1  /* Test for shm_open cancellation handling: BZ #18243.
       2     Copyright (C) 2016-2023 Free Software Foundation, Inc.
       3     This file is part of the GNU C Library.
       4  
       5     The GNU C Library is free software; you can redistribute it and/or
       6     modify it under the terms of the GNU Lesser General Public
       7     License as published by the Free Software Foundation; either
       8     version 2.1 of the License, or (at your option) any later version.
       9  
      10     The GNU C Library is distributed in the hope that it will be useful,
      11     but WITHOUT ANY WARRANTY; without even the implied warranty of
      12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      13     Lesser General Public License for more details.
      14  
      15     You should have received a copy of the GNU Lesser General Public
      16     License along with the GNU C Library; if not, see
      17     <https://www.gnu.org/licenses/>.  */
      18  
      19  #include <pthread.h>
      20  #include <sys/mman.h>
      21  #include <semaphore.h>
      22  #include <stdio.h>
      23  #include <fcntl.h>
      24  #include <unistd.h>
      25  #include <errno.h>
      26  #include <stdlib.h>
      27  
      28  static sem_t sem;	/* Use to sync with thread start.  */
      29  static char shm_name[sizeof "/glibc-shm_open-cancel-" + sizeof (pid_t) * 3];
      30  
      31  static void
      32  init_shm_name (void)
      33  {
      34    snprintf (shm_name, sizeof (shm_name), "/glibc-shm_open-cancel-%u",
      35  	    getpid ());
      36  }
      37  
      38  static void
      39  remove_shm (int status, void *arg)
      40  {
      41    shm_unlink (shm_name);
      42  }
      43  
      44  static void *
      45  tf (void *arg)
      46  {
      47    pthread_setcancelstate (PTHREAD_CANCEL_DISABLE, 0);
      48  
      49    if (sem_wait (&sem) != 0)
      50      {
      51        printf ("error: sem_wait failed: %m");
      52        exit (1);
      53      }
      54  
      55    if (pthread_setcancelstate (PTHREAD_CANCEL_ENABLE, 0) != 0)
      56      {
      57        printf ("error: pthread_setcancelstate failed: %m");
      58        exit (1);
      59      }
      60  
      61    /* Neither sem_unlink or sem_open should act on thread cancellation.  */
      62    shm_unlink (shm_name);
      63    on_exit (remove_shm, NULL);
      64  
      65    int fd = shm_open (shm_name, O_CREAT, 0600);
      66    if (fd == -1)
      67      {
      68        int exit_code;
      69        if (errno == ENOSYS || errno == EACCES)
      70  	exit_code = 77;
      71        else
      72  	exit_code = 1;
      73        exit (exit_code);
      74      }
      75  
      76    if (pthread_setcancelstate (PTHREAD_CANCEL_DISABLE, 0) != 0)
      77      {
      78        printf ("error: pthread_setcancelstate failed: %m");
      79        exit (1);
      80      }
      81  
      82    if (close (fd) != 0)
      83      {
      84        printf ("error: pthread_setcancelstate failed: %m");
      85        exit (1);
      86      }
      87  
      88    return NULL;
      89  }
      90  
      91  static int
      92  do_test (void)
      93  {
      94    pthread_t td;
      95  
      96    init_shm_name ();
      97  
      98    if (sem_init (&sem, 0, 0))
      99      {
     100        printf ("error: sem_init failed: %m\n");
     101        exit (1);
     102      }
     103  
     104    if (pthread_create (&td, NULL, tf, NULL) != 0)
     105      {
     106        printf ("error: pthread_create failed: %m\n");
     107        exit (1);
     108      }
     109  
     110    if (pthread_cancel (td) != 0)
     111      {
     112        printf ("error: pthread_cancel failed: %m\n");
     113        exit (1);
     114      }
     115  
     116    if (sem_post (&sem) != 0)
     117      {
     118        printf ("error: sem_post failed: %m\n");
     119        exit (1);
     120      }
     121  
     122    void *r;
     123    if (pthread_join (td, &r) != 0)
     124      {
     125        printf ("error: pthread_join failed: %m\n");
     126        exit (1);
     127      }
     128  
     129    if (r == PTHREAD_CANCELED)
     130      {
     131        puts ("error: pthread_join returned PTHREAD_CANCELED");
     132        exit (1);
     133      }
     134  
     135    return 0;
     136  }
     137  
     138  #define TEST_FUNCTION do_test ()
     139  #include <test-skeleton.c>