From b04dc6c76e2e78b2f7ac4fb2a4f0881933e27bd0 Mon Sep 17 00:00:00 2001
From: Eelco Dolstra <edolstra@gmail.com>
Date: Thu, 19 Oct 2017 12:28:06 +0200
Subject: [PATCH] Fix root creation when the root already exists but is owned
 by another user

---
 src/hydra-queue-runner/builder.cc            | 9 ++++++++-
 src/hydra-queue-runner/hydra-queue-runner.cc | 2 ++
 src/hydra-queue-runner/queue-monitor.cc      | 2 +-
 src/hydra-queue-runner/state.hh              | 2 ++
 4 files changed, 13 insertions(+), 2 deletions(-)

diff --git a/src/hydra-queue-runner/builder.cc b/src/hydra-queue-runner/builder.cc
index 8a636b17..ceaa252e 100644
--- a/src/hydra-queue-runner/builder.cc
+++ b/src/hydra-queue-runner/builder.cc
@@ -264,7 +264,7 @@ State::StepResult State::doBuildStep(nix::ref<Store> destStore,
         assert(stepNr);
 
         for (auto & path : step->drv.outputPaths())
-            writeFile(rootsDir + "/" + baseNameOf(path), "");
+            addRoot(path);
 
         /* Register success in the database for all Build objects that
            have this step as the top-level step. Since the queue
@@ -473,3 +473,10 @@ State::StepResult State::doBuildStep(nix::ref<Store> destStore,
 
     return sDone;
 }
+
+
+void State::addRoot(const Path & storePath)
+{
+    auto root = rootsDir + "/" + baseNameOf(storePath);
+    if (!pathExists(root)) writeFile(root, "");
+}
diff --git a/src/hydra-queue-runner/hydra-queue-runner.cc b/src/hydra-queue-runner/hydra-queue-runner.cc
index f0bb338e..283ca96b 100644
--- a/src/hydra-queue-runner/hydra-queue-runner.cc
+++ b/src/hydra-queue-runner/hydra-queue-runner.cc
@@ -841,6 +841,8 @@ void State::run(BuildID buildOne)
         jobsetRepeats.emplace(std::make_pair(s2[0], s2[1]), std::stoi(s2[2]));
     }
 
+    addRoot("/nix/store/rk9lahzm21qm0zjclv6mz0m4hy77wk14-vm-test-run-unnamed.drv");
+
     {
         auto conn(dbPool.get());
         clearBusy(*conn, 0);
diff --git a/src/hydra-queue-runner/queue-monitor.cc b/src/hydra-queue-runner/queue-monitor.cc
index 85d8f626..862925b2 100644
--- a/src/hydra-queue-runner/queue-monitor.cc
+++ b/src/hydra-queue-runner/queue-monitor.cc
@@ -222,7 +222,7 @@ bool State::getQueuedBuilds(Connection & conn,
             BuildOutput res = getBuildOutputCached(conn, destStore, drv);
 
             for (auto & path : drv.outputPaths())
-                writeFile(rootsDir + "/" + baseNameOf(path), "");
+                addRoot(path);
 
             {
             auto mc = startDbUpdate();
diff --git a/src/hydra-queue-runner/state.hh b/src/hydra-queue-runner/state.hh
index f5ba641e..543a36e3 100644
--- a/src/hydra-queue-runner/state.hh
+++ b/src/hydra-queue-runner/state.hh
@@ -535,6 +535,8 @@ private:
 
     void dumpStatus(Connection & conn, bool log);
 
+    void addRoot(const nix::Path & storePath);
+
 public:
 
     void showStatus();