diff options
Diffstat (limited to 'third_party/nix/src/nix-prefetch-url/nix-prefetch-url.cc')
| -rw-r--r-- | third_party/nix/src/nix-prefetch-url/nix-prefetch-url.cc | 236 |
1 files changed, 236 insertions, 0 deletions
diff --git a/third_party/nix/src/nix-prefetch-url/nix-prefetch-url.cc b/third_party/nix/src/nix-prefetch-url/nix-prefetch-url.cc new file mode 100644 index 000000000000..f54706a8a011 --- /dev/null +++ b/third_party/nix/src/nix-prefetch-url/nix-prefetch-url.cc @@ -0,0 +1,236 @@ +#include "hash.hh" +#include "shared.hh" +#include "download.hh" +#include "store-api.hh" +#include "eval.hh" +#include "eval-inline.hh" +#include "common-eval-args.hh" +#include "attr-path.hh" +#include "legacy.hh" +#include "finally.hh" +#include "progress-bar.hh" + +#include <iostream> + +#include <sys/types.h> +#include <sys/stat.h> +#include <fcntl.h> + +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); +} + + +static int _main(int argc, char * * argv) +{ + { + HashType ht = htSHA256; + std::vector<string> args; + bool printPath = getEnv("PRINT_PATH") != ""; + bool fromExpr = false; + string attrPath; + bool unpack = false; + string name; + + struct MyArgs : LegacyArgs, MixEvalArgs + { + using LegacyArgs::LegacyArgs; + }; + + MyArgs myArgs(baseNameOf(argv[0]), [&](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 (*arg == "--name") + name = getArg(*arg, arg, end); + else if (*arg != "" && arg->at(0) == '-') + return false; + else + args.push_back(*arg); + return true; + }); + + myArgs.parseCmdline(argvToStrings(argc, argv)); + + initPlugins(); + + if (args.size() > 2) + throw UsageError("too many arguments"); + + Finally f([]() { stopProgressBar(); }); + + if (isatty(STDERR_FILENO)) + startProgressBar(); + + auto store = openStore(); + auto state = std::make_unique<EvalState>(myArgs.searchPath, store); + + Bindings & autoArgs = *myArgs.getAutoArgs(*state); + + /* 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()) + printInfo("warning: this does not look like a fetchurl call"); + else + unpack = state->forceString(*attr->value) == "recursive"; + + /* Extract the name. */ + if (name.empty()) { + attr = v.attrs->find(state->symbols.create("name")); + if (attr != v.attrs->end()) + name = state->forceString(*attr->value); + } + } + + /* Figure out a name in the Nix store. */ + if (name.empty()) + 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 = Hash(args[1], ht); + storePath = store->makeFixedOutputPath(unpack, expectedHash, name); + if (store->isValidPath(storePath)) + hash = expectedHash; + else + storePath.clear(); + } + + if (storePath.empty()) { + + auto actualUri = resolveMirrorUri(*state, uri); + + AutoDelete tmpDir(createTempDir(), true); + Path tmpFile = (Path) tmpDir + "/tmp"; + + /* Download the file. */ + { + AutoCloseFD fd = open(tmpFile.c_str(), O_WRONLY | O_CREAT | O_EXCL, 0600); + if (!fd) throw SysError("creating temporary file '%s'", tmpFile); + + FdSink sink(fd.get()); + + DownloadRequest req(actualUri); + req.decompress = false; + getDownloader()->download(std::move(req), sink); + } + + /* Optionally unpack the file. */ + if (unpack) { + printInfo("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 : hashFile(ht, tmpFile); + + 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 == store->makeFixedOutputPath(unpack, hash, name)); + } + + stopProgressBar(); + + if (!printPath) + printInfo(format("path is '%1%'") % storePath); + + std::cout << printHash16or32(hash) << std::endl; + if (printPath) + std::cout << storePath << std::endl; + + return 0; + } +} + +static RegisterLegacyCommand s1("nix-prefetch-url", _main); |