| 1 | /*-␊ |
| 2 | * Copyright (c) 1990, 1993␊ |
| 3 | *␉The Regents of the University of California. All rights reserved.␊ |
| 4 | *␊ |
| 5 | * This code is derived from software contributed to Berkeley by␊ |
| 6 | * Chris Torek.␊ |
| 7 | *␊ |
| 8 | * Redistribution and use in source and binary forms, with or without␊ |
| 9 | * modification, are permitted provided that the following conditions␊ |
| 10 | * are met:␊ |
| 11 | * 1. Redistributions of source code must retain the above copyright␊ |
| 12 | * notice, this list of conditions and the following disclaimer.␊ |
| 13 | * 2. Redistributions in binary form must reproduce the above copyright␊ |
| 14 | * notice, this list of conditions and the following disclaimer in the␊ |
| 15 | * documentation and/or other materials provided with the distribution.␊ |
| 16 | * 4. Neither the name of the University nor the names of its contributors␊ |
| 17 | * may be used to endorse or promote products derived from this software␊ |
| 18 | * without specific prior written permission.␊ |
| 19 | *␊ |
| 20 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND␊ |
| 21 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE␊ |
| 22 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE␊ |
| 23 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE␊ |
| 24 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL␊ |
| 25 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS␊ |
| 26 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)␊ |
| 27 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT␊ |
| 28 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY␊ |
| 29 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF␊ |
| 30 | * SUCH DAMAGE.␊ |
| 31 | */␊ |
| 32 | ␊ |
| 33 | #if defined(LIBC_SCCS) && !defined(lint)␊ |
| 34 | static char sccsid[] = "@(#)fvwrite.c␉8.1 (Berkeley) 6/4/93";␊ |
| 35 | #endif /* LIBC_SCCS and not lint */␊ |
| 36 | #include <sys/cdefs.h>␊ |
| 37 | //__FBSDID("$FreeBSD: src/lib/libc/stdio/fvwrite.c,v 1.19 2009/11/25 04:21:42 wollman Exp $");␊ |
| 38 | ␊ |
| 39 | #include "stdio.h"␊ |
| 40 | #include "errno.h"␊ |
| 41 | #include "local.h"␊ |
| 42 | #include "fvwrite.h"␊ |
| 43 | ␊ |
| 44 | /*␊ |
| 45 | * Write some memory regions. Return zero on success, EOF on error.␊ |
| 46 | *␊ |
| 47 | * This routine is large and unsightly, but most of the ugliness due␊ |
| 48 | * to the three different kinds of output buffering is handled here.␊ |
| 49 | */␊ |
| 50 | int␊ |
| 51 | __sfvwrite(fp, uio)␊ |
| 52 | ␉FILE *fp;␊ |
| 53 | ␉struct __suio *uio;␊ |
| 54 | {␊ |
| 55 | ␉size_t len;␊ |
| 56 | ␉char *p;␊ |
| 57 | ␉struct __siov *iov;␊ |
| 58 | ␉int w, s;␊ |
| 59 | ␉char *nl;␊ |
| 60 | ␉int nlknown, nldist;␊ |
| 61 | ␊ |
| 62 | ␉if (uio->uio_resid == 0)␊ |
| 63 | ␉␉return (0);␊ |
| 64 | ␉/* make sure we can write */␊ |
| 65 | ␉if (prepwrite(fp) != 0)␊ |
| 66 | ␉␉return (EOF);␊ |
| 67 | ␊ |
| 68 | #define␉MIN(a, b) ((a) < (b) ? (a) : (b))␊ |
| 69 | #define␉COPY(n)␉ (void)memcpy((void *)fp->_p, (void *)p, (size_t)(n))␊ |
| 70 | ␊ |
| 71 | ␉iov = uio->uio_iov;␊ |
| 72 | ␉p = iov->iov_base;␊ |
| 73 | ␉len = iov->iov_len;␊ |
| 74 | ␉iov++;␊ |
| 75 | #define GETIOV(extra_work) \␊ |
| 76 | ␉while (len == 0) { \␊ |
| 77 | ␉␉extra_work; \␊ |
| 78 | ␉␉p = iov->iov_base; \␊ |
| 79 | ␉␉len = iov->iov_len; \␊ |
| 80 | ␉␉iov++; \␊ |
| 81 | ␉}␊ |
| 82 | ␉if (fp->_flags & __SNBF) {␊ |
| 83 | ␉␉/*␊ |
| 84 | ␉␉ * Unbuffered: write up to BUFSIZ bytes at a time.␊ |
| 85 | ␉␉ */␊ |
| 86 | ␉␉do {␊ |
| 87 | ␉␉␉GETIOV(;);␊ |
| 88 | ␉␉␉w = _swrite(fp, p, MIN(len, BUFSIZ));␊ |
| 89 | ␉␉␉if (w <= 0)␊ |
| 90 | ␉␉␉␉goto err;␊ |
| 91 | ␉␉␉p += w;␊ |
| 92 | ␉␉␉len -= w;␊ |
| 93 | ␉␉} while ((uio->uio_resid -= w) != 0);␊ |
| 94 | ␉} else if ((fp->_flags & __SLBF) == 0) {␊ |
| 95 | ␉␉/*␊ |
| 96 | ␉␉ * Fully buffered: fill partially full buffer, if any,␊ |
| 97 | ␉␉ * and then flush. If there is no partial buffer, write␊ |
| 98 | ␉␉ * one _bf._size byte chunk directly (without copying).␊ |
| 99 | ␉␉ *␊ |
| 100 | ␉␉ * String output is a special case: write as many bytes␊ |
| 101 | ␉␉ * as fit, but pretend we wrote everything. This makes␊ |
| 102 | ␉␉ * snprintf() return the number of bytes needed, rather␊ |
| 103 | ␉␉ * than the number used, and avoids its write function␊ |
| 104 | ␉␉ * (so that the write function can be invalid).␊ |
| 105 | ␉␉ */␊ |
| 106 | ␉␉do {␊ |
| 107 | ␉␉␉GETIOV(;);␊ |
| 108 | ␉␉␉if ((fp->_flags & (__SALC | __SSTR)) ==␊ |
| 109 | ␉␉␉ (__SALC | __SSTR) && fp->_w < len) {␊ |
| 110 | ␉␉␉␉size_t blen = fp->_p - fp->_bf._base;␊ |
| 111 | ␊ |
| 112 | ␉␉␉␉/*␊ |
| 113 | ␉␉␉␉ * Alloc an extra 128 bytes (+ 1 for NULL)␊ |
| 114 | ␉␉␉␉ * so we don't call realloc(3) so often.␊ |
| 115 | ␉␉␉␉ */␊ |
| 116 | ␉␉␉␉fp->_w = len + 128;␊ |
| 117 | ␉␉␉␉fp->_bf._size = blen + len + 128;␊ |
| 118 | ␉␉␉␉fp->_bf._base =␊ |
| 119 | ␉␉␉␉ reallocf(fp->_bf._base, fp->_bf._size + 1);␊ |
| 120 | ␉␉␉␉if (fp->_bf._base == NULL)␊ |
| 121 | ␉␉␉␉␉goto err;␊ |
| 122 | ␉␉␉␉fp->_p = fp->_bf._base + blen;␊ |
| 123 | ␉␉␉}␊ |
| 124 | ␉␉␉w = fp->_w;␊ |
| 125 | ␉␉␉if (fp->_flags & __SSTR) {␊ |
| 126 | ␉␉␉␉if (len < w)␊ |
| 127 | ␉␉␉␉␉w = len;␊ |
| 128 | ␉␉␉␉if (w > 0) {␊ |
| 129 | ␉␉␉␉␉COPY(w); /* copy MIN(fp->_w,len), */␊ |
| 130 | ␉␉␉␉␉fp->_w -= w;␊ |
| 131 | ␉␉␉␉␉fp->_p += w;␊ |
| 132 | ␉␉␉␉}␊ |
| 133 | ␉␉␉␉w = len;␉/* but pretend copied all */␊ |
| 134 | ␉␉␉} else if (fp->_p > fp->_bf._base && len > w) {␊ |
| 135 | ␉␉␉␉/* fill and flush */␊ |
| 136 | ␉␉␉␉COPY(w);␊ |
| 137 | ␉␉␉␉/* fp->_w -= w; */ /* unneeded */␊ |
| 138 | ␉␉␉␉fp->_p += w;␊ |
| 139 | ␉␉␉␉if (__fflush(fp))␊ |
| 140 | ␉␉␉␉␉goto err;␊ |
| 141 | ␉␉␉} else if (len >= (w = fp->_bf._size)) {␊ |
| 142 | ␉␉␉␉/* write directly */␊ |
| 143 | ␉␉␉␉w = _swrite(fp, p, w);␊ |
| 144 | ␉␉␉␉if (w <= 0)␊ |
| 145 | ␉␉␉␉␉goto err;␊ |
| 146 | ␉␉␉} else {␊ |
| 147 | ␉␉␉␉/* fill and done */␊ |
| 148 | ␉␉␉␉w = len;␊ |
| 149 | ␉␉␉␉COPY(w);␊ |
| 150 | ␉␉␉␉fp->_w -= w;␊ |
| 151 | ␉␉␉␉fp->_p += w;␊ |
| 152 | ␉␉␉}␊ |
| 153 | ␉␉␉p += w;␊ |
| 154 | ␉␉␉len -= w;␊ |
| 155 | ␉␉} while ((uio->uio_resid -= w) != 0);␊ |
| 156 | ␉} else {␊ |
| 157 | ␉␉/*␊ |
| 158 | ␉␉ * Line buffered: like fully buffered, but we␊ |
| 159 | ␉␉ * must check for newlines. Compute the distance␊ |
| 160 | ␉␉ * to the first newline (including the newline),␊ |
| 161 | ␉␉ * or `infinity' if there is none, then pretend␊ |
| 162 | ␉␉ * that the amount to write is MIN(len,nldist).␊ |
| 163 | ␉␉ */␊ |
| 164 | ␉␉nlknown = 0;␊ |
| 165 | ␉␉nldist = 0;␉/* XXX just to keep gcc happy */␊ |
| 166 | ␉␉do {␊ |
| 167 | ␉␉␉GETIOV(nlknown = 0);␊ |
| 168 | ␉␉␉if (!nlknown) {␊ |
| 169 | ␉␉␉␉nl = memchr((void *)p, '\n', len);␊ |
| 170 | ␉␉␉␉nldist = nl ? nl + 1 - p : len + 1;␊ |
| 171 | ␉␉␉␉nlknown = 1;␊ |
| 172 | ␉␉␉}␊ |
| 173 | ␉␉␉s = MIN(len, nldist);␊ |
| 174 | ␉␉␉w = fp->_w + fp->_bf._size;␊ |
| 175 | ␉␉␉if (fp->_p > fp->_bf._base && s > w) {␊ |
| 176 | ␉␉␉␉COPY(w);␊ |
| 177 | ␉␉␉␉/* fp->_w -= w; */␊ |
| 178 | ␉␉␉␉fp->_p += w;␊ |
| 179 | ␉␉␉␉if (__fflush(fp))␊ |
| 180 | ␉␉␉␉␉goto err;␊ |
| 181 | ␉␉␉} else if (s >= (w = fp->_bf._size)) {␊ |
| 182 | ␉␉␉␉w = _swrite(fp, p, w);␊ |
| 183 | ␉␉␉␉if (w <= 0)␊ |
| 184 | ␉␉␉␉ ␉goto err;␊ |
| 185 | ␉␉␉} else {␊ |
| 186 | ␉␉␉␉w = s;␊ |
| 187 | ␉␉␉␉COPY(w);␊ |
| 188 | ␉␉␉␉fp->_w -= w;␊ |
| 189 | ␉␉␉␉fp->_p += w;␊ |
| 190 | ␉␉␉}␊ |
| 191 | ␉␉␉if ((nldist -= w) == 0) {␊ |
| 192 | ␉␉␉␉/* copied the newline: flush and forget */␊ |
| 193 | ␉␉␉␉if (__fflush(fp))␊ |
| 194 | ␉␉␉␉␉goto err;␊ |
| 195 | ␉␉␉␉nlknown = 0;␊ |
| 196 | ␉␉␉}␊ |
| 197 | ␉␉␉p += w;␊ |
| 198 | ␉␉␉len -= w;␊ |
| 199 | ␉␉} while ((uio->uio_resid -= w) != 0);␊ |
| 200 | ␉}␊ |
| 201 | ␉return (0);␊ |
| 202 | ␊ |
| 203 | err:␊ |
| 204 | ␉fp->_flags |= __SERR;␊ |
| 205 | ␉return (EOF);␊ |
| 206 | }␊ |
| 207 | |
