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
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
|
#pragma once
#include <variant>
#include "hash.hh"
#include "path.hh"
namespace nix {
/*
* Mini content address
*/
enum struct FileIngestionMethod : uint8_t {
Flat = false,
Recursive = true
};
struct TextHash {
Hash hash;
};
/// Pair of a hash, and how the file system was ingested
struct FixedOutputHash {
FileIngestionMethod method;
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 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;
/* Compute the prefix to the hash algorithm which indicates how the files were
ingested. */
std::string makeFileIngestionPrefix(const FileIngestionMethod m);
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;
};
typedef std::variant<
TextHashMethod,
FixedOutputHashMethod
> ContentAddressMethod;
ContentAddressMethod parseContentAddressMethod(std::string_view rawCaMethod);
std::string renderContentAddressMethod(ContentAddressMethod caMethod);
/*
* References set
*/
template<typename Ref>
struct PathReferences
{
std::set<Ref> references;
bool hasSelfReference = false;
bool operator == (const PathReferences<Ref> & other) const
{
return references == other.references
&& hasSelfReference == other.hasSelfReference;
}
/* Functions to view references + hasSelfReference as one set, mainly for
compatibility's sake. */
StorePathSet referencesPossiblyToSelf(const Ref & self) const;
void insertReferencePossiblyToSelf(const Ref & self, Ref && ref);
void setReferencesPossiblyToSelf(const Ref & self, std::set<Ref> && refs);
};
template<typename Ref>
StorePathSet PathReferences<Ref>::referencesPossiblyToSelf(const Ref & self) const
{
StorePathSet refs { references };
if (hasSelfReference)
refs.insert(self);
return refs;
}
template<typename Ref>
void PathReferences<Ref>::insertReferencePossiblyToSelf(const Ref & self, Ref && ref)
{
if (ref == self)
hasSelfReference = true;
else
references.insert(std::move(ref));
}
template<typename Ref>
void PathReferences<Ref>::setReferencesPossiblyToSelf(const Ref & self, std::set<Ref> && refs)
{
if (refs.count(self))
hasSelfReference = true;
refs.erase(self);
references = refs;
}
/*
* 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;
};
struct FixedOutputInfo : FixedOutputHash {
// References for the paths
PathReferences<StorePath> references;
};
typedef std::variant<
TextInfo,
FixedOutputInfo
> ContentAddressWithReferences;
ContentAddressWithReferences caWithoutRefs(const ContentAddress &);
struct StorePathDescriptor {
std::string name;
ContentAddressWithReferences info;
bool operator == (const StorePathDescriptor & other) const
{
return name == other.name;
// FIXME second field
}
bool operator < (const StorePathDescriptor & other) const
{
return name < other.name;
// FIXME second field
}
};
}
|