1 /* 2 * Copyright (c) 1993, 1994, 1995, 1996, 1997, 1998 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the Computer Systems 16 * Engineering Group at Lawrence Berkeley Laboratory. 17 * 4. Neither the name of the University nor of the Laboratory may be used 18 * to endorse or promote products derived from this software without 19 * specific prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 */ 33 34 /* 35 * Utilities for message formatting used both by libpcap and rpcapd. 36 */ 37 38 #ifdef HAVE_CONFIG_H 39 #include <config.h> 40 #endif 41 42 #include "ftmacros.h" 43 44 #include <stddef.h> 45 #include <stdarg.h> 46 #include <stdio.h> 47 #include <string.h> 48 #include <errno.h> 49 50 #include <pcap/pcap.h> 51 52 #include "portability.h" 53 54 #include "fmtutils.h" 55 56 /* 57 * Generate an error message based on a format, arguments, and an 58 * errno, with a message for the errno after the formatted output. 59 */ 60 void 61 pcap_fmt_errmsg_for_errno(char *errbuf, size_t errbuflen, int errnum, 62 const char *fmt, ...) 63 { 64 va_list ap; 65 size_t msglen; 66 char *p; 67 size_t errbuflen_remaining; 68 #if defined(HAVE_STRERROR_S) 69 errno_t err; 70 #elif defined(HAVE_STRERROR_R) 71 int err; 72 #endif 73 74 va_start(ap, fmt); 75 pcap_vsnprintf(errbuf, errbuflen, fmt, ap); 76 va_end(ap); 77 msglen = strlen(errbuf); 78 79 /* 80 * Do we have enough space to append ": "? 81 * Including the terminating '\0', that's 3 bytes. 82 */ 83 if (msglen + 3 > errbuflen) { 84 /* No - just give them what we've produced. */ 85 return; 86 } 87 p = errbuf + msglen; 88 errbuflen_remaining = errbuflen - msglen; 89 *p++ = ':'; 90 *p++ = ' '; 91 *p = '\0'; 92 msglen += 2; 93 errbuflen_remaining -= 2; 94 95 /* 96 * Now append the string for the error code. 97 */ 98 #if defined(HAVE_STRERROR_S) 99 err = strerror_s(p, errbuflen_remaining, errnum); 100 if (err != 0) { 101 /* 102 * It doesn't appear to be documented anywhere obvious 103 * what the error returns from strerror_s(). 104 */ 105 pcap_snprintf(p, errbuflen_remaining, "Error %d", errnum); 106 } 107 #elif defined(HAVE_STRERROR_R) 108 err = strerror_r(errnum, p, errbuflen_remaining); 109 if (err == EINVAL) { 110 /* 111 * UNIX 03 says this isn't guaranteed to produce a 112 * fallback error message. 113 */ 114 pcap_snprintf(p, errbuflen_remaining, "Unknown error: %d", 115 errnum); 116 } else if (err == ERANGE) { 117 /* 118 * UNIX 03 says this isn't guaranteed to produce a 119 * fallback error message. 120 */ 121 pcap_snprintf(p, errbuflen_remaining, 122 "Message for error %d is too long", errnum); 123 } 124 #else 125 /* 126 * We have neither strerror_s() nor strerror_r(), so we're 127 * stuck with using pcap_strerror(). 128 */ 129 pcap_snprintf(p, errbuflen_remaining, "%s", pcap_strerror(errnum)); 130 #endif 131 } 132