Move var declaration for older C compilers.
[rsync.git] / exclude.c
1 /*
2  * The filter include/exclude routines.
3  *
4  * Copyright (C) 1996-2001 Andrew Tridgell <tridge@samba.org>
5  * Copyright (C) 1996 Paul Mackerras
6  * Copyright (C) 2002 Martin Pool
7  * Copyright (C) 2003-2009 Wayne Davison
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 3 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License along
20  * with this program; if not, visit the http://fsf.org website.
21  */
22
23 #include "rsync.h"
24
25 extern int am_server;
26 extern int am_sender;
27 extern int eol_nulls;
28 extern int io_error;
29 extern int local_server;
30 extern int prune_empty_dirs;
31 extern int ignore_perishable;
32 extern int delete_mode;
33 extern int delete_excluded;
34 extern int cvs_exclude;
35 extern int sanitize_paths;
36 extern int protocol_version;
37 extern int module_id;
38
39 extern char curr_dir[MAXPATHLEN];
40 extern unsigned int curr_dir_len;
41 extern unsigned int module_dirlen;
42
43 filter_rule_list filter_list = { .debug_type = "" };
44 filter_rule_list cvs_filter_list = { .debug_type = " [global CVS]" };
45 filter_rule_list daemon_filter_list = { .debug_type = " [daemon]" };
46
47 /* Need room enough for ":MODS " prefix plus some room to grow. */
48 #define MAX_RULE_PREFIX (16)
49
50 #define SLASH_WILD3_SUFFIX "/***"
51
52 /* The dirbuf is set by push_local_filters() to the current subdirectory
53  * relative to curr_dir that is being processed.  The path always has a
54  * trailing slash appended, and the variable dirbuf_len contains the length
55  * of this path prefix.  The path is always absolute. */
56 static char dirbuf[MAXPATHLEN+1];
57 static unsigned int dirbuf_len = 0;
58 static int dirbuf_depth;
59
60 /* This is True when we're scanning parent dirs for per-dir merge-files. */
61 static BOOL parent_dirscan = False;
62
63 /* This array contains a list of all the currently active per-dir merge
64  * files.  This makes it easier to save the appropriate values when we
65  * "push" down into each subdirectory. */
66 static filter_rule **mergelist_parents;
67 static int mergelist_cnt = 0;
68 static int mergelist_size = 0;
69
70 /* Each filter_list_struct describes a singly-linked list by keeping track
71  * of both the head and tail pointers.  The list is slightly unusual in that
72  * a parent-dir's content can be appended to the end of the local list in a
73  * special way:  the last item in the local list has its "next" pointer set
74  * to point to the inherited list, but the local list's tail pointer points
75  * at the end of the local list.  Thus, if the local list is empty, the head
76  * will be pointing at the inherited content but the tail will be NULL.  To
77  * help you visualize this, here are the possible list arrangements:
78  *
79  * Completely Empty                     Local Content Only
80  * ==================================   ====================================
81  * head -> NULL                         head -> Local1 -> Local2 -> NULL
82  * tail -> NULL                         tail -------------^
83  *
84  * Inherited Content Only               Both Local and Inherited Content
85  * ==================================   ====================================
86  * head -> Parent1 -> Parent2 -> NULL   head -> L1 -> L2 -> P1 -> P2 -> NULL
87  * tail -> NULL                         tail ---------^
88  *
89  * This means that anyone wanting to traverse the whole list to use it just
90  * needs to start at the head and use the "next" pointers until it goes
91  * NULL.  To add new local content, we insert the item after the tail item
92  * and update the tail (obviously, if "tail" was NULL, we insert it at the
93  * head).  To clear the local list, WE MUST NOT FREE THE INHERITED CONTENT
94  * because it is shared between the current list and our parent list(s).
95  * The easiest way to handle this is to simply truncate the list after the
96  * tail item and then free the local list from the head.  When inheriting
97  * the list for a new local dir, we just save off the filter_list_struct
98  * values (so we can pop back to them later) and set the tail to NULL.
99  */
100
101 static void teardown_mergelist(filter_rule *ex)
102 {
103         if (DEBUG_GTE(FILTER, 2)) {
104                 rprintf(FINFO, "[%s] deactivating mergelist #%d%s\n",
105                         who_am_i(), mergelist_cnt - 1,
106                         ex->u.mergelist->debug_type);
107         }
108
109         /* We should deactivate mergelists in LIFO order. */
110         assert(mergelist_cnt > 0);
111         assert(ex == mergelist_parents[mergelist_cnt - 1]);
112
113         /* The parent_dirscan filters should have been freed. */
114         assert(ex->u.mergelist->parent_dirscan_head == NULL);
115
116         free(ex->u.mergelist->debug_type);
117         free(ex->u.mergelist);
118         mergelist_cnt--;
119 }
120
121 static void free_filter(filter_rule *ex)
122 {
123         free(ex->pattern);
124         free(ex);
125 }
126
127 static void free_filters(filter_rule *head)
128 {
129         filter_rule *rev_head = NULL;
130
131         /* Reverse the list so we deactivate mergelists in the proper LIFO
132          * order. */
133         while (head) {
134                 filter_rule *next = head->next;
135                 head->next = rev_head;
136                 rev_head = head;
137                 head = next;
138         }
139
140         while (rev_head) {
141                 filter_rule *prev = rev_head->next;
142                 /* Tear down mergelists here, not in free_filter, so that we
143                  * affect only real filter lists and not temporarily allocated
144                  * filters. */
145                 if (rev_head->rflags & FILTRULE_PERDIR_MERGE)
146                         teardown_mergelist(rev_head);
147                 free_filter(rev_head);
148                 rev_head = prev;
149         }
150 }
151
152 /* Build a filter structure given a filter pattern.  The value in "pat"
153  * is not null-terminated.  "rule" is either held or freed, so the
154  * caller should not free it. */
155 static void add_rule(filter_rule_list *listp, const char *pat, unsigned int pat_len,
156                      filter_rule *rule, int xflags)
157 {
158         const char *cp;
159         unsigned int pre_len, suf_len, slash_cnt = 0;
160
161         if (DEBUG_GTE(FILTER, 2)) {
162                 rprintf(FINFO, "[%s] add_rule(%s%.*s%s)%s\n",
163                         who_am_i(), get_rule_prefix(rule, pat, 0, NULL),
164                         (int)pat_len, pat,
165                         (rule->rflags & FILTRULE_DIRECTORY) ? "/" : "",
166                         listp->debug_type);
167         }
168
169         /* These flags also indicate that we're reading a list that
170          * needs to be filtered now, not post-filtered later. */
171         if (xflags & (XFLG_ANCHORED2ABS|XFLG_ABS_IF_SLASH)
172                 && (rule->rflags & FILTRULES_SIDES)
173                         == (am_sender ? FILTRULE_RECEIVER_SIDE : FILTRULE_SENDER_SIDE)) {
174                 /* This filter applies only to the other side.  Drop it. */
175                 free_filter(rule);
176                 return;
177         }
178
179         if (pat_len > 1 && pat[pat_len-1] == '/') {
180                 pat_len--;
181                 rule->rflags |= FILTRULE_DIRECTORY;
182         }
183
184         for (cp = pat; cp < pat + pat_len; cp++) {
185                 if (*cp == '/')
186                         slash_cnt++;
187         }
188
189         if (!(rule->rflags & (FILTRULE_ABS_PATH | FILTRULE_MERGE_FILE))
190          && ((xflags & (XFLG_ANCHORED2ABS|XFLG_ABS_IF_SLASH) && *pat == '/')
191           || (xflags & XFLG_ABS_IF_SLASH && slash_cnt))) {
192                 rule->rflags |= FILTRULE_ABS_PATH;
193                 if (*pat == '/')
194                         pre_len = dirbuf_len - module_dirlen - 1;
195                 else
196                         pre_len = 0;
197         } else
198                 pre_len = 0;
199
200         /* The daemon wants dir-exclude rules to get an appended "/" + "***". */
201         if (xflags & XFLG_DIR2WILD3
202          && BITS_SETnUNSET(rule->rflags, FILTRULE_DIRECTORY, FILTRULE_INCLUDE)) {
203                 rule->rflags &= ~FILTRULE_DIRECTORY;
204                 suf_len = sizeof SLASH_WILD3_SUFFIX - 1;
205         } else
206                 suf_len = 0;
207
208         if (!(rule->pattern = new_array(char, pre_len + pat_len + suf_len + 1)))
209                 out_of_memory("add_rule");
210         if (pre_len) {
211                 memcpy(rule->pattern, dirbuf + module_dirlen, pre_len);
212                 for (cp = rule->pattern; cp < rule->pattern + pre_len; cp++) {
213                         if (*cp == '/')
214                                 slash_cnt++;
215                 }
216         }
217         strlcpy(rule->pattern + pre_len, pat, pat_len + 1);
218         pat_len += pre_len;
219         if (suf_len) {
220                 memcpy(rule->pattern + pat_len, SLASH_WILD3_SUFFIX, suf_len+1);
221                 pat_len += suf_len;
222                 slash_cnt++;
223         }
224
225         if (strpbrk(rule->pattern, "*[?")) {
226                 rule->rflags |= FILTRULE_WILD;
227                 if ((cp = strstr(rule->pattern, "**")) != NULL) {
228                         rule->rflags |= FILTRULE_WILD2;
229                         /* If the pattern starts with **, note that. */
230                         if (cp == rule->pattern)
231                                 rule->rflags |= FILTRULE_WILD2_PREFIX;
232                         /* If the pattern ends with ***, note that. */
233                         if (pat_len >= 3
234                          && rule->pattern[pat_len-3] == '*'
235                          && rule->pattern[pat_len-2] == '*'
236                          && rule->pattern[pat_len-1] == '*')
237                                 rule->rflags |= FILTRULE_WILD3_SUFFIX;
238                 }
239         }
240
241         if (rule->rflags & FILTRULE_PERDIR_MERGE) {
242                 filter_rule_list *lp;
243                 unsigned int len;
244                 int i;
245
246                 if ((cp = strrchr(rule->pattern, '/')) != NULL)
247                         cp++;
248                 else
249                         cp = rule->pattern;
250
251                 /* If the local merge file was already mentioned, don't
252                  * add it again. */
253                 for (i = 0; i < mergelist_cnt; i++) {
254                         filter_rule *ex = mergelist_parents[i];
255                         const char *s = strrchr(ex->pattern, '/');
256                         if (s)
257                                 s++;
258                         else
259                                 s = ex->pattern;
260                         len = strlen(s);
261                         if (len == pat_len - (cp - rule->pattern) && memcmp(s, cp, len) == 0) {
262                                 free_filter(rule);
263                                 return;
264                         }
265                 }
266
267                 if (!(lp = new_array(filter_rule_list, 1)))
268                         out_of_memory("add_rule");
269                 lp->head = lp->tail = lp->parent_dirscan_head = NULL;
270                 if (asprintf(&lp->debug_type, " [per-dir %s]", cp) < 0)
271                         out_of_memory("add_rule");
272                 rule->u.mergelist = lp;
273
274                 if (mergelist_cnt == mergelist_size) {
275                         mergelist_size += 5;
276                         mergelist_parents = realloc_array(mergelist_parents,
277                                                 filter_rule *,
278                                                 mergelist_size);
279                         if (!mergelist_parents)
280                                 out_of_memory("add_rule");
281                 }
282                 if (DEBUG_GTE(FILTER, 2)) {
283                         rprintf(FINFO, "[%s] activating mergelist #%d%s\n",
284                                 who_am_i(), mergelist_cnt, lp->debug_type);
285                 }
286                 mergelist_parents[mergelist_cnt++] = rule;
287         } else
288                 rule->u.slash_cnt = slash_cnt;
289
290         if (!listp->tail) {
291                 rule->next = listp->head;
292                 listp->head = listp->tail = rule;
293         } else {
294                 rule->next = listp->tail->next;
295                 listp->tail->next = rule;
296                 listp->tail = rule;
297         }
298 }
299
300 static void clear_filter_list(filter_rule_list *listp)
301 {
302         if (listp->tail) {
303                 /* Truncate any inherited items from the local list. */
304                 listp->tail->next = NULL;
305                 /* Now free everything that is left. */
306                 free_filters(listp->head);
307         }
308
309         listp->head = listp->tail = NULL;
310 }
311
312 /* This returns an expanded (absolute) filename for the merge-file name if
313  * the name has any slashes in it OR if the parent_dirscan var is True;
314  * otherwise it returns the original merge_file name.  If the len_ptr value
315  * is non-NULL the merge_file name is limited by the referenced length
316  * value and will be updated with the length of the resulting name.  We
317  * always return a name that is null terminated, even if the merge_file
318  * name was not. */
319 static char *parse_merge_name(const char *merge_file, unsigned int *len_ptr,
320                               unsigned int prefix_skip)
321 {
322         static char buf[MAXPATHLEN];
323         char *fn, tmpbuf[MAXPATHLEN];
324         unsigned int fn_len;
325
326         if (!parent_dirscan && *merge_file != '/') {
327                 /* Return the name unchanged it doesn't have any slashes. */
328                 if (len_ptr) {
329                         const char *p = merge_file + *len_ptr;
330                         while (--p > merge_file && *p != '/') {}
331                         if (p == merge_file) {
332                                 strlcpy(buf, merge_file, *len_ptr + 1);
333                                 return buf;
334                         }
335                 } else if (strchr(merge_file, '/') == NULL)
336                         return (char *)merge_file;
337         }
338
339         fn = *merge_file == '/' ? buf : tmpbuf;
340         if (sanitize_paths) {
341                 const char *r = prefix_skip ? "/" : NULL;
342                 /* null-terminate the name if it isn't already */
343                 if (len_ptr && merge_file[*len_ptr]) {
344                         char *to = fn == buf ? tmpbuf : buf;
345                         strlcpy(to, merge_file, *len_ptr + 1);
346                         merge_file = to;
347                 }
348                 if (!sanitize_path(fn, merge_file, r, dirbuf_depth, SP_DEFAULT)) {
349                         rprintf(FERROR, "merge-file name overflows: %s\n",
350                                 merge_file);
351                         return NULL;
352                 }
353                 fn_len = strlen(fn);
354         } else {
355                 strlcpy(fn, merge_file, len_ptr ? *len_ptr + 1 : MAXPATHLEN);
356                 fn_len = clean_fname(fn, CFN_COLLAPSE_DOT_DOT_DIRS);
357         }
358
359         /* If the name isn't in buf yet, it's wasn't absolute. */
360         if (fn != buf) {
361                 int d_len = dirbuf_len - prefix_skip;
362                 if (d_len + fn_len >= MAXPATHLEN) {
363                         rprintf(FERROR, "merge-file name overflows: %s\n", fn);
364                         return NULL;
365                 }
366                 memcpy(buf, dirbuf + prefix_skip, d_len);
367                 memcpy(buf + d_len, fn, fn_len + 1);
368                 fn_len = clean_fname(buf, CFN_COLLAPSE_DOT_DOT_DIRS);
369         }
370
371         if (len_ptr)
372                 *len_ptr = fn_len;
373         return buf;
374 }
375
376 /* Sets the dirbuf and dirbuf_len values. */
377 void set_filter_dir(const char *dir, unsigned int dirlen)
378 {
379         unsigned int len;
380         if (*dir != '/') {
381                 memcpy(dirbuf, curr_dir, curr_dir_len);
382                 dirbuf[curr_dir_len] = '/';
383                 len = curr_dir_len + 1;
384                 if (len + dirlen >= MAXPATHLEN)
385                         dirlen = 0;
386         } else
387                 len = 0;
388         memcpy(dirbuf + len, dir, dirlen);
389         dirbuf[dirlen + len] = '\0';
390         dirbuf_len = clean_fname(dirbuf, CFN_COLLAPSE_DOT_DOT_DIRS);
391         if (dirbuf_len > 1 && dirbuf[dirbuf_len-1] == '.'
392             && dirbuf[dirbuf_len-2] == '/')
393                 dirbuf_len -= 2;
394         if (dirbuf_len != 1)
395                 dirbuf[dirbuf_len++] = '/';
396         dirbuf[dirbuf_len] = '\0';
397         if (sanitize_paths)
398                 dirbuf_depth = count_dir_elements(dirbuf + module_dirlen);
399 }
400
401 /* This routine takes a per-dir merge-file entry and finishes its setup.
402  * If the name has a path portion then we check to see if it refers to a
403  * parent directory of the first transfer dir.  If it does, we scan all the
404  * dirs from that point through the parent dir of the transfer dir looking
405  * for the per-dir merge-file in each one. */
406 static BOOL setup_merge_file(int mergelist_num, filter_rule *ex,
407                              filter_rule_list *lp)
408 {
409         char buf[MAXPATHLEN];
410         char *x, *y, *pat = ex->pattern;
411         unsigned int len;
412
413         if (!(x = parse_merge_name(pat, NULL, 0)) || *x != '/')
414                 return 0;
415
416         if (DEBUG_GTE(FILTER, 2)) {
417                 rprintf(FINFO, "[%s] performing parent_dirscan for mergelist #%d%s\n",
418                         who_am_i(), mergelist_num, lp->debug_type);
419         }
420         y = strrchr(x, '/');
421         *y = '\0';
422         ex->pattern = strdup(y+1);
423         if (!*x)
424                 x = "/";
425         if (*x == '/')
426                 strlcpy(buf, x, MAXPATHLEN);
427         else
428                 pathjoin(buf, MAXPATHLEN, dirbuf, x);
429
430         len = clean_fname(buf, CFN_COLLAPSE_DOT_DOT_DIRS);
431         if (len != 1 && len < MAXPATHLEN-1) {
432                 buf[len++] = '/';
433                 buf[len] = '\0';
434         }
435         /* This ensures that the specified dir is a parent of the transfer. */
436         for (x = buf, y = dirbuf; *x && *x == *y; x++, y++) {}
437         if (*x)
438                 y += strlen(y); /* nope -- skip the scan */
439
440         parent_dirscan = True;
441         while (*y) {
442                 char save[MAXPATHLEN];
443                 strlcpy(save, y, MAXPATHLEN);
444                 *y = '\0';
445                 dirbuf_len = y - dirbuf;
446                 strlcpy(x, ex->pattern, MAXPATHLEN - (x - buf));
447                 parse_filter_file(lp, buf, ex, XFLG_ANCHORED2ABS);
448                 if (ex->rflags & FILTRULE_NO_INHERIT) {
449                         /* Free the undesired rules to clean up any per-dir
450                          * mergelists they defined.  Otherwise pop_local_filters
451                          * may crash trying to restore nonexistent state for
452                          * those mergelists. */
453                         free_filters(lp->head);
454                         lp->head = NULL;
455                 }
456                 lp->tail = NULL;
457                 strlcpy(y, save, MAXPATHLEN);
458                 while ((*x++ = *y++) != '/') {}
459         }
460         /* Save current head for freeing when the mergelist becomes inactive. */
461         lp->parent_dirscan_head = lp->head;
462         parent_dirscan = False;
463         if (DEBUG_GTE(FILTER, 2)) {
464                 rprintf(FINFO, "[%s] completed parent_dirscan for mergelist #%d%s\n",
465                         who_am_i(), mergelist_num, lp->debug_type);
466         }
467         free(pat);
468         return 1;
469 }
470
471 struct local_filter_state {
472         int mergelist_cnt;
473         filter_rule_list mergelists[1];
474 };
475
476 /* Each time rsync changes to a new directory it call this function to
477  * handle all the per-dir merge-files.  The "dir" value is the current path
478  * relative to curr_dir (which might not be null-terminated).  We copy it
479  * into dirbuf so that we can easily append a file name on the end. */
480 void *push_local_filters(const char *dir, unsigned int dirlen)
481 {
482         struct local_filter_state *push;
483         int i;
484
485         set_filter_dir(dir, dirlen);
486         if (DEBUG_GTE(FILTER, 2)) {
487                 rprintf(FINFO, "[%s] pushing local filters for %s\n",
488                         who_am_i(), dirbuf);
489         }
490
491         if (!mergelist_cnt) {
492                 /* No old state to save and no new merge files to push. */
493                 return NULL;
494         }
495
496         push = (struct local_filter_state *)new_array(char,
497                           sizeof (struct local_filter_state)
498                         + (mergelist_cnt-1) * sizeof (filter_rule_list));
499         if (!push)
500                 out_of_memory("push_local_filters");
501
502         push->mergelist_cnt = mergelist_cnt;
503         for (i = 0; i < mergelist_cnt; i++) {
504                 memcpy(&push->mergelists[i], mergelist_parents[i]->u.mergelist,
505                        sizeof (filter_rule_list));
506         }
507
508         /* Note: parse_filter_file() might increase mergelist_cnt, so keep
509          * this loop separate from the above loop. */
510         for (i = 0; i < mergelist_cnt; i++) {
511                 filter_rule *ex = mergelist_parents[i];
512                 filter_rule_list *lp = ex->u.mergelist;
513
514                 if (DEBUG_GTE(FILTER, 2)) {
515                         rprintf(FINFO, "[%s] pushing mergelist #%d%s\n",
516                                 who_am_i(), i, lp->debug_type);
517                 }
518
519                 lp->tail = NULL; /* Switch any local rules to inherited. */
520                 if (ex->rflags & FILTRULE_NO_INHERIT)
521                         lp->head = NULL;
522
523                 if (ex->rflags & FILTRULE_FINISH_SETUP) {
524                         ex->rflags &= ~FILTRULE_FINISH_SETUP;
525                         if (setup_merge_file(i, ex, lp))
526                                 set_filter_dir(dir, dirlen);
527                 }
528
529                 if (strlcpy(dirbuf + dirbuf_len, ex->pattern,
530                     MAXPATHLEN - dirbuf_len) < MAXPATHLEN - dirbuf_len) {
531                         parse_filter_file(lp, dirbuf, ex,
532                                           XFLG_ANCHORED2ABS);
533                 } else {
534                         io_error |= IOERR_GENERAL;
535                         rprintf(FERROR,
536                             "cannot add local filter rules in long-named directory: %s\n",
537                             full_fname(dirbuf));
538                 }
539                 dirbuf[dirbuf_len] = '\0';
540         }
541
542         return (void*)push;
543 }
544
545 void pop_local_filters(void *mem)
546 {
547         struct local_filter_state *pop = (struct local_filter_state *)mem;
548         int i;
549         int old_mergelist_cnt = pop ? pop->mergelist_cnt : 0;
550
551         if (DEBUG_GTE(FILTER, 2))
552                 rprintf(FINFO, "[%s] popping local filters\n", who_am_i());
553
554         for (i = mergelist_cnt; i-- > 0; ) {
555                 filter_rule *ex = mergelist_parents[i];
556                 filter_rule_list *lp = ex->u.mergelist;
557
558                 if (DEBUG_GTE(FILTER, 2)) {
559                         rprintf(FINFO, "[%s] popping mergelist #%d%s\n",
560                                 who_am_i(), i, lp->debug_type);
561                 }
562
563                 clear_filter_list(lp);
564
565                 if (i >= old_mergelist_cnt) {
566                         /* This mergelist does not exist in the state to be
567                          * restored.  Free its parent_dirscan list to clean up
568                          * any per-dir mergelists defined there so we don't
569                          * crash trying to restore nonexistent state for them
570                          * below.  (Counterpart to setup_merge_file call in
571                          * push_local_filters.  Must be done here, not in
572                          * free_filter, for LIFO order.) */
573                         if (DEBUG_GTE(FILTER, 2)) {
574                                 rprintf(FINFO, "[%s] freeing parent_dirscan filters of mergelist #%d%s\n",
575                                         who_am_i(), i, ex->u.mergelist->debug_type);
576                         }
577                         free_filters(lp->parent_dirscan_head);
578                         lp->parent_dirscan_head = NULL;
579                 }
580         }
581
582         /* If we cleaned things up properly, the only still-active mergelists
583          * should be those with a state to be restored. */
584         assert(mergelist_cnt == old_mergelist_cnt);
585
586         if (!pop) {
587                 /* No state to restore. */
588                 return;
589         }
590
591         for (i = 0; i < mergelist_cnt; i++) {
592                 memcpy(mergelist_parents[i]->u.mergelist, &pop->mergelists[i],
593                        sizeof (filter_rule_list));
594         }
595
596         free(pop);
597 }
598
599 void change_local_filter_dir(const char *dname, int dlen, int dir_depth)
600 {
601         static int cur_depth = -1;
602         static void *filt_array[MAXPATHLEN/2+1];
603
604         if (!dname) {
605                 for ( ; cur_depth >= 0; cur_depth--) {
606                         if (filt_array[cur_depth]) {
607                                 pop_local_filters(filt_array[cur_depth]);
608                                 filt_array[cur_depth] = NULL;
609                         }
610                 }
611                 return;
612         }
613
614         assert(dir_depth < MAXPATHLEN/2+1);
615
616         for ( ; cur_depth >= dir_depth; cur_depth--) {
617                 if (filt_array[cur_depth]) {
618                         pop_local_filters(filt_array[cur_depth]);
619                         filt_array[cur_depth] = NULL;
620                 }
621         }
622
623         cur_depth = dir_depth;
624         filt_array[cur_depth] = push_local_filters(dname, dlen);
625 }
626
627 static int rule_matches(const char *fname, filter_rule *ex, int name_is_dir)
628 {
629         int slash_handling, str_cnt = 0, anchored_match = 0;
630         int ret_match = ex->rflags & FILTRULE_NEGATE ? 0 : 1;
631         char *p, *pattern = ex->pattern;
632         const char *strings[16]; /* more than enough */
633         const char *name = fname + (*fname == '/');
634
635         if (!*name)
636                 return 0;
637
638         if (!ex->u.slash_cnt && !(ex->rflags & FILTRULE_WILD2)) {
639                 /* If the pattern does not have any slashes AND it does
640                  * not have a "**" (which could match a slash), then we
641                  * just match the name portion of the path. */
642                 if ((p = strrchr(name,'/')) != NULL)
643                         name = p+1;
644         } else if (ex->rflags & FILTRULE_ABS_PATH && *fname != '/'
645             && curr_dir_len > module_dirlen + 1) {
646                 /* If we're matching against an absolute-path pattern,
647                  * we need to prepend our full path info. */
648                 strings[str_cnt++] = curr_dir + module_dirlen + 1;
649                 strings[str_cnt++] = "/";
650         } else if (ex->rflags & FILTRULE_WILD2_PREFIX && *fname != '/') {
651                 /* Allow "**"+"/" to match at the start of the string. */
652                 strings[str_cnt++] = "/";
653         }
654         strings[str_cnt++] = name;
655         if (name_is_dir) {
656                 /* Allow a trailing "/"+"***" to match the directory. */
657                 if (ex->rflags & FILTRULE_WILD3_SUFFIX)
658                         strings[str_cnt++] = "/";
659         } else if (ex->rflags & FILTRULE_DIRECTORY)
660                 return !ret_match;
661         strings[str_cnt] = NULL;
662
663         if (*pattern == '/') {
664                 anchored_match = 1;
665                 pattern++;
666         }
667
668         if (!anchored_match && ex->u.slash_cnt
669             && !(ex->rflags & FILTRULE_WILD2)) {
670                 /* A non-anchored match with an infix slash and no "**"
671                  * needs to match the last slash_cnt+1 name elements. */
672                 slash_handling = ex->u.slash_cnt + 1;
673         } else if (!anchored_match && !(ex->rflags & FILTRULE_WILD2_PREFIX)
674                                    && ex->rflags & FILTRULE_WILD2) {
675                 /* A non-anchored match with an infix or trailing "**" (but not
676                  * a prefixed "**") needs to try matching after every slash. */
677                 slash_handling = -1;
678         } else {
679                 /* The pattern matches only at the start of the path or name. */
680                 slash_handling = 0;
681         }
682
683         if (ex->rflags & FILTRULE_WILD) {
684                 if (wildmatch_array(pattern, strings, slash_handling))
685                         return ret_match;
686         } else if (str_cnt > 1) {
687                 if (litmatch_array(pattern, strings, slash_handling))
688                         return ret_match;
689         } else if (anchored_match) {
690                 if (strcmp(name, pattern) == 0)
691                         return ret_match;
692         } else {
693                 int l1 = strlen(name);
694                 int l2 = strlen(pattern);
695                 if (l2 <= l1 &&
696                     strcmp(name+(l1-l2),pattern) == 0 &&
697                     (l1==l2 || name[l1-(l2+1)] == '/')) {
698                         return ret_match;
699                 }
700         }
701
702         return !ret_match;
703 }
704
705 static void report_filter_result(enum logcode code, char const *name,
706                                  filter_rule const *ent,
707                                  int name_is_dir, const char *type)
708 {
709         /* If a trailing slash is present to match only directories,
710          * then it is stripped out by add_rule().  So as a special
711          * case we add it back in here. */
712
713         if (DEBUG_GTE(FILTER, 1)) {
714                 static char *actions[2][2]
715                     = { {"show", "hid"}, {"risk", "protect"} };
716                 const char *w = who_am_i();
717                 rprintf(code, "[%s] %sing %s %s because of pattern %s%s%s\n",
718                     w, actions[*w!='s'][!(ent->rflags & FILTRULE_INCLUDE)],
719                     name_is_dir ? "directory" : "file", name, ent->pattern,
720                     ent->rflags & FILTRULE_DIRECTORY ? "/" : "", type);
721         }
722 }
723
724 /* Return -1 if file "name" is defined to be excluded by the specified
725  * exclude list, 1 if it is included, and 0 if it was not matched. */
726 int check_filter(filter_rule_list *listp, enum logcode code,
727                  const char *name, int name_is_dir)
728 {
729         filter_rule *ent;
730
731         for (ent = listp->head; ent; ent = ent->next) {
732                 if (ignore_perishable && ent->rflags & FILTRULE_PERISHABLE)
733                         continue;
734                 if (ent->rflags & FILTRULE_PERDIR_MERGE) {
735                         int rc = check_filter(ent->u.mergelist, code, name,
736                                               name_is_dir);
737                         if (rc)
738                                 return rc;
739                         continue;
740                 }
741                 if (ent->rflags & FILTRULE_CVS_IGNORE) {
742                         int rc = check_filter(&cvs_filter_list, code, name,
743                                               name_is_dir);
744                         if (rc)
745                                 return rc;
746                         continue;
747                 }
748                 if (rule_matches(name, ent, name_is_dir)) {
749                         report_filter_result(code, name, ent, name_is_dir,
750                                              listp->debug_type);
751                         return ent->rflags & FILTRULE_INCLUDE ? 1 : -1;
752                 }
753         }
754
755         return 0;
756 }
757
758 #define RULE_STRCMP(s,r) rule_strcmp((s), (r), sizeof (r) - 1)
759
760 static const uchar *rule_strcmp(const uchar *str, const char *rule, int rule_len)
761 {
762         if (strncmp((char*)str, rule, rule_len) != 0)
763                 return NULL;
764         if (isspace(str[rule_len]) || str[rule_len] == '_' || !str[rule_len])
765                 return str + rule_len - 1;
766         if (str[rule_len] == ',')
767                 return str + rule_len;
768         return NULL;
769 }
770
771 #define FILTRULES_FROM_CONTAINER (FILTRULE_ABS_PATH | FILTRULE_INCLUDE \
772                                 | FILTRULE_DIRECTORY | FILTRULE_NEGATE \
773                                 | FILTRULE_PERISHABLE)
774
775 /* Gets the next include/exclude rule from *rulestr_ptr and advances
776  * *rulestr_ptr to point beyond it.  Stores the pattern's start (within
777  * *rulestr_ptr) and length in *pat_ptr and *pat_len_ptr, and returns a newly
778  * allocated filter_rule containing the rest of the information.  Returns
779  * NULL if there are no more rules in the input.
780  *
781  * The template provides defaults for the new rule to inherit, and the
782  * template rflags and the xflags additionally affect parsing. */
783 static filter_rule *parse_rule_tok(const char **rulestr_ptr,
784                                    const filter_rule *template, int xflags,
785                                    const char **pat_ptr, unsigned int *pat_len_ptr)
786 {
787         const uchar *s = (const uchar *)*rulestr_ptr;
788         filter_rule *rule;
789         unsigned int len;
790
791         if (template->rflags & FILTRULE_WORD_SPLIT) {
792                 /* Skip over any initial whitespace. */
793                 while (isspace(*s))
794                         s++;
795                 /* Update to point to real start of rule. */
796                 *rulestr_ptr = (const char *)s;
797         }
798         if (!*s)
799                 return NULL;
800
801         if (!(rule = new0(filter_rule)))
802                 out_of_memory("parse_rule_tok");
803
804         /* Inherit from the template.  Don't inherit FILTRULES_SIDES; we check
805          * that later. */
806         rule->rflags = template->rflags & FILTRULES_FROM_CONTAINER;
807
808         /* Figure out what kind of a filter rule "s" is pointing at.  Note
809          * that if FILTRULE_NO_PREFIXES is set, the rule is either an include
810          * or an exclude based on the inheritance of the FILTRULE_INCLUDE
811          * flag (above).  XFLG_OLD_PREFIXES indicates a compatibility mode
812          * for old include/exclude patterns where just "+ " and "- " are
813          * allowed as optional prefixes.  */
814         if (template->rflags & FILTRULE_NO_PREFIXES) {
815                 if (*s == '!' && template->rflags & FILTRULE_CVS_IGNORE)
816                         rule->rflags |= FILTRULE_CLEAR_LIST; /* Tentative! */
817         } else if (xflags & XFLG_OLD_PREFIXES) {
818                 if (*s == '-' && s[1] == ' ') {
819                         rule->rflags &= ~FILTRULE_INCLUDE;
820                         s += 2;
821                 } else if (*s == '+' && s[1] == ' ') {
822                         rule->rflags |= FILTRULE_INCLUDE;
823                         s += 2;
824                 } else if (*s == '!')
825                         rule->rflags |= FILTRULE_CLEAR_LIST; /* Tentative! */
826         } else {
827                 char ch = 0;
828                 BOOL prefix_specifies_side = False;
829                 switch (*s) {
830                 case 'c':
831                         if ((s = RULE_STRCMP(s, "clear")) != NULL)
832                                 ch = '!';
833                         break;
834                 case 'd':
835                         if ((s = RULE_STRCMP(s, "dir-merge")) != NULL)
836                                 ch = ':';
837                         break;
838                 case 'e':
839                         if ((s = RULE_STRCMP(s, "exclude")) != NULL)
840                                 ch = '-';
841                         break;
842                 case 'h':
843                         if ((s = RULE_STRCMP(s, "hide")) != NULL)
844                                 ch = 'H';
845                         break;
846                 case 'i':
847                         if ((s = RULE_STRCMP(s, "include")) != NULL)
848                                 ch = '+';
849                         break;
850                 case 'm':
851                         if ((s = RULE_STRCMP(s, "merge")) != NULL)
852                                 ch = '.';
853                         break;
854                 case 'p':
855                         if ((s = RULE_STRCMP(s, "protect")) != NULL)
856                                 ch = 'P';
857                         break;
858                 case 'r':
859                         if ((s = RULE_STRCMP(s, "risk")) != NULL)
860                                 ch = 'R';
861                         break;
862                 case 's':
863                         if ((s = RULE_STRCMP(s, "show")) != NULL)
864                                 ch = 'S';
865                         break;
866                 default:
867                         ch = *s;
868                         if (s[1] == ',')
869                                 s++;
870                         break;
871                 }
872                 switch (ch) {
873                 case ':':
874                         rule->rflags |= FILTRULE_PERDIR_MERGE
875                                        | FILTRULE_FINISH_SETUP;
876                         /* FALL THROUGH */
877                 case '.':
878                         rule->rflags |= FILTRULE_MERGE_FILE;
879                         break;
880                 case '+':
881                         rule->rflags |= FILTRULE_INCLUDE;
882                         break;
883                 case '-':
884                         break;
885                 case 'S':
886                         rule->rflags |= FILTRULE_INCLUDE;
887                         /* FALL THROUGH */
888                 case 'H':
889                         rule->rflags |= FILTRULE_SENDER_SIDE;
890                         prefix_specifies_side = True;
891                         break;
892                 case 'R':
893                         rule->rflags |= FILTRULE_INCLUDE;
894                         /* FALL THROUGH */
895                 case 'P':
896                         rule->rflags |= FILTRULE_RECEIVER_SIDE;
897                         prefix_specifies_side = True;
898                         break;
899                 case '!':
900                         rule->rflags |= FILTRULE_CLEAR_LIST;
901                         break;
902                 default:
903                         rprintf(FERROR, "Unknown filter rule: `%s'\n", *rulestr_ptr);
904                         exit_cleanup(RERR_SYNTAX);
905                 }
906                 while (ch != '!' && *++s && *s != ' ' && *s != '_') {
907                         if (template->rflags & FILTRULE_WORD_SPLIT && isspace(*s)) {
908                                 s--;
909                                 break;
910                         }
911                         switch (*s) {
912                         default:
913                             invalid:
914                                 rprintf(FERROR,
915                                         "invalid modifier '%c' at position %d in filter rule: %s\n",
916                                         *s, (int)(s - (const uchar *)*rulestr_ptr), *rulestr_ptr);
917                                 exit_cleanup(RERR_SYNTAX);
918                         case '-':
919                                 if (!BITS_SETnUNSET(rule->rflags, FILTRULE_MERGE_FILE, FILTRULE_NO_PREFIXES))
920                                         goto invalid;
921                                 rule->rflags |= FILTRULE_NO_PREFIXES;
922                                 break;
923                         case '+':
924                                 if (!BITS_SETnUNSET(rule->rflags, FILTRULE_MERGE_FILE, FILTRULE_NO_PREFIXES))
925                                         goto invalid;
926                                 rule->rflags |= FILTRULE_NO_PREFIXES
927                                               | FILTRULE_INCLUDE;
928                                 break;
929                         case '/':
930                                 rule->rflags |= FILTRULE_ABS_PATH;
931                                 break;
932                         case '!':
933                                 /* Negation really goes with the pattern, so it
934                                  * isn't useful as a merge-file default. */
935                                 if (rule->rflags & FILTRULE_MERGE_FILE)
936                                         goto invalid;
937                                 rule->rflags |= FILTRULE_NEGATE;
938                                 break;
939                         case 'C':
940                                 if (rule->rflags & FILTRULE_NO_PREFIXES || prefix_specifies_side)
941                                         goto invalid;
942                                 rule->rflags |= FILTRULE_NO_PREFIXES
943                                               | FILTRULE_WORD_SPLIT
944                                               | FILTRULE_NO_INHERIT
945                                               | FILTRULE_CVS_IGNORE;
946                                 break;
947                         case 'e':
948                                 if (!(rule->rflags & FILTRULE_MERGE_FILE))
949                                         goto invalid;
950                                 rule->rflags |= FILTRULE_EXCLUDE_SELF;
951                                 break;
952                         case 'n':
953                                 if (!(rule->rflags & FILTRULE_MERGE_FILE))
954                                         goto invalid;
955                                 rule->rflags |= FILTRULE_NO_INHERIT;
956                                 break;
957                         case 'p':
958                                 rule->rflags |= FILTRULE_PERISHABLE;
959                                 break;
960                         case 'r':
961                                 if (prefix_specifies_side)
962                                         goto invalid;
963                                 rule->rflags |= FILTRULE_RECEIVER_SIDE;
964                                 break;
965                         case 's':
966                                 if (prefix_specifies_side)
967                                         goto invalid;
968                                 rule->rflags |= FILTRULE_SENDER_SIDE;
969                                 break;
970                         case 'w':
971                                 if (!(rule->rflags & FILTRULE_MERGE_FILE))
972                                         goto invalid;
973                                 rule->rflags |= FILTRULE_WORD_SPLIT;
974                                 break;
975                         }
976                 }
977                 if (*s)
978                         s++;
979         }
980         if (template->rflags & FILTRULES_SIDES) {
981                 if (rule->rflags & FILTRULES_SIDES) {
982                         /* The filter and template both specify side(s).  This
983                          * is dodgy (and won't work correctly if the template is
984                          * a one-sided per-dir merge rule), so reject it. */
985                         rprintf(FERROR,
986                                 "specified-side merge file contains specified-side filter: %s\n",
987                                 *rulestr_ptr);
988                         exit_cleanup(RERR_SYNTAX);
989                 }
990                 rule->rflags |= template->rflags & FILTRULES_SIDES;
991         }
992
993         if (template->rflags & FILTRULE_WORD_SPLIT) {
994                 const uchar *cp = s;
995                 /* Token ends at whitespace or the end of the string. */
996                 while (!isspace(*cp) && *cp != '\0')
997                         cp++;
998                 len = cp - s;
999         } else
1000                 len = strlen((char*)s);
1001
1002         if (rule->rflags & FILTRULE_CLEAR_LIST) {
1003                 if (!(rule->rflags & FILTRULE_NO_PREFIXES)
1004                  && !(xflags & XFLG_OLD_PREFIXES) && len) {
1005                         rprintf(FERROR,
1006                                 "'!' rule has trailing characters: %s\n", *rulestr_ptr);
1007                         exit_cleanup(RERR_SYNTAX);
1008                 }
1009                 if (len > 1)
1010                         rule->rflags &= ~FILTRULE_CLEAR_LIST;
1011         } else if (!len && !(rule->rflags & FILTRULE_CVS_IGNORE)) {
1012                 rprintf(FERROR, "unexpected end of filter rule: %s\n", *rulestr_ptr);
1013                 exit_cleanup(RERR_SYNTAX);
1014         }
1015
1016         /* --delete-excluded turns an un-modified include/exclude into a
1017          * sender-side rule.  We also affect per-dir merge files that take
1018          * no prefixes as a simple optimization. */
1019         if (delete_excluded
1020          && !(rule->rflags & FILTRULES_SIDES)
1021          && (!(rule->rflags & FILTRULE_PERDIR_MERGE)
1022           || rule->rflags & FILTRULE_NO_PREFIXES))
1023                 rule->rflags |= FILTRULE_SENDER_SIDE;
1024
1025         *pat_ptr = (const char *)s;
1026         *pat_len_ptr = len;
1027         *rulestr_ptr = *pat_ptr + len;
1028         return rule;
1029 }
1030
1031 static char default_cvsignore[] =
1032         /* These default ignored items come from the CVS manual. */
1033         "RCS SCCS CVS CVS.adm RCSLOG cvslog.* tags TAGS"
1034         " .make.state .nse_depinfo *~ #* .#* ,* _$* *$"
1035         " *.old *.bak *.BAK *.orig *.rej .del-*"
1036         " *.a *.olb *.o *.obj *.so *.exe"
1037         " *.Z *.elc *.ln core"
1038         /* The rest we added to suit ourself. */
1039         " .svn/ .git/ .hg/ .bzr/";
1040
1041 static void get_cvs_excludes(uint32 rflags)
1042 {
1043         static int initialized = 0;
1044         char *p, fname[MAXPATHLEN];
1045
1046         if (initialized)
1047                 return;
1048         initialized = 1;
1049
1050         parse_filter_str(&cvs_filter_list, default_cvsignore,
1051                          rule_template(rflags | (protocol_version >= 30 ? FILTRULE_PERISHABLE : 0)),
1052                          0);
1053
1054         p = module_id >= 0 && lp_use_chroot(module_id) ? "/" : getenv("HOME");
1055         if (p && pathjoin(fname, MAXPATHLEN, p, ".cvsignore") < MAXPATHLEN)
1056                 parse_filter_file(&cvs_filter_list, fname, rule_template(rflags), 0);
1057
1058         parse_filter_str(&cvs_filter_list, getenv("CVSIGNORE"), rule_template(rflags), 0);
1059 }
1060
1061 const filter_rule *rule_template(uint32 rflags)
1062 {
1063         static filter_rule template; /* zero-initialized */
1064         template.rflags = rflags;
1065         return &template;
1066 }
1067
1068 void parse_filter_str(filter_rule_list *listp, const char *rulestr,
1069                      const filter_rule *template, int xflags)
1070 {
1071         filter_rule *rule;
1072         const char *pat;
1073         unsigned int pat_len;
1074
1075         if (!rulestr)
1076                 return;
1077
1078         while (1) {
1079                 uint32 new_rflags;
1080
1081                 /* Remember that the returned string is NOT '\0' terminated! */
1082                 if (!(rule = parse_rule_tok(&rulestr, template, xflags, &pat, &pat_len)))
1083                         break;
1084
1085                 if (pat_len >= MAXPATHLEN) {
1086                         rprintf(FERROR, "discarding over-long filter: %.*s\n",
1087                                 (int)pat_len, pat);
1088                     free_continue:
1089                         free_filter(rule);
1090                         continue;
1091                 }
1092
1093                 new_rflags = rule->rflags;
1094                 if (new_rflags & FILTRULE_CLEAR_LIST) {
1095                         if (DEBUG_GTE(FILTER, 2)) {
1096                                 rprintf(FINFO,
1097                                         "[%s] clearing filter list%s\n",
1098                                         who_am_i(), listp->debug_type);
1099                         }
1100                         clear_filter_list(listp);
1101                         goto free_continue;
1102                 }
1103
1104                 if (new_rflags & FILTRULE_MERGE_FILE) {
1105                         if (!pat_len) {
1106                                 pat = ".cvsignore";
1107                                 pat_len = 10;
1108                         }
1109                         if (new_rflags & FILTRULE_EXCLUDE_SELF) {
1110                                 const char *name;
1111                                 filter_rule *excl_self;
1112
1113                                 if (!(excl_self = new0(filter_rule)))
1114                                         out_of_memory("parse_filter_str");
1115                                 /* Find the beginning of the basename and add an exclude for it. */
1116                                 for (name = pat + pat_len; name > pat && name[-1] != '/'; name--) {}
1117                                 add_rule(listp, name, (pat + pat_len) - name, excl_self, 0);
1118                                 rule->rflags &= ~FILTRULE_EXCLUDE_SELF;
1119                         }
1120                         if (new_rflags & FILTRULE_PERDIR_MERGE) {
1121                                 if (parent_dirscan) {
1122                                         const char *p;
1123                                         unsigned int len = pat_len;
1124                                         if ((p = parse_merge_name(pat, &len, module_dirlen)))
1125                                                 add_rule(listp, p, len, rule, 0);
1126                                         else
1127                                                 free_filter(rule);
1128                                         continue;
1129                                 }
1130                         } else {
1131                                 const char *p;
1132                                 unsigned int len = pat_len;
1133                                 if ((p = parse_merge_name(pat, &len, 0)))
1134                                         parse_filter_file(listp, p, rule, XFLG_FATAL_ERRORS);
1135                                 free_filter(rule);
1136                                 continue;
1137                         }
1138                 }
1139
1140                 add_rule(listp, pat, pat_len, rule, xflags);
1141
1142                 if (new_rflags & FILTRULE_CVS_IGNORE
1143                     && !(new_rflags & FILTRULE_MERGE_FILE))
1144                         get_cvs_excludes(new_rflags);
1145         }
1146 }
1147
1148 void parse_filter_file(filter_rule_list *listp, const char *fname, const filter_rule *template, int xflags)
1149 {
1150         FILE *fp;
1151         char line[BIGPATHBUFLEN];
1152         char *eob = line + sizeof line - 1;
1153         BOOL word_split = (template->rflags & FILTRULE_WORD_SPLIT) != 0;
1154
1155         if (!fname || !*fname)
1156                 return;
1157
1158         if (*fname != '-' || fname[1] || am_server) {
1159                 if (daemon_filter_list.head) {
1160                         strlcpy(line, fname, sizeof line);
1161                         clean_fname(line, CFN_COLLAPSE_DOT_DOT_DIRS);
1162                         if (check_filter(&daemon_filter_list, FLOG, line, 0) < 0)
1163                                 fp = NULL;
1164                         else
1165                                 fp = fopen(line, "rb");
1166                 } else
1167                         fp = fopen(fname, "rb");
1168         } else
1169                 fp = stdin;
1170
1171         if (DEBUG_GTE(FILTER, 2)) {
1172                 rprintf(FINFO, "[%s] parse_filter_file(%s,%x,%x)%s\n",
1173                         who_am_i(), fname, template->rflags, xflags,
1174                         fp ? "" : " [not found]");
1175         }
1176
1177         if (!fp) {
1178                 if (xflags & XFLG_FATAL_ERRORS) {
1179                         rsyserr(FERROR, errno,
1180                                 "failed to open %sclude file %s",
1181                                 template->rflags & FILTRULE_INCLUDE ? "in" : "ex",
1182                                 fname);
1183                         exit_cleanup(RERR_FILEIO);
1184                 }
1185                 return;
1186         }
1187         dirbuf[dirbuf_len] = '\0';
1188
1189         while (1) {
1190                 char *s = line;
1191                 int ch, overflow = 0;
1192                 while (1) {
1193                         if ((ch = getc(fp)) == EOF) {
1194                                 if (ferror(fp) && errno == EINTR) {
1195                                         clearerr(fp);
1196                                         continue;
1197                                 }
1198                                 break;
1199                         }
1200                         if (word_split && isspace(ch))
1201                                 break;
1202                         if (eol_nulls? !ch : (ch == '\n' || ch == '\r'))
1203                                 break;
1204                         if (s < eob)
1205                                 *s++ = ch;
1206                         else
1207                                 overflow = 1;
1208                 }
1209                 if (overflow) {
1210                         rprintf(FERROR, "discarding over-long filter: %s...\n", line);
1211                         s = line;
1212                 }
1213                 *s = '\0';
1214                 /* Skip an empty token and (when line parsing) comments. */
1215                 if (*line && (word_split || (*line != ';' && *line != '#')))
1216                         parse_filter_str(listp, line, template, xflags);
1217                 if (ch == EOF)
1218                         break;
1219         }
1220         fclose(fp);
1221 }
1222
1223 /* If the "for_xfer" flag is set, the prefix is made compatible with the
1224  * current protocol_version (if possible) or a NULL is returned (if not
1225  * possible). */
1226 char *get_rule_prefix(filter_rule *rule, const char *pat, int for_xfer,
1227                       unsigned int *plen_ptr)
1228 {
1229         static char buf[MAX_RULE_PREFIX+1];
1230         char *op = buf;
1231         int legal_len = for_xfer && protocol_version < 29 ? 1 : MAX_RULE_PREFIX-1;
1232
1233         if (rule->rflags & FILTRULE_PERDIR_MERGE) {
1234                 if (legal_len == 1)
1235                         return NULL;
1236                 *op++ = ':';
1237         } else if (rule->rflags & FILTRULE_INCLUDE)
1238                 *op++ = '+';
1239         else if (legal_len != 1
1240             || ((*pat == '-' || *pat == '+') && pat[1] == ' '))
1241                 *op++ = '-';
1242         else
1243                 legal_len = 0;
1244
1245         if (rule->rflags & FILTRULE_ABS_PATH)
1246                 *op++ = '/';
1247         if (rule->rflags & FILTRULE_NEGATE)
1248                 *op++ = '!';
1249         if (rule->rflags & FILTRULE_CVS_IGNORE)
1250                 *op++ = 'C';
1251         else {
1252                 if (rule->rflags & FILTRULE_NO_INHERIT)
1253                         *op++ = 'n';
1254                 if (rule->rflags & FILTRULE_WORD_SPLIT)
1255                         *op++ = 'w';
1256                 if (rule->rflags & FILTRULE_NO_PREFIXES) {
1257                         if (rule->rflags & FILTRULE_INCLUDE)
1258                                 *op++ = '+';
1259                         else
1260                                 *op++ = '-';
1261                 }
1262         }
1263         if (rule->rflags & FILTRULE_EXCLUDE_SELF)
1264                 *op++ = 'e';
1265         if (rule->rflags & FILTRULE_SENDER_SIDE
1266             && (!for_xfer || protocol_version >= 29))
1267                 *op++ = 's';
1268         if (rule->rflags & FILTRULE_RECEIVER_SIDE
1269             && (!for_xfer || protocol_version >= 29
1270              || (delete_excluded && am_sender)))
1271                 *op++ = 'r';
1272         if (rule->rflags & FILTRULE_PERISHABLE) {
1273                 if (!for_xfer || protocol_version >= 30)
1274                         *op++ = 'p';
1275                 else if (am_sender)
1276                         return NULL;
1277         }
1278         if (op - buf > legal_len)
1279                 return NULL;
1280         if (legal_len)
1281                 *op++ = ' ';
1282         *op = '\0';
1283         if (plen_ptr)
1284                 *plen_ptr = op - buf;
1285         return buf;
1286 }
1287
1288 static void send_rules(int f_out, filter_rule_list *flp)
1289 {
1290         filter_rule *ent, *prev = NULL;
1291
1292         for (ent = flp->head; ent; ent = ent->next) {
1293                 unsigned int len, plen, dlen;
1294                 int elide = 0;
1295                 char *p;
1296
1297                 /* Note we need to check delete_excluded here in addition to
1298                  * the code in parse_rule_tok() because some rules may have
1299                  * been added before we found the --delete-excluded option.
1300                  * We must also elide any CVS merge-file rules to avoid a
1301                  * backward compatibility problem, and we elide any no-prefix
1302                  * merge files as an optimization (since they can only have
1303                  * include/exclude rules). */
1304                 if (ent->rflags & FILTRULE_SENDER_SIDE)
1305                         elide = am_sender ? 1 : -1;
1306                 if (ent->rflags & FILTRULE_RECEIVER_SIDE)
1307                         elide = elide ? 0 : am_sender ? -1 : 1;
1308                 else if (delete_excluded && !elide
1309                  && (!(ent->rflags & FILTRULE_PERDIR_MERGE)
1310                   || ent->rflags & FILTRULE_NO_PREFIXES))
1311                         elide = am_sender ? 1 : -1;
1312                 if (elide < 0) {
1313                         if (prev)
1314                                 prev->next = ent->next;
1315                         else
1316                                 flp->head = ent->next;
1317                 } else
1318                         prev = ent;
1319                 if (elide > 0)
1320                         continue;
1321                 if (ent->rflags & FILTRULE_CVS_IGNORE
1322                     && !(ent->rflags & FILTRULE_MERGE_FILE)) {
1323                         int f = am_sender || protocol_version < 29 ? f_out : -2;
1324                         send_rules(f, &cvs_filter_list);
1325                         if (f == f_out)
1326                                 continue;
1327                 }
1328                 p = get_rule_prefix(ent, ent->pattern, 1, &plen);
1329                 if (!p) {
1330                         rprintf(FERROR,
1331                                 "filter rules are too modern for remote rsync.\n");
1332                         exit_cleanup(RERR_PROTOCOL);
1333                 }
1334                 if (f_out < 0)
1335                         continue;
1336                 len = strlen(ent->pattern);
1337                 dlen = ent->rflags & FILTRULE_DIRECTORY ? 1 : 0;
1338                 if (!(plen + len + dlen))
1339                         continue;
1340                 write_int(f_out, plen + len + dlen);
1341                 if (plen)
1342                         write_buf(f_out, p, plen);
1343                 write_buf(f_out, ent->pattern, len);
1344                 if (dlen)
1345                         write_byte(f_out, '/');
1346         }
1347         flp->tail = prev;
1348 }
1349
1350 /* This is only called by the client. */
1351 void send_filter_list(int f_out)
1352 {
1353         int receiver_wants_list = prune_empty_dirs
1354             || (delete_mode && (!delete_excluded || protocol_version >= 29));
1355
1356         if (local_server || (am_sender && !receiver_wants_list))
1357                 f_out = -1;
1358         if (cvs_exclude && am_sender) {
1359                 if (protocol_version >= 29)
1360                         parse_filter_str(&filter_list, ":C", rule_template(0), 0);
1361                 parse_filter_str(&filter_list, "-C", rule_template(0), 0);
1362         }
1363
1364         send_rules(f_out, &filter_list);
1365
1366         if (f_out >= 0)
1367                 write_int(f_out, 0);
1368
1369         if (cvs_exclude) {
1370                 if (!am_sender || protocol_version < 29)
1371                         parse_filter_str(&filter_list, ":C", rule_template(0), 0);
1372                 if (!am_sender)
1373                         parse_filter_str(&filter_list, "-C", rule_template(0), 0);
1374         }
1375 }
1376
1377 /* This is only called by the server. */
1378 void recv_filter_list(int f_in)
1379 {
1380         char line[BIGPATHBUFLEN];
1381         int xflags = protocol_version >= 29 ? 0 : XFLG_OLD_PREFIXES;
1382         int receiver_wants_list = prune_empty_dirs
1383             || (delete_mode
1384              && (!delete_excluded || protocol_version >= 29));
1385         unsigned int len;
1386
1387         if (!local_server && (am_sender || receiver_wants_list)) {
1388                 while ((len = read_int(f_in)) != 0) {
1389                         if (len >= sizeof line)
1390                                 overflow_exit("recv_rules");
1391                         read_sbuf(f_in, line, len);
1392                         parse_filter_str(&filter_list, line, rule_template(0), xflags);
1393                 }
1394         }
1395
1396         if (cvs_exclude) {
1397                 if (local_server || am_sender || protocol_version < 29)
1398                         parse_filter_str(&filter_list, ":C", rule_template(0), 0);
1399                 if (local_server || am_sender)
1400                         parse_filter_str(&filter_list, "-C", rule_template(0), 0);
1401         }
1402
1403         if (local_server) /* filter out any rules that aren't for us. */
1404                 send_rules(-1, &filter_list);
1405 }