Attachment 147568 Details for Bug 227693 – testcase

testcase

ptrace_step_sig.c (text/x-csrc), 5.28 KB, created by Mark Wielaard on 2007-02-07 16:49:23 UTC

(hide)

Description:

Filename:

MIME Type:

Creator: Mark Wielaard

Created: 2007-02-07 16:49:23 UTC

Size: 5.28 KB

patch

obsolete

>// This file is part of the program FRYSK.
>//
>// Copyright 2007, Red Hat Inc.
>//
>// FRYSK is free software; you can redistribute it and/or modify it
>// under the terms of the GNU General Public License as published by
>// the Free Software Foundation; version 2 of the License.
>//
>// FRYSK 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
>// General Public License for more details.
>// 
>// You should have received a copy of the GNU General Public License
>// along with FRYSK; if not, write to the Free Software Foundation,
>// Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
>// 
>// In addition, as a special exception, Red Hat, Inc. gives You the
>// additional right to link the code of FRYSK with code not covered
>// under the GNU General Public License ("Non-GPL Code") and to
>// distribute linked combinations including the two, subject to the
>// limitations in this paragraph. Non-GPL Code permitted under this
>// exception must only link to the code of FRYSK through those well
>// defined interfaces identified in the file named EXCEPTION found in
>// the source code files (the "Approved Interfaces"). The files of
>// Non-GPL Code may instantiate templates or use macros or inline
>// functions from the Approved Interfaces without causing the
>// resulting work to be covered by the GNU General Public
>// License. Only Red Hat, Inc. may make changes or additions to the
>// list of Approved Interfaces. You must obey the GNU General Public
>// License in all respects for all of the FRYSK code and other code
>// used in conjunction with FRYSK except the Non-GPL Code covered by
>// this exception. If you modify this file, you may extend this
>// exception to your version of the file, but you are not obligated to
>// do so. If you do not wish to provide this exception without
>// modification, you must delete this exception statement from your
>// version and license this file solely under the GPL without
>// exception.
>
>#include <unistd.h>
>#include <stdlib.h>
>#include <stdio.h>
>#include <sys/ptrace.h>
>#include <sys/types.h>
>#include <sys/user.h>
>#include <sys/wait.h>
>#include <errno.h>
>#include <pthread.h>
>
>// The process id of the child.
>static pid_t pid;
>
>// Whether to stop the child.
>static volatile int stop = 0;
>
>// When the child gets a sig hup we are wrap up and are done.
>static void
>sig_handler(int sig)
>{
>  stop = 1;
>}
>
>// Fork and let the child install signal handlers and do some work
>// while the parent ptraces it.
>int
>main (int argc, char **argv) 
>{
>  pid = fork ();
>  switch (pid)
>    {
>    case -1:
>      {
>	perror ("Error: could not fork child process");
>	exit (1);
>      }
>      
>    case 0:
>      {
>	// Child
>
>	// Setup sighup handler.
>	struct sigaction action;
>	action.sa_handler = sig_handler;
>	sigemptyset (&action.sa_mask);
>	action.sa_flags = 0;
>	sigaction (SIGTRAP, &action, NULL);
>
>	while (! stop)
>	  /* do something useful */ ;
>
>	// Check that handler is still setup correctly.
>	sigaction (SIGTRAP, NULL, &action);
>	if (action.sa_handler == SIG_DFL)
>	  {
>	    printf("SIGTRAP handler reset!");
>	    exit (-1);
>	  }
>
>	// Just for fun, and so our parent can step through the handler.
>	kill (getpid (), SIGTRAP);
>
>	// Check that handler is still setup correctly.
>	sigaction (SIGTRAP, NULL, &action);
>	if (action.sa_handler == SIG_DFL)
>	  {
>	    printf("SIGTRAP handler reset (2)!\n");
>	    exit (-1);
>	  }
>
>	exit (0);
>      }
>
>    default:
>      {
>	// Parent
>	sleep(1);
>
>	long r = ptrace (PTRACE_ATTACH, pid, NULL, NULL);
>	if (r == -1)
>	  {
>	    perror ("Error: could not start trace");
>	    exit (1);
>	  }
>	
>	int status;
>	pid_t waitpid = wait (&status);
>	if (waitpid != pid)
>	  {
>	    perror ("wait didn't return the child pid");
>	    exit (1);
>	  }
>	if (! WIFSTOPPED(status) || WSTOPSIG (status) != SIGSTOP)
>	  {
>	    printf ("child not stopped by SIGSTOP");
>	    exit (1);
>	  }
>
>	// Let the child continue into (and past) the signal handler.
>	r = ptrace (PTRACE_CONT, pid, 0, SIGTRAP);
>	if (r != 0)
>	  {
>	    perror ("ptrace continue into signal handler failed");
>	    exit (1);
>	  }
>
>	// The child will send itself a SIGTRAP now.
>	waitpid = wait (&status);
>	if (waitpid != pid)
>	  {
>	    perror ("wait for signal didn't return the child pid");
>	    exit (1);
>	  }
>	if (! WIFSTOPPED (status) || WSTOPSIG (status) != SIGTRAP)
>	  {
>	    printf ("Child didn't stop with SIGTRAP\n");
>	    exit (1);
>	  }
>
>	// Step into child signal handler.
>	r = ptrace (PTRACE_SINGLESTEP, pid, 0, SIGTRAP);
>	if (r != 0)
>	  {
>	    perror ("ptrace singlestep into signal handler failed");
>	    exit (1);
>	  }
>	waitpid = wait (&status);
>	if (! WIFSTOPPED (status) || WSTOPSIG (status) != SIGTRAP)
>	  {
>	    printf ("child not stop in signal handler with SIGTRAP\n");
>	    exit (1);
>	  }
>
>	// Now single step child to the end
>	do
>	  {
>	    long r = ptrace (PTRACE_SINGLESTEP, pid, 0, 0);
>	    if (r != 0)
>	      {
>		perror( "ptrace singlestepping failed");
>		exit (1);
>	      }
>	     waitpid = wait (&status);
>           }
>	while (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP);
>
>	if (waitpid != pid)
>	  {
>	    perror ("wait after step didn't return the child pid");
>	    exit (1);
>	  }
>	
>	if ( ! WIFEXITED (status) || WEXITSTATUS (status) != 0)
>	  {
>	    printf ("child not properly exited\n");
>	    exit (1);
>	  }
>
>	exit (0); 
>      }
>    }
>}
>

Actions: View

Attachments on bug 227693: 147568