Merge pull request #8544 from edolstra/handle-missing-gc-socket

LocalStore: :addTempRoot(): Handle ENOENT
(cherry picked from commit 7115edc85af060ef235ac0270245ab46cc828f7c)
Change-Id: Ie6b1596049c3fde09b98f2f0727899f98e48e6b1

1 files changed, 14 insertions, 8 deletions

diff --git a/src/libstore/gc.cc b/src/libstore/gc.cc
index 7c7273012..ac61f7f53 100644
--- a/src/libstore/gc.cc
+++ b/src/libstore/gc.cc
@@ -142,11 +142,12 @@ void LocalStore::addTempRoot(const StorePath & path)
             try {
                 nix::connect(fdRootsSocket->get(), socketPath);
             } catch (SysError & e) {
-                /* The garbage collector may have exited, so we need to
-                   restart. */
-                if (e.errNo == ECONNREFUSED) {
-                    debug("GC socket connection refused");
+                /* The garbage collector may have exited or not
+                   created the socket yet, so we need to restart. */
+                if (e.errNo == ECONNREFUSED || e.errNo == ENOENT) {
+                    debug("GC socket connection refused: %s", e.msg());
                     fdRootsSocket->close();
+                    std::this_thread::sleep_for(std::chrono::milliseconds(100));
                     goto restart;
                 }
                 throw;
@@ -502,6 +503,11 @@ void LocalStore::collectGarbage(const GCOptions & options, GCResults & results)
     auto fdGCLock = openGCLock();
     FdLock gcLock(fdGCLock.get(), ltWrite, true, "waiting for the big garbage collector lock...");
 
+    /* Synchronisation point to test ENOENT handling in
+       addTempRoot(), see tests/gc-non-blocking.sh. */
+    if (auto p = getEnv("_NIX_TEST_GC_SYNC_1"))
+        readFile(*p);
+
     /* Start the server for receiving new roots. */
     auto socketPath = stateDir.get() + gcSocketPath;
     createDirs(dirOf(socketPath));
@@ -625,6 +631,10 @@ void LocalStore::collectGarbage(const GCOptions & options, GCResults & results)
         roots.insert(root.first);
     }
 
+    /* Synchronisation point for testing, see tests/functional/gc-non-blocking.sh. */
+    if (auto p = getEnv("_NIX_TEST_GC_SYNC_2"))
+        readFile(*p);
+
     /* Helper function that deletes a path from the store and throws
        GCLimitReached if we've deleted enough garbage. */
     auto deleteFromStore = [&](std::string_view baseName)
@@ -771,10 +781,6 @@ void LocalStore::collectGarbage(const GCOptions & options, GCResults & results)
         }
     };
 
-    /* Synchronisation point for testing, see tests/functional/gc-concurrent.sh. */
-    if (auto p = getEnv("_NIX_TEST_GC_SYNC"))
-        readFile(*p);
-
     /* Either delete all garbage paths, or just the specified
        paths (for gcDeleteSpecific). */
     if (options.action == GCOptions::gcDeleteSpecific) {