libstore: asyncify Store::optimiseStore

Change-Id: I443fe4bddb0bec519ee36d55060e082ae66802cc

lix/legacy/nix-store.cc

@@ -811,7 +811,7 @@ static void opOptimise(AsyncIoRoot & aio, Strings opFlags, Strings opArgs)
     if (!opArgs.empty() || !opFlags.empty())
         throw UsageError("no arguments expected");
 
-    store->optimiseStore();
+    aio.blockOn(store->optimiseStore());
 }
 
 /* Serve the nix store in a way usable by a restricted ssh user. */

lix/libstore/daemon.cc

@@ -843,7 +843,7 @@ static void performOp(AsyncIoRoot & aio, TunnelLogger * logger, ref<Store> store
 
     case WorkerProto::Op::OptimiseStore:
         logger->startWork();
-        store->optimiseStore();
+        aio.blockOn(store->optimiseStore());
         logger->stopWork();
         to << 1;
         break;

lix/libstore/local-store.hh

@@ -263,9 +263,9 @@ public:
      * Optimise the disk space usage of the Nix store by hard-linking
      * files with the same contents.
      */
-    void optimiseStore(OptimiseStats & stats);
+    kj::Promise<Result<void>> optimiseStore(OptimiseStats & stats);
 
-    void optimiseStore() override;
+    kj::Promise<Result<void>> optimiseStore() override;
 
     /**
      * Optimise a single store path. Optionally, test the encountered

lix/libstore/optimise-store.cc

@@ -1,5 +1,6 @@
 #include "lix/libstore/local-store.hh"
 #include "lix/libstore/globals.hh"
+#include "lix/libutil/result.hh"
 #include "lix/libutil/signals.hh"
 #include "lix/libutil/strings.hh"
 
@@ -256,8 +257,8 @@ void LocalStore::optimisePath_(Activity * act, OptimiseStats & stats,
 }
 
 
-void LocalStore::optimiseStore(OptimiseStats & stats)
-{
+kj::Promise<Result<void>> LocalStore::optimiseStore(OptimiseStats & stats)
+try {
     Activity act(*logger, actOptimiseStore);
 
     auto paths = queryAllValidPaths();
@@ -283,17 +284,23 @@ void LocalStore::optimiseStore(OptimiseStats & stats)
         done++;
         act.progress(done, paths.size());
     }
+    co_return result::success();
+} catch (...) {
+    co_return result::current_exception();
 }
 
-void LocalStore::optimiseStore()
-{
+kj::Promise<Result<void>> LocalStore::optimiseStore()
+try {
     OptimiseStats stats;
 
-    optimiseStore(stats);
+    TRY_AWAIT(optimiseStore(stats));
 
     printInfo("%s freed by hard-linking %d files",
         showBytes(stats.bytesFreed),
         stats.filesLinked);
+    co_return result::success();
+} catch (...) {
+    co_return result::current_exception();
 }
 
 void LocalStore::optimisePath(const Path & path, RepairFlag repair)

lix/libstore/remote-store.cc

@@ -808,12 +808,15 @@ void RemoteStore::collectGarbage(const GCOptions & options, GCResults & results)
 }
 
 
-void RemoteStore::optimiseStore()
-{
+kj::Promise<Result<void>> RemoteStore::optimiseStore()
+try {
     auto conn(getConnection());
     conn->to << WorkerProto::Op::OptimiseStore;
     conn.processStderr();
     readInt(conn->from);
+    co_return result::success();
+} catch (...) {
+    co_return result::current_exception();
 }
 
 

lix/libstore/remote-store.hh

@@ -135,7 +135,7 @@ public:
 
     void collectGarbage(const GCOptions & options, GCResults & results) override;
 
-    void optimiseStore() override;
+    kj::Promise<Result<void>> optimiseStore() override;
 
     kj::Promise<Result<bool>> verifyStore(bool checkContents, RepairFlag repair) override;
 

lix/libstore/store-api.hh

@@ -703,7 +703,7 @@ public:
      * Optimise the disk space usage of the Nix store by hard-linking files
      * with the same contents.
      */
-    virtual void optimiseStore() { };
+    virtual kj::Promise<Result<void>> optimiseStore() { return {result::success()}; }
 
     /**
      * Check the integrity of the Nix store.

lix/nix/optimise-store.cc

@@ -23,7 +23,7 @@ struct CmdOptimiseStore : StoreCommand
 
     void run(ref<Store> store) override
     {
-        store->optimiseStore();
+        aio().blockOn(store->optimiseStore());
     }
 };