duma/tests/thread-test.c

/*
 * source URL:
 * http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=67838
 */

/*
 * Author:  Petter Reinholdtsen <pere@hungry.com>
 * Date:    2002-02-13
 * Lisence: GPL
 *
 * Small test program to demonstrate efence crashing on multithreaded
 * programs.
 *
 * Link it like this, and it crashes with segfault.
 *  cc -o efence-thread-test efence-thread-test.c  -lpthread -lefence
 * Remove the -lefence, and it work as it should.
 * The output from gdb when it fails:
 *
 * Program received signal SIGSEGV, Segmentation fault.
 * [Switching to Thread 1026 (LWP 1189)]
 * 0x400382c7 in memalign () from /usr/lib/libefence.so.0
 * (gdb) bt
 * #0  0x400382c7 in memalign () from /usr/lib/libefence.so.0
 * #1  0x4003873c in malloc () from /usr/lib/libefence.so.0
 * #2  0x400a0811 in fopen () from /lib/libc.so.6
 * #3  0x080488e8 in thread_func ()
 * #4  0x40027f0a in pthread_start_thread () from /lib/libpthread.so.0
 * #5  0x40027f51 in pthread_start_thread_event () from /lib/libpthread.so.0
 */

/* check for pthread library */
#if ( !defined( WIN32 ) || defined( __CYGWIN__ ))
#define HAVE_PTHREADS 1
#else  /* if ( !defined( WIN32 ) || defined( __CYGWIN__ )) */
#define HAVE_PTHREADS 0
#endif /* if ( !defined( WIN32 ) || defined( __CYGWIN__ )) */

#include <stdio.h>
#include <stdlib.h>

#if HAVE_PTHREADS

#include "../duma.h"
#include <pthread.h>

static pthread_mutex_t mutex;
static volatile int threads_left = 2;

static void *
thread_func(void *arg)
{
  int i = 2000;
  char *name = (char *)arg;

  while (--i)
  {
    if (pthread_mutex_lock(&mutex))
    {
      fprintf(stderr, "error: %s failed to lock mutex.\n", name);
      exit(1);
    }

    printf("%s : %d\n", name, i);
    if (pthread_mutex_unlock(&mutex))
    {
      fprintf(stderr, "error: %s failed to unlock mutex.\n", name);
      exit(1);
    }

    {
      /* Try to trigger efence error */
      FILE *fp = fopen("/etc/resolv.conf", "r");
      if (NULL != fp)
      {
        char buf[1024];
        fread(buf, sizeof ( buf ), 1, fp);
        fclose(fp);
      }
    }
  }
  --threads_left;
  return ( NULL );
}

static void *
idle_func(void *arg)
{
  (void)arg;

  while (threads_left)
  {
    ;
  }

  /* NOTREACHED */
  return ( NULL );
}

int
main(int argc, char **argv)
{
  pthread_t hello_thread, goodbye_thread;

  (void)argc;
  (void)argv;

  pthread_mutex_init(&mutex, NULL);

  if (pthread_create(&hello_thread, NULL, thread_func, (void *)"hello"))
  {
    fprintf(stderr, "Failed to create hello thread\n");
    exit(1);
  }

  if (pthread_create(&goodbye_thread, NULL, thread_func, (void *)"goodbye"))
  {
    fprintf(stderr, "Failed to create goodbye thread\n");
    exit(1);
  }

  idle_func(NULL);

  pthread_mutex_destroy(&mutex);

  /* NOTREACHED */
  return ( 0 );
}

#else  /* if HAVE_PTHREADS */

int
main(int argc, char **argv)
{
  (void)argc;
  (void)argv;

  printf("Test not implemented for Win32 and Mingw\n");
  return ( 0 );
}

#endif /* if HAVE_PTHREADS */