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/* libunwind - a platform-independent unwind library
Copyright (C) 2003-2004 Hewlett-Packard Co
Contributed by David Mosberger-Tang <davidm@hpl.hp.com>
This file is part of libunwind.
Copyright (c) 2003 Hewlett-Packard Co.
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. */
#include "compiler.h"
#include <libunwind.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/resource.h>
#include <sys/mman.h>
#define panic(args...) \
{ fprintf (stderr, args); exit (-1); }
void * stack_start;
#define PAGE_SIZE 4096
void do_backtrace (void)
{
void* buffer[1024];
int size = 1024;
mprotect((void*)((uintptr_t)stack_start & ~(PAGE_SIZE - 1)),
PAGE_SIZE, PROT_NONE);
unw_cursor_t cursor;
unw_word_t ip, sp;
unw_context_t uc;
int ret;
int steps = 0;
unw_getcontext (&uc);
if (unw_init_local (&cursor, &uc) < 0)
panic ("unw_init_local failed!\n");
do
{
unw_get_reg (&cursor, UNW_REG_IP, &ip);
unw_get_reg (&cursor, UNW_REG_SP, &sp);
ret = unw_step (&cursor);
if (ret < 0)
{
unw_get_reg (&cursor, UNW_REG_IP, &ip);
}
steps ++;
}
while (ret > 0);
if (steps < 5)
{
exit(-1);
}
mprotect((void*)((uintptr_t)stack_start & ~(PAGE_SIZE - 1)),
PAGE_SIZE, PROT_READ|PROT_WRITE);
}
void consume_and_run (int depth)
{
unw_cursor_t cursor;
unw_context_t uc;
char string[1024];
sprintf (string, "hello %p %p\n", &cursor, &uc);
if (depth == 0) {
do_backtrace();
} else {
consume_and_run(depth - 1);
}
}
int
main (int argc, char **argv UNUSED)
{
int start;
unw_context_t uc;
unw_cursor_t cursor;
stack_start = &start;
// Initialize pipe mem validate check, opens file descriptors
unw_getcontext(&uc);
if (unw_init_local (&cursor, &uc) < 0)
panic ("unw_init_local failed!\n");
int i;
for (i = 3; i < 10; i++)
{
pid_t childpid = fork();
if (!childpid)
{
/* Close fds and make sure we still work */
int ret = close(i);
}
int status;
if (childpid)
{
wait(&status);
if (WIFEXITED(status))
return WEXITSTATUS(status);
else
return -1;
}
else
{
consume_and_run (10);
return 0;
}
}
return 0;
}
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