xref: /netbsd-src/lib/libc/stdio/vdprintf.c (revision 93b012cb25794577ed8e68ee2350c1273c7ba68f)
1 /*	$NetBSD: vdprintf.c,v 1.6 2020/08/28 22:02:24 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 1.6 2020/08/28 22:02:24 christos Exp $");
38 #endif /* LIBC_SCCS and not lint */
39 
40 #include "namespace.h"
41 #include <sys/types.h>
42 
43 #include <assert.h>
44 #include <errno.h>
45 #include <fcntl.h>
46 #include <locale.h>
47 #include <unistd.h>
48 #include <stdio.h>
49 #include <limits.h>
50 
51 #include "reentrant.h"
52 #include "setlocale_local.h"
53 #include "local.h"
54 
55 #ifdef __weak_alias
__weak_alias(vdprintf,_vdprintf)56 __weak_alias(vdprintf,_vdprintf)
57 __weak_alias(vdprintf_l,_vdprintf_l)
58 #endif
59 
60 int
61 vdprintf_l(int fd, locale_t loc, const char * __restrict fmt, va_list ap)
62 {
63 	FILE f;
64 	struct __sfileext fext;
65 	unsigned char buf[BUFSIZ];
66 	int ret, fdflags, tmp;
67 
68 	_DIAGASSERT(fd != -1);
69 
70 	/*
71 	 * File descriptors are a full int, but _file is only a short.
72 	 * If we get a valid file descriptor that is greater or equal to
73 	 * USHRT_MAX, then the fd will get sign-extended into an
74 	 * invalid file descriptor.  Handle this case by failing the
75 	 * open. (We treat the short as unsigned, and special-case -1).
76 	 */
77 	if (fd >= USHRT_MAX) {
78 		errno = EMFILE;
79 		return EOF;
80 	}
81 
82 	if ((fdflags = fcntl(fd, F_GETFL, 0)) == -1)
83 		return EOF;
84 
85 	tmp = fdflags & O_ACCMODE;
86 	if (tmp != O_RDWR && tmp != O_WRONLY) {
87 		errno = EINVAL;
88 		return EOF;
89 	}
90 
91 	_FILEEXT_SETUP(&f, &fext);
92 	__sfpinit(&f);
93 	f._p = buf;
94 	f._w = sizeof(buf);
95 	f._flags = __SWR;
96 	f._file = fd;
97 	f._bf._base = buf;
98 	f._bf._size = sizeof(buf);
99 	f._cookie = &f;
100 	f._read = NULL;
101 	f._write = __swrite;
102 	f._seek = NULL;
103 	f._close = NULL;
104 
105 	if ((ret = vfprintf_l(&f, loc, fmt, ap)) < 0)
106 		return ret;
107 
108 	return fflush(&f) ? EOF : ret;
109 }
110 
111 int
vdprintf(int fd,const char * __restrict fmt,va_list ap)112 vdprintf(int fd, const char * __restrict fmt, va_list ap)
113 {
114 	return vdprintf_l(fd, _current_locale(), fmt, ap);
115 }
116