minor refactor

src/util/BufferPool.hpp

@@ -0,0 +1,42 @@
+#ifndef UTIL_BUFFER_POOL_HPP_
+#define UTIL_BUFFER_POOL_HPP_
+
+#include "../typedefs.h"
+
+#include <queue>
+#include <mutex>
+#include <vector>
+#include <memory>
+
+namespace util {
+    /// @brief Thread-safe pool of same-sized buffers
+    /// @tparam T array type
+    template<class T>
+    class BufferPool {
+        std::vector<std::unique_ptr<T[]>> buffers;
+        std::queue<T*> freeBuffers;
+        std::mutex mutex;
+        size_t bufferSize;
+    public:
+        BufferPool(size_t bufferSize) : bufferSize(bufferSize) {
+        }
+
+        /// @brief Retrieve a buffer for use
+        /// @return pointer that brings buffer back to the pool when destroyed
+        std::shared_ptr<T[]> get() {
+            std::lock_guard lock(mutex);
+            if (freeBuffers.empty()) {
+                buffers.emplace_back(std::make_unique<T[]>(bufferSize));
+                freeBuffers.push(buffers[buffers.size()-1].get());
+            }
+            auto* buffer = freeBuffers.front();
+            freeBuffers.pop();
+            return std::shared_ptr<T[]>(buffer, [this](T* ptr) {
+                std::lock_guard lock(mutex);
+                freeBuffers.push(ptr);
+            });
+        }
+    };
+}
+
+#endif // UTIL_BUFFER_POOL_HPP_