6 files changed, 9 insertions, 6 deletions
diff --git a/src/libstore/local-store.cc b/src/libstore/local-store.cc
index 201e4bae124a..37bbbfdad886 100644
--- a/src/libstore/local-store.cc
+++ b/src/libstore/local-store.cc
@@ -839,6 +839,7 @@ bool LocalStore::querySubstitutablePathInfo(const Path & substituter,
         info.references.insert(p);
     }
     info.downloadSize = getIntLine<long long>(run.from);
+    info.narSize = getIntLine<long long>(run.from);
     
     return true;
 }
diff --git a/src/libstore/misc.cc b/src/libstore/misc.cc
index d52dd6346c7a..01d6a97ae6fb 100644
--- a/src/libstore/misc.cc
+++ b/src/libstore/misc.cc
@@ -48,9 +48,9 @@ Path findOutput(const Derivation & drv, string id)
 
 void queryMissing(const PathSet & targets,
     PathSet & willBuild, PathSet & willSubstitute, PathSet & unknown,
-    unsigned long long & downloadSize)
+    unsigned long long & downloadSize, unsigned long long & narSize)
 {
-    downloadSize = 0;
+    downloadSize = narSize = 0;
     
     PathSet todo(targets.begin(), targets.end()), done;
 
@@ -88,6 +88,7 @@ void queryMissing(const PathSet & targets,
             if (store->querySubstitutablePathInfo(p, info)) {
                 willSubstitute.insert(p);
                 downloadSize += info.downloadSize;
+                narSize += info.narSize;
                 todo.insert(info.references.begin(), info.references.end());
             } else
                 unknown.insert(p);
diff --git a/src/libstore/misc.hh b/src/libstore/misc.hh
index 0bc9a2ee0d9c..abef6237e7f6 100644
--- a/src/libstore/misc.hh
+++ b/src/libstore/misc.hh
@@ -31,7 +31,7 @@ Path findOutput(const Derivation & drv, string id);
    will be substituted. */
 void queryMissing(const PathSet & targets,
     PathSet & willBuild, PathSet & willSubstitute, PathSet & unknown,
-    unsigned long long & downloadSize);
+    unsigned long long & downloadSize, unsigned long long & narSize);
 
 
 }
diff --git a/src/libstore/remote-store.cc b/src/libstore/remote-store.cc
index 08969a623d14..26093a5d3abc 100644
--- a/src/libstore/remote-store.cc
+++ b/src/libstore/remote-store.cc
@@ -191,9 +191,8 @@ void RemoteStore::setOptions()
         writeInt(logType, to);
         writeInt(printBuildTrace, to);
     }
-    if (GET_PROTOCOL_MINOR(daemonVersion) >= 6) {
+    if (GET_PROTOCOL_MINOR(daemonVersion) >= 6)
         writeInt(buildCores, to);
-    }
     processStderr();
 }
 
@@ -243,6 +242,7 @@ bool RemoteStore::querySubstitutablePathInfo(const Path & path,
     if (info.deriver != "") assertStorePath(info.deriver);
     info.references = readStorePaths(from);
     info.downloadSize = readLongLong(from);
+    info.narSize = GET_PROTOCOL_MINOR(daemonVersion) >= 7 ? readLongLong(from) : 0;
     return true;
 }
 
diff --git a/src/libstore/store-api.hh b/src/libstore/store-api.hh
index b0071da83b1b..40ac887140d7 100644
--- a/src/libstore/store-api.hh
+++ b/src/libstore/store-api.hh
@@ -87,6 +87,7 @@ struct SubstitutablePathInfo
     Path deriver;
     PathSet references;
     unsigned long long downloadSize; /* 0 = unknown or inapplicable */
+    unsigned long long narSize; /* 0 = unknown */
 };
 
 
diff --git a/src/libstore/worker-protocol.hh b/src/libstore/worker-protocol.hh
index 2764f82c2ce0..d77049bc7188 100644
--- a/src/libstore/worker-protocol.hh
+++ b/src/libstore/worker-protocol.hh
@@ -8,7 +8,7 @@ namespace nix {
 #define WORKER_MAGIC_1 0x6e697863
 #define WORKER_MAGIC_2 0x6478696f
 
-#define PROTOCOL_VERSION 0x106
+#define PROTOCOL_VERSION 0x107
 #define GET_PROTOCOL_MAJOR(x) ((x) & 0xff00)
 #define GET_PROTOCOL_MINOR(x) ((x) & 0x00ff)