11573Srgrimes/*- 21573Srgrimes * Copyright (c) 1990, 1993 31573Srgrimes * The Regents of the University of California. All rights reserved. 41573Srgrimes * 51573Srgrimes * This code is derived from software contributed to Berkeley by 61573Srgrimes * Chris Torek. 71573Srgrimes * 81573Srgrimes * Redistribution and use in source and binary forms, with or without 91573Srgrimes * modification, are permitted provided that the following conditions 101573Srgrimes * are met: 111573Srgrimes * 1. Redistributions of source code must retain the above copyright 121573Srgrimes * notice, this list of conditions and the following disclaimer. 131573Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 141573Srgrimes * notice, this list of conditions and the following disclaimer in the 151573Srgrimes * documentation and/or other materials provided with the distribution. 16249808Semaste * 3. Neither the name of the University nor the names of its contributors 171573Srgrimes * may be used to endorse or promote products derived from this software 181573Srgrimes * without specific prior written permission. 191573Srgrimes * 201573Srgrimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 211573Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 221573Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 231573Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 241573Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 251573Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 261573Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 271573Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 281573Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 291573Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 301573Srgrimes * SUCH DAMAGE. 311573Srgrimes */ 321573Srgrimes 331573Srgrimes#if defined(LIBC_SCCS) && !defined(lint) 341573Srgrimesstatic char sccsid[] = "@(#)wbuf.c 8.1 (Berkeley) 6/4/93"; 351573Srgrimes#endif /* LIBC_SCCS and not lint */ 3692986Sobrien#include <sys/cdefs.h> 3792986Sobrien__FBSDID("$FreeBSD$"); 381573Srgrimes 39269482Spfg#include <errno.h> 401573Srgrimes#include <stdio.h> 411573Srgrimes#include "local.h" 421573Srgrimes 431573Srgrimes/* 441573Srgrimes * Write the given character into the (probably full) buffer for 451573Srgrimes * the given file. Flush the buffer out if it is or becomes full, 461573Srgrimes * or if c=='\n' and the file is line buffered. 4771579Sdeischen * 4871579Sdeischen * Non-MT-safe 491573Srgrimes */ 5016586Sjraynardint 51249810Semaste__swbuf(int c, FILE *fp) 521573Srgrimes{ 5392889Sobrien int n; 541573Srgrimes 551573Srgrimes /* 561573Srgrimes * In case we cannot write, or longjmp takes us out early, 571573Srgrimes * make sure _w is 0 (if fully- or un-buffered) or -_bf._size 581573Srgrimes * (if line buffered) so that we will get called again. 591573Srgrimes * If we did not do this, a sufficient number of putc() 601573Srgrimes * calls might wrap _w from negative to positive. 611573Srgrimes */ 621573Srgrimes fp->_w = fp->_lbfsize; 63269482Spfg if (prepwrite(fp) != 0) { 64269482Spfg errno = EBADF; 651573Srgrimes return (EOF); 66269482Spfg } 671573Srgrimes c = (unsigned char)c; 681573Srgrimes 69101776Stjr ORIENT(fp, -1); 70101776Stjr 711573Srgrimes /* 721573Srgrimes * If it is completely full, flush it out. Then, in any case, 731573Srgrimes * stuff c into the buffer. If this causes the buffer to fill 741573Srgrimes * completely, or if c is '\n' and the file is line buffered, 751573Srgrimes * flush it (perhaps a second time). The second flush will always 761573Srgrimes * happen on unbuffered streams, where _bf._size==1; fflush() 771573Srgrimes * guarantees that putc() will always call wbuf() by setting _w 781573Srgrimes * to 0, so we need not do anything else. 791573Srgrimes */ 801573Srgrimes n = fp->_p - fp->_bf._base; 811573Srgrimes if (n >= fp->_bf._size) { 8271579Sdeischen if (__fflush(fp)) 831573Srgrimes return (EOF); 841573Srgrimes n = 0; 851573Srgrimes } 861573Srgrimes fp->_w--; 871573Srgrimes *fp->_p++ = c; 881573Srgrimes if (++n == fp->_bf._size || (fp->_flags & __SLBF && c == '\n')) 8971579Sdeischen if (__fflush(fp)) 901573Srgrimes return (EOF); 911573Srgrimes return (c); 921573Srgrimes} 93