dnl Copyright (C) 2010 Vincent Torri <vtorri at univ-evry dot fr>
dnl rwlock code added by Mike Blumenkrantz <mike at zentific dot com>
dnl This code is public domain and can be freely used or copied.

dnl Macro that check if POSIX or Win32 threads library is available or not.

dnl Usage: EFL_CHECK_THREADS(ACTION-IF-FOUND [, ACTION-IF-NOT-FOUND])
dnl Call AC_SUBST(EFL_PTHREAD_CFLAGS)
dnl Call AC_SUBST(EFL_PTHREAD_LIBS)
dnl Defines EFL_HAVE_POSIX_THREADS or EFL_HAVE_WIN32_THREADS, and EFL_HAVE_THREADS

AC_DEFUN([EFL_CHECK_THREADS],
[

dnl Generic thread detection

EFL_PTHREAD_CFLAGS="-D_REENTRANT"
EFL_PTHREAD_LIBS=""

_efl_have_posix_threads="no"
_efl_have_win32_threads="no"

dnl Use generic infrastructure for pthread detection (What a hell of a mess !)
gl_LOCK

AC_DEFINE([EFL_HAVE_THREADS], [1], [Define to mention that POSIX or Win32 threads are supported])

_efl_have_posix_threads="${gl_use_threads}"

dnl System specific CFLAGS
if test "x${_efl_have_posix_threads}" = "xyes"; then
   case "$host_os" in
      osf*) EFL_PTHREAD_CFLAGS="-D_REENTRANT" ;;
      aix* | freebsd*) EFL_PTHREAD_CFLAGS="-D_THREAD_SAFE" ;;
      solaris*) EFL_PTHREAD_CFLAGS="-D_REENTRANT" ;;
   esac
fi

dnl check if the compiler supports POSIX threads
if test "x${_efl_have_posix_threads}" = "xyes" ; then

   SAVE_LIBS=${LIBS}
   LIBS="${LIBS} ${LIBMULTITHREAD}"
   AC_LINK_IFELSE(
      [AC_LANG_PROGRAM([[
#include <pthread.h>
                       ]],
                       [[
pthread_barrier_t barrier;
pthread_barrier_init(&barrier, NULL, 1);
                       ]])],
      [efl_have_pthread_barrier="yes"],
      [efl_have_pthread_barrier="no"])
   AC_LINK_IFELSE(
      [AC_LANG_PROGRAM([[
#include <stdlib.h>
#include <pthread.h>
#include <sched.h>
                       ]],
                       [[
pthread_attr_setaffinity_np(NULL, 0, NULL);
                       ]])],
      [efl_have_setaffinity="yes"],
      [efl_have_setaffinity="no"])
   LIBS=${SAVE_LIBS}
fi

AC_MSG_CHECKING([which threads API is used])
if test "x${_efl_have_posix_threads}" = "xyes" ; then
   efl_have_threads="POSIX"
else
   if test "x${_efl_have_win32_threads}" = "xyes" ; then
      efl_have_threads="Windows"
      efl_have_pthread_barrier="no"
   else
      efl_have_threads="no"
      efl_have_pthread_barrier="no"
   fi
fi
AC_MSG_RESULT([${efl_have_threads}])

EFL_PTHREAD_LIBS="${LTLIBMULTITHREAD}"

AC_SUBST(EFL_PTHREAD_CFLAGS)
AC_SUBST(EFL_PTHREAD_LIBS)

dnl check if the compiler supports pthreads spinlock

efl_have_posix_threads_spinlock="no"

if test "x${_efl_have_posix_threads}" = "xyes" ; then
   SAVE_LIBS=${LIBS}
   LIBS="${LIBS} ${LIBMULTITHREAD}"
   AC_LINK_IFELSE(
      [AC_LANG_PROGRAM([[
#include <pthread.h>
#include <sched.h>
                       ]],
                       [[
pthread_spinlock_t lock;
int res;
res = pthread_spin_init(&lock, PTHREAD_PROCESS_PRIVATE);
sched_yield();
                       ]])],
      [efl_have_posix_threads_spinlock="yes"],
      [efl_have_posix_threads_spinlock="no"])
   LIBS=${SAVE_LIBS}

fi

AC_MSG_CHECKING([whether to build POSIX threads spinlock code])
AC_MSG_RESULT([${efl_have_posix_threads_spinlock}])

if test "x${efl_have_posix_threads_spinlock}" = "xyes" ; then
   AC_DEFINE([EFL_HAVE_POSIX_THREADS_SPINLOCK], [1], [Define to mention that POSIX threads spinlocks are supported])
fi


dnl checks if the compiler supports OSX spinlock

efl_have_osx_spinlock="no"

if test "x${_efl_have_posix_threads}" = "xyes" ; then
   AC_LINK_IFELSE(
      [AC_LANG_PROGRAM([[
#include <libkern/OSAtomic.h>
                       ]],
                       [[
OSSpinLock spin_lock = 0;
OSSpinLockTry(&spin_lock);
                       ]])],
      [efl_have_osx_spinlock="yes"],
      [efl_have_osx_spinlock="no"])
fi

AC_MSG_CHECKING([whether to build OSX spinlock code])
AC_MSG_RESULT([${efl_have_osx_spinlock}])

if test "x${efl_have_osx_spinlock}" = "xyes" ; then
   AC_DEFINE([EFL_HAVE_OSX_SPINLOCK], [1], [Define to mention that OSX spinlocks are supported])
fi



AS_IF([test "x$_efl_have_posix_threads" = "xyes" || test "x$_efl_have_win32_threads" = "xyes"],
   [$1],
   [m4_if([$2], [$2], [AC_MSG_ERROR([Threads are required.])])])


])