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/* No user fns here. Pesch 15apr92. */
/*
* Copyright (c) 1990 The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted
* provided that the above copyright notice and this paragraph are
* duplicated in all such forms and that any documentation,
* advertising materials, and other materials related to such
* distribution and use acknowledge that the software was developed
* by the University of California, Berkeley. The name of the
* University may not be used to endorse or promote products derived
* from this software without specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "%W% (Berkeley) %G%";
#endif /* LIBC_SCCS and not lint */
#include <stdio.h>
#include "local.h"
#include "fvwrite.h"
/*
* Write the given character into the (probably full) buffer for
* the given file. Flush the buffer out if it is or becomes full,
* or if c=='\n' and the file is line buffered.
*/
int
__swbuf (c, fp)
register int c;
register FILE *fp;
{
register int n;
/* Ensure stdio has been initialized. */
CHECK_INIT (fp);
/*
* In case we cannot write, or longjmp takes us out early,
* make sure _w is 0 (if fully- or un-buffered) or -_bf._size
* (if line buffered) so that we will get called again.
* If we did not do this, a sufficient number of putc()
* calls might wrap _w from negative to positive.
*/
fp->_w = fp->_lbfsize;
if (cantwrite (fp))
return EOF;
c = (unsigned char) c;
/*
* If it is completely full, flush it out. Then, in any case,
* stuff c into the buffer. If this causes the buffer to fill
* completely, or if c is '\n' and the file is line buffered,
* flush it (perhaps a second time). The second flush will always
* happen on unbuffered streams, where _bf._size==1; fflush()
* guarantees that putc() will always call wbuf() by setting _w
* to 0, so we need not do anything else.
*/
n = fp->_p - fp->_bf._base;
if (n >= fp->_bf._size)
{
if (fflush (fp))
return EOF;
n = 0;
}
fp->_w--;
*fp->_p++ = c;
if (++n == fp->_bf._size || (fp->_flags & __SLBF && c == '\n'))
if (fflush (fp))
return EOF;
return c;
}
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