1*f14fb602SLionel Sambuc /* $NetBSD: wbuf.c,v 1.15 2012/03/15 18:22:31 christos Exp $ */
22fe8fb19SBen Gras
32fe8fb19SBen Gras /*-
42fe8fb19SBen Gras * Copyright (c) 1990, 1993
52fe8fb19SBen Gras * The Regents of the University of California. All rights reserved.
62fe8fb19SBen Gras *
72fe8fb19SBen Gras * This code is derived from software contributed to Berkeley by
82fe8fb19SBen Gras * Chris Torek.
92fe8fb19SBen Gras *
102fe8fb19SBen Gras * Redistribution and use in source and binary forms, with or without
112fe8fb19SBen Gras * modification, are permitted provided that the following conditions
122fe8fb19SBen Gras * are met:
132fe8fb19SBen Gras * 1. Redistributions of source code must retain the above copyright
142fe8fb19SBen Gras * notice, this list of conditions and the following disclaimer.
152fe8fb19SBen Gras * 2. Redistributions in binary form must reproduce the above copyright
162fe8fb19SBen Gras * notice, this list of conditions and the following disclaimer in the
172fe8fb19SBen Gras * documentation and/or other materials provided with the distribution.
182fe8fb19SBen Gras * 3. Neither the name of the University nor the names of its contributors
192fe8fb19SBen Gras * may be used to endorse or promote products derived from this software
202fe8fb19SBen Gras * without specific prior written permission.
212fe8fb19SBen Gras *
222fe8fb19SBen Gras * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
232fe8fb19SBen Gras * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
242fe8fb19SBen Gras * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
252fe8fb19SBen Gras * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
262fe8fb19SBen Gras * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
272fe8fb19SBen Gras * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
282fe8fb19SBen Gras * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
292fe8fb19SBen Gras * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
302fe8fb19SBen Gras * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
312fe8fb19SBen Gras * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
322fe8fb19SBen Gras * SUCH DAMAGE.
332fe8fb19SBen Gras */
342fe8fb19SBen Gras
352fe8fb19SBen Gras #include <sys/cdefs.h>
362fe8fb19SBen Gras #if defined(LIBC_SCCS) && !defined(lint)
372fe8fb19SBen Gras #if 0
382fe8fb19SBen Gras static char sccsid[] = "@(#)wbuf.c 8.1 (Berkeley) 6/4/93";
392fe8fb19SBen Gras #else
40*f14fb602SLionel Sambuc __RCSID("$NetBSD: wbuf.c,v 1.15 2012/03/15 18:22:31 christos Exp $");
412fe8fb19SBen Gras #endif
422fe8fb19SBen Gras #endif /* LIBC_SCCS and not lint */
432fe8fb19SBen Gras
442fe8fb19SBen Gras #include <assert.h>
452fe8fb19SBen Gras #include <errno.h>
462fe8fb19SBen Gras #include <stdio.h>
472fe8fb19SBen Gras #include "reentrant.h"
482fe8fb19SBen Gras #include "local.h"
492fe8fb19SBen Gras
502fe8fb19SBen Gras /*
512fe8fb19SBen Gras * Write the given character into the (probably full) buffer for
522fe8fb19SBen Gras * the given file. Flush the buffer out if it is or becomes full,
532fe8fb19SBen Gras * or if c=='\n' and the file is line buffered.
542fe8fb19SBen Gras */
552fe8fb19SBen Gras int
__swbuf(int c,FILE * fp)56*f14fb602SLionel Sambuc __swbuf(int c, FILE *fp)
572fe8fb19SBen Gras {
582fe8fb19SBen Gras int n;
592fe8fb19SBen Gras
602fe8fb19SBen Gras _DIAGASSERT(fp != NULL);
612fe8fb19SBen Gras
622fe8fb19SBen Gras _SET_ORIENTATION(fp, -1);
632fe8fb19SBen Gras
642fe8fb19SBen Gras /*
652fe8fb19SBen Gras * In case we cannot write, or longjmp takes us out early,
662fe8fb19SBen Gras * make sure _w is 0 (if fully- or un-buffered) or -_bf._size
672fe8fb19SBen Gras * (if line buffered) so that we will get called again.
682fe8fb19SBen Gras * If we did not do this, a sufficient number of putc()
692fe8fb19SBen Gras * calls might wrap _w from negative to positive.
702fe8fb19SBen Gras */
712fe8fb19SBen Gras fp->_w = fp->_lbfsize;
722fe8fb19SBen Gras if (cantwrite(fp)) {
732fe8fb19SBen Gras errno = EBADF;
74*f14fb602SLionel Sambuc return EOF;
752fe8fb19SBen Gras }
762fe8fb19SBen Gras c = (unsigned char)c;
772fe8fb19SBen Gras
782fe8fb19SBen Gras /*
792fe8fb19SBen Gras * If it is completely full, flush it out. Then, in any case,
802fe8fb19SBen Gras * stuff c into the buffer. If this causes the buffer to fill
812fe8fb19SBen Gras * completely, or if c is '\n' and the file is line buffered,
822fe8fb19SBen Gras * flush it (perhaps a second time). The second flush will always
832fe8fb19SBen Gras * happen on unbuffered streams, where _bf._size==1; fflush()
842fe8fb19SBen Gras * guarantees that putc() will always call wbuf() by setting _w
852fe8fb19SBen Gras * to 0, so we need not do anything else.
862fe8fb19SBen Gras */
87*f14fb602SLionel Sambuc _DIAGASSERT(__type_fit(int, fp->_p - fp->_bf._base));
88*f14fb602SLionel Sambuc n = (int)(fp->_p - fp->_bf._base);
892fe8fb19SBen Gras if (n >= fp->_bf._size) {
902fe8fb19SBen Gras if (fflush(fp))
91*f14fb602SLionel Sambuc return EOF;
922fe8fb19SBen Gras n = 0;
932fe8fb19SBen Gras }
942fe8fb19SBen Gras fp->_w--;
952fe8fb19SBen Gras *fp->_p++ = c;
962fe8fb19SBen Gras if (++n == fp->_bf._size || (fp->_flags & __SLBF && c == '\n'))
972fe8fb19SBen Gras if (fflush(fp))
98*f14fb602SLionel Sambuc return EOF;
99*f14fb602SLionel Sambuc return c;
1002fe8fb19SBen Gras }
101