lib/libc/stdio/fgetws.c

   1 /*-
   2  * Copyright (c) 2002-2004 Tim J. Robbins.
   3  * All rights reserved.
   4  *
   5  * Copyright (c) 2011 The FreeBSD Foundation
   6  * All rights reserved.
   7  * Portions of this software were developed by David Chisnall
   8  * under sponsorship from the FreeBSD Foundation.
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  * 1. Redistributions of source code must retain the above copyright
  14  *    notice, this list of conditions and the following disclaimer.
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  29  * SUCH DAMAGE.
  30  *
  31  * $FreeBSD: head/lib/libc/stdio/fgetws.c 227753 2011-11-20 14:45:42Z theraven $
  32  */
  33
  34
  35 #include "namespace.h"
  36 #include <errno.h>
  37 #include <stdio.h>
  38 #include <string.h>
  39 #include <wchar.h>
  40 #include "un-namespace.h"
  41 #include "libc_private.h"
  42 #include "local.h"
  43 #include "mblocal.h"
  44
  45 wchar_t *
  46 fgetws_l(wchar_t * __restrict ws, int n, FILE * __restrict fp, locale_t locale)
  47 {
  48         struct wchar_io_data *wcio;
  49         mbstate_t *st;
  50         wchar_t *wsp;
  51         size_t nconv;
  52         const char *src;
  53         unsigned char *nl;
  54         FIX_LOCALE(locale);
  55         struct xlocale_ctype *l = XLOCALE_CTYPE(locale);
  56
  57         FLOCKFILE(fp);
  58         ORIENT(fp, 1);
  59         wcio = WCIO_GET(fp);
  60         if (wcio == NULL) {
  61                 errno = ENOMEM;
  62                 goto error;
  63         }
  64
  65         if (n <= 0) {
  66                 errno = EINVAL;
  67                 goto error;
  68         }
  69
  70         wcio->wcio_ungetwc_inbuf = 0;
  71         st = &wcio->wcio_mbstate_out;
  72
  73         if (fp->pub._r <= 0 && __srefill(fp))
  74                 /* EOF */
  75                 goto error;
  76         wsp = ws;
  77         do {
  78                 src = fp->pub._p;
  79                 nl = memchr(fp->pub._p, '\n', fp->pub._r);
  80                 nconv = l->__mbsnrtowcs(wsp, &src,
  81                     nl != NULL ? (nl - fp->pub._p + 1) :
  82                     fp->pub._r, n - 1, st);
  83                 if (nconv == (size_t)-1)
  84                         /* Conversion error */
  85                         goto error;
  86                 if (src == NULL) {
  87                         /*
  88                          * We hit a null byte. Increment the character count,
  89                          * since mbsnrtowcs()'s return value doesn't include
  90                          * the terminating null, then resume conversion
  91                          * after the null.
  92                          */
  93                         nconv++;
  94                         src = memchr(fp->pub._p, '\0', fp->pub._r);
  95                         src++;
  96                 }
  97                 fp->pub._r -= (unsigned char *)src - fp->pub._p;
  98                 fp->pub._p = (unsigned char *)src;
  99                 n -= nconv;
 100                 wsp += nconv;
 101         } while (wsp[-1] != L'\n' && n > 1 && (fp->pub._r > 0 ||
 102             __srefill(fp) == 0));
 103         if (wsp == ws)
 104                 /* EOF */
 105                 goto error;
 106         if (!l->__mbsinit(st))
 107                 /* Incomplete character */
 108                 goto error;
 109         *wsp = L'\0';
 110         FUNLOCKFILE(fp);
 111
 112         return (ws);
 113
 114 error:
 115         FUNLOCKFILE(fp);
 116         return (NULL);
 117 }
 118 wchar_t *
 119 fgetws(wchar_t * __restrict ws, int n, FILE * __restrict fp)
 120 {
 121         return fgetws_l(ws, n, fp, __get_locale());
 122 }