lix/src/libstore/realisation.hh
John Ericson 2f5d3da806 Introduce OutputName and OutputNameView type aliases
Hopefully they make the code easier to understand!
2023-08-25 09:55:07 -04:00

158 lines
4.1 KiB
C++

#pragma once
///@file
#include <variant>
#include "hash.hh"
#include "path.hh"
#include "derived-path.hh"
#include <nlohmann/json_fwd.hpp>
#include "comparator.hh"
#include "crypto.hh"
namespace nix {
class Store;
struct OutputsSpec;
/**
* A general `Realisation` key.
*
* This is similar to a `DerivedPath::Opaque`, but the derivation is
* identified by its "hash modulo" instead of by its store path.
*/
struct DrvOutput {
/**
* The hash modulo of the derivation.
*
* Computed from the derivation itself for most types of
* derivations, but computed from the (fixed) content address of the
* output for fixed-output derivations.
*/
Hash drvHash;
/**
* The name of the output.
*/
OutputName outputName;
std::string to_string() const;
std::string strHash() const
{ return drvHash.to_string(Base16, true); }
static DrvOutput parse(const std::string &);
GENERATE_CMP(DrvOutput, me->drvHash, me->outputName);
};
struct Realisation {
DrvOutput id;
StorePath outPath;
StringSet signatures;
/**
* The realisations that are required for the current one to be valid.
*
* When importing this realisation, the store will first check that all its
* dependencies exist, and map to the correct output path
*/
std::map<DrvOutput, StorePath> dependentRealisations;
nlohmann::json toJSON() const;
static Realisation fromJSON(const nlohmann::json& json, const std::string& whence);
std::string fingerprint() const;
void sign(const SecretKey &);
bool checkSignature(const PublicKeys & publicKeys, const std::string & sig) const;
size_t checkSignatures(const PublicKeys & publicKeys) const;
static std::set<Realisation> closure(Store &, const std::set<Realisation> &);
static void closure(Store &, const std::set<Realisation> &, std::set<Realisation> & res);
bool isCompatibleWith(const Realisation & other) const;
StorePath getPath() const { return outPath; }
GENERATE_CMP(Realisation, me->id, me->outPath);
};
/**
* Collection type for a single derivation's outputs' `Realisation`s.
*
* Since these are the outputs of a single derivation, we know the
* output names are unique so we can use them as the map key.
*/
typedef std::map<OutputName, Realisation> SingleDrvOutputs;
/**
* Collection type for multiple derivations' outputs' `Realisation`s.
*
* `DrvOutput` is used because in general the derivations are not all
* the same, so we need to identify firstly which derivation, and
* secondly which output of that derivation.
*/
typedef std::map<DrvOutput, Realisation> DrvOutputs;
/**
* Filter a SingleDrvOutputs to include only specific output names
*
* Moves the `outputs` input.
*/
SingleDrvOutputs filterDrvOutputs(const OutputsSpec&, SingleDrvOutputs&&);
struct OpaquePath {
StorePath path;
StorePath getPath() const { return path; }
GENERATE_CMP(OpaquePath, me->path);
};
/**
* A store path with all the history of how it went into the store
*/
struct RealisedPath {
/*
* A path is either the result of the realisation of a derivation or
* an opaque blob that has been directly added to the store
*/
using Raw = std::variant<Realisation, OpaquePath>;
Raw raw;
using Set = std::set<RealisedPath>;
RealisedPath(StorePath path) : raw(OpaquePath{path}) {}
RealisedPath(Realisation r) : raw(r) {}
/**
* Get the raw store path associated to this
*/
StorePath path() const;
void closure(Store& store, Set& ret) const;
static void closure(Store& store, const Set& startPaths, Set& ret);
Set closure(Store& store) const;
GENERATE_CMP(RealisedPath, me->raw);
};
class MissingRealisation : public Error
{
public:
MissingRealisation(DrvOutput & outputId)
: MissingRealisation(outputId.outputName, outputId.strHash())
{}
MissingRealisation(std::string_view drv, OutputName outputName)
: Error( "cannot operate on output '%s' of the "
"unbuilt derivation '%s'",
outputName,
drv)
{}
};
}