xref: /freebsd/lib/libc/stdio/fgetwc.c (revision 3c87aa1d3dc1d8dad3efad322852a8e1e76dee55)
1e74101e4STim J. Robbins /*-
287275e43STim J. Robbins  * Copyright (c) 2002-2004 Tim J. Robbins.
3e74101e4STim J. Robbins  * All rights reserved.
4e74101e4STim J. Robbins  *
5*3c87aa1dSDavid Chisnall  * Copyright (c) 2011 The FreeBSD Foundation
6*3c87aa1dSDavid Chisnall  * All rights reserved.
7*3c87aa1dSDavid Chisnall  * Portions of this software were developed by David Chisnall
8*3c87aa1dSDavid Chisnall  * under sponsorship from the FreeBSD Foundation.
9*3c87aa1dSDavid Chisnall  *
10e74101e4STim J. Robbins  * Redistribution and use in source and binary forms, with or without
11e74101e4STim J. Robbins  * modification, are permitted provided that the following conditions
12e74101e4STim J. Robbins  * are met:
13e74101e4STim J. Robbins  * 1. Redistributions of source code must retain the above copyright
14e74101e4STim J. Robbins  *    notice, this list of conditions and the following disclaimer.
15e74101e4STim J. Robbins  * 2. Redistributions in binary form must reproduce the above copyright
16e74101e4STim J. Robbins  *    notice, this list of conditions and the following disclaimer in the
17e74101e4STim J. Robbins  *    documentation and/or other materials provided with the distribution.
18e74101e4STim J. Robbins  *
19e74101e4STim J. Robbins  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20e74101e4STim J. Robbins  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21e74101e4STim J. Robbins  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22e74101e4STim J. Robbins  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23e74101e4STim J. Robbins  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24e74101e4STim J. Robbins  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25e74101e4STim J. Robbins  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26e74101e4STim J. Robbins  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27e74101e4STim J. Robbins  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28e74101e4STim J. Robbins  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29e74101e4STim J. Robbins  * SUCH DAMAGE.
30e74101e4STim J. Robbins  */
31e74101e4STim J. Robbins 
32e74101e4STim J. Robbins #include <sys/cdefs.h>
33e74101e4STim J. Robbins __FBSDID("$FreeBSD$");
34e74101e4STim J. Robbins 
35e74101e4STim J. Robbins #include "namespace.h"
36e74101e4STim J. Robbins #include <errno.h>
37e74101e4STim J. Robbins #include <stdio.h>
3824990dfaSTim J. Robbins #include <stdlib.h>
39e74101e4STim J. Robbins #include <wchar.h>
40e74101e4STim J. Robbins #include "un-namespace.h"
41e74101e4STim J. Robbins #include "libc_private.h"
42e74101e4STim J. Robbins #include "local.h"
43f9ceea9bSTim J. Robbins #include "mblocal.h"
44*3c87aa1dSDavid Chisnall #include "xlocale_private.h"
45e74101e4STim J. Robbins 
468f030a44STim J. Robbins /*
478f030a44STim J. Robbins  * MT-safe version.
488f030a44STim J. Robbins  */
498f030a44STim J. Robbins wint_t
50*3c87aa1dSDavid Chisnall fgetwc_l(FILE *fp, locale_t locale)
518f030a44STim J. Robbins {
528f030a44STim J. Robbins 	wint_t r;
53*3c87aa1dSDavid Chisnall 	FIX_LOCALE(locale);
548f030a44STim J. Robbins 
558f030a44STim J. Robbins 	FLOCKFILE(fp);
568f030a44STim J. Robbins 	ORIENT(fp, 1);
57*3c87aa1dSDavid Chisnall 	r = __fgetwc(fp, locale);
588f030a44STim J. Robbins 	FUNLOCKFILE(fp);
598f030a44STim J. Robbins 
608f030a44STim J. Robbins 	return (r);
618f030a44STim J. Robbins }
62*3c87aa1dSDavid Chisnall wint_t
63*3c87aa1dSDavid Chisnall fgetwc(FILE *fp)
64*3c87aa1dSDavid Chisnall {
65*3c87aa1dSDavid Chisnall 	return fgetwc_l(fp, __get_locale());
66*3c87aa1dSDavid Chisnall }
678f030a44STim J. Robbins 
68fcc51917STim J. Robbins /*
69fcc51917STim J. Robbins  * Non-MT-safe version.
70fcc51917STim J. Robbins  */
71fcc51917STim J. Robbins wint_t
72*3c87aa1dSDavid Chisnall __fgetwc(FILE *fp, locale_t locale)
730b7bc802STim J. Robbins {
7424990dfaSTim J. Robbins 	wchar_t wc;
75d6ed810aSTim J. Robbins 	size_t nconv;
76*3c87aa1dSDavid Chisnall 	struct xlocale_ctype *l = XLOCALE_CTYPE(locale);
77e74101e4STim J. Robbins 
78d6ed810aSTim J. Robbins 	if (fp->_r <= 0 && __srefill(fp))
7924990dfaSTim J. Robbins 		return (WEOF);
80fcc51917STim J. Robbins 	if (MB_CUR_MAX == 1) {
81fcc51917STim J. Robbins 		/* Fast path for single-byte encodings. */
82fcc51917STim J. Robbins 		wc = *fp->_p++;
83fcc51917STim J. Robbins 		fp->_r--;
84fcc51917STim J. Robbins 		return (wc);
85fcc51917STim J. Robbins 	}
86d6ed810aSTim J. Robbins 	do {
87*3c87aa1dSDavid Chisnall 		nconv = l->__mbrtowc(&wc, fp->_p, fp->_r, &fp->_mbstate);
88d6ed810aSTim J. Robbins 		if (nconv == (size_t)-1)
8924990dfaSTim J. Robbins 			break;
90d6ed810aSTim J. Robbins 		else if (nconv == (size_t)-2)
9187275e43STim J. Robbins 			continue;
92d6ed810aSTim J. Robbins 		else if (nconv == 0) {
93d6ed810aSTim J. Robbins 			/*
94d6ed810aSTim J. Robbins 			 * Assume that the only valid representation of
95d6ed810aSTim J. Robbins 			 * the null wide character is a single null byte.
96d6ed810aSTim J. Robbins 			 */
97d6ed810aSTim J. Robbins 			fp->_p++;
98d6ed810aSTim J. Robbins 			fp->_r--;
9987275e43STim J. Robbins 			return (L'\0');
100d6ed810aSTim J. Robbins 		} else {
101d6ed810aSTim J. Robbins 			fp->_p += nconv;
102d6ed810aSTim J. Robbins 			fp->_r -= nconv;
10387275e43STim J. Robbins 			return (wc);
10424990dfaSTim J. Robbins 		}
105d6ed810aSTim J. Robbins 	} while (__srefill(fp) == 0);
1066180233fSTim J. Robbins 	fp->_flags |= __SERR;
10787275e43STim J. Robbins 	errno = EILSEQ;
10824990dfaSTim J. Robbins 	return (WEOF);
109e74101e4STim J. Robbins }
110