2 * Code for reading and writing the filters file.
4 * $Id: filters.c,v 1.5 2001/02/03 06:03:42 guy Exp $
6 * Ethereal - Network traffic analyzer
7 * By Gerald Combs <gerald@zing.org>
8 * Copyright 1998 Gerald Combs
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License
13 * as published by the Free Software Foundation; either version 2
14 * of the License, or (at your option) any later version.
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU General Public License for more details.
21 * You should have received a copy of the GNU General Public License
22 * along with this program; if not, write to the Free Software
23 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
35 #ifdef HAVE_SYS_STAT_H
44 #include <direct.h> /* to declare "mkdir()" on Windows */
55 * Old filter file name.
57 #define FILTER_FILE_NAME "filters"
60 * Capture filter file name.
62 #define CFILTER_FILE_NAME "cfilters"
65 * Display filter file name.
67 #define DFILTER_FILE_NAME "dfilters"
70 * List of capture filters.
72 static GList *capture_filters = NULL;
75 * List of display filters.
77 static GList *display_filters = NULL;
80 * Read in a list of filters.
82 * On success, "*pref_path_return" is set to NULL.
83 * On error, "*pref_path_return" is set to point to the pathname of
84 * the file we tried to read - it should be freed by our caller -
85 * and "*errno_return" is set to the error.
88 #define INIT_BUF_SIZE 128
91 read_filter_list(filter_list_type_t list, char **pref_path_return,
94 char *ff_path, *ff_dir = PF_DIR, *ff_name;
100 char *filt_name, *filt_expr;
101 int filt_name_len, filt_expr_len;
102 int filt_name_index, filt_expr_index;
105 *pref_path_return = NULL; /* assume no error */
110 ff_name = CFILTER_FILE_NAME;
111 flp = &capture_filters;
115 ff_name = DFILTER_FILE_NAME;
116 flp = &display_filters;
120 g_assert_not_reached();
124 /* To do: generalize this */
125 ff_path = (gchar *) g_malloc(strlen(get_home_dir()) + strlen(ff_dir) +
126 strlen(ff_name) + 4);
127 sprintf(ff_path, "%s/%s/%s", get_home_dir(), ff_dir, ff_name);
129 if ((ff = fopen(ff_path, "r")) == NULL) {
131 * Did that fail because we the file didn't exist?
133 if (errno != ENOENT) {
137 *pref_path_return = ff_path;
138 *errno_return = errno;
143 * Yes. See if there's a "filters" file; if so, read it.
144 * This means that a user will start out with their capture and
145 * display filter lists being identical; each list may contain
146 * filters that don't belong in that list. The user can edit
147 * the filter lists, and delete the ones that don't belong in
150 sprintf(ff_path, "%s/%s/%s", get_home_dir(), ff_dir, FILTER_FILE_NAME);
151 if ((ff = fopen(ff_path, "r")) == NULL) {
153 * Well, that didn't work, either. Just give up.
154 * Return an error if the file existed but we couldn't open it.
156 if (errno != ENOENT) {
157 *pref_path_return = ff_path;
158 *errno_return = errno;
164 /* If we already have a list of filters, discard it. */
166 fl_ent = g_list_first(*flp);
167 while (fl_ent != NULL) {
168 filt = (filter_def *) fl_ent->data;
170 g_free(filt->strval);
172 fl_ent = fl_ent->next;
178 /* Allocate the filter name buffer. */
179 filt_name_len = INIT_BUF_SIZE;
180 filt_name = g_malloc(filt_name_len + 1);
181 filt_expr_len = INIT_BUF_SIZE;
182 filt_expr = g_malloc(filt_expr_len + 1);
185 /* Lines in a filter file are of the form
189 where "name" is a name, in quotes - backslashes in the name
190 escape the next character, so quotes and backslashes can appear
191 in the name - and "expression" is a filter expression, not in
192 quotes, running to the end of the line. */
194 /* Skip over leading white space, if any. */
195 while ((c = getc(ff)) != EOF && isspace(c)) {
198 line++; /* next line */
204 break; /* Nothing more to read */
206 /* "c" is the first non-white-space character.
207 If it's not a quote, it's an error. */
209 g_warning("'%s' line %d doesn't have a quoted filter name.", ff_path,
212 c = getc(ff); /* skip to the end of the line */
213 line++; /* next line */
217 /* Get the name of the filter. */
221 if (c == EOF || c == '\n')
222 break; /* End of line - or end of file */
225 if (filt_name_index >= filt_name_len) {
226 /* Filter name buffer isn't long enough; double its length. */
228 filt_name = g_realloc(filt_name, filt_name_len + 1);
230 filt_name[filt_name_index] = '\0';
234 /* Next character is escaped */
236 if (c == EOF || c == '\n')
237 break; /* End of line - or end of file */
239 /* Add this character to the filter name string. */
240 if (filt_name_index >= filt_name_len) {
241 /* Filter name buffer isn't long enough; double its length. */
243 filt_name = g_realloc(filt_name, filt_name_len + 1);
245 filt_name[filt_name_index] = c;
251 /* EOF, not error; no newline seen before EOF */
252 g_warning("'%s' line %d doesn't have a newline.", ff_path,
255 break; /* nothing more to read */
259 /* No newline seen before end-of-line */
260 g_warning("'%s' line %d doesn't have a closing quote.", ff_path,
262 line++; /* next line */
266 /* Skip over separating white space, if any. */
267 while ((c = getc(ff)) != EOF && isspace(c)) {
269 /* No filter expression */
270 g_warning("'%s' line %d doesn't have a filter expression.", ff_path,
272 line++; /* next line */
279 /* EOF, not error; no newline seen before EOF */
280 g_warning("'%s' line %d doesn't have a newline.", ff_path,
283 break; /* nothing more to read */
286 /* "c" is the first non-white-space character; it's the first
287 character of the filter expression. */
290 /* Add this character to the filter expression string. */
291 if (filt_expr_index >= filt_expr_len) {
292 /* Filter expressioin buffer isn't long enough; double its length. */
294 filt_expr = g_realloc(filt_expr, filt_expr_len + 1);
296 filt_expr[filt_expr_index] = c;
299 /* Get the next character. */
301 if (c == EOF || c == '\n')
307 /* EOF, not error; no newline seen before EOF */
308 g_warning("'%s' line %d doesn't have a newline.", ff_path,
311 break; /* nothing more to read */
314 /* We saw the ending newline; terminate the filter expression string */
315 if (filt_expr_index >= filt_expr_len) {
316 /* Filter expressioin buffer isn't long enough; double its length. */
318 filt_expr = g_realloc(filt_expr, filt_expr_len + 1);
320 filt_expr[filt_expr_index] = '\0';
322 /* Add the new filter to the list of filters */
323 filt = (filter_def *) g_malloc(sizeof(filter_def));
324 filt->name = g_strdup(filt_name);
325 filt->strval = g_strdup(filt_expr);
326 *flp = g_list_append(*flp, filt);
329 *pref_path_return = ff_path;
330 *errno_return = errno;
339 * Get a pointer to a list of filters.
342 get_filter_list(filter_list_type_t list)
349 flp = &capture_filters;
353 flp = &display_filters;
357 g_assert_not_reached();
364 * Get a pointer to the first entry in a filter list.
367 get_filter_list_first(filter_list_type_t list)
371 flp = get_filter_list(list);
372 return g_list_first(*flp);
376 * Add a new filter to the end of a list.
377 * Returns a pointer to the newly-added entry.
380 add_to_filter_list(filter_list_type_t list, char *name, char *expression)
385 flp = get_filter_list(list);
386 filt = (filter_def *) g_malloc(sizeof(filter_def));
387 filt->name = g_strdup(name);
388 filt->strval = g_strdup(expression);
389 *flp = g_list_append(*flp, filt);
390 return g_list_last(*flp);
394 * Remove a filter from a list.
397 remove_from_filter_list(filter_list_type_t list, GList *fl_entry)
402 flp = get_filter_list(list);
403 filt = (filter_def *) fl_entry->data;
405 g_free(filt->strval);
407 *flp = g_list_remove_link(*flp, fl_entry);
411 * Write out a list of filters.
413 * On success, "*pref_path_return" is set to NULL.
414 * On error, "*pref_path_return" is set to point to the pathname of
415 * the file we tried to read - it should be freed by our caller -
416 * and "*errno_return" is set to the error.
419 save_filter_list(filter_list_type_t list, char **pref_path_return,
422 gchar *ff_path, *ff_path_new, *ff_dir = PF_DIR, *ff_name;
431 *pref_path_return = NULL; /* assume no error */
436 ff_name = CFILTER_FILE_NAME;
437 fl = capture_filters;
441 ff_name = DFILTER_FILE_NAME;
442 fl = display_filters;
446 g_assert_not_reached();
450 path_length = strlen(get_home_dir()) + strlen(ff_dir) + strlen(ff_name)
452 ff_path = (gchar *) g_malloc(path_length);
453 sprintf(ff_path, "%s/%s", get_home_dir(), ff_dir);
455 if (stat(ff_path, &s_buf) != 0)
459 mkdir(ff_path, 0755);
462 sprintf(ff_path, "%s/%s/%s", get_home_dir(), ff_dir, ff_name);
464 /* Write to "XXX.new", and rename if that succeeds.
465 That means we don't trash the file if we fail to write it out
467 ff_path_new = (gchar *) g_malloc(path_length);
468 sprintf(ff_path_new, "%s/%s/%s.new", get_home_dir(), ff_dir, ff_name);
470 if ((ff = fopen(ff_path_new, "w")) == NULL) {
471 *pref_path_return = ff_path;
472 *errno_return = errno;
476 flp = g_list_first(fl);
478 filt = (filter_def *) flp->data;
480 /* Write out the filter name as a quoted string; escape any quotes
483 for (p = (guchar *)filt->name; (c = *p) != '\0'; p++) {
484 if (c == '"' || c == '\\')
490 /* Separate the filter name and value with a space. */
493 /* Write out the filter expression and a newline. */
494 fprintf(ff, "%s\n", filt->strval);
496 *pref_path_return = ff_path;
497 *errno_return = errno;
505 if (fclose(ff) == EOF) {
506 *pref_path_return = ff_path;
507 *errno_return = errno;
513 /* XXX - does "rename()" exist on Win32? If so, does it remove the
514 target first? If so, does that mean it's not atomic? */
515 if (rename(ff_path_new, ff_path) < 0) {
516 *pref_path_return = ff_path;
517 *errno_return = errno;