stdio/fclose.c

   1 /* Copyright (C) 1991, 1995 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
  16 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
  17 Cambridge, MA 02139, USA.  */
  18
  19 #include <ansidecl.h>
  20 #include <stddef.h>
  21 #include <stdio.h>
  22 #include <stdlib.h>
  23 #include <string.h>
  24 #include <errno.h>
  25
  26
  27 /* Close a stream.  */
  28 int
  29 DEFUN(fclose, (stream), register FILE *stream)
  30 {
  31   int status;
  32
  33   if (stream == NULL)
  34     {
  35       /* Close all streams.  */
  36       register FILE *f;
  37       for (f = __stdio_head; f != NULL; f = f->__next)
  38         if (__validfp(f))
  39           (void) fclose(f);
  40       return 0;
  41     }
  42
  43   if (!__validfp(stream))
  44     {
  45       errno = EINVAL;
  46       return EOF;
  47     }
  48
  49   if (stream->__mode.__write &&
  50       /* Flush the buffer.  */
  51       __flshfp (stream, EOF) == EOF)
  52     return EOF;
  53
  54   /* Free the buffer's storage.  */
  55   if (stream->__buffer != NULL && !stream->__userbuf)
  56     free(stream->__buffer);
  57
  58   /* Close the system file descriptor.  */
  59   if (stream->__io_funcs.__close != NULL)
  60     status = (*stream->__io_funcs.__close)(stream->__cookie);
  61   else if (!stream->__seen && stream->__cookie != NULL)
  62     status = __stdio_close(stream->__cookie);
  63   else
  64     status = 0;
  65
  66   /* Nuke the stream, making it available for re-use.  */
  67   __invalidate(stream);
  68
  69   return status < 0 ? EOF : 0;
  70 }