Added some state-specific garbage collection code (not complete yet)

src/libstore/build.cc

@@ -1083,7 +1083,7 @@ static string makeValidityRegistration(const PathSet & paths,
         s += deriver + "\n";
 
         PathSet references;
-        store->queryReferences(*i, references, 0);				//TODO check if this is ok
+        store->queryStoreReferences(*i, references, 0);				//TODO check if this is ok
 
         s += (format("%1%\n") % references.size()).str();
             
@@ -2058,7 +2058,7 @@ void SubstitutionGoal::init()
 
     /* To maintain the closure invariant, we first have to realise the
        paths referenced by this one. */
-    store->queryReferences(storePath, references, 0);
+    store->queryStoreReferences(storePath, references, 0);
 
     for (PathSet::iterator i = references.begin();
          i != references.end(); ++i)

src/libstore/gc.cc

@@ -406,7 +406,7 @@ static void dfsVisit(const PathSet & paths, const Path & path,
     
     PathSet references;
     if (store->isValidPath(path))
-        store->queryReferences(path, references, 0);						//TODO !!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+        store->queryStoreReferences(path, references, 0);						//TODO !!!!!!!!!!!!!!!!!!!!!!!!!!!!!
     
     for (PathSet::iterator i = references.begin();
          i != references.end(); ++i)
@@ -447,7 +447,7 @@ void LocalStore::collectGarbage(GCAction action, const PathSet & pathsToDelete,
 
     /* Find the roots.  Since we've grabbed the GC lock, the set of
        permanent roots cannot increase now. */
-    Roots rootMap = ignoreLiveness ? Roots() : nix::findRoots(true);
+    Roots rootMap = ignoreLiveness ? Roots() : nix::findRoots(true);					//TODO Also find state roots?
 
     PathSet roots;
     for (Roots::iterator i = rootMap.begin(); i != rootMap.end(); ++i)
@@ -468,13 +468,17 @@ void LocalStore::collectGarbage(GCAction action, const PathSet & pathsToDelete,
     /* Determine the live paths which is just the closure of the
        roots under the `references' relation. */
     PathSet livePaths;
-    for (PathSet::const_iterator i = roots.begin(); i != roots.end(); ++i)
+    for (PathSet::const_iterator i = roots.begin(); i != roots.end(); ++i){
-        computeFSClosure(canonPath(*i), livePaths, true, false, 0);						//TODO !!!!!!!!!!!!!!!!!!!!!!!!!!! WE (MAY) ALSO NEED TO DELETE STATE??
+    	printMsg(lvlError, format("CHECK '%1%'") % *i);
+        computeFSClosure(canonPath(*i), livePaths, true, false, 0);							//TODO !!!!!!!!!!!!!!!!!!!!!!!!!!! WE (MAY) ALSO NEED TO DELETE STATE??
+    }
+	
 
     if (gcKeepDerivations) {
         for (PathSet::iterator i = livePaths.begin();
              i != livePaths.end(); ++i)
         {
+            printMsg(lvlError, format("CHECK2 '%1%'") % *i);
             /* Note that the deriver need not be valid (e.g., if we
                previously ran the collector with `gcKeepDerivations'
                turned off). */
@@ -489,6 +493,7 @@ void LocalStore::collectGarbage(GCAction action, const PathSet & pathsToDelete,
         for (PathSet::iterator i = livePaths.begin();
              i != livePaths.end(); ++i)
             if (isDerivation(*i)) {
+            	printMsg(lvlError, format("CHECK3 '%1%'") % *i);
                 Derivation drv = derivationFromPathTxn(noTxn, *i);
                 for (DerivationOutputs::iterator j = drv.outputs.begin();
                      j != drv.outputs.end(); ++j)

src/libstore/local-store.cc

@@ -33,16 +33,17 @@ static Database nixDB;
 
 /* Database tables. */
 
-/* dbValidPaths :: Path -> ()
+/* dbValidPaths :: Path -> sha256 Hash
 
    The existence of a key $p$ indicates that path $p$ is valid (that
    is, produced by a succesful build). */
 static TableId dbValidPaths = 0;
 
-/* dbValidStatePaths :: Path -> ()
+/* dbValidStatePaths :: statePath -> DrvPath
 
    The existence of a key $p$ indicates that state path $p$ is valid (that
-   is, produced by a succesful build). */
+   is, produced by a succesful build). 
+   */
 static TableId dbValidStatePaths = 0;
 
 /* dbReferences :: Path -> [Path]
@@ -445,6 +446,9 @@ static string stripPrefix(const string & prefix, const string & s)
 */
 
 
+/*
+ *  The revision can be omitted for normal store paths
+ */
 void setReferences(const Transaction & txn, const Path & store_or_statePath,
     const PathSet & references, const PathSet & stateReferences, const unsigned int revision)		
 {
@@ -529,7 +533,7 @@ void queryXReferencesTxn(const Transaction & txn, const Path & store_or_statePat
     references.insert(references2.begin(), references2.end());
 }
 
-void LocalStore::queryReferences(const Path & storePath, PathSet & references, const unsigned int revision)
+void LocalStore::queryStoreReferences(const Path & storePath, PathSet & references, const unsigned int revision)
 {
     nix::queryXReferencesTxn(noTxn, storePath, references, revision, true);
 }
@@ -539,6 +543,7 @@ void LocalStore::queryStateReferences(const Path & componentOrstatePath, PathSet
     nix::queryXReferencesTxn(noTxn, componentOrstatePath, stateReferences, revision, false);
 }
 
+//Private
 static PathSet getXReferrers(const Transaction & txn, const Path & store_or_statePath, const bool component_or_state, const unsigned int revision)
 {
     TableId table = 0;
@@ -633,7 +638,7 @@ static PathSet getXReferrers(const Transaction & txn, const Path & store_or_stat
     }
 }
 
-static PathSet getReferrersTxn(const Transaction & txn, const Path & store_or_statePath, const unsigned int revision)
+static PathSet getStoreReferrersTxn(const Transaction & txn, const Path & store_or_statePath, const unsigned int revision)
 {
 	return getXReferrers(txn, store_or_statePath, true, revision);
 }
@@ -643,19 +648,19 @@ static PathSet getStateReferrersTxn(const Transaction & txn, const Path & store_
 	return getXReferrers(txn, store_or_statePath, false, revision);
 }
 
-void queryReferrersTxn(const Transaction & txn,
+void queryStoreReferrersTxn(const Transaction & txn,
     const Path & storePath, PathSet & referrers, const unsigned int revision)
 {
     if (!isRealisableComponentOrStatePath(txn, storePath))
 		throw Error(format("path `%1%' is not valid") % storePath);
-    PathSet referrers2 = getReferrersTxn(txn, storePath, revision);
+    PathSet referrers2 = getStoreReferrersTxn(txn, storePath, revision);
     referrers.insert(referrers2.begin(), referrers2.end());
 }
 
-void LocalStore::queryReferrers(const Path & storePath,
+void LocalStore::queryStoreReferrers(const Path & storePath,
     PathSet & referrers, const unsigned int revision)
 {
-    nix::queryReferrersTxn(noTxn, storePath, referrers, revision);
+    nix::queryStoreReferrersTxn(noTxn, storePath, referrers, revision);
 }
 
 void queryStateReferrersTxn(const Transaction & txn, const Path & storePath, PathSet & stateReferrers, const unsigned int revision)
@@ -944,10 +949,10 @@ Substitutes LocalStore::querySubstitutes(const Path & path)
 }
 
 
-static void invalidatePath(Transaction & txn, const Path & path);
+static void invalidateStorePath(Transaction & txn, const Path & path);
 
 
-void clearSubstitutes()
+void clearSubstitutes()								//TODO !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! ALSO FOR STATE
 {
     Transaction txn(nixDB);
     
@@ -961,7 +966,7 @@ void clearSubstitutes()
         
         /* Maintain the cleanup invariant. */
         if (!isValidPathTxn(txn, *i))
-            invalidatePath(txn, *i);
+            invalidateStorePath(txn, *i);
     }
 
     /* !!! there should be no referrers to any of the invalid
@@ -1084,23 +1089,39 @@ void registerValidPaths(const Transaction & txn, const ValidPathInfos & infos)
     }
 }
 
-
+static void invalidatexPath(Transaction & txn, const Path & path, const bool component_or_state)
-/* Invalidate a path. The caller is responsible for checking that
-   there are no referrers. */
-static void invalidatePath(Transaction & txn, const Path & path)			//TODO Adjust for state paths????
 {
-    debug(format("unregistering path `%1%'") % path);
+	debug(format("invalidating %2% path `%1%'") % path % (component_or_state ? "store" : "state"));
 	
-    /* Clear the `references' entry for this path, as well as the
+	/* Clear the `references' entry for this path, as well as the
-       inverse `referrers' entries, and the `derivers' entry; but only
+       inverse `referrers' entries, and the `derivers' entry. */
-       if there are no substitutes for this path.  This maintains the
-       cleanup invariant. */
-    if (querySubstitutes(txn, path).size() == 0) {
-        setReferences(txn, path, PathSet(), PathSet(), -1);					//Set last references empty	(TODO is this ok?)
-        nixDB.delPair(txn, dbDerivers, path);								//TODO!!!!! also for state Derivers!!!!!!!!!!!!!!!
-    }
     
-    nixDB.delPair(txn, dbValidPaths, path);									
+    if(component_or_state)
+	    setReferences(txn, path, PathSet(), PathSet(), 0);	//This is a store path so the revision doenst matter
+    else
+    	setReferences(txn, path, PathSet(), PathSet(), 0);	//For now.... we only delete clear references for the new revision	(TODO !!!!!!!!!!!!!!!! CHECK IF WE REALLY SET IT FOR A NEW OR LAST REVISION)		
+    
+    nixDB.delPair(txn, dbDerivers, path);
+ 
+ 	if(component_or_state)
+    	nixDB.delPair(txn, dbValidPaths, path);
+    else
+    	nixDB.delPair(txn, dbValidStatePaths, path);
+ 
+ 	if(component_or_state)
+ 		nixDB.delPair(txn, dbStateInfo, path);		//We (may) need to delete if this key if path is a state-store path   
+}
+
+
+/* Invalidate a store or state path. The caller is responsible for checking that
+   there are no referrers. */
+static void invalidateStorePath(Transaction & txn, const Path & path)
+{
+	invalidatexPath(txn, path, true);
+}
+static void invalidateStatePath(Transaction & txn, const Path & path)
+{
+	invalidatexPath(txn, path, false);
 }
 
 
@@ -1391,36 +1412,54 @@ Path LocalStore::importPath(bool requireSignature, Source & source)
 }
 
 
-void deleteFromStore(const Path & _path, unsigned long long & bytesFreed)
+void deleteXFromStore(const Path & _path, unsigned long long & bytesFreed, const bool component_or_state)
 {
     bytesFreed = 0;
     Path path(canonPath(_path));
 
-    assertStorePath(path);
+	if(component_or_state)
+    	assertStorePath(path);
+    else
+    	assertStatePath(path);
 
     Transaction txn(nixDB);
-    if (isValidPathTxn(txn, path)) {
+    if (isValidPathTxn(txn, path) || isValidStatePathTxn(txn, path)) 
-        PathSet referrers = getReferrersTxn(txn, path, -1);		//delete latest referrers (TODO?)
+    {
-        for (PathSet::iterator i = referrers.begin();
+        PathSet storeReferrers = getStoreReferrersTxn(txn, path, 0);
-             i != referrers.end(); ++i)
+        PathSet stateReferrers = getStateReferrersTxn(txn, path, 0);
-            if (*i != path && isValidPathTxn(txn, *i))
-                throw PathInUse(format("cannot delete path `%1%' because it is in use by path `%2%'") % path % *i);
-        invalidatePath(txn, path);
         
-        //TODO !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Also delete/invalidate stateReferrers?????
+        for (PathSet::iterator i = storeReferrers.begin(); i != storeReferrers.end(); ++i)
+            if (*i != path && isValidPathTxn(txn, *i))
+                throw PathInUse(format("cannot delete %3% path `%1%' because it is in use by store path `%2%'") % path % *i % (component_or_state ? "store" : "state"));
+        for (PathSet::iterator i = stateReferrers.begin(); i != stateReferrers.end(); ++i)
+            if (*i != path && isValidPathTxn(txn, *i))
+                throw PathInUse(format("cannot delete %3% path `%1%' because it is in use by state path `%2%'") % path % *i % (component_or_state ? "store" : "state"));
+        
+        
+        if(component_or_state)
+        	invalidateStorePath(txn, path);
+        else
+        	invalidateStatePath(txn, path);
     }
     txn.commit();
 
     deletePathWrapped(path, bytesFreed);
 }
-
+void deleteFromStore(const Path & _path, unsigned long long & bytesFreed)
+{
+	deleteXFromStore(_path, bytesFreed, true);
+}
+void deleteFromState(const Path & _path, unsigned long long & bytesFreed)
+{
+	deleteXFromStore(_path, bytesFreed, false);
+}
 
 void verifyStore(bool checkContents)
 {
     Transaction txn(nixDB);
 
     
-    printMsg(lvlInfo, "checking path existence");
+    printMsg(lvlInfo, "checking store path existence");
 
     Paths paths;
     PathSet validPaths;
@@ -1428,18 +1467,18 @@ void verifyStore(bool checkContents)
 
     for (Paths::iterator i = paths.begin(); i != paths.end(); ++i) {
         if (!pathExists(*i)) {
-            printMsg(lvlError, format("path `%1%' disappeared") % *i);
+            printMsg(lvlError, format("store path `%1%' disappeared") % *i);
-            invalidatePath(txn, *i);
+            invalidateStorePath(txn, *i);
         } else if (!isStorePath(*i)) {
-            printMsg(lvlError, format("path `%1%' is not in the Nix store") % *i);
+            printMsg(lvlError, format("store path `%1%' is not in the Nix store") % *i);
-            invalidatePath(txn, *i);
+            invalidateStorePath(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! "
+                    printMsg(lvlError, format("store path `%1%' was modified! "
                                  "expected hash `%2%', got `%3%'")
                         % *i % printHash(expected) % printHash(current));
                 }
@@ -1448,6 +1487,24 @@ void verifyStore(bool checkContents)
         }
     }
     
+	printMsg(lvlInfo, "checking state path existence");
+
+    Paths statePaths;
+    PathSet validStatePaths;
+    nixDB.enumTable(txn, dbValidStatePaths, statePaths);
+    
+    for (Paths::iterator i = statePaths.begin(); i != statePaths.end(); ++i) {
+        if (!pathExists(*i)) {
+            printMsg(lvlError, format("state path `%1%' disappeared") % *i);
+            invalidateStatePath(txn, *i);
+        } else if (!isStatePath(*i)) {
+            printMsg(lvlError, format("state path `%1%' is not in the Nix state-store") % *i);
+            invalidateStatePath(txn, *i);
+        } else {
+            validStatePaths.insert(*i);
+        }
+    }
+
 
     printMsg(lvlInfo, "checking path realisability");
     
@@ -1456,7 +1513,8 @@ void verifyStore(bool checkContents)
     PathSet realisablePaths(validPaths);
     
     
-    //TODO Do also for validStatePaths
+    //TODO !!!!!!!!!!!!!!!!!!!!!!!!! Do also for validStatePaths
+    
 
     /* Check that the values of the substitute mappings are valid
        paths. */ 
@@ -1471,7 +1529,7 @@ void verifyStore(bool checkContents)
         else if (subs.size() == 0)
             nixDB.delPair(txn, dbSubstitutes, *i);
         else
-	    realisablePaths.insert(*i);
+			realisablePaths.insert(*i);
     }
     
 
@@ -1752,7 +1810,7 @@ void unShareStateTxn(const Transaction & txn, const Path & path, const bool bran
 
 	//Copy if necessary
 	if(branch){
-		copyContents(sharedWithOldPath, path);
+		rsyncPaths(sharedWithOldPath, path);
 	}
 	
 	//Restore the latest snapshot (non-recursive) made on this statepath

src/libstore/local-store.hh

@@ -51,11 +51,11 @@ public:
     
     Path queryStatePathDrv(const Path & statePath);
 
-    void queryReferences(const Path & path, PathSet & references, const unsigned int revision);
+    void queryStoreReferences(const Path & path, PathSet & references, const unsigned int revision);
     
     void queryStateReferences(const Path & storePath, PathSet & stateReferences, const unsigned int revision);
     
-    void queryReferrers(const Path & path, PathSet & referrers, const unsigned int revision);
+    void queryStoreReferrers(const Path & path, PathSet & referrers, const unsigned int revision);
     
     void queryStateReferrers(const Path & path, PathSet & stateReferrers, const unsigned int revision);
 
@@ -177,7 +177,7 @@ bool isValidPathTxn(const Transaction & txn, const Path & path);
 /* Sets the set of outgoing FS (also state) references for a store path.  Use with
    care! 
    
-   -1 for revision means overwrite the last revision
+   0 for revision means overwrite the last revision
    */
 void setReferences(const Transaction & txn, const Path & store_or_statePath,
     const PathSet & references, const PathSet & stateReferences, const unsigned int revision);
@@ -192,6 +192,9 @@ PathSet queryDerivers(const Transaction & txn, const Path & storePath, const str
 /* Delete a value from the nixStore directory. */
 void deleteFromStore(const Path & path, unsigned long long & bytesFreed);
 
+/* Delete a value from the nixState directory. */
+void deleteFromState(const Path & _path, unsigned long long & bytesFreed);
+
 MakeError(PathInUse, Error);
 
 void verifyStore(bool checkContents);
@@ -232,7 +235,7 @@ void queryXReferencesTxn(const Transaction & txn, const Path & path, PathSet & r
 void setStateComponentReferencesTxn(const Transaction & txn, const Path & statePath, const Strings & references, const unsigned int revision, const unsigned int timestamp);
 void setStateStateReferencesTxn(const Transaction & txn, const Path & statePath, const Strings & references, const unsigned int revision, const unsigned int timestamp);
 
-void queryReferrersTxn(const Transaction & txn, const Path & storePath, PathSet & referrers, const unsigned int revision);
+void queryStoreReferrersTxn(const Transaction & txn, const Path & storePath, PathSet & referrers, const unsigned int revision);
 void queryStateReferrersTxn(const Transaction & txn, const Path & storePath, PathSet & stateReferrers, const unsigned int revision);
 
 Path queryStatePathDrvTxn(const Transaction & txn, const Path & statePath);
@@ -263,6 +266,7 @@ bool queryStateRevisionsTxn(const Transaction & txn, const Path & statePath, Rev
 void setStatePathsIntervalTxn(const Transaction & txn, const PathSet & statePath, const IntVector & intervals, bool allZero = false);
 bool querySharedStateTxn(const Transaction & txn, const Path & statePath, Path & shared_with);
 
+
 }
 
 

src/libstore/misc.cc

@@ -73,13 +73,15 @@ void computeFSClosureRecTxn(const Transaction & txn, const Path & path, PathSet
     if (paths.find(path) != paths.end())	//takes care of double entries 
     	return;
 
+    //printMsg(lvlError, format("ComputeFSClosureRec '%1%'") % path);
+    
     paths.insert(path);
 
     PathSet references;
     PathSet stateReferences;
     
     if (flipDirection){
-        queryReferrersTxn(txn, path, references, revision);
+        queryStoreReferrersTxn(txn, path, references, revision);
        	queryStateReferrersTxn(txn, path, stateReferences, revision);
     }
     else{
@@ -143,7 +145,7 @@ void queryMissing(const PathSet & targets,
             if (store->hasSubstitutes(p))
                 willSubstitute.insert(p);
             PathSet refs;
-            store->queryReferences(p, todo, 0);		//TODO?
+            store->queryStoreReferences(p, todo, 0);		//TODO?
         }
     }
 }

src/libstore/remote-store.cc

@@ -215,10 +215,10 @@ Path RemoteStore::queryStatePathDrv(const Path & statePath)
     return readString(from);
 }
 
-void RemoteStore::queryReferences(const Path & path,
+void RemoteStore::queryStoreReferences(const Path & path,
     PathSet & references, const unsigned int revision)
 {
-    writeInt(wopQueryReferences, to);
+    writeInt(wopQueryStoreReferences, to);
     writeString(path, to);
     writeBigUnsignedInt(revision, to);
     processStderr();
@@ -238,10 +238,10 @@ void RemoteStore::queryStateReferences(const Path & path,
 }
 
 
-void RemoteStore::queryReferrers(const Path & path,
+void RemoteStore::queryStoreReferrers(const Path & path,
     PathSet & referrers, const unsigned int revision)
 {
-    writeInt(wopQueryReferrers, to);
+    writeInt(wopQueryStoreReferrers, to);
     writeString(path, to);
     writeBigUnsignedInt(revision, to);
     processStderr();

src/libstore/remote-store.hh

@@ -39,11 +39,11 @@ public:
     
     Path queryStatePathDrv(const Path & statePath);
 
-    void queryReferences(const Path & path, PathSet & references, const unsigned int revision);
+    void queryStoreReferences(const Path & path, PathSet & references, const unsigned int revision);
 
 	void queryStateReferences(const Path & storePath, PathSet & stateReferences, const unsigned int revision);
 
-    void queryReferrers(const Path & path, PathSet & referrers, const unsigned int revision);
+    void queryStoreReferrers(const Path & path, PathSet & referrers, const unsigned int revision);
     
     void queryStateReferrers(const Path & path, PathSet & stateReferrers, const unsigned int revision);
 

src/libstore/store-api.hh

@@ -80,7 +80,7 @@ public:
 
     /* Queries the set of outgoing FS references for a store path.
        The result is not cleared. */
-    virtual void queryReferences(const Path & path,
+    virtual void queryStoreReferences(const Path & path,
         PathSet & references, const unsigned int revision) = 0;
         
     /* Queries the set of outgoing FS state-references for a store path.
@@ -89,7 +89,7 @@ public:
 
     /* Queries the set of incoming FS references for a store path.
        The result is not cleared. */
-    virtual void queryReferrers(const Path & path,
+    virtual void queryStoreReferrers(const Path & path,
         PathSet & referrers, const unsigned int revision) = 0;
 
 	/* Queries the set of incoming FS state-references for a store path.

src/libstore/store-state.cc

@@ -108,10 +108,18 @@ void revertToRevisionTxn(const Transaction & txn, const Path & statePath, const
     RevisionClosureTS getTimestamps;
 	queryStateRevisionsTxn(txn, statePath_ns, getRivisions, getTimestamps, revision_arg);
 
-	//TODO !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
-	//include recursive
-	//lookup 0 (latest) to the real revision
 
+	//If not recursive: filter out all paths execpt statePath_ns
+	if(!recursive)	
+	{
+		Snapshots currentSS = getRivisions[statePath_ns];		//save SS of statePath_ns
+		getRivisions.clear();									//clear all
+		getRivisions[statePath_ns] = currentSS; 				//insert
+		
+		unsigned int currentTS = getTimestamps[statePath_ns];	//same as above	
+		getTimestamps.clear();
+		getTimestamps[statePath_ns] = currentTS;
+	}
 	
 
 	//Revert each statePath in the list
@@ -145,6 +153,7 @@ void revertToRevisionTxn(const Transaction & txn, const Path & statePath, const
 			Strings p_args;
 			p_args.push_back("-c");		//we use the shell to execute the cp command becuase the shell expands the '*' 
 			string cpcommand = "cp";
+			
 			if(revertPathOrFile.substr(revertPathOrFile.length() -1 , revertPathOrFile.length()) == "/"){		//is dir
 				string revert_to_path = revertPathOrFile.substr(0, revertPathOrFile.length() -1) + "@" + unsignedInt2String(epoch);
 				cpcommand += " -R " + revert_to_path + "/*";
@@ -166,7 +175,7 @@ void revertToRevisionTxn(const Transaction & txn, const Path & statePath, const
 				if(output == "")
 					continue;
 			}
-			else{																//is file
+			else{	//is file
 				cpcommand += " " + (revertPathOrFile + "@" + unsignedInt2String(epoch));
 				
 				if(epoch == 0){
@@ -186,7 +195,7 @@ void revertToRevisionTxn(const Transaction & txn, const Path & statePath, const
 		}
 		
 		
-		//*** Now also revert _state references_ to the specific revision (the revision is already converted to a timestamp here)
+		//*** Now also revert state _references_ to the specific revision (the revision is already converted to a timestamp here)
 		
 		//Query the references of the old revision (already converted to a timestamp)		
     	PathSet state_references;
@@ -198,7 +207,10 @@ void revertToRevisionTxn(const Transaction & txn, const Path & statePath, const
     	setStateComponentReferencesTxn(txn, statePath, Strings(state_references.begin(), state_references.end()), 0, newTimestamp);
 		setStateStateReferencesTxn(txn, statePath, Strings(state_stateReferences.begin(), state_stateReferences.end()), 0, newTimestamp);
 		
-		printMsg(lvlError, format("Reverted state of '%1%' to revision '%2%'") % statePath % revision_arg);
+		if(revision_arg == 0)
+			printMsg(lvlError, format("Reverted state of '%1%' to the latest revision") % statePath);	 //TODO lookup the number
+		else
+			printMsg(lvlError, format("Reverted state of '%1%' to revision '%2%'") % statePath % revision_arg);
 	}
 }
 
@@ -293,6 +305,8 @@ void scanAndUpdateAllReferencesTxn(const Transaction & txn, const Path & statePa
 	
 	//TODO check if path is not a shared path !
 	//TODO
+	//TODO Unshare the path:	
+	//TODO Path statePath_ns = toNonSharedPathTxn(txn, statePath);
 
 	//get all possible state and component references
     PathSet allComponentPaths;
@@ -714,7 +728,7 @@ bool queryAvailableStateRevisions(Database & nixDB, const Transaction & txn, Tab
     	return true;
 }
 
-void copyContents(const Path & from, const Path & to)	//TODO bool shellexpansion, bool failure for nix-env
+void rsyncPaths(const Path & from, const Path & to)	//TODO bool shellexpansion, bool failure for nix-env
 {
 	//TODO Could be a symlink (to a non-existing dir)
 	/*

src/libstore/store-state.hh

@@ -68,7 +68,7 @@ namespace nix {
     	const Path & statePath, RevisionInfos & revisions);	
     
     /* Copy all files and folders recursively (also the hidden ones) from the dir from/... to the dir to/... and delete the rest in to/ (Rsync) */
-	void copyContents(const Path & from, const Path & to);
+	void rsyncPaths(const Path & from, const Path & to);
 
 }
 

src/libstore/worker-protocol.hh

@@ -18,9 +18,9 @@ typedef enum {
     wopHasSubstitutes,
     wopQueryPathHash,
     wopQueryStatePathDrv,
-    wopQueryReferences,
+    wopQueryStoreReferences,
     wopQueryStateReferences,
-    wopQueryReferrers,						//10
+    wopQueryStoreReferrers,					//10
     wopQueryStateReferrers,					
     wopAddToStore,							
     wopAddTextToStore,

src/nix-env/nix-env.cc

@@ -641,10 +641,10 @@ static void installDerivations(Globals & globals,
     			comparePaths.insert(statePath);
     			comparePaths.insert(read_statePath);
     			if(store->toNonSharedPathSet(comparePaths).size() != 1)			//TODO !!!!!!!!!!!!!??
-    				copyContents(externalState, statePath);
+    				rsyncPaths(externalState, statePath);
     		}
     		else
-    			copyContents(externalState, statePath);
+    			rsyncPaths(externalState, statePath);
 
     		deletePath(externalState);
     	}

src/nix-state/help.txt

@@ -23,13 +23,13 @@ Information:
   --version: output version information
   --help: display help
 
-Share state Operations:
+(Un)Share state Operations:
 
   --unshare: unshare this path
   --share-with=a b: make the statepath b point to a
-  --copy-from=a b: make the contents of statepath b equal to the contents of a
+  --rsync-from=a b: make the contents of statepath b equal to the contents of a
 
-Share state Options:
+Unshare state Options:
 
   --unshare-and-branch-state: 
   --unshare-and-restore-old-state: (default)

src/nix-state/nix-state.cc

@@ -279,17 +279,19 @@ static void opUnshare(Strings opFlags, Strings opArgs)
 static void opShareWith(Strings opFlags, Strings opArgs)
 {
 	Path statePath = *(opArgs.begin());
-	if(!store->isValidStatePath(statePath))
+	if(!store->isValidStatePath(statePath) || !store->isValidStatePath(share_with))
-		throw UsageError(format("Path '%1%' is not a valid state path.") % statePath);
+		throw UsageError(format("Path '%1%' or '%2%' is not a valid state path.") % statePath % share_with);
 	
 	store->shareState(statePath, share_with, false);
 }
 
 static void opCopyFrom(Strings opFlags, Strings opArgs)
 {
-	//TODO !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
+	Path statePath = *(opArgs.begin());
-	//copy_from
+	if(!store->isValidStatePath(statePath) || !store->isValidStatePath(copy_from))
-	throw UsageError(format("TODO !!!!!!!!!!!!"));
+		throw UsageError(format("Path '%1%' or '%2%' is not a valid state path.") % statePath % copy_from);
+	
+	rsyncPaths(copy_from, statePath);
 }
 
 
@@ -522,7 +524,7 @@ void run(Strings args)
 	printMsg(lvlError, format("NOW: '%1%'") % FileExist("/nix/store/65c7p6c8j0vy6b8fjgq8") );
 	printMsg(lvlError, format("NOW: '%1%'") % DirectoryExist("/nix/store/65c7p6c8j0vy6b8fjg") );
 
-	store = openStore();
+	
 	
 	// /nix/state/g8vby0bjfrs85qpf1jfajrcrmlawn442-hellohardcodedstateworld-1.0-
 	// /nix/state/6l93ff3bn1mk61jbdd34diafmb4aq7c6-hellohardcodedstateworld-1.0-
@@ -572,8 +574,19 @@ void run(Strings args)
 	printMsg(lvlError, format("Rsync: '%1%'") % nixRsync);
 	
 	copyContents("/nix/state/fwir6jlqygy90zadnx95zryfa8918qac-hellohardcodedstateworld-1.0-test/", "/home/wouterdb/tmp/aa/");  //TODO !!!!!!!!!!!!!!!!!!!
+	
+	
+	
+	store = openStore();
+	Hash hash;
+	PathSet references;
+	PathSet stateReferences;
+	registerValidPath(noTxn, "/nix/store/sjnaisdpqyckc75c3mjz4msi9s1662cw-hellohardcodedstateworld-1.0", hash, references, stateReferences, "/nix/store/y7abzzpiknzps5kjb4qvdxvlhvxl6slj-hellohardcodedstateworld_import-1.0.drv", 0);
 	return;
-	*/
+	
+	//*/
+
+	
 
 	/* test */
 	
@@ -647,9 +660,9 @@ void run(Strings args)
 			op = opShareWith;
 			share_with = arg.substr(13,arg.length());
 		}
-		else if (arg.substr(0,12) == "--copy-from="){
+		else if (arg.substr(0,13) == "--rsync-from="){
 			op = opCopyFrom;
-			copy_from = arg.substr(12,arg.length());
+			copy_from = arg.substr(13,arg.length());
 		}
 		
 	    /*

src/nix-store/dotgraph.cc

@@ -115,7 +115,7 @@ void printDotGraph(const PathSet & roots)
         //Lookup all references
 		PathSet references;
 		PathSet stateReferences;
-	    store->queryReferences(path, references, 0);
+	    store->queryStoreReferences(path, references, 0);
 	    store->queryStateReferences(path, stateReferences, 0);
 	    PathSet allReferences = pathSets_union(references, stateReferences);
 

src/nix-store/nix-store.cc

@@ -214,7 +214,7 @@ static void printTree(const Path & path,
 	//Lookup all references
 	PathSet references;
 	PathSet stateReferences;
-    store->queryReferences(path, references, 0);
+    store->queryStoreReferences(path, references, 0);
     store->queryStateReferences(path, stateReferences, 0);
     PathSet allReferences = pathSets_union(references, stateReferences);
     
@@ -317,9 +317,9 @@ static void opQuery(Strings opFlags, Strings opArgs)
                 if (query == qRequisites) store->storePathRequisites(path, includeOutputs, paths, true, false, revision);
                 else if (query == qRequisitesState) store->storePathRequisites(path, includeOutputs, paths, false, true, revision);
                 else if (query == qRequisitesFull) store->storePathRequisites(path, includeOutputs, paths, true, true, revision);
-                else if (query == qReferences) store->queryReferences(path, paths, revision);
+                else if (query == qReferences) store->queryStoreReferences(path, paths, revision);
                 else if (query == qStateReferences) store->queryStateReferences(path, paths, revision);
-                else if (query == qReferrers) store->queryReferrers(path,  paths, revision);
+                else if (query == qReferrers) store->queryStoreReferrers(path,  paths, revision);
                 else if (query == qStateReferrers) store->queryStateReferrers(path,  paths, revision);
                 else if (query == qReferrersClosure) computeFSClosure(path, paths, true, false, revision, true);
                 else if (query == qReferrersClosureWithState) computeFSClosure(path, paths, true, true, revision, true);
@@ -453,7 +453,7 @@ static void opRegisterSubstitutes(Strings opFlags, Strings opArgs)
         }
         if (!cin || cin.eof()) throw Error("missing input");
         registerSubstitute(txn, srcPath, sub);
-        setReferences(txn, srcPath, references, stateReferences, 0);	//state revision 0, e.g. first commit
+        setReferences(txn, srcPath, references, stateReferences, 1);	//state revision 1, e.g. first commit
     }
 
     txn.commit();

src/nix-worker/nix-worker.cc

@@ -294,16 +294,16 @@ static void performOp(Source & from, Sink & to, unsigned int op)
         break;    	
     }
 
-    case wopQueryReferences:
+    case wopQueryStoreReferences:
-    case wopQueryReferrers: {
+    case wopQueryStoreReferrers: {
         Path path = readStorePath(from);
         unsigned int revision = readBigUnsignedInt(from);
         startWork();
         PathSet paths;
-        if (op == wopQueryReferences)
+        if (op == wopQueryStoreReferences)
-            store->queryReferences(path, paths, revision);
+            store->queryStoreReferences(path, paths, revision);
         else
-            store->queryReferrers(path, paths, revision);
+            store->queryStoreReferrers(path, paths, revision);
         stopWork();
         writeStringSet(paths, to);
         break;