1/* $NetBSD: getdelim.c,v 1.13 2011/07/22 23:12:30 joerg Exp $ */ 2 3/* 4 * Copyright (c) 2009 The NetBSD Foundation, Inc. 5 * 6 * This code is derived from software contributed to The NetBSD Foundation 7 * by Roy Marples. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 */ 29 30#include <sys/cdefs.h> 31__RCSID("$NetBSD: getdelim.c,v 1.13 2011/07/22 23:12:30 joerg Exp $"); 32 33#include "namespace.h" 34 35#include <sys/param.h> 36 37#include <assert.h> 38#include <errno.h> 39#include <limits.h> 40#include <stdio.h> 41#include <stdlib.h> 42#include <string.h> 43 44#include "reentrant.h" 45#include "local.h" 46 47#ifdef __weak_alias 48__weak_alias(getdelim, _getdelim) 49#endif 50 51/* Minimum buffer size we create. 52 * This should allow config files to fit into our power of 2 buffer growth 53 * without the need for a realloc. */ 54#define MINBUF 128 55 56ssize_t 57__getdelim(char **__restrict buf, size_t *__restrict buflen, 58 int sep, FILE *__restrict fp) 59{ 60 unsigned char *p; 61 size_t len, newlen, off; 62 char *newb; 63 64 _DIAGASSERT(fp != NULL); 65 66 if (buf == NULL || buflen == NULL) { 67 errno = EINVAL; 68 goto error; 69 } 70 71 /* If buf is NULL, we have to assume a size of zero */ 72 if (*buf == NULL) 73 *buflen = 0; 74 75 _SET_ORIENTATION(fp, -1); 76 off = 0; 77 do { 78 /* If the input buffer is empty, refill it */ 79 if (fp->_r <= 0 && __srefill(fp)) { 80 if (__sferror(fp)) 81 goto error; 82 /* No error, so EOF. */ 83 break; 84 } 85 86 /* Scan through looking for the separator */ 87 p = memchr(fp->_p, sep, (size_t)fp->_r); 88 if (p == NULL) 89 len = fp->_r; 90 else 91 len = (p - fp->_p) + 1; 92 93 newlen = off + len; 94 /* Ensure we can handle it */ 95 if (newlen < off || newlen > SSIZE_MAX) { 96 errno = EOVERFLOW; 97 goto error; 98 } 99 newlen++; /* reserve space for the NULL terminator */ 100 if (newlen > *buflen) { 101 if (newlen < MINBUF) 102 newlen = MINBUF; 103 if (!powerof2(newlen)) { 104 /* Grow the buffer to the next power of 2 */ 105 newlen--; 106 newlen |= newlen >> 1; 107 newlen |= newlen >> 2; 108 newlen |= newlen >> 4; 109 newlen |= newlen >> 8; 110 newlen |= newlen >> 16; 111#if SIZE_T_MAX > 0xffffffffU 112 newlen |= newlen >> 32; 113#endif 114 newlen++; 115 } 116 117 newb = realloc(*buf, newlen); 118 if (newb == NULL) 119 goto error; 120 *buf = newb; 121 *buflen = newlen; 122 } 123 124 (void)memcpy((*buf + off), fp->_p, len); 125 /* Safe, len is never greater than what fp->_r can fit. */ 126 fp->_r -= (int)len; 127 fp->_p += (int)len; 128 off += len; 129 } while (p == NULL); 130 131 /* POSIX demands we return -1 on EOF. */ 132 if (off == 0) 133 return -1; 134 135 if (*buf != NULL) 136 *(*buf + off) = '\0'; 137 return off; 138 139error: 140 fp->_flags |= __SERR; 141 return -1; 142} 143 144ssize_t 145getdelim(char **__restrict buf, size_t *__restrict buflen, 146 int sep, FILE *__restrict fp) 147{ 148 ssize_t n; 149 150 FLOCKFILE(fp); 151 n = __getdelim(buf, buflen, sep, fp); 152 FUNLOCKFILE(fp); 153 return n; 154} 155