/* * 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; 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) /* * We have a Windows-style strerror_s(). */ errno_t 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_GNU_STRERROR_R) /* * We have a GNU-style strerror_r(), which is *not* guaranteed to * do anything to the buffer handed to it, and which returns a * pointer to the error string, which may or may not be in * the buffer. * * It is, however, guaranteed to succeed. */ char strerror_buf[PCAP_ERRBUF_SIZE]; char *errstring = strerror_r(errnum, strerror_buf, PCAP_ERRBUF_SIZE); pcap_snprintf(p, errbuflen_remaining, "%s", errstring); #elif defined(HAVE_POSIX_STRERROR_R) /* * We have a POSIX-style strerror_r(), which is guaranteed to fill * in the buffer, but is not guaranteed to succeed. */ int 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 } #ifdef _WIN32 /* * Generate an error message based on a format, arguments, and a * Win32 error, with a message for the Win32 error after the formatted output. */ void pcap_fmt_errmsg_for_win32_err(char *errbuf, size_t errbuflen, DWORD errnum, const char *fmt, ...) { va_list ap; size_t msglen; char *p; size_t errbuflen_remaining; DWORD retval; char win32_errbuf[PCAP_ERRBUF_SIZE+1]; 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. * * XXX - what language ID to use? * * For UN*Xes, pcap_strerror() may or may not return localized * strings. * * We currently don't have localized messages for libpcap, but * we might want to do so. On the other hand, if most of these * messages are going to be read by libpcap developers and * perhaps by developers of libpcap-based applications, English * might be a better choice, so the developer doesn't have to * get the message translated if it's in a language they don't * happen to understand. */ retval = FormatMessageA(FORMAT_MESSAGE_FROM_SYSTEM|FORMAT_MESSAGE_IGNORE_INSERTS|FORMAT_MESSAGE_MAX_WIDTH_MASK, NULL, errnum, MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT), win32_errbuf, PCAP_ERRBUF_SIZE, NULL); if (retval == 0) { /* * Failed. */ pcap_snprintf(p, errbuflen_remaining, "Couldn't get error message for error (%lu)", errnum); return; } pcap_snprintf(p, errbuflen_remaining, "%s (%lu)", win32_errbuf, errnum); } #endif