diff options
Diffstat (limited to 'third_party/nix/src/libstore/store-api.cc')
-rw-r--r-- | third_party/nix/src/libstore/store-api.cc | 982 |
1 files changed, 982 insertions, 0 deletions
diff --git a/third_party/nix/src/libstore/store-api.cc b/third_party/nix/src/libstore/store-api.cc new file mode 100644 index 000000000000..afdbc14e29a3 --- /dev/null +++ b/third_party/nix/src/libstore/store-api.cc @@ -0,0 +1,982 @@ +#include "store-api.hh" + +#include <future> +#include <utility> + +#include <absl/strings/match.h> +#include <absl/strings/numbers.h> +#include <absl/strings/str_split.h> +#include <glog/logging.h> + +#include "crypto.hh" +#include "derivations.hh" +#include "globals.hh" +#include "json.hh" +#include "nar-info-disk-cache.hh" +#include "thread-pool.hh" +#include "util.hh" + +namespace nix { + +bool Store::isInStore(const Path& path) const { + return isInDir(path, storeDir); +} + +bool Store::isStorePath(const Path& path) const { + return isInStore(path) && + path.size() >= storeDir.size() + 1 + storePathHashLen && + path.find('/', storeDir.size() + 1) == Path::npos; +} + +void Store::assertStorePath(const Path& path) const { + if (!isStorePath(path)) { + throw Error(format("path '%1%' is not in the Nix store") % path); + } +} + +Path Store::toStorePath(const Path& path) const { + if (!isInStore(path)) { + throw Error(format("path '%1%' is not in the Nix store") % path); + } + Path::size_type slash = path.find('/', storeDir.size() + 1); + if (slash == Path::npos) { + return path; + } + return Path(path, 0, slash); +} + +Path Store::followLinksToStore(const Path& _path) const { + Path path = absPath(_path); + while (!isInStore(path)) { + if (!isLink(path)) { + break; + } + std::string target = readLink(path); + path = absPath(target, dirOf(path)); + } + if (!isInStore(path)) { + throw Error(format("path '%1%' is not in the Nix store") % path); + } + return path; +} + +Path Store::followLinksToStorePath(const Path& path) const { + return toStorePath(followLinksToStore(path)); +} + +std::string storePathToName(const Path& path) { + auto base = baseNameOf(path); + assert(base.size() == storePathHashLen || + (base.size() > storePathHashLen && base[storePathHashLen] == '-')); + return base.size() == storePathHashLen + ? "" + : std::string(base, storePathHashLen + 1); +} + +std::string storePathToHash(const Path& path) { + auto base = baseNameOf(path); + assert(base.size() >= storePathHashLen); + return std::string(base, 0, storePathHashLen); +} + +void checkStoreName(const std::string& name) { + std::string validChars = "+-._?="; + + auto baseError = + format( + "The path name '%2%' is invalid: %3%. " + "Path names are alphanumeric and can include the symbols %1% " + "and must not begin with a period. " + "Note: If '%2%' is a source file and you cannot rename it on " + "disk, builtins.path { name = ... } can be used to give it an " + "alternative name.") % + validChars % name; + + /* Disallow names starting with a dot for possible security + reasons (e.g., "." and ".."). */ + if (std::string(name, 0, 1) == ".") { + throw Error(baseError % "it is illegal to start the name with a period"); + } + /* Disallow names longer than 211 characters. ext4’s max is 256, + but we need extra space for the hash and .chroot extensions. */ + if (name.length() > 211) { + throw Error(baseError % "name must be less than 212 characters"); + } + for (auto& i : name) { + if (!((i >= 'A' && i <= 'Z') || (i >= 'a' && i <= 'z') || + (i >= '0' && i <= '9') || validChars.find(i) != std::string::npos)) { + throw Error(baseError % (format("the '%1%' character is invalid") % i)); + } + } +} + +/* Store paths have the following form: + + <store>/<h>-<name> + + where + + <store> = the location of the Nix store, usually /nix/store + + <name> = a human readable name for the path, typically obtained + from the name attribute of the derivation, or the name of the + source file from which the store path is created. For derivation + outputs other than the default "out" output, the string "-<id>" + is suffixed to <name>. + + <h> = base-32 representation of the first 160 bits of a SHA-256 + hash of <s>; the hash part of the store name + + <s> = the string "<type>:sha256:<h2>:<store>:<name>"; + note that it includes the location of the store as well as the + name to make sure that changes to either of those are reflected + in the hash (e.g. you won't get /nix/store/<h>-name1 and + /nix/store/<h>-name2 with equal hash parts). + + <type> = one of: + "text:<r1>:<r2>:...<rN>" + for plain text files written to the store using + addTextToStore(); <r1> ... <rN> are the references of the + path. + "source" + for paths copied to the store using addToStore() when recursive + = true and hashAlgo = "sha256" + "output:<id>" + for either the outputs created by derivations, OR paths copied + to the store using addToStore() with recursive != true or + hashAlgo != "sha256" (in that case "source" is used; it's + silly, but it's done that way for compatibility). <id> is the + name of the output (usually, "out"). + + <h2> = base-16 representation of a SHA-256 hash of: + if <type> = "text:...": + the string written to the resulting store path + if <type> = "source": + the serialisation of the path from which this store path is + copied, as returned by hashPath() + if <type> = "output:<id>": + for non-fixed derivation outputs: + the derivation (see hashDerivationModulo() in + primops.cc) + for paths copied by addToStore() or produced by fixed-output + derivations: + the string "fixed:out:<rec><algo>:<hash>:", where + <rec> = "r:" for recursive (path) hashes, or "" for flat + (file) hashes + <algo> = "md5", "sha1" or "sha256" + <hash> = base-16 representation of the path or flat hash of + the contents of the path (or expected contents of the + path for fixed-output derivations) + + It would have been nicer to handle fixed-output derivations under + "source", e.g. have something like "source:<rec><algo>", but we're + stuck with this for now... + + The main reason for this way of computing names is to prevent name + collisions (for security). For instance, it shouldn't be feasible + to come up with a derivation whose output path collides with the + path for a copied source. The former would have a <s> starting with + "output:out:", while the latter would have a <s> starting with + "source:". +*/ + +Path Store::makeStorePath(const std::string& type, const Hash& hash, + const std::string& name) const { + /* e.g., "source:sha256:1abc...:/nix/store:foo.tar.gz" */ + std::string s = + type + ":" + hash.to_string(Base16) + ":" + storeDir + ":" + name; + + checkStoreName(name); + + return storeDir + "/" + + compressHash(hashString(htSHA256, s), 20).to_string(Base32, false) + + "-" + name; +} + +Path Store::makeOutputPath(const std::string& id, const Hash& hash, + const std::string& name) const { + return makeStorePath("output:" + id, hash, + name + (id == "out" ? "" : "-" + id)); +} + +Path Store::makeFixedOutputPath(bool recursive, const Hash& hash, + const std::string& name) const { + return hash.type == htSHA256 && recursive + ? makeStorePath("source", hash, name) + : makeStorePath( + "output:out", + hashString( + htSHA256, + "fixed:out:" + (recursive ? (std::string) "r:" : "") + + hash.to_string(Base16) + ":"), + name); +} + +Path Store::makeTextPath(const std::string& name, const Hash& hash, + const PathSet& references) const { + assert(hash.type == htSHA256); + /* Stuff the references (if any) into the type. This is a bit + hacky, but we can't put them in `s' since that would be + ambiguous. */ + std::string type = "text"; + for (auto& i : references) { + type += ":"; + type += i; + } + return makeStorePath(type, hash, name); +} + +std::pair<Path, Hash> Store::computeStorePathForPath(const std::string& name, + const Path& srcPath, + bool recursive, + HashType hashAlgo, + PathFilter& filter) const { + Hash h = recursive ? hashPath(hashAlgo, srcPath, filter).first + : hashFile(hashAlgo, srcPath); + Path dstPath = makeFixedOutputPath(recursive, h, name); + return std::pair<Path, Hash>(dstPath, h); +} + +Path Store::computeStorePathForText(const std::string& name, + const std::string& s, + const PathSet& references) const { + return makeTextPath(name, hashString(htSHA256, s), references); +} + +Store::Store(const Params& params) + : Config(params), state({(size_t)pathInfoCacheSize}) {} + +std::string Store::getUri() { return ""; } + +bool Store::isValidPath(const Path& storePath) { + assertStorePath(storePath); + + auto hashPart = storePathToHash(storePath); + + { + auto state_(state.lock()); + auto res = state_->pathInfoCache.get(hashPart); + if (res) { + stats.narInfoReadAverted++; + return *res != nullptr; + } + } + + if (diskCache) { + auto res = diskCache->lookupNarInfo(getUri(), hashPart); + if (res.first != NarInfoDiskCache::oUnknown) { + stats.narInfoReadAverted++; + auto state_(state.lock()); + state_->pathInfoCache.upsert( + hashPart, + res.first == NarInfoDiskCache::oInvalid ? nullptr : res.second); + return res.first == NarInfoDiskCache::oValid; + } + } + + bool valid = isValidPathUncached(storePath); + + if (diskCache && !valid) { + // FIXME: handle valid = true case. + diskCache->upsertNarInfo(getUri(), hashPart, nullptr); + } + + return valid; +} + +/* Default implementation for stores that only implement + queryPathInfoUncached(). */ +bool Store::isValidPathUncached(const Path& path) { + try { + queryPathInfo(path); + return true; + } catch (InvalidPath&) { + return false; + } +} + +ref<const ValidPathInfo> Store::queryPathInfo(const Path& storePath) { + std::promise<ref<ValidPathInfo>> promise; + + queryPathInfo(storePath, {[&](std::future<ref<ValidPathInfo>> result) { + try { + promise.set_value(result.get()); + } catch (...) { + promise.set_exception(std::current_exception()); + } + }}); + + return promise.get_future().get(); +} + +void Store::queryPathInfo(const Path& storePath, + Callback<ref<ValidPathInfo>> callback) noexcept { + std::string hashPart; + + try { + assertStorePath(storePath); + + hashPart = storePathToHash(storePath); + + { + auto res = state.lock()->pathInfoCache.get(hashPart); + if (res) { + stats.narInfoReadAverted++; + if (!*res) { + throw InvalidPath(format("path '%s' is not valid") % storePath); + } + return callback(ref<ValidPathInfo>(*res)); + } + } + + if (diskCache) { + auto res = diskCache->lookupNarInfo(getUri(), hashPart); + if (res.first != NarInfoDiskCache::oUnknown) { + stats.narInfoReadAverted++; + { + auto state_(state.lock()); + state_->pathInfoCache.upsert( + hashPart, + res.first == NarInfoDiskCache::oInvalid ? nullptr : res.second); + if (res.first == NarInfoDiskCache::oInvalid || + (res.second->path != storePath && + !storePathToName(storePath).empty())) { + throw InvalidPath(format("path '%s' is not valid") % storePath); + } + } + return callback(ref<ValidPathInfo>(res.second)); + } + } + + } catch (...) { + return callback.rethrow(); + } + + auto callbackPtr = std::make_shared<decltype(callback)>(std::move(callback)); + + queryPathInfoUncached( + storePath, {[this, storePath, hashPart, callbackPtr]( + std::future<std::shared_ptr<ValidPathInfo>> fut) { + try { + auto info = fut.get(); + + if (diskCache) { + diskCache->upsertNarInfo(getUri(), hashPart, info); + } + + { + auto state_(state.lock()); + state_->pathInfoCache.upsert(hashPart, info); + } + + if (!info || (info->path != storePath && + !storePathToName(storePath).empty())) { + stats.narInfoMissing++; + throw InvalidPath("path '%s' is not valid", storePath); + } + + (*callbackPtr)(ref<ValidPathInfo>(info)); + } catch (...) { + callbackPtr->rethrow(); + } + }}); +} + +PathSet Store::queryValidPaths(const PathSet& paths, + SubstituteFlag maybeSubstitute) { + struct State { + size_t left; + PathSet valid; + std::exception_ptr exc; + }; + + Sync<State> state_(State{paths.size(), PathSet()}); + + std::condition_variable wakeup; + ThreadPool pool; + + auto doQuery = [&](const Path& path) { + checkInterrupt(); + queryPathInfo( + path, {[path, &state_, &wakeup](std::future<ref<ValidPathInfo>> fut) { + auto state(state_.lock()); + try { + auto info = fut.get(); + state->valid.insert(path); + } catch (InvalidPath&) { + } catch (...) { + state->exc = std::current_exception(); + } + assert(state->left); + if (--state->left == 0u) { + wakeup.notify_one(); + } + }}); + }; + + for (auto& path : paths) { + pool.enqueue(std::bind(doQuery, path)); + } + + pool.process(); + + while (true) { + auto state(state_.lock()); + if (state->left == 0u) { + if (state->exc) { + std::rethrow_exception(state->exc); + } + return state->valid; + } + state.wait(wakeup); + } +} + +/* Return a string accepted by decodeValidPathInfo() that + registers the specified paths as valid. Note: it's the + responsibility of the caller to provide a closure. */ +std::string Store::makeValidityRegistration(const PathSet& paths, + bool showDerivers, bool showHash) { + std::string s = s; + + for (auto& i : paths) { + s += i + "\n"; + + auto info = queryPathInfo(i); + + if (showHash) { + s += info->narHash.to_string(Base16, false) + "\n"; + s += (format("%1%\n") % info->narSize).str(); + } + + Path deriver = showDerivers ? info->deriver : ""; + s += deriver + "\n"; + + s += (format("%1%\n") % info->references.size()).str(); + + for (auto& j : info->references) { + s += j + "\n"; + } + } + + return s; +} + +void Store::pathInfoToJSON(JSONPlaceholder& jsonOut, const PathSet& storePaths, + bool includeImpureInfo, bool showClosureSize, + AllowInvalidFlag allowInvalid) { + auto jsonList = jsonOut.list(); + + for (auto storePath : storePaths) { + auto jsonPath = jsonList.object(); + jsonPath.attr("path", storePath); + + try { + auto info = queryPathInfo(storePath); + storePath = info->path; + + jsonPath.attr("narHash", info->narHash.to_string()) + .attr("narSize", info->narSize); + + { + auto jsonRefs = jsonPath.list("references"); + for (auto& ref : info->references) { + jsonRefs.elem(ref); + } + } + + if (!info->ca.empty()) { + jsonPath.attr("ca", info->ca); + } + + std::pair<uint64_t, uint64_t> closureSizes; + + if (showClosureSize) { + closureSizes = getClosureSize(storePath); + jsonPath.attr("closureSize", closureSizes.first); + } + + if (includeImpureInfo) { + if (!info->deriver.empty()) { + jsonPath.attr("deriver", info->deriver); + } + + if (info->registrationTime != 0) { + jsonPath.attr("registrationTime", info->registrationTime); + } + + if (info->ultimate) { + jsonPath.attr("ultimate", info->ultimate); + } + + if (!info->sigs.empty()) { + auto jsonSigs = jsonPath.list("signatures"); + for (auto& sig : info->sigs) { + jsonSigs.elem(sig); + } + } + + auto narInfo = std::dynamic_pointer_cast<const NarInfo>( + std::shared_ptr<const ValidPathInfo>(info)); + + if (narInfo) { + if (!narInfo->url.empty()) { + jsonPath.attr("url", narInfo->url); + } + if (narInfo->fileHash) { + jsonPath.attr("downloadHash", narInfo->fileHash.to_string()); + } + if (narInfo->fileSize != 0u) { + jsonPath.attr("downloadSize", narInfo->fileSize); + } + if (showClosureSize) { + jsonPath.attr("closureDownloadSize", closureSizes.second); + } + } + } + + } catch (InvalidPath&) { + jsonPath.attr("valid", false); + } + } +} + +std::pair<uint64_t, uint64_t> Store::getClosureSize(const Path& storePath) { + uint64_t totalNarSize = 0; + uint64_t totalDownloadSize = 0; + PathSet closure; + computeFSClosure(storePath, closure, false, false); + for (auto& p : closure) { + auto info = queryPathInfo(p); + totalNarSize += info->narSize; + auto narInfo = std::dynamic_pointer_cast<const NarInfo>( + std::shared_ptr<const ValidPathInfo>(info)); + if (narInfo) { + totalDownloadSize += narInfo->fileSize; + } + } + return {totalNarSize, totalDownloadSize}; +} + +const Store::Stats& Store::getStats() { + { + auto state_(state.lock()); + stats.pathInfoCacheSize = state_->pathInfoCache.size(); + } + return stats; +} + +void Store::buildPaths(const PathSet& paths, BuildMode buildMode) { + for (auto& path : paths) { + if (isDerivation(path)) { + unsupported("buildPaths"); + } + } + + if (queryValidPaths(paths).size() != paths.size()) { + unsupported("buildPaths"); + } +} + +void copyStorePath(ref<Store> srcStore, const ref<Store>& dstStore, + const Path& storePath, RepairFlag repair, + CheckSigsFlag checkSigs) { + auto srcUri = srcStore->getUri(); + auto dstUri = dstStore->getUri(); + + if (srcUri == "local" || srcUri == "daemon") { + LOG(INFO) << "copying path '" << storePath << "' to '" << dstUri << "'"; + } else { + if (dstUri == "local" || dstUri == "daemon") { + LOG(INFO) << "copying path '" << storePath << "' from '" << srcUri << "'"; + } else { + LOG(INFO) << "copying path '" << storePath << "' from '" << srcUri + << "' to '" << dstUri << "'"; + } + } + + auto info = srcStore->queryPathInfo(storePath); + + uint64_t total = 0; + + if (!info->narHash) { + StringSink sink; + srcStore->narFromPath({storePath}, sink); + auto info2 = make_ref<ValidPathInfo>(*info); + info2->narHash = hashString(htSHA256, *sink.s); + if (info->narSize == 0u) { + info2->narSize = sink.s->size(); + } + if (info->ultimate) { + info2->ultimate = false; + } + info = info2; + + StringSource source(*sink.s); + dstStore->addToStore(*info, source, repair, checkSigs); + return; + } + + if (info->ultimate) { + auto info2 = make_ref<ValidPathInfo>(*info); + info2->ultimate = false; + info = info2; + } + + auto source = sinkToSource( + [&](Sink& sink) { + LambdaSink wrapperSink([&](const unsigned char* data, size_t len) { + sink(data, len); + total += len; + }); + srcStore->narFromPath({storePath}, wrapperSink); + }, + [&]() { + throw EndOfFile("NAR for '%s' fetched from '%s' is incomplete", + storePath, srcStore->getUri()); + }); + + dstStore->addToStore(*info, *source, repair, checkSigs); +} + +void copyPaths(ref<Store> srcStore, ref<Store> dstStore, + const PathSet& storePaths, RepairFlag repair, + CheckSigsFlag checkSigs, SubstituteFlag substitute) { + PathSet valid = dstStore->queryValidPaths(storePaths, substitute); + + PathSet missing; + for (auto& path : storePaths) { + if (valid.count(path) == 0u) { + missing.insert(path); + } + } + + if (missing.empty()) { + return; + } + + LOG(INFO) << "copying " << missing.size() << " paths"; + + std::atomic<size_t> nrDone{0}; + std::atomic<size_t> nrFailed{0}; + std::atomic<uint64_t> bytesExpected{0}; + std::atomic<uint64_t> nrRunning{0}; + + ThreadPool pool; + + processGraph<Path>( + pool, PathSet(missing.begin(), missing.end()), + + [&](const Path& storePath) { + if (dstStore->isValidPath(storePath)) { + nrDone++; + return PathSet(); + } + + auto info = srcStore->queryPathInfo(storePath); + + bytesExpected += info->narSize; + + return info->references; + }, + + [&](const Path& storePath) { + checkInterrupt(); + + if (!dstStore->isValidPath(storePath)) { + MaintainCount<decltype(nrRunning)> mc(nrRunning); + try { + copyStorePath(srcStore, dstStore, storePath, repair, checkSigs); + } catch (Error& e) { + nrFailed++; + if (!settings.keepGoing) { + throw e; + } + LOG(ERROR) << "could not copy " << storePath << ": " << e.what(); + return; + } + } + + nrDone++; + }); +} + +void copyClosure(const ref<Store>& srcStore, const ref<Store>& dstStore, + const PathSet& storePaths, RepairFlag repair, + CheckSigsFlag checkSigs, SubstituteFlag substitute) { + PathSet closure; + srcStore->computeFSClosure({storePaths}, closure); + copyPaths(srcStore, dstStore, closure, repair, checkSigs, substitute); +} + +ValidPathInfo decodeValidPathInfo(std::istream& str, bool hashGiven) { + ValidPathInfo info; + getline(str, info.path); + if (str.eof()) { + info.path = ""; + return info; + } + if (hashGiven) { + std::string s; + getline(str, s); + info.narHash = Hash(s, htSHA256); + getline(str, s); + if (!absl::SimpleAtoi(s, &info.narSize)) { + throw Error("number expected"); + } + } + getline(str, info.deriver); + std::string s; + int n; + getline(str, s); + if (!absl::SimpleAtoi(s, &n)) { + throw Error("number expected"); + } + while ((n--) != 0) { + getline(str, s); + info.references.insert(s); + } + if (!str || str.eof()) { + throw Error("missing input"); + } + return info; +} + +std::string showPaths(const PathSet& paths) { + std::string s; + for (auto& i : paths) { + if (!s.empty()) { + s += ", "; + } + s += "'" + i + "'"; + } + return s; +} + +std::string ValidPathInfo::fingerprint() const { + if (narSize == 0 || !narHash) { + throw Error(format("cannot calculate fingerprint of path '%s' because its " + "size/hash is not known") % + path); + } + return "1;" + path + ";" + narHash.to_string(Base32) + ";" + + std::to_string(narSize) + ";" + concatStringsSep(",", references); +} + +void ValidPathInfo::sign(const SecretKey& secretKey) { + sigs.insert(secretKey.signDetached(fingerprint())); +} + +bool ValidPathInfo::isContentAddressed(const Store& store) const { + auto warn = [&]() { + LOG(ERROR) << "warning: path '" << path + << "' claims to be content-addressed but isn't"; + }; + + if (absl::StartsWith(ca, "text:")) { + Hash hash(std::string(ca, 5)); + if (store.makeTextPath(storePathToName(path), hash, references) == path) { + return true; + } + warn(); + + } + + else if (absl::StartsWith(ca, "fixed:")) { + bool recursive = ca.compare(6, 2, "r:") == 0; + Hash hash(std::string(ca, recursive ? 8 : 6)); + if (references.empty() && + store.makeFixedOutputPath(recursive, hash, storePathToName(path)) == + path) { + return true; + } + warn(); + } + + return false; +} + +size_t ValidPathInfo::checkSignatures(const Store& store, + const PublicKeys& publicKeys) const { + if (isContentAddressed(store)) { + return maxSigs; + } + + size_t good = 0; + for (auto& sig : sigs) { + if (checkSignature(publicKeys, sig)) { + good++; + } + } + return good; +} + +bool ValidPathInfo::checkSignature(const PublicKeys& publicKeys, + const std::string& sig) const { + return verifyDetached(fingerprint(), sig, publicKeys); +} + +Strings ValidPathInfo::shortRefs() const { + Strings refs; + for (auto& r : references) { + refs.push_back(baseNameOf(r)); + } + return refs; +} + +std::string makeFixedOutputCA(bool recursive, const Hash& hash) { + return "fixed:" + (recursive ? (std::string) "r:" : "") + hash.to_string(); +} + +void Store::addToStore(const ValidPathInfo& info, Source& narSource, + RepairFlag repair, CheckSigsFlag checkSigs, + std::shared_ptr<FSAccessor> accessor) { + addToStore(info, make_ref<std::string>(narSource.drain()), repair, checkSigs, + std::move(accessor)); +} + +void Store::addToStore(const ValidPathInfo& info, const ref<std::string>& nar, + RepairFlag repair, CheckSigsFlag checkSigs, + std::shared_ptr<FSAccessor> accessor) { + StringSource source(*nar); + addToStore(info, source, repair, checkSigs, std::move(accessor)); +} + +} // namespace nix + +#include "local-store.hh" +#include "remote-store.hh" + +namespace nix { + +RegisterStoreImplementation::Implementations* + RegisterStoreImplementation::implementations = nullptr; + +/* Split URI into protocol+hierarchy part and its parameter set. */ +std::pair<std::string, Store::Params> splitUriAndParams( + const std::string& uri_) { + auto uri(uri_); + Store::Params params; + auto q = uri.find('?'); + if (q != std::string::npos) { + Strings parts = absl::StrSplit(uri.substr(q + 1), absl::ByChar('&')); + for (const auto& s : parts) { + auto e = s.find('='); + if (e != std::string::npos) { + auto value = s.substr(e + 1); + std::string decoded; + for (size_t i = 0; i < value.size();) { + if (value[i] == '%') { + if (i + 2 >= value.size()) { + throw Error("invalid URI parameter '%s'", value); + } + try { + decoded += std::stoul(std::string(value, i + 1, 2), nullptr, 16); + i += 3; + } catch (...) { + throw Error("invalid URI parameter '%s'", value); + } + } else { + decoded += value[i++]; + } + } + params[s.substr(0, e)] = decoded; + } + } + uri = uri_.substr(0, q); + } + return {uri, params}; +} + +ref<Store> openStore(const std::string& uri_, + const Store::Params& extraParams) { + auto [uri, uriParams] = splitUriAndParams(uri_); + auto params = extraParams; + params.insert(uriParams.begin(), uriParams.end()); + + for (const auto& fun : *RegisterStoreImplementation::implementations) { + auto store = fun(uri, params); + if (store) { + store->warnUnknownSettings(); + return ref<Store>(store); + } + } + + throw Error("don't know how to open Nix store '%s'", uri); +} + +StoreType getStoreType(const std::string& uri, const std::string& stateDir) { + if (uri == "daemon") { + return tDaemon; + } + if (uri == "local" || absl::StartsWith(uri, "/")) { + return tLocal; + } else if (uri.empty() || uri == "auto") { + if (access(stateDir.c_str(), R_OK | W_OK) == 0) { + return tLocal; + } + if (pathExists(settings.nixDaemonSocketFile)) { + return tDaemon; + } else { + return tLocal; + } + } else { + return tOther; + } +} + +static RegisterStoreImplementation regStore([](const std::string& uri, + const Store::Params& params) + -> std::shared_ptr<Store> { + switch (getStoreType(uri, get(params, "state", settings.nixStateDir))) { + case tDaemon: + return std::shared_ptr<Store>(std::make_shared<UDSRemoteStore>(params)); + case tLocal: { + Store::Params params2 = params; + if (absl::StartsWith(uri, "/")) { + params2["root"] = uri; + } + return std::shared_ptr<Store>(std::make_shared<LocalStore>(params2)); + } + default: + return nullptr; + } +}); + +std::list<ref<Store>> getDefaultSubstituters() { + static auto stores([]() { + std::list<ref<Store>> stores; + + StringSet done; + + auto addStore = [&](const std::string& uri) { + if (done.count(uri) != 0u) { + return; + } + done.insert(uri); + try { + stores.push_back(openStore(uri)); + } catch (Error& e) { + LOG(WARNING) << e.what(); + } + }; + + for (const auto& uri : settings.substituters.get()) { + addStore(uri); + } + + for (const auto& uri : settings.extraSubstituters.get()) { + addStore(uri); + } + + stores.sort([](ref<Store>& a, ref<Store>& b) { + return a->getPriority() < b->getPriority(); + }); + + return stores; + }()); + + return stores; +} + +} // namespace nix |