Merge branch 'nix' into 'master'.

1 files changed, 333 insertions, 0 deletions

diff --git a/nix/libstore/local-store.hh b/nix/libstore/local-store.hh
new file mode 100644
index 0000000000..09639e74cf
--- /dev/null
+++ b/nix/libstore/local-store.hh
@@ -0,0 +1,333 @@
+#pragma once
+
+#include <string>
+
+#include "store-api.hh"
+#include "util.hh"
+#include "pathlocks.hh"
+
+
+class sqlite3;
+class sqlite3_stmt;
+
+
+namespace nix {
+
+
+/* Nix store and database schema version.  Version 1 (or 0) was Nix <=
+   0.7.  Version 2 was Nix 0.8 and 0.9.  Version 3 is Nix 0.10.
+   Version 4 is Nix 0.11.  Version 5 is Nix 0.12-0.16.  Version 6 is
+   Nix 1.0.  Version 7 is Nix 1.3. */
+const int nixSchemaVersion = 7;
+
+
+extern string drvsLogDir;
+
+
+struct Derivation;
+
+
+struct OptimiseStats
+{
+    unsigned long totalFiles;
+    unsigned long sameContents;
+    unsigned long filesLinked;
+    unsigned long long bytesFreed;
+    unsigned long long blocksFreed;
+    OptimiseStats()
+    {
+        totalFiles = sameContents = filesLinked = 0;
+        bytesFreed = blocksFreed = 0;
+    }
+};
+
+
+struct RunningSubstituter
+{
+    Path program;
+    Pid pid;
+    AutoCloseFD to, from, error;
+    FdSource fromBuf;
+    bool disabled;
+    RunningSubstituter() : disabled(false) { };
+};
+
+
+/* Wrapper object to close the SQLite database automatically. */
+struct SQLite
+{
+    sqlite3 * db;
+    SQLite() { db = 0; }
+    ~SQLite();
+    operator sqlite3 * () { return db; }
+};
+
+
+/* Wrapper object to create and destroy SQLite prepared statements. */
+struct SQLiteStmt
+{
+    sqlite3 * db;
+    sqlite3_stmt * stmt;
+    unsigned int curArg;
+    SQLiteStmt() { stmt = 0; }
+    void create(sqlite3 * db, const string & s);
+    void reset();
+    ~SQLiteStmt();
+    operator sqlite3_stmt * () { return stmt; }
+    void bind(const string & value);
+    void bind(int value);
+    void bind64(long long value);
+    void bind();
+};
+
+
+class LocalStore : public StoreAPI
+{
+private:
+    typedef std::map<Path, RunningSubstituter> RunningSubstituters;
+    RunningSubstituters runningSubstituters;
+
+    Path linksDir;
+
+public:
+
+    /* Initialise the local store, upgrading the schema if
+       necessary. */
+    LocalStore(bool reserveSpace = true);
+
+    ~LocalStore();
+
+    /* Implementations of abstract store API methods. */
+
+    bool isValidPath(const Path & path);
+
+    PathSet queryValidPaths(const PathSet & paths);
+
+    PathSet queryAllValidPaths();
+
+    ValidPathInfo queryPathInfo(const Path & path);
+
+    Hash queryPathHash(const Path & path);
+
+    void queryReferences(const Path & path, PathSet & references);
+
+    void queryReferrers(const Path & path, PathSet & referrers);
+
+    Path queryDeriver(const Path & path);
+
+    PathSet queryValidDerivers(const Path & path);
+
+    PathSet queryDerivationOutputs(const Path & path);
+
+    StringSet queryDerivationOutputNames(const Path & path);
+
+    Path queryPathFromHashPart(const string & hashPart);
+
+    PathSet querySubstitutablePaths(const PathSet & paths);
+
+    void querySubstitutablePathInfos(const Path & substituter,
+        PathSet & paths, SubstitutablePathInfos & infos);
+
+    void querySubstitutablePathInfos(const PathSet & paths,
+        SubstitutablePathInfos & infos);
+
+    Path addToStore(const Path & srcPath,
+        bool recursive = true, HashType hashAlgo = htSHA256,
+        PathFilter & filter = defaultPathFilter, bool repair = false);
+
+    /* Like addToStore(), but the contents of the path are contained
+       in `dump', which is either a NAR serialisation (if recursive ==
+       true) or simply the contents of a regular file (if recursive ==
+       false). */
+    Path addToStoreFromDump(const string & dump, const string & name,
+        bool recursive = true, HashType hashAlgo = htSHA256, bool repair = false);
+
+    Path addTextToStore(const string & name, const string & s,
+        const PathSet & references, bool repair = false);
+
+    void exportPath(const Path & path, bool sign,
+        Sink & sink);
+
+    Paths importPaths(bool requireSignature, Source & source);
+
+    void buildPaths(const PathSet & paths, BuildMode buildMode);
+
+    void ensurePath(const Path & path);
+
+    void addTempRoot(const Path & path);
+
+    void addIndirectRoot(const Path & path);
+
+    void syncWithGC();
+
+    Roots findRoots();
+
+    void collectGarbage(const GCOptions & options, GCResults & results);
+
+    /* Optimise the disk space usage of the Nix store by hard-linking
+       files with the same contents. */
+    void optimiseStore(OptimiseStats & stats);
+
+    /* Optimise a single store path. */
+    void optimisePath(const Path & path);
+
+    /* Check the integrity of the Nix store.  Returns true if errors
+       remain. */
+    bool verifyStore(bool checkContents, bool repair);
+
+    /* Register the validity of a path, i.e., that `path' exists, that
+       the paths referenced by it exists, and in the case of an output
+       path of a derivation, that it has been produced by a successful
+       execution of the derivation (or something equivalent).  Also
+       register the hash of the file system contents of the path.  The
+       hash must be a SHA-256 hash. */
+    void registerValidPath(const ValidPathInfo & info);
+
+    void registerValidPaths(const ValidPathInfos & infos);
+
+    /* Register that the build of a derivation with output `path' has
+       failed. */
+    void registerFailedPath(const Path & path);
+
+    /* Query whether `path' previously failed to build. */
+    bool hasPathFailed(const Path & path);
+
+    PathSet queryFailedPaths();
+
+    void clearFailedPaths(const PathSet & paths);
+
+    void vacuumDB();
+
+    /* Repair the contents of the given path by redownloading it using
+       a substituter (if available). */
+    void repairPath(const Path & path);
+
+    /* Check whether the given valid path exists and has the right
+       contents. */
+    bool pathContentsGood(const Path & path);
+
+    void markContentsGood(const Path & path);
+
+    void setSubstituterEnv();
+
+private:
+
+    Path schemaPath;
+
+    /* Lock file used for upgrading. */
+    AutoCloseFD globalLock;
+
+    /* The SQLite database object. */
+    SQLite db;
+
+    /* Some precompiled SQLite statements. */
+    SQLiteStmt stmtRegisterValidPath;
+    SQLiteStmt stmtUpdatePathInfo;
+    SQLiteStmt stmtAddReference;
+    SQLiteStmt stmtQueryPathInfo;
+    SQLiteStmt stmtQueryReferences;
+    SQLiteStmt stmtQueryReferrers;
+    SQLiteStmt stmtInvalidatePath;
+    SQLiteStmt stmtRegisterFailedPath;
+    SQLiteStmt stmtHasPathFailed;
+    SQLiteStmt stmtQueryFailedPaths;
+    SQLiteStmt stmtClearFailedPath;
+    SQLiteStmt stmtAddDerivationOutput;
+    SQLiteStmt stmtQueryValidDerivers;
+    SQLiteStmt stmtQueryDerivationOutputs;
+    SQLiteStmt stmtQueryPathFromHashPart;
+
+    /* Cache for pathContentsGood(). */
+    std::map<Path, bool> pathContentsGoodCache;
+
+    bool didSetSubstituterEnv;
+
+    int getSchema();
+
+    void openDB(bool create);
+
+    void makeStoreWritable();
+
+    unsigned long long queryValidPathId(const Path & path);
+
+    unsigned long long addValidPath(const ValidPathInfo & info, bool checkOutputs = true);
+
+    void addReference(unsigned long long referrer, unsigned long long reference);
+
+    void appendReferrer(const Path & from, const Path & to, bool lock);
+
+    void rewriteReferrers(const Path & path, bool purge, PathSet referrers);
+
+    void invalidatePath(const Path & path);
+
+    /* Delete a path from the Nix store. */
+    void invalidatePathChecked(const Path & path);
+
+    void verifyPath(const Path & path, const PathSet & store,
+        PathSet & done, PathSet & validPaths, bool repair, bool & errors);
+
+    void updatePathInfo(const ValidPathInfo & info);
+
+    void upgradeStore6();
+    void upgradeStore7();
+    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, PathSet & visited, const Path & path);
+
+    void deletePathRecursive(GCState & state, const Path & path);
+
+    bool isActiveTempFile(const GCState & state,
+        const Path & path, const string & suffix);
+
+    int openGCLock(LockType lockType);
+
+    void removeUnusedLinks(const GCState & state);
+
+    void startSubstituter(const Path & substituter,
+        RunningSubstituter & runningSubstituter);
+
+    string getLineFromSubstituter(RunningSubstituter & run);
+
+    template<class T> T getIntLineFromSubstituter(RunningSubstituter & run);
+
+    Path createTempDirInStore();
+
+    Path importPath(bool requireSignature, Source & source);
+
+    void checkDerivationOutputs(const Path & drvPath, const Derivation & drv);
+
+    void optimisePath_(OptimiseStats & stats, const Path & path);
+
+    // Internal versions that are not wrapped in retry_sqlite.
+    bool isValidPath_(const Path & path);
+    void queryReferrers_(const Path & path, PathSet & referrers);
+};
+
+
+typedef std::pair<dev_t, ino_t> Inode;
+typedef set<Inode> InodesSeen;
+
+
+/* "Fix", or canonicalise, the meta-data of the files in a store path
+   after it has been built.  In particular:
+   - the last modification date on each file is set to 1 (i.e.,
+     00:00:01 1/1/1970 UTC)
+   - the permissions are set of 444 or 555 (i.e., read-only with or
+     without execute permission; setuid bits etc. are cleared)
+   - the owner and group are set to the Nix user and group, if we're
+     running as root. */
+void canonicalisePathMetaData(const Path & path, uid_t fromUid, InodesSeen & inodesSeen);
+void canonicalisePathMetaData(const Path & path, uid_t fromUid);
+
+void canonicaliseTimestampAndPermissions(const Path & path);
+
+MakeError(PathInUse, Error);
+
+}