libstore: asyncify Store::setOptions

Change-Id: I80d45ccdd027663a2b7c32f21a9a78fda6906044

lix/libexpr/flake/flake.cc

@@ -392,7 +392,7 @@ LockedFlake lockFlake(
 
     if (lockFlags.applyNixConfig) {
         flake.config.apply();
-        state.ctx.store->setOptions();
+        state.aio.blockOn(state.ctx.store->setOptions());
     }
 
     try {

lix/libstore/remote-store.cc

@@ -194,9 +194,12 @@ RemoteStore::ConnectionHandle RemoteStore::getConnection()
     return ConnectionHandle(connections->get());
 }
 
-void RemoteStore::setOptions()
-{
+kj::Promise<Result<void>> RemoteStore::setOptions()
+try {
     setOptions(*(getConnection().handle));
+    co_return result::success();
+} catch (...) {
+    co_return result::current_exception();
 }
 
 bool RemoteStore::isValidPathUncached(const StorePath & path)

lix/libstore/remote-store.hh

@@ -185,7 +185,7 @@ protected:
 
     virtual void setOptions(Connection & conn);
 
-    void setOptions() override;
+    kj::Promise<Result<void>> setOptions() override;
 
     struct ConnectionHandle;
 

lix/libstore/store-api.hh

@@ -897,7 +897,7 @@ public:
      * Synchronises the options of the client with those of the daemon
      * (a no-op when there’s no daemon)
      */
-    virtual void setOptions() { }
+    virtual kj::Promise<Result<void>> setOptions() { return {result::success()}; }
 
     virtual std::optional<std::string> getVersion() { return {}; }