vdprintf.c revision 1.5 
1/*	$NetBSD: vdprintf.c,v 1.5 2017/01/10 17:45:12 christos Exp $	*/
2
3/*-
4 * Copyright (c) 1990, 1993
5 *	The Regents of the University of California.  All rights reserved.
6 *
7 * This code is derived from software contributed to Berkeley by
8 * Chris Torek.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. Neither the name of the University nor the names of its contributors
19 *    may be used to endorse or promote products derived from this software
20 *    without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35#include <sys/cdefs.h>
36#if defined(LIBC_SCCS) && !defined(lint)
37__RCSID("$NetBSD: vdprintf.c,v 1.5 2017/01/10 17:45:12 christos Exp $");
38#endif /* LIBC_SCCS and not lint */
39
40#include "namespace.h"
41#include <sys/types.h>
42#include <sys/stat.h>
43
44#include <assert.h>
45#include <errno.h>
46#include <fcntl.h>
47#include <locale.h>
48#include <unistd.h>
49#include <stdio.h>
50#include <limits.h>
51
52#include "reentrant.h"
53#include "setlocale_local.h"
54#include "local.h"
55
56#ifdef __weak_alias
57__weak_alias(vdprintf,_vdprintf)
58__weak_alias(vdprintf_l,_vdprintf_l)
59#endif
60
61int
62vdprintf_l(int fd, locale_t loc, const char * __restrict fmt, va_list ap)
63{
64	FILE f;
65	struct __sfileext fext;
66	unsigned char buf[BUFSIZ];
67	int ret, fdflags, tmp;
68
69	_DIAGASSERT(fd != -1);
70
71	/*
72	 * File descriptors are a full int, but _file is only a short.
73	 * If we get a valid file descriptor that is greater or equal to
74	 * USHRT_MAX, then the fd will get sign-extended into an
75	 * invalid file descriptor.  Handle this case by failing the
76	 * open. (We treat the short as unsigned, and special-case -1).
77	 */
78	if (fd >= USHRT_MAX) {
79		errno = EMFILE;
80		return EOF;
81	}
82
83	if ((fdflags = fcntl(fd, F_GETFL, 0)) == -1)
84		return EOF;
85
86	tmp = fdflags & O_ACCMODE;
87	if (tmp != O_RDWR && tmp != O_WRONLY) {
88		errno = EINVAL;
89		return EOF;
90	}
91
92	if (fdflags & O_NONBLOCK) {
93		struct stat st;
94		if (fstat(fd, &st) == -1)
95			return -1;
96		if (!S_ISREG(st.st_mode)) {
97			errno = EFTYPE;
98			return EOF;
99		}
100	}
101
102	_FILEEXT_SETUP(&f, &fext);
103	__sfpinit(&f);
104	f._p = buf;
105	f._w = sizeof(buf);
106	f._flags = __SWR;
107	f._file = fd;
108	f._bf._base = buf;
109	f._bf._size = sizeof(buf);
110	f._cookie = &f;
111	f._read = NULL;
112	f._write = __swrite;
113	f._seek = NULL;
114	f._close = NULL;
115
116	if ((ret = vfprintf_l(&f, loc, fmt, ap)) < 0)
117		return ret;
118
119	return fflush(&f) ? EOF : ret;
120}
121
122int
123vdprintf(int fd, const char * __restrict fmt, va_list ap)
124{
125	return vdprintf_l(fd, _current_locale(), fmt, ap);
126}
127