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
|
#include "hash.hh"
#include "shared.hh"
#include "download.hh"
#include "store-api.hh"
#include "eval.hh"
#include "eval-inline.hh"
#include "common-opts.hh"
#include "attr-path.hh"
#include <iostream>
using namespace nix;
/* If ‘uri’ starts with ‘mirror://’, then resolve it using the list of
mirrors defined in Nixpkgs. */
string resolveMirrorUri(EvalState & state, string uri)
{
if (string(uri, 0, 9) != "mirror://") return uri;
string s(uri, 9);
auto p = s.find('/');
if (p == string::npos) throw Error("invalid mirror URI");
string mirrorName(s, 0, p);
Value vMirrors;
state.eval(state.parseExprFromString("import <nixpkgs/pkgs/build-support/fetchurl/mirrors.nix>", "."), vMirrors);
state.forceAttrs(vMirrors);
auto mirrorList = vMirrors.attrs->find(state.symbols.create(mirrorName));
if (mirrorList == vMirrors.attrs->end())
throw Error(format("unknown mirror name ‘%1%’") % mirrorName);
state.forceList(*mirrorList->value);
if (mirrorList->value->listSize() < 1)
throw Error(format("mirror URI ‘%1%’ did not expand to anything") % uri);
string mirror = state.forceString(*mirrorList->value->listElems()[0]);
return mirror + (hasSuffix(mirror, "/") ? "" : "/") + string(s, p + 1);
}
int main(int argc, char * * argv)
{
return handleExceptions(argv[0], [&]() {
initNix();
initGC();
HashType ht = htSHA256;
std::vector<string> args;
Strings searchPath;
bool printPath = getEnv("PRINT_PATH") != "";
bool fromExpr = false;
string attrPath;
std::map<string, string> autoArgs_;
bool unpack = false;
parseCmdLine(argc, argv, [&](Strings::iterator & arg, const Strings::iterator & end) {
if (*arg == "--help")
showManPage("nix-prefetch-url");
else if (*arg == "--version")
printVersion("nix-prefetch-url");
else if (*arg == "--type") {
string s = getArg(*arg, arg, end);
ht = parseHashType(s);
if (ht == htUnknown)
throw UsageError(format("unknown hash type ‘%1%’") % s);
}
else if (*arg == "--print-path")
printPath = true;
else if (*arg == "--attr" || *arg == "-A") {
fromExpr = true;
attrPath = getArg(*arg, arg, end);
}
else if (*arg == "--unpack")
unpack = true;
else if (parseAutoArgs(arg, end, autoArgs_))
;
else if (parseSearchPathArg(arg, end, searchPath))
;
else if (*arg != "" && arg->at(0) == '-')
return false;
else
args.push_back(*arg);
return true;
});
if (args.size() > 2)
throw UsageError("too many arguments");
store = openStore();
EvalState state(searchPath);
Bindings & autoArgs(*evalAutoArgs(state, autoArgs_));
/* If -A is given, get the URI from the specified Nix
expression. */
string uri;
if (!fromExpr) {
if (args.empty())
throw UsageError("you must specify a URI");
uri = args[0];
} else {
Path path = resolveExprPath(lookupFileArg(state, args.empty() ? "." : args[0]));
Value vRoot;
state.evalFile(path, vRoot);
Value & v(*findAlongAttrPath(state, attrPath, autoArgs, vRoot));
state.forceAttrs(v);
/* Extract the URI. */
auto attr = v.attrs->find(state.symbols.create("urls"));
if (attr == v.attrs->end())
throw Error("attribute set does not contain a ‘urls’ attribute");
state.forceList(*attr->value);
if (attr->value->listSize() < 1)
throw Error("‘urls’ list is empty");
uri = state.forceString(*attr->value->listElems()[0]);
/* Extract the hash mode. */
attr = v.attrs->find(state.symbols.create("outputHashMode"));
if (attr == v.attrs->end())
printMsg(lvlInfo, "warning: this does not look like a fetchurl call");
else
unpack = state.forceString(*attr->value) == "recursive";
}
/* Figure out a name in the Nix store. */
auto name = baseNameOf(uri);
if (name.empty())
throw Error(format("cannot figure out file name for ‘%1%’") % uri);
/* If an expected hash is given, the file may already exist in
the store. */
Hash hash, expectedHash(ht);
Path storePath;
if (args.size() == 2) {
expectedHash = parseHash16or32(ht, args[1]);
storePath = makeFixedOutputPath(unpack, ht, expectedHash, name);
if (store->isValidPath(storePath))
hash = expectedHash;
else
storePath.clear();
}
if (storePath.empty()) {
auto actualUri = resolveMirrorUri(state, uri);
/* Download the file. */
printMsg(lvlInfo, format("downloading ‘%1%’...") % actualUri);
auto result = downloadFile(actualUri);
AutoDelete tmpDir(createTempDir(), true);
Path tmpFile = (Path) tmpDir + "/tmp";
writeFile(tmpFile, result.data);
/* Optionally unpack the file. */
if (unpack) {
printMsg(lvlInfo, "unpacking...");
Path unpacked = (Path) tmpDir + "/unpacked";
createDirs(unpacked);
if (hasSuffix(baseNameOf(uri), ".zip"))
runProgram("unzip", true, {"-qq", tmpFile, "-d", unpacked}, "");
else
// FIXME: this requires GNU tar for decompression.
runProgram("tar", true, {"xf", tmpFile, "-C", unpacked}, "");
/* If the archive unpacks to a single file/directory, then use
that as the top-level. */
auto entries = readDirectory(unpacked);
if (entries.size() == 1)
tmpFile = unpacked + "/" + entries[0].name;
else
tmpFile = unpacked;
}
/* FIXME: inefficient; addToStore() will also hash
this. */
hash = unpack ? hashPath(ht, tmpFile).first : hashString(ht, result.data);
if (expectedHash != Hash(ht) && expectedHash != hash)
throw Error(format("hash mismatch for ‘%1%’") % uri);
/* Copy the file to the Nix store. FIXME: if RemoteStore
implemented addToStoreFromDump() and downloadFile()
supported a sink, we could stream the download directly
into the Nix store. */
storePath = store->addToStore(name, tmpFile, unpack, ht);
assert(storePath == makeFixedOutputPath(unpack, ht, hash, name));
}
if (!printPath)
printMsg(lvlInfo, format("path is ‘%1%’") % storePath);
std::cout << printHash16or32(hash) << std::endl;
if (printPath)
std::cout << storePath << std::endl;
});
}
|
