CCriticalSectionEx, CThreadSafe & CThreadSafeScalar v1.01

Welcome to CCriticalSeciontEx, CThreadSafe and CThreadSafeScalar, a collection of C++ wrapper class to provide thread safe access to objects. The classes are based on the code presented in Chapter Ten of the book "Programming Applications for Microsoft Windows" by Jeffrey Richter. 

Features

• Simple and clean C++ interface.
• The code is Unicode enabled and build configurations are provided.
• The classes integrate closely with MFC. i.e. instead of the CResGuard class we use a derivative of the MFC class CCriticalSection.
• The classes provide a Critical section wrapper with timeouts and spin counts. The class also handles the case where this functionality does not exist (i.e the presence of the functions "InitializeCriticalSectionAndSpinCount", "SetCriticalSectionSpinCount" and "TryEnterCriticalSection" in Kernel32.dll). These 3 functions are not available on Windows 95, 98, 98 SE or ME.
• The CThreadSafe class (which corresponds to the Richter class CInterlockedType) uses inheritance rather than encapsulation to implement locking. This allows an instance of a class to be treated just like a critical section, for example:
  
  
  CThreadSafe<CMyClass> variable;
  CSingleLock sl(&variable, TRUE);
  
  or
  
  CThreadSafe<CMyClass> variable;
  variable.Lock();
  .
  .
  variable.Unlock();
• The CThreadSafe class correctly implements the arithmetic operators. e.g. the following code works 
  correctly:
  
  CThreadSafe<int> variable(4);
  (variable++)++;
  ASSERT(variable == 6); //Richter code would have "variable" equal to 5 here
  
  The reason why the Richter would code fail was because it did not return a reference to the correct 
  object for all of the arithmetic operators.

The enclosed zip file contains the source code and a simple test program to exercise all of the classes.

Copyright

• You are allowed to include the source code in any product (commercial, shareware, freeware or otherwise) when your product is released in binary form.
• You are allowed to modify the source code in any way you want except you cannot modify the copyright details at the top of each module.
• If you want to distribute source code with your application, then you are only allowed to distribute versions released by the author. This is to maintain a single distribution point for the source code.

Updates

V1.0 (4 December 2002)

• Initial public release.

V1.01 (22 December 2006)

• Updated copyright details
• Optimized CThreadSafe constructor code
• Code now uses newer C++ style casts instead of C style casts.
• Updated the code to clean compile on VC 2005
• Made CCriticalSectionEx::Lock and Unlock non virtual
• Optimized _CRITICAL_SECTION_DATA constructor code
• CCriticalSectionEx constructors now throws an exception using AfxThrowMemoryException instead of AfxThrowResourceException
• Removed unnecessary CThreadSafe destructor
• Removed unnecessary CThreadSafeScalar destructor
• Added postfix operator support to CThreadSafeScalar
• Addition of a operator TYPE*() in CThreadSafe
• m_Value member variable of CThreadSafe is now public
• Addition of a CCRITICALSECTIONEX_EXT_CLASS preprocessor macro to allow the classes to be more easily added to an extension dll