feat: CA derivations bindings (realisation + drv accessors)#2
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domenkozar wants to merge 3 commits into
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feat: CA derivations bindings (realisation + drv accessors)#2domenkozar wants to merge 3 commits into
domenkozar wants to merge 3 commits into
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Bumps the nix flake input to cachix/nix#cachix, which combines the
existing path-info-json work with the new realisation and structured
derivation accessor C API additions.
C API additions surfaced:
- nix_api_store/fwd.h -> Generated.Nix.Store.Fwd
(canonical Store opaque type)
- nix_api_store/realisation.h -> Generated.Nix.Store.Realisation
(query_realisation + accessors)
- nix_api_store/derivation.h regenerated with
get_outputs / get_input_drv_outputs /
has_dynamic_inputs
The bindgen generator now processes fwd.h first so every store-related
header references one canonical Store type instead of each module
declaring its own.
High-level wrappers (nix-bindings):
- Nix.C.Store.Derivation: derivationOutputs,
derivationInputDrvOutputs, derivationHasDynamicInputs
- Nix.C.Store.Realisation: queryRealisation, realisationOutPath,
realisationSignatures
- Nix.C.Unsafe.Store: drvFromStorePath
- Nix.C.Internal: Derivation/Realisation handle types
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
The cachix client serializes nar hashes and store-path hashes in Nix's <algo>:<nix32> format, which an earlier nix-bindings revision exposed via Nix.C.Hash / Nix.C.Hash.Nix32. The current Hash type lives on Nix.C.Store.PathInfo and only had hashToSRI, so add the nix32 encoder back as Nix.C.Hash.Nix32 and a hashToNix32 method alongside hashToSRI. Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
2 tasks
Store previously carried one shared nix_c_context whose error state every operation mutated, so concurrent use (e.g. cachix push at the default 8 jobs) raced on it, corrupting error reporting and risking heap corruption. Each operation now allocates its own short lived context via withContext', matching what storePathHash already did, so a Store is safe to use from multiple threads (the underlying Nix store is itself concurrency safe). As a side effect the queryRealisation NULL vs error disambiguation now reads a private context. StorePath Eq and Ord compared the ForeignPtr address, so two handles to the same path (e.g. cloned during a closure walk) never compared equal and Set/Map StorePath failed to deduplicate. They now compare the store path hash part, restoring the value semantics the previous C++ bindings had. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Summary
Adds Haskell bindings for the new C API surface introduced on
cachix/nix#cachix(path-info-json + realisation + structured derivation accessors), so that cachix can push CA-derivation realisations through the C FFI instead ofHercules.CNix.Store.Generated.Nix.Store.Fwd(forward-declaresStoreonce so all sibling headers reference one canonical type)Generated.Nix.Store.Realisation—nix_store_query_realisation,nix_realisation_free,nix_realisation_get_out_path,nix_realisation_get_signaturesGenerated.Nix.Store.Derivationregenerated withnix_derivation_get_outputs,nix_derivation_get_input_drv_outputs,nix_derivation_has_dynamic_inputsNix.C.Store.Derivation(derivationOutputs, derivationInputDrvOutputs, derivationHasDynamicInputs) andNix.C.Store.Realisation(queryRealisation, realisationOutPath, realisationSignatures)drvFromStorePathadded toNix.C.Unsafe.StoreNix.C.Hash.Nix32+hashToNix32restored on the canonicalHashfromNix.C.Store.PathInfo(needed by cachix to render nar/store-path hashes)Bumps the
nixflake input tocachix/nix#cachix.Test plan
nix build .#nix-bindings(test suite passes)checks.x86_64-linux.ca-derivations-latest) passes — exercises the realisation push path through these bindings🤖 Generated with Claude Code