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/* Copyright (C) 2003 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@redhat.com>, 2003.
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 <errno.h>
#include <error.h>
#include <limits.h>
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <ucontext.h>
#define N 4
static char stacks[N][PTHREAD_STACK_MIN];
static ucontext_t ctx[N][2];
static volatile int failures;
static void
fct (long int n)
{
/* Just to use the thread local descriptor. */
printf ("%ld: in %s now\n", n, __FUNCTION__);
errno = 0;
}
static void *
tf (void *arg)
{
int n = (int) (long int) arg;
if (getcontext (&ctx[n][1]) != 0)
{
printf ("%d: cannot get context: %m\n", n);
exit (1);
}
printf ("%d: %s: before makecontext\n", n, __FUNCTION__);
ctx[n][1].uc_stack.ss_sp = stacks[n];
ctx[n][1].uc_stack.ss_size = PTHREAD_STACK_MIN;
ctx[n][1].uc_link = &ctx[n][0];
makecontext (&ctx[n][1], (void (*) (void)) fct, 1, (long int) n);
printf ("%d: %s: before swapcontext\n", n, __FUNCTION__);
if (swapcontext (&ctx[n][0], &ctx[n][1]) != 0)
{
++failures;
printf ("%d: %s: swapcontext failed\n", n, __FUNCTION__);
}
else
printf ("%d: back in %s\n", n, __FUNCTION__);
return NULL;
}
static volatile int global;
static int
do_test (void)
{
int n;
pthread_t th[N];
ucontext_t mctx;
puts ("making contexts");
if (getcontext (&mctx) != 0)
{
if (errno == ENOSYS)
{
puts ("context handling not supported");
exit (0);
}
printf ("%s: getcontext: %m\n", __FUNCTION__);
exit (1);
}
/* Play some tricks with this context. */
if (++global == 1)
if (setcontext (&mctx) != 0)
{
puts ("setcontext failed");
exit (1);
}
if (global != 2)
{
puts ("global not incremented twice");
exit (1);
}
puts ("global OK");
for (n = 0; n < N; ++n)
if (pthread_create (&th[n], NULL, tf, (void *) (long int) n) != 0)
{
puts ("create failed");
exit (1);
}
for (n = 0; n < N; ++n)
if (pthread_join (th[n], NULL) != 0)
{
puts ("join failed");
exit (1);
}
return failures;
}
#define TEST_FUNCTION do_test ()
#include "../test-skeleton.c"
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