nix-super/src/libstore/content-address.hh
John Ericson 46e942ff9e Do big rename to clean up code
- `PathReferences` -> `References`

- `PathReferences<StorePath>` -> `StoreReference`

- `references` -> `others`

- `hasSelfReference` -> `self`

And get rid of silly subclassing
2023-01-06 15:36:05 -05:00

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#pragma once
#include <variant>
#include "hash.hh"
#include "path.hh"
#include "comparator.hh"
#include "reference-set.hh"
namespace nix {
/*
* Content addressing method
*/
/* We only have one way to hash text with references, so this is a single-value
type, mainly useful with std::variant.
*/
struct TextHashMethod : std::monostate { };
enum struct FileIngestionMethod : uint8_t {
Flat = false,
Recursive = true
};
struct FixedOutputHashMethod {
FileIngestionMethod fileIngestionMethod;
HashType hashType;
};
/* Compute the prefix to the hash algorithm which indicates how the files were
ingested. */
std::string makeFileIngestionPrefix(FileIngestionMethod m);
/* Just the type of a content address. Combine with the hash itself, and we
have a `ContentAddress` as defined below. Combine that, in turn, with info
on references, and we have `ContentAddressWithReferences`, as defined
further below. */
typedef std::variant<
TextHashMethod,
FixedOutputHashMethod
> ContentAddressMethod;
ContentAddressMethod parseContentAddressMethod(std::string_view rawCaMethod);
std::string renderContentAddressMethod(ContentAddressMethod caMethod);
/*
* Mini content address
*/
struct TextHash {
Hash hash;
GENERATE_CMP(TextHash, me->hash);
};
/// Pair of a hash, and how the file system was ingested
struct FixedOutputHash {
FileIngestionMethod method;
Hash hash;
std::string printMethodAlgo() const;
GENERATE_CMP(FixedOutputHash, me->method, me->hash);
};
/*
We've accumulated several types of content-addressed paths over the years;
fixed-output derivations support multiple hash algorithms and serialisation
methods (flat file vs NAR). Thus, ca has one of the following forms:
* text:sha256:<sha256 hash of file contents>: For paths
computed by makeTextPath() / addTextToStore().
* fixed:<r?>:<ht>:<h>: For paths computed by
makeFixedOutputPath() / addToStore().
*/
typedef std::variant<
TextHash, // for paths computed by makeTextPath() / addTextToStore
FixedOutputHash // for path computed by makeFixedOutputPath
> ContentAddress;
std::string renderContentAddress(ContentAddress ca);
std::string renderContentAddress(std::optional<ContentAddress> ca);
ContentAddress parseContentAddress(std::string_view rawCa);
std::optional<ContentAddress> parseContentAddressOpt(std::string_view rawCaOpt);
Hash getContentAddressHash(const ContentAddress & ca);
/*
* References set
*/
typedef References<StorePath> StoreReferences;
/*
* Full content address
*
* See the schema for store paths in store-api.cc
*/
// This matches the additional info that we need for makeTextPath
struct TextInfo : TextHash {
// References for the paths, self references disallowed
StorePathSet references;
GENERATE_CMP(TextInfo, *(const TextHash *)me, me->references);
};
struct FixedOutputInfo : FixedOutputHash {
// References for the paths
StoreReferences references;
GENERATE_CMP(FixedOutputInfo, *(const FixedOutputHash *)me, me->references);
};
typedef std::variant<
TextInfo,
FixedOutputInfo
> ContentAddressWithReferences;
ContentAddressWithReferences caWithoutRefs(const ContentAddress &);
struct StorePathDescriptor {
std::string name;
ContentAddressWithReferences info;
GENERATE_CMP(StorePathDescriptor, me->name, me->info);
};
}