[thirdparty/glibc.git] / nptl / pthread_mutex_init.c

/* Copyright (C) 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.

   The GNU C 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 2.1 of the License, or (at your option) any later version.

   The GNU C 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 the GNU C Library; if not, write to the Free
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307 USA.  */

#include <assert.h>
#include <errno.h>
#include <string.h>
#include "pthreadP.h"


static const struct pthread_mutexattr default_attr =
  {
    /* Default is a normal mutex, not shared between processes.  */
    .mutexkind = PTHREAD_MUTEX_NORMAL
  };


int
__pthread_mutex_init (mutex, mutexattr)
     pthread_mutex_t *mutex;
     const pthread_mutexattr_t *mutexattr;
{
  const struct pthread_mutexattr *imutexattr;

  assert (sizeof (pthread_mutex_t) <= __SIZEOF_PTHREAD_MUTEX_T);

  imutexattr = (const struct pthread_mutexattr *) mutexattr ?: &default_attr;

  /* Sanity checks.  */
  // XXX For now we cannot implement robust mutexes if they are shared.
  if ((imutexattr->mutexkind & PTHREAD_MUTEXATTR_FLAG_ROBUST) != 0
      && (imutexattr->mutexkind & PTHREAD_MUTEXATTR_FLAG_PSHARED) != 0)
    return ENOTSUP;

  /* Clear the whole variable.  */
  memset (mutex, '\0', __SIZEOF_PTHREAD_MUTEX_T);

  /* Copy the values from the attribute.  */
  mutex->__data.__kind = imutexattr->mutexkind & ~PTHREAD_MUTEXATTR_FLAG_BITS;
  if ((imutexattr->mutexkind & PTHREAD_MUTEXATTR_FLAG_ROBUST) != 0)
    mutex->__data.__kind |= PTHREAD_MUTEX_ROBUST_PRIVATE_NP;

  /* Default values: mutex not used yet.  */
  // mutex->__count = 0;	already done by memset
  // mutex->__owner = 0;	already done by memset
  // mutex->__nusers = 0;	already done by memset
  // mutex->__spins = 0;	already done by memset
  // mutex->__next = NULL;	already done by memset

  return 0;
}
strong_alias (__pthread_mutex_init, pthread_mutex_init)
INTDEF(__pthread_mutex_init)
Commit	Line	Data
1bcfb5a5	1	/* Copyright (C) 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
76a50749 UD	2	This file is part of the GNU C Library.
	3	Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
	4
	5	The GNU C Library is free software; you can redistribute it and/or
	6	modify it under the terms of the GNU Lesser General Public
	7	License as published by the Free Software Foundation; either
	8	version 2.1 of the License, or (at your option) any later version.
	9
	10	The GNU C Library is distributed in the hope that it will be useful,
	11	but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	13	Lesser General Public License for more details.
	14
	15	You should have received a copy of the GNU Lesser General Public
	16	License along with the GNU C Library; if not, write to the Free
	17	Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
	18	02111-1307 USA. */
	19
	20	#include <assert.h>
1bcfb5a5	21	#include <errno.h>
76a50749 UD	22	#include <string.h>
	23	#include "pthreadP.h"
	24
a334319f	25
76a50749 UD	26	static const struct pthread_mutexattr default_attr =
	27	{
	28	/* Default is a normal mutex, not shared between processes. */
	29	.mutexkind = PTHREAD_MUTEX_NORMAL
	30	};
	31
	32
	33	int
	34	__pthread_mutex_init (mutex, mutexattr)
	35	pthread_mutex_t *mutex;
	36	const pthread_mutexattr_t *mutexattr;
	37	{
	38	const struct pthread_mutexattr *imutexattr;
	39
	40	assert (sizeof (pthread_mutex_t) <= __SIZEOF_PTHREAD_MUTEX_T);
	41
	42	imutexattr = (const struct pthread_mutexattr *) mutexattr ?: &default_attr;
	43
1bcfb5a5 UD	44	/* Sanity checks. */
	45	// XXX For now we cannot implement robust mutexes if they are shared.
	46	if ((imutexattr->mutexkind & PTHREAD_MUTEXATTR_FLAG_ROBUST) != 0
	47	&& (imutexattr->mutexkind & PTHREAD_MUTEXATTR_FLAG_PSHARED) != 0)
	48	return ENOTSUP;
	49
76a50749 UD	50	/* Clear the whole variable. */
	51	memset (mutex, '\0', __SIZEOF_PTHREAD_MUTEX_T);
	52
	53	/* Copy the values from the attribute. */
1bcfb5a5 UD	54	mutex->__data.__kind = imutexattr->mutexkind & ~PTHREAD_MUTEXATTR_FLAG_BITS;
	55	if ((imutexattr->mutexkind & PTHREAD_MUTEXATTR_FLAG_ROBUST) != 0)
	56	mutex->__data.__kind \|= PTHREAD_MUTEX_ROBUST_PRIVATE_NP;
76a50749 UD	57
	58	/* Default values: mutex not used yet. */
	59	// mutex->__count = 0; already done by memset
61623643 UD	60	// mutex->__owner = 0; already done by memset
61623643 UD	61	// mutex->__nusers = 0; already done by memset
2c0b891a	62	// mutex->__spins = 0; already done by memset
1bcfb5a5	63	// mutex->__next = NULL; already done by memset
76a50749 UD	64
	65	return 0;
	66	}
	67	strong_alias (__pthread_mutex_init, pthread_mutex_init)
83614008	68	INTDEF(__pthread_mutex_init)