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//  Use, modification and distribution are subject to the
//  Boost Software License, Version 1.0. (See accompanying file
//  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)

//  See http://www.boost.org for most recent version.

//  Old versions of vxWorks (namely everything below 6.x) are
//  absolutely unable to use boost. Old STLs and compilers 
//  like (GCC 2.96) . Do not even think of getting this to work, 
//  a miserable failure will  be guaranteed!
//
//  Equally, this file has been tested for RTPs (Real Time Processes)
//  only, not for DKMs (Downloadable Kernel Modules). These two types
//  of executables differ largely in the available functionality of
//  the C-library, STL, and so on. A DKM uses a C89 library with no
//  wide character support and no guarantee of ANSI C. The same Dinkum 
//  STL library is used in both contexts. 
//
//  Similarly the Dinkum abridged STL that supports the loosely specified 
//  embedded C++ standard has not been tested and is unlikely to work 
//  on anything but the simplest library.
// ====================================================================
// 
//  Additional Configuration
//  -------------------------------------------------------------------
//
//  Because of the ordering of include files and other issues the following 
//  additional definitions worked better outside this file.
//
//  When building the log library add the following to the b2 invocation
//     define=BOOST_LOG_WITHOUT_IPC
//  and 
//     -DBOOST_LOG_WITHOUT_DEFAULT_FACTORIES
//  to your compile options.
//
//  When building the test library add 
//     -DBOOST_TEST_LIMITED_SIGNAL_DETAILS
//  to your compile options
//
//  When building containers library add
//     -DHAVE_MORECORE=0
//  to your c compile options so dlmalloc heap library is compiled 
//  without brk() calls
//
// ====================================================================
//
// Some important information regarding the usage of POSIX semaphores:
// -------------------------------------------------------------------
//
// VxWorks as a real time operating system handles threads somewhat
// different from what "normal" OSes do, regarding their scheduling!
// This could lead to a scenario called "priority inversion" when using
// semaphores, see http://en.wikipedia.org/wiki/Priority_inversion.
//
// Now, VxWorks POSIX-semaphores for DKM's default to the usage of
// priority inverting semaphores, which is fine. On the other hand,
// for RTP's it defaults to using non priority inverting semaphores,
// which could easily pose a serious problem for a real time process.
//
// To change the default properties for POSIX-semaphores in VxWorks 7
// enable core > CORE_USER Menu > DEFAULT_PTHREAD_PRIO_INHERIT 
//  
// In VxWorks 6.x so as to integrate with boost. 
// - Edit the file 
//   installDir/vxworks-6.x/target/usr/src/posix/pthreadLib.c
// - Around line 917 there should be the definition of the default
//   mutex attributes:
//
//   LOCAL pthread_mutexattr_t defaultMutexAttr =
//       {
//       PTHREAD_INITIALIZED_OBJ, PTHREAD_PRIO_NONE, 0,
//       PTHREAD_MUTEX_DEFAULT
//       };
//
//   Here, replace PTHREAD_PRIO_NONE by PTHREAD_PRIO_INHERIT.
// - Around line 1236 there should be a definition for the function
//   pthread_mutexattr_init(). A couple of lines below you should
//   find a block of code like this:
//
//   pAttr->mutexAttrStatus      = PTHREAD_INITIALIZED_OBJ;
//   pAttr->mutexAttrProtocol    = PTHREAD_PRIO_NONE;
//   pAttr->mutexAttrPrioceiling = 0;
//   pAttr->mutexAttrType        = PTHREAD_MUTEX_DEFAULT;
//
//   Here again, replace PTHREAD_PRIO_NONE by PTHREAD_PRIO_INHERIT.
// - Finally, rebuild your VSB. This will rebuild the libraries
//   with the changed properties. That's it! Now, using boost should
//   no longer cause any problems with task deadlocks!
//
//  ====================================================================

// Block out all versions before vxWorks 6.x, as these don't work:
// Include header with the vxWorks version information and query them
#include <version.h>
#if !defined(_WRS_VXWORKS_MAJOR) || (_WRS_VXWORKS_MAJOR < 6)
#  error "The vxWorks version you're using is so badly outdated,\
          it doesn't work at all with boost, sorry, no chance!"
#endif

// Handle versions above 5.X but below 6.9
#if (_WRS_VXWORKS_MAJOR == 6) && (_WRS_VXWORKS_MINOR < 9)
// TODO: Starting from what version does vxWorks work with boost?
// We can't reasonably insert a #warning "" as a user hint here,
// as this will show up with every file including some boost header,
// badly bugging the user... So for the time being we just leave it.
#endif

// vxWorks specific config options:
// --------------------------------
#define BOOST_PLATFORM "vxWorks"

// Special behaviour for DKMs:
#ifdef _WRS_KERNEL
  // DKMs do not have the <cwchar>-header,
  // but apparently they do have an intrinsic wchar_t meanwhile!
#  define BOOST_NO_CWCHAR

  // Lots of wide-functions and -headers are unavailable for DKMs as well:
#  define BOOST_NO_CWCTYPE
#  define BOOST_NO_SWPRINTF
#  define BOOST_NO_STD_WSTRING