/*
 * private.c
 *
 * Description:
 * This translation unit implements routines which are private to
 * the implementation and may be used throughout it.
 */

#include <windows.h>
#include <process.h>
#include "pthread.h"
#include "implement.h"

int
_pthread_getthreadindex(pthread_t thread)
{
  /* The hash table works as follows:
     hash into the table,
     if the thread in this slot doesn't match then start single
     stepping from there until we find it, or we hit an empty slot, or
     we end up where we started from.

     The scheme should have these characteristics:
     - if the thread handle is a sequence number then the hash will
       succeed first time every time,
     - if the thread handle is a pseudo randomish value (eg. a pointer)
       then the hash should succeed first time most times.
   */
  int t = _PTHREAD_HASH_INDEX(thread);
  int it = t; /* Remember where we started from. */

  while ((_pthread_threads_table[t])->thread != thread) {
    t++;

    if (t == PTHREAD_THREADS_MAX)
      t = 0; /* Wrap around to the first slot */

    if ((_pthread_threads_table[t])->thread == NULL || t == it)
      return -1; /* Failed to find the thread */
  }
  return t;
}