BizHawk/waterbox/libc/functions/stdio/_PDCLIB_prepwrite.c

43 lines
1.0 KiB
C

/* _PDCLIB_prepwrite( FILE * )
This file is part of the Public Domain C Library (PDCLib).
Permission is granted to use, modify, and / or redistribute at will.
*/
#include <stdio.h>
#include <errno.h>
#ifndef REGTEST
#include "_PDCLIB_io.h"
int _PDCLIB_prepwrite( FILE * stream )
{
if ( ( stream->bufidx < stream->bufend ) || ( stream->ungetidx > 0 ) ||
( stream->status & ( _PDCLIB_FREAD | _PDCLIB_ERRORFLAG | _PDCLIB_WIDESTREAM | _PDCLIB_EOFFLAG ) ) ||
! ( stream->status & ( _PDCLIB_FWRITE | _PDCLIB_FAPPEND | _PDCLIB_FRW ) ) )
{
/* Function called on illegal (e.g. input) stream.
See the comments on implementation-defined errno values in
<_PDCLIB_config.h>.
*/
errno = EINVAL;
stream->status |= _PDCLIB_ERRORFLAG;
return EOF;
}
stream->status |= _PDCLIB_FWRITE | _PDCLIB_BYTESTREAM;
return 0;
}
#endif
#ifdef TEST
#include "_PDCLIB_test.h"
int main( void )
{
/* Testing covered by ftell.c */
return TEST_RESULTS;
}
#endif