[deliverable/binutils-gdb.git] / gnulib / import / glthread / threadlib.c

/* Multithreading primitives.
   Copyright (C) 2005-2021 Free Software Foundation, Inc.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3, or (at your option)
   any later version.

   This program 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 General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, see <https://www.gnu.org/licenses/>.  */

/* Written by Bruno Haible <bruno@clisp.org>, 2005.  */

#include <config.h>

/* ========================================================================= */

#if USE_POSIX_THREADS || USE_ISOC_AND_POSIX_THREADS

/* Use the POSIX threads library.  */

# include <errno.h>
# include <pthread.h>
# include <stdlib.h>

# if PTHREAD_IN_USE_DETECTION_HARD

#  if defined __FreeBSD__ || defined __DragonFly__                 /* FreeBSD */

/* Test using pthread_key_create.  */

int
glthread_in_use (void)
{
  static int tested;
  static int result; /* 1: linked with -lpthread, 0: only with libc */

  if (!tested)
    {
      pthread_key_t key;
      int err = pthread_key_create (&key, NULL);

      if (err == ENOSYS)
        result = 0;
      else
        {
          result = 1;
          if (err == 0)
            pthread_key_delete (key);
        }
      tested = 1;
    }
  return result;
}

#  else                                                     /* Solaris, HP-UX */

/* Test using pthread_create.  */

/* The function to be executed by a dummy thread.  */
static void *
dummy_thread_func (void *arg)
{
  return arg;
}

int
glthread_in_use (void)
{
  static int tested;
  static int result; /* 1: linked with -lpthread, 0: only with libc */

  if (!tested)
    {
      pthread_t thread;

      if (pthread_create (&thread, NULL, dummy_thread_func, NULL) != 0)
        /* Thread creation failed.  */
        result = 0;
      else
        {
          /* Thread creation works.  */
          void *retval;
          if (pthread_join (thread, &retval) != 0)
            abort ();
          result = 1;
        }
      tested = 1;
    }
  return result;
}

#  endif

# endif

#endif

/* ========================================================================= */

/* This declaration is solely to ensure that after preprocessing
   this file is never empty.  */
typedef int dummy;
Commit	Line	Data
5abebf3c	1	/* Multithreading primitives.
9c9d63b1	2	Copyright (C) 2005-2021 Free Software Foundation, Inc.
5abebf3c CB	3
	4	This program is free software; you can redistribute it and/or modify
	5	it under the terms of the GNU General Public License as published by
	6	the Free Software Foundation; either version 3, or (at your option)
	7	any later version.
	8
	9	This program is distributed in the hope that it will be useful,
	10	but WITHOUT ANY WARRANTY; without even the implied warranty of
	11	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	12	GNU General Public License for more details.
	13
	14	You should have received a copy of the GNU General Public License
c0c3707f	15	along with this program; if not, see <https://www.gnu.org/licenses/>. */
5abebf3c CB	16
	17	/* Written by Bruno Haible <bruno@clisp.org>, 2005. */
	18
	19	#include <config.h>
	20
	21	/* ========================================================================= */
	22
c0c3707f	23	#if USE_POSIX_THREADS \|\| USE_ISOC_AND_POSIX_THREADS
5abebf3c CB	24
	25	/* Use the POSIX threads library. */
	26
9c9d63b1	27	# include <errno.h>
5abebf3c CB	28	# include <pthread.h>
	29	# include <stdlib.h>
	30
	31	# if PTHREAD_IN_USE_DETECTION_HARD
	32
9c9d63b1 PM	33	# if defined __FreeBSD__ \|\| defined __DragonFly__ /* FreeBSD */
	34
	35	/* Test using pthread_key_create. */
	36
	37	int
	38	glthread_in_use (void)
	39	{
	40	static int tested;
	41	static int result; /* 1: linked with -lpthread, 0: only with libc */
	42
	43	if (!tested)
	44	{
	45	pthread_key_t key;
	46	int err = pthread_key_create (&key, NULL);
	47
	48	if (err == ENOSYS)
	49	result = 0;
	50	else
	51	{
	52	result = 1;
	53	if (err == 0)
	54	pthread_key_delete (key);
	55	}
	56	tested = 1;
	57	}
	58	return result;
	59	}
	60
	61	# else /* Solaris, HP-UX */
	62
	63	/* Test using pthread_create. */
	64
5abebf3c CB	65	/* The function to be executed by a dummy thread. */
	66	static void *
	67	dummy_thread_func (void *arg)
	68	{
	69	return arg;
	70	}
	71
	72	int
	73	glthread_in_use (void)
	74	{
	75	static int tested;
	76	static int result; /* 1: linked with -lpthread, 0: only with libc */
	77
	78	if (!tested)
	79	{
	80	pthread_t thread;
	81
	82	if (pthread_create (&thread, NULL, dummy_thread_func, NULL) != 0)
	83	/* Thread creation failed. */
	84	result = 0;
	85	else
	86	{
	87	/* Thread creation works. */
	88	void *retval;
	89	if (pthread_join (thread, &retval) != 0)
	90	abort ();
	91	result = 1;
	92	}
	93	tested = 1;
	94	}
	95	return result;
	96	}
	97
9c9d63b1 PM	98	# endif
9c9d63b1 PM	99
5abebf3c CB	100	# endif
	101
	102	#endif
	103
	104	/* ========================================================================= */
	105
	106	/* This declaration is solely to ensure that after preprocessing
	107	this file is never empty. */
	108	typedef int dummy;