FixedSizeData::CreatePseudoRandom() is threadsafe

data/FixedSizeData.h

@@ -7,6 +7,7 @@
 #include <string>
 #include <cstring>
 #include "../assert/assert.h"
+#include "ThreadsafePseudoRandomPool.h"
 
 namespace cpputils {
 
@@ -34,7 +35,7 @@ public:
 
 private:
   FixedSizeData() {}
-  static CryptoPP::AutoSeededRandomPool &PseudoRandomPool();
+  static ThreadsafePseudoRandomPool &PseudoRandomPool();
 
   unsigned char _data[BINARY_LENGTH];
 };
@@ -48,9 +49,8 @@ template<unsigned int SIZE> constexpr unsigned int FixedSizeData<SIZE>::BINARY_L
 template<unsigned int SIZE> constexpr unsigned int FixedSizeData<SIZE>::STRING_LENGTH;
 
 template<unsigned int SIZE>
-CryptoPP::AutoSeededRandomPool &FixedSizeData<SIZE>::PseudoRandomPool() {
-  //TODO Make seeding use blocking=true (aka /dev/random instead of /dev/urandom) or offer a configuration option?
-  static CryptoPP::AutoSeededRandomPool singleton;
+ThreadsafePseudoRandomPool &FixedSizeData<SIZE>::PseudoRandomPool() {
+  static ThreadsafePseudoRandomPool singleton;
   return singleton;
 }
 

data/ThreadsafePseudoRandomPool.h

@@ -0,0 +1,34 @@
+#pragma once
+#ifndef MESSMER_CPPUTILS_DATA_THREADSAFEPSEUDORANDOMPOOL_H
+#define MESSMER_CPPUTILS_DATA_THREADSAFEPSEUDORANDOMPOOL_H
+
+#include "../macros.h"
+
+namespace cpputils {
+
+    //TODO Store a static CryptoPP::AutoSeededRandomPool (or multiple ones) and make constructor of
+    //     ThreadsafeRandomPool() be lightweight (i.e. not do seeding), so it can be called on each callsite.
+    //     Alternatively, use a singleton factory.
+
+    //TODO Test
+    class ThreadsafePseudoRandomPool {
+    public:
+        ThreadsafePseudoRandomPool() { }
+
+        void GenerateBlock(byte *data, size_t size) {
+            // TODO Provide multiple randomPools for parallelity instead of locking the only available one
+            std::unique_lock <std::mutex> lock(_mutex);
+            _pool.GenerateBlock(data, size);
+        }
+
+    private:
+        //TODO Make seeding use blocking=true (aka /dev/random instead of /dev/urandom) or offer a configuration option?
+        CryptoPP::AutoSeededRandomPool _pool;
+        std::mutex _mutex;
+
+        DISALLOW_COPY_AND_ASSIGN(ThreadsafePseudoRandomPool);
+    };
+
+}
+
+#endif