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/* { dg-do run } */
/* { dg-require-effective-target split_stack } */
/* { dg-require-effective-target pthread_h } */
/* { dg-require-effective-target ucontext_h } */
/* { dg-options "-pthread -fsplit-stack" } */
#include <stdlib.h>
#include <pthread.h>
#include <ucontext.h>
extern void __splitstack_getcontext (void *context[10]);
extern void __splitstack_setcontext (void *context[10]);
extern void *__splitstack_makecontext (size_t, void *context[10], size_t *);
extern void __splitstack_block_signals (int *, int *);
extern void __splitstack_block_signals_context (void *context[10], int *,
int *);
extern void *__splitstack_find (void *, void *, size_t *, void **, void **,
void **);
extern void *__splitstack_find_context (void *context[10], size_t *, void **,
void **, void **);
static ucontext_t c1;
static void *s1[10];
static ucontext_t c2;
static void *s2[10];
static void swap (ucontext_t *, void *fs[10], ucontext_t *, void *ts[10])
__attribute__ ((no_split_stack));
static void
swap (ucontext_t *fu, void *fs[10], ucontext_t *tu, void *ts[10])
{
__splitstack_getcontext (fs);
__splitstack_setcontext (ts);
swapcontext (fu, tu);
__splitstack_setcontext (fs);
}
/* Use a noinline function to ensure that the buffer is not removed
from the stack. */
static void use_buffer (char *buf) __attribute__ ((noinline));
static void
use_buffer (char *buf)
{
buf[0] = '\0';
}
static void
down (int i, const char *msg, ucontext_t *me, void *mes[10],
ucontext_t *other, void *others[10])
{
char buf[10000];
if (i > 0)
{
use_buffer (buf);
swap (me, mes, other, others);
down (i - 1, msg, me, mes, other, others);
}
else
{
int c = 0;
void *stack;
size_t stack_size;
void *next_segment = NULL;
void *next_sp = NULL;
void *initial_sp = NULL;
stack = __splitstack_find_context (mes, &stack_size, &next_segment,
&next_sp, &initial_sp);
if (stack != NULL)
{
++c;
while (__splitstack_find (next_segment, next_sp, &stack_size,
&next_segment, &next_sp, &initial_sp)
!= NULL)
++c;
}
}
}
static void
go1 (void)
{
down (1000, "go1", &c1, s1, &c2, s2);
pthread_exit (NULL);
}
static void
go2 (void)
{
down (1000, "go2", &c2, s2, &c1, s1);
pthread_exit (NULL);
}
struct thread_context
{
ucontext_t *u;
void **s;
};
static void *start_thread (void *) __attribute__ ((no_split_stack));
static void *
start_thread (void *context)
{
struct thread_context *tc = (struct thread_context *) context;
int block;
block = 0;
__splitstack_block_signals (&block, NULL);
__splitstack_setcontext (tc->s);
setcontext (tc->u);
abort ();
}
int
main (int argc __attribute__ ((unused)), char **argv __attribute__ ((unused)))
{
pthread_t tid;
int err;
size_t size;
struct thread_context tc;
int block;
if (getcontext (&c1) < 0)
abort ();
c2 = c1;
c1.uc_stack.ss_sp = __splitstack_makecontext (8192, &s1[0], &size);
if (c1.uc_stack.ss_sp == NULL)
abort ();
c1.uc_stack.ss_flags = 0;
c1.uc_stack.ss_size = size;
c1.uc_link = NULL;
block = 0;
__splitstack_block_signals_context (&s1[0], &block, NULL);
makecontext (&c1, go1, 0);
c2.uc_stack.ss_sp = __splitstack_makecontext (8192, &s2[0], &size);
if (c2.uc_stack.ss_sp == NULL)
abort ();
c2.uc_stack.ss_flags = 0;
c2.uc_stack.ss_size = size;
c2.uc_link = NULL;
__splitstack_block_signals_context (&s2[0], &block, NULL);
makecontext (&c2, go2, 0);
block = 0;
__splitstack_block_signals (&block, NULL);
tc.u = &c1;
tc.s = &s1[0];
err = pthread_create (&tid, NULL, start_thread, &tc);
if (err != 0)
abort ();
err = pthread_join (tid, NULL);
if (err != 0)
abort ();
return 0;
}
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