Gtest-exc.c revision 5fedf3407c7c161d12ba4f600cbce12fef780ad7 
1/* libunwind - a platform-independent unwind library
2   Copyright (C) 2001-2004 Hewlett-Packard Co
3	Contributed by David Mosberger-Tang <davidm@hpl.hp.com>
4
5Permission is hereby granted, free of charge, to any person obtaining
6a copy of this software and associated documentation files (the
7"Software"), to deal in the Software without restriction, including
8without limitation the rights to use, copy, modify, merge, publish,
9distribute, sublicense, and/or sell copies of the Software, and to
10permit persons to whom the Software is furnished to do so, subject to
11the following conditions:
12
13The above copyright notice and this permission notice shall be
14included in all copies or substantial portions of the Software.
15
16THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
17EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
18MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
19NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
20LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
21OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
22WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.  */
23
24/* This illustrates the basics of using the unwind interface for
25   exception handling.  */
26
27#ifdef HAVE_CONFIG_H
28# include "config.h"
29#endif
30
31#include <stdio.h>
32#include <stdlib.h>
33#include <unistd.h>
34
35#include <libunwind.h>
36
37#ifdef HAVE_IA64INTRIN_H
38# include <ia64intrin.h>
39#endif
40
41#define panic(args...)				\
42	{ ++nerrors; fprintf (stderr, args); }
43
44int nerrors = 0;
45int verbose = 0;
46int depth = 13;
47volatile int got_here = 0;
48
49extern void b (int);
50
51void
52raise_exception (void)
53{
54  unw_cursor_t cursor;
55  unw_context_t uc;
56  int i;
57
58  unw_getcontext (&uc);
59  if (unw_init_local (&cursor, &uc) < 0)
60    {
61      panic ("unw_init_local() failed!\n");
62      return;
63    }
64
65  /* unwind to top-most frame a(), skipping over b() and raise_exception(): */
66  for (i = 0; i < depth + 2; ++i)
67    if (unw_step (&cursor) < 0)
68      {
69	panic ("unw_step() failed!\n");
70	return;
71      }
72  unw_resume (&cursor);	/* transfer control to exception handler */
73}
74
75uintptr_t
76get_bsp (void)
77{
78#if UNW_TARGET_IA64
79# ifdef __INTEL_COMPILER
80  return __getReg (_IA64_REG_AR_BSP);
81# else
82  return (uintptr_t) __builtin_ia64_bsp ();
83# endif
84#else
85  return 0;
86#endif
87}
88
89int
90a (int n)
91{
92  long stack;
93  int result = 99;
94
95  if (verbose)
96    printf ("a(n=%d): sp=%p bsp=0x%lx\n",
97	    n, &stack, (unsigned long) get_bsp ());
98
99  if (n > 0)
100    a (n - 1);
101  else
102    b (16);
103
104  if (verbose)
105    {
106      printf ("exception handler: here we go (sp=%p, bsp=0x%lx)...\n",
107	      &stack, (unsigned long) get_bsp ());
108      /* This call works around a bug in gcc (up-to pre3.4) which
109	 causes invalid assembly code to be generated when
110	 __builtin_ia64_bsp() gets predicated.  */
111      getpid ();
112    }
113  if (n == depth)
114    {
115      result = 0;
116      got_here = 1;
117    }
118  return result;
119}
120
121void
122b (int n)
123{
124  if ((n & 1) == 0)
125    {
126      if (verbose)
127	printf ("b(n=%d) calling raise_exception()\n", n);
128      raise_exception ();
129    }
130  panic ("FAILURE: b() returned from raise_exception()!!\n");
131}
132
133int
134main (int argc, char **argv)
135{
136  int result;
137
138  if (argc > 1)
139    {
140      ++verbose;
141      depth = atol (argv[1]);
142      if (depth < 1)
143	{
144	  fprintf (stderr, "Usage: %s depth\n"
145		   "  depth must be >= 1\n", argv[0]);
146	  exit (-1);
147	}
148    }
149
150  result = a (depth);
151  if (result != 0 || !got_here || nerrors > 0)
152    {
153      fprintf (stderr,
154	       "FAILURE: test failed: result=%d got_here=%d nerrors=%d\n",
155	       result, got_here, nerrors);
156      exit (-1);
157    }
158
159  if (verbose)
160    printf ("SUCCESS!\n");
161  return 0;
162}
163