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) 2003-2015 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 int saw_xattr_filter = 0;
  48
  49 /* Need room enough for ":MODS " prefix plus some room to grow. */
  50 #define MAX_RULE_PREFIX (16)
  51
  52 #define SLASH_WILD3_SUFFIX "/***"
  53
  54 /* The dirbuf is set by push_local_filters() to the current subdirectory
  55  * relative to curr_dir that is being processed.  The path always has a
  56  * trailing slash appended, and the variable dirbuf_len contains the length
  57  * of this path prefix.  The path is always absolute. */
  58 static char dirbuf[MAXPATHLEN+1];
  59 static unsigned int dirbuf_len = 0;
  60 static int dirbuf_depth;
  61
  62 /* This is True when we're scanning parent dirs for per-dir merge-files. */
  63 static BOOL parent_dirscan = False;
  64
  65 /* This array contains a list of all the currently active per-dir merge
  66  * files.  This makes it easier to save the appropriate values when we
  67  * "push" down into each subdirectory. */
  68 static filter_rule **mergelist_parents;
  69 static int mergelist_cnt = 0;
  70 static int mergelist_size = 0;
  71
  72 /* Each filter_list_struct describes a singly-linked list by keeping track
  73  * of both the head and tail pointers.  The list is slightly unusual in that
  74  * a parent-dir's content can be appended to the end of the local list in a
  75  * special way:  the last item in the local list has its "next" pointer set
  76  * to point to the inherited list, but the local list's tail pointer points
  77  * at the end of the local list.  Thus, if the local list is empty, the head
  78  * will be pointing at the inherited content but the tail will be NULL.  To
  79  * help you visualize this, here are the possible list arrangements:
  80  *
  81  * Completely Empty                     Local Content Only
  82  * ==================================   ====================================
  83  * head -> NULL                         head -> Local1 -> Local2 -> NULL
  84  * tail -> NULL                         tail -------------^
  85  *
  86  * Inherited Content Only               Both Local and Inherited Content
  87  * ==================================   ====================================
  88  * head -> Parent1 -> Parent2 -> NULL   head -> L1 -> L2 -> P1 -> P2 -> NULL
  89  * tail -> NULL                         tail ---------^
  90  *
  91  * This means that anyone wanting to traverse the whole list to use it just
  92  * needs to start at the head and use the "next" pointers until it goes
  93  * NULL.  To add new local content, we insert the item after the tail item
  94  * and update the tail (obviously, if "tail" was NULL, we insert it at the
  95  * head).  To clear the local list, WE MUST NOT FREE THE INHERITED CONTENT
  96  * because it is shared between the current list and our parent list(s).
  97  * The easiest way to handle this is to simply truncate the list after the
  98  * tail item and then free the local list from the head.  When inheriting
  99  * the list for a new local dir, we just save off the filter_list_struct
 100  * values (so we can pop back to them later) and set the tail to NULL.
 101  */
 102
 103 static void teardown_mergelist(filter_rule *ex)
 104 {
 105         int j;
 106
 107         if (!ex->u.mergelist)
 108                 return;
 109
 110         if (DEBUG_GTE(FILTER, 2)) {
 111                 rprintf(FINFO, "[%s] deactivating mergelist #%d%s\n",
 112                         who_am_i(), mergelist_cnt - 1,
 113                         ex->u.mergelist->debug_type);
 114         }
 115
 116         free(ex->u.mergelist->debug_type);
 117         free(ex->u.mergelist);
 118
 119         for (j = 0; j < mergelist_cnt; j++) {
 120                 if (mergelist_parents[j] == ex) {
 121                         mergelist_parents[j] = NULL;
 122                         break;
 123                 }
 124         }
 125         while (mergelist_cnt && mergelist_parents[mergelist_cnt-1] == NULL)
 126                 mergelist_cnt--;
 127 }
 128
 129 static void free_filter(filter_rule *ex)
 130 {
 131         if (ex->rflags & FILTRULE_PERDIR_MERGE)
 132                 teardown_mergelist(ex);
 133         free(ex->pattern);
 134         free(ex);
 135 }
 136
 137 static void free_filters(filter_rule *ent)
 138 {
 139         while (ent) {
 140                 filter_rule *next = ent->next;
 141                 free_filter(ent);
 142                 ent = next;
 143         }
 144 }
 145
 146 /* Build a filter structure given a filter pattern.  The value in "pat"
 147  * is not null-terminated.  "rule" is either held or freed, so the
 148  * caller should not free it. */
 149 static void add_rule(filter_rule_list *listp, const char *pat, unsigned int pat_len,
 150                      filter_rule *rule, int xflags)
 151 {
 152         const char *cp;
 153         unsigned int pre_len, suf_len, slash_cnt = 0;
 154
 155         if (DEBUG_GTE(FILTER, 2)) {
 156                 rprintf(FINFO, "[%s] add_rule(%s%.*s%s)%s\n",
 157                         who_am_i(), get_rule_prefix(rule, pat, 0, NULL),
 158                         (int)pat_len, pat,
 159                         (rule->rflags & FILTRULE_DIRECTORY) ? "/" : "",
 160                         listp->debug_type);
 161         }
 162
 163         /* These flags also indicate that we're reading a list that
 164          * needs to be filtered now, not post-filtered later. */
 165         if (xflags & (XFLG_ANCHORED2ABS|XFLG_ABS_IF_SLASH)
 166                 && (rule->rflags & FILTRULES_SIDES)
 167                         == (am_sender ? FILTRULE_RECEIVER_SIDE : FILTRULE_SENDER_SIDE)) {
 168                 /* This filter applies only to the other side.  Drop it. */
 169                 free_filter(rule);
 170                 return;
 171         }
 172
 173         if (pat_len > 1 && pat[pat_len-1] == '/') {
 174                 pat_len--;
 175                 rule->rflags |= FILTRULE_DIRECTORY;
 176         }
 177
 178         for (cp = pat; cp < pat + pat_len; cp++) {
 179                 if (*cp == '/')
 180                         slash_cnt++;
 181         }
 182
 183         if (!(rule->rflags & (FILTRULE_ABS_PATH | FILTRULE_MERGE_FILE))
 184          && ((xflags & (XFLG_ANCHORED2ABS|XFLG_ABS_IF_SLASH) && *pat == '/')
 185           || (xflags & XFLG_ABS_IF_SLASH && slash_cnt))) {
 186                 rule->rflags |= FILTRULE_ABS_PATH;
 187                 if (*pat == '/')
 188                         pre_len = dirbuf_len - module_dirlen - 1;
 189                 else
 190                         pre_len = 0;
 191         } else
 192                 pre_len = 0;
 193
 194         /* The daemon wants dir-exclude rules to get an appended "/" + "***". */
 195         if (xflags & XFLG_DIR2WILD3
 196          && BITS_SETnUNSET(rule->rflags, FILTRULE_DIRECTORY, FILTRULE_INCLUDE)) {
 197                 rule->rflags &= ~FILTRULE_DIRECTORY;
 198                 suf_len = sizeof SLASH_WILD3_SUFFIX - 1;
 199         } else
 200                 suf_len = 0;
 201
 202         if (!(rule->pattern = new_array(char, pre_len + pat_len + suf_len + 1)))
 203                 out_of_memory("add_rule");
 204         if (pre_len) {
 205                 memcpy(rule->pattern, dirbuf + module_dirlen, pre_len);
 206                 for (cp = rule->pattern; cp < rule->pattern + pre_len; cp++) {
 207                         if (*cp == '/')
 208                                 slash_cnt++;
 209                 }
 210         }
 211         strlcpy(rule->pattern + pre_len, pat, pat_len + 1);
 212         pat_len += pre_len;
 213         if (suf_len) {
 214                 memcpy(rule->pattern + pat_len, SLASH_WILD3_SUFFIX, suf_len+1);
 215                 pat_len += suf_len;
 216                 slash_cnt++;
 217         }
 218
 219         if (strpbrk(rule->pattern, "*[?")) {
 220                 rule->rflags |= FILTRULE_WILD;
 221                 if ((cp = strstr(rule->pattern, "**")) != NULL) {
 222                         rule->rflags |= FILTRULE_WILD2;
 223                         /* If the pattern starts with **, note that. */
 224                         if (cp == rule->pattern)
 225                                 rule->rflags |= FILTRULE_WILD2_PREFIX;
 226                         /* If the pattern ends with ***, note that. */
 227                         if (pat_len >= 3
 228                          && rule->pattern[pat_len-3] == '*'
 229                          && rule->pattern[pat_len-2] == '*'
 230                          && rule->pattern[pat_len-1] == '*')
 231                                 rule->rflags |= FILTRULE_WILD3_SUFFIX;
 232                 }
 233         }
 234
 235         if (rule->rflags & FILTRULE_PERDIR_MERGE) {
 236                 filter_rule_list *lp;
 237                 unsigned int len;
 238                 int i;
 239
 240                 if ((cp = strrchr(rule->pattern, '/')) != NULL)
 241                         cp++;
 242                 else
 243                         cp = rule->pattern;
 244
 245                 /* If the local merge file was already mentioned, don't
 246                  * add it again. */
 247                 for (i = 0; i < mergelist_cnt; i++) {
 248                         filter_rule *ex = mergelist_parents[i];
 249                         const char *s;
 250                         if (!ex)
 251                                 continue;
 252                         s = strrchr(ex->pattern, '/');
 253                         if (s)
 254                                 s++;
 255                         else
 256                                 s = ex->pattern;
 257                         len = strlen(s);
 258                         if (len == pat_len - (cp - rule->pattern) && memcmp(s, cp, len) == 0) {
 259                                 free_filter(rule);
 260                                 return;
 261                         }
 262                 }
 263
 264                 if (!(lp = new_array0(filter_rule_list, 1)))
 265                         out_of_memory("add_rule");
 266                 if (asprintf(&lp->debug_type, " [per-dir %s]", cp) < 0)
 267                         out_of_memory("add_rule");
 268                 rule->u.mergelist = lp;
 269
 270                 if (mergelist_cnt == mergelist_size) {
 271                         mergelist_size += 5;
 272                         mergelist_parents = realloc_array(mergelist_parents,
 273                                                 filter_rule *,
 274                                                 mergelist_size);
 275                         if (!mergelist_parents)
 276                                 out_of_memory("add_rule");
 277                 }
 278                 if (DEBUG_GTE(FILTER, 2)) {
 279                         rprintf(FINFO, "[%s] activating mergelist #%d%s\n",
 280                                 who_am_i(), mergelist_cnt, lp->debug_type);
 281                 }
 282                 mergelist_parents[mergelist_cnt++] = rule;
 283         } else
 284                 rule->u.slash_cnt = slash_cnt;
 285
 286         if (!listp->tail) {
 287                 rule->next = listp->head;
 288                 listp->head = listp->tail = rule;
 289         } else {
 290                 rule->next = listp->tail->next;
 291                 listp->tail->next = rule;
 292                 listp->tail = rule;
 293         }
 294 }
 295
 296 /* This frees any non-inherited items, leaving just inherited items on the list. */
 297 static void pop_filter_list(filter_rule_list *listp)
 298 {
 299         filter_rule *inherited;
 300
 301         if (!listp->tail)
 302                 return;
 303
 304         inherited = listp->tail->next;
 305
 306         /* Truncate any inherited items from the local list. */
 307         listp->tail->next = NULL;
 308         /* Now free everything that is left. */
 309         free_filters(listp->head);
 310
 311         listp->head = inherited;
 312         listp->tail = NULL;
 313 }
 314
 315 /* This returns an expanded (absolute) filename for the merge-file name if
 316  * the name has any slashes in it OR if the parent_dirscan var is True;
 317  * otherwise it returns the original merge_file name.  If the len_ptr value
 318  * is non-NULL the merge_file name is limited by the referenced length
 319  * value and will be updated with the length of the resulting name.  We
 320  * always return a name that is null terminated, even if the merge_file
 321  * name was not. */
 322 static char *parse_merge_name(const char *merge_file, unsigned int *len_ptr,
 323                               unsigned int prefix_skip)
 324 {
 325         static char buf[MAXPATHLEN];
 326         char *fn, tmpbuf[MAXPATHLEN];
 327         unsigned int fn_len;
 328
 329         if (!parent_dirscan && *merge_file != '/') {
 330                 /* Return the name unchanged it doesn't have any slashes. */
 331                 if (len_ptr) {
 332                         const char *p = merge_file + *len_ptr;
 333                         while (--p > merge_file && *p != '/') {}
 334                         if (p == merge_file) {
 335                                 strlcpy(buf, merge_file, *len_ptr + 1);
 336                                 return buf;
 337                         }
 338                 } else if (strchr(merge_file, '/') == NULL)
 339                         return (char *)merge_file;
 340         }
 341
 342         fn = *merge_file == '/' ? buf : tmpbuf;
 343         if (sanitize_paths) {
 344                 const char *r = prefix_skip ? "/" : NULL;
 345                 /* null-terminate the name if it isn't already */
 346                 if (len_ptr && merge_file[*len_ptr]) {
 347                         char *to = fn == buf ? tmpbuf : buf;
 348                         strlcpy(to, merge_file, *len_ptr + 1);
 349                         merge_file = to;
 350                 }
 351                 if (!sanitize_path(fn, merge_file, r, dirbuf_depth, SP_DEFAULT)) {
 352                         rprintf(FERROR, "merge-file name overflows: %s\n",
 353                                 merge_file);
 354                         return NULL;
 355                 }
 356                 fn_len = strlen(fn);
 357         } else {
 358                 strlcpy(fn, merge_file, len_ptr ? *len_ptr + 1 : MAXPATHLEN);
 359                 fn_len = clean_fname(fn, CFN_COLLAPSE_DOT_DOT_DIRS);
 360         }
 361
 362         /* If the name isn't in buf yet, it wasn't absolute. */
 363         if (fn != buf) {
 364                 int d_len = dirbuf_len - prefix_skip;
 365                 if (d_len + fn_len >= MAXPATHLEN) {
 366                         rprintf(FERROR, "merge-file name overflows: %s\n", fn);
 367                         return NULL;
 368                 }
 369                 memcpy(buf, dirbuf + prefix_skip, d_len);
 370                 memcpy(buf + d_len, fn, fn_len + 1);
 371                 fn_len = clean_fname(buf, CFN_COLLAPSE_DOT_DOT_DIRS);
 372         }
 373
 374         if (len_ptr)
 375                 *len_ptr = fn_len;
 376         return buf;
 377 }
 378
 379 /* Sets the dirbuf and dirbuf_len values. */
 380 void set_filter_dir(const char *dir, unsigned int dirlen)
 381 {
 382         unsigned int len;
 383         if (*dir != '/') {
 384                 memcpy(dirbuf, curr_dir, curr_dir_len);
 385                 dirbuf[curr_dir_len] = '/';
 386                 len = curr_dir_len + 1;
 387                 if (len + dirlen >= MAXPATHLEN)
 388                         dirlen = 0;
 389         } else
 390                 len = 0;
 391         memcpy(dirbuf + len, dir, dirlen);
 392         dirbuf[dirlen + len] = '\0';
 393         dirbuf_len = clean_fname(dirbuf, CFN_COLLAPSE_DOT_DOT_DIRS);
 394         if (dirbuf_len > 1 && dirbuf[dirbuf_len-1] == '.'
 395             && dirbuf[dirbuf_len-2] == '/')
 396                 dirbuf_len -= 2;
 397         if (dirbuf_len != 1)
 398                 dirbuf[dirbuf_len++] = '/';
 399         dirbuf[dirbuf_len] = '\0';
 400         if (sanitize_paths)
 401                 dirbuf_depth = count_dir_elements(dirbuf + module_dirlen);
 402 }
 403
 404 /* This routine takes a per-dir merge-file entry and finishes its setup.
 405  * If the name has a path portion then we check to see if it refers to a
 406  * parent directory of the first transfer dir.  If it does, we scan all the
 407  * dirs from that point through the parent dir of the transfer dir looking
 408  * for the per-dir merge-file in each one. */
 409 static BOOL setup_merge_file(int mergelist_num, filter_rule *ex,
 410                              filter_rule_list *lp)
 411 {
 412         char buf[MAXPATHLEN];
 413         char *x, *y, *pat = ex->pattern;
 414         unsigned int len;
 415
 416         if (!(x = parse_merge_name(pat, NULL, 0)) || *x != '/')
 417                 return 0;
 418
 419         if (DEBUG_GTE(FILTER, 2)) {
 420                 rprintf(FINFO, "[%s] performing parent_dirscan for mergelist #%d%s\n",
 421                         who_am_i(), mergelist_num, lp->debug_type);
 422         }
 423         y = strrchr(x, '/');
 424         *y = '\0';
 425         ex->pattern = strdup(y+1);
 426         if (!*x)
 427                 x = "/";
 428         if (*x == '/')
 429                 strlcpy(buf, x, MAXPATHLEN);
 430         else
 431                 pathjoin(buf, MAXPATHLEN, dirbuf, x);
 432
 433         len = clean_fname(buf, CFN_COLLAPSE_DOT_DOT_DIRS);
 434         if (len != 1 && len < MAXPATHLEN-1) {
 435                 buf[len++] = '/';
 436                 buf[len] = '\0';
 437         }
 438         /* This ensures that the specified dir is a parent of the transfer. */
 439         for (x = buf, y = dirbuf; *x && *x == *y; x++, y++) {}
 440         if (*x)
 441                 y += strlen(y); /* nope -- skip the scan */
 442
 443         parent_dirscan = True;
 444         while (*y) {
 445                 char save[MAXPATHLEN];
 446                 strlcpy(save, y, MAXPATHLEN);
 447                 *y = '\0';
 448                 dirbuf_len = y - dirbuf;
 449                 strlcpy(x, ex->pattern, MAXPATHLEN - (x - buf));
 450                 parse_filter_file(lp, buf, ex, XFLG_ANCHORED2ABS);
 451                 if (ex->rflags & FILTRULE_NO_INHERIT) {
 452                         /* Free the undesired rules to clean up any per-dir
 453                          * mergelists they defined.  Otherwise pop_local_filters
 454                          * may crash trying to restore nonexistent state for
 455                          * those mergelists. */
 456                         free_filters(lp->head);
 457                         lp->head = NULL;
 458                 }
 459                 lp->tail = NULL;
 460                 strlcpy(y, save, MAXPATHLEN);
 461                 while ((*x++ = *y++) != '/') {}
 462         }
 463         parent_dirscan = False;
 464         if (DEBUG_GTE(FILTER, 2)) {
 465                 rprintf(FINFO, "[%s] completed parent_dirscan for mergelist #%d%s\n",
 466                         who_am_i(), mergelist_num, lp->debug_type);
 467         }
 468         free(pat);
 469         return 1;
 470 }
 471
 472 struct local_filter_state {
 473         int mergelist_cnt;
 474         filter_rule_list mergelists[1];
 475 };
 476
 477 /* Each time rsync changes to a new directory it call this function to
 478  * handle all the per-dir merge-files.  The "dir" value is the current path
 479  * relative to curr_dir (which might not be null-terminated).  We copy it
 480  * into dirbuf so that we can easily append a file name on the end. */
 481 void *push_local_filters(const char *dir, unsigned int dirlen)
 482 {
 483         struct local_filter_state *push;
 484         int i;
 485
 486         set_filter_dir(dir, dirlen);
 487         if (DEBUG_GTE(FILTER, 2)) {
 488                 rprintf(FINFO, "[%s] pushing local filters for %s\n",
 489                         who_am_i(), dirbuf);
 490         }
 491
 492         if (!mergelist_cnt) {
 493                 /* No old state to save and no new merge files to push. */
 494                 return NULL;
 495         }
 496
 497         push = (struct local_filter_state *)new_array(char,
 498                           sizeof (struct local_filter_state)
 499                         + (mergelist_cnt-1) * sizeof (filter_rule_list));
 500         if (!push)
 501                 out_of_memory("push_local_filters");
 502
 503         push->mergelist_cnt = mergelist_cnt;
 504         for (i = 0; i < mergelist_cnt; i++) {
 505                 filter_rule *ex = mergelist_parents[i];
 506                 if (!ex)
 507                         continue;
 508                 memcpy(&push->mergelists[i], ex->u.mergelist, sizeof (filter_rule_list));
 509         }
 510
 511         /* Note: parse_filter_file() might increase mergelist_cnt, so keep
 512          * this loop separate from the above loop. */
 513         for (i = 0; i < mergelist_cnt; i++) {
 514                 filter_rule *ex = mergelist_parents[i];
 515                 filter_rule_list *lp;
 516                 if (!ex)
 517                         continue;
 518                 lp = ex->u.mergelist;
 519
 520                 if (DEBUG_GTE(FILTER, 2)) {
 521                         rprintf(FINFO, "[%s] pushing mergelist #%d%s\n",
 522                                 who_am_i(), i, lp->debug_type);
 523                 }
 524
 525                 lp->tail = NULL; /* Switch any local rules to inherited. */
 526                 if (ex->rflags & FILTRULE_NO_INHERIT)
 527                         lp->head = NULL;
 528
 529                 if (ex->rflags & FILTRULE_FINISH_SETUP) {
 530                         ex->rflags &= ~FILTRULE_FINISH_SETUP;
 531                         if (setup_merge_file(i, ex, lp))
 532                                 set_filter_dir(dir, dirlen);
 533                 }
 534
 535                 if (strlcpy(dirbuf + dirbuf_len, ex->pattern,
 536                     MAXPATHLEN - dirbuf_len) < MAXPATHLEN - dirbuf_len) {
 537                         parse_filter_file(lp, dirbuf, ex,
 538                                           XFLG_ANCHORED2ABS);
 539                 } else {
 540                         io_error |= IOERR_GENERAL;
 541                         rprintf(FERROR,
 542                             "cannot add local filter rules in long-named directory: %s\n",
 543                             full_fname(dirbuf));
 544                 }
 545                 dirbuf[dirbuf_len] = '\0';
 546         }
 547
 548         return (void*)push;
 549 }
 550
 551 void pop_local_filters(void *mem)
 552 {
 553         struct local_filter_state *pop = (struct local_filter_state *)mem;
 554         int i;
 555         int old_mergelist_cnt = pop ? pop->mergelist_cnt : 0;
 556
 557         if (DEBUG_GTE(FILTER, 2))
 558                 rprintf(FINFO, "[%s] popping local filters\n", who_am_i());
 559
 560         for (i = mergelist_cnt; i-- > 0; ) {
 561                 filter_rule *ex = mergelist_parents[i];
 562                 filter_rule_list *lp;
 563                 if (!ex)
 564                         continue;
 565                 lp = ex->u.mergelist;
 566
 567                 if (DEBUG_GTE(FILTER, 2)) {
 568                         rprintf(FINFO, "[%s] popping mergelist #%d%s\n",
 569                                 who_am_i(), i, lp->debug_type);
 570                 }
 571
 572                 pop_filter_list(lp);
 573                 if (i >= old_mergelist_cnt && lp->head) {
 574                         /* This mergelist does not exist in the state to be restored, but it
 575                          * still has inherited rules.  This can sometimes happen if a per-dir
 576                          * merge file calls setup_merge_file() in push_local_filters() and that
 577                          * leaves some inherited rules that aren't in the pushed list state. */
 578                         if (DEBUG_GTE(FILTER, 2)) {
 579                                 rprintf(FINFO, "[%s] freeing parent_dirscan filters of mergelist #%d%s\n",
 580                                         who_am_i(), i, ex->u.mergelist->debug_type);
 581                         }
 582                         pop_filter_list(lp);
 583                 }
 584         }
 585
 586         if (!pop)
 587                 return; /* No state to restore. */
 588
 589         for (i = 0; i < old_mergelist_cnt; i++) {
 590                 filter_rule *ex = mergelist_parents[i];
 591                 if (!ex)
 592                         continue;
 593                 memcpy(ex->u.mergelist, &pop->mergelists[i], 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_flags)
 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 (!(name_flags & NAME_IS_XATTR) ^ !(ex->rflags & FILTRULE_XATTR))
 639                 return 0;
 640
 641         if (!ex->u.slash_cnt && !(ex->rflags & FILTRULE_WILD2)) {
 642                 /* If the pattern does not have any slashes AND it does
 643                  * not have a "**" (which could match a slash), then we
 644                  * just match the name portion of the path. */
 645                 if ((p = strrchr(name,'/')) != NULL)
 646                         name = p+1;
 647         } else if (ex->rflags & FILTRULE_ABS_PATH && *fname != '/'
 648             && curr_dir_len > module_dirlen + 1) {
 649                 /* If we're matching against an absolute-path pattern,
 650                  * we need to prepend our full path info. */
 651                 strings[str_cnt++] = curr_dir + module_dirlen + 1;
 652                 strings[str_cnt++] = "/";
 653         } else if (ex->rflags & FILTRULE_WILD2_PREFIX && *fname != '/') {
 654                 /* Allow "**"+"/" to match at the start of the string. */
 655                 strings[str_cnt++] = "/";
 656         }
 657         strings[str_cnt++] = name;
 658         if (name_flags & NAME_IS_DIR) {
 659                 /* Allow a trailing "/"+"***" to match the directory. */
 660                 if (ex->rflags & FILTRULE_WILD3_SUFFIX)
 661                         strings[str_cnt++] = "/";
 662         } else if (ex->rflags & FILTRULE_DIRECTORY)
 663                 return !ret_match;
 664         strings[str_cnt] = NULL;
 665
 666         if (*pattern == '/') {
 667                 anchored_match = 1;
 668                 pattern++;
 669         }
 670
 671         if (!anchored_match && ex->u.slash_cnt
 672             && !(ex->rflags & FILTRULE_WILD2)) {
 673                 /* A non-anchored match with an infix slash and no "**"
 674                  * needs to match the last slash_cnt+1 name elements. */
 675                 slash_handling = ex->u.slash_cnt + 1;
 676         } else if (!anchored_match && !(ex->rflags & FILTRULE_WILD2_PREFIX)
 677                                    && ex->rflags & FILTRULE_WILD2) {
 678                 /* A non-anchored match with an infix or trailing "**" (but not
 679                  * a prefixed "**") needs to try matching after every slash. */
 680                 slash_handling = -1;
 681         } else {
 682                 /* The pattern matches only at the start of the path or name. */
 683                 slash_handling = 0;
 684         }
 685
 686         if (ex->rflags & FILTRULE_WILD) {
 687                 if (wildmatch_array(pattern, strings, slash_handling))
 688                         return ret_match;
 689         } else if (str_cnt > 1) {
 690                 if (litmatch_array(pattern, strings, slash_handling))
 691                         return ret_match;
 692         } else if (anchored_match) {
 693                 if (strcmp(name, pattern) == 0)
 694                         return ret_match;
 695         } else {
 696                 int l1 = strlen(name);
 697                 int l2 = strlen(pattern);
 698                 if (l2 <= l1 &&
 699                     strcmp(name+(l1-l2),pattern) == 0 &&
 700                     (l1==l2 || name[l1-(l2+1)] == '/')) {
 701                         return ret_match;
 702                 }
 703         }
 704
 705         return !ret_match;
 706 }
 707
 708 static void report_filter_result(enum logcode code, char const *name,
 709                                  filter_rule const *ent,
 710                                  int name_flags, const char *type)
 711 {
 712         /* If a trailing slash is present to match only directories,
 713          * then it is stripped out by add_rule().  So as a special
 714          * case we add it back in here. */
 715
 716         if (DEBUG_GTE(FILTER, 1)) {
 717                 static char *actions[2][2]
 718                     = { {"show", "hid"}, {"risk", "protect"} };
 719                 const char *w = who_am_i();
 720                 const char *t = name_flags & NAME_IS_XATTR ? "xattr"
 721                               : name_flags & NAME_IS_DIR ? "directory"
 722                               : "file";
 723                 rprintf(code, "[%s] %sing %s %s because of pattern %s%s%s\n",
 724                     w, actions[*w!='s'][!(ent->rflags & FILTRULE_INCLUDE)],
 725                     t, name, ent->pattern,
 726                     ent->rflags & FILTRULE_DIRECTORY ? "/" : "", type);
 727         }
 728 }
 729
 730 /* This function is used to check if a file should be included/excluded
 731  * from the list of files based on its name and type etc.  The value of
 732  * filter_level is set to either SERVER_FILTERS or ALL_FILTERS. */
 733 int name_is_excluded(const char *fname, int name_flags, int filter_level)
 734 {
 735         if (daemon_filter_list.head && check_filter(&daemon_filter_list, FLOG, fname, name_flags) < 0) {
 736                 if (!(name_flags & NAME_IS_XATTR))
 737                         errno = ENOENT;
 738                 return 1;
 739         }
 740
 741         if (filter_level != ALL_FILTERS)
 742                 return 0;
 743
 744         if (filter_list.head && check_filter(&filter_list, FINFO, fname, name_flags) < 0)
 745                 return 1;
 746
 747         return 0;
 748 }
 749
 750 /* Return -1 if file "name" is defined to be excluded by the specified
 751  * exclude list, 1 if it is included, and 0 if it was not matched. */
 752 int check_filter(filter_rule_list *listp, enum logcode code,
 753                  const char *name, int name_flags)
 754 {
 755         filter_rule *ent;
 756
 757         for (ent = listp->head; ent; ent = ent->next) {
 758                 if (ignore_perishable && ent->rflags & FILTRULE_PERISHABLE)
 759                         continue;
 760                 if (ent->rflags & FILTRULE_PERDIR_MERGE) {
 761                         int rc = check_filter(ent->u.mergelist, code, name, name_flags);
 762                         if (rc)
 763                                 return rc;
 764                         continue;
 765                 }
 766                 if (ent->rflags & FILTRULE_CVS_IGNORE) {
 767                         int rc = check_filter(&cvs_filter_list, code, name, name_flags);
 768                         if (rc)
 769                                 return rc;
 770                         continue;
 771                 }
 772                 if (rule_matches(name, ent, name_flags)) {
 773                         report_filter_result(code, name, ent, name_flags, listp->debug_type);
 774                         return ent->rflags & FILTRULE_INCLUDE ? 1 : -1;
 775                 }
 776         }
 777
 778         return 0;
 779 }
 780
 781 #define RULE_STRCMP(s,r) rule_strcmp((s), (r), sizeof (r) - 1)
 782
 783 static const uchar *rule_strcmp(const uchar *str, const char *rule, int rule_len)
 784 {
 785         if (strncmp((char*)str, rule, rule_len) != 0)
 786                 return NULL;
 787         if (isspace(str[rule_len]) || str[rule_len] == '_' || !str[rule_len])
 788                 return str + rule_len - 1;
 789         if (str[rule_len] == ',')
 790                 return str + rule_len;
 791         return NULL;
 792 }
 793
 794 #define FILTRULES_FROM_CONTAINER (FILTRULE_ABS_PATH | FILTRULE_INCLUDE \
 795                                 | FILTRULE_DIRECTORY | FILTRULE_NEGATE \
 796                                 | FILTRULE_PERISHABLE)
 797
 798 /* Gets the next include/exclude rule from *rulestr_ptr and advances
 799  * *rulestr_ptr to point beyond it.  Stores the pattern's start (within
 800  * *rulestr_ptr) and length in *pat_ptr and *pat_len_ptr, and returns a newly
 801  * allocated filter_rule containing the rest of the information.  Returns
 802  * NULL if there are no more rules in the input.
 803  *
 804  * The template provides defaults for the new rule to inherit, and the
 805  * template rflags and the xflags additionally affect parsing. */
 806 static filter_rule *parse_rule_tok(const char **rulestr_ptr,
 807                                    const filter_rule *template, int xflags,
 808                                    const char **pat_ptr, unsigned int *pat_len_ptr)
 809 {
 810         const uchar *s = (const uchar *)*rulestr_ptr;
 811         filter_rule *rule;
 812         unsigned int len;
 813
 814         if (template->rflags & FILTRULE_WORD_SPLIT) {
 815                 /* Skip over any initial whitespace. */
 816                 while (isspace(*s))
 817                         s++;
 818                 /* Update to point to real start of rule. */
 819                 *rulestr_ptr = (const char *)s;
 820         }
 821         if (!*s)
 822                 return NULL;
 823
 824         if (!(rule = new0(filter_rule)))
 825                 out_of_memory("parse_rule_tok");
 826
 827         /* Inherit from the template.  Don't inherit FILTRULES_SIDES; we check
 828          * that later. */
 829         rule->rflags = template->rflags & FILTRULES_FROM_CONTAINER;
 830
 831         /* Figure out what kind of a filter rule "s" is pointing at.  Note
 832          * that if FILTRULE_NO_PREFIXES is set, the rule is either an include
 833          * or an exclude based on the inheritance of the FILTRULE_INCLUDE
 834          * flag (above).  XFLG_OLD_PREFIXES indicates a compatibility mode
 835          * for old include/exclude patterns where just "+ " and "- " are
 836          * allowed as optional prefixes.  */
 837         if (template->rflags & FILTRULE_NO_PREFIXES) {
 838                 if (*s == '!' && template->rflags & FILTRULE_CVS_IGNORE)
 839                         rule->rflags |= FILTRULE_CLEAR_LIST; /* Tentative! */
 840         } else if (xflags & XFLG_OLD_PREFIXES) {
 841                 if (*s == '-' && s[1] == ' ') {
 842                         rule->rflags &= ~FILTRULE_INCLUDE;
 843                         s += 2;
 844                 } else if (*s == '+' && s[1] == ' ') {
 845                         rule->rflags |= FILTRULE_INCLUDE;
 846                         s += 2;
 847                 } else if (*s == '!')
 848                         rule->rflags |= FILTRULE_CLEAR_LIST; /* Tentative! */
 849         } else {
 850                 char ch = 0;
 851                 BOOL prefix_specifies_side = False;
 852                 switch (*s) {
 853                 case 'c':
 854                         if ((s = RULE_STRCMP(s, "clear")) != NULL)
 855                                 ch = '!';
 856                         break;
 857                 case 'd':
 858                         if ((s = RULE_STRCMP(s, "dir-merge")) != NULL)
 859                                 ch = ':';
 860                         break;
 861                 case 'e':
 862                         if ((s = RULE_STRCMP(s, "exclude")) != NULL)
 863                                 ch = '-';
 864                         break;
 865                 case 'h':
 866                         if ((s = RULE_STRCMP(s, "hide")) != NULL)
 867                                 ch = 'H';
 868                         break;
 869                 case 'i':
 870                         if ((s = RULE_STRCMP(s, "include")) != NULL)
 871                                 ch = '+';
 872                         break;
 873                 case 'm':
 874                         if ((s = RULE_STRCMP(s, "merge")) != NULL)
 875                                 ch = '.';
 876                         break;
 877                 case 'p':
 878                         if ((s = RULE_STRCMP(s, "protect")) != NULL)
 879                                 ch = 'P';
 880                         break;
 881                 case 'r':
 882                         if ((s = RULE_STRCMP(s, "risk")) != NULL)
 883                                 ch = 'R';
 884                         break;
 885                 case 's':
 886                         if ((s = RULE_STRCMP(s, "show")) != NULL)
 887                                 ch = 'S';
 888                         break;
 889                 default:
 890                         ch = *s;
 891                         if (s[1] == ',')
 892                                 s++;
 893                         break;
 894                 }
 895                 switch (ch) {
 896                 case ':':
 897                         rule->rflags |= FILTRULE_PERDIR_MERGE
 898                                       | FILTRULE_FINISH_SETUP;
 899                         /* FALL THROUGH */
 900                 case '.':
 901                         rule->rflags |= FILTRULE_MERGE_FILE;
 902                         break;
 903                 case '+':
 904                         rule->rflags |= FILTRULE_INCLUDE;
 905                         break;
 906                 case '-':
 907                         break;
 908                 case 'S':
 909                         rule->rflags |= FILTRULE_INCLUDE;
 910                         /* FALL THROUGH */
 911                 case 'H':
 912                         rule->rflags |= FILTRULE_SENDER_SIDE;
 913                         prefix_specifies_side = True;
 914                         break;
 915                 case 'R':
 916                         rule->rflags |= FILTRULE_INCLUDE;
 917                         /* FALL THROUGH */
 918                 case 'P':
 919                         rule->rflags |= FILTRULE_RECEIVER_SIDE;
 920                         prefix_specifies_side = True;
 921                         break;
 922                 case '!':
 923                         rule->rflags |= FILTRULE_CLEAR_LIST;
 924                         break;
 925                 default:
 926                         rprintf(FERROR, "Unknown filter rule: `%s'\n", *rulestr_ptr);
 927                         exit_cleanup(RERR_SYNTAX);
 928                 }
 929                 while (ch != '!' && *++s && *s != ' ' && *s != '_') {
 930                         if (template->rflags & FILTRULE_WORD_SPLIT && isspace(*s)) {
 931                                 s--;
 932                                 break;
 933                         }
 934                         switch (*s) {
 935                         default:
 936                             invalid:
 937                                 rprintf(FERROR,
 938                                         "invalid modifier '%c' at position %d in filter rule: %s\n",
 939                                         *s, (int)(s - (const uchar *)*rulestr_ptr), *rulestr_ptr);
 940                                 exit_cleanup(RERR_SYNTAX);
 941                         case '-':
 942                                 if (!BITS_SETnUNSET(rule->rflags, FILTRULE_MERGE_FILE, FILTRULE_NO_PREFIXES))
 943                                         goto invalid;
 944                                 rule->rflags |= FILTRULE_NO_PREFIXES;
 945                                 break;
 946                         case '+':
 947                                 if (!BITS_SETnUNSET(rule->rflags, FILTRULE_MERGE_FILE, FILTRULE_NO_PREFIXES))
 948                                         goto invalid;
 949                                 rule->rflags |= FILTRULE_NO_PREFIXES
 950                                               | FILTRULE_INCLUDE;
 951                                 break;
 952                         case '/':
 953                                 rule->rflags |= FILTRULE_ABS_PATH;
 954                                 break;
 955                         case '!':
 956                                 /* Negation really goes with the pattern, so it
 957                                  * isn't useful as a merge-file default. */
 958                                 if (rule->rflags & FILTRULE_MERGE_FILE)
 959                                         goto invalid;
 960                                 rule->rflags |= FILTRULE_NEGATE;
 961                                 break;
 962                         case 'C':
 963                                 if (rule->rflags & FILTRULE_NO_PREFIXES || prefix_specifies_side)
 964                                         goto invalid;
 965                                 rule->rflags |= FILTRULE_NO_PREFIXES
 966                                               | FILTRULE_WORD_SPLIT
 967                                               | FILTRULE_NO_INHERIT
 968                                               | FILTRULE_CVS_IGNORE;
 969                                 break;
 970                         case 'e':
 971                                 if (!(rule->rflags & FILTRULE_MERGE_FILE))
 972                                         goto invalid;
 973                                 rule->rflags |= FILTRULE_EXCLUDE_SELF;
 974                                 break;
 975                         case 'n':
 976                                 if (!(rule->rflags & FILTRULE_MERGE_FILE))
 977                                         goto invalid;
 978                                 rule->rflags |= FILTRULE_NO_INHERIT;
 979                                 break;
 980                         case 'p':
 981                                 rule->rflags |= FILTRULE_PERISHABLE;
 982                                 break;
 983                         case 'r':
 984                                 if (prefix_specifies_side)
 985                                         goto invalid;
 986                                 rule->rflags |= FILTRULE_RECEIVER_SIDE;
 987                                 break;
 988                         case 's':
 989                                 if (prefix_specifies_side)
 990                                         goto invalid;
 991                                 rule->rflags |= FILTRULE_SENDER_SIDE;
 992                                 break;
 993                         case 'w':
 994                                 if (!(rule->rflags & FILTRULE_MERGE_FILE))
 995                                         goto invalid;
 996                                 rule->rflags |= FILTRULE_WORD_SPLIT;
 997                                 break;
 998                         case 'x':
 999                                 rule->rflags |= FILTRULE_XATTR;
1000                                 saw_xattr_filter = 1;
1001                                 break;
1002                         }
1003                 }
1004                 if (*s)
1005                         s++;
1006         }
1007         if (template->rflags & FILTRULES_SIDES) {
1008                 if (rule->rflags & FILTRULES_SIDES) {
1009                         /* The filter and template both specify side(s).  This
1010                          * is dodgy (and won't work correctly if the template is
1011                          * a one-sided per-dir merge rule), so reject it. */
1012                         rprintf(FERROR,
1013                                 "specified-side merge file contains specified-side filter: %s\n",
1014                                 *rulestr_ptr);
1015                         exit_cleanup(RERR_SYNTAX);
1016                 }
1017                 rule->rflags |= template->rflags & FILTRULES_SIDES;
1018         }
1019
1020         if (template->rflags & FILTRULE_WORD_SPLIT) {
1021                 const uchar *cp = s;
1022                 /* Token ends at whitespace or the end of the string. */
1023                 while (!isspace(*cp) && *cp != '\0')
1024                         cp++;
1025                 len = cp - s;
1026         } else
1027                 len = strlen((char*)s);
1028
1029         if (rule->rflags & FILTRULE_CLEAR_LIST) {
1030                 if (!(rule->rflags & FILTRULE_NO_PREFIXES)
1031                  && !(xflags & XFLG_OLD_PREFIXES) && len) {
1032                         rprintf(FERROR,
1033                                 "'!' rule has trailing characters: %s\n", *rulestr_ptr);
1034                         exit_cleanup(RERR_SYNTAX);
1035                 }
1036                 if (len > 1)
1037                         rule->rflags &= ~FILTRULE_CLEAR_LIST;
1038         } else if (!len && !(rule->rflags & FILTRULE_CVS_IGNORE)) {
1039                 rprintf(FERROR, "unexpected end of filter rule: %s\n", *rulestr_ptr);
1040                 exit_cleanup(RERR_SYNTAX);
1041         }
1042
1043         /* --delete-excluded turns an un-modified include/exclude into a sender-side rule.  */
1044         if (delete_excluded
1045          && !(rule->rflags & (FILTRULES_SIDES|FILTRULE_MERGE_FILE|FILTRULE_PERDIR_MERGE)))
1046                 rule->rflags |= FILTRULE_SENDER_SIDE;
1047
1048         *pat_ptr = (const char *)s;
1049         *pat_len_ptr = len;
1050         *rulestr_ptr = *pat_ptr + len;
1051         return rule;
1052 }
1053
1054 static char default_cvsignore[] =
1055         /* These default ignored items come from the CVS manual. */
1056         "RCS SCCS CVS CVS.adm RCSLOG cvslog.* tags TAGS"
1057         " .make.state .nse_depinfo *~ #* .#* ,* _$* *$"
1058         " *.old *.bak *.BAK *.orig *.rej .del-*"
1059         " *.a *.olb *.o *.obj *.so *.exe"
1060         " *.Z *.elc *.ln core"
1061         /* The rest we added to suit ourself. */
1062         " .svn/ .git/ .hg/ .bzr/";
1063
1064 static void get_cvs_excludes(uint32 rflags)
1065 {
1066         static int initialized = 0;
1067         char *p, fname[MAXPATHLEN];
1068
1069         if (initialized)
1070                 return;
1071         initialized = 1;
1072
1073         parse_filter_str(&cvs_filter_list, default_cvsignore,
1074                          rule_template(rflags | (protocol_version >= 30 ? FILTRULE_PERISHABLE : 0)),
1075                          0);
1076
1077         p = module_id >= 0 && lp_use_chroot(module_id) ? "/" : getenv("HOME");
1078         if (p && pathjoin(fname, MAXPATHLEN, p, ".cvsignore") < MAXPATHLEN)
1079                 parse_filter_file(&cvs_filter_list, fname, rule_template(rflags), 0);
1080
1081         parse_filter_str(&cvs_filter_list, getenv("CVSIGNORE"), rule_template(rflags), 0);
1082 }
1083
1084 const filter_rule *rule_template(uint32 rflags)
1085 {
1086         static filter_rule template; /* zero-initialized */
1087         template.rflags = rflags;
1088         return &template;
1089 }
1090
1091 void parse_filter_str(filter_rule_list *listp, const char *rulestr,
1092                      const filter_rule *template, int xflags)
1093 {
1094         filter_rule *rule;
1095         const char *pat;
1096         unsigned int pat_len;
1097
1098         if (!rulestr)
1099                 return;
1100
1101         while (1) {
1102                 uint32 new_rflags;
1103
1104                 /* Remember that the returned string is NOT '\0' terminated! */
1105                 if (!(rule = parse_rule_tok(&rulestr, template, xflags, &pat, &pat_len)))
1106                         break;
1107
1108                 if (pat_len >= MAXPATHLEN) {
1109                         rprintf(FERROR, "discarding over-long filter: %.*s\n",
1110                                 (int)pat_len, pat);
1111                     free_continue:
1112                         free_filter(rule);
1113                         continue;
1114                 }
1115
1116                 new_rflags = rule->rflags;
1117                 if (new_rflags & FILTRULE_CLEAR_LIST) {
1118                         if (DEBUG_GTE(FILTER, 2)) {
1119                                 rprintf(FINFO,
1120                                         "[%s] clearing filter list%s\n",
1121                                         who_am_i(), listp->debug_type);
1122                         }
1123                         pop_filter_list(listp);
1124                         listp->head = NULL;
1125                         goto free_continue;
1126                 }
1127
1128                 if (new_rflags & FILTRULE_MERGE_FILE) {
1129                         if (!pat_len) {
1130                                 pat = ".cvsignore";
1131                                 pat_len = 10;
1132                         }
1133                         if (new_rflags & FILTRULE_EXCLUDE_SELF) {
1134                                 const char *name;
1135                                 filter_rule *excl_self;
1136
1137                                 if (!(excl_self = new0(filter_rule)))
1138                                         out_of_memory("parse_filter_str");
1139                                 /* Find the beginning of the basename and add an exclude for it. */
1140                                 for (name = pat + pat_len; name > pat && name[-1] != '/'; name--) {}
1141                                 add_rule(listp, name, (pat + pat_len) - name, excl_self, 0);
1142                                 rule->rflags &= ~FILTRULE_EXCLUDE_SELF;
1143                         }
1144                         if (new_rflags & FILTRULE_PERDIR_MERGE) {
1145                                 if (parent_dirscan) {
1146                                         const char *p;
1147                                         unsigned int len = pat_len;
1148                                         if ((p = parse_merge_name(pat, &len, module_dirlen)))
1149                                                 add_rule(listp, p, len, rule, 0);
1150                                         else
1151                                                 free_filter(rule);
1152                                         continue;
1153                                 }
1154                         } else {
1155                                 const char *p;
1156                                 unsigned int len = pat_len;
1157                                 if ((p = parse_merge_name(pat, &len, 0)))
1158                                         parse_filter_file(listp, p, rule, XFLG_FATAL_ERRORS);
1159                                 free_filter(rule);
1160                                 continue;
1161                         }
1162                 }
1163
1164                 add_rule(listp, pat, pat_len, rule, xflags);
1165
1166                 if (new_rflags & FILTRULE_CVS_IGNORE
1167                     && !(new_rflags & FILTRULE_MERGE_FILE))
1168                         get_cvs_excludes(new_rflags);
1169         }
1170 }
1171
1172 void parse_filter_file(filter_rule_list *listp, const char *fname, const filter_rule *template, int xflags)
1173 {
1174         FILE *fp;
1175         char line[BIGPATHBUFLEN];
1176         char *eob = line + sizeof line - 1;
1177         BOOL word_split = (template->rflags & FILTRULE_WORD_SPLIT) != 0;
1178
1179         if (!fname || !*fname)
1180                 return;
1181
1182         if (*fname != '-' || fname[1] || am_server) {
1183                 if (daemon_filter_list.head) {
1184                         strlcpy(line, fname, sizeof line);
1185                         clean_fname(line, CFN_COLLAPSE_DOT_DOT_DIRS);
1186                         if (check_filter(&daemon_filter_list, FLOG, line, 0) < 0)
1187                                 fp = NULL;
1188                         else
1189                                 fp = fopen(line, "rb");
1190                 } else
1191                         fp = fopen(fname, "rb");
1192         } else
1193                 fp = stdin;
1194
1195         if (DEBUG_GTE(FILTER, 2)) {
1196                 rprintf(FINFO, "[%s] parse_filter_file(%s,%x,%x)%s\n",
1197                         who_am_i(), fname, template->rflags, xflags,
1198                         fp ? "" : " [not found]");
1199         }
1200
1201         if (!fp) {
1202                 if (xflags & XFLG_FATAL_ERRORS) {
1203                         rsyserr(FERROR, errno,
1204                                 "failed to open %sclude file %s",
1205                                 template->rflags & FILTRULE_INCLUDE ? "in" : "ex",
1206                                 fname);
1207                         exit_cleanup(RERR_FILEIO);
1208                 }
1209                 return;
1210         }
1211         dirbuf[dirbuf_len] = '\0';
1212
1213         while (1) {
1214                 char *s = line;
1215                 int ch, overflow = 0;
1216                 while (1) {
1217                         if ((ch = getc(fp)) == EOF) {
1218                                 if (ferror(fp) && errno == EINTR) {
1219                                         clearerr(fp);
1220                                         continue;
1221                                 }
1222                                 break;
1223                         }
1224                         if (word_split && isspace(ch))
1225                                 break;
1226                         if (eol_nulls? !ch : (ch == '\n' || ch == '\r'))
1227                                 break;
1228                         if (s < eob)
1229                                 *s++ = ch;
1230                         else
1231                                 overflow = 1;
1232                 }
1233                 if (overflow) {
1234                         rprintf(FERROR, "discarding over-long filter: %s...\n", line);
1235                         s = line;
1236                 }
1237                 *s = '\0';
1238                 /* Skip an empty token and (when line parsing) comments. */
1239                 if (*line && (word_split || (*line != ';' && *line != '#')))
1240                         parse_filter_str(listp, line, template, xflags);
1241                 if (ch == EOF)
1242                         break;
1243         }
1244         fclose(fp);
1245 }
1246
1247 /* If the "for_xfer" flag is set, the prefix is made compatible with the
1248  * current protocol_version (if possible) or a NULL is returned (if not
1249  * possible). */
1250 char *get_rule_prefix(filter_rule *rule, const char *pat, int for_xfer,
1251                       unsigned int *plen_ptr)
1252 {
1253         static char buf[MAX_RULE_PREFIX+1];
1254         char *op = buf;
1255         int legal_len = for_xfer && protocol_version < 29 ? 1 : MAX_RULE_PREFIX-1;
1256
1257         if (rule->rflags & FILTRULE_PERDIR_MERGE) {
1258                 if (legal_len == 1)
1259                         return NULL;
1260                 *op++ = ':';
1261         } else if (rule->rflags & FILTRULE_INCLUDE)
1262                 *op++ = '+';
1263         else if (legal_len != 1
1264             || ((*pat == '-' || *pat == '+') && pat[1] == ' '))
1265                 *op++ = '-';
1266         else
1267                 legal_len = 0;
1268
1269         if (rule->rflags & FILTRULE_ABS_PATH)
1270                 *op++ = '/';
1271         if (rule->rflags & FILTRULE_NEGATE)
1272                 *op++ = '!';
1273         if (rule->rflags & FILTRULE_CVS_IGNORE)
1274                 *op++ = 'C';
1275         else {
1276                 if (rule->rflags & FILTRULE_NO_INHERIT)
1277                         *op++ = 'n';
1278                 if (rule->rflags & FILTRULE_WORD_SPLIT)
1279                         *op++ = 'w';
1280                 if (rule->rflags & FILTRULE_NO_PREFIXES) {
1281                         if (rule->rflags & FILTRULE_INCLUDE)
1282                                 *op++ = '+';
1283                         else
1284                                 *op++ = '-';
1285                 }
1286         }
1287         if (rule->rflags & FILTRULE_EXCLUDE_SELF)
1288                 *op++ = 'e';
1289         if (rule->rflags & FILTRULE_SENDER_SIDE
1290             && (!for_xfer || protocol_version >= 29))
1291                 *op++ = 's';
1292         if (rule->rflags & FILTRULE_RECEIVER_SIDE
1293             && (!for_xfer || protocol_version >= 29
1294              || (delete_excluded && am_sender)))
1295                 *op++ = 'r';
1296         if (rule->rflags & FILTRULE_PERISHABLE) {
1297                 if (!for_xfer || protocol_version >= 30)
1298                         *op++ = 'p';
1299                 else if (am_sender)
1300                         return NULL;
1301         }
1302         if (op - buf > legal_len)
1303                 return NULL;
1304         if (legal_len)
1305                 *op++ = ' ';
1306         *op = '\0';
1307         if (plen_ptr)
1308                 *plen_ptr = op - buf;
1309         return buf;
1310 }
1311
1312 static void send_rules(int f_out, filter_rule_list *flp)
1313 {
1314         filter_rule *ent, *prev = NULL;
1315
1316         for (ent = flp->head; ent; ent = ent->next) {
1317                 unsigned int len, plen, dlen;
1318                 int elide = 0;
1319                 char *p;
1320
1321                 /* Note we need to check delete_excluded here in addition to
1322                  * the code in parse_rule_tok() because some rules may have
1323                  * been added before we found the --delete-excluded option.
1324                  * We must also elide any CVS merge-file rules to avoid a
1325                  * backward compatibility problem, and we elide any no-prefix
1326                  * merge files as an optimization (since they can only have
1327                  * include/exclude rules). */
1328                 if (ent->rflags & FILTRULE_SENDER_SIDE)
1329                         elide = am_sender ? 1 : -1;
1330                 if (ent->rflags & FILTRULE_RECEIVER_SIDE)
1331                         elide = elide ? 0 : am_sender ? -1 : 1;
1332                 else if (delete_excluded && !elide
1333                  && (!(ent->rflags & FILTRULE_PERDIR_MERGE)
1334                   || ent->rflags & FILTRULE_NO_PREFIXES))
1335                         elide = am_sender ? 1 : -1;
1336                 if (elide < 0) {
1337                         if (prev)
1338                                 prev->next = ent->next;
1339                         else
1340                                 flp->head = ent->next;
1341                 } else
1342                         prev = ent;
1343                 if (elide > 0)
1344                         continue;
1345                 if (ent->rflags & FILTRULE_CVS_IGNORE
1346                     && !(ent->rflags & FILTRULE_MERGE_FILE)) {
1347                         int f = am_sender || protocol_version < 29 ? f_out : -2;
1348                         send_rules(f, &cvs_filter_list);
1349                         if (f == f_out)
1350                                 continue;
1351                 }
1352                 p = get_rule_prefix(ent, ent->pattern, 1, &plen);
1353                 if (!p) {
1354                         rprintf(FERROR,
1355                                 "filter rules are too modern for remote rsync.\n");
1356                         exit_cleanup(RERR_PROTOCOL);
1357                 }
1358                 if (f_out < 0)
1359                         continue;
1360                 len = strlen(ent->pattern);
1361                 dlen = ent->rflags & FILTRULE_DIRECTORY ? 1 : 0;
1362                 if (!(plen + len + dlen))
1363                         continue;
1364                 write_int(f_out, plen + len + dlen);
1365                 if (plen)
1366                         write_buf(f_out, p, plen);
1367                 write_buf(f_out, ent->pattern, len);
1368                 if (dlen)
1369                         write_byte(f_out, '/');
1370         }
1371         flp->tail = prev;
1372 }
1373
1374 /* This is only called by the client. */
1375 void send_filter_list(int f_out)
1376 {
1377         int receiver_wants_list = prune_empty_dirs
1378             || (delete_mode && (!delete_excluded || protocol_version >= 29));
1379
1380         if (local_server || (am_sender && !receiver_wants_list))
1381                 f_out = -1;
1382         if (cvs_exclude && am_sender) {
1383                 if (protocol_version >= 29)
1384                         parse_filter_str(&filter_list, ":C", rule_template(0), 0);
1385                 parse_filter_str(&filter_list, "-C", rule_template(0), 0);
1386         }
1387
1388         send_rules(f_out, &filter_list);
1389
1390         if (f_out >= 0)
1391                 write_int(f_out, 0);
1392
1393         if (cvs_exclude) {
1394                 if (!am_sender || protocol_version < 29)
1395                         parse_filter_str(&filter_list, ":C", rule_template(0), 0);
1396                 if (!am_sender)
1397                         parse_filter_str(&filter_list, "-C", rule_template(0), 0);
1398         }
1399 }
1400
1401 /* This is only called by the server. */
1402 void recv_filter_list(int f_in)
1403 {
1404         char line[BIGPATHBUFLEN];
1405         int xflags = protocol_version >= 29 ? 0 : XFLG_OLD_PREFIXES;
1406         int receiver_wants_list = prune_empty_dirs
1407             || (delete_mode
1408              && (!delete_excluded || protocol_version >= 29));
1409         unsigned int len;
1410
1411         if (!local_server && (am_sender || receiver_wants_list)) {
1412                 while ((len = read_int(f_in)) != 0) {
1413                         if (len >= sizeof line)
1414                                 overflow_exit("recv_rules");
1415                         read_sbuf(f_in, line, len);
1416                         parse_filter_str(&filter_list, line, rule_template(0), xflags);
1417                 }
1418         }
1419
1420         if (cvs_exclude) {
1421                 if (local_server || am_sender || protocol_version < 29)
1422                         parse_filter_str(&filter_list, ":C", rule_template(0), 0);
1423                 if (local_server || am_sender)
1424                         parse_filter_str(&filter_list, "-C", rule_template(0), 0);
1425         }
1426
1427         if (local_server) /* filter out any rules that aren't for us. */
1428                 send_rules(-1, &filter_list);
1429 }