sched.h

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/*
 * Module: sched.h
 *
 * Purpose:
 * Provides an implementation of POSIX realtime extensions
 * as defined in
 *
 * POSIX 1003.1b-1993 (POSIX.1b)
 *
 * --------------------------------------------------------------------------
 *
 * Pthreads-embedded (PTE) - POSIX Threads Library for embedded systems
 * Copyright(C) 2008 Jason Schmidlapp
 *
 * Contact Email: [email protected]
 *
 *
 * Pthreads-embedded (PTE) - POSIX Threads Library for embedded systems
 * Copyright(C) 2008 Jason Schmidlapp
 *
 * Contact Email: [email protected]
 *
 *
 * Based upon Pthreads-win32 - POSIX Threads Library for Win32
 * Copyright(C) 1998 John E. Bossom
 * Copyright(C) 1999,2005 Pthreads-win32 contributors
 *
 * Contact Email: [email protected]
 *
 * 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
 */
#ifndef _SCHED_H
#define _SCHED_H

#include <pte_types.h>

#undef PTE_LEVEL

#if defined(_POSIX_SOURCE)
#define PTE_LEVEL 0
/* Early POSIX */
#endif

#if defined(_POSIX_C_SOURCE) && _POSIX_C_SOURCE >= 199309
#undef PTE_LEVEL
#define PTE_LEVEL 1
/* Include 1b, 1c and 1d */
#endif

#if defined(INCLUDE_NP)
#undef PTE_LEVEL
#define PTE_LEVEL 2
/* Include Non-Portable extensions */
#endif

#define PTE_LEVEL_MAX 3

#if !defined(PTE_LEVEL)
#define PTE_LEVEL PTE_LEVEL_MAX
/* Include everything */
#endif

/*
 *
 */

/* Thread scheduling policies */

enum
{
 SCHED_OTHER = 0,
 SCHED_FIFO,
 SCHED_RR,
 SCHED_MIN = SCHED_OTHER,
 SCHED_MAX = SCHED_RR
};

struct sched_param
 {
 int sched_priority;
 };

#ifdef __cplusplus
extern "C"
 {
#endif /* __cplusplus */

 int sched_yield (void);

 int sched_get_priority_min (int policy);

 int sched_get_priority_max (int policy);

 int sched_setscheduler (pid_t pid, int policy);

 /*
 * Note that this macro returns ENOTSUP rather than
 * ENOSYS as might be expected. However, returning ENOSYS
 * should mean that sched_get_priority_{min,max} are
 * not implemented as well as sched_rr_get_interval.
 * This is not the case, since we just don't support
 * round-robin scheduling. Therefore I have chosen to
 * return the same value as sched_setscheduler when
 * SCHED_RR is passed to it.
 */
#define sched_rr_get_interval(_pid, _interval) \
 ( errno = ENOTSUP, (int) -1 )


#ifdef __cplusplus
 } /* End of extern "C" */
#endif /* __cplusplus */

#undef PTE_LEVEL
#undef PTE_LEVEL_MAX

#endif /* !_SCHED_H */