249 lines
8.5 KiB
C++
249 lines
8.5 KiB
C++
#pragma once
|
|
|
|
#include "path.hh"
|
|
#include "types.hh"
|
|
#include "hash.hh"
|
|
#include "content-address.hh"
|
|
#include "sync.hh"
|
|
|
|
#include <map>
|
|
#include <variant>
|
|
|
|
|
|
namespace nix {
|
|
|
|
|
|
/* Abstract syntax of derivations. */
|
|
|
|
/* The traditional non-fixed-output derivation type. */
|
|
struct DerivationOutputInputAddressed
|
|
{
|
|
StorePath path;
|
|
};
|
|
|
|
/* Fixed-output derivations, whose output paths are content addressed
|
|
according to that fixed output. */
|
|
struct DerivationOutputCAFixed
|
|
{
|
|
FixedOutputHash hash; /* hash used for expected hash computation */
|
|
StorePath path(const Store & store, std::string_view drvName, std::string_view outputName) const;
|
|
};
|
|
|
|
/* Floating-output derivations, whose output paths are content addressed, but
|
|
not fixed, and so are dynamically calculated from whatever the output ends
|
|
up being. */
|
|
struct DerivationOutputCAFloating
|
|
{
|
|
/* information used for expected hash computation */
|
|
FileIngestionMethod method;
|
|
HashType hashType;
|
|
};
|
|
|
|
/* Input-addressed output which depends on a (CA) derivation whose hash isn't
|
|
* known atm
|
|
*/
|
|
struct DerivationOutputDeferred {};
|
|
|
|
struct DerivationOutput
|
|
{
|
|
std::variant<
|
|
DerivationOutputInputAddressed,
|
|
DerivationOutputCAFixed,
|
|
DerivationOutputCAFloating,
|
|
DerivationOutputDeferred
|
|
> output;
|
|
|
|
/* Note, when you use this function you should make sure that you're passing
|
|
the right derivation name. When in doubt, you should use the safer
|
|
interface provided by BasicDerivation::outputsAndOptPaths */
|
|
std::optional<StorePath> path(const Store & store, std::string_view drvName, std::string_view outputName) const;
|
|
};
|
|
|
|
typedef std::map<std::string, DerivationOutput> DerivationOutputs;
|
|
|
|
/* These are analogues to the previous DerivationOutputs data type, but they
|
|
also contains, for each output, the (optional) store path in which it would
|
|
be written. To calculate values of these types, see the corresponding
|
|
functions in BasicDerivation */
|
|
typedef std::map<std::string, std::pair<DerivationOutput, std::optional<StorePath>>>
|
|
DerivationOutputsAndOptPaths;
|
|
|
|
/* For inputs that are sub-derivations, we specify exactly which
|
|
output IDs we are interested in. */
|
|
typedef std::map<StorePath, StringSet> DerivationInputs;
|
|
|
|
enum struct DerivationType : uint8_t {
|
|
InputAddressed,
|
|
DeferredInputAddressed,
|
|
CAFixed,
|
|
CAFloating,
|
|
};
|
|
|
|
/* Do the outputs of the derivation have paths calculated from their content,
|
|
or from the derivation itself? */
|
|
bool derivationIsCA(DerivationType);
|
|
|
|
/* Is the content of the outputs fixed a-priori via a hash? Never true for
|
|
non-CA derivations. */
|
|
bool derivationIsFixed(DerivationType);
|
|
|
|
/* Is the derivation impure and needs to access non-deterministic resources, or
|
|
pure and can be sandboxed? Note that whether or not we actually sandbox the
|
|
derivation is controlled separately. Never true for non-CA derivations. */
|
|
bool derivationIsImpure(DerivationType);
|
|
|
|
/* Does the derivation knows its own output paths?
|
|
* Only true when there's no floating-ca derivation involved in the closure.
|
|
*/
|
|
bool derivationHasKnownOutputPaths(DerivationType);
|
|
|
|
struct BasicDerivation
|
|
{
|
|
DerivationOutputs outputs; /* keyed on symbolic IDs */
|
|
StorePathSet inputSrcs; /* inputs that are sources */
|
|
std::string platform;
|
|
Path builder;
|
|
Strings args;
|
|
StringPairs env;
|
|
std::string name;
|
|
|
|
BasicDerivation() = default;
|
|
virtual ~BasicDerivation() { };
|
|
|
|
bool isBuiltin() const;
|
|
|
|
/* Return true iff this is a fixed-output derivation. */
|
|
DerivationType type() const;
|
|
|
|
/* Return the output names of a derivation. */
|
|
StringSet outputNames() const;
|
|
|
|
/* Calculates the maps that contains all the DerivationOutputs, but
|
|
augmented with knowledge of the Store paths they would be written
|
|
into. */
|
|
DerivationOutputsAndOptPaths outputsAndOptPaths(const Store & store) const;
|
|
|
|
static std::string_view nameFromPath(const StorePath & storePath);
|
|
};
|
|
|
|
struct Derivation : BasicDerivation
|
|
{
|
|
DerivationInputs inputDrvs; /* inputs that are sub-derivations */
|
|
|
|
/* Print a derivation. */
|
|
std::string unparse(const Store & store, bool maskOutputs,
|
|
std::map<std::string, StringSet> * actualInputs = nullptr) const;
|
|
|
|
/* Return the underlying basic derivation but with these changes:
|
|
|
|
1. Input drvs are emptied, but the outputs of them that were used are
|
|
added directly to input sources.
|
|
|
|
2. Input placeholders are replaced with realized input store paths. */
|
|
std::optional<BasicDerivation> tryResolve(Store & store);
|
|
|
|
Derivation() = default;
|
|
Derivation(const BasicDerivation & bd) : BasicDerivation(bd) { }
|
|
Derivation(BasicDerivation && bd) : BasicDerivation(std::move(bd)) { }
|
|
};
|
|
|
|
|
|
class Store;
|
|
|
|
enum RepairFlag : bool { NoRepair = false, Repair = true };
|
|
|
|
/* Write a derivation to the Nix store, and return its path. */
|
|
StorePath writeDerivation(Store & store,
|
|
const Derivation & drv,
|
|
RepairFlag repair = NoRepair,
|
|
bool readOnly = false);
|
|
|
|
/* Read a derivation from a file. */
|
|
Derivation parseDerivation(const Store & store, std::string && s, std::string_view name);
|
|
|
|
// FIXME: remove
|
|
bool isDerivation(const std::string & fileName);
|
|
|
|
/* Calculate the name that will be used for the store path for this
|
|
output.
|
|
|
|
This is usually <drv-name>-<output-name>, but is just <drv-name> when
|
|
the output name is "out". */
|
|
std::string outputPathName(std::string_view drvName, std::string_view outputName);
|
|
|
|
// known CA drv's output hashes, current just for fixed-output derivations
|
|
// whose output hashes are always known since they are fixed up-front.
|
|
typedef std::map<std::string, Hash> CaOutputHashes;
|
|
|
|
struct DeferredHash { Hash hash; };
|
|
|
|
typedef std::variant<
|
|
Hash, // regular DRV normalized hash
|
|
CaOutputHashes, // Fixed-output derivation hashes
|
|
DeferredHash // Deferred hashes for floating outputs drvs and their dependencies
|
|
> DrvHashModulo;
|
|
|
|
/* Returns hashes with the details of fixed-output subderivations
|
|
expunged.
|
|
|
|
A fixed-output derivation is a derivation whose outputs have a
|
|
specified content hash and hash algorithm. (Currently they must have
|
|
exactly one output (`out'), which is specified using the `outputHash'
|
|
and `outputHashAlgo' attributes, but the algorithm doesn't assume
|
|
this.) We don't want changes to such derivations to propagate upwards
|
|
through the dependency graph, changing output paths everywhere.
|
|
|
|
For instance, if we change the url in a call to the `fetchurl'
|
|
function, we do not want to rebuild everything depending on it---after
|
|
all, (the hash of) the file being downloaded is unchanged. So the
|
|
*output paths* should not change. On the other hand, the *derivation
|
|
paths* should change to reflect the new dependency graph.
|
|
|
|
For fixed-output derivations, this returns a map from the name of
|
|
each output to its hash, unique up to the output's contents.
|
|
|
|
For regular derivations, it returns a single hash of the derivation
|
|
ATerm, after subderivations have been likewise expunged from that
|
|
derivation.
|
|
*/
|
|
DrvHashModulo hashDerivationModulo(Store & store, const Derivation & drv, bool maskOutputs);
|
|
|
|
/*
|
|
Return a map associating each output to a hash that uniquely identifies its
|
|
derivation (modulo the self-references).
|
|
*/
|
|
std::map<std::string, Hash> staticOutputHashes(Store& store, const Derivation& drv);
|
|
|
|
/* Memoisation of hashDerivationModulo(). */
|
|
typedef std::map<StorePath, DrvHashModulo> DrvHashes;
|
|
|
|
// FIXME: global, though at least thread-safe.
|
|
extern Sync<DrvHashes> drvHashes;
|
|
|
|
bool wantOutput(const std::string & output, const std::set<std::string> & wanted);
|
|
|
|
struct Source;
|
|
struct Sink;
|
|
|
|
Source & readDerivation(Source & in, const Store & store, BasicDerivation & drv, std::string_view name);
|
|
void writeDerivation(Sink & out, const Store & store, const BasicDerivation & drv);
|
|
|
|
/* This creates an opaque and almost certainly unique string
|
|
deterministically from the output name.
|
|
|
|
It is used as a placeholder to allow derivations to refer to their
|
|
own outputs without needing to use the hash of a derivation in
|
|
itself, making the hash near-impossible to calculate. */
|
|
std::string hashPlaceholder(const std::string_view outputName);
|
|
|
|
/* This creates an opaque and almost certainly unique string
|
|
deterministically from a derivation path and output name.
|
|
|
|
It is used as a placeholder to allow derivations to refer to
|
|
content-addressed paths whose content --- and thus the path
|
|
themselves --- isn't yet known. This occurs when a derivation has a
|
|
dependency which is a CA derivation. */
|
|
std::string downstreamPlaceholder(const Store & store, const StorePath & drvPath, std::string_view outputName);
|
|
|
|
}
|