summaryrefslogtreecommitdiffstats
path: root/freebsd/contrib/libpcap/fmtutils.c
blob: ae550e24281d56248a929d098a11fc30f22db33a (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
#include <machine/rtems-bsd-user-space.h>

/*
 * Copyright (c) 1993, 1994, 1995, 1996, 1997, 1998
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the Computer Systems
 *	Engineering Group at Lawrence Berkeley Laboratory.
 * 4. Neither the name of the University nor of the Laboratory may be used
 *    to endorse or promote products derived from this software without
 *    specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

/*
 * Utilities for message formatting used both by libpcap and rpcapd.
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include "ftmacros.h"

#include <stddef.h>
#include <stdarg.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>

#include <pcap/pcap.h>

#include "portability.h"

#include "fmtutils.h"

/*
 * Generate an error message based on a format, arguments, and an
 * errno, with a message for the errno after the formatted output.
 */
void
pcap_fmt_errmsg_for_errno(char *errbuf, size_t errbuflen, int errnum,
    const char *fmt, ...)
{
	va_list ap;
	size_t msglen;
	char *p;
	size_t errbuflen_remaining;
#if defined(HAVE_STRERROR_S)
	errno_t err;
#elif defined(HAVE_STRERROR_R)
	int err;
#endif

	va_start(ap, fmt);
	pcap_vsnprintf(errbuf, errbuflen, fmt, ap);
	va_end(ap);
	msglen = strlen(errbuf);

	/*
	 * Do we have enough space to append ": "?
	 * Including the terminating '\0', that's 3 bytes.
	 */
	if (msglen + 3 > errbuflen) {
		/* No - just give them what we've produced. */
		return;
	}
	p = errbuf + msglen;
	errbuflen_remaining = errbuflen - msglen;
	*p++ = ':';
	*p++ = ' ';
	*p = '\0';
	msglen += 2;
	errbuflen_remaining -= 2;

	/*
	 * Now append the string for the error code.
	 */
#if defined(HAVE_STRERROR_S)
	err = strerror_s(p, errbuflen_remaining, errnum);
	if (err != 0) {
		/*
		 * It doesn't appear to be documented anywhere obvious
		 * what the error returns from strerror_s().
		 */
		pcap_snprintf(p, errbuflen_remaining, "Error %d", errnum);
	}
#elif defined(HAVE_STRERROR_R)
	err = strerror_r(errnum, p, errbuflen_remaining);
	if (err == EINVAL) {
		/*
		 * UNIX 03 says this isn't guaranteed to produce a
		 * fallback error message.
		 */
		pcap_snprintf(p, errbuflen_remaining, "Unknown error: %d",
		    errnum);
	} else if (err == ERANGE) {
		/*
		 * UNIX 03 says this isn't guaranteed to produce a
		 * fallback error message.
		 */
		pcap_snprintf(p, errbuflen_remaining,
		    "Message for error %d is too long", errnum);
	}
#else
	/*
	 * We have neither strerror_s() nor strerror_r(), so we're
	 * stuck with using pcap_strerror().
	 */
	pcap_snprintf(p, errbuflen_remaining, "%s", pcap_strerror(errnum));
#endif
}