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/* Copyright (c) 2012-2013, The Tor Project, Inc. */
/* See LICENSE for licensing information */
#include "orconfig.h"
#include <stdio.h>
#include <stdlib.h>
#include "or.h"
#include "util.h"
#include "backtrace.h"
#include "torlog.h"
/* -1: no crash.
* 0: crash with a segmentation fault.
* 1x: crash with an assertion failure. */
static int crashtype = 0;
#ifdef __GNUC__
#define NOINLINE __attribute__((noinline))
#define NORETURN __attribute__((noreturn))
#endif
int crash(int x) NOINLINE;
int oh_what(int x) NOINLINE;
int a_tangled_web(int x) NOINLINE;
int we_weave(int x) NOINLINE;
static void abort_handler(int s) NORETURN;
int
crash(int x)
{
if (crashtype == 0) {
*(volatile int *)0 = 0;
} else if (crashtype == 1) {
tor_assert(1 == 0);
} else if (crashtype == -1) {
;
}
crashtype *= x;
return crashtype;
}
int
oh_what(int x)
{
/* We call crash() twice here, so that the compiler won't try to do a
* tail-call optimization. Only the first call will actually happen, but
* telling the compiler to maybe do the second call will prevent it from
* replacing the first call with a jump. */
return crash(x) + crash(x*2);
}
int
a_tangled_web(int x)
{
return oh_what(x) * 99 + oh_what(x);
}
int
we_weave(int x)
{
return a_tangled_web(x) + a_tangled_web(x+1);
}
static void
abort_handler(int s)
{
(void)s;
exit(0);
}
int
main(int argc, char **argv)
{
log_severity_list_t severity;
if (argc < 2) {
puts("I take an argument. It should be \"assert\" or \"crash\" or "
"\"none\"");
return 1;
}
if (!strcmp(argv[1], "assert")) {
crashtype = 1;
} else if (!strcmp(argv[1], "crash")) {
crashtype = 0;
} else if (!strcmp(argv[1], "none")) {
crashtype = -1;
} else {
puts("Argument should be \"assert\" or \"crash\" or \"none\"");
return 1;
}
init_logging();
set_log_severity_config(LOG_WARN, LOG_ERR, &severity);
add_stream_log(&severity, "stdout", STDOUT_FILENO);
tor_log_update_sigsafe_err_fds();
configure_backtrace_handler(NULL);
signal(SIGABRT, abort_handler);
printf("%d\n", we_weave(2));
clean_up_backtrace_handler();
return 0;
}
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