From f61f67ddee12a976a0a6a20652e7c545b49fa46c Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <edolstra@gmail.com>
Date: Wed, 1 Mar 2017 16:07:15 +0100
Subject: [PATCH] RemoteStore::addToStore(): Send NAR rather than string
 containing NAR

This allows the NAR to be streamed in the future (though we're not
doing that yet).
---
 src/libstore/export-import.cc    | 23 +----------------------
 src/libstore/legacy-ssh-store.cc |  4 ++--
 src/libstore/remote-store.cc     |  5 +++--
 src/libutil/serialise.hh         |  9 +++++----
 src/nix-daemon/nix-daemon.cc     | 17 ++++++++++-------
 5 files changed, 21 insertions(+), 37 deletions(-)

diff --git a/src/libstore/export-import.cc b/src/libstore/export-import.cc
index e584ae538..531f010d9 100644
--- a/src/libstore/export-import.cc
+++ b/src/libstore/export-import.cc
@@ -61,27 +61,6 @@ void Store::exportPath(const Path & path, Sink & sink)
     hashAndWriteSink << exportMagic << path << info->references << info->deriver << 0;
 }
 
-struct TeeSource : Source
-{
-    Source & readSource;
-    ref<std::string> data;
-    TeeSource(Source & readSource)
-        : readSource(readSource)
-        , data(make_ref<std::string>())
-    {
-    }
-    size_t read(unsigned char * data, size_t len)
-    {
-        size_t n = readSource.read(data, len);
-        this->data->append((char *) data, n);
-        return n;
-    }
-};
-
-struct NopSink : ParseSink
-{
-};
-
 Paths Store::importPaths(Source & source, std::shared_ptr<FSAccessor> accessor, bool dontCheckSigs)
 {
     Paths res;
@@ -92,7 +71,7 @@ Paths Store::importPaths(Source & source, std::shared_ptr<FSAccessor> accessor,
 
         /* Extract the NAR from the source. */
         TeeSource tee(source);
-        NopSink sink;
+        ParseSink sink;
         parseDump(sink, tee);
 
         uint32_t magic = readInt(source);
diff --git a/src/libstore/legacy-ssh-store.cc b/src/libstore/legacy-ssh-store.cc
index b20ff185f..031fcac95 100644
--- a/src/libstore/legacy-ssh-store.cc
+++ b/src/libstore/legacy-ssh-store.cc
@@ -169,9 +169,9 @@ struct LegacySSHStore : public Store
 
         /* FIXME: inefficient. */
         ParseSink parseSink; /* null sink; just parse the NAR */
-        SavingSourceAdapter savedNAR(conn->from);
+        TeeSource savedNAR(conn->from);
         parseDump(parseSink, savedNAR);
-        sink(savedNAR.s);
+        sink(*savedNAR.data);
     }
 
     /* Unsupported methods. */
diff --git a/src/libstore/remote-store.cc b/src/libstore/remote-store.cc
index 642825914..47413d573 100644
--- a/src/libstore/remote-store.cc
+++ b/src/libstore/remote-store.cc
@@ -378,8 +378,9 @@ void RemoteStore::addToStore(const ValidPathInfo & info, const ref<std::string>
         conn->to << wopAddToStoreNar
                  << info.path << info.deriver << printHash(info.narHash)
                  << info.references << info.registrationTime << info.narSize
-                 << info.ultimate << info.sigs << info.ca << *nar << repair << dontCheckSigs;
-        // FIXME: don't send nar as a string
+                 << info.ultimate << info.sigs << info.ca
+                 << repair << dontCheckSigs;
+        conn->to(*nar);
         conn->processStderr();
     }
 }
diff --git a/src/libutil/serialise.hh b/src/libutil/serialise.hh
index 3072f422e..2bdee7080 100644
--- a/src/libutil/serialise.hh
+++ b/src/libutil/serialise.hh
@@ -140,15 +140,16 @@ struct StringSource : Source
 
 
 /* Adapter class of a Source that saves all data read to `s'. */
-struct SavingSourceAdapter : Source
+struct TeeSource : Source
 {
     Source & orig;
-    string s;
-    SavingSourceAdapter(Source & orig) : orig(orig) { }
+    ref<std::string> data;
+    TeeSource(Source & orig)
+        : orig(orig), data(make_ref<std::string>()) { }
     size_t read(unsigned char * data, size_t len)
     {
         size_t n = orig.read(data, len);
-        s.append((const char *) data, n);
+        this->data->append((const char *) data, n);
         return n;
     }
 };
diff --git a/src/nix-daemon/nix-daemon.cc b/src/nix-daemon/nix-daemon.cc
index a1b3f2f6f..174821884 100644
--- a/src/nix-daemon/nix-daemon.cc
+++ b/src/nix-daemon/nix-daemon.cc
@@ -283,7 +283,7 @@ static void performOp(ref<LocalStore> store, bool trusted, unsigned int clientVe
         }
         HashType hashAlgo = parseHashType(s);
 
-        SavingSourceAdapter savedNAR(from);
+        TeeSource savedNAR(from);
         RetrieveRegularNARSink savedRegular;
 
         if (recursive) {
@@ -297,7 +297,7 @@ static void performOp(ref<LocalStore> store, bool trusted, unsigned int clientVe
 
         startWork();
         if (!savedRegular.regular) throw Error("regular file expected");
-        Path path = store->addToStoreFromDump(recursive ? savedNAR.s : savedRegular.s, baseName, recursive, hashAlgo);
+        Path path = store->addToStoreFromDump(recursive ? *savedNAR.data : savedRegular.s, baseName, recursive, hashAlgo);
         stopWork();
 
         to << path;
@@ -569,6 +569,7 @@ static void performOp(ref<LocalStore> store, bool trusted, unsigned int clientVe
     }
 
     case wopAddToStoreNar: {
+        bool repair, dontCheckSigs;
         ValidPathInfo info;
         info.path = readStorePath(*store, from);
         from >> info.deriver;
@@ -578,14 +579,16 @@ static void performOp(ref<LocalStore> store, bool trusted, unsigned int clientVe
         info.references = readStorePaths<PathSet>(*store, from);
         from >> info.registrationTime >> info.narSize >> info.ultimate;
         info.sigs = readStrings<StringSet>(from);
-        from >> info.ca;
-        auto nar = make_ref<std::string>(readString(from));
-        bool repair, dontCheckSigs;
-        from >> repair >> dontCheckSigs;
+        from >> info.ca >> repair >> dontCheckSigs;
         if (!trusted && dontCheckSigs)
             dontCheckSigs = false;
+
+        TeeSource tee(from);
+        ParseSink sink;
+        parseDump(sink, tee);
+
         startWork();
-        store->addToStore(info, nar, repair, dontCheckSigs, nullptr);
+        store->addToStore(info, tee.data, repair, dontCheckSigs, nullptr);
         stopWork();
         break;
     }