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/* Copyright (C) 2003-2021 Free Software Foundation, Inc.
This file is part of the GNU C Library.
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, see
<https://www.gnu.org/licenses/>. */
#include <errno.h>
#include <error.h>
#include <limits.h>
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <ucontext.h>
#include <support/support.h>
#define N 4
#if __WORDSIZE == 64
#define GUARD_PATTERN 0xdeadbeafdeadbeaf
#else
#define GUARD_PATTERN 0xdeadbeaf
#endif
typedef struct {
ucontext_t uctx;
unsigned long guard[3];
} tst_context_t;
static char *stacks[N];
static size_t stack_size;
static tst_context_t ctx[N][2];
static volatile int failures;
static void
fct (long int n)
{
char on_stack[1];
/* Just to use the thread local descriptor. */
printf ("%ld: in %s now, on_stack = %p\n", n, __FUNCTION__, on_stack);
errno = 0;
if (ctx[n][1].uctx.uc_link != &ctx[n][0].uctx)
{
printf ("context[%ld][1] uc_link damaged, = %p\n", n,
ctx[n][1].uctx.uc_link);
exit (1);
}
if ((ctx[n][0].guard[0] != GUARD_PATTERN)
|| (ctx[n][0].guard[1] != GUARD_PATTERN)
|| (ctx[n][0].guard[2] != GUARD_PATTERN))
{
printf ("%ld: %s context[0] overflow detected!\n", n, __FUNCTION__);
++failures;
}
if ((ctx[n][1].guard[0] != GUARD_PATTERN)
|| (ctx[n][1].guard[1] != GUARD_PATTERN)
|| (ctx[n][1].guard[2] != GUARD_PATTERN))
{
printf ("%ld: %s context[1] overflow detected!\n", n, __FUNCTION__);
++failures;
}
if (n < 0 || n >= N)
{
printf ("%ld out of range\n", n);
exit (1);
}
if (on_stack < stacks[n] || on_stack >= stacks[n] + stack_size)
{
printf ("%ld: on_stack not on appropriate stack\n", n);
exit (1);
}
}
static void *
tf (void *arg)
{
int n = (int) (long int) arg;
ctx[n][0].guard[0] = GUARD_PATTERN;
ctx[n][0].guard[1] = GUARD_PATTERN;
ctx[n][0].guard[2] = GUARD_PATTERN;
ctx[n][1].guard[0] = GUARD_PATTERN;
ctx[n][1].guard[1] = GUARD_PATTERN;
ctx[n][1].guard[2] = GUARD_PATTERN;
if (getcontext (&ctx[n][1].uctx) != 0)
{
printf ("%d: cannot get context: %m\n", n);
exit (1);
}
printf ("%d: %s: before makecontext\n", n, __FUNCTION__);
ctx[n][1].uctx.uc_stack.ss_sp = stacks[n];
ctx[n][1].uctx.uc_stack.ss_size = stack_size;
ctx[n][1].uctx.uc_link = &ctx[n][0].uctx;
makecontext (&ctx[n][1].uctx, (void (*) (void)) fct, 1, (long int) n);
printf ("%d: %s: before swapcontext\n", n, __FUNCTION__);
if (swapcontext (&ctx[n][0].uctx, &ctx[n][1].uctx) != 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;
stack_size = 2 * PTHREAD_STACK_MIN;
for (int i = 0; i < N; i++)
stacks[i] = xmalloc (stack_size);
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");
pthread_attr_t at;
if (pthread_attr_init (&at) != 0)
{
puts ("attr_init failed");
return 1;
}
if (pthread_attr_setstacksize (&at, 1 * 1024 * 1024) != 0)
{
puts ("attr_setstacksize failed");
return 1;
}
for (n = 0; n < N; ++n)
if (pthread_create (&th[n], &at, tf, (void *) (long int) n) != 0)
{
puts ("create failed");
exit (1);
}
if (pthread_attr_destroy (&at) != 0)
{
puts ("attr_destroy failed");
return 1;
}
for (n = 0; n < N; ++n)
if (pthread_join (th[n], NULL) != 0)
{
puts ("join failed");
exit (1);
}
for (int i = 0; i < N; i++)
free (stacks[i]);
return failures;
}
#define TEST_FUNCTION do_test ()
#include "../test-skeleton.c"
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