Linux Cubed Series 7: Sunsite/Linux Cubed Series 7 - Sunsite Vol 1.iso/system/network/manageme/tcpdump-.7/tcpdump-/tcpdump-richard-1.7/libpcap-0.0/scanner.l

Lex Description | 1995-04-03 | 4.1 KB | 195 lines

%{
/*
 * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994
 *    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: (1) source code distributions
 * retain the above copyright notice and this paragraph in its entirety, (2)
 * distributions including binary code include the above copyright notice and
 * this paragraph in its entirety in the documentation or other materials
 * provided with the distribution, and (3) all advertising materials mentioning
 * features or use of this software display the following acknowledgement:
 * ``This product includes software developed by the University of California,
 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
 * the University nor the names of its contributors may be used to endorse
 * or promote products derived from this software without specific prior
 * written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */

#ifndef lint
static char rcsid[] =
    "@(#) $Header: scanner.l,v 1.40 94/06/10 17:21:44 mccanne Exp $ (LBL)";
#endif

#include <sys/types.h>
#include <sys/time.h>

#include <ctype.h>
#include <unistd.h>
#include <pcap.h>
#include <pcap-namedb.h>

#include "gencode.h"
#include "tokdefs.h"

#ifndef __GNUC__
#define inline
#endif

static int stoi(char *);
static inline int xdtoi(int);

#ifdef FLEX_SCANNER
#undef YY_INPUT
#define YY_INPUT(buf, result, max)\
 {\
    char *src = in_buffer;\
    int i;\
\
    if (*src == 0)\
        result = YY_NULL;\
    else {\
        for (i = 0; *src && i < max; ++i)\
            buf[i] = *src++;\
        in_buffer += i;\
        result = i;\
    }\
 }
#else
#undef getc
#define getc(fp)  (*in_buffer == 0 ? EOF : *in_buffer++)
#endif

#define yylval pcap_lval
extern YYSTYPE yylval;

static char *in_buffer;

%}

N        ([0-9]+|(0X|0x)[0-9A-Fa-f]+)
B        ([0-9A-Fa-f][0-9A-Fa-f]?)

%a 3000

%%
dst        return DST;
src        return SRC;

link|ether|ppp|slip  return LINK;
fddi        return LINK;
arp        return ARP;
rarp        return RARP;
ip        return IP;
tcp        return TCP;
udp        return UDP;
icmp        return ICMP;

decnet        return DECNET;
lat        return LAT;
moprc        return MOPRC;
mopdl        return MOPDL;

host        return HOST;
net        return NET;
port        return PORT;
proto        return PROTO;

gateway        return GATEWAY;

less        return LESS;
greater        return GREATER;
byte        return BYTE;
broadcast    return TK_BROADCAST;
multicast    return TK_MULTICAST;

and|"&&"    return AND;
or|"||"        return OR;
not        return '!';

len|length    return LEN;
inbound        return INBOUND;
outbound    return OUTBOUND;

[ \n\t]            ;
[+\-*/:\[\]!<>()&|=]    return yytext[0];
">="            return GEQ;
"<="            return LEQ;
"!="            return NEQ;
"=="            return '=';
"<<"            return LSH;
">>"            return RSH;
{N}            { yylval.i = stoi((char *)yytext); return NUM; }
({N}\.{N})|({N}\.{N}\.{N})|({N}\.{N}\.{N}\.{N})    {
            yylval.s = sdup((char *)yytext); return HID;
}
{B}:{B}:{B}:{B}:{B}:{B} { yylval.e = pcap_ether_aton((char *)yytext);
              return EID; }
{B}:+({B}:+)+        { bpf_error("bogus ethernet address %s", yytext); }
[A-Za-z][-_.A-Za-z0-9]*    { yylval.s = sdup((char *)yytext); return ID; }
"\\"[^ !()\n\t]+    { yylval.s = sdup((char *)yytext + 1); return ID; }
[^ \[\]\t\n\-_.A-Za-z0-9!<>()&|=]+    { bpf_error("illegal token: %s\n", yytext); }
.            { bpf_error("illegal char '%c'", *yytext); }
%%
void
lex_init(buf)
    char *buf;
{
    in_buffer = buf;
}

/*
 * Also define a yywrap.  Note that if we're using flex, it will
 * define a macro to map this identifier to pcap_wrap.
 */
int
yywrap()
{
    return 1;
}

/* Hex digit to integer. */
static inline int
xdtoi(c)
    register int c;
{
    if (isdigit(c))
        return c - '0';
    else if (islower(c))
        return c - 'a' + 10;
    else
        return c - 'A' + 10;
}

/*
 * Convert string to integer.  Just like atoi(), but checks for
 * preceding 0x or 0 and uses hex or octal instead of decimal.
 */
static int
stoi(s)
    char *s;
{
    int base = 10;
    int n = 0;

    if (*s == '0') {
        if (s[1] == 'x' || s[1] == 'X') {
            s += 2;
            base = 16;
        }
        else {
            base = 8;
            s += 1;
        }
    }
    while (*s)
        n = n * base + xdtoi(*s++);

    return n;
}