* Copyright (c) 1990 The Regents of the University of California.
* This code is derived from software contributed to Berkeley by
* %sccs.include.redist.c%
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid
[] = "@(#)wbuf.c 5.6 (Berkeley) %G%";
#endif /* LIBC_SCCS and not lint */
* 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.
* 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.
* 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 (++n
== fp
->_bf
._size
|| (fp
->_flags
& __SLBF
&& c
== '\n'))