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-rw-r--r--src/libstore/local-store.cc1037
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diff --git a/src/libstore/local-store.cc b/src/libstore/local-store.cc
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+++ b/src/libstore/local-store.cc
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+#include "local-store.hh"
+#include "util.hh"
+#include "globals.hh"
+#include "db.hh"
+#include "archive.hh"
+#include "pathlocks.hh"
+#include "gc.hh"
+#include "aterm.hh"
+#include "derivations-ast.hh"
+
+#include <iostream>
+#include <algorithm>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <utime.h>
+
+namespace nix {
+
+
+/* Nix database. */
+static Database nixDB;
+
+
+/* Database tables. */
+
+/* dbValidPaths :: Path -> ()
+
+ The existence of a key $p$ indicates that path $p$ is valid (that
+ is, produced by a succesful build). */
+static TableId dbValidPaths = 0;
+
+/* dbReferences :: Path -> [Path]
+
+ This table lists the outgoing file system references for each
+ output path that has been built by a Nix derivation. These are
+ found by scanning the path for the hash components of input
+ paths. */
+static TableId dbReferences = 0;
+
+/* dbReferrers :: Path -> Path
+
+ This table is just the reverse mapping of dbReferences. This table
+ can have duplicate keys, each corresponding value denoting a single
+ referrer. */
+static TableId dbReferrers = 0;
+
+/* dbSubstitutes :: Path -> [[Path]]
+
+ Each pair $(p, subs)$ tells Nix that it can use any of the
+ substitutes in $subs$ to build path $p$. Each substitute defines a
+ command-line invocation of a program (i.e., the first list element
+ is the full path to the program, the remaining elements are
+ arguments).
+
+ The main purpose of this is for distributed caching of derivates.
+ One system can compute a derivate and put it on a website (as a Nix
+ archive), for instance, and then another system can register a
+ substitute for that derivate. The substitute in this case might be
+ a Nix derivation that fetches the Nix archive.
+*/
+static TableId dbSubstitutes = 0;
+
+/* dbDerivers :: Path -> [Path]
+
+ This table lists the derivation used to build a path. There can
+ only be multiple such paths for fixed-output derivations (i.e.,
+ derivations specifying an expected hash). */
+static TableId dbDerivers = 0;
+
+
+bool Substitute::operator == (const Substitute & sub) const
+{
+ return program == sub.program
+ && args == sub.args;
+}
+
+
+static void upgradeStore07();
+static void upgradeStore09();
+
+
+void checkStoreNotSymlink()
+{
+ if (getEnv("NIX_IGNORE_SYMLINK_STORE") == "1") return;
+ Path path = nixStore;
+ struct stat st;
+ while (path != "/") {
+ if (lstat(path.c_str(), &st))
+ throw SysError(format("getting status of `%1%'") % path);
+ if (S_ISLNK(st.st_mode))
+ throw Error(format(
+ "the path `%1%' is a symlink; "
+ "this is not allowed for the Nix store and its parent directories")
+ % path);
+ path = dirOf(path);
+ }
+}
+
+
+LocalStore::LocalStore(bool reserveSpace)
+{
+ if (readOnlyMode) return;
+
+ checkStoreNotSymlink();
+
+ try {
+ Path reservedPath = nixDBPath + "/reserved";
+ string s = querySetting("gc-reserved-space", "");
+ int reservedSize;
+ if (!string2Int(s, reservedSize)) reservedSize = 1024 * 1024;
+ if (reserveSpace) {
+ struct stat st;
+ if (stat(reservedPath.c_str(), &st) == -1 ||
+ st.st_size != reservedSize)
+ writeFile(reservedPath, string(reservedSize, 'X'));
+ }
+ else
+ deletePath(reservedPath);
+ } catch (SysError & e) { /* don't care about errors */
+ }
+
+ try {
+ nixDB.open(nixDBPath);
+ } catch (DbNoPermission & e) {
+ printMsg(lvlTalkative, "cannot access Nix database; continuing anyway");
+ readOnlyMode = true;
+ return;
+ }
+ dbValidPaths = nixDB.openTable("validpaths");
+ dbReferences = nixDB.openTable("references");
+ dbReferrers = nixDB.openTable("referrers", true); /* must be sorted */
+ dbSubstitutes = nixDB.openTable("substitutes");
+ dbDerivers = nixDB.openTable("derivers");
+
+ int curSchema = 0;
+ Path schemaFN = nixDBPath + "/schema";
+ if (pathExists(schemaFN)) {
+ string s = readFile(schemaFN);
+ if (!string2Int(s, curSchema))
+ throw Error(format("`%1%' is corrupt") % schemaFN);
+ }
+
+ if (curSchema > nixSchemaVersion)
+ throw Error(format("current Nix store schema is version %1%, but I only support %2%")
+ % curSchema % nixSchemaVersion);
+
+ if (curSchema < nixSchemaVersion) {
+ if (curSchema <= 1)
+ upgradeStore07();
+ if (curSchema == 2)
+ upgradeStore09();
+ writeFile(schemaFN, (format("%1%") % nixSchemaVersion).str());
+ }
+}
+
+
+LocalStore::~LocalStore()
+{
+ /* If the database isn't open, this is a NOP. */
+ nixDB.close();
+}
+
+
+void createStoreTransaction(Transaction & txn)
+{
+ Transaction txn2(nixDB);
+ txn2.moveTo(txn);
+}
+
+
+/* Path copying. */
+
+struct CopySink : DumpSink
+{
+ string s;
+ virtual void operator () (const unsigned char * data, unsigned int len)
+ {
+ s.append((const char *) data, len);
+ }
+};
+
+
+struct CopySource : RestoreSource
+{
+ string & s;
+ unsigned int pos;
+ CopySource(string & _s) : s(_s), pos(0) { }
+ virtual void operator () (unsigned char * data, unsigned int len)
+ {
+ s.copy((char *) data, len, pos);
+ pos += len;
+ assert(pos <= s.size());
+ }
+};
+
+
+void copyPath(const Path & src, const Path & dst)
+{
+ debug(format("copying `%1%' to `%2%'") % src % dst);
+
+ /* Dump an archive of the path `src' into a string buffer, then
+ restore the archive to `dst'. This is not a very good method
+ for very large paths, but `copyPath' is mainly used for small
+ files. */
+
+ CopySink sink;
+ {
+ SwitchToOriginalUser sw;
+ dumpPath(src, sink);
+ }
+
+ CopySource source(sink.s);
+ restorePath(dst, source);
+}
+
+
+void canonicalisePathMetaData(const Path & path)
+{
+ checkInterrupt();
+
+ struct stat st;
+ if (lstat(path.c_str(), &st))
+ throw SysError(format("getting attributes of path `%1%'") % path);
+
+ if (!S_ISLNK(st.st_mode)) {
+
+ /* Mask out all type related bits. */
+ mode_t mode = st.st_mode & ~S_IFMT;
+
+ if (mode != 0444 && mode != 0555) {
+ mode = (st.st_mode & S_IFMT)
+ | 0444
+ | (st.st_mode & S_IXUSR ? 0111 : 0);
+ if (chmod(path.c_str(), mode) == -1)
+ throw SysError(format("changing mode of `%1%' to %2$o") % path % mode);
+ }
+
+ if (st.st_uid != getuid() || st.st_gid != getgid()) {
+ if (chown(path.c_str(), getuid(), getgid()) == -1)
+ throw SysError(format("changing owner/group of `%1%' to %2%/%3%")
+ % path % getuid() % getgid());
+ }
+
+ if (st.st_mtime != 0) {
+ struct utimbuf utimbuf;
+ utimbuf.actime = st.st_atime;
+ utimbuf.modtime = 0;
+ if (utime(path.c_str(), &utimbuf) == -1)
+ throw SysError(format("changing modification time of `%1%'") % path);
+ }
+
+ }
+
+ if (S_ISDIR(st.st_mode)) {
+ Strings names = readDirectory(path);
+ for (Strings::iterator i = names.begin(); i != names.end(); ++i)
+ canonicalisePathMetaData(path + "/" + *i);
+ }
+}
+
+
+bool isValidPathTxn(const Transaction & txn, const Path & path)
+{
+ string s;
+ return nixDB.queryString(txn, dbValidPaths, path, s);
+}
+
+
+bool LocalStore::isValidPath(const Path & path)
+{
+ return isValidPathTxn(noTxn, path);
+}
+
+
+static Substitutes readSubstitutes(const Transaction & txn,
+ const Path & srcPath);
+
+
+static bool isRealisablePath(const Transaction & txn, const Path & path)
+{
+ return isValidPathTxn(txn, path)
+ || readSubstitutes(txn, path).size() > 0;
+}
+
+
+static string addPrefix(const string & prefix, const string & s)
+{
+ return prefix + string(1, (char) 0) + s;
+}
+
+
+static string stripPrefix(const string & prefix, const string & s)
+{
+ if (s.size() <= prefix.size() ||
+ string(s, 0, prefix.size()) != prefix ||
+ s[prefix.size()] != 0)
+ throw Error(format("string `%1%' is missing prefix `%2%'")
+ % s % prefix);
+ return string(s, prefix.size() + 1);
+}
+
+
+static PathSet getReferrers(const Transaction & txn, const Path & storePath)
+{
+ PathSet referrers;
+ Strings keys;
+ nixDB.enumTable(txn, dbReferrers, keys, storePath + string(1, (char) 0));
+ for (Strings::iterator i = keys.begin(); i != keys.end(); ++i)
+ referrers.insert(stripPrefix(storePath, *i));
+ return referrers;
+}
+
+
+void setReferences(const Transaction & txn, const Path & storePath,
+ const PathSet & references)
+{
+ /* For unrealisable paths, we can only clear the references. */
+ if (references.size() > 0 && !isRealisablePath(txn, storePath))
+ throw Error(
+ format("cannot set references for path `%1%' which is invalid and has no substitutes")
+ % storePath);
+
+ Paths oldReferences;
+ nixDB.queryStrings(txn, dbReferences, storePath, oldReferences);
+
+ PathSet oldReferences2(oldReferences.begin(), oldReferences.end());
+ if (oldReferences2 == references) return;
+
+ nixDB.setStrings(txn, dbReferences, storePath,
+ Paths(references.begin(), references.end()));
+
+ /* Update the referrers mappings of all new referenced paths. */
+ for (PathSet::const_iterator i = references.begin();
+ i != references.end(); ++i)
+ if (oldReferences2.find(*i) == oldReferences2.end())
+ nixDB.setString(txn, dbReferrers, addPrefix(*i, storePath), "");
+
+ /* Remove referrer mappings from paths that are no longer
+ references. */
+ for (Paths::iterator i = oldReferences.begin();
+ i != oldReferences.end(); ++i)
+ if (references.find(*i) == references.end())
+ nixDB.delPair(txn, dbReferrers, addPrefix(*i, storePath));
+}
+
+
+void queryReferences(const Transaction & txn,
+ const Path & storePath, PathSet & references)
+{
+ Paths references2;
+ if (!isRealisablePath(txn, storePath))
+ throw Error(format("path `%1%' is not valid") % storePath);
+ nixDB.queryStrings(txn, dbReferences, storePath, references2);
+ references.insert(references2.begin(), references2.end());
+}
+
+
+void LocalStore::queryReferences(const Path & storePath,
+ PathSet & references)
+{
+ nix::queryReferences(noTxn, storePath, references);
+}
+
+
+void queryReferrers(const Transaction & txn,
+ const Path & storePath, PathSet & referrers)
+{
+ if (!isRealisablePath(txn, storePath))
+ throw Error(format("path `%1%' is not valid") % storePath);
+ PathSet referrers2 = getReferrers(txn, storePath);
+ referrers.insert(referrers2.begin(), referrers2.end());
+}
+
+
+void LocalStore::queryReferrers(const Path & storePath,
+ PathSet & referrers)
+{
+ nix::queryReferrers(noTxn, storePath, referrers);
+}
+
+
+void setDeriver(const Transaction & txn, const Path & storePath,
+ const Path & deriver)
+{
+ assertStorePath(storePath);
+ if (deriver == "") return;
+ assertStorePath(deriver);
+ if (!isRealisablePath(txn, storePath))
+ throw Error(format("path `%1%' is not valid") % storePath);
+ nixDB.setString(txn, dbDerivers, storePath, deriver);
+}
+
+
+Path queryDeriver(const Transaction & txn, const Path & storePath)
+{
+ if (!isRealisablePath(txn, storePath))
+ throw Error(format("path `%1%' is not valid") % storePath);
+ Path deriver;
+ if (nixDB.queryString(txn, dbDerivers, storePath, deriver))
+ return deriver;
+ else
+ return "";
+}
+
+
+const int substituteVersion = 2;
+
+
+static Substitutes readSubstitutes(const Transaction & txn,
+ const Path & srcPath)
+{
+ Strings ss;
+ nixDB.queryStrings(txn, dbSubstitutes, srcPath, ss);
+
+ Substitutes subs;
+
+ for (Strings::iterator i = ss.begin(); i != ss.end(); ++i) {
+ if (i->size() < 4 || (*i)[3] != 0) {
+ /* Old-style substitute. !!! remove this code
+ eventually? */
+ break;
+ }
+ Strings ss2 = unpackStrings(*i);
+ if (ss2.size() == 0) continue;
+ int version;
+ if (!string2Int(ss2.front(), version)) continue;
+ if (version != substituteVersion) continue;
+ if (ss2.size() != 4) throw Error("malformed substitute");
+ Strings::iterator j = ss2.begin();
+ j++;
+ Substitute sub;
+ sub.deriver = *j++;
+ sub.program = *j++;
+ sub.args = unpackStrings(*j++);
+ subs.push_back(sub);
+ }
+
+ return subs;
+}
+
+
+static void writeSubstitutes(const Transaction & txn,
+ const Path & srcPath, const Substitutes & subs)
+{
+ Strings ss;
+
+ for (Substitutes::const_iterator i = subs.begin();
+ i != subs.end(); ++i)
+ {
+ Strings ss2;
+ ss2.push_back((format("%1%") % substituteVersion).str());
+ ss2.push_back(i->deriver);
+ ss2.push_back(i->program);
+ ss2.push_back(packStrings(i->args));
+ ss.push_back(packStrings(ss2));
+ }
+
+ nixDB.setStrings(txn, dbSubstitutes, srcPath, ss);
+}
+
+
+void registerSubstitute(const Transaction & txn,
+ const Path & srcPath, const Substitute & sub)
+{
+ assertStorePath(srcPath);
+
+ Substitutes subs = readSubstitutes(txn, srcPath);
+
+ if (find(subs.begin(), subs.end(), sub) != subs.end())
+ return;
+
+ /* New substitutes take precedence over old ones. If the
+ substitute is already present, it's moved to the front. */
+ remove(subs.begin(), subs.end(), sub);
+ subs.push_front(sub);
+
+ writeSubstitutes(txn, srcPath, subs);
+}
+
+
+Substitutes querySubstitutes(const Transaction & txn, const Path & srcPath)
+{
+ return readSubstitutes(txn, srcPath);
+}
+
+
+Substitutes LocalStore::querySubstitutes(const Path & srcPath)
+{
+ return nix::querySubstitutes(noTxn, srcPath);
+}
+
+
+static void invalidatePath(Transaction & txn, const Path & path);
+
+
+void clearSubstitutes()
+{
+ Transaction txn(nixDB);
+
+ /* Iterate over all paths for which there are substitutes. */
+ Paths subKeys;
+ nixDB.enumTable(txn, dbSubstitutes, subKeys);
+ for (Paths::iterator i = subKeys.begin(); i != subKeys.end(); ++i) {
+
+ /* Delete all substitutes for path *i. */
+ nixDB.delPair(txn, dbSubstitutes, *i);
+
+ /* Maintain the cleanup invariant. */
+ if (!isValidPathTxn(txn, *i))
+ invalidatePath(txn, *i);
+ }
+
+ /* !!! there should be no referrers to any of the invalid
+ substitutable paths. This should be the case by construction
+ (the only referrers can be other invalid substitutable paths,
+ which have all been removed now). */
+
+ txn.commit();
+}
+
+
+static void setHash(const Transaction & txn, const Path & storePath,
+ const Hash & hash)
+{
+ assert(hash.type == htSHA256);
+ nixDB.setString(txn, dbValidPaths, storePath, "sha256:" + printHash(hash));
+}
+
+
+static Hash queryHash(const Transaction & txn, const Path & storePath)
+{
+ string s;
+ nixDB.queryString(txn, dbValidPaths, storePath, s);
+ string::size_type colon = s.find(':');
+ if (colon == string::npos)
+ throw Error(format("corrupt hash `%1%' in valid-path entry for `%2%'")
+ % s % storePath);
+ HashType ht = parseHashType(string(s, 0, colon));
+ if (ht == htUnknown)
+ throw Error(format("unknown hash type `%1%' in valid-path entry for `%2%'")
+ % string(s, 0, colon) % storePath);
+ return parseHash(ht, string(s, colon + 1));
+}
+
+
+Hash LocalStore::queryPathHash(const Path & path)
+{
+ if (!isValidPath(path))
+ throw Error(format("path `%1%' is not valid") % path);
+ return queryHash(noTxn, path);
+}
+
+
+void registerValidPath(const Transaction & txn,
+ const Path & path, const Hash & hash, const PathSet & references,
+ const Path & deriver)
+{
+ ValidPathInfo info;
+ info.path = path;
+ info.hash = hash;
+ info.references = references;
+ info.deriver = deriver;
+ ValidPathInfos infos;
+ infos.push_back(info);
+ registerValidPaths(txn, infos);
+}
+
+
+void registerValidPaths(const Transaction & txn,
+ const ValidPathInfos & infos)
+{
+ PathSet newPaths;
+ for (ValidPathInfos::const_iterator i = infos.begin();
+ i != infos.end(); ++i)
+ newPaths.insert(i->path);
+
+ for (ValidPathInfos::const_iterator i = infos.begin();
+ i != infos.end(); ++i)
+ {
+ assertStorePath(i->path);
+
+ debug(format("registering path `%1%'") % i->path);
+ setHash(txn, i->path, i->hash);
+
+ setReferences(txn, i->path, i->references);
+
+ /* Check that all referenced paths are also valid (or about to
+ become valid). */
+ for (PathSet::iterator j = i->references.begin();
+ j != i->references.end(); ++j)
+ if (!isValidPathTxn(txn, *j) && newPaths.find(*j) == newPaths.end())
+ throw Error(format("cannot register path `%1%' as valid, since its reference `%2%' is invalid")
+ % i->path % *j);
+
+ setDeriver(txn, i->path, i->deriver);
+ }
+}
+
+
+/* Invalidate a path. The caller is responsible for checking that
+ there are no referrers. */
+static void invalidatePath(Transaction & txn, const Path & path)
+{
+ debug(format("unregistering path `%1%'") % path);
+
+ /* Clear the `references' entry for this path, as well as the
+ inverse `referrers' entries, and the `derivers' entry; but only
+ if there are no substitutes for this path. This maintains the
+ cleanup invariant. */
+ if (querySubstitutes(txn, path).size() == 0) {
+ setReferences(txn, path, PathSet());
+ nixDB.delPair(txn, dbDerivers, path);
+ }
+
+ nixDB.delPair(txn, dbValidPaths, path);
+}
+
+
+Path LocalStore::_addToStore(bool fixed, bool recursive,
+ string hashAlgo, const Path & _srcPath)
+{
+ Path srcPath(absPath(_srcPath));
+ debug(format("adding `%1%' to the store") % srcPath);
+
+ Hash h(htSHA256);
+ {
+ SwitchToOriginalUser sw;
+ h = hashPath(htSHA256, srcPath);
+ }
+
+ string baseName = baseNameOf(srcPath);
+
+ Path dstPath;
+
+ if (fixed) {
+
+ HashType ht(parseHashType(hashAlgo));
+ Hash h2(ht);
+ {
+ SwitchToOriginalUser sw;
+ h2 = recursive ? hashPath(ht, srcPath) : hashFile(ht, srcPath);
+ }
+
+ dstPath = makeFixedOutputPath(recursive, hashAlgo, h2, baseName);
+ }
+
+ else dstPath = makeStorePath("source", h, baseName);
+
+ if (!readOnlyMode) addTempRoot(dstPath);
+
+ if (!readOnlyMode && !isValidPath(dstPath)) {
+
+ /* The first check above is an optimisation to prevent
+ unnecessary lock acquisition. */
+
+ PathLocks outputLock(singleton<PathSet, Path>(dstPath));
+
+ if (!isValidPath(dstPath)) {
+
+ if (pathExists(dstPath)) deletePath(dstPath);
+
+ copyPath(srcPath, dstPath);
+
+ Hash h2 = hashPath(htSHA256, dstPath);
+ if (h != h2)
+ throw Error(format("contents of `%1%' changed while copying it to `%2%' (%3% -> %4%)")
+ % srcPath % dstPath % printHash(h) % printHash(h2));
+
+ canonicalisePathMetaData(dstPath);
+
+ Transaction txn(nixDB);
+ registerValidPath(txn, dstPath, h, PathSet(), "");
+ txn.commit();
+ }
+
+ outputLock.setDeletion(true);
+ }
+
+ return dstPath;
+}
+
+
+Path LocalStore::addToStore(const Path & srcPath)
+{
+ return _addToStore(false, false, "", srcPath);
+}
+
+
+Path LocalStore::addToStoreFixed(bool recursive, string hashAlgo, const Path & srcPath)
+{
+ return _addToStore(true, recursive, hashAlgo, srcPath);
+}
+
+
+Path LocalStore::addTextToStore(const string & suffix, const string & s,
+ const PathSet & references)
+{
+ Hash hash = hashString(htSHA256, s);
+
+ Path dstPath = makeStorePath("text", hash, suffix);
+
+ if (!readOnlyMode) addTempRoot(dstPath);
+
+ if (!readOnlyMode && !isValidPath(dstPath)) {
+
+ PathLocks outputLock(singleton<PathSet, Path>(dstPath));
+
+ if (!isValidPath(dstPath)) {
+
+ if (pathExists(dstPath)) deletePath(dstPath);
+
+ writeStringToFile(dstPath, s);
+
+ canonicalisePathMetaData(dstPath);
+
+ Transaction txn(nixDB);
+ registerValidPath(txn, dstPath,
+ hashPath(htSHA256, dstPath), references, "");
+ txn.commit();
+ }
+
+ outputLock.setDeletion(true);
+ }
+
+ return dstPath;
+}
+
+
+void deleteFromStore(const Path & _path, unsigned long long & bytesFreed)
+{
+ bytesFreed = 0;
+ Path path(canonPath(_path));
+
+ assertStorePath(path);
+
+ Transaction txn(nixDB);
+ if (isValidPathTxn(txn, path)) {
+ PathSet referrers = getReferrers(txn, path);
+ for (PathSet::iterator i = referrers.begin();
+ i != referrers.end(); ++i)
+ if (*i != path && isValidPathTxn(txn, *i))
+ throw Error(format("cannot delete path `%1%' because it is in use by path `%2%'") % path % *i);
+ invalidatePath(txn, path);
+ }
+ txn.commit();
+
+ deletePath(path, bytesFreed);
+}
+
+
+void verifyStore(bool checkContents)
+{
+ Transaction txn(nixDB);
+
+ Paths paths;
+ PathSet validPaths;
+ nixDB.enumTable(txn, dbValidPaths, paths);
+
+ for (Paths::iterator i = paths.begin(); i != paths.end(); ++i) {
+ if (!pathExists(*i)) {
+ printMsg(lvlError, format("path `%1%' disappeared") % *i);
+ invalidatePath(txn, *i);
+ } else if (!isStorePath(*i)) {
+ printMsg(lvlError, format("path `%1%' is not in the Nix store") % *i);
+ invalidatePath(txn, *i);
+ } else {
+ if (checkContents) {
+ debug(format("checking contents of `%1%'") % *i);
+ Hash expected = queryHash(txn, *i);
+ Hash current = hashPath(expected.type, *i);
+ if (current != expected) {
+ printMsg(lvlError, format("path `%1%' was modified! "
+ "expected hash `%2%', got `%3%'")
+ % *i % printHash(expected) % printHash(current));
+ }
+ }
+ validPaths.insert(*i);
+ }
+ }
+
+ /* "Usable" paths are those that are valid or have a
+ substitute. */
+ PathSet usablePaths(validPaths);
+
+ /* Check that the values of the substitute mappings are valid
+ paths. */
+ Paths subKeys;
+ nixDB.enumTable(txn, dbSubstitutes, subKeys);
+ for (Paths::iterator i = subKeys.begin(); i != subKeys.end(); ++i) {
+ Substitutes subs = readSubstitutes(txn, *i);
+ if (!isStorePath(*i)) {
+ printMsg(lvlError, format("found substitutes for non-store path `%1%'") % *i);
+ nixDB.delPair(txn, dbSubstitutes, *i);
+ }
+ else if (subs.size() == 0)
+ nixDB.delPair(txn, dbSubstitutes, *i);
+ else
+ usablePaths.insert(*i);
+ }
+
+ /* Check the cleanup invariant: only usable paths can have
+ `references', `referrers', or `derivers' entries. */
+
+ /* Check the `derivers' table. */
+ Paths deriversKeys;
+ nixDB.enumTable(txn, dbDerivers, deriversKeys);
+ for (Paths::iterator i = deriversKeys.begin();
+ i != deriversKeys.end(); ++i)
+ {
+ if (usablePaths.find(*i) == usablePaths.end()) {
+ printMsg(lvlError, format("found deriver entry for unusable path `%1%'")
+ % *i);
+ nixDB.delPair(txn, dbDerivers, *i);
+ }
+ else {
+ Path deriver = queryDeriver(txn, *i);
+ if (!isStorePath(deriver)) {
+ printMsg(lvlError, format("found corrupt deriver `%1%' for `%2%'")
+ % deriver % *i);
+ nixDB.delPair(txn, dbDerivers, *i);
+ }
+ }
+ }
+
+ /* Check the `references' table. */
+ Paths referencesKeys;
+ nixDB.enumTable(txn, dbReferences, referencesKeys);
+ for (Paths::iterator i = referencesKeys.begin();
+ i != referencesKeys.end(); ++i)
+ {
+ if (usablePaths.find(*i) == usablePaths.end()) {
+ printMsg(lvlError, format("found references entry for unusable path `%1%'")
+ % *i);
+ setReferences(txn, *i, PathSet());
+ }
+ else {
+ bool isValid = validPaths.find(*i) != validPaths.end();
+ PathSet references;
+ queryReferences(txn, *i, references);
+ for (PathSet::iterator j = references.begin();
+ j != references.end(); ++j)
+ {
+ string dummy;
+ if (!nixDB.queryString(txn, dbReferrers, addPrefix(*j, *i), dummy)) {
+ printMsg(lvlError, format("missing referrer mapping from `%1%' to `%2%'")
+ % *j % *i);
+ nixDB.setString(txn, dbReferrers, addPrefix(*j, *i), "");
+ }
+ if (isValid && validPaths.find(*j) == validPaths.end()) {
+ printMsg(lvlError, format("incomplete closure: `%1%' needs missing `%2%'")
+ % *i % *j);
+ }
+ }
+ }
+ }
+
+#if 0 // !!!
+ /* Check the `referrers' table. */
+ Paths referrersKeys;
+ nixDB.enumTable(txn, dbReferrers, referrersKeys);
+ for (Paths::iterator i = referrersKeys.begin();
+ i != referrersKeys.end(); ++i)
+ {
+ if (usablePaths.find(*i) == usablePaths.end()) {
+ printMsg(lvlError, format("found referrers entry for unusable path `%1%'")
+ % *i);
+ nixDB.delPair(txn, dbReferrers, *i);
+ }
+ else {
+ PathSet referrers, newReferrers;
+ queryReferrers(txn, *i, referrers);
+ for (PathSet::iterator j = referrers.begin();
+ j != referrers.end(); ++j)
+ {
+ Paths references;
+ if (usablePaths.find(*j) == usablePaths.end()) {
+ printMsg(lvlError, format("referrer mapping from `%1%' to unusable `%2%'")
+ % *i % *j);
+ } else {
+ nixDB.queryStrings(txn, dbReferences, *j, references);
+ if (find(references.begin(), references.end(), *i) == references.end()) {
+ printMsg(lvlError, format("missing reference mapping from `%1%' to `%2%'")
+ % *j % *i);
+ /* !!! repair by inserting *i into references */
+ }
+ else newReferrers.insert(*j);
+ }
+ }
+ if (referrers != newReferrers)
+ nixDB.setStrings(txn, dbReferrers, *i,
+ Paths(newReferrers.begin(), newReferrers.end()));
+ }
+ }
+#endif
+
+ txn.commit();
+}
+
+
+/* Upgrade from schema 1 (Nix <= 0.7) to schema 2 (Nix >= 0.8). */
+static void upgradeStore07()
+{
+ printMsg(lvlError, "upgrading Nix store to new schema (this may take a while)...");
+
+ Transaction txn(nixDB);
+
+ Paths validPaths2;
+ nixDB.enumTable(txn, dbValidPaths, validPaths2);
+ PathSet validPaths(validPaths2.begin(), validPaths2.end());
+
+ std::cerr << "hashing paths...";
+ int n = 0;
+ for (PathSet::iterator i = validPaths.begin(); i != validPaths.end(); ++i) {
+ checkInterrupt();
+ string s;
+ nixDB.queryString(txn, dbValidPaths, *i, s);
+ if (s == "") {
+ Hash hash = hashPath(htSHA256, *i);
+ setHash(txn, *i, hash);
+ std::cerr << ".";
+ if (++n % 1000 == 0) {
+ txn.commit();
+ txn.begin(nixDB);
+ }
+ }
+ }
+ std::cerr << std::endl;
+
+ txn.commit();
+
+ txn.begin(nixDB);
+
+ std::cerr << "processing closures...";
+ for (PathSet::iterator i = validPaths.begin(); i != validPaths.end(); ++i) {
+ checkInterrupt();
+ if (i->size() > 6 && string(*i, i->size() - 6) == ".store") {
+ ATerm t = ATreadFromNamedFile(i->c_str());
+ if (!t) throw Error(format("cannot read aterm from `%1%'") % *i);
+
+ ATermList roots, elems;
+ if (!matchOldClosure(t, roots, elems)) continue;
+
+ for (ATermIterator j(elems); j; ++j) {
+
+ ATerm path2;
+ ATermList references2;
+ if (!matchOldClosureElem(*j, path2, references2)) continue;
+
+ Path path = aterm2String(path2);
+ if (validPaths.find(path) == validPaths.end())
+ /* Skip this path; it's invalid. This is a normal
+ condition (Nix <= 0.7 did not enforce closure
+ on closure store expressions). */
+ continue;
+
+ PathSet references;
+ for (ATermIterator k(references2); k; ++k) {
+ Path reference = aterm2String(*k);
+ if (validPaths.find(reference) == validPaths.end())
+ /* Bad reference. Set it anyway and let the
+ user fix it. */
+ printMsg(lvlError, format("closure `%1%' contains reference from `%2%' "
+ "to invalid path `%3%' (run `nix-store --verify')")
+ % *i % path % reference);
+ references.insert(reference);
+ }
+
+ PathSet prevReferences;
+ queryReferences(txn, path, prevReferences);
+ if (prevReferences.size() > 0 && references != prevReferences)
+ printMsg(lvlError, format("warning: conflicting references for `%1%'") % path);
+
+ if (references != prevReferences)
+ setReferences(txn, path, references);
+ }
+
+ std::cerr << ".";
+ }
+ }
+ std::cerr << std::endl;
+
+ /* !!! maybe this transaction is way too big */
+ txn.commit();
+}
+
+
+/* Upgrade from schema 2 (0.8 <= Nix <= 0.9) to schema 3 (Nix >=
+ 0.10). The only thing to do here is to upgrade the old `referer'
+ table (which causes quadratic complexity in some cases) to the new
+ (and properly spelled) `referrer' table. */
+static void upgradeStore09()
+{
+ /* !!! we should disallow concurrent upgrades */
+
+ printMsg(lvlError, "upgrading Nix store to new schema (this may take a while)...");
+
+ if (!pathExists(nixDBPath + "/referers")) return;
+
+ Transaction txn(nixDB);
+
+ std::cerr << "converting referers to referrers...";
+
+ TableId dbReferers = nixDB.openTable("referers"); /* sic! */
+
+ Paths referersKeys;
+ nixDB.enumTable(txn, dbReferers, referersKeys);
+
+ int n = 0;
+ for (Paths::iterator i = referersKeys.begin();
+ i != referersKeys.end(); ++i)
+ {
+ Paths referers;
+ nixDB.queryStrings(txn, dbReferers, *i, referers);
+ for (Paths::iterator j = referers.begin();
+ j != referers.end(); ++j)
+ nixDB.setString(txn, dbReferrers, addPrefix(*i, *j), "");
+ if (++n % 1000 == 0) {
+ txn.commit();
+ txn.begin(nixDB);
+ std::cerr << "|";
+ }
+ std::cerr << ".";
+ }
+
+ txn.commit();
+
+ std::cerr << std::endl;
+
+ nixDB.closeTable(dbReferers);
+
+ nixDB.deleteTable("referers");
+}
+
+
+}