrgsw-gcc-14.3.0/include/c++/14.3.0/sstream:806
#5 nix::SimpleLogger::logEI (this=<optimized out>, ei=...) at ../logging.cc:121
#6 0x00007ffff7515794 in nix::Logger::logEI (this=0x675450, lvl=nix::lvlError, ei=...) at /nix/store/bkshji3nnxmrmgwa4n2kaxadajkwvn65-nix-util-2.32.0pre-dev/include/nix/util/logging.hh:144
#7 nix::handleExceptions (programName=..., fun=...) at ../shared.cc:336
#8 0x000000000047b76b in main (argc=<optimized out>, argv=<optimized out>) at /nix/store/82kmz7r96navanrc2fgckh2bamiqrgsw-gcc-14.3.0/include/c++/14.3.0/bits/new_allocator.h:88
This broke invocations like:
NIX_SSHOPTS='-p2222 -oUserKnownHostsFile=/dev/null -oStrictHostKeyChecking=no' nix copy /nix/store/......-foo --to ssh-ng://root@localhost
In Nix 2.30.2, fakeSSH was enabled when the "thing I want to connect to"
was plain old "localhost". Previously, this check was written as:
, fakeSSH(host == "localhost")
Given the above invocation, `host` would have been `root@localhost`, and
thus `fakeSSH` would be `false` because `root@localhost` != `localhost`.
However, since 49ba06175e, `authority.host`
returned _just_ the host (`localhost`, no user) and erroneously enabled
`fakeSSH` in this case, causing `NIX_SSHOPTS` to be ignored (since,
when `fakeSSH` is `true`, `SSHMaster::startCommand` doesn't call
`addCommonSSHOpts`).
`authority.to_string()` accurately returns the expected `root@localhost`
format (given the above invocation), fixing this.
These are helper programs that execute derivations for specified
system types (e.g. using QEMU to emulate another system type).
To use, set `external-builders`:
external-builders = [{"systems": ["aarch64-linux"], "program": "/path/to/external-builder.py"}]
The external builder gets one command line argument, the path to a JSON file containing all necessary information about the derivation:
{
"args": [...],
"builder": "/nix/store/kwcyvgdg98n98hqapaz8sw92pc2s78x6-bash-5.2p37/bin/bash",
"env": {
"HOME": "/homeless-shelter",
...
},
"realStoreDir": "/tmp/nix/nix/store",
"storeDir": "/nix/store",
"tmpDir": "/tmp/nix-shell.dzQ2hE/nix-build-patchelf-0.14.3.drv-46/build",
"tmpDirInSandbox": "/build"
}
Co-authored-by: Cole Helbling <cole.helbling@determinate.systems>
Introduce a new build option 'curl-s3-store' for the curl-based S3
implementation, separate from the existing AWS SDK-based 's3-store'.
The two options are mutually exclusive to avoid conflicts.
Users can enable the new implementation with:
-Dcurl-s3-store=enabled -Ds3-store=disabled
Add lightweight AWS credential resolution using AWS CRT (Common Runtime)
instead of the full AWS SDK. This provides credential management for the
upcoming curl-based S3 implementation.
