stdio/fclose.c

   1 /* Copyright (C) 1991 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
  25
  26 /* Close a stream.  */
  27 int
  28 DEFUN(fclose, (stream), register FILE *stream)
  29 {
  30   int status;
  31
  32   if (stream == NULL)
  33     {
  34       /* Close all streams.  */
  35       register FILE *f;
  36       for (f = __stdio_head; f != NULL; f = f->__next)
  37         if (__validfp(f))
  38           (void) fclose(f);
  39       return 0;
  40     }
  41
  42   if (!__validfp(stream))
  43     {
  44       errno = EINVAL;
  45       return EOF;
  46     }
  47
  48   if (stream->__mode.__write &&
  49       /* Flush the buffer.  */
  50       __flshfp (stream, EOF) == EOF)
  51     return EOF;
  52
  53   /* Free the buffer's storage.  */
  54   if (stream->__buffer != NULL && !stream->__userbuf)
  55     free(stream->__buffer);
  56
  57   /* Close the system file descriptor.  */
  58   if (stream->__io_funcs.__close != NULL)
  59     status = (*stream->__io_funcs.__close)(stream->__cookie);
  60   else if (!stream->__seen && stream->__cookie != NULL)
  61     status = __stdio_close(stream->__cookie);
  62   else
  63     status = 0;
  64
  65   /* Nuke the stream, making it available for re-use.  */
  66   __invalidate(stream);
  67
  68   return status < 0 ? EOF : 0;
  69 }