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 <stdlib.h>␊ |
41 | #include <string.h>␊ |
42 | #include "local.h"␊ |
43 | #include "fvwrite.h"␊ |
44 | ␊ |
45 | /*␊ |
46 | * Write some memory regions. Return zero on success, EOF on error.␊ |
47 | *␊ |
48 | * This routine is large and unsightly, but most of the ugliness due␊ |
49 | * to the three different kinds of output buffering is handled here.␊ |
50 | */␊ |
51 | int␊ |
52 | __sfvwrite(fp, uio)␊ |
53 | ␉FILE *fp;␊ |
54 | ␉struct __suio *uio;␊ |
55 | {␊ |
56 | ␉size_t len;␊ |
57 | ␉char *p;␊ |
58 | ␉struct __siov *iov;␊ |
59 | ␉int w, s;␊ |
60 | ␉char *nl;␊ |
61 | ␉int nlknown, nldist;␊ |
62 | ␊ |
63 | ␉if (uio->uio_resid == 0)␊ |
64 | ␉␉return (0);␊ |
65 | ␉/* make sure we can write */␊ |
66 | ␉if (prepwrite(fp) != 0)␊ |
67 | ␉␉return (EOF);␊ |
68 | ␊ |
69 | #define␉MIN(a, b) ((a) < (b) ? (a) : (b))␊ |
70 | #define␉COPY(n)␉ (void)memcpy((void *)fp->_p, (void *)p, (size_t)(n))␊ |
71 | ␊ |
72 | ␉iov = uio->uio_iov;␊ |
73 | ␉p = iov->iov_base;␊ |
74 | ␉len = iov->iov_len;␊ |
75 | ␉iov++;␊ |
76 | #define GETIOV(extra_work) \␊ |
77 | ␉while (len == 0) { \␊ |
78 | ␉␉extra_work; \␊ |
79 | ␉␉p = iov->iov_base; \␊ |
80 | ␉␉len = iov->iov_len; \␊ |
81 | ␉␉iov++; \␊ |
82 | ␉}␊ |
83 | ␉if (fp->_flags & __SNBF) {␊ |
84 | ␉␉/*␊ |
85 | ␉␉ * Unbuffered: write up to BUFSIZ bytes at a time.␊ |
86 | ␉␉ */␊ |
87 | ␉␉do {␊ |
88 | ␉␉␉GETIOV(;);␊ |
89 | ␉␉␉w = _swrite(fp, p, MIN(len, BUFSIZ));␊ |
90 | ␉␉␉if (w <= 0)␊ |
91 | ␉␉␉␉goto err;␊ |
92 | ␉␉␉p += w;␊ |
93 | ␉␉␉len -= w;␊ |
94 | ␉␉} while ((uio->uio_resid -= w) != 0);␊ |
95 | ␉} else if ((fp->_flags & __SLBF) == 0) {␊ |
96 | ␉␉/*␊ |
97 | ␉␉ * Fully buffered: fill partially full buffer, if any,␊ |
98 | ␉␉ * and then flush. If there is no partial buffer, write␊ |
99 | ␉␉ * one _bf._size byte chunk directly (without copying).␊ |
100 | ␉␉ *␊ |
101 | ␉␉ * String output is a special case: write as many bytes␊ |
102 | ␉␉ * as fit, but pretend we wrote everything. This makes␊ |
103 | ␉␉ * snprintf() return the number of bytes needed, rather␊ |
104 | ␉␉ * than the number used, and avoids its write function␊ |
105 | ␉␉ * (so that the write function can be invalid).␊ |
106 | ␉␉ */␊ |
107 | ␉␉do {␊ |
108 | ␉␉␉GETIOV(;);␊ |
109 | ␉␉␉if ((fp->_flags & (__SALC | __SSTR)) ==␊ |
110 | ␉␉␉ (__SALC | __SSTR) && fp->_w < len) {␊ |
111 | ␉␉␉␉size_t blen = fp->_p - fp->_bf._base;␊ |
112 | ␊ |
113 | ␉␉␉␉/*␊ |
114 | ␉␉␉␉ * Alloc an extra 128 bytes (+ 1 for NULL)␊ |
115 | ␉␉␉␉ * so we don't call realloc(3) so often.␊ |
116 | ␉␉␉␉ */␊ |
117 | ␉␉␉␉fp->_w = len + 128;␊ |
118 | ␉␉␉␉fp->_bf._size = blen + len + 128;␊ |
119 | ␉␉␉␉fp->_bf._base =␊ |
120 | ␉␉␉␉ reallocf(fp->_bf._base, fp->_bf._size + 1);␊ |
121 | ␉␉␉␉if (fp->_bf._base == NULL)␊ |
122 | ␉␉␉␉␉goto err;␊ |
123 | ␉␉␉␉fp->_p = fp->_bf._base + blen;␊ |
124 | ␉␉␉}␊ |
125 | ␉␉␉w = fp->_w;␊ |
126 | ␉␉␉if (fp->_flags & __SSTR) {␊ |
127 | ␉␉␉␉if (len < w)␊ |
128 | ␉␉␉␉␉w = len;␊ |
129 | ␉␉␉␉if (w > 0) {␊ |
130 | ␉␉␉␉␉COPY(w); /* copy MIN(fp->_w,len), */␊ |
131 | ␉␉␉␉␉fp->_w -= w;␊ |
132 | ␉␉␉␉␉fp->_p += w;␊ |
133 | ␉␉␉␉}␊ |
134 | ␉␉␉␉w = len;␉/* but pretend copied all */␊ |
135 | ␉␉␉} else if (fp->_p > fp->_bf._base && len > w) {␊ |
136 | ␉␉␉␉/* fill and flush */␊ |
137 | ␉␉␉␉COPY(w);␊ |
138 | ␉␉␉␉/* fp->_w -= w; */ /* unneeded */␊ |
139 | ␉␉␉␉fp->_p += w;␊ |
140 | ␉␉␉␉if (__fflush(fp))␊ |
141 | ␉␉␉␉␉goto err;␊ |
142 | ␉␉␉} else if (len >= (w = fp->_bf._size)) {␊ |
143 | ␉␉␉␉/* write directly */␊ |
144 | ␉␉␉␉w = _swrite(fp, p, w);␊ |
145 | ␉␉␉␉if (w <= 0)␊ |
146 | ␉␉␉␉␉goto err;␊ |
147 | ␉␉␉} else {␊ |
148 | ␉␉␉␉/* fill and done */␊ |
149 | ␉␉␉␉w = len;␊ |
150 | ␉␉␉␉COPY(w);␊ |
151 | ␉␉␉␉fp->_w -= w;␊ |
152 | ␉␉␉␉fp->_p += w;␊ |
153 | ␉␉␉}␊ |
154 | ␉␉␉p += w;␊ |
155 | ␉␉␉len -= w;␊ |
156 | ␉␉} while ((uio->uio_resid -= w) != 0);␊ |
157 | ␉} else {␊ |
158 | ␉␉/*␊ |
159 | ␉␉ * Line buffered: like fully buffered, but we␊ |
160 | ␉␉ * must check for newlines. Compute the distance␊ |
161 | ␉␉ * to the first newline (including the newline),␊ |
162 | ␉␉ * or `infinity' if there is none, then pretend␊ |
163 | ␉␉ * that the amount to write is MIN(len,nldist).␊ |
164 | ␉␉ */␊ |
165 | ␉␉nlknown = 0;␊ |
166 | ␉␉nldist = 0;␉/* XXX just to keep gcc happy */␊ |
167 | ␉␉do {␊ |
168 | ␉␉␉GETIOV(nlknown = 0);␊ |
169 | ␉␉␉if (!nlknown) {␊ |
170 | ␉␉␉␉nl = memchr((void *)p, '\n', len);␊ |
171 | ␉␉␉␉nldist = nl ? nl + 1 - p : len + 1;␊ |
172 | ␉␉␉␉nlknown = 1;␊ |
173 | ␉␉␉}␊ |
174 | ␉␉␉s = MIN(len, nldist);␊ |
175 | ␉␉␉w = fp->_w + fp->_bf._size;␊ |
176 | ␉␉␉if (fp->_p > fp->_bf._base && s > w) {␊ |
177 | ␉␉␉␉COPY(w);␊ |
178 | ␉␉␉␉/* fp->_w -= w; */␊ |
179 | ␉␉␉␉fp->_p += w;␊ |
180 | ␉␉␉␉if (__fflush(fp))␊ |
181 | ␉␉␉␉␉goto err;␊ |
182 | ␉␉␉} else if (s >= (w = fp->_bf._size)) {␊ |
183 | ␉␉␉␉w = _swrite(fp, p, w);␊ |
184 | ␉␉␉␉if (w <= 0)␊ |
185 | ␉␉␉␉ ␉goto err;␊ |
186 | ␉␉␉} else {␊ |
187 | ␉␉␉␉w = s;␊ |
188 | ␉␉␉␉COPY(w);␊ |
189 | ␉␉␉␉fp->_w -= w;␊ |
190 | ␉␉␉␉fp->_p += w;␊ |
191 | ␉␉␉}␊ |
192 | ␉␉␉if ((nldist -= w) == 0) {␊ |
193 | ␉␉␉␉/* copied the newline: flush and forget */␊ |
194 | ␉␉␉␉if (__fflush(fp))␊ |
195 | ␉␉␉␉␉goto err;␊ |
196 | ␉␉␉␉nlknown = 0;␊ |
197 | ␉␉␉}␊ |
198 | ␉␉␉p += w;␊ |
199 | ␉␉␉len -= w;␊ |
200 | ␉␉} while ((uio->uio_resid -= w) != 0);␊ |
201 | ␉}␊ |
202 | ␉return (0);␊ |
203 | ␊ |
204 | err:␊ |
205 | ␉fp->_flags |= __SERR;␊ |
206 | ␉return (EOF);␊ |
207 | }␊ |
208 | |