diff --git a/src/s3fs_logger.cpp b/src/s3fs_logger.cpp
index 12b93cb..18e170e 100644
--- a/src/s3fs_logger.cpp
+++ b/src/s3fs_logger.cpp
@@ -36,7 +36,7 @@ constexpr char          S3fsLog::MSGTIMESTAMP[];
 S3fsLog*                S3fsLog::pSingleton       = nullptr;
 S3fsLog::s3fs_log_level S3fsLog::debug_level      = S3fsLog::LEVEL_CRIT;
 FILE*                   S3fsLog::logfp            = nullptr;
-std::string*            S3fsLog::plogfile         = nullptr;
+std::string             S3fsLog::logfile;
 bool                    S3fsLog::time_stamp       = true;
 
 //-------------------------------------------------------------------
@@ -86,11 +86,11 @@ bool S3fsLog::ReopenLogfile()
         S3FS_PRN_INFO("Currently the log file is output to stdout/stderr.");
         return true;
     }
-    if(!S3fsLog::plogfile){
-        S3FS_PRN_ERR("There is a problem with the path to the log file being nullptr.");
+    if(!S3fsLog::logfile.empty()){
+        S3FS_PRN_ERR("There is a problem with the path to the log file being empty.");
         return false;
     }
-    std::string tmp = *(S3fsLog::plogfile);
+    std::string tmp = S3fsLog::logfile;
     return S3fsLog::pSingleton->LowSetLogfile(tmp.c_str());
 }
 
@@ -141,12 +141,9 @@ S3fsLog::~S3fsLog()
         FILE*    oldfp = S3fsLog::logfp;
         S3fsLog::logfp = nullptr;
         if(oldfp && 0 != fclose(oldfp)){
-            S3FS_PRN_ERR("Could not close old log file(%s), but continue...", (S3fsLog::plogfile ? S3fsLog::plogfile->c_str() : "null"));
-        }
-        if(S3fsLog::plogfile){
-            delete S3fsLog::plogfile;
-            S3fsLog::plogfile = nullptr;
+            S3FS_PRN_ERR("Could not close old log file(%s), but continue...", (S3fsLog::logfile.empty() ? S3fsLog::logfile.c_str() : "null"));
         }
+        S3fsLog::logfile.clear();
         S3fsLog::pSingleton  = nullptr;
         S3fsLog::debug_level = S3fsLog::LEVEL_CRIT;
 
@@ -190,14 +187,11 @@ bool S3fsLog::LowSetLogfile(const char* pfile)
     if(!pfile){
         // close log file if it is opened
         if(S3fsLog::logfp && 0 != fclose(S3fsLog::logfp)){
-            S3FS_PRN_ERR("Could not close log file(%s).", (S3fsLog::plogfile ? S3fsLog::plogfile->c_str() : "null"));
+            S3FS_PRN_ERR("Could not close log file(%s).", (S3fsLog::logfile.empty() ? S3fsLog::logfile.c_str() : "null"));
             return false;
         }
         S3fsLog::logfp = nullptr;
-        if(S3fsLog::plogfile){
-            delete S3fsLog::plogfile;
-            S3fsLog::plogfile = nullptr;
-        }
+        S3fsLog::logfile.clear();
     }else{
         // open new log file
         //
@@ -213,13 +207,12 @@ bool S3fsLog::LowSetLogfile(const char* pfile)
         // switch new log file and close old log file if it is opened
         FILE*    oldfp = S3fsLog::logfp;
         if(oldfp && 0 != fclose(oldfp)){
-            S3FS_PRN_ERR("Could not close old log file(%s).", (S3fsLog::plogfile ? S3fsLog::plogfile->c_str() : "null"));
+            S3FS_PRN_ERR("Could not close old log file(%s).", (!S3fsLog::logfile.empty() ? S3fsLog::logfile.c_str() : "null"));
             fclose(newfp);
             return false;
         }
         S3fsLog::logfp = newfp;
-        delete S3fsLog::plogfile;
-        S3fsLog::plogfile = new std::string(pfile);
+        S3fsLog::logfile = pfile;
     }
     return true;
 }
diff --git a/src/s3fs_logger.h b/src/s3fs_logger.h
index 750169f..94d9d0c 100644
--- a/src/s3fs_logger.h
+++ b/src/s3fs_logger.h
@@ -59,7 +59,7 @@ class S3fsLog
         static S3fsLog*       pSingleton;
         static s3fs_log_level debug_level;
         static FILE*          logfp;
-        static std::string*   plogfile;
+        static std::string    logfile;
         static bool           time_stamp;
 
     protected:
diff --git a/src/sighandlers.cpp b/src/sighandlers.cpp
index 295d099..81055fc 100644
--- a/src/sighandlers.cpp
+++ b/src/sighandlers.cpp
@@ -29,7 +29,7 @@
 //-------------------------------------------------------------------
 // Class S3fsSignals
 //-------------------------------------------------------------------
-S3fsSignals* S3fsSignals::pSingleton = nullptr;
+std::unique_ptr<S3fsSignals> S3fsSignals::pSingleton;
 bool S3fsSignals::enableUsr1         = false;
 
 //-------------------------------------------------------------------
@@ -38,15 +38,14 @@ bool S3fsSignals::enableUsr1         = false;
 bool S3fsSignals::Initialize()
 {
     if(!S3fsSignals::pSingleton){
-        S3fsSignals::pSingleton = new S3fsSignals;
+        S3fsSignals::pSingleton.reset(new S3fsSignals);
     }
     return true;
 }
 
 bool S3fsSignals::Destroy()
 {
-    delete S3fsSignals::pSingleton;
-    S3fsSignals::pSingleton = nullptr;
+    S3fsSignals::pSingleton.reset();
     return true;
 }
 
@@ -168,7 +167,7 @@ bool S3fsSignals::InitHupHandler()
 //-------------------------------------------------------------------
 // Methods
 //-------------------------------------------------------------------
-S3fsSignals::S3fsSignals() : pThreadUsr1(nullptr), pSemUsr1(nullptr)
+S3fsSignals::S3fsSignals()
 {
     if(S3fsSignals::enableUsr1){
         if(!InitUsr1Handler()){
@@ -201,16 +200,14 @@ bool S3fsSignals::InitUsr1Handler()
 
     // create thread
     int result;
-    pSemUsr1    = new Semaphore(0);
-    pThreadUsr1 = new pthread_t;
-    if(0 != (result = pthread_create(pThreadUsr1, nullptr, S3fsSignals::CheckCacheWorker, static_cast<void*>(pSemUsr1)))){
+    std::unique_ptr<Semaphore> pSemUsr1_tmp(new Semaphore(0));
+    std::unique_ptr<pthread_t> pThreadUsr1_tmp(new pthread_t);
+    if(0 != (result = pthread_create(pThreadUsr1.get(), nullptr, S3fsSignals::CheckCacheWorker, static_cast<void*>(pSemUsr1_tmp.get())))){
         S3FS_PRN_ERR("Could not create thread for SIGUSR1 by %d", result);
-        delete pSemUsr1;
-        delete pThreadUsr1;
-        pSemUsr1    = nullptr;
-        pThreadUsr1 = nullptr;
         return false;
     }
+    pSemUsr1 = std::move(pSemUsr1_tmp);
+    pThreadUsr1 = std::move(pThreadUsr1_tmp);
 
     // set handler
     struct sigaction sa;
@@ -244,10 +241,8 @@ bool S3fsSignals::DestroyUsr1Handler()
         S3FS_PRN_ERR("Could not stop thread for SIGUSR1 by %d", result);
         return false;
     }
-    delete pSemUsr1;
-    delete pThreadUsr1;
-    pSemUsr1    = nullptr;
-    pThreadUsr1 = nullptr;
+    pSemUsr1.reset();
+    pThreadUsr1.reset();
 
     return true;
 }
diff --git a/src/sighandlers.h b/src/sighandlers.h
index f01a116..f4996e6 100644
--- a/src/sighandlers.h
+++ b/src/sighandlers.h
@@ -21,6 +21,8 @@
 #ifndef S3FS_SIGHANDLERS_H_
 #define S3FS_SIGHANDLERS_H_
 
+#include <memory>
+
 class Semaphore;
 
 //----------------------------------------------
@@ -29,14 +31,14 @@ class Semaphore;
 class S3fsSignals
 {
     private:
-        static S3fsSignals* pSingleton;
+        static std::unique_ptr<S3fsSignals> pSingleton;
         static bool         enableUsr1;
 
-        pthread_t*          pThreadUsr1;
-        Semaphore*          pSemUsr1;
+        std::unique_ptr<pthread_t> pThreadUsr1;
+        std::unique_ptr<Semaphore> pSemUsr1;
 
     protected:
-        static S3fsSignals* get() { return pSingleton; }
+        static S3fsSignals* get() { return pSingleton.get(); }
 
         static void HandlerUSR1(int sig);
         static void* CheckCacheWorker(void* arg);
@@ -48,7 +50,6 @@ class S3fsSignals
         static bool InitHupHandler();
 
         S3fsSignals();
-        ~S3fsSignals();
         S3fsSignals(const S3fsSignals&) = delete;
         S3fsSignals(S3fsSignals&&) = delete;
         S3fsSignals& operator=(const S3fsSignals&) = delete;
@@ -59,6 +60,7 @@ class S3fsSignals
         bool WakeupUsr1Thread();
 
     public:
+        ~S3fsSignals();
         static bool Initialize();
         static bool Destroy();