RetroArch/deps/pthreads/pthread_attr.c

/*
 * pthread_attr.c
 *
 * Description:
 * This translation unit implements operations on thread attribute objects.
 *
 * --------------------------------------------------------------------------
 *
 *      Pthreads-embedded (PTE) - POSIX Threads Library for embedded systems
 *      Copyright(C) 2008 Jason Schmidlapp
 *
 *      Contact Email: jschmidlapp@users.sourceforge.net
 *
 *
 *      Based upon Pthreads-win32 - POSIX Threads Library for Win32
 *      Copyright(C) 1998 John E. Bossom
 *      Copyright(C) 1999,2005 Pthreads-win32 contributors
 *
 *      Contact Email: rpj@callisto.canberra.edu.au
 *
 *      The original list of contributors to the Pthreads-win32 project
 *      is contained in the file CONTRIBUTORS.ptw32 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
 */

#include <stdlib.h>
#include <string.h>

#include "pthread.h"
#include "implement.h"
#include "sched.h"

int
pthread_attr_destroy (pthread_attr_t * attr)
/*
 * ------------------------------------------------------
 * DOCPUBLIC
 *      Destroys a thread attributes object.
 *
 * PARAMETERS
 *      attr
 *              pointer to an instance of pthread_attr_t
 *
 *
 * DESCRIPTION
 *      Destroys a thread attributes object.
 *
 *      NOTES:
 *              1)      Does not affect threads created with 'attr'.
 *
 * RESULTS
 *              0               successfully destroyed attr,
 *              EINVAL          'attr' is invalid.
 *
 * ------------------------------------------------------
 */
{
   if (pte_is_attr (attr) != 0)
      return EINVAL;

   /*
    * Set the attribute object to a specific invalid value.
    */
   (*attr)->valid = 0;
   free (*attr);
   *attr = NULL;

   return 0;
}

int pthread_attr_getdetachstate (const pthread_attr_t * attr, int *detachstate)
   /*
    * ------------------------------------------------------
    * DOCPUBLIC
    *      This function determines whether threads created with
    *      'attr' will run detached.
    *
    * PARAMETERS
    *      attr
    *              pointer to an instance of pthread_attr_t
    *
    *      detachstate
    *              pointer to an integer into which is returned one
    *              of:
    *
    *              PTHREAD_CREATE_JOINABLE
    *                              Thread ID is valid, must be joined
    *
    *              PTHREAD_CREATE_DETACHED
    *                              Thread ID is invalid, cannot be joined,
    *                              canceled, or modified
    *
    *
    * DESCRIPTION
    *      This function determines whether threads created with
    *      'attr' will run detached.
    *
    *      NOTES:
    *              1)      You cannot join or cancel detached threads.
    *
    * RESULTS
    *              0               successfully retrieved detach state,
    *              EINVAL          'attr' is invalid
    *
    * ------------------------------------------------------
    */
{
   if (pte_is_attr (attr) != 0 || detachstate == NULL)
   {
      *detachstate = PTHREAD_CREATE_DETACHED;
      return EINVAL;
   }

   *detachstate = (*attr)->detachstate;
   return 0;
}

int pthread_attr_getinheritsched (pthread_attr_t * attr, int *inheritsched)
{
   if (pte_is_attr (attr) != 0 || inheritsched == NULL)
      return EINVAL;

   *inheritsched = (*attr)->inheritsched;
   return 0;
}

int pthread_attr_getschedparam (const pthread_attr_t * attr,
      struct sched_param *param)
{
   if (pte_is_attr (attr) != 0 || param == NULL)
      return EINVAL;

   memcpy (param, &(*attr)->param, sizeof (*param));
   return 0;
}

int pthread_attr_getschedpolicy (pthread_attr_t * attr, int *policy)
{
   if (pte_is_attr (attr) != 0 || policy == NULL)
      return EINVAL;

   /*
    * Validate the policy arg.
    * Check that a policy constant wasn't passed rather than &policy.
    */
   if (policy <= (int *) SCHED_MAX)
      return EINVAL;

   *policy = SCHED_OTHER;

   return 0;
}

int pthread_attr_getscope (const pthread_attr_t * attr, int *contentionscope)
{
#ifdef _POSIX_THREAD_PRIORITY_SCHEDULING
   *contentionscope = (*attr)->contentionscope;
   return 0;
#else
   return ENOSYS;
#endif
}

int pthread_attr_getstackaddr (const pthread_attr_t * attr, void **stackaddr)
   /*
    * ------------------------------------------------------
    * DOCPUBLIC
    *      This function determines the address of the stack
    *      on which threads created with 'attr' will run.
    *
    * PARAMETERS
    *      attr
    *              pointer to an instance of pthread_attr_t
    *
    *      stackaddr
    *              pointer into which is returned the stack address.
    *
    *
    * DESCRIPTION
    *      This function determines the address of the stack
    *      on which threads created with 'attr' will run.
    *
    *      NOTES:
    *              1)      Function supported only if this macro is
    *                      defined:
    *
    *                              _POSIX_THREAD_ATTR_STACKADDR
    *
    *              2)      Create only one thread for each stack
    *                      address..
    *
    * RESULTS
    *              0               successfully retreived stack address,
    *              EINVAL          'attr' is invalid
    *              ENOSYS          function not supported
    *
    * ------------------------------------------------------
    */
{
#if defined( _POSIX_THREAD_ATTR_STACKADDR )

   if (pte_is_attr (attr) != 0)
      return EINVAL;

   *stackaddr = (*attr)->stackaddr;
   return 0;

#else

   return ENOSYS;

#endif /* _POSIX_THREAD_ATTR_STACKADDR */
}

int
pthread_attr_getstacksize (const pthread_attr_t * attr, size_t * stacksize)
/*
 * ------------------------------------------------------
 * DOCPUBLIC
 *      This function determines the size of the stack on
 *      which threads created with 'attr' will run.
 *
 * PARAMETERS
 *      attr
 *              pointer to an instance of pthread_attr_t
 *
 *      stacksize
 *              pointer to size_t into which is returned the
 *              stack size, in bytes.
 *
 *
 * DESCRIPTION
 *      This function determines the size of the stack on
 *      which threads created with 'attr' will run.
 *
 *      NOTES:
 *              1)      Function supported only if this macro is
 *                      defined:
 *
 *                              _POSIX_THREAD_ATTR_STACKSIZE
 *
 *              2)      Use on newly created attributes object to
 *                      find the default stack size.
 *
 * RESULTS
 *              0               successfully retrieved stack size,
 *              EINVAL          'attr' is invalid
 *              ENOSYS          function not supported
 *
 * ------------------------------------------------------
 */
{
#ifdef _POSIX_THREAD_ATTR_STACKSIZE

   if (pte_is_attr (attr) != 0)
      return EINVAL;

   /* Everything is okay. */
   *stacksize = (*attr)->stacksize;
   return 0;

#else

   return ENOSYS;

#endif /* _POSIX_THREAD_ATTR_STACKSIZE */
}

int pthread_attr_init (pthread_attr_t * attr)
/*
 * ------------------------------------------------------
 * DOCPUBLIC
 *      Initializes a thread attributes object with default
 *      attributes.
 *
 * PARAMETERS
 *      attr
 *              pointer to an instance of pthread_attr_t
 *
 *
 * DESCRIPTION
 *      Initializes a thread attributes object with default
 *      attributes.
 *
 *      NOTES:
 *              1)      Used to define thread attributes
 *
 * RESULTS
 *              0               successfully initialized attr,
 *              ENOMEM          insufficient memory for attr.
 *
 * ------------------------------------------------------
 */
{
   pthread_attr_t attr_result;

   /* This is disallowed. */
   if (attr == NULL)
      return EINVAL;

   attr_result = (pthread_attr_t) malloc (sizeof (*attr_result));

   if (attr_result == NULL)
      return ENOMEM;

#ifdef _POSIX_THREAD_ATTR_STACKSIZE
   /*
    * Default to zero size?
    */
   attr_result->stacksize = 0;
#endif

#ifdef _POSIX_THREAD_ATTR_STACKADDR
   /* FIXME: Set this to something sensible when we support it. */
   attr_result->stackaddr = NULL;
#endif

   attr_result->detachstate = PTHREAD_CREATE_JOINABLE;

   /*
    * Win32 sets new threads to THREAD_PRIORITY_NORMAL and
    * not to that of the parent thread. We choose to default to
    * this arrangement.
    */
   attr_result->param.sched_priority = pte_osThreadGetDefaultPriority();
   attr_result->inheritsched = PTHREAD_EXPLICIT_SCHED;
   attr_result->contentionscope = PTHREAD_SCOPE_SYSTEM;

   attr_result->valid = PTE_ATTR_VALID;

   *attr = attr_result;

   return 0;
}

int pthread_attr_setdetachstate (pthread_attr_t * attr, int detachstate)
   /*
    * ------------------------------------------------------
    * DOCPUBLIC
    *      This function specifies whether threads created with
    *      'attr' will run detached.
    *
    * PARAMETERS
    *      attr
    *              pointer to an instance of pthread_attr_t
    *
    *      detachstate
    *              an integer containing one of:
    *
    *              PTHREAD_CREATE_JOINABLE
    *                              Thread ID is valid, must be joined
    *
    *              PTHREAD_CREATE_DETACHED
    *                              Thread ID is invalid, cannot be joined,
    *                              canceled, or modified
    *
    *
    * DESCRIPTION
    *      This function specifies whether threads created with
    *      'attr' will run detached.
    *
    *      NOTES:
    *              1)      You cannot join or cancel detached threads.
    *
    * RESULTS
    *              0               successfully set detach state,
    *              EINVAL          'attr' or 'detachstate' is invalid
    *
    * ------------------------------------------------------
    */
{
   if (pte_is_attr (attr) != 0)
      return EINVAL;

   if (detachstate != PTHREAD_CREATE_JOINABLE &&
         detachstate != PTHREAD_CREATE_DETACHED)
      return EINVAL;

   (*attr)->detachstate = detachstate;
   return 0;
}

int pthread_attr_setinheritsched (pthread_attr_t * attr, int inheritsched)
{
   if (pte_is_attr (attr) != 0)
      return EINVAL;

   if (PTHREAD_INHERIT_SCHED != inheritsched
         && PTHREAD_EXPLICIT_SCHED != inheritsched)
      return EINVAL;

   (*attr)->inheritsched = inheritsched;
   return 0;
}

int pthread_attr_setschedparam (pthread_attr_t * attr,
                            const struct sched_param *param)
{
   int priority;

   if (pte_is_attr (attr) != 0 || param == NULL)
      return EINVAL;

   priority = param->sched_priority;

   /* Validate priority level. */
   if (priority < sched_get_priority_min (SCHED_OTHER) ||
         priority > sched_get_priority_max (SCHED_OTHER))
   {
      return EINVAL;
   }

   memcpy (&(*attr)->param, param, sizeof (*param));
   return 0;
}

int pthread_attr_setschedpolicy (pthread_attr_t * attr, int policy)
{
   if (pte_is_attr (attr) != 0)
      return EINVAL;

   if (policy != SCHED_OTHER)
      return ENOTSUP;

   return 0;
}

int pthread_attr_setscope (pthread_attr_t * attr, int contentionscope)
{
#ifdef _POSIX_THREAD_PRIORITY_SCHEDULING
   switch (contentionscope)
   {
      case PTHREAD_SCOPE_SYSTEM:
         (*attr)->contentionscope = contentionscope;
         return 0;
      case PTHREAD_SCOPE_PROCESS:
         return ENOTSUP;
      default:
         return EINVAL;
   }
#else
   return ENOSYS;
#endif
}

int pthread_attr_setstackaddr (pthread_attr_t * attr, void *stackaddr)
/*
 * ------------------------------------------------------
 * DOCPUBLIC
 *      Threads created with 'attr' will run on the stack
 *      starting at 'stackaddr'.
 *      Stack must be at least PTHREAD_STACK_MIN bytes.
 *
 * PARAMETERS
 *      attr
 *              pointer to an instance of pthread_attr_t
 *
 *      stacksize
 *              stack size, in bytes.
 *
 *
 * DESCRIPTION
 *      Threads created with 'attr' will run on the stack
 *      starting at 'stackaddr'.
 *      Stack must be at least PTHREAD_STACK_MIN bytes.
 *
 *      NOTES:
 *              1)      Function supported only if this macro is
 *                      defined:
 *
 *                              _POSIX_THREAD_ATTR_STACKADDR
 *
 *              2)      Create only one thread for each stack
 *                      address..
 *
 *              3)      Ensure that stackaddr is aligned.
 *
 * RESULTS
 *              0               successfully set stack address,
 *              EINVAL          'attr' is invalid
 *              ENOSYS          function not supported
 *
 * ------------------------------------------------------
 */
{
#if defined( _POSIX_THREAD_ATTR_STACKADDR )

   if (pte_is_attr (attr) != 0)
      return EINVAL;

   (*attr)->stackaddr = stackaddr;
   return 0;

#else

   return ENOSYS;

#endif /* _POSIX_THREAD_ATTR_STACKADDR */
}

int pthread_attr_setstacksize (pthread_attr_t * attr, size_t stacksize)
   /*
    * ------------------------------------------------------
    * DOCPUBLIC
    *      This function specifies the size of the stack on
    *      which threads created with 'attr' will run.
    *
    * PARAMETERS
    *      attr
    *              pointer to an instance of pthread_attr_t
    *
    *      stacksize
    *              stack size, in bytes.
    *
    *
    * DESCRIPTION
    *      This function specifies the size of the stack on
    *      which threads created with 'attr' will run.
    *
    *      NOTES:
    *              1)      Function supported only if this macro is
    *                      defined:
    *
    *                              _POSIX_THREAD_ATTR_STACKSIZE
    *
    *              2)      Find the default first (using
    *                      pthread_attr_getstacksize), then increase
    *                      by multiplying.
    *
    *              3)      Only use if thread needs more than the
    *                      default.
    *
    * RESULTS
    *              0               successfully set stack size,
    *              EINVAL          'attr' is invalid or stacksize too
    *                              small or too big.
    *              ENOSYS          function not supported
    *
    * ------------------------------------------------------
    */
{
#ifdef _POSIX_THREAD_ATTR_STACKSIZE

#if PTHREAD_STACK_MIN > 0

   /*  Verify that the stack size is within range. */
   if (stacksize < PTHREAD_STACK_MIN)
      return EINVAL;

#endif

   if (pte_is_attr (attr) != 0)
      return EINVAL;

   /* Everything is okay. */
   (*attr)->stacksize = stacksize;
   return 0;

#else

   return ENOSYS;

#endif /* _POSIX_THREAD_ATTR_STACKSIZE */
}