6 files changed, 24 insertions, 12 deletions

diff --git a/third_party/nix/src/nix-build/nix-build.cc b/third_party/nix/src/nix-build/nix-build.cc
index 1fb8a2f3ad..cc2d8bc2fb 100644
--- a/third_party/nix/src/nix-build/nix-build.cc
+++ b/third_party/nix/src/nix-build/nix-build.cc
@@ -359,7 +359,8 @@ static void _main(int argc, char** argv) {
     }
 
     if (!dryRun) {
-      util::OkOrThrow(store->buildPaths(paths, buildMode));
+      auto discard_logs = DiscardLogsSink();
+      util::OkOrThrow(store->buildPaths(discard_logs, paths, buildMode));
     }
   };
 
diff --git a/third_party/nix/src/nix-daemon/nix-daemon-proto.cc b/third_party/nix/src/nix-daemon/nix-daemon-proto.cc
index cbc5452a71..6d18fc4096 100644
--- a/third_party/nix/src/nix-daemon/nix-daemon-proto.cc
+++ b/third_party/nix/src/nix-daemon/nix-daemon-proto.cc
@@ -290,7 +290,7 @@ class WorkerServiceImpl final : public WorkerService::Service {
 
   Status BuildPaths(
       grpc::ServerContext*, const nix::proto::BuildPathsRequest* request,
-      grpc::ServerWriter<nix::proto::BuildEvent>* /* writer */) override {
+      grpc::ServerWriter<nix::proto::BuildEvent>* writer) override {
     return HandleExceptions(
         [&]() -> Status {
           PathSet drvs;
@@ -303,11 +303,14 @@ class WorkerServiceImpl final : public WorkerService::Service {
             return Status(grpc::StatusCode::INTERNAL, "Invalid build mode");
           }
 
+          BuildLogStreambuf log_buffer(writer);
+          std::ostream log_sink(&log_buffer);
+
           // TODO(grfn): If mode is repair and not trusted, we need to return an
           // error here (but we can't yet because we don't know anything about
           // trusted users)
           return nix::util::proto::AbslToGRPCStatus(
-              store_->buildPaths(drvs, mode.value()));
+              store_->buildPaths(log_sink, drvs, mode.value()));
         },
         __FUNCTION__);
   }
diff --git a/third_party/nix/src/nix-env/nix-env.cc b/third_party/nix/src/nix-env/nix-env.cc
index 7502a648d8..e42fc29c22 100644
--- a/third_party/nix/src/nix-env/nix-env.cc
+++ b/third_party/nix/src/nix-env/nix-env.cc
@@ -722,8 +722,10 @@ static void opSet(Globals& globals, Strings opFlags, Strings opArgs) {
     if (globals.dryRun) {
       return;
     }
+    auto discard_logs = DiscardLogsSink();
     nix::util::OkOrThrow(globals.state->store->buildPaths(
-        paths, globals.state->repair != 0u ? bmRepair : bmNormal));
+        discard_logs, paths,
+        globals.state->repair != 0u ? bmRepair : bmNormal));
   } else {
     printMissing(globals.state->store, {drv.queryOutPath()});
     if (globals.dryRun) {
diff --git a/third_party/nix/src/nix-env/user-env.cc b/third_party/nix/src/nix-env/user-env.cc
index dac0c52a81..e3124a60e3 100644
--- a/third_party/nix/src/nix-env/user-env.cc
+++ b/third_party/nix/src/nix-env/user-env.cc
@@ -38,8 +38,9 @@ bool createUserEnv(EvalState& state, DrvInfos& elems, const Path& profile,
   }
 
   DLOG(INFO) << "building user environment dependencies";
+  auto discard_logs = DiscardLogsSink();
   util::OkOrThrow(state.store->buildPaths(
-      drvsToBuild, state.repair != 0u ? bmRepair : bmNormal));
+      discard_logs, drvsToBuild, state.repair != 0u ? bmRepair : bmNormal));
 
   /* Construct the whole top level derivation. */
   PathSet references;
@@ -139,7 +140,7 @@ bool createUserEnv(EvalState& state, DrvInfos& elems, const Path& profile,
   /* Realise the resulting store expression. */
   DLOG(INFO) << "building user environment";
   util::OkOrThrow(state.store->buildPaths(
-      {topLevelDrv}, state.repair != 0u ? bmRepair : bmNormal));
+      discard_logs, {topLevelDrv}, state.repair != 0u ? bmRepair : bmNormal));
 
   /* Switch the current user environment to the output path. */
   auto store2 = state.store.dynamic_pointer_cast<LocalFSStore>();
diff --git a/third_party/nix/src/nix-store/nix-store.cc b/third_party/nix/src/nix-store/nix-store.cc
index a036fcec8b..101ab01ef9 100644
--- a/third_party/nix/src/nix-store/nix-store.cc
+++ b/third_party/nix/src/nix-store/nix-store.cc
@@ -69,7 +69,8 @@ static PathSet realisePath(Path path, bool build = true) {
 
   if (isDerivation(p.first)) {
     if (build) {
-      util::OkOrThrow(store->buildPaths({path}));
+      auto discard_logs = DiscardLogsSink();
+      util::OkOrThrow(store->buildPaths(discard_logs, {path}));
     }
     Derivation drv = store->derivationFromPath(p.first);
     rootNr++;
@@ -185,8 +186,9 @@ static void opRealise(Strings opFlags, Strings opArgs) {
   }
 
   /* Build all paths at the same time to exploit parallelism. */
-  util::OkOrThrow(
-      store->buildPaths(PathSet(paths.begin(), paths.end()), buildMode));
+  auto discard_logs = DiscardLogsSink();
+  util::OkOrThrow(store->buildPaths(
+      discard_logs, PathSet(paths.begin(), paths.end()), buildMode));
 
   if (!ignoreUnknown) {
     for (auto& i : paths) {
@@ -1004,7 +1006,8 @@ static void opServe(Strings opFlags, Strings opArgs) {
              does one path at a time. */
           if (!willSubstitute.empty()) {
             try {
-              util::OkOrThrow(store->buildPaths(willSubstitute));
+              auto discard_logs = DiscardLogsSink();
+              util::OkOrThrow(store->buildPaths(discard_logs, willSubstitute));
             } catch (Error& e) {
               LOG(WARNING) << e.msg();
             }
@@ -1066,7 +1069,8 @@ static void opServe(Strings opFlags, Strings opArgs) {
 
         try {
           MonitorFdHup monitor(in.fd);
-          util::OkOrThrow(store->buildPaths(paths));
+          auto discard_logs = DiscardLogsSink();
+          util::OkOrThrow(store->buildPaths(discard_logs, paths));
           out << 0;
         } catch (Error& e) {
           assert(e.status);
diff --git a/third_party/nix/src/nix/installables.cc b/third_party/nix/src/nix/installables.cc
index dd1202586a..b5980ce476 100644
--- a/third_party/nix/src/nix/installables.cc
+++ b/third_party/nix/src/nix/installables.cc
@@ -274,7 +274,8 @@ Buildables build(
   if (mode == DryRun) {
     printMissing(store, pathsToBuild);
   } else if (mode == Build) {
-    util::OkOrThrow(store->buildPaths(pathsToBuild));
+    auto discard_logs = DiscardLogsSink();
+    util::OkOrThrow(store->buildPaths(discard_logs, pathsToBuild));
   }
 
   return buildables;