sysdeps/mach/hurd/tmpfile.c

   1 /* Open a stdio stream on an anonymous temporary file.  Hurd version.
   2    Copyright (C) 2001,2002,2003 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, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #include <stdio.h>
  21 #include <hurd.h>
  22 #include <hurd/fs.h>
  23 #include <hurd/fd.h>
  24 #include <fcntl.h>
  25 #include <unistd.h>
  26 #include <iolibio.h>
  27
  28 /* This returns a new stream opened on a temporary file (generated
  29    by tmpnam).  The file is opened with mode "w+b" (binary read/write).
  30    If we couldn't generate a unique filename or the file couldn't
  31    be opened, NULL is returned.  */
  32 FILE *
  33 __tmpfile (void)
  34 {
  35   error_t err;
  36   file_t file;
  37   int fd;
  38   FILE *f;
  39
  40   /* Get a port to the directory that will contain the file.  */
  41   const char *dirname = __secure_getenv ("TMPDIR") ?: P_tmpdir;
  42   file_t dir = __file_name_lookup (dirname, 0, 0);
  43   if (dir == MACH_PORT_NULL)
  44     return NULL;
  45
  46   /* Create an unnamed file in the temporary directory.  */
  47   err = __dir_mkfile (dir, O_RDWR, S_IRUSR | S_IWUSR, &file);
  48   __mach_port_deallocate (__mach_task_self (), dir);
  49   if (err)
  50     return __hurd_fail (err), NULL;
  51
  52   /* Get a file descriptor for that port.  POSIX.1 requires that streams
  53      returned by tmpfile allocate file descriptors as fopen would.  */
  54   fd = _hurd_intern_fd (file, O_RDWR, 1); /* dealloc on error */
  55   if (fd < 0)
  56     return NULL;
  57
  58   /* Open a stream on the unnamed file.
  59      It will cease to exist when this stream is closed.  */
  60   if ((f = INTUSE(_IO_fdopen) (fd, "w+b")) == NULL)
  61     __close (fd);
  62
  63   return f;
  64 }
  65
  66 #include <shlib-compat.h>
  67 versioned_symbol (libc, __tmpfile, tmpfile, GLIBC_2_1);
  68
  69 weak_alias (__tmpfile, tmpfile64)