ungetwc.c revision 128002
1/*- 2 * Copyright (c) 2002 Tim J. Robbins. 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27#include <sys/cdefs.h> 28__FBSDID("$FreeBSD: head/lib/libc/stdio/ungetwc.c 128002 2004-04-07 09:55:05Z tjr $"); 29 30#include "namespace.h" 31#include <errno.h> 32#include <stdio.h> 33#include <stdlib.h> 34#include <wchar.h> 35#include "un-namespace.h" 36#include "libc_private.h" 37#include "local.h" 38 39/* 40 * Non-MT-safe version. 41 */ 42wint_t 43__ungetwc(wint_t wc, FILE *fp) 44{ 45 static const mbstate_t initial; 46 mbstate_t mbs; 47 char buf[MB_LEN_MAX]; 48 size_t len; 49 50 if (wc == WEOF) 51 return (WEOF); 52 mbs = initial; 53 if ((len = wcrtomb(buf, wc, &mbs)) == (size_t)-1) { 54 fp->_flags |= __SERR; 55 return (WEOF); 56 } 57 while (len-- != 0) 58 if (__ungetc((unsigned char)buf[len], fp) == EOF) 59 return (WEOF); 60 61 return (wc); 62} 63 64/* 65 * MT-safe version. 66 */ 67wint_t 68ungetwc(wint_t wc, FILE *fp) 69{ 70 wint_t r; 71 72 FLOCKFILE(fp); 73 ORIENT(fp, 1); 74 r = __ungetwc(wc, fp); 75 FUNLOCKFILE(fp); 76 77 return (r); 78} 79