// Fiber test by Gynvael Coldwind of Vexillium
// http://gynvael.coldwind.pl
// http://vexillium.org
// mailto: gynvael@vexillium.org
//
// Note:
//  This code was created for educational purposes, so don't expect
//  fireworks.
//
// License (BSD):
//  Copyright (c) 2008, Gynvael Coldwind of Vexillium
//  All rights reserved.
//
//  Redistribution and use in source and binary forms, with or without
//  modification, are permitted provided that the following conditions are met:
//      * Redistributions of source code must retain the above copyright
//        notice, this list of conditions and the following disclaimer.
//      * Redistributions in binary form must reproduce the above copyright
//        notice, this list of conditions and the following disclaimer in the
//        documentation and/or other materials provided with the distribution.
//      * Neither the name of the Gynvael Coldwind nor Vexillium nor the
//        names of its contributors may be used to endorse or promote products
//        derived from this software without specific prior written permission.
//
//  THIS SOFTWARE IS PROVIDED BY Gynvael Coldwind ''AS IS'' AND ANY
//  EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
//  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
//  DISCLAIMED. IN NO EVENT SHALL Gynvael Coldwind BE LIABLE FOR ANY
//  DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
//  (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
//  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
//  ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
//  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
//  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#include <windows.h>
#include <stdio.h>

// Some constants
#define FIBER_COUNT 4

// Some variables
LPVOID FiberScheduler;
LPVOID Fibers[FIBER_COUNT];
int    FiberDone[FIBER_COUNT];

// Fiber Scheduler
void __stdcall MyScheduler(void *Param)
{
  int i;
  int CurrentFiber = -1;
  puts("S: start");
 
  while(1)
  {
    int DoneCount = 0;

    puts("S: schedule loop begining");

    // Check if all done
    for(i = 0; i < FIBER_COUNT; i++)
      DoneCount += FiberDone[i];

    if(DoneCount == FIBER_COUNT)
      break;

    // Switch to next av. fiber
    // There has to be at least one
    do
    {
      CurrentFiber++;
      if(CurrentFiber == FIBER_COUNT)
        CurrentFiber = 0;
    }
    while(FiberDone[CurrentFiber]);

    // Switch to it
    printf("S: schedule loop switching to fiber %i\n", CurrentFiber);
    SwitchToFiber(Fibers[CurrentFiber]);
    printf("S: schedule loop back from fiber %i\n", CurrentFiber);
  }

  puts("S: done"); 
}

// Fiber Worker
void __stdcall MyFiber(void* Param)
{
  int i;
  int FiberNr = (int)Param;
  printf("%i: start\n", FiberNr);

  for(i = 0; i < 2; i++)
  {
    printf("%i: in loop %i, before switch\n", FiberNr, i);
    SwitchToFiber(FiberScheduler);
    printf("%i: in loop %i, back from switch\n", FiberNr, i);
  }

  printf("%i: done\n", FiberNr); fflush(stdout);
  FiberDone[FiberNr] = 1;
  SwitchToFiber(FiberScheduler);
}

// Main function
int
main(void)
{
  // Create fibers
  int i;
  puts("M: creating scheduler fiber");
  FiberScheduler = CreateFiber(0, MyScheduler, NULL);
  puts("M: creating work fibers");
  for(i = 0; i < FIBER_COUNT; i++)
    Fibers[i] = CreateFiber(0, MyFiber, (void*)i);

  // Convert to fiber and launch scheduler
  puts("M: converting to fiber and switching to scheduler");
  ConvertThreadToFiber(NULL);
  SwitchToFiber(FiberScheduler);
  puts("M: done (the execution should never reach here)");

  return 0;
}