1  /* Utilities for reading/writing fstab, mtab, etc.
       2     Copyright (C) 1995-2023 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 <mntent.h>
      20  #include <stdlib.h>
      21  #include <allocate_once.h>
      22  #include <set-freeres.h>
      23  
      24  struct mntent_buffer
      25  {
      26    struct mntent m;
      27    char buffer[4096];
      28  };
      29  
      30  /* We don't want to allocate the static buffer all the time since it
      31     is not always used (in fact, rather infrequently).  */
      32  static void *mntent_buffer;
      33  
      34  static void *
      35  allocate (void *closure)
      36  {
      37    return malloc (sizeof (struct mntent_buffer));
      38  }
      39  
      40  static void
      41  deallocate (void *closure, void *ptr)
      42  {
      43    free (ptr);
      44  }
      45  
      46  struct mntent *
      47  getmntent (FILE *stream)
      48  {
      49    struct mntent_buffer *buffer = allocate_once (&mntent_buffer,
      50  						allocate, deallocate, NULL);
      51    if (buffer == NULL)
      52      /* If no core is available we don't have a chance to run the
      53         program successfully and so returning NULL is an acceptable
      54         result.  */
      55      return NULL;
      56  
      57    return __getmntent_r (stream, &buffer->m,
      58  			buffer->buffer, sizeof (buffer->buffer));
      59  }
      60  
      61  weak_alias (mntent_buffer, __libc_mntent_freemem_ptr)