/*
Copyright (C) 1999-2006 Id Software, Inc. and contributors.
For a list of contributors, see the accompanying CONTRIBUTORS file.

This file is part of GtkRadiant.

GtkRadiant is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

GtkRadiant is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with GtkRadiant; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
*/

#ifndef WIN32
// The below define is necessary to use
// pthreads extensions like pthread_mutexattr_settype
#define _GNU_SOURCE
#include <pthread.h>
#endif

#include "cmdlib.h"
#include "mathlib.h"
#include "inout.h"
#include "q2_threads.h"

#define	MAX_THREADS	64

int		dispatch;
int		workcount;
int		oldf;
qboolean		pacifier;

qboolean	threaded;

/*
=============
GetThreadWork

=============
*/
int	GetThreadWork (void)
{
	int	r;
	int	f;

	ThreadLock ();

	if (dispatch == workcount)
	{
		ThreadUnlock ();
		return -1;
	}

	f = 10*dispatch / workcount;
	if (f != oldf)
	{
		oldf = f;
		if (pacifier)
		{
			Sys_Printf ("%i...", f);
			fflush( stdout );	/* ydnar */
		}
	}

	r = dispatch;
	dispatch++;
	ThreadUnlock ();

	return r;
}


void (*workfunction) (int);

void ThreadWorkerFunction (int threadnum)
{
	int		work;

	while (1)
	{
		work = GetThreadWork ();
		if (work == -1)
			break;
		//Sys_FPrintf( SYS_VRB,"thread %i, work %i\n", threadnum, work);
		workfunction(work);
	}
}

void RunThreadsOnIndividual (int workcnt, qboolean showpacifier, void(*func)(int))
{
	if (numthreads == -1)
		ThreadSetDefault ();
	workfunction = func;
  RunThreadsOn (workcnt, showpacifier, ThreadWorkerFunction);
}


/*
===================================================================

WIN32

===================================================================
*/
#ifdef WIN32

#define	USED

#include <windows.h>

// Setting default Threads to 1
int		numthreads = 1;
CRITICAL_SECTION		crit;
static int enter;

void ThreadSetDefault (void)
{
	SYSTEM_INFO info;

	if (numthreads == -1)	// not set manually
	{
		GetSystemInfo (&info);
		numthreads = info.dwNumberOfProcessors;
		if (numthreads < 1 || numthreads > 32)
			numthreads = 1;
	}

	Sys_Printf ("%i threads\n", numthreads);
}


void ThreadLock (void)
{
	if (!threaded)
		return;
	EnterCriticalSection (&crit);
	if (enter)
		Error ("Recursive ThreadLock\n");
	enter = 1;
}

void ThreadUnlock (void)
{
	if (!threaded)
		return;
	if (!enter)
		Error ("ThreadUnlock without lock\n");
	enter = 0;
	LeaveCriticalSection (&crit);
}

/*
=============
RunThreadsOn
=============
*/
void RunThreadsOn (int workcnt, qboolean showpacifier, void(*func)(int))
{
	int		threadid[MAX_THREADS];
	HANDLE	threadhandle[MAX_THREADS];
	int		i;
	int		start, end;

	start = I_FloatTime ();
	dispatch = 0;
	workcount = workcnt;
	oldf = -1;
	pacifier = showpacifier;
	threaded = true;

	//
	// run threads in parallel
	//
	InitializeCriticalSection (&crit);

	if (numthreads == 1)
	{	// use same thread
		func (0);
	}
	else
	{
		for (i=0 ; i<numthreads ; i++)
		{
			threadhandle[i] = CreateThread(
			   NULL,	// LPSECURITY_ATTRIBUTES lpsa,
			   //0,		// DWORD cbStack,

				/* ydnar: cranking stack size to eliminate radiosity crash with 1MB stack on win32 */
				(4096 * 1024),

			   (LPTHREAD_START_ROUTINE)func,	// LPTHREAD_START_ROUTINE lpStartAddr,
			   (LPVOID)i,	// LPVOID lpvThreadParm,
			   0,			//   DWORD fdwCreate,
			   &threadid[i]);
		}

		for (i=0 ; i<numthreads ; i++)
			WaitForSingleObject (threadhandle[i], INFINITE);
	}
	DeleteCriticalSection (&crit);

	threaded = false;
	end = I_FloatTime ();
	if (pacifier)
		Sys_Printf (" (%i)\n", end-start);
}


#endif

/*
===================================================================

OSF1

===================================================================
*/

#ifdef __osf__
#define	USED

int		numthreads = 4;

void ThreadSetDefault (void)
{
	if (numthreads == -1)	// not set manually
	{
		numthreads = 4;
	}
}


#include <pthread.h>

pthread_mutex_t	*my_mutex;

void ThreadLock (void)
{
	if (my_mutex)
		pthread_mutex_lock (my_mutex);
}

void ThreadUnlock (void)
{
	if (my_mutex)
		pthread_mutex_unlock (my_mutex);
}


/*
=============
RunThreadsOn
=============
*/
void RunThreadsOn (int workcnt, qboolean showpacifier, void(*func)(int))
{
	int		i;
	pthread_t	work_threads[MAX_THREADS];
	pthread_addr_t	status;
	pthread_attr_t	attrib;
	pthread_mutexattr_t	mattrib;
	int		start, end;

	start = I_FloatTime ();
	dispatch = 0;
	workcount = workcnt;
	oldf = -1;
	pacifier = showpacifier;
	threaded = true;

	if (pacifier)
		setbuf (stdout, NULL);

	if (!my_mutex)
	{
		my_mutex = safe_malloc (sizeof(*my_mutex));
		if (pthread_mutexattr_create (&mattrib) == -1)
			Error ("pthread_mutex_attr_create failed");
		if (pthread_mutexattr_setkind_np (&mattrib, MUTEX_FAST_NP) == -1)
			Error ("pthread_mutexattr_setkind_np failed");
		if (pthread_mutex_init (my_mutex, mattrib) == -1)
			Error ("pthread_mutex_init failed");
	}

	if (pthread_attr_create (&attrib) == -1)
		Error ("pthread_attr_create failed");
	if (pthread_attr_setstacksize (&attrib, 0x100000) == -1)
		Error ("pthread_attr_setstacksize failed");
	
	for (i=0 ; i<numthreads ; i++)
	{
  		if (pthread_create(&work_threads[i], attrib
		, (pthread_startroutine_t)func, (pthread_addr_t)i) == -1)
			Error ("pthread_create failed");
	}
		
	for (i=0 ; i<numthreads ; i++)
	{
		if (pthread_join (work_threads[i], &status) == -1)
			Error ("pthread_join failed");
	}

	threaded = false;

	end = I_FloatTime ();
	if (pacifier)
		Sys_Printf (" (%i)\n", end-start);
}


#endif

/*
===================================================================

IRIX

===================================================================
*/

#ifdef _MIPS_ISA 
#define	USED

#include <task.h>
#include <abi_mutex.h>
#include <sys/types.h>
#include <sys/prctl.h>


int		numthreads = -1;
abilock_t		lck;

void ThreadSetDefault (void)
{
	if (numthreads == -1)
		numthreads = prctl(PR_MAXPPROCS);
	Sys_Printf ("%i threads\n", numthreads);
	usconfig (CONF_INITUSERS, numthreads);
}


void ThreadLock (void)
{
	spin_lock (&lck);
}

void ThreadUnlock (void)
{
	release_lock (&lck);
}


/*
=============
RunThreadsOn
=============
*/
void RunThreadsOn (int workcnt, qboolean showpacifier, void(*func)(int))
{
	int		i;
	int		pid[MAX_THREADS];
	int		start, end;

	start = I_FloatTime ();
	dispatch = 0;
	workcount = workcnt;
	oldf = -1;
	pacifier = showpacifier;
	threaded = true;

	if (pacifier)
		setbuf (stdout, NULL);

	init_lock (&lck);

	for (i=0 ; i<numthreads-1 ; i++)
	{
		pid[i] = sprocsp ( (void (*)(void *, size_t))func, PR_SALL, (void *)i
			, NULL, 0x200000);		// 2 meg stacks
		if (pid[i] == -1)
		{
			perror ("sproc");
			Error ("sproc failed");
		}
	}
		
	func(i);
			
	for (i=0 ; i<numthreads-1 ; i++)
		wait (NULL);

	threaded = false;

	end = I_FloatTime ();
	if (pacifier)
		Sys_Printf (" (%i)\n", end-start);
}


#endif


/*
=======================================================================

  Linux pthreads

=======================================================================
*/

#if defined( __linux__ ) || defined( __APPLE__ )
#define USED

// Setting default Threads to 1
int		numthreads = 1;

void ThreadSetDefault (void)
{
	if (numthreads == -1)	// not set manually
	{
    /* default to one thread, only multi-thread when specifically told to */
		numthreads = 1;
	}
  if(numthreads > 1)
    Sys_Printf("threads: %d\n", numthreads);
}

#include <pthread.h>

typedef struct pt_mutex_s
{
  pthread_t       *owner;
  pthread_mutex_t a_mutex;
  pthread_cond_t  cond;
  unsigned int    lock;
} pt_mutex_t;

pt_mutex_t global_lock;

void ThreadLock(void)
{
  pt_mutex_t *pt_mutex = &global_lock;

  if(!threaded)
    return;

  pthread_mutex_lock(&pt_mutex->a_mutex);
  if(pthread_equal(pthread_self(), (pthread_t)&pt_mutex->owner)) 
    pt_mutex->lock++;
  else
  {
    if((!pt_mutex->owner) && (pt_mutex->lock == 0))
    {
      pt_mutex->owner = (pthread_t *)pthread_self();
      pt_mutex->lock  = 1;
    }
    else
    {
      while(1)
      {
        pthread_cond_wait(&pt_mutex->cond, &pt_mutex->a_mutex);
        if((!pt_mutex->owner) && (pt_mutex->lock == 0))
        {
          pt_mutex->owner = (pthread_t *)pthread_self();
          pt_mutex->lock  = 1;
          break;
        }
      }
    }
  }
  pthread_mutex_unlock(&pt_mutex->a_mutex);
}

void ThreadUnlock(void)
{
  pt_mutex_t *pt_mutex = &global_lock;
  
  if(!threaded)
    return;

  pthread_mutex_lock(&pt_mutex->a_mutex);
  pt_mutex->lock--;
  
  if(pt_mutex->lock == 0)
  {
    pt_mutex->owner = NULL;
    pthread_cond_signal(&pt_mutex->cond);
  }
  
  pthread_mutex_unlock(&pt_mutex->a_mutex);
}

void recursive_mutex_init(pthread_mutexattr_t attribs)
{
  pt_mutex_t *pt_mutex = &global_lock;
  
  pt_mutex->owner = NULL;
  if(pthread_mutex_init(&pt_mutex->a_mutex, &attribs) != 0)
    Error("pthread_mutex_init failed\n");
  if(pthread_cond_init(&pt_mutex->cond, NULL) != 0)
    Error("pthread_cond_init failed\n");
  
  pt_mutex->lock = 0;
}

/*
=============
RunThreadsOn
=============
*/
void RunThreadsOn (int workcnt, qboolean showpacifier, void(*func)(int))
{
  pthread_mutexattr_t         mattrib;
  pthread_t work_threads[MAX_THREADS];
  
  int	  start, end;
  int   i=0, status=0;
  
  start     = I_FloatTime ();
  pacifier  = showpacifier;
  
  dispatch  = 0;
  oldf      = -1;
  workcount = workcnt;
  
  if(numthreads == 1)
    func(0);
  else
  {    
    threaded  = true;
      
    if(pacifier)
      setbuf(stdout, NULL);

    if(pthread_mutexattr_init(&mattrib) != 0)
      Error("pthread_mutexattr_init failed");
#if __GLIBC_MINOR__ == 1
    if (pthread_mutexattr_settype(&mattrib, PTHREAD_MUTEX_FAST_NP) != 0)
#else
    if (pthread_mutexattr_settype(&mattrib, PTHREAD_MUTEX_ADAPTIVE_NP) != 0)
#endif
      Error ("pthread_mutexattr_settype failed");
    recursive_mutex_init(mattrib);

    for (i=0 ; i<numthreads ; i++)
    {
      /* Default pthread attributes: joinable & non-realtime scheduling */
      if(pthread_create(&work_threads[i], NULL, (void*)func, (void*)i) != 0)
        Error("pthread_create failed");
    }
    for (i=0 ; i<numthreads ; i++)
    {
      if(pthread_join(work_threads[i], (void **)&status) != 0)
        Error("pthread_join failed");
    }
    pthread_mutexattr_destroy(&mattrib);
    threaded = false;
  }
  
  end = I_FloatTime ();
  if (pacifier)
    Sys_Printf (" (%i)\n", end-start);
}
#endif // ifdef __linux__


/*
=======================================================================

  SINGLE THREAD

=======================================================================
*/

#ifndef USED

int		numthreads = 1;

void ThreadSetDefault (void)
{
	numthreads = 1;
}

void ThreadLock (void)
{
}

void ThreadUnlock (void)
{
}

/*
=============
RunThreadsOn
=============
*/
void RunThreadsOn (int workcnt, qboolean showpacifier, void(*func)(int))
{
	int		i;
	int		start, end;

	dispatch = 0;
	workcount = workcnt;
	oldf = -1;
	pacifier = showpacifier;
	start = I_FloatTime (); 
	func(0);

	end = I_FloatTime ();
	if (pacifier)
		Sys_Printf (" (%i)\n", end-start);
}

#endif