summary refs log tree commit diff
path: root/debug/tst-backtrace5.c
blob: b2f46160e7a9fcfc7c1f97f786509ae2d92dee7b (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
/* Test backtrace and backtrace_symbols for signal frames, where a
   system call was interrupted by a signal.
   Copyright (C) 2011-2020 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 <execinfo.h>
#include <search.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <signal.h>
#include <unistd.h>

#include "tst-backtrace.h"

#ifndef SIGACTION_FLAGS
# define SIGACTION_FLAGS 0
#endif

/* The backtrace should include at least handle_signal, a signal
   trampoline, read, 3 * fn, and do_test.  */
#define NUM_FUNCTIONS 7

void
handle_signal (int signum)
{
  void *addresses[NUM_FUNCTIONS];
  char **symbols;
  int n;
  int i;

  /* Get the backtrace addresses.  */
  n = backtrace (addresses, sizeof (addresses) / sizeof (addresses[0]));
  printf ("Obtained backtrace with %d functions\n", n);
  /*  Check that there are at least seven functions.  */
  if (n < NUM_FUNCTIONS)
    {
      FAIL ();
      return;
    }
  /* Convert them to symbols.  */
  symbols = backtrace_symbols (addresses, n);
  /* Check that symbols were obtained.  */
  if (symbols == NULL)
    {
      FAIL ();
      return;
    }
  for (i = 0; i < n; ++i)
    printf ("Function %d: %s\n", i, symbols[i]);
  /* Check that the function names obtained are accurate.  */
  if (!match (symbols[0], "handle_signal"))
    {
      FAIL ();
      return;
    }

  /* Do not check name for signal trampoline or cancellable syscall
     wrappers (__syscall_cancel*).  */
  for (; i < n - 1; i++)
    if (match (symbols[i], "read"))
      break;
  if (i == n - 1)
    {
      FAIL ();
      return;
    }

  for (; i < n - 1; i++)
    if (!match (symbols[i], "fn"))
      {
	FAIL ();
	return;
      }
  /* Symbol names are not available for static functions, so we do not
     check do_test.  */

  /* Check that backtrace does not return more than what fits in the array
     (bug 25423).  */
  for (int j = 0; j < NUM_FUNCTIONS; j++)
    {
      n = backtrace (addresses, j);
      if (n > j)
	{
	  FAIL ();
	  return;
	}
    }
}

NO_INLINE int
fn (int c, int flags)
{
  pid_t parent_pid, child_pid;
  int pipefd[2];
  char r[1];
  struct sigaction act;

  if (c > 0)
    {
      fn (c - 1, flags);
      return x;
    }

  memset (&act, 0, sizeof (act));
  act.sa_handler = handle_signal;
  act.sa_flags = flags;
  sigemptyset (&act.sa_mask);
  sigaction (SIGUSR1, &act, NULL);
  parent_pid = getpid ();
  if (pipe (pipefd) == -1)
    abort ();

  child_pid = fork ();
  if (child_pid == (pid_t) -1)
    abort ();
  else if (child_pid == 0)
    {
      sleep (1);
      kill (parent_pid, SIGUSR1);
      _exit (0);
    }

  /* In the parent.  */
  read (pipefd[0], r, 1);

  return 0;
}

NO_INLINE int
do_test (void)
{
  fn (2, SIGACTION_FLAGS);
  return ret;
}

#include <support/test-driver.c>