Home | History | Annotate | Download | only in tests 
      1 /* libunwind - a platform-independent unwind library
      2    Copyright (C) 2004 Hewlett-Packard Co
      3 	Contributed by David Mosberger-Tang <davidm (at) hpl.hp.com>
      4 
      5 Permission is hereby granted, free of charge, to any person obtaining
      6 a copy of this software and associated documentation files (the
      7 "Software"), to deal in the Software without restriction, including
      8 without limitation the rights to use, copy, modify, merge, publish,
      9 distribute, sublicense, and/or sell copies of the Software, and to
     10 permit persons to whom the Software is furnished to do so, subject to
     11 the following conditions:
     12 
     13 The above copyright notice and this permission notice shall be
     14 included in all copies or substantial portions of the Software.
     15 
     16 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
     17 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
     18 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
     19 NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
     20 LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
     21 OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
     22 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.  */
     23 
     24 /* Test to verify that we can siglongjmp() into a frame whose register
     25    window is not backed by valid memory.  */
     26 
     27 #ifdef HAVE_CONFIG_H
     28 # include "config.h"
     29 #endif
     30 
     31 #include <errno.h>
     32 #include <stdio.h>
     33 #include <stdint.h>
     34 #include <setjmp.h>
     35 #include <signal.h>
     36 #include <stdlib.h>
     37 #include <string.h>
     38 #include <unistd.h>
     39 
     40 #include <sys/mman.h>
     41 
     42 #ifdef HAVE_IA64INTRIN_H
     43 # include <ia64intrin.h>
     44 #endif
     45 
     46 static sigjmp_buf env;
     47 static int return_level;
     48 static uintptr_t return_bsp;
     49 static int verbose;
     50 
     51 uintptr_t
     52 get_bsp (void)
     53 {
     54 #ifdef __INTEL_COMPILER
     55   return __getReg (_IA64_REG_AR_BSP);
     56 #else
     57   return (uintptr_t) __builtin_ia64_bsp ();
     58 #endif
     59 }
     60 
     61 static void
     62 sighandler (int signal, void *siginfo, void *sigcontext)
     63 {
     64   ucontext_t *uc = sigcontext;
     65   int local = 0;
     66 
     67   if (verbose)
     68     printf ("got signal, stack at %p, saved bsp=0x%lx\n",
     69 	    &local, uc->uc_mcontext.sc_ar_bsp);
     70   siglongjmp (env, 1);
     71 }
     72 
     73 /* Direct call of doit () at the end of doit () would get optimized by GCC to
     74    a branch.  */
     75 static void doit (int n);
     76 typedef void (*doit_type) (int);
     77 static volatile doit_type doit_pointer = doit;
     78 
     79 static void
     80 doit (int n)
     81 {
     82   uintptr_t guard_page_addr, bsp = get_bsp ();
     83   void *ret;
     84 
     85   if (n == 0)
     86     {
     87       size_t page_size = getpagesize ();
     88 
     89       guard_page_addr = (bsp + page_size - 1) & -page_size;
     90       if (verbose)
     91 	printf ("guard_page_addr = 0x%lx\n", (unsigned long) guard_page_addr);
     92       ret = mmap ((void *) guard_page_addr, page_size, PROT_NONE,
     93 		  MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
     94       if (ret != (void *) guard_page_addr)
     95 	{
     96 	  if (ret == MAP_FAILED)
     97 	    perror ("mmap");
     98 	  else
     99 	    fprintf (stderr, "mmap() returned %p, expected 0x%lx\n",
    100 		     ret, guard_page_addr);
    101 	  exit (EXIT_FAILURE);
    102 	}
    103     }
    104 
    105   if (sigsetjmp (env, 1))
    106     {
    107       return_level = n;
    108       return_bsp = bsp;
    109     }
    110   else
    111     (*doit_pointer) (n + 1);
    112 }
    113 
    114 int
    115 main (int argc, char **argv)
    116 {
    117   struct sigaction sa;
    118   stack_t ss;
    119 
    120   if (argc > 1)
    121     verbose = 1;
    122 
    123   ss.ss_sp = malloc (2 * SIGSTKSZ);
    124   if (ss.ss_sp == NULL)
    125     {
    126       puts ("failed to allocate alternate stack");
    127       return EXIT_FAILURE;
    128     }
    129   ss.ss_flags = 0;
    130   ss.ss_size = 2 * SIGSTKSZ;
    131   if (sigaltstack (&ss, NULL) < 0)
    132     {
    133       printf ("sigaltstack failed: %s\n", strerror (errno));
    134       return EXIT_FAILURE;
    135     }
    136 
    137   sa.sa_handler = (void (*) (int)) sighandler;
    138   sigemptyset (&sa.sa_mask);
    139   sa.sa_flags = SA_SIGINFO | SA_ONSTACK;
    140   if (sigaction (SIGSEGV, &sa, NULL) < 0)
    141     {
    142       printf ("sigaction failed: %s\n", strerror (errno));
    143       exit (1);
    144     }
    145 
    146   doit (0);
    147 
    148   if (verbose)
    149     {
    150       printf ("sigsetjmp returned at level %d bsp=0x%lx\n",
    151 	      return_level, return_bsp);
    152       puts ("Test succeeded!");
    153     }
    154   return EXIT_SUCCESS;
    155 }
    156