xref: /freebsd/lib/libc/stdio/ungetwc.c (revision d8f77b45290fd175d136d87aa80b6dea46c483fe)
1e74101e4STim J. Robbins /*-
287275e43STim J. Robbins  * Copyright (c) 2002-2004 Tim J. Robbins.
3e74101e4STim J. Robbins  * All rights reserved.
4e74101e4STim J. Robbins  *
5e74101e4STim J. Robbins  * Redistribution and use in source and binary forms, with or without
6e74101e4STim J. Robbins  * modification, are permitted provided that the following conditions
7e74101e4STim J. Robbins  * are met:
8e74101e4STim J. Robbins  * 1. Redistributions of source code must retain the above copyright
9e74101e4STim J. Robbins  *    notice, this list of conditions and the following disclaimer.
10e74101e4STim J. Robbins  * 2. Redistributions in binary form must reproduce the above copyright
11e74101e4STim J. Robbins  *    notice, this list of conditions and the following disclaimer in the
12e74101e4STim J. Robbins  *    documentation and/or other materials provided with the distribution.
13e74101e4STim J. Robbins  *
14e74101e4STim J. Robbins  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15e74101e4STim J. Robbins  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16e74101e4STim J. Robbins  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17e74101e4STim J. Robbins  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18e74101e4STim J. Robbins  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19e74101e4STim J. Robbins  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20e74101e4STim J. Robbins  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21e74101e4STim J. Robbins  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22e74101e4STim J. Robbins  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23e74101e4STim J. Robbins  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24e74101e4STim J. Robbins  * SUCH DAMAGE.
25e74101e4STim J. Robbins  */
26e74101e4STim J. Robbins 
27e74101e4STim J. Robbins #include <sys/cdefs.h>
28e74101e4STim J. Robbins __FBSDID("$FreeBSD$");
29e74101e4STim J. Robbins 
30e74101e4STim J. Robbins #include "namespace.h"
31e74101e4STim J. Robbins #include <errno.h>
32d8f77b45SStefan Farfeleder #include <limits.h>
33e74101e4STim J. Robbins #include <stdio.h>
3424990dfaSTim J. Robbins #include <stdlib.h>
35e74101e4STim J. Robbins #include <wchar.h>
36e74101e4STim J. Robbins #include "un-namespace.h"
37e74101e4STim J. Robbins #include "libc_private.h"
38e74101e4STim J. Robbins #include "local.h"
39f9ceea9bSTim J. Robbins #include "mblocal.h"
40e74101e4STim J. Robbins 
415f147b57STim J. Robbins /*
425f147b57STim J. Robbins  * Non-MT-safe version.
435f147b57STim J. Robbins  */
44e74101e4STim J. Robbins wint_t
455f147b57STim J. Robbins __ungetwc(wint_t wc, FILE *fp)
46e74101e4STim J. Robbins {
4724990dfaSTim J. Robbins 	char buf[MB_LEN_MAX];
4824990dfaSTim J. Robbins 	size_t len;
49e74101e4STim J. Robbins 
5024990dfaSTim J. Robbins 	if (wc == WEOF)
515f147b57STim J. Robbins 		return (WEOF);
52f9ceea9bSTim J. Robbins 	if ((len = __wcrtomb(buf, wc, &fp->_extra->mbstate)) == (size_t)-1) {
536180233fSTim J. Robbins 		fp->_flags |= __SERR;
545f147b57STim J. Robbins 		return (WEOF);
556180233fSTim J. Robbins 	}
5624990dfaSTim J. Robbins 	while (len-- != 0)
5792603416STim J. Robbins 		if (__ungetc((unsigned char)buf[len], fp) == EOF)
585f147b57STim J. Robbins 			return (WEOF);
5924990dfaSTim J. Robbins 
6024990dfaSTim J. Robbins 	return (wc);
615f147b57STim J. Robbins }
6292603416STim J. Robbins 
635f147b57STim J. Robbins /*
645f147b57STim J. Robbins  * MT-safe version.
655f147b57STim J. Robbins  */
665f147b57STim J. Robbins wint_t
675f147b57STim J. Robbins ungetwc(wint_t wc, FILE *fp)
685f147b57STim J. Robbins {
695f147b57STim J. Robbins 	wint_t r;
705f147b57STim J. Robbins 
715f147b57STim J. Robbins 	FLOCKFILE(fp);
725f147b57STim J. Robbins 	ORIENT(fp, 1);
735f147b57STim J. Robbins 	r = __ungetwc(wc, fp);
7492603416STim J. Robbins 	FUNLOCKFILE(fp);
755f147b57STim J. Robbins 
765f147b57STim J. Robbins 	return (r);
77e74101e4STim J. Robbins }
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