text: /*
   * -------------------------------------------------------------
   *
   * Module: sem_init.c
   *
   * Purpose:
   *	Semaphores aren't actually part of PThreads.
   *	They are defined by the POSIX Standard:
   *
   *		POSIX 1003.1-2001
   *
   * -------------------------------------------------------------
   *
   * --------------------------------------------------------------------------
   *
   *      Pthreads-win32 - POSIX Threads Library for Win32
   *      Copyright(C) 1998 John E. Bossom
   *      Copyright(C) 1999,2003 Pthreads-win32 contributors
   * 
   *      Contact Email: rpj@callisto.canberra.edu.au
   * 
   *      The current list of contributors is contained
   *      in the file CONTRIBUTORS included with the source
   *      code distribution. The list can also be seen at the
   *      following World Wide Web location:
   *      http://sources.redhat.com/pthreads-win32/contributors.html
   * 
   *      This library is free software; you can redistribute it and/or
   *      modify it under the terms of the GNU Lesser General Public
   *      License as published by the Free Software Foundation; either
   *      version 2 of the License, or (at your option) any later version.
   * 
   *      This library 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
   *      Lesser General Public License for more details.
   * 
   *      You should have received a copy of the GNU Lesser General Public
   *      License along with this library in the file COPYING.LIB;
   *      if not, write to the Free Software Foundation, Inc.,
   *      59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
   */
  
  #ifndef _UWIN
  #   include <process.h>
  #endif
  
  #include "pthread.h"
  #include "semaphore.h"
  #include "implement.h"
  
  int
  sem_init (sem_t * sem, int pshared, unsigned int value)
       /*
        * ------------------------------------------------------
        * DOCPUBLIC
        *      This function initializes a semaphore. The
        *      initial value of the semaphore is 'value'
        *
        * PARAMETERS
        *      sem
        * 	     pointer to an instance of sem_t
        *
        *      pshared
        * 	     if zero, this semaphore may only be shared between
        * 	     threads in the same process.
        * 	     if nonzero, the semaphore can be shared between
        * 	     processes
        *
        *      value
        * 	     initial value of the semaphore counter
        *
        * DESCRIPTION
        *      This function initializes a semaphore. The
        *      initial value of the semaphore is set to 'value'.
        *
        * RESULTS
        * 	     0		     successfully created semaphore,
        * 	     -1 	     failed, error in errno
        * ERRNO
        * 	     EINVAL	     'sem' is not a valid semaphore,
        * 	     ENOSPC	     a required resource has been exhausted,
        * 	     ENOSYS	     semaphores are not supported,
        * 	     EPERM	     the process lacks appropriate privilege
        *
        * ------------------------------------------------------
        */
  {
    int result = 0;
    sem_t s = NULL;
  
    if (pshared != 0)
      {
        /*
         * Creating a semaphore that can be shared between
         * processes
         */
        result = EPERM;
  
      }
    else
      {
  
        s = (sem_t) calloc (1, sizeof (*s));
  
        if (NULL == s)
  				{
  					result = ENOMEM;
  				}
  
  #ifdef NEED_SEM
  
        else
  				{
  					s->value = value;
  					s->event = CreateEvent (NULL,
  						PTW32_FALSE,	/* manual reset */
  						PTW32_FALSE,	/* initial state */
  						NULL);
  
  					if (0 == s->event)
  						{
  							result = ENOSPC;
  						}
  					else
  						{
  							if (value != 0)
  								{
  									SetEvent(s->event);
  								}
  
  							InitializeCriticalSection(&s->sem_lock_cs);
  						}
  				}
  
  #else /* NEED_SEM */
  
        s->sem = CreateSemaphore (NULL,			     /* Always NULL */
  				(long) value,		     /* Initial value */
  				(long) _POSIX_SEM_VALUE_MAX, /* Maximum value */
  				NULL);			     /* Name */
  			
        if (0 == s->sem)
  				{
  					result = ENOSPC;
  				}
  
  #endif /* NEED_SEM */
  
      }
  
    if (result != 0)
      {
        errno = result;
        return -1;
      }
  
    *sem = s;
  
    return 0;
  
  }				/* sem_init */
  