compiler/stdc/setvbuf.c

   1 /*
   2     Copyright © 1995-2012, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     C99 function setvbuf().
   6 */
   7 #include <dos/stdio.h>
   8 #include <proto/dos.h>
   9 #include <errno.h>
  10
  11 #include "__stdio.h"
  12
  13 /*****************************************************************************
  14
  15     NAME */
  16 #include <stdio.h>
  17
  18         int setvbuf (
  19
  20 /*  SYNOPSIS */
  21         FILE *stream,
  22         char *buf,
  23         int mode,
  24         size_t size)
  25
  26 /*  FUNCTION
  27         Sets the buffer and the mode associated with a stream.
  28
  29     INPUTS
  30         stream: stream to set buffer on
  31         buf: the buffer to be associated, when NULL a buffer will be allocated
  32              and freed on close or new setvbuf. Should be longword aligned.
  33         mode: mode for buffering
  34             - _IOFBF: fully buffered
  35             - _IOLBF: line buffered
  36             - _IONBF: Not buffered
  37         size: size of the buffer (needs to be at least 208).
  38
  39     RESULT
  40         0 on succes, EOF on error. errno indicated error.
  41         Function fails when size < 208 and buf != NULL.
  42
  43     NOTES
  44
  45     EXAMPLE
  46
  47     BUGS
  48
  49     SEE ALSO
  50
  51     INTERNALS
  52
  53 ******************************************************************************/
  54 {
  55     if (!stream)
  56     {
  57         errno = EINVAL;
  58         return EOF;
  59     }
  60
  61     /* Pointer has to be longword aligned */
  62     if (buf && (((IPTR)buf & 3) != (IPTR)0))
  63     {
  64         char *buf2 = (char *)(((IPTR)buf | 3) + 1);
  65         size -= buf2 - buf;
  66         buf = buf2;
  67     }
  68     /* Size >= 208 */
  69     if (size < 208)
  70     {
  71         if (buf == NULL)
  72             size = 208;
  73         else
  74             errno = EINVAL;
  75             return EOF;
  76     }
  77
  78     switch (mode)
  79     {
  80     case _IOFBF:
  81         mode = BUF_FULL;
  82         break;
  83     case _IOLBF:
  84         mode = BUF_LINE;
  85         break;
  86     case _IONBF:
  87         mode = BUF_NONE;
  88         break;
  89     default:
  90         errno = EINVAL;
  91         return EOF;
  92     }
  93
  94     return SetVBuf(stream->fh, buf, mode, size ? size : -1);
  95 } /* setvbuf */