From ec62df2ad739fd4a6c72f16188c2363b6c240cdb Mon Sep 17 00:00:00 2001
From: Andrew Bell <andrew.bell.ia@gmail.com>
Date: Tue, 19 Oct 2021 13:32:05 -0400
Subject: [PATCH] We we try to write an empty buffer, replace it in the buffer
 cache.

---
 epf/Cell.cpp   | 2 ++
 epf/Writer.cpp | 6 ++++++
 epf/Writer.hpp | 1 +
 3 files changed, 9 insertions(+)

diff --git a/epf/Cell.cpp b/epf/Cell.cpp
index bb0d1c7..b8324b2 100644
--- a/epf/Cell.cpp
+++ b/epf/Cell.cpp
@@ -41,6 +41,8 @@ void Cell::write()
     size_t size = m_pos - m_buf->data();
     if (size)
         m_writer->enqueue(m_key, std::move(m_buf), size);
+    else
+        m_writer->replace(std::move(m_buf));
 }
 
 void Cell::advance()
diff --git a/epf/Writer.cpp b/epf/Writer.cpp
index 61aae47..0690508 100644
--- a/epf/Writer.cpp
+++ b/epf/Writer.cpp
@@ -78,6 +78,12 @@ void Writer::enqueue(const VoxelKey& key, DataVecPtr data, size_t dataSize)
     m_available.notify_one();
 }
 
+void Writer::replace(DataVecPtr data)
+{
+    std::lock_guard<std::mutex> lock(m_mutex);
+    m_bufferCache.replace(std::move(data));
+}
+
 void Writer::stop()
 {
     {
diff --git a/epf/Writer.hpp b/epf/Writer.hpp
index 2dde14f..05cc425 100644
--- a/epf/Writer.hpp
+++ b/epf/Writer.hpp
@@ -40,6 +40,7 @@ class Writer
 public:
     Writer(const std::string& directory, int numThreads, size_t pointSize);
 
+    void replace(DataVecPtr data);
     void enqueue(const VoxelKey& key, DataVecPtr data, size_t dataSize);
     void stop();
     const Totals& totals()