blob: 634a51c389cb7942072421d156c8348b6ff58f3c (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
|
#pragma once
#include <variant>
#include "hash.hh"
namespace nix {
/**
* An enumeration of the ways we can serialize file system objects.
*/
enum struct FileIngestionMethod : uint8_t {
/**
* Flat-file hashing. Directly ingest the contents of a single file
*/
Flat = false,
/**
* Recursive (or NAR) hashing. Serializes the file-system object in Nix
* Archive format and ingest that
*/
Recursive = true
};
/**
* Somewhat obscure, used by \ref Derivation derivations and
* `builtins.toFile` currently.
*/
struct TextHash {
/**
* Hash of the contents of the text/file.
*/
Hash hash;
};
/**
* For path computed by makeFixedOutputPath.
*/
struct FixedOutputHash {
/**
* How the file system objects are serialized
*/
FileIngestionMethod method;
/**
* Hash of that serialization
*/
Hash hash;
std::string printMethodAlgo() const;
};
/**
* 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 Store::makeTextPath() / Store::addTextToStore().
*
* - ‘fixed:<r?>:<ht>:<h>’: For paths computed by
* Store::makeFixedOutputPath() / Store::addToStore().
*/
typedef std::variant<
TextHash,
FixedOutputHash
> ContentAddress;
/**
* Compute the prefix to the hash algorithm which indicates how the
* files were ingested.
*/
std::string makeFileIngestionPrefix(const FileIngestionMethod m);
/**
* Compute the content-addressability assertion (ValidPathInfo::ca) for
* paths created by Store::makeFixedOutputPath() / Store::addToStore().
*/
std::string makeFixedOutputCA(FileIngestionMethod method, const Hash & hash);
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);
/*
We only have one way to hash text with references, so this is single-value
type is only useful in std::variant.
*/
struct TextHashMethod { };
struct FixedOutputHashMethod {
FileIngestionMethod fileIngestionMethod;
HashType hashType;
};
/**
* Ways of content addressing but not a complete ContentAddress.
*
* A ContentAddress without a Hash.
*/
typedef std::variant<
TextHashMethod,
FixedOutputHashMethod
> ContentAddressMethod;
ContentAddressMethod parseContentAddressMethod(std::string_view rawCaMethod);
std::string renderContentAddressMethod(ContentAddressMethod caMethod);
}
|
