sysdeps/mach/hurd/stdio_init.c

   1 /* Copyright (C) 1995, 1997 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Library General Public License as
   6    published by the Free Software Foundation; either version 2 of the
   7    License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Library General Public License for more details.
  13
  14    You should have received a copy of the GNU Library General Public
  15    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  16    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17    Boston, MA 02111-1307, USA.  */
  18
  19 #include <stdio.h>
  20 #include <sys/types.h>
  21 #include <sys/stat.h>
  22 #include <unistd.h>
  23 #include <hurd/fd.h>
  24 #include <hurd/io.h>
  25 #include <hurd/term.h>
  26
  27 /* Initialize STREAM as necessary.
  28    This may change I/O functions, give a buffer, etc.
  29    If no buffer is allocated, but the bufsize is set,
  30    the bufsize will be used to allocate the buffer.  */
  31 void
  32 __stdio_init_stream (stream)
  33      FILE *stream;
  34 {
  35   struct hurd_fd *const d = stream->__cookie;
  36   struct stat statb;
  37   error_t err;
  38
  39   if (stream->__buffer != NULL || stream->__userbuf)
  40     /* If's unbuffered by request, we can't do anything useful.  */
  41     return;
  42
  43   /* Find out what sort of file this is.  */
  44   if (err = HURD_FD_PORT_USE (d, __io_stat (port, &statb)))
  45     return;
  46
  47   if (S_ISCHR (statb.st_mode))
  48     {
  49       /* It's a character device.
  50          Make it line-buffered if it's a terminal.  */
  51       mach_port_t cttyid;
  52       err = HURD_FD_PORT_USE (d, __term_getctty (port, &cttyid));
  53       if (! err)
  54         {
  55           __mach_port_deallocate (__mach_task_self (), cttyid);
  56           stream->__linebuf = 1;
  57         }
  58     }
  59
  60   /* Use the block-size field to determine
  61      the system's optimal buffering size.  */
  62   stream->__bufsize = statb.st_blksize;
  63 }