compiler/clib/close.c

   1 /*
   2     Copyright © 1995-2003, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     ANSI C function close().
   6 */
   7
   8 #include "__arosc_privdata.h"
   9
  10 #include <unistd.h>
  11 #include <stdlib.h>
  12 #include <proto/exec.h>
  13 #include <proto/dos.h>
  14 #include <errno.h>
  15 #include "__open.h"
  16 #include "__errno.h"
  17
  18 /*****************************************************************************
  19
  20     NAME */
  21 #include <unistd.h>
  22
  23         int close (
  24
  25 /*  SYNOPSIS */
  26         int fd)
  27
  28 /*  FUNCTION
  29         Closes an open file. If this is the last file descriptor
  30         associated with this file, then all allocated resources
  31         are freed, too.
  32
  33     INPUTS
  34         fd - The result of a successful open()
  35
  36     RESULT
  37         -1 for error or zero on success.
  38
  39     NOTES
  40         This function must not be used in a shared library or
  41         in a threaded application.
  42
  43     EXAMPLE
  44
  45     BUGS
  46
  47     SEE ALSO
  48         open(), read(), write(), fopen()
  49
  50     INTERNALS
  51
  52 ******************************************************************************/
  53 {
  54     fdesc *fdesc;
  55     AROS_GET_SYSBASE_OK
  56     AROS_GET_DOSBASE
  57
  58     if (!(fdesc = __getfdesc(fd)))
  59     {
  60         errno = EBADF;
  61
  62         return -1;
  63     }
  64
  65     if (--fdesc->opencount == 0)
  66     {
  67         /* Due to a *stupid* behaviour of the dos.library we cannot handle closing failures cleanly :-(
  68         if (
  69             fdesc->fh!=__stdfiles[STDIN_FILENO] &&
  70             fdesc->fh!=__stdfiles[STDOUT_FILENO] &&
  71             fdesc->fh!=__stdfiles[STDERR_FILENO] &&
  72             !Close(fdesc->fh)
  73         )
  74         {
  75             fdesc->opencount++;
  76             errno = IoErr2errno(IoErr());
  77
  78             return -1;
  79         }
  80         */
  81 #warning Damn dos.library! We cannot report the error code correctly! This oughta change someday...
  82         /* Since the dos.library destroyes the file handle anyway, even if the closing fails, we cannot
  83            report the error code correctly, so just close the file and get out of here */
  84
  85         if
  86         (
  87             fdesc->fh!=__stdfiles[STDIN_FILENO] &&
  88             fdesc->fh!=__stdfiles[STDOUT_FILENO] &&
  89             fdesc->fh!=__stdfiles[STDERR_FILENO]
  90         )
  91         {
  92             (void)Close(fdesc->fh);
  93         }
  94
  95         free(fdesc);
  96     }
  97
  98     __setfdesc(fd, NULL);
  99
 100     return 0;
 101 } /* close */
 102