/* threadex.c */

/* This version is used to test Dekkers's algorithm for N threads */

/* To compile (on a Solaris == SunOS 5.x machine )        */
/*    cc threadex.c -lthread                              */
/* To run                                                 */
/*    a.out 1000000                                       */

#include <stdio.h>
#include <thread.h>
#include <synch.h>

#define MAX_THREADS 16         /* Maximum possible number of threads  */
#define NUM_THREADS  8         /* Number of threads to us in this run */

int stack[MAX_THREADS][4096];  /* Stacks for the new threads             */
thread_t td[MAX_THREADS];      /* Thread descriptors for the new threads */

volatile int shared = 0;       /* The shared variable being updated */
int loopcount = 100000;        /* Default value for increment count */

#if 1

void dek_lock(
int tid)
{}

void dek_unlock(
int tid)
{}

#endif

/* We will run instances of this function as separate threads */

void xthread(
int  id)       /* Logical thread id.. values are 0, 1, 2,... */
{
   int i;
   int local;

   printf("Made it in %d \n", id);

   for (i = 0; i < loopcount; i++)
   {
      dek_lock(id);

      local = shared;
      local += 1;
      thr_yield();
      shared = local;

      dek_unlock(id);
   }
   thr_exit((void *)0);
}

void main(
int argc,
char **argv)
{
   int tid;
   int pri;
   int stat;
   thread_t gone;    /* Place to return status of exiting threads */
   int tstatus;

/* Override loop count if user supplied one */

   if (argc > 1)
      sscanf(argv[1], "%d", &loopcount);

/* Test to see if thread support is alive and well */

   stat = thr_setconcurrency(NUM_THREADS);
   printf("Set Concurrency Stat = %d \n", stat);
   stat = thr_getconcurrency();
   printf("Concurrency = %d \n", stat);

/* Create the threads */

   stat = thr_min_stack();
   printf("Min stack size = %d \n", stat);

   for (tid = 0; tid < NUM_THREADS; tid++)
   {
      stat = thr_create(stack[tid], sizeof(stack[0]),
                                 xthread, tid, THR_NEW_LWP, &td[tid]);
      printf("Create status = %d \n", tid);
   }

/* Wait for all  to terminate */

   for (tid = 0; tid < NUM_THREADS; tid++)
   {
      stat = thr_join(td[tid], &gone, &tstatus);
      printf("Thread %d done \n", tid);
   }

   printf("Made it out \n");
   printf("Value of shared is %d \n",  shared);
}