From 5040aa8a217ba7ea5f75248f3d83cc346d7f51af Mon Sep 17 00:00:00 2001
From: Andrei Drozdov <sulverus@gmail.com>
Date: Mon, 22 Apr 2024 02:45:15 +0200
Subject: [PATCH] Templated replicated container

---
 examples/async_replication/async_replicated_container.h | 7 ++++---
 examples/async_replication/node.cc                      | 3 ++-
 examples/async_replication/vector_clock.h               | 9 ++++++---
 3 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/examples/async_replication/async_replicated_container.h b/examples/async_replication/async_replicated_container.h
index 580f2d82..03ff65e0 100644
--- a/examples/async_replication/async_replicated_container.h
+++ b/examples/async_replication/async_replicated_container.h
@@ -31,12 +31,13 @@ struct ReplicationConfig final {
   uint32_t max_waits;
 };
 
+template <class CLOCK_T>
 class AsyncReplicatedContainer {
  private:
   struct SharedState final {
     bool die = false;
     std::map<std::string, uint32_t> data;
-    std::map<std::string, VectorClock> clock;
+    std::map<std::string, CLOCK_T> clock;
     std::map<std::string, std::queue<std::pair<std::string, uint32_t> > > replication_out;
   };
 
@@ -73,7 +74,7 @@ class AsyncReplicatedContainer {
       // Set clock and send update to replication thread
       if (replicate) {
         if (state.clock.find(tuple.first) == state.clock.end()) {
-          state.clock[tuple.first] = VectorClock(nodes.size(), clock_id);
+          state.clock[tuple.first] = CLOCK_T(nodes.size(), clock_id);
         }
         state.clock[tuple.first].step();
 
@@ -155,7 +156,7 @@ class AsyncReplicatedContainer {
         state.MutableUse([&buffer, this](SharedState& state) {
           bool is_insert = state.data.find(buffer.key) == state.data.end();
           if (is_insert) {
-            state.clock[buffer.key] = VectorClock(nodes.size(), clock_id);
+            state.clock[buffer.key] = CLOCK_T(nodes.size(), clock_id);
           }
           bool is_valid_update = state.clock[buffer.key].merge(buffer.clock, is_insert);
           if (is_valid_update) {
diff --git a/examples/async_replication/node.cc b/examples/async_replication/node.cc
index ff5e5588..b996d86e 100644
--- a/examples/async_replication/node.cc
+++ b/examples/async_replication/node.cc
@@ -1,5 +1,6 @@
 #include "../../bricks/dflags/dflags.h"
 #include "async_replicated_container.h"
+#include "vector_clock.h"
 #include <random>
 
 DEFINE_string(host, "127.0.0.1", "Hostname for the server");
@@ -29,7 +30,7 @@ int main(int argc, char** argv) {
                                              false,
                                              10};
 
-  AsyncReplicatedContainer storage(conf);
+  AsyncReplicatedContainer<StrictVectorClock> storage(conf);
   storage.start();
   storage.start_monitor(keys, FLAGS_monitor_delay);
   while (true) {
diff --git a/examples/async_replication/vector_clock.h b/examples/async_replication/vector_clock.h
index 4baf778e..29ca0284 100644
--- a/examples/async_replication/vector_clock.h
+++ b/examples/async_replication/vector_clock.h
@@ -10,12 +10,12 @@ class VectorClock {
   uint32_t local_id;
 
  public:
-  VectorClock(uint32_t size, uint32_t node_id) {
+  explicit VectorClock(uint32_t size, uint32_t node_id) {
     // Set local process id and cluster size
     local_id = node_id;
     clock.resize(size, current::time::Now());
   }
-  VectorClock() {
+  explicit VectorClock() {
     // Lamport clocks for size=1
     VectorClock(1, 0);
   }
@@ -86,7 +86,10 @@ class VectorClock {
   }
 };
 
-class StrictVectorClock : VectorClock {
+class StrictVectorClock : public VectorClock {
+  using VectorClock::VectorClock;
+
+ public:
   static bool is_conflicting(Clocks &v1, Clocks &v2) {
     // Check if v1 is in sync with v2 and v1 is strictly early then v2
     return !is_parallel(v1, v2) && is_early(v1, v2);