1 files changed, 44 insertions, 2 deletions
diff --git a/src/libstore/store-api.cc b/src/libstore/store-api.cc
index a42d11834053..b5934a0d1232 100644
--- a/src/libstore/store-api.cc
+++ b/src/libstore/store-api.cc
@@ -5,6 +5,7 @@
 #include "nar-info-disk-cache.hh"
 #include "thread-pool.hh"
 #include "json.hh"
+#include "derivations.hh"
 
 #include <future>
 
@@ -285,6 +286,19 @@ bool Store::isValidPath(const Path & storePath)
 }
 
 
+/* Default implementation for stores that only implement
+   queryPathInfoUncached(). */
+bool Store::isValidPathUncached(const Path & path)
+{
+    try {
+        queryPathInfo(path);
+        return true;
+    } catch (InvalidPath &) {
+        return false;
+    }
+}
+
+
 ref<const ValidPathInfo> Store::queryPathInfo(const Path & storePath)
 {
     std::promise<ref<ValidPathInfo>> promise;
@@ -516,6 +530,15 @@ void copyStorePath(ref<Store> srcStore, ref<Store> dstStore,
     StringSink sink;
     srcStore->narFromPath({storePath}, sink);
 
+    if (srcStore->isTrusted())
+        dontCheckSigs = true;
+
+    if (!info->narHash && dontCheckSigs) {
+        auto info2 = make_ref<ValidPathInfo>(*info);
+        info2->narHash = hashString(htSHA256, *sink.s);
+        info = info2;
+    }
+
     dstStore->addToStore(*info, sink.s, repair, dontCheckSigs);
 }
 
@@ -758,8 +781,27 @@ std::list<ref<Store>> getDefaultSubstituters()
 }
 
 
-void copyPaths(ref<Store> from, ref<Store> to, const Paths & storePaths)
-{
+void copyPaths(ref<Store> from, ref<Store> to, const Paths & storePaths, bool substitute)
+{
+    if (substitute) {
+        /* Filter out .drv files (we don't want to build anything). */
+        PathSet paths2;
+        for (auto & path : storePaths)
+            if (!isDerivation(path)) paths2.insert(path);
+        unsigned long long downloadSize, narSize;
+        PathSet willBuild, willSubstitute, unknown;
+        to->queryMissing(PathSet(paths2.begin(), paths2.end()),
+            willBuild, willSubstitute, unknown, downloadSize, narSize);
+        /* FIXME: should use ensurePath(), but it only
+           does one path at a time. */
+        if (!willSubstitute.empty())
+            try {
+                to->buildPaths(willSubstitute);
+            } catch (Error & e) {
+                printMsg(lvlError, format("warning: %1%") % e.msg());
+            }
+    }
+
     std::string copiedLabel = "copied";
 
     logger->setExpected(copiedLabel, storePaths.size());