* nix-store --dump-db / --load-db to dump/load the Nix DB.

* nix-store --register-validity: option to supply the content hash of
  each path.
* Removed compatibility with Nix <= 0.7 stores.

9 files changed, 130 insertions, 137 deletions

diff --git a/doc/manual/release-notes.xml b/doc/manual/release-notes.xml
index 656a28fca..906a772c8 100644
--- a/doc/manual/release-notes.xml
+++ b/doc/manual/release-notes.xml
@@ -8,6 +8,19 @@
 
 <!--==================================================================-->
 
+<section xml:id="ssec-relnotes-0.12"><title>Release 0.12 (TBA)</title>
+
+<itemizedlist>
+
+  <listitem><para><command>nix-store --dump-db / --load-db</command>.</para></listitem>
+
+</itemizedlist>
+
+</section>
+
+
+<!--==================================================================-->
+
 <section xml:id="ssec-relnotes-0.11"><title>Release 0.11 (December 31,
 2007)</title>
 
diff --git a/src/libstore/build.cc b/src/libstore/build.cc
index af54b161e..a4f9c469c 100644
--- a/src/libstore/build.cc
+++ b/src/libstore/build.cc
@@ -1263,34 +1263,6 @@ string showPaths(const PathSet & paths)
 }
 
 
-/* Return a string accepted by `nix-store --register-validity' that
-   registers the specified paths as valid.  Note: it's the
-   responsibility of the caller to provide a closure. */
-static string makeValidityRegistration(const PathSet & paths,
-    bool showDerivers)
-{
-    string s = "";
-    
-    for (PathSet::iterator i = paths.begin(); i != paths.end(); ++i) {
-        s += *i + "\n";
-
-        Path deriver = showDerivers ? store->queryDeriver(*i) : "";
-        s += deriver + "\n";
-
-        PathSet references;
-        store->queryReferences(*i, references);
-
-        s += (format("%1%\n") % references.size()).str();
-            
-        for (PathSet::iterator j = references.begin();
-             j != references.end(); ++j)
-            s += *j + "\n";
-    }
-
-    return s;
-}
-
-
 DerivationGoal::HookReply DerivationGoal::tryBuildHook()
 {
     if (!useBuildHook) return rpDecline;
@@ -1417,7 +1389,7 @@ DerivationGoal::HookReply DerivationGoal::tryBuildHook()
         /* The `references' file has exactly the format accepted by
            `nix-store --register-validity'. */
         writeStringToFile(referencesFN,
-            makeValidityRegistration(allInputs, true));
+            makeValidityRegistration(allInputs, true, false));
 
         /* Tell the hook to proceed. */ 
         writeLine(toHook.writeSide, "okay");
@@ -1662,7 +1634,7 @@ void DerivationGoal::startBuilder()
         /* !!! in secure Nix, the writing should be done on the
            build uid for security (maybe). */
         writeStringToFile(tmpDir + "/" + fileName,
-            makeValidityRegistration(refs, false));
+            makeValidityRegistration(refs, false, false));
     }
 
     // The same for derivations
@@ -1701,7 +1673,7 @@ void DerivationGoal::startBuilder()
         /* !!! in secure Nix, the writing should be done on the
            build uid for security (maybe). */
         writeStringToFile(tmpDir + "/" + fileName,
-            makeValidityRegistration(refs, false));
+            makeValidityRegistration(refs, false, false));
     }
     
     
diff --git a/src/libstore/local-store.cc b/src/libstore/local-store.cc
index 7b3b7355e..12a73b70c 100644
--- a/src/libstore/local-store.cc
+++ b/src/libstore/local-store.cc
@@ -56,7 +56,6 @@ static TableId dbReferrers = 0;
 static TableId dbDerivers = 0;
 
 
-static void upgradeStore07();
 static void upgradeStore09();
 static void upgradeStore11();
 
@@ -128,12 +127,12 @@ LocalStore::LocalStore(bool reserveSpace)
             % curSchema % nixSchemaVersion);
 
     if (curSchema < nixSchemaVersion) {
+        if (curSchema == 0) /* new store */
+            curSchema = nixSchemaVersion;
         if (curSchema <= 1)
-            upgradeStore07();
-        if (curSchema == 2)
-            upgradeStore09();
-        if (curSchema == 3)
-            upgradeStore11();
+            throw Error("your Nix store is no longer supported");
+        if (curSchema <= 2) upgradeStore09();
+        if (curSchema <= 3) upgradeStore11();
         writeFile(schemaFN, (format("%1%") % nixSchemaVersion).str());
     }
 }
@@ -261,6 +260,14 @@ bool LocalStore::isValidPath(const Path & path)
 }
 
 
+PathSet LocalStore::queryValidPaths()
+{
+    Paths paths;
+    nixDB.enumTable(noTxn, dbValidPaths, paths);
+    return PathSet(paths.begin(), paths.end());
+}
+
+
 static string addPrefix(const string & prefix, const string & s)
 {
     return prefix + string(1, (char) 0) + s;
@@ -1069,93 +1076,6 @@ void LocalStore::optimiseStore(bool dryRun, OptimiseStats & stats)
 }
 
 
-/* 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
diff --git a/src/libstore/local-store.hh b/src/libstore/local-store.hh
index 6c366167f..9e6130013 100644
--- a/src/libstore/local-store.hh
+++ b/src/libstore/local-store.hh
@@ -59,6 +59,8 @@ public:
     
     bool isValidPath(const Path & path);
 
+    PathSet queryValidPaths();
+    
     Hash queryPathHash(const Path & path);
 
     void queryReferences(const Path & path, PathSet & references);
diff --git a/src/libstore/remote-store.cc b/src/libstore/remote-store.cc
index cc847c050..88a2fca8a 100644
--- a/src/libstore/remote-store.cc
+++ b/src/libstore/remote-store.cc
@@ -185,6 +185,12 @@ bool RemoteStore::isValidPath(const Path & path)
 }
 
 
+PathSet RemoteStore::queryValidPaths()
+{
+    throw Error("not implemented");
+}
+
+
 bool RemoteStore::hasSubstitutes(const Path & path)
 {
     writeInt(wopHasSubstitutes, to);
diff --git a/src/libstore/remote-store.hh b/src/libstore/remote-store.hh
index 01cac93a4..1501591e2 100644
--- a/src/libstore/remote-store.hh
+++ b/src/libstore/remote-store.hh
@@ -27,6 +27,8 @@ public:
     
     bool isValidPath(const Path & path);
 
+    PathSet queryValidPaths();
+    
     Hash queryPathHash(const Path & path);
 
     void queryReferences(const Path & path, PathSet & references);
diff --git a/src/libstore/store-api.cc b/src/libstore/store-api.cc
index 22a66ccab..b5bc85e18 100644
--- a/src/libstore/store-api.cc
+++ b/src/libstore/store-api.cc
@@ -151,11 +151,47 @@ Path computeStorePathForText(const string & suffix, const string & s,
 }
 
 
-ValidPathInfo decodeValidPathInfo(std::istream & str)
+/* Return a string accepted by decodeValidPathInfo() that
+   registers the specified paths as valid.  Note: it's the
+   responsibility of the caller to provide a closure. */
+string makeValidityRegistration(const PathSet & paths,
+    bool showDerivers, bool showHash)
+{
+    string s = "";
+    
+    for (PathSet::iterator i = paths.begin(); i != paths.end(); ++i) {
+        s += *i + "\n";
+
+        if (showHash)
+            s += printHash(store->queryPathHash(*i)) + "\n";
+
+        Path deriver = showDerivers ? store->queryDeriver(*i) : "";
+        s += deriver + "\n";
+
+        PathSet references;
+        store->queryReferences(*i, references);
+
+        s += (format("%1%\n") % references.size()).str();
+            
+        for (PathSet::iterator j = references.begin();
+             j != references.end(); ++j)
+            s += *j + "\n";
+    }
+
+    return s;
+}
+
+
+ValidPathInfo decodeValidPathInfo(std::istream & str, bool hashGiven)
 {
     ValidPathInfo info;
     getline(str, info.path);
     if (str.eof()) { info.path = ""; return info; }
+    if (hashGiven) {
+        string s;
+        getline(str, s);
+        info.hash = parseHash(htSHA256, s);
+    }
     getline(str, info.deriver);
     string s; int n;
     getline(str, s);
diff --git a/src/libstore/store-api.hh b/src/libstore/store-api.hh
index e44259dda..39a7c9b70 100644
--- a/src/libstore/store-api.hh
+++ b/src/libstore/store-api.hh
@@ -35,6 +35,9 @@ public:
     /* Checks whether a path is valid. */ 
     virtual bool isValidPath(const Path & path) = 0;
 
+    /* Query the set of valid paths. */
+    virtual PathSet queryValidPaths() = 0;
+
     /* Queries the hash of a valid path. */ 
     virtual Hash queryPathHash(const Path & path) = 0;
 
@@ -249,6 +252,9 @@ extern boost::shared_ptr<StoreAPI> store;
 boost::shared_ptr<StoreAPI> openStore(bool reserveSpace = true);
 
 
+string makeValidityRegistration(const PathSet & paths,
+    bool showDerivers, bool showHash);
+    
 struct ValidPathInfo 
 {
     Path path;
@@ -257,7 +263,8 @@ struct ValidPathInfo
     PathSet references;
 };
 
-ValidPathInfo decodeValidPathInfo(std::istream & str);
+ValidPathInfo decodeValidPathInfo(std::istream & str,
+    bool hashGiven = false);
 
 
 }
diff --git a/src/nix-store/nix-store.cc b/src/nix-store/nix-store.cc
index f0e36463d..17b3c18fa 100644
--- a/src/nix-store/nix-store.cc
+++ b/src/nix-store/nix-store.cc
@@ -401,26 +401,31 @@ static void opReadLog(Strings opFlags, Strings opArgs)
 }
 
 
-static void opRegisterValidity(Strings opFlags, Strings opArgs)
+static void opDumpDB(Strings opFlags, Strings opArgs)
 {
-    bool reregister = false; // !!! maybe this should be the default
-        
-    for (Strings::iterator i = opFlags.begin();
-         i != opFlags.end(); ++i)
-        if (*i == "--reregister") reregister = true;
-        else throw UsageError(format("unknown flag `%1%'") % *i);
+    if (!opFlags.empty()) throw UsageError("unknown flag");
+    if (!opArgs.empty())
+        throw UsageError("no arguments expected");
+    PathSet validPaths = store->queryValidPaths();
+    /* !!! this isn't streamy; makeValidityRegistration() builds a
+       potentially gigantic string. */
+    cout << makeValidityRegistration(validPaths, true, true);
+}
 
-    if (!opArgs.empty()) throw UsageError("no arguments expected");
 
+static void registerValidity(bool reregister, bool hashGiven, bool canonicalise)
+{
     ValidPathInfos infos;
     
     while (1) {
-        ValidPathInfo info = decodeValidPathInfo(cin);
+        ValidPathInfo info = decodeValidPathInfo(cin, hashGiven);
         if (info.path == "") break;
         if (!store->isValidPath(info.path) || reregister) {
             /* !!! races */
-            canonicalisePathMetaData(info.path);
-            info.hash = hashPath(htSHA256, info.path);
+            if (canonicalise)
+                canonicalisePathMetaData(info.path);
+            if (!hashGiven)
+                info.hash = hashPath(htSHA256, info.path);
             infos.push_back(info);
         }
     }
@@ -432,6 +437,32 @@ static void opRegisterValidity(Strings opFlags, Strings opArgs)
 }
 
 
+static void opLoadDB(Strings opFlags, Strings opArgs)
+{
+    if (!opFlags.empty()) throw UsageError("unknown flag");
+    if (!opArgs.empty())
+        throw UsageError("no arguments expected");
+    registerValidity(true, true, false);
+}
+
+
+static void opRegisterValidity(Strings opFlags, Strings opArgs)
+{
+    bool reregister = false; // !!! maybe this should be the default
+    bool hashGiven = false;
+        
+    for (Strings::iterator i = opFlags.begin();
+         i != opFlags.end(); ++i)
+        if (*i == "--reregister") reregister = true;
+        else if (*i == "--hash-given") hashGiven = true;
+        else throw UsageError(format("unknown flag `%1%'") % *i);
+
+    if (!opArgs.empty()) throw UsageError("no arguments expected");
+
+    registerValidity(reregister, hashGiven, true);
+}
+
+
 static void opCheckValidity(Strings opFlags, Strings opArgs)
 {
     bool printInvalid = false;
@@ -681,6 +712,10 @@ void run(Strings args)
             op = opQuery;
         else if (arg == "--read-log" || arg == "-l")
             op = opReadLog;
+        else if (arg == "--dump-db")
+            op = opDumpDB;
+        else if (arg == "--load-db")
+            op = opLoadDB;
         else if (arg == "--register-validity")
             op = opRegisterValidity;
         else if (arg == "--check-validity")