tmpfile.c

Glibc 2.3.2源代码(解压后有100多M)

/* Open a stdio stream on an anonymous temporary file.  Hurd version.
   Copyright (C) 2001,02 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Lesser General Public
   License as published by the Free Software Foundation; either
   version 2.1 of the License, or (at your option) any later version.

   The GNU C Library 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
   Lesser General Public License for more details.

   You should have received a copy of the GNU Lesser General Public
   License along with the GNU C Library; if not, write to the Free
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307 USA.  */

#include <stdio.h>
#include <hurd.h>
#include <hurd/fs.h>
#include <hurd/fd.h>
#include <fcntl.h>
#include <unistd.h>

#ifdef USE_IN_LIBIO
# include <iolibio.h>
# define __fdopen INTUSE(_IO_fdopen)
# define tmpfile __new_tmpfile
#endif

/* This returns a new stream opened on a temporary file (generated
   by tmpnam).  The file is opened with mode "w+b" (binary read/write).
   If we couldn't generate a unique filename or the file couldn't
   be opened, NULL is returned.  */
FILE *
tmpfile (void)
{
  error_t err;
  file_t file;
  int fd;
  FILE *f;

  /* Get a port to the directory that will contain the file.  */
  const char *dirname = __secure_getenv ("TMPDIR") ?: P_tmpdir;
  file_t dir = __file_name_lookup (dirname, 0, 0);
  if (dir == MACH_PORT_NULL)
    return NULL;

  /* Create an unnamed file in the temporary directory.  */
  err = __dir_mkfile (dir, O_RDWR, S_IRUSR | S_IWUSR, &file);
  __mach_port_deallocate (__mach_task_self (), dir);
  if (err)
    return __hurd_fail (err), NULL;

  /* Get a file descriptor for that port.  POSIX.1 requires that streams
     returned by tmpfile allocate file descriptors as fopen would.  */
  fd = _hurd_intern_fd (file, O_RDWR, 1); /* dealloc on error */
  if (fd < 0)
    return NULL;

  /* Open a stream on the unnamed file.
     It will cease to exist when this stream is closed.  */
  if ((f = __fdopen (fd, "w+b")) == NULL)
    __close (fd);

  return f;
}

#ifdef USE_IN_LIBIO
# undef tmpfile
# include <shlib-compat.h>
versioned_symbol (libc, __new_tmpfile, tmpfile, GLIBC_2_1);
#endif

weak_alias (tmpfile, tmpfile64)