mirror of
https://github.com/privatevoid-net/nix-super.git
synced 2024-11-25 15:26:17 +02:00
Non-blocking garbage collector
The garbage collector no longer blocks other processes from adding/building store paths or adding GC roots. To prevent the collector from deleting store paths just added by another process, processes need to connect to the garbage collector via a Unix domain socket to register new temporary roots.
This commit is contained in:
Eelco Dolstra
parent
9947f1646a
commit
8614cf1334
11 changed files with 344 additions and 272 deletions
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@ -1353,7 +1353,7 @@ void LocalDerivationGoal::startDaemon()
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AutoCloseFD remote = accept(daemonSocket.get(),
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(struct sockaddr *) &remoteAddr, &remoteAddrLen);
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if (!remote) {
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if (errno == EINTR) continue;
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if (errno == EINTR || errno == EAGAIN) continue;
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if (errno == EINVAL) break;
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throw SysError("accepting connection");
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}
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@ -10,48 +10,22 @@
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#include <regex>
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#include <random>
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#include <sys/types.h>
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#include <sys/stat.h>
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#include <sys/statvfs.h>
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#include <climits>
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#include <errno.h>
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#include <fcntl.h>
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#include <poll.h>
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#include <sys/socket.h>
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#include <sys/stat.h>
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#include <sys/statvfs.h>
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#include <sys/types.h>
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#include <sys/un.h>
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#include <unistd.h>
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#include <climits>
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namespace nix {
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static string gcLockName = "gc.lock";
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static string gcRootsDir = "gcroots";
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/* Acquire the global GC lock. This is used to prevent new Nix
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processes from starting after the temporary root files have been
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read. To be precise: when they try to create a new temporary root
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file, they will block until the garbage collector has finished /
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yielded the GC lock. */
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AutoCloseFD LocalStore::openGCLock(LockType lockType)
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{
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Path fnGCLock = (format("%1%/%2%")
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% stateDir % gcLockName).str();
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debug(format("acquiring global GC lock '%1%'") % fnGCLock);
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AutoCloseFD fdGCLock = open(fnGCLock.c_str(), O_RDWR | O_CREAT | O_CLOEXEC, 0600);
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if (!fdGCLock)
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throw SysError("opening global GC lock '%1%'", fnGCLock);
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if (!lockFile(fdGCLock.get(), lockType, false)) {
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printInfo("waiting for the big garbage collector lock...");
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lockFile(fdGCLock.get(), lockType, true);
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}
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/* !!! Restrict read permission on the GC root. Otherwise any
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process that can open the file for reading can DoS the
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collector. */
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return fdGCLock;
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}
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static std::string gcSocketPath = "/gc-socket/socket";
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static std::string gcRootsDir = "gcroots";
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static void makeSymlink(const Path & link, const Path & target)
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@ -114,8 +88,6 @@ void LocalStore::addTempRoot(const StorePath & path)
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if (!state->fdTempRoots) {
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while (1) {
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AutoCloseFD fdGCLock = openGCLock(ltRead);
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if (pathExists(fnTempRoots))
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/* It *must* be stale, since there can be no two
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processes with the same pid. */
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@ -123,10 +95,8 @@ void LocalStore::addTempRoot(const StorePath & path)
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state->fdTempRoots = openLockFile(fnTempRoots, true);
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fdGCLock = -1;
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debug(format("acquiring read lock on '%1%'") % fnTempRoots);
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lockFile(state->fdTempRoots.get(), ltRead, true);
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debug("acquiring write lock on '%s'", fnTempRoots);
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lockFile(state->fdTempRoots.get(), ltWrite, true);
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/* Check whether the garbage collector didn't get in our
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way. */
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@ -142,24 +112,62 @@ void LocalStore::addTempRoot(const StorePath & path)
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}
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/* Upgrade the lock to a write lock. This will cause us to block
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if the garbage collector is holding our lock. */
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debug(format("acquiring write lock on '%1%'") % fnTempRoots);
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lockFile(state->fdTempRoots.get(), ltWrite, true);
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restart:
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FdLock gcLock(state->fdGCLock.get(), ltRead, false, "");
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if (!gcLock.acquired) {
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/* We couldn't get a shared global GC lock, so the garbage
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collector is running. So we have to connect to the garbage
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collector and inform it about our root. */
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if (!state->fdRootsSocket) {
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state->fdRootsSocket = createUnixDomainSocket();
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auto socketPath = stateDir.get() + gcSocketPath;
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debug("connecting to '%s'", socketPath);
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struct sockaddr_un addr;
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addr.sun_family = AF_UNIX;
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if (socketPath.size() + 1 >= sizeof(addr.sun_path))
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throw Error("socket path '%s' is too long", socketPath);
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strcpy(addr.sun_path, socketPath.c_str());
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if (::connect(state->fdRootsSocket.get(), (struct sockaddr *) &addr, sizeof(addr)) == -1)
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throw SysError("cannot connect to garbage collector at '%s'", socketPath);
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}
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try {
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debug("sending GC root '%s'", printStorePath(path));
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writeFull(state->fdRootsSocket.get(), printStorePath(path) + "\n", false);
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char c;
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readFull(state->fdRootsSocket.get(), &c, 1);
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assert(c == '1');
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debug("got ack for GC root '%s'", printStorePath(path));
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} catch (SysError & e) {
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/* The garbage collector may have exited, so we need to
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restart. */
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if (e.errNo == EPIPE) {
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debug("GC socket disconnected");
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state->fdRootsSocket.close();
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goto restart;
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}
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} catch (EndOfFile & e) {
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debug("GC socket disconnected");
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state->fdRootsSocket.close();
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goto restart;
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}
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}
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/* Append the store path to the temporary roots file. */
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string s = printStorePath(path) + '\0';
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writeFull(state->fdTempRoots.get(), s);
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/* Downgrade to a read lock. */
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debug(format("downgrading to read lock on '%1%'") % fnTempRoots);
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lockFile(state->fdTempRoots.get(), ltRead, true);
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}
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static std::string censored = "{censored}";
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void LocalStore::findTempRoots(FDs & fds, Roots & tempRoots, bool censor)
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void LocalStore::findTempRoots(Roots & tempRoots, bool censor)
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{
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/* Read the `temproots' directory for per-process temporary root
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files. */
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@ -174,35 +182,25 @@ void LocalStore::findTempRoots(FDs & fds, Roots & tempRoots, bool censor)
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pid_t pid = std::stoi(i.name);
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debug(format("reading temporary root file '%1%'") % path);
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FDPtr fd(new AutoCloseFD(open(path.c_str(), O_CLOEXEC | O_RDWR, 0666)));
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if (!*fd) {
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AutoCloseFD fd(open(path.c_str(), O_CLOEXEC | O_RDWR, 0666));
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if (!fd) {
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/* It's okay if the file has disappeared. */
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if (errno == ENOENT) continue;
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throw SysError("opening temporary roots file '%1%'", path);
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}
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/* This should work, but doesn't, for some reason. */
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//FDPtr fd(new AutoCloseFD(openLockFile(path, false)));
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//if (*fd == -1) continue;
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/* Try to acquire a write lock without blocking. This can
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only succeed if the owning process has died. In that case
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we don't care about its temporary roots. */
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if (lockFile(fd->get(), ltWrite, false)) {
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if (lockFile(fd.get(), ltWrite, false)) {
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printInfo("removing stale temporary roots file '%1%'", path);
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unlink(path.c_str());
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writeFull(fd->get(), "d");
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writeFull(fd.get(), "d");
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continue;
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}
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/* Acquire a read lock. This will prevent the owning process
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from upgrading to a write lock, therefore it will block in
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addTempRoot(). */
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debug(format("waiting for read lock on '%1%'") % path);
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lockFile(fd->get(), ltRead, true);
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/* Read the entire file. */
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string contents = readFile(fd->get());
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string contents = readFile(fd.get());
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/* Extract the roots. */
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string::size_type pos = 0, end;
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@ -213,8 +211,6 @@ void LocalStore::findTempRoots(FDs & fds, Roots & tempRoots, bool censor)
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tempRoots[parseStorePath(root)].emplace(censor ? censored : fmt("{temp:%d}", pid));
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pos = end + 1;
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}
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fds.push_back(fd); /* keep open */
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}
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}
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@ -299,8 +295,7 @@ Roots LocalStore::findRoots(bool censor)
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Roots roots;
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findRootsNoTemp(roots, censor);
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FDs fds;
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findTempRoots(fds, roots, censor);
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findTempRoots(roots, censor);
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return roots;
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}
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@ -455,160 +450,141 @@ struct LocalStore::GCState
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const GCOptions & options;
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GCResults & results;
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StorePathSet roots;
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StorePathSet tempRoots;
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StorePathSet dead;
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StorePathSet alive;
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bool gcKeepOutputs;
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bool gcKeepDerivations;
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bool shouldDelete;
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struct Shared
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{
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// The temp roots only store the hash part to make it easier to
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// ignore suffixes like '.lock', '.chroot' and '.check'.
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std::unordered_set<std::string> tempRoots;
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// Hash part of the store path currently being deleted, if
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// any.
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std::optional<std::string> pending;
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};
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Sync<Shared> shared;
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std::condition_variable wakeup;
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GCState(const GCOptions & options, GCResults & results)
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: options(options), results(results) { }
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};
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bool LocalStore::isActiveTempFile(const GCState & state,
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const Path & path, const string & suffix)
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{
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return hasSuffix(path, suffix)
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&& state.tempRoots.count(parseStorePath(string(path, 0, path.size() - suffix.size())));
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}
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void LocalStore::deleteGarbage(GCState & state, const Path & path)
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{
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uint64_t bytesFreed;
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deletePath(path, bytesFreed);
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state.results.bytesFreed += bytesFreed;
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}
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void LocalStore::deletePathRecursive(GCState & state, const Path & path)
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{
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checkInterrupt();
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auto storePath = maybeParseStorePath(path);
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if (storePath && isValidPath(*storePath)) {
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StorePathSet referrers;
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queryReferrers(*storePath, referrers);
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for (auto & i : referrers)
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if (printStorePath(i) != path) deletePathRecursive(state, printStorePath(i));
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invalidatePathChecked(*storePath);
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}
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Path realPath = realStoreDir + "/" + std::string(baseNameOf(path));
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struct stat st;
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if (lstat(realPath.c_str(), &st)) {
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if (errno == ENOENT) return;
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throw SysError("getting status of %1%", realPath);
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}
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printInfo(format("deleting '%1%'") % path);
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state.results.paths.insert(path);
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deleteGarbage(state, realPath);
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if (state.results.bytesFreed > state.options.maxFreed) {
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printInfo("deleted more than %d bytes; stopping", state.options.maxFreed);
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throw GCLimitReached();
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}
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}
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bool LocalStore::canReachRoot(GCState & state, StorePathSet & visited, const StorePath & path)
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{
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if (visited.count(path)) return false;
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if (state.alive.count(path)) return true;
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if (state.dead.count(path)) return false;
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if (state.roots.count(path)) {
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debug("cannot delete '%1%' because it's a root", printStorePath(path));
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state.alive.insert(path);
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return true;
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}
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visited.insert(path);
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if (!isValidPath(path)) return false;
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StorePathSet incoming;
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/* Don't delete this path if any of its referrers are alive. */
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queryReferrers(path, incoming);
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/* If keep-derivations is set and this is a derivation, then
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don't delete the derivation if any of the outputs are alive. */
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if (state.gcKeepDerivations && path.isDerivation()) {
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for (auto & [name, maybeOutPath] : queryPartialDerivationOutputMap(path))
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if (maybeOutPath &&
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isValidPath(*maybeOutPath) &&
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queryPathInfo(*maybeOutPath)->deriver == path
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)
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incoming.insert(*maybeOutPath);
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}
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/* If keep-outputs is set, then don't delete this path if there
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are derivers of this path that are not garbage. */
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if (state.gcKeepOutputs) {
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auto derivers = queryValidDerivers(path);
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for (auto & i : derivers)
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incoming.insert(i);
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}
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for (auto & i : incoming)
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if (i != path)
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if (canReachRoot(state, visited, i)) {
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state.alive.insert(path);
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return true;
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}
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return false;
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}
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void LocalStore::tryToDelete(GCState & state, const Path & path)
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bool LocalStore::tryToDelete(
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GCState & state,
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StorePathSet & visited,
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const Path & path,
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bool recursive)
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{
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checkInterrupt();
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auto realPath = realStoreDir + "/" + std::string(baseNameOf(path));
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if (realPath == linksDir) return;
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if (realPath == linksDir) return false;
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//Activity act(*logger, lvlDebug, format("considering whether to delete '%1%'") % path);
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auto storePath = maybeParseStorePath(path);
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if (!storePath || !isValidPath(*storePath)) {
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/* A lock file belonging to a path that we're building right
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now isn't garbage. */
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if (isActiveTempFile(state, path, ".lock")) return;
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/* Wake up any client waiting for deletion of this path to
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finish. */
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Finally releasePending([&]() {
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auto shared(state.shared.lock());
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shared->pending.reset();
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state.wakeup.notify_all();
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});
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/* Don't delete .chroot directories for derivations that are
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currently being built. */
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if (isActiveTempFile(state, path, ".chroot")) return;
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if (storePath) {
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/* Don't delete .check directories for derivations that are
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currently being built, because we may need to run
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diff-hook. */
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if (isActiveTempFile(state, path, ".check")) return;
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}
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if (!visited.insert(*storePath).second) return true;
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StorePathSet visited;
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if (state.alive.count(*storePath)) return false;
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if (state.dead.count(*storePath)) return true;
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if (state.roots.count(*storePath)) {
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debug("cannot delete '%s' because it's a root", path);
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state.alive.insert(*storePath);
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return false;
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}
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if (isValidPath(*storePath)) {
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StorePathSet incoming;
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/* Don't delete this path if any of its referrers are alive. */
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queryReferrers(*storePath, incoming);
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/* If keep-derivations is set and this is a derivation, then
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don't delete the derivation if any of the outputs are alive. */
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if (state.gcKeepDerivations && storePath->isDerivation()) {
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for (auto & [name, maybeOutPath] : queryPartialDerivationOutputMap(*storePath))
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if (maybeOutPath &&
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isValidPath(*maybeOutPath) &&
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queryPathInfo(*maybeOutPath)->deriver == *storePath)
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incoming.insert(*maybeOutPath);
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}
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/* If keep-outputs is set, then don't delete this path if there
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are derivers of this path that are not garbage. */
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if (state.gcKeepOutputs) {
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auto derivers = queryValidDerivers(*storePath);
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for (auto & i : derivers)
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incoming.insert(i);
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}
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for (auto & i : incoming)
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if (i != *storePath
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&& (recursive || state.options.pathsToDelete.count(i))
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&& !tryToDelete(state, visited, printStorePath(i), recursive))
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{
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state.alive.insert(*storePath);
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return false;
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}
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}
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{
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auto hashPart = std::string(storePath->hashPart());
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auto shared(state.shared.lock());
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if (shared->tempRoots.count(hashPart))
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return false;
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shared->pending = hashPart;
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}
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state.dead.insert(*storePath);
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if (storePath && canReachRoot(state, visited, *storePath)) {
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debug("cannot delete '%s' because it's still reachable", path);
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} else {
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/* No path we visited was a root, so everything is garbage.
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But we only delete ‘path’ and its referrers here so that
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‘nix-store --delete’ doesn't have the unexpected effect of
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recursing into derivations and outputs. */
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for (auto & i : visited)
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state.dead.insert(i);
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if (state.shouldDelete)
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deletePathRecursive(state, path);
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invalidatePathChecked(*storePath);
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}
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if (state.shouldDelete) {
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Path realPath = realStoreDir + "/" + std::string(baseNameOf(path));
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struct stat st;
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if (lstat(realPath.c_str(), &st)) {
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if (errno == ENOENT) return true;
|
||||
throw SysError("getting status of %1%", realPath);
|
||||
}
|
||||
|
||||
printInfo("deleting '%1%'", path);
|
||||
|
||||
state.results.paths.insert(path);
|
||||
|
||||
uint64_t bytesFreed;
|
||||
deletePath(realPath, bytesFreed);
|
||||
state.results.bytesFreed += bytesFreed;
|
||||
|
||||
if (state.results.bytesFreed > state.options.maxFreed) {
|
||||
printInfo("deleted more than %d bytes; stopping", state.options.maxFreed);
|
||||
throw GCLimitReached();
|
||||
}
|
||||
}
|
||||
|
||||
return true;
|
||||
}
|
||||
|
||||
|
||||
|
|
@ -678,7 +654,104 @@ void LocalStore::collectGarbage(const GCOptions & options, GCResults & results)
|
|||
deletePath(reservedPath);
|
||||
|
||||
/* Acquire the global GC root. */
|
||||
AutoCloseFD fdGCLock = openGCLock(ltWrite);
|
||||
FdLock gcLock(_state.lock()->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([&]() {
|
||||
std::map<int, std::pair<std::unique_ptr<AutoCloseFD>, std::string>> fdClients;
|
||||
bool quit = false;
|
||||
|
||||
while (!quit) {
|
||||
std::vector<struct pollfd> fds;
|
||||
fds.push_back({.fd = shutdownPipe.readSide.get(), .events = POLLIN});
|
||||
fds.push_back({.fd = fdServer.get(), .events = POLLIN});
|
||||
for (auto & i : fdClients)
|
||||
fds.push_back({.fd = i.first, .events = POLLIN});
|
||||
auto count = poll(fds.data(), fds.size(), -1);
|
||||
assert(count != -1);
|
||||
|
||||
for (auto & fd : fds) {
|
||||
if (!fd.revents) continue;
|
||||
if (fd.fd == shutdownPipe.readSide.get())
|
||||
/* Parent is asking us to quit. */
|
||||
quit = true;
|
||||
else if (fd.fd == fdServer.get()) {
|
||||
/* Accept a new connection. */
|
||||
assert(fd.revents & POLLIN);
|
||||
auto fdClient = std::make_unique<AutoCloseFD>(accept(fdServer.get(), nullptr, nullptr));
|
||||
if (*fdClient) {
|
||||
auto fd = fdClient->get();
|
||||
fdClients.insert({fd, std::make_pair(std::move(fdClient), "")});
|
||||
}
|
||||
}
|
||||
else {
|
||||
/* Receive data from a client. */
|
||||
auto fdClient = fdClients.find(fd.fd);
|
||||
assert(fdClient != fdClients.end());
|
||||
if (fd.revents & POLLIN) {
|
||||
char buf[16384];
|
||||
auto n = read(fd.fd, buf, sizeof(buf));
|
||||
if (n > 0) {
|
||||
fdClient->second.second.append(buf, n);
|
||||
/* Split the input into lines. */
|
||||
while (true) {
|
||||
auto p = fdClient->second.second.find('\n');
|
||||
if (p == std::string::npos) break;
|
||||
/* We got a full line. Send ack back
|
||||
to the client. */
|
||||
auto path = fdClient->second.second.substr(0, p);
|
||||
fdClient->second.second = fdClient->second.second.substr(p + 1);
|
||||
auto storePath = maybeParseStorePath(path);
|
||||
if (storePath) {
|
||||
debug("got new GC root '%s'", path);
|
||||
auto hashPart = std::string(storePath->hashPart());
|
||||
auto shared(state.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(state.wakeup);
|
||||
}
|
||||
} else
|
||||
printError("received garbage instead of a root from client");
|
||||
// This could block, but meh.
|
||||
try {
|
||||
writeFull(fd.fd, "1", false);
|
||||
} catch (SysError &) { }
|
||||
}
|
||||
} else if (n == 0)
|
||||
fdClients.erase(fdClient);
|
||||
} else
|
||||
fdClients.erase(fdClient);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
debug("GC roots server shut down");
|
||||
});
|
||||
|
||||
Finally stopServer([&]() {
|
||||
writeFull(shutdownPipe.writeSide.get(), "x", false);
|
||||
state.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. */
|
||||
|
|
@ -689,32 +762,26 @@ void LocalStore::collectGarbage(const GCOptions & options, GCResults & results)
|
|||
|
||||
for (auto & i : rootMap) state.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.shared.lock()->tempRoots.insert(std::string(root.first.hashPart()));
|
||||
state.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. */
|
||||
|
||||
/* Now 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())
|
||||
StorePathSet visited;
|
||||
if (!tryToDelete(state, visited, printStorePath(i), false))
|
||||
throw Error(
|
||||
"cannot delete path '%1%' since it is still alive. "
|
||||
"To find out why use: "
|
||||
"To find out why, use: "
|
||||
"nix-store --query --roots",
|
||||
printStorePath(i));
|
||||
}
|
||||
|
|
@ -727,44 +794,21 @@ void LocalStore::collectGarbage(const GCOptions & options, GCResults & results)
|
|||
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. */
|
||||
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);
|
||||
else
|
||||
tryToDelete(state, path);
|
||||
StorePathSet visited;
|
||||
tryToDelete(state, visited, storeDir + "/" + name, true);
|
||||
}
|
||||
|
||||
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<Path> 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) {
|
||||
}
|
||||
}
|
||||
|
|
|
|||
|
|
@ -382,6 +382,11 @@ LocalStore::LocalStore(const Params & params)
|
|||
(select id from Realisations where drvPath = ? and outputName = ?));
|
||||
)");
|
||||
}
|
||||
|
||||
Path fnGCLock = stateDir + "/gc.lock";
|
||||
state->fdGCLock = open(fnGCLock.c_str(), O_RDWR | O_CREAT | O_CLOEXEC, 0600);
|
||||
if (!state->fdGCLock)
|
||||
throw SysError("opening global GC lock '%1%'", fnGCLock);
|
||||
}
|
||||
|
||||
|
||||
|
|
@ -1504,7 +1509,7 @@ 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);
|
||||
FdLock gcLock(_state.lock()->fdGCLock.get(), ltWrite, true, "waiting for the big garbage collector lock...");
|
||||
|
||||
StringSet store;
|
||||
for (auto & i : readDirectory(realStoreDir)) store.insert(i.name);
|
||||
|
|
@ -1515,8 +1520,6 @@ 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);
|
||||
|
||||
|
|
|
|||
|
|
@ -58,9 +58,15 @@ private:
|
|||
struct Stmts;
|
||||
std::unique_ptr<Stmts> 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<std::chrono::steady_clock> lastGCCheck;
|
||||
|
|
@ -150,10 +156,7 @@ public:
|
|||
|
||||
private:
|
||||
|
||||
typedef std::shared_ptr<AutoCloseFD> FDPtr;
|
||||
typedef list<FDPtr> FDs;
|
||||
|
||||
void findTempRoots(FDs & fds, Roots & roots, bool censor);
|
||||
void findTempRoots(Roots & roots, bool censor);
|
||||
|
||||
public:
|
||||
|
||||
|
|
@ -235,18 +238,11 @@ private:
|
|||
|
||||
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);
|
||||
bool tryToDelete(
|
||||
GCState & state,
|
||||
StorePathSet & visited,
|
||||
const Path & path,
|
||||
bool recursive);
|
||||
|
||||
void findRoots(const Path & path, unsigned char type, Roots & roots);
|
||||
|
||||
|
|
|
|||
|
|
@ -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);
|
||||
}
|
||||
|
||||
|
||||
}
|
||||
|
|
|
|||
|
|
@ -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);
|
||||
}
|
||||
};
|
||||
|
||||
}
|
||||
|
|
|
|||
|
|
@ -56,14 +56,7 @@ ref<RemoteStore::Connection> UDSRemoteStore::openConnection()
|
|||
auto conn = make_ref<Connection>();
|
||||
|
||||
/* 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);
|
||||
|
||||
|
|
|
|||
|
|
@ -1670,7 +1670,7 @@ std::unique_ptr<InterruptCallback> createInterruptCallback(std::function<void()>
|
|||
}
|
||||
|
||||
|
||||
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);
|
||||
|
||||
|
|
|
|||
|
|
@ -571,6 +571,9 @@ 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);
|
||||
|
||||
|
|
|
|||
|
|
@ -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
|
||||
|
|
|
|||
|
|
@ -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)
|
||||
|
||||
|
|
|
|||
Loading…
Reference in a new issue