4 * Scanner for display filters
6 * $Id: dfilter-scanner.l,v 1.21 1999/10/15 04:22:47 itojun Exp $
8 * Ethereal - Network traffic analyzer
9 * By Gerald Combs <gerald@zing.org>
10 * Copyright 1998 Gerald Combs
13 * This program is free software; you can redistribute it and/or
14 * modify it under the terms of the GNU General Public License
15 * as published by the Free Software Foundation; either version 2
16 * of the License, or (at your option) any later version.
18 * This program is distributed in the hope that it will be useful,
19 * but WITHOUT ANY WARRANTY; without even the implied warranty of
20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
21 * GNU General Public License for more details.
23 * You should have received a copy of the GNU General Public License
24 * along with this program; if not, write to the Free Software
25 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
32 #ifdef HAVE_SYS_TYPES_H
33 # include <sys/types.h>
56 #include "dfilter-int.h"
58 #include "dfilter-grammar.h"
60 /* Flex has a few routines which help us get the scanner to read
61 * from a string rather than from a file. POSIX lex only provides
62 * for reading from a file; any method of reading from a string
63 * is inherently non-portable. Besides reading from a string,
64 * we have to worry about resetting the scanner after a bad
65 * parse; this too is non-portable. Combine the reset with
66 * a string input, and you have major non-portability. I'll provide
67 * the routines for flex here. If you really want to modify the
68 * scanner and use a non-flex lex implementation, you may
69 * add more ifdef's below.
73 /* Flex has built-in support for using a string as an input source
74 * instead of using a file. Nice!
76 YY_BUFFER_STATE string_input_buffer;
80 static char *in_buffer;
82 #define getc(fp) (*in_buffer == 0 ? EOF : *in_buffer++)
95 [\t\n ]+ /* ignore whitespace */
98 and|\&\& { dfilter_lval.operand = TOK_AND; return TOK_AND; }
99 or|\|\| { dfilter_lval.operand = TOK_OR; return TOK_OR; }
100 not|\! { dfilter_lval.operand = TOK_NOT; return TOK_NOT; }
101 xor|\^\^ { dfilter_lval.operand = TOK_XOR; return TOK_XOR; }
102 eq|\=\= { dfilter_lval.operand = TOK_EQ; return TOK_EQ; }
103 ne|\!\= { dfilter_lval.operand = TOK_NE; return TOK_NE; }
104 gt|\> { dfilter_lval.operand = TOK_GT; return TOK_GT; }
105 ge|\>\= { dfilter_lval.operand = TOK_GE; return TOK_GE; }
106 lt|\< { dfilter_lval.operand = TOK_LT; return TOK_LT; }
107 le|\<\= { dfilter_lval.operand = TOK_LE; return TOK_LE; }
109 \[{whitespace}*-?[0-9]+{whitespace}*:{whitespace}*[0-9]+{whitespace}*\] { /* range [ x : y ] */
111 char *byterange_string = g_strdup(yytext);
112 char *s = byterange_string + 1; /* I don't want the first '[' */
115 /* Get the offset from the string */
116 if ((p = strtok(s, ":"))) {
117 dfilter_lval.byte_range.offset = strtol(p, NULL, 10);
120 g_free(byterange_string);
124 /* Get the Length from the string */
125 if ((p = strtok(NULL, "]"))) {
126 dfilter_lval.byte_range.length = strtoul(p, NULL, 10);
129 g_free(byterange_string);
132 g_free(byterange_string);
133 return T_VAL_BYTE_RANGE;
136 \[{whitespace}*-?[0-9]+{whitespace}*\] { /* range [ x ] */
138 char *byterange_string = g_strdup(yytext);
139 char *s = byterange_string + 1; /* I don't want the first '[' */
142 /* Get the offset from the string */
143 if ((p = strtok(s, "]"))) {
144 dfilter_lval.byte_range.offset = strtol(p, NULL, 10);
147 g_free(byterange_string);
151 dfilter_lval.byte_range.length = 0;
152 g_free(byterange_string);
153 return T_VAL_BYTE_RANGE;
156 {hex}({hexsep}{hex})+ { /* byte string, any length */
157 dfilter_lval.string = g_strdup(yytext);
158 return T_VAL_BYTE_STRING;
162 [A-Za-z0-9\:][A-Za-z0-9\.\_\-\:]+ {
163 /* looks like a protocol, field name, or hostname */
167 dfilter_lval.variable.id = dfilter_lookup_token(yytext);
168 if (dfilter_lval.variable.id < 0) {
169 dfilter_lval.string = g_strdup(yytext);
170 return T_VAL_UNQUOTED_STRING;
173 ftype = proto_registrar_get_ftype(dfilter_lval.variable.id);
179 retval = T_FT_BOOLEAN;
185 retval = T_FT_UINT16;
188 retval = T_FT_UINT32;
200 dfilter_fail("Sorry, you can't filter on field \"%s\", as we don't yet support filtering on floating-point values.",
204 case FT_ABSOLUTE_TIME:
205 dfilter_fail("Sorry, you can't filter on field \"%s\", as we don't yet support filtering on time-of-day values.",
209 case FT_RELATIVE_TIME:
210 dfilter_fail("Sorry, you can't filter on field \"%s\", as we don't yet support filtering on time-delta values.",
215 dfilter_fail("Sorry, you can't filter on field \"%s\", as we don't yet support filtering on string values.",
232 retval = T_FT_IPXNET;
235 printf("ftype for %s is %d\n", yytext, ftype);
236 g_assert_not_reached();
240 dfilter_lval.variable.type = retval;
244 {minus}?[0-9]+ { /* decimal or octal values */
245 dfilter_lval.string = g_strdup(yytext);
246 return T_VAL_NUMBER_STRING;
250 0[xX][A-Fa-f0-9]+ { /* hex values */
251 dfilter_lval.string = g_strdup(yytext);
252 return T_VAL_NUMBER_STRING;
256 dfilter_lval.string = g_strdup(yytext);
257 return T_VAL_UNQUOTED_STRING;
263 /* Resets scanner and assigns the char* argument
264 * as the text to scan
267 dfilter_scanner_text(char *text)
270 string_input_buffer = yy_scan_string(text);
277 dfilter_scanner_cleanup(void)
280 yy_delete_buffer(string_input_buffer);
282 /* There is no standard way to reset a lex scanner.
283 * This is necessary after a failed parse on a syntactically
284 * incorrect display filter. You have to reset the scanner
285 * so that yy_lex() doesn't start scanning from the middle
286 * of the previous input string.
291 /* Flex has an option '%option noyywrap' so that I don't have to
292 * provide this yywrap function, but in order to maintain portability,
293 * I'll just use this yywrap() function.
298 return 1; /* stop at EOF, instead of looking for next file */
301 /* converts a string representing a byte array
304 * Returns a non-null GByteArray pointer on success, NULL on failure.
307 byte_str_to_guint8_array(const char *s)
311 char *byte_str = g_strdup(s); /* local copy of string */
314 barray = g_byte_array_new();
315 /* XXX - don't use global_df, but pass in pointer to GSList* */
316 global_df->list_of_byte_arrays = g_slist_append(global_df->list_of_byte_arrays, barray);
318 byte_str = g_strdup(s);
320 while ((p = strtok(str, "-:."))) {
321 val = (guint8) strtoul(p, NULL, 16);
322 g_byte_array_append(barray, &val, 1);
324 /* subsequent calls to strtok() require NULL as arg 1 */