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/* Test backtrace and backtrace_symbols for signal frames, where a
system call was interrupted by a signal.
Copyright (C) 2011-2013 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
<http://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>
static int do_test (void);
#define TEST_FUNCTION do_test ()
#include "../test-skeleton.c"
/* Set to a non-zero value if the test fails. */
volatile int ret;
/* Accesses to X are used to prevent optimization. */
volatile int x;
/* Called if the test fails. */
#define FAIL() \
do { printf ("Failure on line %d\n", __LINE__); ret = 1; } while (0)
/* The backtrace should include at least handle_signal, a signal
trampoline, read, 3 * fn, and do_test. */
#define NUM_FUNCTIONS 7
/* Use this attribute to prevent inlining, so that all expected frames
are present. */
#define NO_INLINE __attribute__ ((noinline))
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 (strstr (symbols[0], "handle_signal") == NULL)
{
FAIL ();
return;
}
/* Do not check name for signal trampoline. */
i = 2;
if (strstr (symbols[i++], "read") == NULL)
{
/* Perhaps symbols[2] is __kernel_vsyscall? */
if (strstr (symbols[i++], "read") == NULL)
{
FAIL ();
return;
}
}
for (; i < n - 1; i++)
if (strstr (symbols[i], "fn") == NULL)
{
FAIL ();
return;
}
/* Symbol names are not available for static functions, so we do not
check do_test. */
}
NO_INLINE int
fn (int c)
{
pid_t parent_pid, child_pid;
int pipefd[2];
char r[1];
struct sigaction act;
if (c > 0)
{
fn (c - 1);
return x;
}
memset (&act, 0, sizeof (act));
act.sa_handler = handle_signal;
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 static int
do_test (void)
{
fn (2);
return ret;
}
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