diff --git a/flake.nix b/flake.nix index 5c00f744e..ed622ec86 100644 --- a/flake.nix +++ b/flake.nix @@ -489,12 +489,7 @@ ''; */ - }; - - checks = forAllSystems (system: { - binaryTarball = self.hydraJobs.binaryTarball.${system}; - perlBindings = self.hydraJobs.perlBindings.${system}; - installTests = + installTests = forAllSystems (system: let pkgs = nixpkgsFor.${system}; in pkgs.runCommand "install-tests" { againstSelf = testNixVersions pkgs pkgs.nix pkgs.pkgs.nix; @@ -506,7 +501,14 @@ # Disabled because the latest stable version doesn't handle # `NIX_DAEMON_SOCKET_PATH` which is required for the tests to work # againstLatestStable = testNixVersions pkgs pkgs.nix pkgs.nixStable; - } "touch $out"; + } "touch $out"); + + }; + + checks = forAllSystems (system: { + binaryTarball = self.hydraJobs.binaryTarball.${system}; + perlBindings = self.hydraJobs.perlBindings.${system}; + installTests = self.hydraJobs.installTests.${system}; }); packages = forAllSystems (system: { diff --git a/src/libstore/binary-cache-store.cc b/src/libstore/binary-cache-store.cc index 8fce94264..943132754 100644 --- a/src/libstore/binary-cache-store.cc +++ b/src/libstore/binary-cache-store.cc @@ -111,15 +111,15 @@ void BinaryCacheStore::writeNarInfo(ref narInfo) upsertFile(narInfoFile, narInfo->to_string(*this), "text/x-nix-narinfo"); - std::string hashPart(narInfo->path.hashPart()); - { auto state_(state.lock()); - state_->pathInfoCache.upsert(hashPart, PathInfoCacheValue { .value = std::shared_ptr(narInfo) }); + state_->pathInfoCache.upsert( + std::string(narInfo->path.to_string()), + PathInfoCacheValue { .value = std::shared_ptr(narInfo) }); } if (diskCache) - diskCache->upsertNarInfo(getUri(), hashPart, std::shared_ptr(narInfo)); + diskCache->upsertNarInfo(getUri(), std::string(narInfo->path.hashPart()), std::shared_ptr(narInfo)); } AutoCloseFD openFile(const Path & path) diff --git a/src/libstore/build/local-derivation-goal.cc b/src/libstore/build/local-derivation-goal.cc index fab6c3a08..2182f0bb4 100644 --- a/src/libstore/build/local-derivation-goal.cc +++ b/src/libstore/build/local-derivation-goal.cc @@ -1353,7 +1353,7 @@ void LocalDerivationGoal::startDaemon() AutoCloseFD remote = accept(daemonSocket.get(), (struct sockaddr *) &remoteAddr, &remoteAddrLen); if (!remote) { - if (errno == EINTR) continue; + if (errno == EINTR || errno == EAGAIN) continue; if (errno == EINVAL) break; throw SysError("accepting connection"); } diff --git a/src/libstore/daemon.cc b/src/libstore/daemon.cc index 4b3465da3..9f6c3da3d 100644 --- a/src/libstore/daemon.cc +++ b/src/libstore/daemon.cc @@ -625,9 +625,9 @@ static void performOp(TunnelLogger * logger, ref store, break; } + // Obsolete. case wopSyncWithGC: { logger->startWork(); - store->syncWithGC(); logger->stopWork(); to << 1; break; diff --git a/src/libstore/gc.cc b/src/libstore/gc.cc index 5a62c6529..8030c84f5 100644 --- a/src/libstore/gc.cc +++ b/src/libstore/gc.cc @@ -10,48 +10,22 @@ #include #include -#include -#include -#include +#include #include #include +#include +#include +#include +#include +#include +#include #include -#include namespace nix { -static string gcLockName = "gc.lock"; -static string gcRootsDir = "gcroots"; - - -/* Acquire the global GC lock. This is used to prevent new Nix - processes from starting after the temporary root files have been - read. To be precise: when they try to create a new temporary root - file, they will block until the garbage collector has finished / - yielded the GC lock. */ -AutoCloseFD LocalStore::openGCLock(LockType lockType) -{ - Path fnGCLock = (format("%1%/%2%") - % stateDir % gcLockName).str(); - - debug(format("acquiring global GC lock '%1%'") % fnGCLock); - - AutoCloseFD fdGCLock = open(fnGCLock.c_str(), O_RDWR | O_CREAT | O_CLOEXEC, 0600); - if (!fdGCLock) - throw SysError("opening global GC lock '%1%'", fnGCLock); - - if (!lockFile(fdGCLock.get(), lockType, false)) { - printInfo("waiting for the big garbage collector lock..."); - lockFile(fdGCLock.get(), lockType, true); - } - - /* !!! Restrict read permission on the GC root. Otherwise any - process that can open the file for reading can DoS the - collector. */ - - return fdGCLock; -} +static std::string gcSocketPath = "/gc-socket/socket"; +static std::string gcRootsDir = "gcroots"; static void makeSymlink(const Path & link, const Path & target) @@ -71,12 +45,6 @@ static void makeSymlink(const Path & link, const Path & target) } -void LocalStore::syncWithGC() -{ - AutoCloseFD fdGCLock = openGCLock(ltRead); -} - - void LocalStore::addIndirectRoot(const Path & path) { string hash = hashString(htSHA1, path).to_string(Base32, false); @@ -95,6 +63,12 @@ Path LocalFSStore::addPermRoot(const StorePath & storePath, const Path & _gcRoot "creating a garbage collector root (%1%) in the Nix store is forbidden " "(are you running nix-build inside the store?)", gcRoot); + /* Register this root with the garbage collector, if it's + running. This should be superfluous since the caller should + have registered this root yet, but let's be on the safe + side. */ + addTempRoot(storePath); + /* Don't clobber the link if it already exists and doesn't point to the Nix store. */ if (pathExists(gcRoot) && (!isLink(gcRoot) || !isInStore(readLink(gcRoot)))) @@ -102,11 +76,6 @@ Path LocalFSStore::addPermRoot(const StorePath & storePath, const Path & _gcRoot makeSymlink(gcRoot, printStorePath(storePath)); addIndirectRoot(gcRoot); - /* Grab the global GC root, causing us to block while a GC is in - progress. This prevents the set of permanent roots from - increasing while a GC is in progress. */ - syncWithGC(); - return gcRoot; } @@ -119,8 +88,6 @@ void LocalStore::addTempRoot(const StorePath & path) if (!state->fdTempRoots) { while (1) { - AutoCloseFD fdGCLock = openGCLock(ltRead); - if (pathExists(fnTempRoots)) /* It *must* be stale, since there can be no two processes with the same pid. */ @@ -128,10 +95,8 @@ void LocalStore::addTempRoot(const StorePath & path) state->fdTempRoots = openLockFile(fnTempRoots, true); - fdGCLock = -1; - - debug(format("acquiring read lock on '%1%'") % fnTempRoots); - lockFile(state->fdTempRoots.get(), ltRead, true); + debug("acquiring write lock on '%s'", fnTempRoots); + lockFile(state->fdTempRoots.get(), ltWrite, true); /* Check whether the garbage collector didn't get in our way. */ @@ -147,24 +112,55 @@ void LocalStore::addTempRoot(const StorePath & path) } - /* Upgrade the lock to a write lock. This will cause us to block - if the garbage collector is holding our lock. */ - debug(format("acquiring write lock on '%1%'") % fnTempRoots); - lockFile(state->fdTempRoots.get(), ltWrite, true); + if (!state->fdGCLock) + state->fdGCLock = openGCLock(); + restart: + FdLock gcLock(state->fdGCLock.get(), ltRead, false, ""); + + if (!gcLock.acquired) { + /* We couldn't get a shared global GC lock, so the garbage + collector is running. So we have to connect to the garbage + collector and inform it about our root. */ + if (!state->fdRootsSocket) { + auto socketPath = stateDir.get() + gcSocketPath; + debug("connecting to '%s'", socketPath); + state->fdRootsSocket = createUnixDomainSocket(); + nix::connect(state->fdRootsSocket.get(), socketPath); + } + + try { + debug("sending GC root '%s'", printStorePath(path)); + writeFull(state->fdRootsSocket.get(), printStorePath(path) + "\n", false); + char c; + readFull(state->fdRootsSocket.get(), &c, 1); + assert(c == '1'); + debug("got ack for GC root '%s'", printStorePath(path)); + } catch (SysError & e) { + /* The garbage collector may have exited, so we need to + restart. */ + if (e.errNo == EPIPE) { + debug("GC socket disconnected"); + state->fdRootsSocket.close(); + goto restart; + } + } catch (EndOfFile & e) { + debug("GC socket disconnected"); + state->fdRootsSocket.close(); + goto restart; + } + } + + /* Append the store path to the temporary roots file. */ string s = printStorePath(path) + '\0'; writeFull(state->fdTempRoots.get(), s); - - /* Downgrade to a read lock. */ - debug(format("downgrading to read lock on '%1%'") % fnTempRoots); - lockFile(state->fdTempRoots.get(), ltRead, true); } static std::string censored = "{censored}"; -void LocalStore::findTempRoots(FDs & fds, Roots & tempRoots, bool censor) +void LocalStore::findTempRoots(Roots & tempRoots, bool censor) { /* Read the `temproots' directory for per-process temporary root files. */ @@ -179,35 +175,25 @@ void LocalStore::findTempRoots(FDs & fds, Roots & tempRoots, bool censor) pid_t pid = std::stoi(i.name); debug(format("reading temporary root file '%1%'") % path); - FDPtr fd(new AutoCloseFD(open(path.c_str(), O_CLOEXEC | O_RDWR, 0666))); - if (!*fd) { + AutoCloseFD fd(open(path.c_str(), O_CLOEXEC | O_RDWR, 0666)); + if (!fd) { /* It's okay if the file has disappeared. */ if (errno == ENOENT) continue; throw SysError("opening temporary roots file '%1%'", path); } - /* This should work, but doesn't, for some reason. */ - //FDPtr fd(new AutoCloseFD(openLockFile(path, false))); - //if (*fd == -1) continue; - /* Try to acquire a write lock without blocking. This can only succeed if the owning process has died. In that case we don't care about its temporary roots. */ - if (lockFile(fd->get(), ltWrite, false)) { + if (lockFile(fd.get(), ltWrite, false)) { printInfo("removing stale temporary roots file '%1%'", path); unlink(path.c_str()); - writeFull(fd->get(), "d"); + writeFull(fd.get(), "d"); continue; } - /* Acquire a read lock. This will prevent the owning process - from upgrading to a write lock, therefore it will block in - addTempRoot(). */ - debug(format("waiting for read lock on '%1%'") % path); - lockFile(fd->get(), ltRead, true); - /* Read the entire file. */ - string contents = readFile(fd->get()); + string contents = readFile(fd.get()); /* Extract the roots. */ string::size_type pos = 0, end; @@ -218,8 +204,6 @@ void LocalStore::findTempRoots(FDs & fds, Roots & tempRoots, bool censor) tempRoots[parseStorePath(root)].emplace(censor ? censored : fmt("{temp:%d}", pid)); pos = end + 1; } - - fds.push_back(fd); /* keep open */ } } @@ -304,8 +288,7 @@ Roots LocalStore::findRoots(bool censor) Roots roots; findRootsNoTemp(roots, censor); - FDs fds; - findTempRoots(fds, roots, censor); + findTempRoots(roots, censor); return roots; } @@ -455,265 +438,139 @@ void LocalStore::findRuntimeRoots(Roots & roots, bool censor) struct GCLimitReached { }; -struct LocalStore::GCState -{ - const GCOptions & options; - GCResults & results; - StorePathSet roots; - StorePathSet tempRoots; - StorePathSet dead; - StorePathSet alive; - bool gcKeepOutputs; - bool gcKeepDerivations; - uint64_t bytesInvalidated; - bool moveToTrash = true; - bool shouldDelete; - GCState(const GCOptions & options, GCResults & results) - : options(options), results(results), bytesInvalidated(0) { } -}; - - -bool LocalStore::isActiveTempFile(const GCState & state, - const Path & path, const string & suffix) -{ - return hasSuffix(path, suffix) - && state.tempRoots.count(parseStorePath(string(path, 0, path.size() - suffix.size()))); -} - - -void LocalStore::deleteGarbage(GCState & state, const Path & path) -{ - uint64_t bytesFreed; - deletePath(path, bytesFreed); - state.results.bytesFreed += bytesFreed; -} - - -void LocalStore::deletePathRecursive(GCState & state, const Path & path) -{ - checkInterrupt(); - - uint64_t size = 0; - - auto storePath = maybeParseStorePath(path); - if (storePath && isValidPath(*storePath)) { - StorePathSet referrers; - queryReferrers(*storePath, referrers); - for (auto & i : referrers) - if (printStorePath(i) != path) deletePathRecursive(state, printStorePath(i)); - size = queryPathInfo(*storePath)->narSize; - invalidatePathChecked(*storePath); - } - - Path realPath = realStoreDir + "/" + std::string(baseNameOf(path)); - - struct stat st; - if (lstat(realPath.c_str(), &st)) { - if (errno == ENOENT) return; - throw SysError("getting status of %1%", realPath); - } - - printInfo(format("deleting '%1%'") % path); - - state.results.paths.insert(path); - - /* If the path is not a regular file or symlink, move it to the - trash directory. The move is to ensure that later (when we're - not holding the global GC lock) we can delete the path without - being afraid that the path has become alive again. Otherwise - delete it right away. */ - if (state.moveToTrash && S_ISDIR(st.st_mode)) { - // Estimate the amount freed using the narSize field. FIXME: - // if the path was not valid, need to determine the actual - // size. - try { - if (chmod(realPath.c_str(), st.st_mode | S_IWUSR) == -1) - throw SysError("making '%1%' writable", realPath); - Path tmp = trashDir + "/" + std::string(baseNameOf(path)); - if (rename(realPath.c_str(), tmp.c_str())) - throw SysError("unable to rename '%1%' to '%2%'", realPath, tmp); - state.bytesInvalidated += size; - } catch (SysError & e) { - if (e.errNo == ENOSPC) { - printInfo(format("note: can't create move '%1%': %2%") % realPath % e.msg()); - deleteGarbage(state, realPath); - } - } - } else - deleteGarbage(state, realPath); - - if (state.results.bytesFreed + state.bytesInvalidated > state.options.maxFreed) { - printInfo(format("deleted or invalidated more than %1% bytes; stopping") % state.options.maxFreed); - throw GCLimitReached(); - } -} - - -bool LocalStore::canReachRoot(GCState & state, StorePathSet & visited, const StorePath & path) -{ - if (visited.count(path)) return false; - - if (state.alive.count(path)) return true; - - if (state.dead.count(path)) return false; - - if (state.roots.count(path)) { - debug("cannot delete '%1%' because it's a root", printStorePath(path)); - state.alive.insert(path); - return true; - } - - visited.insert(path); - - if (!isValidPath(path)) return false; - - StorePathSet incoming; - - /* Don't delete this path if any of its referrers are alive. */ - queryReferrers(path, incoming); - - /* If keep-derivations is set and this is a derivation, then - don't delete the derivation if any of the outputs are alive. */ - if (state.gcKeepDerivations && path.isDerivation()) { - for (auto & [name, maybeOutPath] : queryPartialDerivationOutputMap(path)) - if (maybeOutPath && - isValidPath(*maybeOutPath) && - queryPathInfo(*maybeOutPath)->deriver == path - ) - incoming.insert(*maybeOutPath); - } - - /* If keep-outputs is set, then don't delete this path if there - are derivers of this path that are not garbage. */ - if (state.gcKeepOutputs) { - auto derivers = queryValidDerivers(path); - for (auto & i : derivers) - incoming.insert(i); - } - - for (auto & i : incoming) - if (i != path) - if (canReachRoot(state, visited, i)) { - state.alive.insert(path); - return true; - } - - return false; -} - - -void LocalStore::tryToDelete(GCState & state, const Path & path) -{ - checkInterrupt(); - - auto realPath = realStoreDir + "/" + std::string(baseNameOf(path)); - if (realPath == linksDir || realPath == trashDir) return; - - //Activity act(*logger, lvlDebug, format("considering whether to delete '%1%'") % path); - - auto storePath = maybeParseStorePath(path); - - if (!storePath || !isValidPath(*storePath)) { - /* A lock file belonging to a path that we're building right - now isn't garbage. */ - if (isActiveTempFile(state, path, ".lock")) return; - - /* Don't delete .chroot directories for derivations that are - currently being built. */ - if (isActiveTempFile(state, path, ".chroot")) return; - - /* Don't delete .check directories for derivations that are - currently being built, because we may need to run - diff-hook. */ - if (isActiveTempFile(state, path, ".check")) return; - } - - StorePathSet visited; - - if (storePath && canReachRoot(state, visited, *storePath)) { - debug("cannot delete '%s' because it's still reachable", path); - } else { - /* No path we visited was a root, so everything is garbage. - But we only delete ‘path’ and its referrers here so that - ‘nix-store --delete’ doesn't have the unexpected effect of - recursing into derivations and outputs. */ - for (auto & i : visited) - state.dead.insert(i); - if (state.shouldDelete) - deletePathRecursive(state, path); - } -} - - -/* Unlink all files in /nix/store/.links that have a link count of 1, - which indicates that there are no other links and so they can be - safely deleted. FIXME: race condition with optimisePath(): we - might see a link count of 1 just before optimisePath() increases - the link count. */ -void LocalStore::removeUnusedLinks(const GCState & state) -{ - AutoCloseDir dir(opendir(linksDir.c_str())); - if (!dir) throw SysError("opening directory '%1%'", linksDir); - - int64_t actualSize = 0, unsharedSize = 0; - - struct dirent * dirent; - while (errno = 0, dirent = readdir(dir.get())) { - checkInterrupt(); - string name = dirent->d_name; - if (name == "." || name == "..") continue; - Path path = linksDir + "/" + name; - - auto st = lstat(path); - - if (st.st_nlink != 1) { - actualSize += st.st_size; - unsharedSize += (st.st_nlink - 1) * st.st_size; - continue; - } - - printMsg(lvlTalkative, format("deleting unused link '%1%'") % path); - - if (unlink(path.c_str()) == -1) - throw SysError("deleting '%1%'", path); - - state.results.bytesFreed += st.st_size; - } - - struct stat st; - if (stat(linksDir.c_str(), &st) == -1) - throw SysError("statting '%1%'", linksDir); - int64_t overhead = st.st_blocks * 512ULL; - - printInfo("note: currently hard linking saves %.2f MiB", - ((unsharedSize - actualSize - overhead) / (1024.0 * 1024.0))); -} - - void LocalStore::collectGarbage(const GCOptions & options, GCResults & results) { - GCState state(options, results); - state.gcKeepOutputs = settings.gcKeepOutputs; - state.gcKeepDerivations = settings.gcKeepDerivations; + bool shouldDelete = options.action == GCOptions::gcDeleteDead || options.action == GCOptions::gcDeleteSpecific; + bool gcKeepOutputs = settings.gcKeepOutputs; + bool gcKeepDerivations = settings.gcKeepDerivations; + + StorePathSet roots, dead, alive; + + struct Shared + { + // The temp roots only store the hash part to make it easier to + // ignore suffixes like '.lock', '.chroot' and '.check'. + std::unordered_set tempRoots; + + // Hash part of the store path currently being deleted, if + // any. + std::optional pending; + }; + + Sync _shared; + + std::condition_variable wakeup; /* Using `--ignore-liveness' with `--delete' can have unintended consequences if `keep-outputs' or `keep-derivations' are true (the garbage collector will recurse into deleting the outputs or derivers, respectively). So disable them. */ if (options.action == GCOptions::gcDeleteSpecific && options.ignoreLiveness) { - state.gcKeepOutputs = false; - state.gcKeepDerivations = false; + gcKeepOutputs = false; + gcKeepDerivations = false; } - state.shouldDelete = options.action == GCOptions::gcDeleteDead || options.action == GCOptions::gcDeleteSpecific; - - if (state.shouldDelete) + if (shouldDelete) deletePath(reservedPath); - /* Acquire the global GC root. This prevents - a) New roots from being added. - b) Processes from creating new temporary root files. */ - AutoCloseFD fdGCLock = openGCLock(ltWrite); + /* Acquire the global GC root. Note: we don't use fdGCLock + here because then in auto-gc mode, another thread could + downgrade our exclusive lock. */ + auto fdGCLock = openGCLock(); + FdLock gcLock(fdGCLock.get(), ltWrite, true, "waiting for the big garbage collector lock..."); + + /* Start the server for receiving new roots. */ + auto socketPath = stateDir.get() + gcSocketPath; + createDirs(dirOf(socketPath)); + auto fdServer = createUnixDomainSocket(socketPath, 0666); + + if (fcntl(fdServer.get(), F_SETFL, fcntl(fdServer.get(), F_GETFL) | O_NONBLOCK) == -1) + throw SysError("making socket '%1%' non-blocking", socketPath); + + Pipe shutdownPipe; + shutdownPipe.create(); + + std::thread serverThread([&]() { + Sync> connections; + + Finally cleanup([&]() { + debug("GC roots server shutting down"); + while (true) { + auto item = remove_begin(*connections.lock()); + if (!item) break; + auto & [fd, thread] = *item; + shutdown(fd, SHUT_RDWR); + thread.join(); + } + }); + + while (true) { + std::vector fds; + fds.push_back({.fd = shutdownPipe.readSide.get(), .events = POLLIN}); + fds.push_back({.fd = fdServer.get(), .events = POLLIN}); + auto count = poll(fds.data(), fds.size(), -1); + assert(count != -1); + + if (fds[0].revents) + /* Parent is asking us to quit. */ + break; + + if (fds[1].revents) { + /* Accept a new connection. */ + assert(fds[1].revents & POLLIN); + AutoCloseFD fdClient = accept(fdServer.get(), nullptr, nullptr); + if (!fdClient) continue; + + /* Process the connection in a separate thread. */ + auto fdClient_ = fdClient.get(); + std::thread clientThread([&, fdClient = std::move(fdClient)]() { + Finally cleanup([&]() { + auto conn(connections.lock()); + auto i = conn->find(fdClient.get()); + if (i != conn->end()) { + i->second.detach(); + conn->erase(i); + } + }); + + while (true) { + try { + auto path = readLine(fdClient.get()); + auto storePath = maybeParseStorePath(path); + if (storePath) { + debug("got new GC root '%s'", path); + auto hashPart = std::string(storePath->hashPart()); + auto shared(_shared.lock()); + shared->tempRoots.insert(hashPart); + /* If this path is currently being + deleted, then we have to wait until + deletion is finished to ensure that + the client doesn't start + re-creating it before we're + done. FIXME: ideally we would use a + FD for this so we don't block the + poll loop. */ + while (shared->pending == hashPart) { + debug("synchronising with deletion of path '%s'", path); + shared.wait(wakeup); + } + } else + printError("received garbage instead of a root from client"); + writeFull(fdClient.get(), "1", false); + } catch (Error &) { break; } + } + }); + + connections.lock()->insert({fdClient_, std::move(clientThread)}); + } + } + }); + + Finally stopServer([&]() { + writeFull(shutdownPipe.writeSide.get(), "x", false); + wakeup.notify_all(); + if (serverThread.joinable()) serverThread.join(); + }); /* Find the roots. Since we've grabbed the GC lock, the set of permanent roots cannot increase now. */ @@ -722,124 +579,256 @@ void LocalStore::collectGarbage(const GCOptions & options, GCResults & results) if (!options.ignoreLiveness) findRootsNoTemp(rootMap, true); - for (auto & i : rootMap) state.roots.insert(i.first); + for (auto & i : rootMap) roots.insert(i.first); - /* Read the temporary roots. This acquires read locks on all - per-process temporary root files. So after this point no paths - can be added to the set of temporary roots. */ - FDs fds; + /* Read the temporary roots created before we acquired the global + GC root. Any new roots will be sent to our socket. */ Roots tempRoots; - findTempRoots(fds, tempRoots, true); + findTempRoots(tempRoots, true); for (auto & root : tempRoots) { - state.tempRoots.insert(root.first); - state.roots.insert(root.first); + _shared.lock()->tempRoots.insert(std::string(root.first.hashPart())); + roots.insert(root.first); } - /* After this point the set of roots or temporary roots cannot - increase, since we hold locks on everything. So everything - that is not reachable from `roots' is garbage. */ + /* Helper function that deletes a path from the store and throws + GCLimitReached if we've deleted enough garbage. */ + auto deleteFromStore = [&](std::string_view baseName) + { + Path path = storeDir + "/" + std::string(baseName); + Path realPath = realStoreDir + "/" + std::string(baseName); - if (state.shouldDelete) { - if (pathExists(trashDir)) deleteGarbage(state, trashDir); - try { - createDirs(trashDir); - } catch (SysError & e) { - if (e.errNo == ENOSPC) { - printInfo("note: can't create trash directory: %s", e.msg()); - state.moveToTrash = false; + printInfo("deleting '%1%'", path); + + results.paths.insert(path); + + uint64_t bytesFreed; + deletePath(realPath, bytesFreed); + results.bytesFreed += bytesFreed; + + if (results.bytesFreed > options.maxFreed) { + printInfo("deleted more than %d bytes; stopping", options.maxFreed); + throw GCLimitReached(); + } + }; + + std::map referrersCache; + + /* Helper function that visits all paths reachable from `start` + via the referrers edges and optionally derivers and derivation + output edges. If none of those paths are roots, then all + visited paths are garbage and are deleted. */ + auto deleteReferrersClosure = [&](const StorePath & start) { + StorePathSet visited; + std::queue todo; + + /* Wake up any GC client waiting for deletion of the paths in + 'visited' to finish. */ + Finally releasePending([&]() { + auto shared(_shared.lock()); + shared->pending.reset(); + wakeup.notify_all(); + }); + + auto enqueue = [&](const StorePath & path) { + if (visited.insert(path).second) + todo.push(path); + }; + + enqueue(start); + + while (auto path = pop(todo)) { + checkInterrupt(); + + /* Bail out if we've previously discovered that this path + is alive. */ + if (alive.count(*path)) { + alive.insert(start); + return; + } + + /* If we've previously deleted this path, we don't have to + handle it again. */ + if (dead.count(*path)) continue; + + auto markAlive = [&]() + { + alive.insert(*path); + alive.insert(start); + try { + StorePathSet closure; + computeFSClosure(*path, closure); + for (auto & p : closure) + alive.insert(p); + } catch (InvalidPath &) { } + }; + + /* If this is a root, bail out. */ + if (roots.count(*path)) { + debug("cannot delete '%s' because it's a root", printStorePath(*path)); + return markAlive(); + } + + if (options.action == GCOptions::gcDeleteSpecific + && !options.pathsToDelete.count(*path)) + return; + + { + auto hashPart = std::string(path->hashPart()); + auto shared(_shared.lock()); + if (shared->tempRoots.count(hashPart)) { + debug("cannot delete '%s' because it's a temporary root", printStorePath(*path)); + return markAlive(); + } + shared->pending = hashPart; + } + + if (isValidPath(*path)) { + + /* Visit the referrers of this path. */ + auto i = referrersCache.find(*path); + if (i == referrersCache.end()) { + StorePathSet referrers; + queryReferrers(*path, referrers); + referrersCache.emplace(*path, std::move(referrers)); + i = referrersCache.find(*path); + } + for (auto & p : i->second) + enqueue(p); + + /* If keep-derivations is set and this is a + derivation, then visit the derivation outputs. */ + if (gcKeepDerivations && path->isDerivation()) { + for (auto & [name, maybeOutPath] : queryPartialDerivationOutputMap(*path)) + if (maybeOutPath && + isValidPath(*maybeOutPath) && + queryPathInfo(*maybeOutPath)->deriver == *path) + enqueue(*maybeOutPath); + } + + /* If keep-outputs is set, then visit the derivers. */ + if (gcKeepOutputs) { + auto derivers = queryValidDerivers(*path); + for (auto & i : derivers) + enqueue(i); + } } } - } - /* Now either delete all garbage paths, or just the specified + for (auto & path : topoSortPaths(visited)) { + if (!dead.insert(path).second) continue; + if (shouldDelete) { + invalidatePathChecked(path); + deleteFromStore(path.to_string()); + referrersCache.erase(path); + } + } + }; + + /* Synchronisation point for testing, see tests/gc-concurrent.sh. */ + if (auto p = getEnv("_NIX_TEST_GC_SYNC")) + readFile(*p); + + /* Either delete all garbage paths, or just the specified paths (for gcDeleteSpecific). */ - if (options.action == GCOptions::gcDeleteSpecific) { for (auto & i : options.pathsToDelete) { - tryToDelete(state, printStorePath(i)); - if (state.dead.find(i) == state.dead.end()) + deleteReferrersClosure(i); + if (!dead.count(i)) throw Error( - "cannot delete path '%1%' since it is still alive. " - "To find out why use: " + "Cannot delete path '%1%' since it is still alive. " + "To find out why, use: " "nix-store --query --roots", printStorePath(i)); } } else if (options.maxFreed > 0) { - if (state.shouldDelete) + if (shouldDelete) printInfo("deleting garbage..."); else printInfo("determining live/dead paths..."); try { - AutoCloseDir dir(opendir(realStoreDir.get().c_str())); if (!dir) throw SysError("opening directory '%1%'", realStoreDir); - /* Read the store and immediately delete all paths that - aren't valid. When using --max-freed etc., deleting - invalid paths is preferred over deleting unreachable - paths, since unreachable paths could become reachable - again. We don't use readDirectory() here so that GCing - can start faster. */ + /* Read the store and delete all paths that are invalid or + unreachable. We don't use readDirectory() here so that + GCing can start faster. */ + auto linksName = baseNameOf(linksDir); Paths entries; struct dirent * dirent; while (errno = 0, dirent = readdir(dir.get())) { checkInterrupt(); string name = dirent->d_name; - if (name == "." || name == "..") continue; - Path path = storeDir + "/" + name; - auto storePath = maybeParseStorePath(path); - if (storePath && isValidPath(*storePath)) - entries.push_back(path); + if (name == "." || name == ".." || name == linksName) continue; + + if (auto storePath = maybeParseStorePath(storeDir + "/" + name)) + deleteReferrersClosure(*storePath); else - tryToDelete(state, path); + deleteFromStore(name); + } - - dir.reset(); - - /* Now delete the unreachable valid paths. Randomise the - order in which we delete entries to make the collector - less biased towards deleting paths that come - alphabetically first (e.g. /nix/store/000...). This - matters when using --max-freed etc. */ - vector entries_(entries.begin(), entries.end()); - std::mt19937 gen(1); - std::shuffle(entries_.begin(), entries_.end(), gen); - - for (auto & i : entries_) - tryToDelete(state, i); - } catch (GCLimitReached & e) { } } - if (state.options.action == GCOptions::gcReturnLive) { - for (auto & i : state.alive) - state.results.paths.insert(printStorePath(i)); + if (options.action == GCOptions::gcReturnLive) { + for (auto & i : alive) + results.paths.insert(printStorePath(i)); return; } - if (state.options.action == GCOptions::gcReturnDead) { - for (auto & i : state.dead) - state.results.paths.insert(printStorePath(i)); + if (options.action == GCOptions::gcReturnDead) { + for (auto & i : dead) + results.paths.insert(printStorePath(i)); return; } - /* Allow other processes to add to the store from here on. */ - fdGCLock = -1; - fds.clear(); - - /* Delete the trash directory. */ - printInfo(format("deleting '%1%'") % trashDir); - deleteGarbage(state, trashDir); - - /* Clean up the links directory. */ + /* Unlink all files in /nix/store/.links that have a link count of 1, + which indicates that there are no other links and so they can be + safely deleted. FIXME: race condition with optimisePath(): we + might see a link count of 1 just before optimisePath() increases + the link count. */ if (options.action == GCOptions::gcDeleteDead || options.action == GCOptions::gcDeleteSpecific) { printInfo("deleting unused links..."); - removeUnusedLinks(state); + + AutoCloseDir dir(opendir(linksDir.c_str())); + if (!dir) throw SysError("opening directory '%1%'", linksDir); + + int64_t actualSize = 0, unsharedSize = 0; + + struct dirent * dirent; + while (errno = 0, dirent = readdir(dir.get())) { + checkInterrupt(); + string name = dirent->d_name; + if (name == "." || name == "..") continue; + Path path = linksDir + "/" + name; + + auto st = lstat(path); + + if (st.st_nlink != 1) { + actualSize += st.st_size; + unsharedSize += (st.st_nlink - 1) * st.st_size; + continue; + } + + printMsg(lvlTalkative, format("deleting unused link '%1%'") % path); + + if (unlink(path.c_str()) == -1) + throw SysError("deleting '%1%'", path); + + results.bytesFreed += st.st_size; + } + + struct stat st; + if (stat(linksDir.c_str(), &st) == -1) + throw SysError("statting '%1%'", linksDir); + int64_t overhead = st.st_blocks * 512ULL; + + printInfo("note: currently hard linking saves %.2f MiB", + ((unsharedSize - actualSize - overhead) / (1024.0 * 1024.0))); } /* While we're at it, vacuum the database. */ diff --git a/src/libstore/local-store.cc b/src/libstore/local-store.cc index 1e3b5482e..225a19e1e 100644 --- a/src/libstore/local-store.cc +++ b/src/libstore/local-store.cc @@ -145,7 +145,6 @@ LocalStore::LocalStore(const Params & params) , linksDir(realStoreDir + "/.links") , reservedPath(dbDir + "/reserved") , schemaPath(dbDir + "/schema") - , trashDir(realStoreDir + "/trash") , tempRootsDir(stateDir + "/temproots") , fnTempRoots(fmt("%s/%d", tempRootsDir, getpid())) , locksHeld(tokenizeString(getEnv("NIX_HELD_LOCKS").value_or(""))) @@ -386,6 +385,16 @@ LocalStore::LocalStore(const Params & params) } +AutoCloseFD LocalStore::openGCLock() +{ + Path fnGCLock = stateDir + "/gc.lock"; + auto fdGCLock = open(fnGCLock.c_str(), O_RDWR | O_CREAT | O_CLOEXEC, 0600); + if (!fdGCLock) + throw SysError("opening global GC lock '%1%'", fnGCLock); + return fdGCLock; +} + + LocalStore::~LocalStore() { std::shared_future future; @@ -825,7 +834,7 @@ uint64_t LocalStore::addValidPath(State & state, { auto state_(Store::state.lock()); - state_->pathInfoCache.upsert(std::string(info.path.hashPart()), + state_->pathInfoCache.upsert(std::string(info.path.to_string()), PathInfoCacheValue{ .value = std::make_shared(info) }); } @@ -1198,7 +1207,7 @@ void LocalStore::invalidatePath(State & state, const StorePath & path) { auto state_(Store::state.lock()); - state_->pathInfoCache.erase(std::string(path.hashPart())); + state_->pathInfoCache.erase(std::string(path.to_string())); } } @@ -1505,7 +1514,8 @@ bool LocalStore::verifyStore(bool checkContents, RepairFlag repair) /* Acquire the global GC lock to get a consistent snapshot of existing and valid paths. */ - AutoCloseFD fdGCLock = openGCLock(ltWrite); + auto fdGCLock = openGCLock(); + FdLock gcLock(fdGCLock.get(), ltRead, true, "waiting for the big garbage collector lock..."); StringSet store; for (auto & i : readDirectory(realStoreDir)) store.insert(i.name); @@ -1516,8 +1526,6 @@ bool LocalStore::verifyStore(bool checkContents, RepairFlag repair) StorePathSet validPaths; PathSet done; - fdGCLock = -1; - for (auto & i : queryAllValidPaths()) verifyPath(printStorePath(i), store, done, validPaths, repair, errors); diff --git a/src/libstore/local-store.hh b/src/libstore/local-store.hh index a01d48c4b..301425eb1 100644 --- a/src/libstore/local-store.hh +++ b/src/libstore/local-store.hh @@ -58,9 +58,15 @@ private: struct Stmts; std::unique_ptr stmts; + /* The global GC lock */ + AutoCloseFD fdGCLock; + /* The file to which we write our temporary roots. */ AutoCloseFD fdTempRoots; + /* Connection to the garbage collector. */ + AutoCloseFD fdRootsSocket; + /* The last time we checked whether to do an auto-GC, or an auto-GC finished. */ std::chrono::time_point lastGCCheck; @@ -87,7 +93,6 @@ public: const Path linksDir; const Path reservedPath; const Path schemaPath; - const Path trashDir; const Path tempRootsDir; const Path fnTempRoots; @@ -149,14 +154,11 @@ public: void addIndirectRoot(const Path & path) override; - void syncWithGC() override; - private: - typedef std::shared_ptr FDPtr; - typedef list FDs; + void findTempRoots(Roots & roots, bool censor); - void findTempRoots(FDs & fds, Roots & roots, bool censor); + AutoCloseFD openGCLock(); public: @@ -236,29 +238,12 @@ private: PathSet queryValidPathsOld(); ValidPathInfo queryPathInfoOld(const Path & path); - struct GCState; - - void deleteGarbage(GCState & state, const Path & path); - - void tryToDelete(GCState & state, const Path & path); - - bool canReachRoot(GCState & state, StorePathSet & visited, const StorePath & path); - - void deletePathRecursive(GCState & state, const Path & path); - - bool isActiveTempFile(const GCState & state, - const Path & path, const string & suffix); - - AutoCloseFD openGCLock(LockType lockType); - void findRoots(const Path & path, unsigned char type, Roots & roots); void findRootsNoTemp(Roots & roots, bool censor); void findRuntimeRoots(Roots & roots, bool censor); - void removeUnusedLinks(const GCState & state); - Path createTempDirInStore(); void checkDerivationOutputs(const StorePath & drvPath, const Derivation & drv); diff --git a/src/libstore/misc.cc b/src/libstore/misc.cc index f184dd857..32786e963 100644 --- a/src/libstore/misc.cc +++ b/src/libstore/misc.cc @@ -239,12 +239,11 @@ StorePaths Store::topoSortPaths(const StorePathSet & paths) { return topoSort(paths, {[&](const StorePath & path) { - StorePathSet references; try { - references = queryPathInfo(path)->references; + return queryPathInfo(path)->references; } catch (InvalidPath &) { + return StorePathSet(); } - return references; }}, {[&](const StorePath & path, const StorePath & parent) { return BuildError( diff --git a/src/libstore/pathlocks.cc b/src/libstore/pathlocks.cc index 926f4ea1e..2da74e262 100644 --- a/src/libstore/pathlocks.cc +++ b/src/libstore/pathlocks.cc @@ -176,4 +176,17 @@ void PathLocks::setDeletion(bool deletePaths) } +FdLock::FdLock(int fd, LockType lockType, bool wait, std::string_view waitMsg) + : fd(fd) +{ + if (wait) { + if (!lockFile(fd, lockType, false)) { + printInfo("%s", waitMsg); + acquired = lockFile(fd, lockType, true); + } + } else + acquired = lockFile(fd, lockType, false); +} + + } diff --git a/src/libstore/pathlocks.hh b/src/libstore/pathlocks.hh index 411da0222..919c8904c 100644 --- a/src/libstore/pathlocks.hh +++ b/src/libstore/pathlocks.hh @@ -35,4 +35,18 @@ public: void setDeletion(bool deletePaths); }; +struct FdLock +{ + int fd; + bool acquired = false; + + FdLock(int fd, LockType lockType, bool wait, std::string_view waitMsg); + + ~FdLock() + { + if (acquired) + lockFile(fd, ltNone, false); + } +}; + } diff --git a/src/libstore/remote-store.cc b/src/libstore/remote-store.cc index fa5ea8af7..7decc059c 100644 --- a/src/libstore/remote-store.cc +++ b/src/libstore/remote-store.cc @@ -797,15 +797,6 @@ void RemoteStore::addIndirectRoot(const Path & path) } -void RemoteStore::syncWithGC() -{ - auto conn(getConnection()); - conn->to << wopSyncWithGC; - conn.processStderr(); - readInt(conn->from); -} - - Roots RemoteStore::findRoots(bool censor) { auto conn(getConnection()); diff --git a/src/libstore/remote-store.hh b/src/libstore/remote-store.hh index ac1eaa19e..a3036e6b0 100644 --- a/src/libstore/remote-store.hh +++ b/src/libstore/remote-store.hh @@ -101,8 +101,6 @@ public: void addIndirectRoot(const Path & path) override; - void syncWithGC() override; - Roots findRoots(bool censor) override; void collectGarbage(const GCOptions & options, GCResults & results) override; diff --git a/src/libstore/store-api.cc b/src/libstore/store-api.cc index 3338cdc1b..b0d3688ce 100644 --- a/src/libstore/store-api.cc +++ b/src/libstore/store-api.cc @@ -414,11 +414,9 @@ StorePathSet Store::queryDerivationOutputs(const StorePath & path) bool Store::isValidPath(const StorePath & storePath) { - std::string hashPart(storePath.hashPart()); - { auto state_(state.lock()); - auto res = state_->pathInfoCache.get(hashPart); + auto res = state_->pathInfoCache.get(std::string(storePath.to_string())); if (res && res->isKnownNow()) { stats.narInfoReadAverted++; return res->didExist(); @@ -426,11 +424,11 @@ bool Store::isValidPath(const StorePath & storePath) } if (diskCache) { - auto res = diskCache->lookupNarInfo(getUri(), hashPart); + auto res = diskCache->lookupNarInfo(getUri(), std::string(storePath.hashPart())); if (res.first != NarInfoDiskCache::oUnknown) { stats.narInfoReadAverted++; auto state_(state.lock()); - state_->pathInfoCache.upsert(hashPart, + state_->pathInfoCache.upsert(std::string(storePath.to_string()), res.first == NarInfoDiskCache::oInvalid ? PathInfoCacheValue{} : PathInfoCacheValue { .value = res.second }); return res.first == NarInfoDiskCache::oValid; } @@ -440,7 +438,7 @@ bool Store::isValidPath(const StorePath & storePath) if (diskCache && !valid) // FIXME: handle valid = true case. - diskCache->upsertNarInfo(getUri(), hashPart, 0); + diskCache->upsertNarInfo(getUri(), std::string(storePath.hashPart()), 0); return valid; } @@ -487,13 +485,11 @@ static bool goodStorePath(const StorePath & expected, const StorePath & actual) void Store::queryPathInfo(const StorePath & storePath, Callback> callback) noexcept { - std::string hashPart; + auto hashPart = std::string(storePath.hashPart()); try { - hashPart = storePath.hashPart(); - { - auto res = state.lock()->pathInfoCache.get(hashPart); + auto res = state.lock()->pathInfoCache.get(std::string(storePath.to_string())); if (res && res->isKnownNow()) { stats.narInfoReadAverted++; if (!res->didExist()) @@ -508,7 +504,7 @@ void Store::queryPathInfo(const StorePath & storePath, stats.narInfoReadAverted++; { auto state_(state.lock()); - state_->pathInfoCache.upsert(hashPart, + state_->pathInfoCache.upsert(std::string(storePath.to_string()), res.first == NarInfoDiskCache::oInvalid ? PathInfoCacheValue{} : PathInfoCacheValue{ .value = res.second }); if (res.first == NarInfoDiskCache::oInvalid || !goodStorePath(storePath, res.second->path)) @@ -523,7 +519,7 @@ void Store::queryPathInfo(const StorePath & storePath, auto callbackPtr = std::make_shared(std::move(callback)); queryPathInfoUncached(storePath, - {[this, storePathS{printStorePath(storePath)}, hashPart, callbackPtr](std::future> fut) { + {[this, storePath, hashPart, callbackPtr](std::future> fut) { try { auto info = fut.get(); @@ -533,14 +529,12 @@ void Store::queryPathInfo(const StorePath & storePath, { auto state_(state.lock()); - state_->pathInfoCache.upsert(hashPart, PathInfoCacheValue { .value = info }); + state_->pathInfoCache.upsert(std::string(storePath.to_string()), PathInfoCacheValue { .value = info }); } - auto storePath = parseStorePath(storePathS); - if (!info || !goodStorePath(storePath, info->path)) { stats.narInfoMissing++; - throw InvalidPath("path '%s' is not valid", storePathS); + throw InvalidPath("path '%s' is not valid", printStorePath(storePath)); } (*callbackPtr)(ref(info)); diff --git a/src/libstore/store-api.hh b/src/libstore/store-api.hh index 54471bdf2..7d02340df 100644 --- a/src/libstore/store-api.hh +++ b/src/libstore/store-api.hh @@ -232,7 +232,6 @@ protected: struct State { - // FIXME: fix key LRUCache pathInfoCache; }; @@ -561,26 +560,6 @@ public: virtual void addIndirectRoot(const Path & path) { unsupported("addIndirectRoot"); } - /* Acquire the global GC lock, then immediately release it. This - function must be called after registering a new permanent root, - but before exiting. Otherwise, it is possible that a running - garbage collector doesn't see the new root and deletes the - stuff we've just built. By acquiring the lock briefly, we - ensure that either: - - - The collector is already running, and so we block until the - collector is finished. The collector will know about our - *temporary* locks, which should include whatever it is we - want to register as a permanent lock. - - - The collector isn't running, or it's just started but hasn't - acquired the GC lock yet. In that case we get and release - the lock right away, then exit. The collector scans the - permanent root and sees ours. - - In either case the permanent root is seen by the collector. */ - virtual void syncWithGC() { }; - /* Find the roots of the garbage collector. Each root is a pair (link, storepath) where `link' is the path of the symlink outside of the Nix store that point to `storePath'. If diff --git a/src/libstore/uds-remote-store.cc b/src/libstore/uds-remote-store.cc index 02e81b022..5c38323cd 100644 --- a/src/libstore/uds-remote-store.cc +++ b/src/libstore/uds-remote-store.cc @@ -56,14 +56,7 @@ ref UDSRemoteStore::openConnection() auto conn = make_ref(); /* Connect to a daemon that does the privileged work for us. */ - conn->fd = socket(PF_UNIX, SOCK_STREAM - #ifdef SOCK_CLOEXEC - | SOCK_CLOEXEC - #endif - , 0); - if (!conn->fd) - throw SysError("cannot create Unix domain socket"); - closeOnExec(conn->fd.get()); + conn->fd = createUnixDomainSocket(); nix::connect(conn->fd.get(), path ? *path : settings.nixDaemonSocketFile); diff --git a/src/libutil/util.cc b/src/libutil/util.cc index 563a72c12..e99baf1fc 100644 --- a/src/libutil/util.cc +++ b/src/libutil/util.cc @@ -1670,7 +1670,7 @@ std::unique_ptr createInterruptCallback(std::function } -AutoCloseFD createUnixDomainSocket(const Path & path, mode_t mode) +AutoCloseFD createUnixDomainSocket() { AutoCloseFD fdSocket = socket(PF_UNIX, SOCK_STREAM #ifdef SOCK_CLOEXEC @@ -1679,8 +1679,14 @@ AutoCloseFD createUnixDomainSocket(const Path & path, mode_t mode) , 0); if (!fdSocket) throw SysError("cannot create Unix domain socket"); - closeOnExec(fdSocket.get()); + return fdSocket; +} + + +AutoCloseFD createUnixDomainSocket(const Path & path, mode_t mode) +{ + auto fdSocket = nix::createUnixDomainSocket(); bind(fdSocket.get(), path); @@ -1709,7 +1715,7 @@ void bind(int fd, const std::string & path) std::string base(baseNameOf(path)); if (base.size() + 1 >= sizeof(addr.sun_path)) throw Error("socket path '%s' is too long", base); - strcpy(addr.sun_path, base.c_str()); + memcpy(addr.sun_path, base.c_str(), base.size() + 1); if (bind(fd, (struct sockaddr *) &addr, sizeof(addr)) == -1) throw SysError("cannot bind to socket '%s'", path); _exit(0); @@ -1718,7 +1724,7 @@ void bind(int fd, const std::string & path) if (status != 0) throw Error("cannot bind to socket '%s'", path); } else { - strcpy(addr.sun_path, path.c_str()); + memcpy(addr.sun_path, path.c_str(), path.size() + 1); if (bind(fd, (struct sockaddr *) &addr, sizeof(addr)) == -1) throw SysError("cannot bind to socket '%s'", path); } @@ -1738,7 +1744,7 @@ void connect(int fd, const std::string & path) std::string base(baseNameOf(path)); if (base.size() + 1 >= sizeof(addr.sun_path)) throw Error("socket path '%s' is too long", base); - strcpy(addr.sun_path, base.c_str()); + memcpy(addr.sun_path, base.c_str(), base.size() + 1); if (connect(fd, (struct sockaddr *) &addr, sizeof(addr)) == -1) throw SysError("cannot connect to socket at '%s'", path); _exit(0); @@ -1747,7 +1753,7 @@ void connect(int fd, const std::string & path) if (status != 0) throw Error("cannot connect to socket at '%s'", path); } else { - strcpy(addr.sun_path, path.c_str()); + memcpy(addr.sun_path, path.c_str(), path.size() + 1); if (connect(fd, (struct sockaddr *) &addr, sizeof(addr)) == -1) throw SysError("cannot connect to socket at '%s'", path); } diff --git a/src/libutil/util.hh b/src/libutil/util.hh index 29232453f..485ff4153 100644 --- a/src/libutil/util.hh +++ b/src/libutil/util.hh @@ -511,6 +511,29 @@ std::optional get(const T & map, const typename T::key_ } +/* Remove and return the first item from a container. */ +template +std::optional remove_begin(T & c) +{ + auto i = c.begin(); + if (i == c.end()) return {}; + auto v = std::move(*i); + c.erase(i); + return v; +} + + +/* Remove and return the first item from a container. */ +template +std::optional pop(T & c) +{ + if (c.empty()) return {}; + auto v = std::move(c.front()); + c.pop(); + return v; +} + + template class Callback; @@ -571,6 +594,9 @@ extern PathFilter defaultPathFilter; /* Common initialisation performed in child processes. */ void commonChildInit(Pipe & logPipe); +/* Create a Unix domain socket. */ +AutoCloseFD createUnixDomainSocket(); + /* Create a Unix domain socket in listen mode. */ AutoCloseFD createUnixDomainSocket(const Path & path, mode_t mode); diff --git a/tests/ca/build-with-garbage-path.sh b/tests/ca/build-with-garbage-path.sh index 9aa08a899..884cd2802 100755 --- a/tests/ca/build-with-garbage-path.sh +++ b/tests/ca/build-with-garbage-path.sh @@ -8,7 +8,7 @@ requireDaemonNewerThan "2.4pre20210621" # Get the output path of `rootCA`, and put some garbage instead outPath="$(nix-build ./content-addressed.nix -A rootCA --no-out-link)" -nix-store --delete "$outPath" +nix-store --delete $(nix-store -q --referrers-closure "$outPath") touch "$outPath" # The build should correctly remove the garbage and put the expected path instead diff --git a/tests/gc-non-blocking.sh b/tests/gc-non-blocking.sh new file mode 100644 index 000000000..8b21c6f1c --- /dev/null +++ b/tests/gc-non-blocking.sh @@ -0,0 +1,33 @@ +# Test whether the collector is non-blocking, i.e. a build can run in +# parallel with it. +source common.sh + +needLocalStore "the GC test needs a synchronisation point" + +clearStore + +fifo=$TEST_ROOT/test.fifo +mkfifo "$fifo" + +dummy=$(nix store add-path ./simple.nix) + +running=$TEST_ROOT/running +touch $running + +(_NIX_TEST_GC_SYNC=$fifo nix-store --gc -vvvvv; rm $running) & +pid=$! + +sleep 2 + +outPath=$(nix-build -o "$TEST_ROOT/result" -E " + with import ./config.nix; + mkDerivation { + name = \"non-blocking\"; + buildCommand = \"set -x; test -e $running; mkdir \$out; echo > $fifo\"; + }") + +wait $pid + +(! test -e $running) +(! test -e $dummy) +test -e $outPath diff --git a/tests/gc.sh b/tests/gc.sh index cf0e2c32d..a736b63db 100644 --- a/tests/gc.sh +++ b/tests/gc.sh @@ -1,5 +1,7 @@ source common.sh +clearStore + drvPath=$(nix-instantiate dependencies.nix) outPath=$(nix-store -rvv "$drvPath") @@ -23,6 +25,12 @@ test -e $inUse if nix-store --delete $outPath; then false; fi test -e $outPath +for i in $NIX_STORE_DIR/*; do + if [[ $i =~ /trash ]]; then continue; fi # compat with old daemon + touch $i.lock + touch $i.chroot +done + nix-collect-garbage # Check that the root and its dependencies haven't been deleted. @@ -38,3 +46,7 @@ nix-collect-garbage # Check that the output has been GC'd. if test -e $outPath/foobar; then false; fi + +# Check that the store is empty. +rmdir $NIX_STORE_DIR/.links +rmdir $NIX_STORE_DIR diff --git a/tests/local.mk b/tests/local.mk index d88c3a875..8d454ee19 100644 --- a/tests/local.mk +++ b/tests/local.mk @@ -4,6 +4,7 @@ nix_tests = \ gc.sh \ ca/gc.sh \ gc-concurrent.sh \ + gc-non-blocking.sh \ gc-auto.sh \ referrers.sh user-envs.sh logging.sh nix-build.sh misc.sh fixed.sh \ gc-runtime.sh check-refs.sh filter-source.sh \ diff --git a/tests/multiple-outputs.sh b/tests/multiple-outputs.sh index 0bca12b42..0d45ad35b 100644 --- a/tests/multiple-outputs.sh +++ b/tests/multiple-outputs.sh @@ -76,7 +76,10 @@ if nix-build multiple-outputs.nix -A cyclic --no-out-link; then exit 1 fi +# Do a GC. This should leave an empty store. echo "collecting garbage..." rm $TEST_ROOT/result* nix-store --gc --keep-derivations --keep-outputs nix-store --gc --print-roots +rm -rf $NIX_STORE_DIR/.links +rmdir $NIX_STORE_DIR diff --git a/tests/repair.sh b/tests/repair.sh index 12dcde8ea..1105b446b 100644 --- a/tests/repair.sh +++ b/tests/repair.sh @@ -30,7 +30,7 @@ nix-store --verify-path $path2 chmod u+w $path2 touch $path2/bad -nix-store --delete $(nix-store -qd $path2) +nix-store --delete $(nix-store -q --referrers-closure $(nix-store -qd $path2)) (! nix-store --verify --check-contents --repair)