From 4202a3bc4e7ce687be245539f6d796226f7d9e37 Mon Sep 17 00:00:00 2001 From: Eelco Dolstra Date: Fri, 18 Jun 2021 17:04:11 +0200 Subject: [PATCH] UDSRemoteStore: Support the 'root' store parameter Useful when we're using a daemon with a chroot store, e.g. $ NIX_DAEMON_SOCKET_PATH=/tmp/chroot/nix/var/nix/daemon-socket/socket nix-daemon --store /tmp/chroot Then the client can now connect with $ nix build --store unix:///tmp/chroot/nix/var/nix/daemon-socket/socket?root=/tmp/chroot nixpkgs#hello --- src/libstore/build/local-derivation-goal.cc | 4 ++-- src/libstore/gc.cc | 4 ++-- src/libstore/local-fs-store.hh | 5 ++++- src/libstore/local-store.cc | 13 +++++-------- src/libstore/local-store.hh | 5 ----- src/libstore/optimise-store.cc | 2 +- src/nix/run.cc | 4 ++-- 7 files changed, 16 insertions(+), 21 deletions(-) diff --git a/src/libstore/build/local-derivation-goal.cc b/src/libstore/build/local-derivation-goal.cc index 28981a1a1..73e2350ea 100644 --- a/src/libstore/build/local-derivation-goal.cc +++ b/src/libstore/build/local-derivation-goal.cc @@ -292,7 +292,7 @@ bool LocalDerivationGoal::cleanupDecideWhetherDiskFull() auto & localStore = getLocalStore(); uint64_t required = 8ULL * 1024 * 1024; // FIXME: make configurable struct statvfs st; - if (statvfs(localStore.realStoreDir.c_str(), &st) == 0 && + if (statvfs(localStore.realStoreDir.get().c_str(), &st) == 0 && (uint64_t) st.f_bavail * st.f_bsize < required) diskFull = true; if (statvfs(tmpDir.c_str(), &st) == 0 && @@ -417,7 +417,7 @@ void LocalDerivationGoal::startBuilder() } auto & localStore = getLocalStore(); - if (localStore.storeDir != localStore.realStoreDir) { + if (localStore.storeDir != localStore.realStoreDir.get()) { #if __linux__ useChroot = true; #else diff --git a/src/libstore/gc.cc b/src/libstore/gc.cc index bc692ca42..5a62c6529 100644 --- a/src/libstore/gc.cc +++ b/src/libstore/gc.cc @@ -775,7 +775,7 @@ void LocalStore::collectGarbage(const GCOptions & options, GCResults & results) try { - AutoCloseDir dir(opendir(realStoreDir.c_str())); + AutoCloseDir dir(opendir(realStoreDir.get().c_str())); if (!dir) throw SysError("opening directory '%1%'", realStoreDir); /* Read the store and immediately delete all paths that @@ -856,7 +856,7 @@ void LocalStore::autoGC(bool sync) return std::stoll(readFile(*fakeFreeSpaceFile)); struct statvfs st; - if (statvfs(realStoreDir.c_str(), &st)) + if (statvfs(realStoreDir.get().c_str(), &st)) throw SysError("getting filesystem info about '%s'", realStoreDir); return (uint64_t) st.f_bavail * st.f_frsize; diff --git a/src/libstore/local-fs-store.hh b/src/libstore/local-fs-store.hh index 55941b771..f8b19d00d 100644 --- a/src/libstore/local-fs-store.hh +++ b/src/libstore/local-fs-store.hh @@ -18,6 +18,9 @@ struct LocalFSStoreConfig : virtual StoreConfig const PathSetting logDir{(StoreConfig*) this, false, rootDir != "" ? rootDir + "/nix/var/log/nix" : settings.nixLogDir, "log", "directory where Nix will store state"}; + const PathSetting realStoreDir{(StoreConfig*) this, false, + rootDir != "" ? rootDir + "/nix/store" : storeDir, "real", + "physical path to the Nix store"}; }; class LocalFSStore : public virtual LocalFSStoreConfig, public virtual Store @@ -34,7 +37,7 @@ public: /* Register a permanent GC root. */ Path addPermRoot(const StorePath & storePath, const Path & gcRoot); - virtual Path getRealStoreDir() { return storeDir; } + virtual Path getRealStoreDir() { return realStoreDir; } Path toRealPath(const Path & storePath) override { diff --git a/src/libstore/local-store.cc b/src/libstore/local-store.cc index efea7bd23..28c175a51 100644 --- a/src/libstore/local-store.cc +++ b/src/libstore/local-store.cc @@ -106,9 +106,6 @@ LocalStore::LocalStore(const Params & params) , LocalStoreConfig(params) , Store(params) , LocalFSStore(params) - , realStoreDir_{this, false, rootDir != "" ? rootDir + "/nix/store" : storeDir, "real", - "physical path to the Nix store"} - , realStoreDir(realStoreDir_) , dbDir(stateDir + "/db") , linksDir(realStoreDir + "/.links") , reservedPath(dbDir + "/reserved") @@ -153,13 +150,13 @@ LocalStore::LocalStore(const Params & params) printError("warning: the group '%1%' specified in 'build-users-group' does not exist", settings.buildUsersGroup); else { struct stat st; - if (stat(realStoreDir.c_str(), &st)) + if (stat(realStoreDir.get().c_str(), &st)) throw SysError("getting attributes of path '%1%'", realStoreDir); if (st.st_uid != 0 || st.st_gid != gr->gr_gid || (st.st_mode & ~S_IFMT) != perm) { - if (chown(realStoreDir.c_str(), 0, gr->gr_gid) == -1) + if (chown(realStoreDir.get().c_str(), 0, gr->gr_gid) == -1) throw SysError("changing ownership of path '%1%'", realStoreDir); - if (chmod(realStoreDir.c_str(), perm) == -1) + if (chmod(realStoreDir.get().c_str(), perm) == -1) throw SysError("changing permissions on path '%1%'", realStoreDir); } } @@ -437,14 +434,14 @@ void LocalStore::makeStoreWritable() if (getuid() != 0) return; /* Check if /nix/store is on a read-only mount. */ struct statvfs stat; - if (statvfs(realStoreDir.c_str(), &stat) != 0) + if (statvfs(realStoreDir.get().c_str(), &stat) != 0) throw SysError("getting info about the Nix store mount point"); if (stat.f_flag & ST_RDONLY) { if (unshare(CLONE_NEWNS) == -1) throw SysError("setting up a private mount namespace"); - if (mount(0, realStoreDir.c_str(), "none", MS_REMOUNT | MS_BIND, 0) == -1) + if (mount(0, realStoreDir.get().c_str(), "none", MS_REMOUNT | MS_BIND, 0) == -1) throw SysError("remounting %1% writable", realStoreDir); } #endif diff --git a/src/libstore/local-store.hh b/src/libstore/local-store.hh index c0b8e0da6..15c7fc306 100644 --- a/src/libstore/local-store.hh +++ b/src/libstore/local-store.hh @@ -83,9 +83,6 @@ private: public: - PathSetting realStoreDir_; - - const Path realStoreDir; const Path dbDir; const Path linksDir; const Path reservedPath; @@ -279,8 +276,6 @@ private: void signPathInfo(ValidPathInfo & info); void signRealisation(Realisation &); - Path getRealStoreDir() override { return realStoreDir; } - void createUser(const std::string & userName, uid_t userId) override; // XXX: Make a generic `Store` method diff --git a/src/libstore/optimise-store.cc b/src/libstore/optimise-store.cc index 78d587139..d95e54af1 100644 --- a/src/libstore/optimise-store.cc +++ b/src/libstore/optimise-store.cc @@ -198,7 +198,7 @@ void LocalStore::optimisePath_(Activity * act, OptimiseStats & stats, /* Make the containing directory writable, but only if it's not the store itself (we don't want or need to mess with its permissions). */ - bool mustToggle = dirOf(path) != realStoreDir; + bool mustToggle = dirOf(path) != realStoreDir.get(); if (mustToggle) makeWritable(dirOf(path)); /* When we're done, make the directory read-only again and reset diff --git a/src/nix/run.cc b/src/nix/run.cc index f684c5ea4..c0ba05a3e 100644 --- a/src/nix/run.cc +++ b/src/nix/run.cc @@ -43,8 +43,8 @@ struct RunCommon : virtual Command helper program (chrootHelper() below) to do the work. */ auto store2 = store.dynamic_pointer_cast(); - if (store2 && store->storeDir != store2->realStoreDir) { - Strings helperArgs = { chrootHelperName, store->storeDir, store2->realStoreDir, program }; + if (store2 && store->storeDir != store2->getRealStoreDir()) { + Strings helperArgs = { chrootHelperName, store->storeDir, store2->getRealStoreDir(), program }; for (auto & arg : args) helperArgs.push_back(arg); execv(readLink("/proc/self/exe").c_str(), stringsToCharPtrs(helperArgs).data());