10036d835Schristos /*
20036d835Schristos * Copyright (c) 1993, 1994, 1995, 1996, 1997, 1998
30036d835Schristos * The Regents of the University of California. All rights reserved.
40036d835Schristos *
50036d835Schristos * Redistribution and use in source and binary forms, with or without
60036d835Schristos * modification, are permitted provided that the following conditions
70036d835Schristos * are met:
80036d835Schristos * 1. Redistributions of source code must retain the above copyright
90036d835Schristos * notice, this list of conditions and the following disclaimer.
100036d835Schristos * 2. Redistributions in binary form must reproduce the above copyright
110036d835Schristos * notice, this list of conditions and the following disclaimer in the
120036d835Schristos * documentation and/or other materials provided with the distribution.
130036d835Schristos * 3. All advertising materials mentioning features or use of this software
140036d835Schristos * must display the following acknowledgement:
150036d835Schristos * This product includes software developed by the Computer Systems
160036d835Schristos * Engineering Group at Lawrence Berkeley Laboratory.
170036d835Schristos * 4. Neither the name of the University nor of the Laboratory may be used
180036d835Schristos * to endorse or promote products derived from this software without
190036d835Schristos * specific prior written permission.
200036d835Schristos *
210036d835Schristos * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
220036d835Schristos * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
230036d835Schristos * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
240036d835Schristos * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
250036d835Schristos * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
260036d835Schristos * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
270036d835Schristos * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
280036d835Schristos * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
290036d835Schristos * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
300036d835Schristos * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
310036d835Schristos * SUCH DAMAGE.
320036d835Schristos */
330036d835Schristos
340036d835Schristos /*
350036d835Schristos * Utilities for message formatting used both by libpcap and rpcapd.
360036d835Schristos */
370036d835Schristos
380036d835Schristos #ifdef HAVE_CONFIG_H
390036d835Schristos #include <config.h>
400036d835Schristos #endif
410036d835Schristos
420036d835Schristos #include "ftmacros.h"
430036d835Schristos
440036d835Schristos #include <stddef.h>
450036d835Schristos #include <stdarg.h>
460036d835Schristos #include <stdio.h>
470036d835Schristos #include <string.h>
480036d835Schristos #include <errno.h>
490036d835Schristos
500036d835Schristos #include <pcap/pcap.h>
510036d835Schristos
520036d835Schristos #include "portability.h"
530036d835Schristos
540036d835Schristos #include "fmtutils.h"
550036d835Schristos
560036d835Schristos /*
570036d835Schristos * Generate an error message based on a format, arguments, and an
580036d835Schristos * errno, with a message for the errno after the formatted output.
590036d835Schristos */
600036d835Schristos void
pcap_fmt_errmsg_for_errno(char * errbuf,size_t errbuflen,int errnum,const char * fmt,...)610036d835Schristos pcap_fmt_errmsg_for_errno(char *errbuf, size_t errbuflen, int errnum,
620036d835Schristos const char *fmt, ...)
630036d835Schristos {
640036d835Schristos va_list ap;
650036d835Schristos size_t msglen;
660036d835Schristos char *p;
670036d835Schristos size_t errbuflen_remaining;
680036d835Schristos
690036d835Schristos va_start(ap, fmt);
700036d835Schristos pcap_vsnprintf(errbuf, errbuflen, fmt, ap);
710036d835Schristos va_end(ap);
720036d835Schristos msglen = strlen(errbuf);
730036d835Schristos
740036d835Schristos /*
750036d835Schristos * Do we have enough space to append ": "?
760036d835Schristos * Including the terminating '\0', that's 3 bytes.
770036d835Schristos */
780036d835Schristos if (msglen + 3 > errbuflen) {
790036d835Schristos /* No - just give them what we've produced. */
800036d835Schristos return;
810036d835Schristos }
820036d835Schristos p = errbuf + msglen;
830036d835Schristos errbuflen_remaining = errbuflen - msglen;
840036d835Schristos *p++ = ':';
850036d835Schristos *p++ = ' ';
860036d835Schristos *p = '\0';
870036d835Schristos msglen += 2;
880036d835Schristos errbuflen_remaining -= 2;
890036d835Schristos
900036d835Schristos /*
910036d835Schristos * Now append the string for the error code.
920036d835Schristos */
930036d835Schristos #if defined(HAVE_STRERROR_S)
94*9a3414cbSchristos /*
95*9a3414cbSchristos * We have a Windows-style strerror_s().
96*9a3414cbSchristos */
97*9a3414cbSchristos errno_t err = strerror_s(p, errbuflen_remaining, errnum);
980036d835Schristos if (err != 0) {
990036d835Schristos /*
1000036d835Schristos * It doesn't appear to be documented anywhere obvious
1010036d835Schristos * what the error returns from strerror_s().
1020036d835Schristos */
1030036d835Schristos pcap_snprintf(p, errbuflen_remaining, "Error %d", errnum);
1040036d835Schristos }
105*9a3414cbSchristos #elif defined(HAVE_GNU_STRERROR_R)
106*9a3414cbSchristos /*
107*9a3414cbSchristos * We have a GNU-style strerror_r(), which is *not* guaranteed to
108*9a3414cbSchristos * do anything to the buffer handed to it, and which returns a
109*9a3414cbSchristos * pointer to the error string, which may or may not be in
110*9a3414cbSchristos * the buffer.
111*9a3414cbSchristos *
112*9a3414cbSchristos * It is, however, guaranteed to succeed.
113*9a3414cbSchristos */
114*9a3414cbSchristos char strerror_buf[PCAP_ERRBUF_SIZE];
115*9a3414cbSchristos char *errstring = strerror_r(errnum, strerror_buf, PCAP_ERRBUF_SIZE);
116*9a3414cbSchristos pcap_snprintf(p, errbuflen_remaining, "%s", errstring);
117*9a3414cbSchristos #elif defined(HAVE_POSIX_STRERROR_R)
118*9a3414cbSchristos /*
119*9a3414cbSchristos * We have a POSIX-style strerror_r(), which is guaranteed to fill
120*9a3414cbSchristos * in the buffer, but is not guaranteed to succeed.
121*9a3414cbSchristos */
122*9a3414cbSchristos int err = strerror_r(errnum, p, errbuflen_remaining);
1230036d835Schristos if (err == EINVAL) {
1240036d835Schristos /*
1250036d835Schristos * UNIX 03 says this isn't guaranteed to produce a
1260036d835Schristos * fallback error message.
1270036d835Schristos */
1280036d835Schristos pcap_snprintf(p, errbuflen_remaining, "Unknown error: %d",
1290036d835Schristos errnum);
1300036d835Schristos } else if (err == ERANGE) {
1310036d835Schristos /*
1320036d835Schristos * UNIX 03 says this isn't guaranteed to produce a
1330036d835Schristos * fallback error message.
1340036d835Schristos */
1350036d835Schristos pcap_snprintf(p, errbuflen_remaining,
1360036d835Schristos "Message for error %d is too long", errnum);
1370036d835Schristos }
1380036d835Schristos #else
1390036d835Schristos /*
1400036d835Schristos * We have neither strerror_s() nor strerror_r(), so we're
1410036d835Schristos * stuck with using pcap_strerror().
1420036d835Schristos */
1430036d835Schristos pcap_snprintf(p, errbuflen_remaining, "%s", pcap_strerror(errnum));
1440036d835Schristos #endif
1450036d835Schristos }
146*9a3414cbSchristos
147*9a3414cbSchristos #ifdef _WIN32
148*9a3414cbSchristos /*
149*9a3414cbSchristos * Generate an error message based on a format, arguments, and a
150*9a3414cbSchristos * Win32 error, with a message for the Win32 error after the formatted output.
151*9a3414cbSchristos */
152*9a3414cbSchristos void
pcap_fmt_errmsg_for_win32_err(char * errbuf,size_t errbuflen,DWORD errnum,const char * fmt,...)153*9a3414cbSchristos pcap_fmt_errmsg_for_win32_err(char *errbuf, size_t errbuflen, DWORD errnum,
154*9a3414cbSchristos const char *fmt, ...)
155*9a3414cbSchristos {
156*9a3414cbSchristos va_list ap;
157*9a3414cbSchristos size_t msglen;
158*9a3414cbSchristos char *p;
159*9a3414cbSchristos size_t errbuflen_remaining;
160*9a3414cbSchristos DWORD retval;
161*9a3414cbSchristos char win32_errbuf[PCAP_ERRBUF_SIZE+1];
162*9a3414cbSchristos
163*9a3414cbSchristos va_start(ap, fmt);
164*9a3414cbSchristos pcap_vsnprintf(errbuf, errbuflen, fmt, ap);
165*9a3414cbSchristos va_end(ap);
166*9a3414cbSchristos msglen = strlen(errbuf);
167*9a3414cbSchristos
168*9a3414cbSchristos /*
169*9a3414cbSchristos * Do we have enough space to append ": "?
170*9a3414cbSchristos * Including the terminating '\0', that's 3 bytes.
171*9a3414cbSchristos */
172*9a3414cbSchristos if (msglen + 3 > errbuflen) {
173*9a3414cbSchristos /* No - just give them what we've produced. */
174*9a3414cbSchristos return;
175*9a3414cbSchristos }
176*9a3414cbSchristos p = errbuf + msglen;
177*9a3414cbSchristos errbuflen_remaining = errbuflen - msglen;
178*9a3414cbSchristos *p++ = ':';
179*9a3414cbSchristos *p++ = ' ';
180*9a3414cbSchristos *p = '\0';
181*9a3414cbSchristos msglen += 2;
182*9a3414cbSchristos errbuflen_remaining -= 2;
183*9a3414cbSchristos
184*9a3414cbSchristos /*
185*9a3414cbSchristos * Now append the string for the error code.
186*9a3414cbSchristos *
187*9a3414cbSchristos * XXX - what language ID to use?
188*9a3414cbSchristos *
189*9a3414cbSchristos * For UN*Xes, pcap_strerror() may or may not return localized
190*9a3414cbSchristos * strings.
191*9a3414cbSchristos *
192*9a3414cbSchristos * We currently don't have localized messages for libpcap, but
193*9a3414cbSchristos * we might want to do so. On the other hand, if most of these
194*9a3414cbSchristos * messages are going to be read by libpcap developers and
195*9a3414cbSchristos * perhaps by developers of libpcap-based applications, English
196*9a3414cbSchristos * might be a better choice, so the developer doesn't have to
197*9a3414cbSchristos * get the message translated if it's in a language they don't
198*9a3414cbSchristos * happen to understand.
199*9a3414cbSchristos */
200*9a3414cbSchristos retval = FormatMessageA(FORMAT_MESSAGE_FROM_SYSTEM|FORMAT_MESSAGE_IGNORE_INSERTS|FORMAT_MESSAGE_MAX_WIDTH_MASK,
201*9a3414cbSchristos NULL, errnum, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
202*9a3414cbSchristos win32_errbuf, PCAP_ERRBUF_SIZE, NULL);
203*9a3414cbSchristos if (retval == 0) {
204*9a3414cbSchristos /*
205*9a3414cbSchristos * Failed.
206*9a3414cbSchristos */
207*9a3414cbSchristos pcap_snprintf(p, errbuflen_remaining,
208*9a3414cbSchristos "Couldn't get error message for error (%lu)", errnum);
209*9a3414cbSchristos return;
210*9a3414cbSchristos }
211*9a3414cbSchristos
212*9a3414cbSchristos pcap_snprintf(p, errbuflen_remaining, "%s (%lu)", win32_errbuf, errnum);
213*9a3414cbSchristos }
214*9a3414cbSchristos #endif
215