* Refactoring. There is now an abstract interface class StoreAPI

  containing functions that operate on the Nix store.  One
  implementation is LocalStore, which operates on the Nix store
  directly.  The next step, to enable secure multi-user Nix, is to
  create a different implementation RemoteStore that talks to a
  privileged daemon process that uses LocalStore to perform the actual
  operations.

1 files changed, 136 insertions, 0 deletions

diff --git a/src/libstore/local-store.hh b/src/libstore/local-store.hh
new file mode 100644
index 0000000000..2fd45cd7a5
--- /dev/null
+++ b/src/libstore/local-store.hh
@@ -0,0 +1,136 @@
+#ifndef __LOCAL_STORE_H
+#define __LOCAL_STORE_H
+
+#include <string>
+
+#include "store-api.hh"
+
+
+namespace nix {
+
+
+class Transaction;
+
+
+/* Nix store and database schema version.  Version 1 (or 0) was Nix <=
+   0.7.  Version 2 was Nix 0.8 and 0.8.  Version 3 is Nix 0.10 and
+   up. */
+const int nixSchemaVersion = 3;
+
+
+class LocalStore : public StoreAPI
+{
+public:
+
+    /* Open the database environment.  If `reserveSpace' is true, make
+       sure that a big empty file exists in /nix/var/nix/db/reserved.
+       If `reserveSpace' is false, delete this file if it exists.  The
+       idea is that on normal operation, the file exists; but when we
+       run the garbage collector, it is deleted.  This is to ensure
+       that the garbage collector has a small amount of disk space
+       available, which is required to open the Berkeley DB
+       environment. */
+    LocalStore(bool reserveSpace);
+
+    ~LocalStore();
+    
+    /* Implementations of abstract store API methods. */
+    
+    bool isValidPath(const Path & path);
+
+    Substitutes querySubstitutes(const Path & srcPath);
+
+    Hash queryPathHash(const Path & path);
+
+    void queryReferences(const Path & storePath,
+        PathSet & references);
+
+    void queryReferrers(const Path & storePath,
+        PathSet & referrers);
+
+    Path addToStore(const Path & srcPath);
+
+    Path addToStoreFixed(bool recursive, string hashAlgo,
+        const Path & srcPath);
+
+    Path addTextToStore(const string & suffix, const string & s,
+        const PathSet & references);
+
+private:
+    Path _addToStore(bool fixed, bool recursive,
+        string hashAlgo, const Path & _srcPath);
+};
+
+
+/* Get a transaction object. */
+void createStoreTransaction(Transaction & txn);
+
+/* Copy a path recursively. */
+void copyPath(const Path & src, const Path & dst);
+
+/* Register a substitute. */
+void registerSubstitute(const Transaction & txn,
+    const Path & srcPath, const Substitute & sub);
+
+/* Deregister all substitutes. */
+void clearSubstitutes();
+
+/* 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 succesful 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 Transaction & txn,
+    const Path & path, const Hash & hash, const PathSet & references,
+    const Path & deriver);
+
+struct ValidPathInfo 
+{
+    Path path;
+    Path deriver;
+    Hash hash;
+    PathSet references;
+};
+
+typedef list<ValidPathInfo> ValidPathInfos;
+
+void registerValidPaths(const Transaction & txn,
+    const ValidPathInfos & infos);
+
+/* "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 0 (i.e.,
+     00:00:00 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
+     in a setuid Nix installation. */
+void canonicalisePathMetaData(const Path & path);
+
+/* Checks whether a path is valid. */ 
+bool isValidPathTxn(const Transaction & txn, const Path & path);
+
+/* Sets the set of outgoing FS references for a store path.  Use with
+   care! */
+void setReferences(const Transaction & txn, const Path & storePath,
+    const PathSet & references);
+
+/* Sets the deriver of a store path.  Use with care! */
+void setDeriver(const Transaction & txn, const Path & storePath,
+    const Path & deriver);
+
+/* Query the deriver of a store path.  Return the empty string if no
+   deriver has been set. */
+Path queryDeriver(const Transaction & txn, const Path & storePath);
+
+/* Delete a value from the nixStore directory. */
+void deleteFromStore(const Path & path, unsigned long long & bytesFreed);
+
+void verifyStore(bool checkContents);
+
+ 
+}
+
+
+#endif /* !__LOCAL_STORE_H */