tests/ia64-test-setjmp.c

/* libunwind - a platform-independent unwind library
   Copyright (C) 2004 Hewlett-Packard Co
	Contributed by David Mosberger-Tang <davidm@hpl.hp.com>

Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
"Software"), to deal in the Software without restriction, including
without limitation the rights to use, copy, modify, merge, publish,
distribute, sublicense, and/or sell copies of the Software, and to
permit persons to whom the Software is furnished to do so, subject to
the following conditions:

The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.  */

/* Test to verify that we can siglongjmp() into a frame whose register
   window is not backed by valid memory.  */

#ifdef HAVE_CONFIG_H
# include "config.h"
#endif

#include <errno.h>
#include <stdio.h>
#include <stdint.h>
#include <setjmp.h>
#include <signal.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include <sys/mman.h>

#ifdef HAVE_IA64INTRIN_H
# include <ia64intrin.h>
#endif

static sigjmp_buf env;
static int return_level;
static uintptr_t return_bsp;
static int verbose;

uintptr_t
get_bsp (void)
{
#ifdef __INTEL_COMPILER
  return __getReg (_IA64_REG_AR_BSP);
#else
  return (uintptr_t) __builtin_ia64_bsp ();
#endif
}

static void
sighandler (int signal, void *siginfo, void *sigcontext)
{
  ucontext_t *uc = sigcontext;
  int local = 0;

  if (verbose)
    printf ("got signal, stack at %p, saved bsp=0x%lx\n",
	    &local, uc->uc_mcontext.sc_ar_bsp);
  siglongjmp (env, 1);
}

/* Direct call of doit () at the end of doit () would get optimized by GCC to
   a branch.  */
static void doit (int n);
static volatile void (*doit_pointer) (int n) = doit;

static void
doit (int n)
{
  uintptr_t guard_page_addr, bsp = get_bsp ();
  void *ret;

  if (n == 0)
    {
      size_t page_size = getpagesize ();

      guard_page_addr = (bsp + page_size - 1) & -page_size;
      if (verbose)
	printf ("guard_page_addr = 0x%lx\n", (unsigned long) guard_page_addr);
      ret = mmap ((void *) guard_page_addr, page_size, PROT_NONE,
		  MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
      if (ret != (void *) guard_page_addr)
	{
	  if (ret == MAP_FAILED)
	    perror ("mmap");
	  else
	    fprintf (stderr, "mmap() returned %p, expected 0x%lx\n",
		     ret, guard_page_addr);
	  exit (EXIT_FAILURE);
	}
    }

  if (sigsetjmp (env, 1))
    {
      return_level = n;
      return_bsp = bsp;
    }
  else
    (*doit_pointer) (n + 1);
}

int
main (int argc, char **argv)
{
  struct sigaction sa;
  stack_t ss;

  if (argc > 1)
    verbose = 1;

  ss.ss_sp = malloc (2 * SIGSTKSZ);
  if (ss.ss_sp == NULL)
    {
      puts ("failed to allocate alternate stack");
      return EXIT_FAILURE;
    }
  ss.ss_flags = 0;
  ss.ss_size = 2 * SIGSTKSZ;
  if (sigaltstack (&ss, NULL) < 0)
    {
      printf ("sigaltstack failed: %s\n", strerror (errno));
      return EXIT_FAILURE;
    }

  sa.sa_handler = (void (*) (int)) sighandler;
  sigemptyset (&sa.sa_mask);
  sa.sa_flags = SA_SIGINFO | SA_ONSTACK;
  if (sigaction (SIGSEGV, &sa, NULL) < 0)
    {
      printf ("sigaction failed: %s\n", strerror (errno));
      exit (1);
    }

  doit (0);

  if (verbose)
    {
      printf ("sigsetjmp returned at level %d bsp=0x%lx\n",
	      return_level, return_bsp);
      puts ("Test succeeded!");
    }
  return EXIT_SUCCESS;
}