libc
/* $Id$ */
/* Copyright (c) 2012-2017 Pierre Pronchery <khorben@defora.org> */
/* This file is part of DeforaOS System libc */
/* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
* IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
* PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
* TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */
#include <sys/types.h>
#include <sys/ptrace.h>
#include <sys/wait.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
/* prototypes */
static int _ptrace(char const * progname);
static int _error(char const * progname, char const * message, int ret);
/* functions */
/* ptrace */
static int _ptrace_child(char const * progname);
static int _ptrace(char const * progname)
{
int ret = 0;
pid_t pid;
pid_t p;
int status;
if((pid = fork()) < 0)
return -_error(progname, "fork", 1);
if(pid == 0)
return _ptrace_child(progname);
for(;;)
if((p = waitpid(pid, &status, 0)) == pid)
{
if(WIFEXITED(status))
{
ret = WEXITSTATUS(status);
break;
}
else if(WIFSIGNALED(status))
{
ret = 1;
break;
}
else if(WIFSTOPPED(status)
&& ptrace(PT_CONTINUE, pid, (void *)1,
0) == 0)
break;
}
else if(p == -1)
{
ret = -_error(progname, "waitpid", 1);
if(errno == ECHILD)
break;
}
return ret;
}
static int _ptrace_child(char const * progname)
{
int ret = 0;
errno = 0;
if(ptrace(PT_TRACE_ME, 0, NULL, 0) != 0 && errno != 0)
ret = _error(progname, "PT_TRACE_ME", 1) + 1;
_exit(ret);
return -_error(progname, "exit", 1);
}
/* error */
static int _error(char const * progname, char const * message, int ret)
{
fprintf(stderr, "%s: %s: %s\n", progname, message, strerror(errno));
return ret;
}
/* main */
int main(int argc, char * argv[])
{
int ret = 0;
(void) argc;
ret |= _ptrace(argv[0]);
return (ret == 0) ? 0 : 2;
}