about summary refs log tree commit diff
path: root/src/libstore/misc.cc
blob: 114ab565e08cbac593aca15c1ea2f7ca0f9bd157 (plain) (blame)
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
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
#include "derivations.hh"
#include "globals.hh"
#include "local-store.hh"
#include "store-api.hh"


namespace nix {


void Store::computeFSClosure(const Path & path,
    PathSet & paths, bool flipDirection, bool includeOutputs, bool includeDerivers)
{
    if (paths.find(path) != paths.end()) return;
    paths.insert(path);

    PathSet edges;

    if (flipDirection) {
        queryReferrers(path, edges);

        if (includeOutputs) {
            PathSet derivers = queryValidDerivers(path);
            for (auto & i : derivers)
                edges.insert(i);
        }

        if (includeDerivers && isDerivation(path)) {
            PathSet outputs = queryDerivationOutputs(path);
            for (auto & i : outputs)
                if (isValidPath(i) && queryPathInfo(i)->deriver == path)
                    edges.insert(i);
        }

    } else {
        auto info = queryPathInfo(path);
        edges = info->references;

        if (includeOutputs && isDerivation(path)) {
            PathSet outputs = queryDerivationOutputs(path);
            for (auto & i : outputs)
                if (isValidPath(i)) edges.insert(i);
        }

        if (includeDerivers && isValidPath(info->deriver))
            edges.insert(info->deriver);
    }

    for (auto & i : edges)
        computeFSClosure(i, paths, flipDirection, includeOutputs, includeDerivers);
}


void Store::queryMissing(const PathSet & targets,
    PathSet & willBuild, PathSet & willSubstitute, PathSet & unknown,
    unsigned long long & downloadSize, unsigned long long & narSize)
{
    downloadSize = narSize = 0;

    PathSet todo(targets.begin(), targets.end()), done;

    /* Getting substitute info has high latency when using the binary
       cache substituter.  Thus it's essential to do substitute
       queries in parallel as much as possible.  To accomplish this
       we do the following:

       - For all paths still to be processed (‘todo’), we add all
         paths for which we need info to the set ‘query’.  For an
         unbuilt derivation this is the output paths; otherwise, it's
         the path itself.

       - We get info about all paths in ‘query’ in parallel.

       - We process the results and add new items to ‘todo’ if
         necessary.  E.g. if a path is substitutable, then we need to
         get info on its references.

       - Repeat until ‘todo’ is empty.
    */

    while (!todo.empty()) {

        PathSet query, todoDrv, todoNonDrv;

        for (auto & i : todo) {
            if (done.find(i) != done.end()) continue;
            done.insert(i);

            DrvPathWithOutputs i2 = parseDrvPathWithOutputs(i);

            if (isDerivation(i2.first)) {
                if (!isValidPath(i2.first)) {
                    // FIXME: we could try to substitute p.
                    unknown.insert(i);
                    continue;
                }
                Derivation drv = derivationFromPath(i2.first);

                PathSet invalid;
                for (auto & j : drv.outputs)
                    if (wantOutput(j.first, i2.second)
                        && !isValidPath(j.second.path))
                        invalid.insert(j.second.path);
                if (invalid.empty()) continue;

                todoDrv.insert(i);
                if (settings.useSubstitutes && drv.substitutesAllowed())
                    query.insert(invalid.begin(), invalid.end());
            }

            else {
                if (isValidPath(i)) continue;
                query.insert(i);
                todoNonDrv.insert(i);
            }
        }

        todo.clear();

        SubstitutablePathInfos infos;
        querySubstitutablePathInfos(query, infos);

        for (auto & i : todoDrv) {
            DrvPathWithOutputs i2 = parseDrvPathWithOutputs(i);

            // FIXME: cache this
            Derivation drv = derivationFromPath(i2.first);

            PathSet outputs;
            bool mustBuild = false;
            if (settings.useSubstitutes && drv.substitutesAllowed()) {
                for (auto & j : drv.outputs) {
                    if (!wantOutput(j.first, i2.second)) continue;
                    if (!isValidPath(j.second.path)) {
                        if (infos.find(j.second.path) == infos.end())
                            mustBuild = true;
                        else
                            outputs.insert(j.second.path);
                    }
                }
            } else
                mustBuild = true;

            if (mustBuild) {
                willBuild.insert(i2.first);
                todo.insert(drv.inputSrcs.begin(), drv.inputSrcs.end());
                for (auto & j : drv.inputDrvs)
                    todo.insert(makeDrvPathWithOutputs(j.first, j.second));
            } else
                todoNonDrv.insert(outputs.begin(), outputs.end());
        }

        for (auto & i : todoNonDrv) {
            done.insert(i);
            SubstitutablePathInfos::iterator info = infos.find(i);
            if (info != infos.end()) {
                willSubstitute.insert(i);
                downloadSize += info->second.downloadSize;
                narSize += info->second.narSize;
                todo.insert(info->second.references.begin(), info->second.references.end());
            } else
                unknown.insert(i);
        }
    }
}


Paths Store::topoSortPaths(const PathSet & paths)
{
    Paths sorted;
    PathSet visited, parents;

    std::function<void(const Path & path)> dfsVisit;

    dfsVisit = [&](const Path & path) {
        if (parents.find(path) != parents.end())
            throw BuildError(format("cycle detected in the references of ‘%1%’") % path);

        if (visited.find(path) != visited.end()) return;
        visited.insert(path);
        parents.insert(path);

        PathSet references;
        try {
            references = queryPathInfo(path)->references;
        } catch (InvalidPath &) {
        }

        for (auto & i : references)
            /* Don't traverse into paths that don't exist.  That can
               happen due to substitutes for non-existent paths. */
            if (i != path && paths.find(i) != paths.end())
                dfsVisit(i);

        sorted.push_front(path);
        parents.erase(path);
    };

    for (auto & i : paths)
        dfsVisit(i);

    return sorted;
}


}