stdio/FreeBSD/fgetws.c

   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: src/lib/libc/stdio/fgetws.c,v 1.4 2002/09/20 13:25:40 tjr Exp $");
  29
  30 #include "namespace.h"
  31 #include <errno.h>
  32 #include <stdio.h>
  33 #include <wchar.h>
  34 #include "un-namespace.h"
  35 #include "libc_private.h"
  36 #include "local.h"
  37
  38 wchar_t *
  39 fgetws(wchar_t * __restrict ws, int n, FILE * __restrict fp)
  40 {
  41         wchar_t *wsp;
  42         wint_t wc;
  43
  44         FLOCKFILE(fp);
  45         ORIENT(fp, 1);
  46
  47         if (n <= 0) {
  48                 errno = EINVAL;
  49                 goto error;
  50         }
  51
  52         wsp = ws;
  53         while (n-- > 1) {
  54                 /* XXX Inefficient */
  55                 if ((wc = __fgetwc(fp)) == WEOF && errno == EILSEQ)
  56                         goto error;
  57                 if (wc == WEOF) {
  58                         if (wsp == ws)
  59                                 /* EOF/error, no characters read yet. */
  60                                 goto error;
  61                         break;
  62                 }
  63                 *wsp++ = (wchar_t)wc;
  64                 if (wc == L'\n')
  65                         break;
  66         }
  67         *wsp++ = L'\0';
  68         FUNLOCKFILE(fp);
  69
  70         return (ws);
  71
  72 error:
  73         FUNLOCKFILE(fp);
  74         return (NULL);
  75 }