nix-super/src/libstore/nar-accessor.hh
2023-11-08 17:29:55 +01:00

40 lines
935 B
C++

#pragma once
///@file
#include "source-accessor.hh"
#include <functional>
#include <nlohmann/json_fwd.hpp>
namespace nix {
struct Source;
/**
* Return an object that provides access to the contents of a NAR
* file.
*/
ref<SourceAccessor> makeNarAccessor(std::string && nar);
ref<SourceAccessor> makeNarAccessor(Source & source);
/**
* Create a NAR accessor from a NAR listing (in the format produced by
* listNar()). The callback getNarBytes(offset, length) is used by the
* readFile() method of the accessor to get the contents of files
* inside the NAR.
*/
using GetNarBytes = std::function<std::string(uint64_t, uint64_t)>;
ref<SourceAccessor> makeLazyNarAccessor(
const std::string & listing,
GetNarBytes getNarBytes);
/**
* Write a JSON representation of the contents of a NAR (except file
* contents).
*/
nlohmann::json listNar(ref<SourceAccessor> accessor, const CanonPath & path, bool recurse);
}