newlib-cygwin/winsup/testsuite/winsup.api/pthread/cancel3.c

/*
 * File: cancel3.c
 *
 * Test Synopsis: Test asynchronous cancelation.
 *
 * Test Method (Validation or Falsification):
 * - 
 *
 * Requirements Tested:
 * -
 *
 * Features Tested:
 * - 
 *
 * Cases Tested:
 * - 
 *
 * Description:
 * - 
 *
 * Environment:
 * - 
 *
 * Input:
 * - None.
 *
 * Output:
 * - File name, Line number, and failed expression on failure.
 * - No output on success.
 *
 * Assumptions:
 * - have working pthread_create, pthread_self, pthread_mutex_lock/unlock
 *   pthread_testcancel, pthread_cancel, pthread_join
 *
 * Pass Criteria:
 * - Process returns zero exit status.
 *
 * Fail Criteria:
 * - Process returns non-zero exit status.
 */

#include "test.h"

/*
 * Create NUMTHREADS threads in addition to the Main thread.
 */
enum {
  NUMTHREADS = 10
};

typedef struct bag_t_ bag_t;
struct bag_t_ {
  int threadnum;
  int started;
  /* Add more per-thread state variables here */
  int count;
};

static bag_t threadbag[NUMTHREADS + 1];

void *
mythread(void * arg)
{
  void* result = (void*)((int)(size_t)PTHREAD_CANCELED + 1);
  bag_t * bag = (bag_t *) arg;

  assert(bag == &threadbag[bag->threadnum]);
  assert(bag->started == 0);
  bag->started = 1;

  /* Set to known state and type */

  assert(pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, NULL) == 0);

  assert(pthread_setcanceltype(PTHREAD_CANCEL_ASYNCHRONOUS, NULL) == 0);

  /*
   * We wait up to 30 seconds for a cancelation to be applied to us.
   */
  for (bag->count = 0; bag->count < 30; bag->count++)
    {
      /* Busy wait to avoid Sleep(), since we can't asynchronous cancel inside a
	 kernel function. (This is still somewhat fragile as if the async cancel
	 can fail if it happens to occur while we're inside the kernel function
	 that time() calls...)  */
      time_t start = time(NULL);
      while ((time(NULL) - start) < 1)
	{
	  int i;
	  for (i = 0; i < 1E7; i++)
	    __asm__ volatile ("pause":::);
	}
    }

  /* Notice if asynchronous cancel got deferred */
  pthread_testcancel();

  return result;
}

int
main()
{
  int failed = 0;
  int i;
  pthread_t t[NUMTHREADS + 1];
  int ran_to_completion = 0;

  assert((t[0] = pthread_self()) != NULL);

  for (i = 1; i <= NUMTHREADS; i++)
    {
      threadbag[i].started = 0;
      threadbag[i].threadnum = i;
      assert(pthread_create(&t[i], NULL, mythread, (void *) &threadbag[i]) == 0);
    }

  /*
   * Code to control or munipulate child threads should probably go here.
   */
  Sleep(500);

  for (i = 1; i <= NUMTHREADS; i++)
    {
      assert(pthread_cancel(t[i]) == 0);
    }

  /*
   * Give threads time to run.
   */
  Sleep(NUMTHREADS * 100);

  /*
   * Standard check that all threads started.
   */
  for (i = 1; i <= NUMTHREADS; i++)
    { 
      if (!threadbag[i].started)
	{
	  failed |= !threadbag[i].started;
	  fprintf(stderr, "Thread %d: started %d\n", i, threadbag[i].started);
	}
    }

  assert(!failed);

  /*
   * Check any results here. Set "failed" and only print output on failure.
   */
  failed = 0;
  for (i = 1; i <= NUMTHREADS; i++)
    {
      int fail = 0;
      void *result = 0;

      /*
       * The thread does not contain any cancelation points, so
       * a return value of PTHREAD_CANCELED confirms that async
       * cancelation succeeded.
       */
      assert(pthread_join(t[i], &result) == 0);

      fail = (result != PTHREAD_CANCELED);

      if (fail)
	{
	  fprintf(stderr, "Thread %d: started %d: count %d: result %d \n",
		  i,
		  threadbag[i].started,
		  threadbag[i].count,
		  result);
	}

      if (threadbag[i].count >= 30)
	ran_to_completion++;

      failed = (failed || fail);
    }

  if (ran_to_completion >= 10)
    {
      fprintf(stderr, "All threads ran to completion, async cancellation never happened\n");
      failed = 1;
    }

  assert(!failed);

  /*
   * Success.
   */
  return 0;
}