From 1b94865540f78a04f70f30c4984fae1c20658f51 Mon Sep 17 00:00:00 2001
From: Denes Matetelki <denes.matetelki@gmail.com>
Date: Fri, 5 Jul 2013 19:38:08 +0200
Subject: [PATCH] Small Mutex refactor

---
 include/Mutex.hpp | 34 ++++++++++++++++------------------
 src/Mutex.cpp     | 36 ++++++++++++++++--------------------
 2 files changed, 32 insertions(+), 38 deletions(-)

diff --git a/include/Mutex.hpp b/include/Mutex.hpp
index 2931b87..85a5e51 100644
--- a/include/Mutex.hpp
+++ b/include/Mutex.hpp
@@ -3,43 +3,41 @@
 
 #include <pthread.h>
 
-class Mutex 
+class Mutex
 {
 
 public:
 
-  Mutex(int kind = PTHREAD_MUTEX_DEFAULT);
+  enum MutexType {
+    Normal = PTHREAD_MUTEX_NORMAL, // no deadlock check, unlock a non-locked mutex results undefined behaviour
+    ErrorCheck = PTHREAD_MUTEX_ERRORCHECK, // error returned when relock or unlocking a non-locked mutex
+    Recursive = PTHREAD_MUTEX_RECURSIVE, // Lock counting with error handling.
+    Default = PTHREAD_MUTEX_DEFAULT // equals normal
+  };
+
+  Mutex(MutexType type = MutexType::Default);
   ~Mutex();
 
-  /**
-   * Locks mutex. If already locked, the calling thread shall block until
-   * the mutex becomes available.
-   * @returns If successful, zero; otherwise, an error number.
-   */
+  MutexType getType() const { return m_type; }
+  pthread_mutex_t* getPThreadMutex() { return &m_mutex; }
+
+  // If already locked, the calling thread shall block until the mutex becomes available.
   int lock();
 
-  /**
-   *
-   */
   int unlock();
 
-  /**
-   * If currently locked, the call shall return immediately.
-   * @returns Zero if a lock acquired. Otherwise, an error number.
-   */
+  // If currently locked, the call shall return immediately.
   int tryLock( const long int intervalSec = 0,
                const long int intervalNSec = 0 );
 
-  pthread_mutex_t* getPThreadMutex();
-
-
 private:
 
   Mutex(const Mutex& m);
   Mutex& operator=(const Mutex& m);
 
   pthread_mutex_t m_mutex;
-
+  MutexType m_type;
+  pthread_mutexattr_t m_attr;
 };
 
 #endif // MUTEX_HPP
diff --git a/src/Mutex.cpp b/src/Mutex.cpp
index 6b7d54e..fc19966 100644
--- a/src/Mutex.cpp
+++ b/src/Mutex.cpp
@@ -4,24 +4,26 @@
 
 #include <time.h>
 
+namespace {
 
-pthread_mutex_t& MutexCtor( pthread_mutex_t& mutex )
-{
-  pthread_mutex_init( &mutex, 0 );
-  return mutex;
-}
+  pthread_mutex_t& MutexCtor( pthread_mutex_t& mutex )
+  {
+    pthread_mutex_init( &mutex, 0 );
+    return mutex;
+  }
 
+} // anonym namespace
 
-Mutex::Mutex( int kind )
-  : m_mutex( MutexCtor( m_mutex ) )
+
+Mutex::Mutex( MutexType type )
+  : m_mutex( MutexCtor( m_mutex ) ) // init with function
+  , m_type( type )
 {
   TRACE;
-  if ( kind != PTHREAD_MUTEX_DEFAULT ) {
-    /// @bug passing local variables address
-    pthread_mutexattr_t attr;
-    pthread_mutexattr_init( &attr );
-    pthread_mutexattr_settype( &attr, kind );
-    pthread_mutex_init( &m_mutex, &attr );
+  if ( type != PTHREAD_MUTEX_DEFAULT ) {
+    pthread_mutexattr_init( &m_attr );
+    pthread_mutexattr_settype( &m_attr, type );
+    pthread_mutex_init( &m_mutex, &m_attr );
   }
 }
 
@@ -56,10 +58,4 @@ int Mutex::tryLock( const long int intervalSec, const long int intervalNSec )
     timespec tspec = addTotimespec( intervalSec, intervalSec );
     return pthread_mutex_timedlock( &m_mutex, &tspec );
   }
-}
-
-
-pthread_mutex_t* Mutex::getPThreadMutex()
-{
-  return &m_mutex;
-}
+}
\ No newline at end of file