1 /* $OpenBSD: fgetwln.c,v 1.4 2016/08/27 12:08:38 schwarze Exp $ */ 2 3 /*- 4 * Copyright (c) 2002-2004 Tim J. Robbins. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <stdio.h> 30 #include <stdlib.h> 31 #include <wchar.h> 32 #include "local.h" 33 34 /* 35 * Expand the line buffer. Return -1 on error. 36 */ 37 static int 38 __slbexpand(FILE *fp, size_t newsize) 39 { 40 void *p; 41 42 if (fp->_lb._size / sizeof(wchar_t) >= newsize) 43 return 0; 44 if ((p = reallocarray(fp->_lb._base, newsize, sizeof(wchar_t))) == NULL) 45 return -1; 46 fp->_lb._base = p; 47 fp->_lb._size = newsize * sizeof(wchar_t); 48 return 0; 49 } 50 51 wchar_t * 52 fgetwln(FILE * __restrict fp, size_t *lenp) 53 { 54 wint_t wc; 55 size_t len; 56 57 FLOCKFILE(fp); 58 _SET_ORIENTATION(fp, 1); 59 60 len = 0; 61 while ((wc = __fgetwc_unlock(fp)) != WEOF) { 62 #define GROW 512 63 if (len >= fp->_lb._size / sizeof(wchar_t) && 64 __slbexpand(fp, len + GROW)) { 65 fp->_flags |= __SERR; 66 goto error; 67 } 68 *((wchar_t *)fp->_lb._base + len++) = wc; 69 if (wc == L'\n') 70 break; 71 } 72 73 /* 74 * The following test assumes that fgetwc() fails when 75 * feof() is already set, and that fgetwc() will never 76 * set feof() in the same call where it also sets ferror() 77 * or returns non-WEOF. 78 * Testing ferror() would not be better because fgetwc() 79 * may succeed even when ferror() is already set. 80 */ 81 82 if (len == 0 || (wc == WEOF && !__sfeof(fp))) 83 goto error; 84 85 FUNLOCKFILE(fp); 86 *lenp = len; 87 return (wchar_t *)fp->_lb._base; 88 89 error: 90 FUNLOCKFILE(fp); 91 *lenp = 0; 92 return NULL; 93 } 94