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
|
#include "command.hh"
#include "common-args.hh"
#include "shared.hh"
#include "store-api.hh"
#include "progress-bar.hh"
#include "fs-accessor.hh"
using namespace nix;
static std::string hilite(const std::string & s, size_t pos, size_t len)
{
return
std::string(s, 0, pos)
+ ANSI_RED
+ std::string(s, pos, len)
+ ANSI_NORMAL
+ std::string(s, pos + len);
}
struct CmdWhyDepends : SourceExprCommand
{
std::string _package, _dependency;
CmdWhyDepends()
{
expectArg("package", &_package);
expectArg("dependency", &_dependency);
}
std::string name() override
{
return "why-depends";
}
std::string description() override
{
return "show why a package has another package in its closure";
}
Examples examples() override
{
return {
Example{
"To show which files in Hello's closure depend on Glibc:",
"nix why-depends nixpkgs.hello nixpkgs.glibc"
},
};
}
void run(ref<Store> store) override
{
auto package = parseInstallable(*this, store, _package, false);
auto packagePath = toStorePath(store, Build, package);
auto dependency = parseInstallable(*this, store, _dependency, false);
auto dependencyPath = toStorePath(store, NoBuild, dependency);
auto dependencyPathHash = storePathToHash(dependencyPath);
PathSet closure;
store->computeFSClosure({packagePath}, closure, false, false);
if (!closure.count(dependencyPath)) {
printError("'%s' does not depend on '%s'", package->what(), dependency->what());
return;
}
stopProgressBar(); // FIXME
auto accessor = store->getFSAccessor();
// FIXME: show the path through the dependency graph.
bool first = true;
for (auto & path : closure) {
if (path == dependencyPath && packagePath != dependencyPath)
continue;
if (!store->queryPathInfo(path)->references.count(dependencyPath))
continue;
if (!first) std::cerr << "\n";
first = false;
std::cerr << fmt("%s:\n", path);
std::function<void(const Path &)> recurse;
recurse = [&](const Path & p) {
auto st = accessor->stat(p);
auto p2 = p == path ? "/" : std::string(p, path.size() + 1);
if (st.type == FSAccessor::Type::tDirectory) {
auto names = accessor->readDirectory(p);
for (auto & name : names)
recurse(p + "/" + name);
}
else if (st.type == FSAccessor::Type::tRegular) {
auto contents = accessor->readFile(p);
auto pos = contents.find(dependencyPathHash);
if (pos != std::string::npos) {
size_t margin = 16;
auto pos2 = pos >= margin ? pos - margin : 0;
std::string fragment;
for (char c : std::string(contents, pos2,
pos - pos2 + dependencyPathHash.size() + margin))
{
fragment += isprint(c) ? c : '.';
}
std::cerr << fmt(" %s: …%s…\n",
p2,
hilite(fragment, pos - pos2, storePathHashLen));
}
}
else if (st.type == FSAccessor::Type::tSymlink) {
auto target = accessor->readLink(p);
auto pos = target.find(dependencyPathHash);
if (pos != std::string::npos) {
std::cerr << fmt(" %s -> %s\n", p2, hilite(target, pos, storePathHashLen));
}
}
};
recurse(path);
}
}
};
static RegisterCommand r1(make_ref<CmdWhyDepends>());
|
