contrib/libpcap-0.9/etherent.c

   1 /*
   2  * Copyright (c) 1990, 1993, 1994, 1995, 1996
   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: (1) source code distributions
   7  * retain the above copyright notice and this paragraph in its entirety, (2)
   8  * distributions including binary code include the above copyright notice and
   9  * this paragraph in its entirety in the documentation or other materials
  10  * provided with the distribution, and (3) all advertising materials mentioning
  11  * features or use of this software display the following acknowledgement:
  12  * ``This product includes software developed by the University of California,
  13  * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
  14  * the University nor the names of its contributors may be used to endorse
  15  * or promote products derived from this software without specific prior
  16  * written permission.
  17  * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
  18  * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
  19  * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
  20  */
  21
  22 #ifndef lint
  23 static const char rcsid[] _U_ =
  24     "@(#) $Header: /tcpdump/master/libpcap/etherent.c,v 1.22 2003/11/15 23:23:57 guy Exp $ (LBL)";
  25 #endif
  26
  27 #ifdef HAVE_CONFIG_H
  28 #include "config.h"
  29 #endif
  30
  31 #include <sys/types.h>
  32
  33 #include <ctype.h>
  34 #include <memory.h>
  35 #include <stdio.h>
  36 #include <string.h>
  37
  38 #include "pcap-int.h"
  39
  40 #include <pcap-namedb.h>
  41
  42 #ifdef HAVE_OS_PROTO_H
  43 #include "os-proto.h"
  44 #endif
  45
  46 static inline int xdtoi(int);
  47 static inline int skip_space(FILE *);
  48 static inline int skip_line(FILE *);
  49
  50 /* Hex digit to integer. */
  51 static inline int
  52 xdtoi(c)
  53         register int c;
  54 {
  55         if (isdigit(c))
  56                 return c - '0';
  57         else if (islower(c))
  58                 return c - 'a' + 10;
  59         else
  60                 return c - 'A' + 10;
  61 }
  62
  63 static inline int
  64 skip_space(f)
  65         FILE *f;
  66 {
  67         int c;
  68
  69         do {
  70                 c = getc(f);
  71         } while (isspace(c) && c != '\n');
  72
  73         return c;
  74 }
  75
  76 static inline int
  77 skip_line(f)
  78         FILE *f;
  79 {
  80         int c;
  81
  82         do
  83                 c = getc(f);
  84         while (c != '\n' && c != EOF);
  85
  86         return c;
  87 }
  88
  89 struct pcap_etherent *
  90 pcap_next_etherent(FILE *fp)
  91 {
  92         register int c, d, i;
  93         char *bp;
  94         static struct pcap_etherent e;
  95
  96         memset((char *)&e, 0, sizeof(e));
  97         do {
  98                 /* Find addr */
  99                 c = skip_space(fp);
 100                 if (c == '\n')
 101                         continue;
 102
 103                 /* If this is a comment, or first thing on line
 104                    cannot be etehrnet address, skip the line. */
 105                 if (!isxdigit(c)) {
 106                         c = skip_line(fp);
 107                         continue;
 108                 }
 109
 110                 /* must be the start of an address */
 111                 for (i = 0; i < 6; i += 1) {
 112                         d = xdtoi(c);
 113                         c = getc(fp);
 114                         if (isxdigit(c)) {
 115                                 d <<= 4;
 116                                 d |= xdtoi(c);
 117                                 c = getc(fp);
 118                         }
 119                         e.addr[i] = d;
 120                         if (c != ':')
 121                                 break;
 122                         c = getc(fp);
 123                 }
 124                 if (c == EOF)
 125                         break;
 126
 127                 /* Must be whitespace */
 128                 if (!isspace(c)) {
 129                         c = skip_line(fp);
 130                         continue;
 131                 }
 132                 c = skip_space(fp);
 133
 134                 /* hit end of line... */
 135                 if (c == '\n')
 136                         continue;
 137
 138                 if (c == '#') {
 139                         c = skip_line(fp);
 140                         continue;
 141                 }
 142
 143                 /* pick up name */
 144                 bp = e.name;
 145                 /* Use 'd' to prevent buffer overflow. */
 146                 d = sizeof(e.name) - 1;
 147                 do {
 148                         *bp++ = c;
 149                         c = getc(fp);
 150                 } while (!isspace(c) && c != EOF && --d > 0);
 151                 *bp = '\0';
 152
 153                 /* Eat trailing junk */
 154                 if (c != '\n')
 155                         (void)skip_line(fp);
 156
 157                 return &e;
 158
 159         } while (c != EOF);
 160
 161         return (NULL);
 162 }